WO2005045204A9

WO2005045204A9 - Method and arrangement for recovering energy and chemicals

Info

Publication number: WO2005045204A9
Application number: PCT/SE2004/001465
Authority: WO
Inventors: Bengt Henry Nilsson
Original assignee: Ultirec; Bengt Henry Nilsson
Priority date: 2003-10-15
Filing date: 2004-10-13
Publication date: 2005-11-03
Also published as: WO2005045204A1; SE0302718L; SE526905C2; SE0302718D0

Abstract

The present invention relates to a process for recovering energy and chemicals from a fuel comprising a part or parts of: hydrogen, hydrocarbon and hydrogen compounds by combustion/thermal decomposition during partial and/or total oxidation, in at least one reaction chamber during at least one reaction progress above atmospheric pressure after which produced gas, superheated or during partial or total moisture saturation, with the content of chemical and/or physical energy to be cleaned during the condensation of vaporized agents and compounds during the expansion cooling by at least one expansion turbine step of at least one partial step when from the fuel oxidation progress originating gas carried sub-/microscopic and visual dust particles are wetted by condensation, which condensation preferably comprises steam when appropriate also by other condensable agents and compounds as volatilizable metals/heavy metals as well as volatilizable hydrocarbons, when said dust particles constitute condensation nuclei during the condensation, whereby the weight of said dust particles is increased whereupon said dust particles are transferred from the gas phase to the liquid phase, which phases are separated by at least one separation device, simultaneously when the gas phase contains chemical energy, said energy is utilized for production of chemicals and/or energy, while the physical energy during the expansion cooling is converted into power by an expander turbine connected generator, or used for driving a stationary machine/engine or a mobile machine/engine, while further chemicals are recovered as a phase of solid and/or molten material and/or said sub-/microscopic and visual dust particles and/or in aqueous form and/or in gaseous state.

Description

METHOD AJND ARRANGEMENT FOR RECOVERING ENERGY AND CHEMICALS

STATE OF THE ART AND PROBLEMS

At all kinds of combustion regarding energy production there arc a number of efficiency restraining areas on. the heat exchangers which will lower the efficiency of the energy product] on- The convertible part of the energy is indicated as exergy and the non convertible part is indicated as anergy. The following relationship thus prevails: Energy = Exergy + Anergy. Therefore the aim must be to do not "destroy" high quality exergy by converting it to inapplicable energy — that is ajiergy. Many of the established energy recovery processes have great exergy losses. An indication of this is large cooling water consumption with the corresponding amount of waste heat Combined power and heating plants are more and more used for energy production from hydrocarbon compounds in the form of as well renewable fuels as fuels of fossil background- The combined power and heating plants generate both electric current/power and a great part of high-temperature hot water — the latter unfortunately at least 2/3 of the total energy amount. The requirement is therefore a well built out district heating system which by that constitutes the utmost production limit for the combined power and hearing plant. The global energy situation is precarious in view of increasingly high set environmental requϊrexαents- Fuels of fossil background must he avoided and in the long run completely eliminated, as these are a limited resource, and to reduce/eliminate the emission of fossil carbon dioxide. Also emissions to a much larger extent of green-house supported gases of nitrogen dioxide and volatile organic agents and compounds, as well for allergy, asthma, cancer as for lung diseases and for heart and blood-vessels unhealthy inhalatjonal dust particles must immediately be reduced radically and eliminated in the long run. Furthermore, in many countries forces are ai work to carry through a nuclear phase-out By that there only remains a future cycling/revolution adapted society based on renewable energy sources — i.e. revolution fuels. Here the bio energy has a very advanced place. However, increased bio energy utilization takes place in powerful competition with other interested parties as the established pulp and saw mill industry. The pulping industries of the world together handle a gigantic amount of renewable energy in the form of biomass as raw material for pulp production. Depending on production method and tvpe of paper products, the real part of used biomass for paper production is only about 45-55 %. The remaining part of the biomass — thus about half the amount— constitutes a high-quality liquid bio fuel mixed with the chemical contents of the waste liquors. Besides, these liquors contain in most cases alkali compounds which have a catalysing and positive effect on the combustion, progress. The recovery potential of bio energy in. the pulp mills coincides well with the global need of increased utilization of revolution based energy. The great possibility is grounded on the fact that the handling of the raw material/bio energy is already established as well as the re-growth of the biomass itself is secured. Further investments regarding pulp production in order to make possible an increased utilization of unchanged amount of bio energy are thus not necessary. On the other hand, there is a need for a completely new procedure for energy recovering from the available bio fuel with the intention of reducing the exergy losses and above all of giving priority to the efficiency of (electric) power generation. The need also comprises the emission situation to the air and water — i. e. the environmental aspect. The ultimate pulp mill must be seen from an overall perspective as a natural part in a well balanced ecological process with integrated partial processes, where the energy excess of the pulp mill essentially is used for power generation. Power producers all over the world are mobilizing enormous resources to find technical solutions for handling generated fossil carbon dioxide and by thai, during a transitional period, make continuous combustion of these fossil fuels possible. Fossil fuels will most probably dominate the world during additionally two, three generations. This handling of carbon dioxide means that the gas is separated from flue gas and compressed to condensation (liquefied) to be utilized within different markets. An alternative which has grown stronger during the last years means storage/final waste disposal of liquefied carbon dioxide in a suitable ground, for example porous sandstone, very deep or in emptied oil wells, natural gas fields etc. It has not yet been worked out any well functioning method for the recovery/separation of carbon dioxide with consideration to environment and economy — the latter principally regarding availability, energy efficiency and in small scale. Regarding the present energy balance of resources in many countries there often exist imbalance and depends on the supply of a couple of the energy types: fossil fuels, nuclear power, water- power and bio fuels. Thus, too often "a third leg" is missing in order to give necessary stability to the energy balance. This stabilizing "third leg" could be composed of bio fuel supply by the pulping industry where this is possible and for the time being of the handling/taking care of the carbon dioxide of the fossil fuels. The environmental aspect is also about the need of some form of mini power stations and the constantly growing transport

scarce form-of qixεter cf-a town, with possibility to adjust the distribution between produced (electric) power and heal according to the needs and/or the time of the year. The possibilities of the transport sector to a radical change of the emission situation, are perhaps the utmost greatest environmental problem. The technological development for as well combined power and heating plants as the transport sector has ceased. The respective technological area has during a long time been refined and optimized, but now a great technological leap is needed.

The recovery technology of the pulping industry has by tradition been most concentrated on getting back the cooking chemicals and secondly to produce steam for the pulping process with a certain excess as high pressure steam for (electric) power — henceforward in the present invention only named power - generation by generators connected to steam turbines. The digester waste liquor content of dissolved organic substance is also used as a fuel for conversion/thermal decomposition of recovered digester chemicals in a so called Tomlinson- boiler - most often called recovery boiler. At present, this constitutes the heart in the recovery system of the pulping industry and is the most expensive unit in the pulping production line. The recovery boiler was introduced already during the nineteen-thirties and is very sensitive for disturbances from operation-, maintenance — and safety point of view. The boiler is completely static from chemical recovery point of view and does not in any way fulfil the present process requirements of the delignification process - among others the requirements of cooking with optimized sulphidity profile and the recovery of sulphide free alkali — mainly for bleaching. The recovery system will therefore be the key to the control of the chemical balance of the pulp milk with direction on separating the sodium-/potassium compounds from the sulphur compounds and to eject/separate none process elements (NPE), comprising all forms of metals and chlorides out of the chemical cycle. From capacity point of view there is a process requirement on high content of dry solids (DS) of the waste liquor going to the recovery boiler. The flue gas -from the boiler brings a great quantity of alkaline dust particles as sub-/microscopϊc and visual particles, so called fly ash, which in spite of installation of expensive systems in the form of electrical filters and gas scrubbers more or less continuously blow out a partial flow of this dust Traditionally, the pulping processes embody very large exergy losses and are therefore consumers of huge amounts of cooling water with the corresponding generation of more or less low-grade warm water. Considerable steam users are the evaporation apparatus/effects before the recovery boiler. Here for example the released black liquor of DS-percentage 15-17 % from the sulphate pulp digester is evaporated and via the mixed-base liquor/intermediate liquor concentration further evaporated to heavy black Iiquor of around 75%-DS. Nowadays, also super concentrators are used to further increase the DS-percentage up to the level of 85-87 % with the corresponding increased consumption of intermediate pressure steam. The effects/heat exchangers of the evaporation have the tendency at higher DS-percentage to obtain coverings, incrusts/fouling that are difficult to dissolve, on the liquor side of the heat exchangers and must be shut down and washed regularly. At DS-percentages above the area 45-55 %, the solubility of the black liquor content of among others sodium carbonate (Na₂CO₃) and sodium sulphate (Na^SOa) is reduced which tends to precipitate. Further the heavy black liquor with an increased DS- percentage obtains an exponential increase of the viscosity - already pronounced over DS- percentage around 65 % - and is by that difficult to handle. An extra black liquor pre treatment stage during increased temperature needs to be installed in order to decrease the viscosity. The installation is expensive and further increases the consumption of valuable intermediate/high pressure steam. The evaporation is a gradual process, from overpressure down to negative pressure/vacuum, where mixed-base liquor/intermediate liquor is stored in big tanks for separation of the light floating sulphate soap. The separation constitutes a condition of the continued evaporation up to DS-percenlages above the intermediate liquor DS-area in order to prevent formation of foam and minimize the coating as fouling/incrusts on the liquor side of the heat surfaces. Separated soap has a certain market value and is offered for sale for external further treatment and/or is used within the mill as a fuel. In most cases, the soap handling is not economically defensible but principally constitutes a process demand for the continued DS-increase of the black liquor. The possibility of a modern (read autumn 2003) recovery boiler for recovering energy during combustion of black liquor is distributed as follows:

• Power 12 %

• Steam production 54 %

• Energy losses 34 %

As can be seen from above, the recovery boiler process comprises a great part of exergy losses.

The latest attempts of development within the recovery area have been black liquor gasification. Studies were made already at the end of the niαeteen-fifties. There are two different kinds of gasification processes, low temperature gasification and high temperature/ melt gasification. When using the low temperature gasification, below melting point 760 - 800⁰C, this results iα the recovery of chemicals in the form of sodium carbonate (Na₂CO₃) as a solid phase and a fuel gas containing sulphur as hydrogen sulphide (H₂S). Low temperature g^~a^tjScSchiκ^rx^^≤rieTrLae^"pτIcϊplarltrpTτ-Sε Εkptcted^'rSIEcurScs crsnsϊstt5rsτ:crSaΞi psxi of formed sodium sulphide (Na₂S) as a melt phase and insufficient carbon conversion which together require a complicated after-treatmeniL The other gasification process, the melting process, with a theoretical melting temperature above SOO⁰C but according to experiences with a necessary reaction temperature during the gasification "within the temperature interval 960 - 1100°C. The melt fraction contains botb of sodium carbonate (Na^COs), some sodium hydroxide (NaOH) and sodium sulphide (Na₂S) with the remaining amount of sulphur as hydrogen sulphide (H₂S) into the fuel gas.

The engineering company- KLamyr AB, Karlstad, Sweden began in 1989 to introduce the so -called "Chemrec-booster"- concept, which is a melting-process. This concept resulted in two ^' installations with the intention of only increasing the capacity of the chemical recovery. The concept is static regarding recovery of chemicals and has even inferior energy recovery than the recovery boiler. Both the installations gave the experiences, regarding the required temperature level of the gasification process, that temperatures above 900⁰C there is gaseous alkali in. considerable quantities in the form of monatomic sodium/potassium (Na/K) and sodium hydroxide/potassium hydroxide (NaOH/KOH) with presence in about equal parts. These are increasing in quantity exponentially with the temperature increase above 900^DC. The reaction place foτ this gaseous alkali is in the main during the beginning of the reaction progress. Very serious chemical attacks on the ulterior ceramic lining of the reactor - essentially the upper 1/3 part — indicate this. Further an experience of increased temperature level during the reaction progress is the increased viscosity of the gas compounds. By this the in mixing of oxidants is more difficult, with the following restrictions in the diffusion controlled reaction progress, owing to the occurrence of reaction retarding laminar boundary layers. Gases of high viscosity also mean formation of efficiency retarding strake formation/stagnant zones in the reaction vessel, which to a great extent shorter* the very sensible, real retention time for the reaction progress.

A pressurized concept was launched by Karxiyr AB during the early nineteen-nineties and was based on so called "combi-'Vcombϊned cycle — integrated gasification combined cycle (IGCC). This comb! concept comprises as well gas turbine as steam turbine, both with adherent electric generators. The expectations were by this to double the power generation in comparison with the established recovery boiler process. The combi concept can be seen in the patent documents SE-C-448 173 and US 4.808.264. The combi concept claims to a still more extent than the recovery boiler black liquor of the highest possible DS -content in order to obtain fuel gas of a sufficiently high heat value, thus a great amount of chemical energy for

compressed air as oxidizing agent for the reaction progress this implies that a. great amount of inert nitrogen must be compressed and heated up to the reaction temperature. The fuel gas is by this a typical low-quality gas -which is not adjusted to standard gas turbines. This will limit the turbine selection and by thai the costs and the complication degree will be increased to a great extent for the combi concept The concept therefore requires oxygen as oxidizing agent which means investments in expensive and energy demanding separation plant. In conformity with most of the systems for energy production also tbe combi concept has inconvenient exergy losses with corresponding cooling water need and production of waste water. The split of sσdium- and sulphur compounds between the melt and gas- phase, which is so important for the delignification partial processes, is limited. At all combustion of waste liquors from tbe pulping industry during partial oxidation, thus understoichiometric combustion, the distribution of the fuel gas content between chemical and physical energy is quite decisive for the continued energy recovery. At an operation example with black liquor of DS-content 73 %, oxygen 95 %, reaction temperature 950⁰C, reaction pressure 32 bar (a) the part of physical energy, latent and sensible heat, of the fuel gas is about 37 %. By that tbe part of chemical energy will be sufficient for combustion in the combustion chamber of the gas turbine - effective heat value 8.303 kJ/Nτn³ dry gas. At a similar operation example but wifh black liquor of lower DS-content 43 %₅ thus a more water content, the part of physical energy in the fuel gas increases to around 73 %. By that the part of chemical energy in the fuel gas will be too low for the combustion chamber of the gas turbine — effective heat value 3.733 kJ/Nm³ dry gas. During black liquor gasification the operation criteria of the reaction progress are thus quite decisive for the recovery of as well chemicals as energy. Black Liquor of high DS- content and the subsequent high viscosity results in restrictions in the burner system of the reaction vessel/gasifier. These restrictions comprise the drop formation ability, mainly the possibility of small droplets formation and the very sensible drop size distribution. Further restrictions are the tendency of plug formation in the narrow, very sensible, channels of the burner spray nozzle.' Black liquor of high DS-content/viscosity, often with content of detached incrusts- creates troublesome erosion in the carefully dimensioned channels of the burner spray nozzle. The restrictions in the burner system impair direct the so called carbon conversion degree. This constitutes one of the most essential control parameters of the reaction progress and is a measure of the amount of remaining, un-burnt carbon — thus the amount of soot and hydrocarbon compounds. The carbon conversion degree must exceed 99,5 %. Restrictions in the burner system must not be compensated by increased operational

Increased operational temperature increases thus among others the alkali steam partial pressure of sodium and potassium compounds exponentially, which is devastating for the ceramic interior lining of the reactor or cooling tubes depending on type of reaction vessel/gasifier. The outgoing fuel gas contains un-burni hydrocarbon compounds as well as sub-/ microscopic and -visual dust particles of heavier hydrocarbons (tars) and of alkali compounds. The part of alkaline dust particles increases with lower oxygen/fuel ratio - thus with black liquor of higher DS-content The amount of these alkaline dust particles is about 10 — 20 % of the mcoming alkali amount of the supplied black liquor. The dust particles are ^racticaUyϋmpossϊble to ffltraterThere are dust particles in size sub microscopic 0,01 - 0,20 μ, thus as particle size corresponding to tobacco-smoke - but also exists in size microscopic up to 20μ and above as visual. The gas turbine has requirements, which are set very high, regarding the cleanness of the fuel gas. The sensible light metal blades do not permit heavier hydrocarbons in the form of sticky tar particles, and concerning the alkali content Hie maximum permission by the gas turbine deliverer is only 1-10 ppb. A gas turbine based concept therefore requires extensive/expensive investments for elimination of the particular pollutions of the fuel gas. The gas turbine is also expensive, complicated and sensitive to load variations with the accompanying low efficiency owing to inferior performance of the turbine at partial load- One of the big advantages of the black liquor gasification vs. the recovery boiler is however the possibility, to a certain extent, to separate/split sodium and sulphur compounds between the melt and the gas phases during the reaction progress. The requirements of the gas turbine concept for black liquor of a high DS-content and for the gas turbine adjusted pressure of the preceding reaction process, mean however that the adaptability of the concept to fibre process requirements will be limited. This happens as the equilibrium reactions during the reaction progress in practice will be quite static. The calculated energy recovery of the combi concept at partial combustion of black liquor in reaction vessel is distributed as follows:

_* Power 21 %

* Steam production 50 % - Energy losses 29 %

When comparing with the established recovery boiler process the production of power is thus calculated to be about 15 % higher. Also the combi concept has as can be seen relatively great exergy losses. The application of black liquor of the combi concept has not yet left the concept stage and there is a certain hesitation within the pulping business — principally regarding the availability but also the complexity and the costs. Pressurized gasification of black liquor is unique in comparison with apparently similar processes and fuels. At present there are a number of process criteria, which are incompatible when trying to totally optimize the black liquor gasification. This recovery process therefore requires a totally new process design, an overall view, to avoid known difficulties and at the same time try to fulfil the process requirements of the delignification process and to make integration advantages with connected processes possible, for example black liquor evaporation with adherent partial processes- The pulping process including the recovery of chemicals and energy must be seen from a crosswise scientifically, overall perspective in order-to achieve the possible synergetic effects. The ultimate recovery forms the central axis around which the whole pulping process rotates comprising delignification, environmental considerations,, energy recovery from a liquid bio fuel and furthermore economy in the form of essentially power generation and operation availability with the possibility to design small scale plants. The following description of the present invention is exemplified by method and arrangement for recovering different forms of energy, and when appropriate also chemicals, from different types of fuels including different amounts of water, thus different steam partial pressures during the reaction progress in the reaction chamber with most of the exemplifications made by the many waste liquors of the pulping industry comprising as well sulphate pulp processes as occurring sulphite pulp processes of different basal chemistry — bases as sodium (Na), magnesium (Mg)₃ ammonium (NH4) and also calcium (Ca).

To conclude it is most encouraging, with regard to the variety of the present invention and the global energy situation that owing to the accelerating greenhouse problems, to state that for example in a modern pulping industry, from wood raw materiaWbio mass point of view, there is a potential to a four- or fivefold increase of the (electric) power recovery/generation. The comparison is made with the established recovery technology of today during an unchanged amount of supplied wood raw materiaL

BRIEF, GENERAL DESCRIPTION OF THE INVENTION

The present invention offers method and arrangement for recovering energy and when appropriate also chemicals, recovering chemicals including part or parts of: solid and/or molten material, sub-/microscoρic and visual dust particles, in solid and/or aqueous form and/or gaseous state, from a fuel comprising a pan or parts of: hydrogen, hydrocarbons and hydrogen compounds, by combustion/thermal decomposition during partial and/or total oxidation in at least one reaction chamber during at least one reaction progress above atmospheric pressure whereupon, produced gas, superheated or during partial or total moisture saturation, with content of chemical and/or physical energy is cooled and cleaned during condensation of into the gas vaporized agents and/or compounds, by expansion cooling through at least one expansion turbine during at least one partial step, when from the oxidation progress originating gas carried sub'/microscopic and visual dust particles, of sizes from around 0,0 lμ ate wetted by being condensation nuclei during the condensation, which ^"comprises as^" well (water-) steam as volatϋe^~orgafflc-agents. and compounds and volatile metals, when the weight of the dust particles increases and said particles are transferred from gas phase to liquid/condensate phase, which phases are separated by a separation device, simultaneously the content of physical energy during the expansion cooling is converted to power via a generator connected to the expander turbine, alternatively a turbine connection for operation of a stationary or mobile engine/vehicle - the latter on land, at sea or into the air. The partial pressure of the steam during the reaction progress is at least equivalent to the oxidation equivalence of the incorπing hydrogen, which preferably is increased by water additives with the incoming fuel, external condensate, returned condensate, oxidizing agent and/or steam additive direct into the reaction chamber, whereby the part of physical energy of the gas is increased correspondingly at the cost of the part of chemical energy. Water and/or steam can also be added to the gas phase after the reaction progress for partial or total moisture saturation at the present pressure. The water additive is most suitably composed by separated condensate after expansion cooling and is preferred to condensate from the first expansion cooling stage. When multi stage expansion cooling, with return of hot condensate, makes segregated condensate recovery possible with reference to as well flow, pressure, temperature and cleanness with the energy recovery during very high total isentropic efficiency. A preferred performance is made by the comparatively high steam partial pressure (HoO) during the reaction progress, which steam besides available oxygen (O₂) and carbon dioxide (CO₂), strengthen the oxidation potential of the progress. The steam reduces the partial pressure of the hydrocarbons and favours above all the final oxidation of the remaining hydrocarbon compounds during the final phase of the reaction process - some kind of steam reforming. Steam is in this respect 3 —4 times as efficient as for example carbon dioxide. When using fuels containing sulphur and alkali compounds the increased water content/steam during the oxidation progress has also a dramatic effect on the sulphur separation, which at partial oxidation is driven out with the gas phase as hydrogen sulphide (H₂S) and after the first gas combustion as sulphur dioxide (SO₂). The increased water content also reduces the flarne top temperatures during the reaction progress whereby the origin of thermal nitric oxide (NO_x) is radically reduced. As well fuel as air related nitrogen are thus counteracted to form nitric oxides and already formed nitric oxides can furthermore be converted to nitrogen gas (N₂) and steam by the injection of ammonia (NH3) or urea (Nt-fe^CO into the flue gas. The extraordinary nigh water evaporation enthalpy makes the evaporation to a very energy requiring process by the presence of hydrogen bindings which, connect the molecules. The water is therefore in this respect unique and more like a solid material than other liquids. The evaporarάorrof the -water during the initial reaction progress is by that-a heavy physical energy absorption, endotheπnic reaction, at the expense of the chemical energy part of the gas phase with the corresponding addition of the physical energy part of the gas phase — thus addition of the sensible and latent heat content of the gas. The water thus constitutes a most natural and effective energy carrier, acting dxrect between the sequences evaporation/energy reception and condensation/energy delivering without any efficiency restrictive influence on heat exchanger surfaces. By this an energy conversion, harmless to the environment, during minimum, of exergy losses, in the form of generated power or expander turbine connected transmission for operation of stationary or mobile machine is obtained. When appropriate, from the oxidation progress originating solid phase of some type of slag, melt, heavy metals and chemicals, this phase is separated after the reaction progress in a melt cooler/dissolver (so called quench) by water containing additives, preferable returned condensate. When operating case with a suitable gas amount for recovery from the gas phase, for example a sulphur compound, this is made by some form of selective proceeding, by means of for example alkali for H₂S and SO₂, within the suitable pressure and temperature area during and/or after the expansion cooling. When understoichiometric combustion of sulphur rich fuels takes place, the selective recovery of hydrogen sulphide (EbS) is made possible, whereupon the H₂S constitutes a raw material for a diversified preparation of a number of chemicals. When presence of remaining chemical energy in the gas phase, this gas is fully combusted in another/second reaction chamber within the expansion cooling sequence or fully combusted in a gas boiler or correspondingly_;, when appropriate with subsequent alternative recovery of suitable amount of gas — for example sulphur dioxide (SO^)- It is possible to use flue gas condensation for preheating of suitable media, whereby the discharge gas, at the absence of air as oxidizing agent m principle contains only carbon dioxide (CO₂) - suitable for recovery/utilization by being liquefied for other markets or long time storing/final waste disposal. The gas combustion can be supported

chamber or gas boiler, the latter used for preheating of the fαel for the reaction progress, oxidizing agent and heating of gas and/or liquid phase in connection with the expansion cooling process - everything to increase the physical energy level of the system - or for customary steam production with or without a steam turbine with adherent generator for power generation. The principal characteristics of the present invention and the direct key function are thus the conditions/possϊbϊlϊties around the high water steam partial pressure during the reaction progress comprising as well process chemistry as the energy recovery. The application of the present invention within among others the combined power and heating plants^~aDd"the chemical and^~energyτecoveryof liquors within the-pulping industry forms a sharp contrast to the technology state of the art and is a substantial breakthrough — a great technique leap. Principal diagrams according to figures 1 and 2 describe the present invention in a comprehensive form, with condensate recirculation, as some form of "energy pinwheel". hi general there are no necessary transport pumps shown in any of the subsequent figures. -

DETAILED DESCRIPTION OF THE INVENTION

Figure 1:

Dry fuel 30 is added to an internal, recycling condensate flow 32 with reaction progress in the reaction chamber 1 during total oxidation by alternative oxidizing agents.

Figure 2:

Water containing fuel 31/30 is added to an internal, recycling condensate flow 32 - forming a part of the total amount of condensate — with reaction progress in a reaction chamber 1 during partial oxidation by alternative oxidmng agents and terrniπal combustion of produced fuel gas.

ID general, the apparatus and piping of these both figures constitute in applicable parts of reaction chamber 1, expansion cooling turbine 2 with energy recovery hi the form of generated power 20 via generator 3 and/or power transmission, mechanical or hydraulic, for operation of stationary S or mobile engine 83 A, separation device for gas/condensate 14, secondary combustion chamber of fuel gas by gas boiler 12 with the possibility of heating recycling condensate and/or gas before the turbine expander and production of steam 89 via feed water 88_; dry fuel 30, fuel carried water 31₅ to reaction chamber recycling condensate 32, expansion cooled clean condensate excess 34, gas before expander 38, gas after expander 39.

consisting of carbon dioxide (COa) and steam possibly with the contribution of inert nitrogen (N₂) originating from the fuel ox air additives. When operation case according to figure 1 comprising a dry fuel 3O₇ in the form of gaseous hydrocarbon compounds, at total oxidation with stoichiometric combustion the temperature level around 1800⁰C is obtained with air 35 as an oxidizing agent and just above 3000⁰C with oxygen 36 as an oxidizing agent, which temperature levels are reduced in relation to the amount of added water/recycling condensate 32 by the endothermic vaporizaα^'oa work, which is recovered during the condensation in the ^" expansion turbiπfe-stage 2 in^" the fomrof power 20^~and/or mechanical or ^"hydraulic operation o] stationary or mobile machine during an absolute minirnum of exergy losses. During the reaction/oxidation progress also an amount of steam equivalent with the hydrogen content of the foel is formed, and this strengthens the steam partial pressure and the physical energy level of the gas. When air is used as an oxidizing agent, a small moisture amount is also addec in this way to the reaction progress.

Figure 3:

The principle for the progress of the expansion cooling and energy recovering by means of expander turbine can be seen of the enthalpy/entropy diagram (TS diagram.) according to present figure.

The subsequent operation examples, figures 4 -25, illustrate the variety of the present invention but are not meant to limit its extent but can be varied or combined within the scope of the patent claims. Below can be seen process diagrams/figures 4 and 5 of more common direction.

Figure 4:

Dry fuel 30 and recycling condensate 32 and turbo compressed air 35 as oxidizing agent are added to the reaction progress during total oxidation. From the reaction chamber 1 outgoing pressurized flue gas, superheated or during partial or total moisture saturation, connects via piping 38 the expansion cooling turbine 2 connected with turbo compressor 8 and the generator 3 for power generation 20 alternatively with common power transmission in the form of mechanical or hydraulic device for operation of stationary or mobile machine 83 A — the later for some form of transport/ vehicle. From the expansion cooling turbine outgoing gas

condensate flow 32. The ouilet/counter-pressure of the expansion cooling turbine settles the temperature of the gas/condensate mixture with outlet pressure preferably lower than atmospheric pressure, thus a negative pressure/vacuum. According to this figure processes around atmospheric pressure are aimed at Heavy metals, non. process elements (NPE), soot, ashes and slag originating from the reaction progress are separated by means of separation device 18. The recycling condensate flow 32 contains earlier vaporized water, volatile organic substances and compounds, volatile metals/heavy metals (NPE) and earlier gas carried sub-Vmicroscopic and visual dust particles- which dust particles are wetted during the "CDndeπsatiorrprogress of the ^"expansion- cooling by foτming-cσndensa-ion' nuclei whereupon the dust particles get heavier and are transferred to liquid phase 32, with return to the reaction chamber 1 via the incoming fuel and for moistening of outgoing flue gas 38 and a small flow for the cooling and separation device for solid phase 18. This small condensate flow prevents simultaneous building up of NPE in the system. The gas flow 44 thereafter connects suitable apparatus for recovery of the remaining, small heat content of the flue gas by for example flue gas condensation 22 with subsequent, alternatively placed earlier, fen 13 with flue gas outlet 45. The flue gas discharge 45 is composed by in principle only carbon dioxide (CO₂), which can be utilized by compression and condensation - liquefying pressure 16 bar — and utilized on various markets or as a final waste disposal down in suitable ground - for example in aquifers. If carbon dioxide in principle is required without any content of nitrogeD/nitrogen compounds, compressed air 35 is suitably replaced by oxygen 36.

Figure 5:

The figure corresponds as a principle to the preceding figure 4, however with the exception that the fuel contains water and the procedure comprising expansion cooling in three stages- Fuel 30 with water content 31 and recycling condensate 32 and 33 with turbo compressed air 35 as oxidizing agent are added to the reaction, chamber 1 for reaction progress during total or partial oxidation. Alternative oxidizing agents or in combination with each other are used, as oxygen (Oo) 36 and/or a hydrogen peroxide solution (H₂O₂) 37. From reaction chamber 1 outgoing gas, superheated or during partial or total moisture saturation, connects by piping 38 the expansion cooling turbine 2 connected to turbo compressor 8 and generator 3 for power generation 20. The discharge 39 from the expansion cooling turbine 2 connects device 14 for separation of condensate phase 32 from gas phase 40, which connects the next expansion cooling turbine ⁴ connected xo generator 5 for generation of more power 20. From the

phase 33 from, gas phase 42_ which connects die next expansion cooling turbine 6 connected to generator 7 for further generation of power 20. If it is suitable to use some of the expander turbines for mechanical or hydraulic transferred operation of stationary or mobile machines, this is a possible alternative - the former for example corresponding to turbo compressor 8. From the expansion cooling turbine 6 outgoing flow 43 connects device 16 for separation of condensate phase 34 from gas phase 44, which connects at least one liquid ring pump 9₅ ox another device with the corresponding function, in order to together with the condensation effect and vacuum pump 10 with or without barometric condensate 34 fall leg with water-seal create predetermined negative pressure/vacnumiit the end ofthe-aystem-^rTien-gas piping 44 connects separation device 17 for separation of cooling and sealing liquid 24 for liquid ring pump 9 and whereupon the gas flow is pressure increased via at least one fan 11 before gas outlet 45 regarding reaction progress during total oxidation in reaction vessel L The high steam partial pressure of the reaction progress counteracts the formation of nitric oxides (NO_*) in the flue gas by a counteraction of uncontrolled- high temperature level. It is also possible to eliminate already formed nitrogen oxides by injection, 40N₅ of ammonia (NH₃), and/or urea (NEb^CO into the flue gas ID one or more places, preferably before expander tuxbine stage. By doing this the nitric oxides will be converted chemically to nitrogen (N₂) and water. The flue gas. by this, gets an increased steam partial pressure, which further increases the physical energy content of the flue gas. At reaction progresses during partial oxidation in the reaction chamber 1, a fuel gas 44 is obtained, which according to the dashed proceeding in the figure, is combusted in gas boiler 12 with possible adding fuel 21, with production of high pressure steam 89, in one with the expander turbine process integrated performance, and operation of steam turbine 120 with generator 121 for further power generation 20 and via separation device 17D recirculation of condensate 88, alternatively with suitable pre-heating according to 12A and 12B of the condensate flows 32 and/or 33. After gas boiler 12 a gas fan 13 is preferably installed. The pre-heating can also include gas flows before respective expander stage —the latter cannot be seen in the figure. The procedure thus comprises expansion cooled, clean condensate excess 34 from cistern 19 and is separated for example within the temperature 18-20⁰C corresponding to the pressure level 0,03 bar (a) after expansion cooling turbine 6- The low temperature level of the condensate excess 34, without any need of cooling water and by that at a minimum of exergy losses, generates correspondingly more power 20 via generator 7 connected to expansion cooling turbine 6, which is the Third and last expansion cooling stage. Expander turbine stages 2, 4 and ό of tbe

condensate separation 14, 15 and 16 after respective expander stage or partial stage. If steam production or district heating 23 is required, steam generator or heat exchanger is installed on recycling condensate flow 33₇ or other suitable place, with correspondingly lower power generation 20 as a result

Figure 6:

The proceeding according to the present figure is essentially well suited for some form of district heating plant suitable for some form, of quarter of a town or bigger population centre ^"and^"3e^cribesxombustiou^"xinder totahoxidation of dry delivered, or almost dry delivered, fuel under pressurized reaction progress in reaction chamber 1. The reaction process can be catalysed by addition of hydrogen peroxide solution (H2O₂) 37, whereupon as well the water steam partial pressure as the physical energy part is increased correspondingly. The gas flows 38, 40 and 42 pass respective cooling expansion stage 2, 4 and 6 with the intermediate devices for separation of respective condensate flows 32, 33 and 34, All the cooling expansion stages and the turbo compressor 8 and generator 3 are connected to a common rotating system. In principal all the recycling condensate flows 32, 33 and 34 are returned to the reaction chamber 1. Condensation flow 33, when necessary also a part of condensate flow 32₇ is previously used for district heating 23 with used energy amount adjusted according to needs corresponding to the reduced part of power generation 20. There is a possibility not to utilize the district heating system 23, for example during the summertime, with, the accompanying more power generation 20- When excess of power generation 20 this part is fed into the common network. The water refilling or drainage of the system is done by the cooling and sealing water 24 of the liquid ring pump 9 according to the level control 19A at the storage tank 19. When there is water excess in the system the drainage is thus made through the "cold" end. The outgoing flue gas 45 is fiee from all forms of dust particles, volatile metals and volatile organic substances and compounds. The formation of nitric oxides as thermal NO_x is counteracted by the high steam partial pressure of the reaction progress. The high total isentropic efficiency makes exceptionally high energy recovery possible by the return of heat condensates and the heat ttansmissioα acting direct by the different phases of water as some kind of energy transducer, with, a continuing condensation from the very high temperature of the reaction progress down to the outgoing expansion cold flue gas at room temperature.

Figure 7:

comprising a first fuel 30 and a second 3OC. possibly with content of water 31 a^d 3ic respectively during pressurized reaction progresses in the reaction vessel 1 and 1C during partial and total oxidation respectively by means of additions of compressed air 35 and 35C as oxidizing agents by turbo compressor 8 and additives of recovered chemicals 401 and 401C by one or more processes, 400 and 400C respectively, while the remaining amount of the recovered chemicals is brought out of the proceeding. Depending on type of fuels, with different chemicals content after the reaction progresses a phase of solid and/or molten material 18 and 18C respectively can be obtained. The outgoing gas phase 38 and 38C - respectively- of the-reaction-chambeϊs are cooled during condensation-of in- the gas vaporized substances and compounds by expansion cooling. The mentioned gas phases contain fine particular dust which is wetted during the condensation and gets heavier and falls out mainly in the condensate flow 32 and 32 C of respective first stage. Both these condensate flows are returned to respective reaction chamber. Both the oxidation progresses, partial respective total, follow each other with common expansion cooling down to negative pressure/vacuum, for example 0,03 bar (a) with corresponding temperature level 18-20^ϋC. Each expansion turbine is connected to a generator for power generation 20. The proceeding has extremely low exergy losses, by expansion turbines connected in series with recirculation of energy rich condensate flows with the recovery of as well the heat content as the pressure energy and with outlet of expansion cooled excess condensate at very low temperature- The recovery of mentioned chemicals 401 and 401C from respective gas phase is thus made by a first process stage 400 in reducing state and by a second process stage 400C in oxidizing state. Within the reducing state the content of the fuel gas of for example hydrogen (H₂) and carbon, monoxide (CO) are recovered, according to known procedure, constituting synthesis gas as raw material for the production of for example hydrogen peroxide solution (H₂O₂) and/or a number of different mobile motor fuels. There are, when fuel 30 containing sulphur, further possibilities tor recovering chemicals from the reducing gas according to later described proceedings under chapter The sulphur handling hi the- form of hydrogen sulphide (H₂S), elementary sulphur (S), hydrogen (H₂) and hydrogen peroxide (H₂O₂) as a whole or parts of it. Within the oxidizing state for example the content of the flue gas of sulphur dioxide (SO₂) is extracted by means of absorption by external and/or by the fuel added aUkali according to later presented proceeding for the production of sulphite liquors (NazSOs / >IaHSθ3) for the production of sulphite based pulping qualities. Some fuels contain slag forming substances and compounds which are separated as a phase of solid and/or molten material 18 which is cooled and/or

superheated or during partial or total moisture saturation, connects expansion cooling turbine 2 connected to turbo compressor 8. From expansion cooling turbine 2 outgoing flow 39 connects device 14 for separation of condensate phase 32 from gas phase 40 whereupon condensate phase 32 is returned to reaction vessel 1, witia partial flows for moistening from reaction vessel 1 outgoing gas 38 and when needed for the treatment of phase of solid and/or molten material 18 at quench 126. Gas phase 40 connects one or more processes 400 for recovering chemicals 401 whereupon the remaining part of the gas phase 402 connects the next expansion cooling turbine stage 4. From the expansion cooling turbine 4 outgoing flow 41 connects-device 15 forseparation of-eβndensate-phase-33-fi-om gas-phase-42, whereupon condensate phase 33 connects condensate phase 32 for common return to reaction chamber 1. The rest of the gas phase 42 is after that totally combusted by a pressurized reaction progress in reaction chamber 1C during addition of compressed aix 35C and fuel 30C, possibly with water content 31C and part of earlier recovered chemicals 401. whereupon outgoing gas 38C, superheated or during partial or total moisture saturation, connects the expansion cooling turbine 2C. From the expansion cooling turbine 2C outgoing flow 39C connects device 14C for separation of condensate phase 32C from gas phase 4OC whereupon condensate phase 32C is returned to reaction chamber 1C. When there is unbalance between the condensate fractions 32, 33 and 32C, there is a mutual exchange of condensate through flow 33/32C. From the gas phase 4OC one or more chemicals 401 C are recovered whereupon the remaining gas flow connects expansion cooling turbine 4C. From this turbine 4C outgoing flow 41C connects device 15C for separation of the expansion cooled, clean condensate excess 34 from the gas phase 42C, whereupon said gas phase strengthens the negative pressure/vacuum achieved by the condensation effect of the proceeding and by the barometric condensate fall leg with water-seal 34 and vacuum pump 10 and liquid ring pump 9 with the cooling and sealing liquid 24, which is separated by device 17 whereupon the expansion cooled gas phase 45 is pressure increased by gas fan 11 before the outlet through funnel.

Figure 8:

The proceeding according to this figure describes, like the preceding figure 7, a form of two stage combustion comprising a fuel 30A containing a liquid possible for vaporization, preferably water 3 IA, with the additive of a supporting fuel 30B which fuels are commonly combusted during pressurized reaction progress in the reaction vessel 1 during partial oxidation by addition of compressed air 35 as oxidizing agent through turbo compressor 8.

recovery of actual agents and/or compounds comprising heavy metals. In order to facilitate an almost complete recovery the two stage combustion with a first stage during partial oxidation is used whereupon follows a second stage under total oxidation of the fuel gas of the first stage with the turbine expansion cooling of gas flow after respective reaction progress and recycling/separation of respective condensate flow. The proceeding makes fractionated three stage separation possible of actual agents and/or compounds, regarding as well the oxidation potential as the pressure and temperature:

• Separation stage I — 18 A — is composed by ash and/or a phase of solid and/oτ molten material and/or heavy metals 18A during high temperature-and reducing state.

• Separation stage II - 18B — is composed by condensate containing earlier gas carried dust particles and/or volatile agents and/or compounds comprising heavy metals during somewhat lower pressure and temperature compared to separation stage I but still during reducing state.

• Separation stage IH - 1 SC — is composed by condensate mainly containing the rest of earlier volatile agents and/or compounds comprising heavy metals during even lower pressure and temperature compared to separation stage II and furthermore during oxidizing slate.

From reaction chamber 1 outgoing fuel gas 38 of high pressure, superheated or during partial or total moisture saturation, is connected to expansion cooling turbine 2 with connection to air compressor 8 and generator 3 for power generation 20- From the expansion cooling turbine 2 outgoing flow 39 connects the device 14 for separation of condensate phase 32 from gas phase 40 whereupon condensate phase 32 is returned to reaction chamber 1, with a partial flow for moistening of from the reaction chamber 1 outgoing fuel gas 38 and, when needed, for treatment of ash and/or a phase of solid and/or molten material 18 A at quench 126. The fuel gas phase 40 connects reaction chamber 1C for complete combustion during total oxidation, whereupon outgoing flue gas 38C, superheated or during partial or moisture saturation, is connected to expansion cooling turbine 2C with adherent generator 3C for power generation 20. From the expansion, cooling turbine 2C leaving flow 39C connects device 15 for separation of condensate phase 32C fjrom gas phase 40C whereupon condensate phase 32C is returned to reaction chamber 1C with partial flows for moistening from reaction chamber 1 C outgoing flue gas 38C and with connection to condensate phase 32. Gas phase 40C connects the expansion cooling turbine 4C with adherent generatoT 5C for power generation 20. From the expansion cooling turbine 4C outgoing flow 41C is connected to

42C, whereupon said gas phase 42C strengthens the negative pressure/vacuum achieved by the condensation effect of the proceeding and by barometric condensate fall leg with water- seal and vacuum pump 10 as well as by liquid ring pump 9, as a whole or parts thereof, with the cooling and sealing liquid 24/34 which is separated by device 17 whereupon the gas phase 45, in principal consists of carbon dioxide (CO2) and the inert nitrogen (N₂) originating from the combustion air, is some pressure increased by gas fan 11 before the outlet through funneJ. Back to separation device 14 and outgoing condensate phase 32 with separation of a partial flow 32A-, which partial flow is pressure reduced through a liquid expander 80 with adherent generator-81 for power generation 20 - alternatively a pressure reducing valve - with connection of outgoing flow to device 85 for separation of the condensate phase 18B from, the expansion steam 180, which steam flow is connected to earlier mentioned flow 39C before connection to separation device 15. This figure thus describes fractionated recovery, during as well reducing as oxidizing conditions within the same proceeding, through stages 18A, 18B and 18C respectively mainly of different types of hazardous waste for example combustion/cremation under high pressure/steam partial pressure, whereupon heavy metals as for example quicksilver (Hg), dust particles and the formaldehyde content of the fibreboard coffins are prevented from entering into the atmosphere - while the energy from all the fuels is essentially recovered as power 20. Selenium (Se) 300 can also be added to one or both the reaction progresses in order to bind the quicksilver, whereupon the selenium, as a part or the whole, is recycled with the condensate flow 32 and 32C respectively.

Figure 9:

This application of the expander turbine proceeding is essentially well suited within the transport sector. The proceeding is exemplified by expansion cooling in two stages with fuel nearly free from carbon (C) or carbon compounds, whereby the discharge in principle exists of only water/condensate, besides when addition of compressed air the discharge also includes the air content of inert nitrogen (N₂)- Reaction chamber 1, with pressurized reaction progress during total oxidation, is fed with fuel and oxidizing agents comprising part of parts of: hydrogen peroxide (H₂O₂) 37, constitutes an integrated form of fuel and oxidising agent, or as hydrogen peroxide solution (H₂Q₂ * nJi^O) 37₃ hydrogen (Hb) 68, oxygen (O₂) 36, turbo compressed air 35, ozone (O₃) 115 according to one or more of the equilibrium/decomposition reactions below:

3/2Q₂ + 4EDj + H2O2 * TiH₂O <^> (5+n)H2θ comprising added compressed air/oxygen.

O3 <z> O2 + O, representing one of the possibilities to add oxygen (and physical energy) Hydrogen peroxide 37 has a huge thermodynamic energy content, which means that huge amounts of energy are released when peroxide decomposition during Hie reaction progress. Furthermore hydroxide radicals are formed, which give an efficient and even combustion at comparatively low temperature. There is also a possibility to render more effective and to pressurize the reaction progress by adding some form of activator 30 in order to increase the decomposition reaction rate of the-hydrogen peroxide,- even- though the hydrogen peroxide naturally has a great instability. The burner system m reaction chamber 1 consists preferably of at least one venture-nozzle for actual additive flows. During the reaction progress produced steam flow (5+n)H₂O 38, superheated or during partial or total moisture saturation, is cooled during steam condensation by expansion cooling through expander turbines 2 and 4, simultaneously as the steam flow content of physical energy is transformed to mechanical work via expander turbine connected turbo compressor 8 and generator 3 with possibility to reversing at start up and generating of within the process needed power 20. among others for charging the storage battery/accumulator 3 A and for operation of pumps, fan etc. and power transmission including hydraulics with shaft-coupling 83B and gear 83C for operation of mobile engine/vehicle 83 A. Alternatively (can not be seen in figure) a fuel cell process for the production of electricity 20 is integrated and with pressurized fuel cell also integration/conDection of steam to expander. The outgoing steam/condensate flow 39 of the expansion turbme 2 is connected to device 14 for separation of condensate flow 32 from the remaining steam flow 40. The recycling condensate 32- comprising of among others the water content (nU₂θ) of the hydrogen peroxide solution 37 and the by equilibrium formed steam (5+n)H₂θ, control the intensity of the reaction progress and thereby the water thus constitutes some kind of modulator with among others limited NOx-forcπation. The exothermic reaction heat of the reaction progress and the endotherroic vaporizing work is by that balanced with, regard to the "ultimate energy recovery in connection with the turbine expansion cooling. Both the water additives as well as by the equilibrium formed amount of steam during the reaction progress thus increase the total amount of steam and by that also the physical energy level of the system. Earlier mentioned, possible addition of activator/catalyst 30 is recycled to a certain extent with condensate flow 32. Back to the remaining steam flow 40 which is connected to the next expansion turbine 4 constitutes the last expansion cooling stage. The

maintainiαg necessary negative pressure/vacuum at the end of the system, besides through the condensation effect, by means of fluid ring pomp 9 -with internally cooled condensate 34 forming cooling and sealing liquid 24/34, which is separated/recycled via separation device 17, further connecting for increased condensation effect, a number of heat exchangers/vaporizers 36B, 37B, 68B and 1J5B for according to mentioned above, alternative fuel/oxidation additions as oxygen 36., hydrogen peroxide 37- hydrogen 68 and ozone 115 from respective tanks 36A, 37A,68A and 115 A. These tanks are preferably pressurized, with preferred content of liquefied gas and isolated. Hydrogen H₂ 68 is kept cool in the tank 68 A ^■ whereupon the subsequent vaporizer 68B, also comprising -a cooler for liquid hydrogen in the tank 68A- The cooling capacity of the heat exchangers/vaporizers at flow 41 with the ending liquid ring pump 9, thus creates a predetermined negative pressure/vacuum — for example at the discharge pressure/counter-pressure 0,05 bar (a) of the expander turbine 4 the corresponding temperature is around 23°C, comprising the rest condensate. After the separation device 17, when needed, fan 11 is installed in piping 45 for discharge of start up steam. There is a possibility, into the air/oxygen flow O₂ direct initiate a certain amount of ozone O₃ by the supply of electrical energy or ultraviolet radiation 1 15C, or other known proceedings, when the system 115A/115B for supplying ozone can be a complementary or excluded. Preferably the reaction progress into the reaction chamber 1 is pressurized by the exothermic reaction progress of the additives, comprising its decomposition reactions, and by the endothermic evaporation of the water/condensate as an effective process modulator,

TJt e sulphur handling

A real technological breakthrough is according to the present invention the possibility of the proceeding to separate from a fuel almost all of the sulphur content in reduced form as hydrogen sulphide (H₂S) as a raw material for diversified further production of hydrogen (H₂), hydrogen peroxide (H₂O₂) and elementary sulphur (S)- The recovery of hydrogen sulphide from a gas can be made by allowing the gas to pass a gas washing apparatus for selective and regenerative absorption of the HaS-content according to known procedure. Examples of such absorption processes are the Purisol process which utilizes N- rnethylpyrrolidone as an absorption liquid, and the Dow Gas/Spec-process which utilizes methyldiethylamine (MDEA) as the absorption agent The utilization of hydrogen sulphide as a raw material can be made by reversible thermal decomposition during heating above _temperature 300⁰C₅ preferably by one with the recovered liquid sulphur counter-currently

or recovery of sulphur in elementary form according to H₂S <-> H₂ + S

The recovery and decomposition of hydrogen sulphide direct from a gas containing hydrogen sulphide is possible through a, preferably pressurized, anthraquinone (AQ)/antrahydτoquinone (AHQ)-proceeding according to principle diagram, figure 10. Hydrogen H₂ can be used, besides present invention- also within the petoleurn/refining industry, to fuel cells — preferably pressurized - or for further production according to below. There are also possibilities for further production of for example ammonia (NH^) and dimethyl ether (DME) andinetfr-inol (CHsOBQ or othermobϊle fuels; At recovering these products-from bio fuels — for example waste/spent liquors when chemical pulp production - so called "green" mobile fuels is obtained with the expansion cooling proceeding as a preceding gas cleaning and power generation stage. Elementary sulphur or polysulfide can be used according to later exemplifications.

The company Marathon Oil Co, USA has developed the so called Hysulf-process for the conversion of H2S to H₂ and S as partial replacement for the so called Claus process. The company also describes the possibility to produce as an alternative to H₂ instead produce O₂ via an H₂O₂ -intermediate stage. Marathon Oil Co's patent document US 4, 581,128 describes in no way the possibility/purpose to produce hydrogen peroxide. The Hysulf-process is similar to customary processes for the production of hydrogen peroxide by the utilization of reaction of anthraquinone (AQ) to anthrahydroquinone (AHQ), followed by the regeneration stage AHQ to AQ. The hydrogen gas formation according to the Hysulf-process is made by catalytic dehydro generation. Conventionally almost all H₂O₂ in the world is produced by the anthraquiDone method - the AQ-method. The reaction is done by stepwise hydro generation and oxidation of alkyl anthraquinones when hydrogen peroxide is formed. The possibility to use anthraquinone according to present invention also means absorbing of hydrogen sulphide direct from for example fuel gas for the production of elementary sulphur, hydrogen and/or hydrogen peroxide according to principal diagram, figure 10, with integration of the sulphate pulp process according to block diagram, figure 11. This figure describes the possibility to co¬ ordinate a preferably pressurized AQ handling with the sulphate pulp cooking and the chemical recovery by a part of nearly sulphide free white liquor or low sulphidity white liquor receiving "used" AQ with new charge/refill to the recovery for necessary renewal. Recovered elementary sulphur is added to the remaining part of low sulphidity white liquor for the production of pulp yield increasing poly sulphide solution (S_x ^2-) according to:

Detailed description is following ϊn figures 10 and 11. Figure 10:

Pressurized gas 4OA containing H₂S is fed to a reaction chamber 61 where the anthraquinone (AQ) is transformed to anthrahydroquinone (AHQ). A subsequent separation stage 62 separates elementary sulphur (S) 69. A regeneration stage 63 reforms the anthraquinone (AQ). After the separation stage 64 the anthraquinone solution 65 is recycled to the reaction stage 61 for further one, preferably pressurized sequence, and so on. During the second separation - stage 64- axe delivered, besides the gas 4OB freed-from hydrogen sulphide (H₂S), also hydrogen (H₂) 68 and / or (H2Q2) 37. The hydrogen 68 formation requires a catalytic dehydτo generation - which is not shown in the figure. Hydrogen peroxide (H₂O₂) 37 is formed through oxidation by oxygen containing agent — for example air 35 and/or oxygen (O₂) 36.

Figure 11:

This figure comprises application of method according to figure 10 within the sulphate process of the pulp industry with process integration of the pulp production and the chemical recovery. Waste liquor/release liquor from sulphate pulp digester 50 passes DS-increasing process stage - preferably evaporation plant — however not shown in figure - whereupon DS- arnount 30 with remaining water content 31, also named black liquor, connects one or more reaction chambers 1 together with compressed air 35 for reaction progress during partial oxidation. From the reaction chamber outgoing fuel gas 38 passes a first expansion cooling turbine stage 59 with power 20 generation, whereupon outgoing fuel gas connects the process stage, according to figure 10, for decomposition of the H2S part. Recycled condensate 32 from the expansion stage connects reaction chamber 1 as a whole or as a partial flow. Fuel gas 4OB, treated regarding H₂S, passes a second expansion cooling turbine stage 60 for farther power 20 generation- Separated condensate 33 containing dissolved carbon dioxide (somewhat lower pH) is used for improved pulp 53 washing. As the principal part of the sulphur content of the black liquor is driven out with the fuel gas as HzS, the melt phase 18 from the reaction progress contains mainly sodium carbonate (Na2CO₃) and sodium hydroxide (NaOH) with a strongly restricted amount of sodium sulphide (Na₂S). This means that from reaction chamber 1 leaving green liquor 18 constitutes nearly sulphide free green liquor. Non process elements (NPE) are eliminated by a sludge filter and nearly sulphide free green liquor is causticised 51 whereupon part of nearly sulphide free white liquor 55 is mixed with elementary sulphur 69

sulphate pulping process. Aa advantage at causticising 51 cf nearly sulphide free green liquor 18, for production of nearly sulphide free white liquor 55, is the low part of sulphide (NaHS) whereby fhe causύfication degree will be higher by changing the ion strength relation positively. The remaining part of nearly sulphide free white liquor 55 is mixed with the exchange part of recycled antraquinoDe solution (AQ) 65 into mixer 70 whereupon the cooking solution 56 connects the final part of the pulp cooking. Refill is evident from the flow of antraquinone solution (AQ) 67. Further a possibility to direct produce cooking liquor 56 is to add, as a part of or as a whole, exchanged recycled AQ solution 65 into mixer 70 and nearly- sulphide free-green tiquor-18A - broken Ene-in figure.- Produced hydrogen peroxide (H₂O₂) 37 is used for pulp bleaching and/or as an oxidizing agent/fuel in the reaction chamber 1. The arrangement after the expander turbine stage 60 comprises negative pressure/vacuum generation equipment as well as combustion of fuel gas 40B and cannot be seen in figure 11 but is valid according to the following figure 12.

Figure 12:

The figure further describes a proceeding regarding the utilization of the present invention - among others an almost total separation of alkali and sulphur - and the possibility for only causticising of a small partial flow of nearly sulphide free green liquor. Parts of the positioning used can be found in the earlier text for figure 11. When gasification, partial oxidation, of waste liquors from the pulping industry two different kinds of reaction progresses with separate reaction chambers, IA and IB respectively, are used composed of at least one chamber of each during quite different process criteria. A first reaction vessel IA worts according to the most preferable carrying out of this invention for among others separation / split of alkali and sulphur while the second reaction stage 1 B works during quite different, "opposite", criteria as low process pressure, preferably 1,10 - 4,00 bar (a), with low steam partial pressure, preferably 0,20 - 0,95 bar (a) and within the temperature interval 920 — 1000⁰C with supplying recovered elementary sulphur (S) 69 for direct conversion/production of high sulphidity white liquor (Na₂S) by displaced reaction equilibrium during the reaction progress in the second reaction chamber IB according to:

Na₂CO₃ + H₂S <=> Na₂S + H₂O + CO₂

Supplied internally recovered, elementary sulphur S 69 Is during reaction progress reduced to hydrogen sulphide (H₂S) with subsequent equilibrium displacement according to above towards right. By that means high sulphidity white liquor is direct produced without any need.

proceeding according to the present figure. Earlier described proceedings to use K₂S as a raw material for further production according to figures 10 and 11 are included in applicable parts in this figure 12. Reaction chamber IA thus works during operation criteria for the separation/split of alkali and sulphur with the later as H₂S in the fuel gas 38A- Reaction chamber IB thus during quite different operation criteria, according to above, and the quite decisive supplying of internal within the process recovered elementary sulphur (S) 69. In this way the dominating part of sulphur is displayed to the melt phase of the second reaction stage in the form of sodium sulphide (NaaS) ISB. The remaining sulphur is to be found in gas phase -38-B-Bs-H₂S, -therefore the gas phase is eompressed in turbo compressor 82, with in-tapping to expansion turbine 2 which is also fed with fuel gas 38A from reaction chamber IA. From the expansion turbine 2 outgoing flow 39 contains by that as well gas phase 38 A as 38B and is connected to separation device 14. Here the gas/liquid phase 39 is separated with gas phase 40 fed to the next expansion cooling turbine 4 whereupon the outgoing flow 41 is connected to separation device 15. Here the gas phase 42 and condensate phase 33 with partial flow 33 A is separated which together with condensate phase 32, with the content of among others earlier vaporized hydrocarbon compounds and gas carried dust particles, from the preceding separation device 14 is added to reaction chamber IA with adherent melt dissolver 126A as one or more partial flows — among others flow 321 to the preparing evaporation plant and for moistening from reaction chamber outgoing fuel gas 38A. Reaction chamber IA is feed black liquor with the DS-content 30 and water content 31 and when appropriate also bleach plant effluent 87. There is also a possibility to add hydrogen peroxide (H₂O₂) to reaction chamber IA and IB as a both fuel and oxidizing agent. The normal case for oxidising agent corresponds to oxygen 36 to reaction chamber IA and by high pressure fan 84 for air 35B to reaction chamber IB- Back to separation device 15 with the subsequent gas phase 42 and condensate phase 33 with partial flow 33 A according to above and a partial flow 33B to reaction chamber IB with adherent melt dissolver 126B. The condensate recovery is segregated and the conditions for process integration are controlling the water balance. When excess of condensate phase 33 the condensate .86 is used for example for pulp washing. Back to gas phase 42 with content of H₂S, among others from the collected "heavy" gas system, non condensable gas (NCG) 90 of the mill, which is connected to device 61-64 for the decomposition/split of H₂$ according to earlier described proceedings. Back to reaction chamber IA with outgoing, pressurized green liquor flow 18A of almost sulphide free alkali or low sulphide alkali, which is depressurized, foi example by a liquid expander 80 with or

ISA and expansion steam are separated through separation device 85. Green liquor ISA is treated with pressure filter 95 for the separation of non process elements (NPE) 54 before the caustϋϋcation plant 51 for production of nearly sulphide free white liquor or low sulfidity white liquor 55. When need of nearly sulphide free green liquor 18 A, according to figure 11 , a partial flow is drawn off before causticising 51 with direct production of cooking liquor 56 by adding in mixer 70 the exchange amount of recycled AQ-solutLoB 65 together with nearly sulphide free green liquor 18A - all according to figure 11. From the device 61 -64 for decomposition of H₂S, partial flows of H₂ 68, H2O₂ 37, and S 69 and when appropriate the -ftow-AQ 65 is leaving. The hydrogen fraction 68 can at-the expense of the peroxide production (H₂O₂) 37 be further refined in another way according to earlier description. After the removal of the HaS-content of the fuel gas the gas flow is expansion cooled by a third expansion turbine stage 6. All three expander stages are provided with generators 3, 5 and 7 for power 20 generation, alternatively with expanders' power transmission for operation of engine / machine. The first expander stage 2 is furthermore provided with start up function for the turbo compressor 82 in the form of an electric motor 83. The gas flow 43 after the third and last turbine stage 6 connects separation device 16 with separation of gas phase 44 and liquid phase 34. The counter-pressure for the expander turbine 6 is quite decisive for the outlet temperature of gas respective liquid phase/excess condensate 34. When for example the outlet pressure 0,05 bar (a) the corresponding outlet temperature around 23°C is obtained- The very low temperature/pressure level of the leaving flow from the last expansion cooling stage 6 lowers in the corresponding way the exergi losses and increases the generation of power 20. The negative pressure/vacuum of the system after the last expansion cooling stage is supported, besides the condensation effect itself, by some suitable process technology as liquid ring pump 9, fan 11 and by barometric condensate 34 fall leg with water-seal and vacuum pump 10 as a whole or parts thereof, and storage tank 19 for cooled, clean re-useable condensate excess 34. The gas phase system 44 is co-ordinated with from the evaporation plant originating NCG-system 90. When needed, a system of liquid ring pumps connected in series, is used and when the cooling and sealing liquid 24 suitably is led in counter-current to the gas direction for stepwise gas washing. The cooling and sealing liquid can also be made of an alkaline liquid 24A, 55 for selective absorption of the rest-fkS. One form of performance is when a last liquid ring pump is used as a final wash stage with cold, clean water as a cooling and sealing liquid 24. 34 according to figure 25. Another form of performance is a liquid ring pump of type multi wheel, where the number preferably is b^'xnited to one single

fluid 24 are separated by separation device 17 whereupon the gas phase is pressure increased by fan 11 with, gas connection to gas boiler 12. There is a possibility to utilize additional fuel 21. Gas boiler 12, with air addition, is utilized in a conventional way by steam production 89 via boiler feed water 88 or preferably by reheating of internal flows before and/or between the expander stages - for example flow 39. Everything that feeds physical energy to the system has priority. After the gas boiler 12 follows flue gas condensation 22 and fan 13 with flue gas 45 outlet in principle as SCVfree carbon dioxide CO₂, which as an alternative can be recovered. Back to reaction chamber IB the process of which during the reaction progress is -just" above atmospheric pressure, -which makes it possible to by fan- 84 feed air 35B as an oxidizing agent When need for poly sulphide 58 elementary sulphur 69 is added to low sulpbidity white liquor 55 for poly sulphide production:

XS + S²- o S_x ^2-

According to description, figures 11 and 12, there is thus a possibility of direct production of high sulpbidity white liquor 18B, without previous causticishig, meant for the pre treatment/introductory part of the pulp cooking. From the description can also be seen direct production of cooking liquor 56 without preceding causticisiαg, meant for the finish part of the pulp cooking, by mixing AQ-solution 65 and/or 67 with nearly sulphide free green liquor 18A into a mixer 70. The need of the conventional causticising does not occur as the separation need of necessary amount of carbon dioxide (CO₂) is done already during the equilibrium displacement of the reaction progress in reaction chamber IB₅ to the right according to the equilibrium reaction below, with direct production of high sulpbidity white liquor 18B:

Na₂CO₃ + H₂S => Na₂S + H₂O + CO₂

By that remains only a need for causticising of a small part of nearly sulphide free green liquor flow 18A in the main iutended for the bleach plant The proceeding further comprises a possibility to strengthen the sulphur content in reaction chamber IB as black liquor feed 30, 31 - before reaction chamber IB - selectively absorbs part of the combustion gas 38B content of hydrogen sulphide H₂S - which cannot be seen in figure 12.

Figure 13;

The figure comprises recovery of energy and chemicals from a fuel which consists of sulphur rich hydrocarbon compounds during pressurized reaction progress in reaction chamber by understoicbioEictric combustion during high steam partial pressure. The figure describes two

aud ύie other comprises fuel with, content of alkali compounds - or when alkali compounds is added in another way. The later procedure, comprising alkali compounds, has in the figure the correspoDding flow lines broken. In general, chemicals are recovered from hydrogen sulphide H₂S by earlier under figure 10 described AQ-ZAHQ-procedure or another procedure with corresponding function, comprising the recovery of a part or parts of: hydrogen peroxide H₂O₂37, hydrogen H₂ 68 and elementary sulphur S 69, with the possibility to be recycled "within the proceeding and/or to be brought out for other purposes. By the distinctive of the proceeding the outgoing flue gas contains nearly only carbon dioxide CO2 which make it possible to^~beτecovered^~forτeciχculaiion 45A and also to be liquefied -and brought out 45B for other markets or final waste disposal, for example, deep into fuel wells as a working fluid for the fuel. The positions correspond to earlier descriptions among others according to figures 10, 11 and 12 with complementary additions according to this figure for the in- and outgoing fuel gas 42A and 42B respectively of the AQ-/AHQ-proceeding 61-64. Gas boiler 12 produces high pressure steam 89 feeding the steam turbine 120 with counter-pressure steam 89A. Steam turbine equipped with adherent generator 120 for power generation 20. The reaction progress oxidizing agent constitutes of oxygen Oj 36 and with addition of within the procedure produced hydrogen peroxide H₂O2 37. It is also possible to add to the reaction progress internally produced hydrogen H₂ and elementary sulphur S 69, which is a carrier of hydrogen H. When the proceeding is covering alkali, broken lines in the figure, either added by the fuel 30 or as an addition 55, a catalytic effect on the combustion process is obtained, the alkali melt is separated/dissolved after the reaction progress in quench 126 as an alkali solution 18 A, which is cooled through, heat exchanger 118 and thereafter through cooler 119 with necessary pressure decrease before connection to liquid ring pump 9 as combined cooling and sealing water 24/alkali solution ISA for mainly absorption of in the fuel gas remaining hydrogen sulphide H₂S, whereupon the outgoing cooling and sealing water 24/alkali solution 18B, now with sulphur content, via heat exchanger 1 IS connects reaction chamber 1, whereupon the sulphur is desorbed as H2S and thereafter is to be found in the flue gas flow 38. Present proceeding prevents the release to atmosphere of dust particles, volatile organic agents and compounds as well sulphur compounds as carbon dioxide and also rniήirnizes the formation of nitric oxides NOχ. Besides the mentioned, diversified chemical production also recovery of a number of "green" energy forms from fossil fuels/waste is possible, for example petroleum coke 103, in the form of power 20 via turbine connected generators 3, 5, 7 and 121 and as steam 89A as well as, a number of mobile fuels. Figure 14:

The present figure constitutes a modification of the previous figure 13 comprising integration of a pressurized fuel cell procedure, for power generation, with for the reaction progress in the reaction chamber and fuel cell co-ordinated addition of oxygen and with addition of hydrogen H₂ to the fuel cell from earlier, under figure 10 described AQ-/AHQ-proceduχe, or another procedure with the corresponding function. Energy is thus recovered by partial combustion of ^~a

without ^"content ^"of^~sulphurand alkali. When lack,-or insufficient amount, of sulphur and/or alkali this is added to the reaction progress for a partially cyclic process comprising selective absorption and decomposition of the fuel gas content of hydrogen sulphide H₂S by the mentioned AQ-/AHQ-ρrocedure for production of elementary sulphur S₇ hydrogen H₂ and/or H2O₂ whereupon the process comprises absorption of the fuel gas content of ϊ^S-rest and a part of the carbon dioxide COs-content by tbe from melt dissolver of the reaction chamber recycled alkali solution with completion of the cyclic process by desorption of the mentioned H2S and CO2 during the reaction progress in the reaction chamber according to the equilibrium reactions below. Absorption:

Na₂CO₃ + H₂S => NaHCO₃ + NaHS

Na₂CO₅ + CO₂ + H₂O =*^■ 2 NaHCO₃ Desorption:

NaHCO₃ + NaHS => Na₂CO₃ + H₂S

2 NaHCO₃ => Na₂CO₃ + CO₂ + H₂O

The recirculation thus comprises elementary sulphur S as a carrier of hydrogen H in the form of hydrogen sulphide H₂S and by the alkali solution as a carrier of the iuel gas content of rest- H₂S and the amount of carbon dioxide. Besides the high process pressure in the reaction chamber 1 the split of sulphur and alkali is favoured by the high partial pressures of steam as well as carbon dioxide during the reaction progress according to the below equilibrium reaction with displaced equilibrium towards the left:

Na₂CO₃ + H₂S <= Na₂S + H₇O ÷ CO₂

The proceeding according τo figure 14 comprises mainly earlier made positioning, why the figure description obtains a more comprehensive positioning. When fuel 30 has lack of sulphur S 69 and/or alkali 55 these chemicals, according to a refill procedure, is thus added to

chemicals will be in excess, and is recovered from the procedure as elementary sulphur S 69B and alkaline solution 18 C- The chemical recovery comprises according to above also hydrogen 6$ for pressurized fuel cell 122 and hydrogen peroxide H2O₂37, with possible addition 37A to the reaction chamber 1 while possible excess 37B is brought out from the procedure. The fuel gas content of chemical energy is combusted in gas boiler 12 for production of high pressure steam 89 and the operation of steam turbine 120 with adherent generator 121 for power generation 20. The total energy recovery of the proceeding thus comprises power generation 20 by pressurized fuel cell 122 and by generators 3, 5 and 7 connected to expMdeYtϋrbixies amTsteam turbines 120 and 124 after steam-production in gas boiler 12 and after pressurized fuel celj 122 with connected generators 121 and 125 respectively, and when needed tapping off necessary amount of steam 89A and 89B. Flue gas 45, after gas boiler 12 with subsequent flue gas condensation 22, constitutes in principle of only carbon dioxide CO₂, suitable for a liquefied recovery for other markets or long time storing into wells/aquifers as a working fluid for feeding the fuel 30- The expansion of the integrated procedure to negative pressure vacuum, for example 0,05 bar (a), miiumizes the exergy losses with the corresponding maximization of the power generation 20, which means outlet of clean, cold condensate excess within the temperature area of 21 — 25⁰C.

Figure IS:

An interesting integration possibility between the present invention and the pulping process is the proceeding with combustion under partial oxidation according to figure. The integration is in principle valid both for the sulphate as partly also the sulphite pulping processes and comprises the fibre process chip bin 97, chip pre-rreatment 98 and pulp washing 99 together with production of nearly sulphide free white liquor 55 and high sulphidity white liquor 55A. The earlier figure descriptions with corresponding positioning are valid in applicable parts, why figure 15 obtains limited description with application for sulphate pulp production. One of the procedure forms of the reaction process is made by understoicbiometric combustion of sulphate soap 102 as a first step during the reaction progress with ring-shaped, pneumatic dry added sulphate ashes 101 and/or petroleum coke 103 forming a second stage in the reaction progress with pneumatic means of transport preferably consisting of oxygen containing gas and/or steam. After the first expansion stage with condensation out of the fuel gas content of vaporized agents and/or compounds and dust particles (diameter from 0_T0 lμ) the pressurized hot and humid fuel gas 40 with t^S-content, thus with the dust particles removed, is used for

with return of preheated fuel gas 40B to the next expander cooling stage 4. Separated condensate 32 and/or 33A₃ or other flows, are also preheated to maintain the highest possible total physical energy level for optimal power 20 generation. There is a possibility for a conventional flue gas condensation 22 after the gas boiler 12. When during the earlier condensation out of the fine dust particular content of the fuel gas after the reaction progress, the particles are used as condensation nuclei during the condensation process, whereby the particles are wetted/get heavier and transferred from gas phase to the liquid/condensate phase. The cooling and sealing liquid 24 of the liquid ring pump 9 consists of cooled nearly sulphide - jfree"white- liquor 55 or nearly sulphide-free- green-liquor 1-8, the latter -alternative cannot be seen in figure, for against CO₂ selective HjS-absorption by the dynamic shaping of the proceeding with extremely short absorption time of contact, forming the second H₂S- absorption stage- The third and last absorption stage for the remaining H₂S consists of chip bin 97 with operation around atmospheric pressure -just above or below. This stage 97 consists of chip preheating with moisture equalization of the moisture variations of the incoming chips 96. The integration with present liquor evaporation comprises among others the connection of not condensable gases NCG 90 to a common negative pressure/vacuum system 44. Finally,, segregated condensate excess 33, with the content of dissolved carbon dioxide, is utilized for pulp washing 99. The outlet/counter pressure of the gas/condensate mixture 41 of the last expansion cooling stage 4 settles the temperature of the outgoing condensate 33. At for example outlet pressure 0,70 bar (a) a temperature around 63°C is obtained. The described system based on two expansion cooling stages can of course be used for further expansion cooling stages.

The integration of the sulphate pulpins process Figure 16:

The principle for the integration of the pulping process can be seen in this block diagram by the three partial blocks DEUGNIFICATIONPLANTS, PULP WASH 50/87 A/99 and EVAPORATION PLANT 93 and GASIFICATION PLANT, RECOVERY OF CHEMICALS AND ENERGY 150. The delignification comprises as well cooking 50 as bleaching 87A. Wood chips 96 connect block 50/87A/99, the waste liquor of which containing dry substance (DS) 30 with water content 31 connects block 93- From block 50/87A/99 the final product bleached sulphate pulp 53 is produced. Oxygen 36 is fed to this block, forming co-ordinated delivery to block 150 — as an alternative / complement to compressed a5x 35 as oxidizing

between block 93 and block 150. Block 93 delivers black liquor 30/31 and dirty condensate 120 containing almost all of the condensable part within block 93 in around 3-4 volume % of the total condensate flow of the block as among others sulphur compounds >98%, turpentine, methanol and ammonium. This condensate flow 120 can with advantage be preheated within the gas boiler 12 before connection to reaction chamber 1, all within block 150. Further from block 93 non condensable gases (NCG) 90 is fed to one with the block 150 common system for negative pressure/vacuum. Block 150 receives clean condensate 151 from block 93 and brings back the condensate flow 32 of the first expansion cooling stage — the whole or parts of it containing-condensed agents -and/or compounds — as flow 321.- Further -from -block 150 is delivered steam 89 from the gas boiler and outgoing flue gas 45. Block 150 also generates power 20 and recovered chemicals_^ Na- and S- compounds separated, in the form of NaOH 55 and NaHS 55A respectively to block 50/87A/99, and condensate 33, clean and tempered suitable for re-utilizatϊon/pulp washing. Block 150 further delivers one condensate excess 34, clean and cooled, also suitable for re-utilization or out to recipient. Within the block 150 occurring metals/non process elements (NPE) 54 and chlorides are separated from the mill liquor cycle.

Figure 17:

The principle for the integration of a sulphate pulping process can be seen more in detail in this figure, forming one of more possible integrations- The present figure describes an turbine expansion cooled procedure based on segregated condensate recovery by means of four expansion cooling stages with advanced, closed and pressurized chemical recovery comprising the release liquor/black liquor of the digester to the re-charged white liquor to the digester in the form of nearly sulphide free white liquor or low sulphidity white liquor and high sulphidity white liquor. As this figure has been positioned corresponding to earlier figures the proceeding is described in a simplified way mainly comprising newly initiated process stages and apparatus as chips pre-treatment 98, digester 50, "limited" alternatively conventional evaporation 93., DS-increasing process technology as for example membrane separation (87A) for bleach plant effluent 87, pulp washing 99, connected steam/^strong" gas systems including non condensable gases (NCG) 90, separation of metals/non process elements (NPE) 54₇ weak liquor 94 of the caustification plant is fed to the melt dissolver 126, process stage for selective absorption of hydrogen sulphide (H₂S) from the fuel gas by means of counter-currently fed nearly sulphide free white liquor 55 or nearly sulphide fr≥e green

best selectivity of H^S against CO₂, during extremely short contact time between the gas and the liquor for the production of high sulphidity white liquor 55 A or high sulphidity green liquor- The fourth expander stage 6A -with adherent generator 7A for power generation 20, like the previous expander stage, alternatively with mechanical or hydraulic power transmission for engine/machine operation. The cooling and sealing liquid 24 for liquid ring pump 9 consists of cooled condensate excess 34, also used as an extra process stage for gas wash. Segregated condensate flows 32, 33, 33 A and 34A respectively have been marked in the figure with thick lines. The entire chemical recovery as from the outgoing release liquor ^~3O; 3+of the-digester up to-nearly-stuphidefree white liquor-55 and high sulphidity white liquor 55A to the digester 50 comprising a closed high pressure system with pressure level adapted to the process pressure of the digester. Separate process stages within the liquor evaporation 93 are however preferably at lower process pressures. The process pressure of the reaction chamber 1 is preferably higher than the mentioned high pressure system.

The sulphite pulping process, with base of Na

Within pulping industries with production of as well sulphate as sulphite based pulp qualities, the latter comprising bisulphite, NSSC, "cross recovery", CTMP etc. aαd can by present invention use existing, both sulphate and sulphite waste liquors, during common reaction progress for direct conversion to active cooking chemicals in the form of sodium sulphite (Ka^SOs) solution and/or sodium bisulphite (NaHSOs) solution. The fuel of the reaction progress consists besides of cooking/bleaching waste liquors also of sulphate soap, sulphate ashes (Na₂SO-O and petroleum coke with S-content (3-4%) being both S-refill and fuel addition. The combustion takes place during partial oxidation with reaction progress during high process pressure, high steam partial pressure and the lowest possible operation temperature from carbon conversion point of view. By that nearly all sulphur is driven out with the fuel gas in the form of hydrogen sulphide (H2S), The relation of the carbonate solution between produced sodium carbonate (Na₂COs) and sodium bicarbonate (NaHCO₃) is settled in the melt dissolver/quench direct after the reaction process by means of controlled absorption of the carbon dioxide (CO₂) content of the fuel gas according to:

Na₂CO₃ + H₂O + CO₂ <=> 2NaHCO₃ as one single carbonate solution or carbonate and bicarbonate solutions as separate flows. There is also a possibility for separate reaction chambers with respective melt dissolver/quench for separate production of the carbonate solutions. Silicon (Si) from silicon

content of H₂S is combusted is a later process pliase whereby the H2S is oxidized to sulphur dioxide (SO2) and the carbonate solution/s/ absorb/s selectively the SO₂ content of the flue gas for conversion to active sulphite cooking liquid as one solution of Na₂SC>₃ and/or NaHSO₃ ox as separate solutions according to below. This can be preceded by a process stage for absorption of SO₂ in water. The proceeding means among others the possibility to two stage alkali sulphite cooking process with sulphite/bisulphite solution preferably in the first stage - the impregnation stage:

The above is, as can be seen from the equilibrium reactions, a direct conversion process with separation of alkali metals and sulphur compounds. The S0₂-absorption is pH-adjusted suitably by alkali. NaOH, for optimal absorption. The carbonate solution which is free from bicarbonate NaHCOs contains in most cases besides carbonate Na₂CO₃ also a small amount of NaOH which at the SO₂ scrubber stage reacts according to below:

2 NaOH + SO₂ <^ Na₂SO₃ + H₂O

Only a small amount of the carbonate solution which is meant for production of sulphide free or nearly sulphide free aUkali, for example the bleaching process and pH adjustment, needs thus to be_causticised. Gas carried dust particles originating from the reaction progress constitutes condensation nuclei during the condensation, whereby the weight of the wet dust particles are increased whereupon these dust particles are transformed from the gas phase to the liquid/condensate phase, together with earlier vaporized agents and compounds after essential condensation during the first expansion cooling stage, whereupon this condensate flow is fed to a preparing stage for the fuel - for example black liquor evaporation or correspondingly — and/or returned to the reaction chamber together with the added black liquor and fed to the subsequent stage 126 for dissolving/cooling the phase of solid and/or molten material with partial or total moisture saturation of the outgoing fuel gas 38 before and/or after tile solid phase separation. The outlet/counter pressure of the last expander cooling stage constitutes preferably a negative pressure/vacuum for predestined cooling effect with low temperature of the condensate excess. By that the exergi losses of the proceeding are minimized during the corresponding optimization of the power 20 generation or other forms of the energy recovery. According to the present invention the chemical cycle of the mill is

extremely difficult to catch, 2nd according to above transferred to the liquid phase, with final return to the cooking liquor preparation, which, at the same time also obtains the sulphur in return by absorption of the SO₂ content of the flue gas in a later process stage. The above sulphite recovery process is exemplified through next figure 18.

Figure 18:

The fuel to the reaction chamber 1 is fed in the form of either sulphate waste liquor and/or sulphite waste liquor 30 with water content 31 with the addition of bleach plant effluent 87, sulphate ash TOl, sulphate soap 102, sulphur 69 andpetroleurrrcoke 103, as a whole or part of, with combustion during partial oxidation by means of compressed air 35 and/or oxygen 36, and hydrogen peroxide (H₂O₂) 37 as an option. The outgoing pressurized fuel gas 38, of preferably high steam partial pressure contains volatile organic agents and/or compounds and dust particles and H₂S₁, is connected to expansion turbine 2 with adherent generator 3 for power 20 generation and/or mechanical or hydraulic power transmission for operation of engme/machine - for example the air compressor 8. from expansion turbine 2 outgoing fuel gas/condensate mixture 39, now with condensate containing earlier vaporized agents and/or compounds and earlier gas carried dust particles, is connected to separation device 14 with return of this dust and vaporized agents and compounds containing condensate 32 to the preparing fuel stage 321, for example the evaporation plant, -and the reaction chamber 1 and subsequent melt dissolver/cooler 126A and 126B and for partial or total moisture saturation of the fuel gas 38, before and/or after the solid phase separation, in the whole or parts of. The gas phase 40 after separation device 14 is connected to the second expansion cooling stage 4 with adherent generator 5 for power 20 generation or another energy form. From expansion turbine 4 outgoing mixed flow of fuel gas and condensate 41 is connected to device 15 for separation of clean, tempered condensate 33 suitable for district heating, pulp washing etc. Gas phase 42 after separation device 15 is connected to the third expansion cooling stage 6 with adherent generator 7 for power 20 generation or another energy form. This very last expansion cooling stage 6 expands the gas-/condensaie mixture 43, with H₂S content down to negative pressure/vacuum 0,05 bar (a) with corresponding temperature around 23⁰C by the present condensation effect strengthened with some form of negative pressure/vacuum generating equipment, as a whole or part of it, as liquid ring pump 9 after separation device 16, and barometric condensate fall leg with water-seal and vacuum pump 10 on condensate flow 34 to tank 19 with feed out of expansion cooled, clean condensate 34 excess for reuse or to

cooled condensate 34 excess. After separatiori stage 17 for the cooling and sealing water 24 the gas phase 44. with content OfH₂S, is passing fan 11 for feeding the fuel gas to the gas boiler 12 where the fuel gas 44 is combusted during oxidation of the B^S-content to SOo together with the added "strong" gas — non condensable gas (NCG) 90. These gases are also connected to, one for the evaporation plant and the expansion cooling common system for negative pressure/vacuum, at for example gas pipeline 44. The gas boiler 12 is preferably utilized for increasing the physical energy content of the system by preheating the gas and/or condensate phases, before and/or after the expansion stage as for example the gas-/condensate flow 39; alternatively for conventional steam production. After gas boiler 12 the flue gas with SO₂ content is divided in two partial flows with connections to the SC»₂-scrubber 104A and 104B. This can be preceded by a conventional process stage for the absorption of SC^-gas in water. Whereupon the flue gas 45, nowtreated from SCh- is led via gas fan 13 to funnel. There is a possibility to install a flue gas condenser 22 (missing in this figure) after the scrubbers. After the steam condensation of the flue gas there nearly only remains carbon dioxide (CO₂) — besides the nitrogen N₂-content when used compressed air 35 - with a possibility to be recovered and liquefied, for other markets or final waste disposal. Back to reaction vessel 1 , the melt phases 1 SA and 1 SBB respectively of which, pass process stage for melt dissolving and cooling 126A and 126B respectively with liquid addition by condensate 32 to pre decided concentration. Both these process stages 126 A and 126B also settle the relation between the amount of carbonate (NajCθ₃) and bicarbonate (NaHCOs) by the absorption of the flue gas CO^ content The carbonate solutions ISA and 18BB are pressure decreased by liquid expander 8OA and SOB with or without adherent generators 81 A and 8 IB for power 20 generation. The subsequent liquid/gas phases 18 IA and 181B pass the separation device 85A respective 85B with connection of the expansion steam 180 to the earlier described separation device 15. The carbonate solutions 182 A and 182B are after that fed to a mud/pressure filter 95A respective 95B for the removal of NPE 54A and NPE 54B respectively. The carbonate solution 182A also contains a certain amount of NaOH and is divided in two partial flows, when one is fed to the caustification plant 51 for production of nearly sulphide free NaOH 55. The other flow part is fed to scrubber 104A for absorption of the Sθ₂-content of the flue gas and production of sulphite solution (Na₂SO₃) 183 A. The bicarbonate solution 182J3 is fed to SO^-scrubber 104B for the production of bisulphite solution (NaHSOs) J 83B. The proportions of both sulphite flows have thus been pre decided earlier in the process in connection with the melt dissolving 126A and 126B. The figure thus

there- is DO need for separate flows, the proceeding cas be simplified by means of only one gathered flow of carbonate/bicarbonate which later can be transformed to sulphite/bisulphite by only one SCVscrubber stage. Further one proceeding - a quite simplified one - is the production of sulphite Na2SO3 via NazCOj/NaOH-solution 18 from only one melt dissolving stage 126.

The sulphite pulping processes, with base QfMs-, NH±OT Ca

Besides the above described Na-based sulphite process there axe further some sulphite processes witlrother base chentrcals as magnesium (Mg), armnonium (NH₄) and calcium (Ca). Below follows a comprehensive description with figure of respective base according to the present invention. Generally the combustion of these sulphite waste liquors are based on total oxidation during the reaction progress during high process pressure, high steam partial pressure and when occurrence of sulphur the sulphur content is recovered as SO₂ in the flue gas. Base chemical, or the rest of it, is recovered as a phase of solid and/or molten material from the reaction progress and/or in the form of fine particular dust, fly ash, out with the gas phase. The gas carried fly ash is essentially transferred during the first condensation/expansion cooling stage, according to earlier description, to this first condensate flow. The amount of condensate is settled by the process pressure of the gas phase, steam partial pressure and the outlet/counter pressure of the expansion cooling stage. After mis gas cleaning stage mainly concerning the dust content, the SO2-content of the flue gas remains, which principally is absorbed by the actual process base chemical in an ending SO₂ -scrubber stage to actual sulphite cooking chemicals.

Figure 19:

This proceeding comprises the combustion of magnesium based (Mg) waste liquor during total oxidation for the production of magnesium sulphite (MgSO₃) and/or magnesium bisulphite [Mg(HSO^] as sulphite cooking acid. During the reaction progress, temperature

around 900-950⁰C, magnesium oxide (MgO) is formed as fly ash and the sulphur content as SO₂ -with all of it in the gas phase. By controlled stoichiometry during the combustion process almost prevents the formation of magnesium sulphate (MgSO₄) and SO₃. The earlier gas carried MgO-ash passes during the first expansion cooling stage to the hot liquid phase when MgO is transformed by slaking to magnesium hydroxide [Mg(OHb] according to:

MgO + H₂O -Φ=> Mg(OH)₂ In order to secure the reaction folly, normally a certain retention time is required — preferably as here in a pressurized system. Flue gas with among others Sθ2-content passes another expansion cooling stage down to negative pressure/vacuum, preferably within the area 0₃05 — 0.50 bar (a) depending on how the clean condensate excess is utilized. After this the flue gas is fed to a scrubber system, atmospheric or pressurized, for the absorption of the SOi-contenτ during the conditions of the present cooking method according to:

The earlier mentioned negative pressure/vacuum is produced, besides by the condensation effect, among others preferably by the liquid ring pump which cold water supply as cooling and sealing water also comprises gas washing with regard to the content of hydrogen chloride in the gas - thus a form of chloride separation. Sulphite waste liquor with water content, 30/31, is thus connected to reaction chamber 1 together with magnesium sulphate (MgSO₄) or magnetite (MgCOs) as Mg-refill 110 and petroleum coke 103 as S-refiU and fuel addition together with recycled condensate 33 for stoichiometric combustion/total oxidation by means of compressed air 35 as an oxidant with addition of other oxygen containing substances as O₂ 36, H₂O₂ 37 or O₃ -rest 115 (sometimes with traces of CO) from the bleach plant, as a whole or parts of it From the reaction chamber 1 outgoing flue gas 38, superheated or during partial or total moisture saturation, is fed to a first expansion cooling stage 2 interconnected with turbo compressor 8, generator 3 for power generation 20 and with start up motor 83 if generator 3 misses starting up function/reversing. After expansion turbine 2 the outgoing flue gas/condensate flow 39 is fed to separation device 14. The condensate flow 32 with the content of recovered MgO, fully or partly transformed/slaked to Mg(OH)₂ passes a liquid expander stage 80 with or without electric generator 81 whereupon the liquid-/gas mixture is connected to separation device 85 for gathering of MgO-/Mg(OH)₂-liquid phase in tank 1 13 - atmospheric or pressurized. Into this tank MgO 112 is added, if required, as an alternative refill. The outgoing flow of Mg(OH)₂ 114 is fed to a scrubber system 104 for absorption, during pH -control, of the Hue gas SO₂-content. From scrubber 104 the sulphite cooking acid 108 is equipped with the possibility of recirculation 108A. After scrubber 104 the flue gas 45 A is fed via fan 13 to a funnel. Back to the separation device 14 and outgoing flue gas 40 which is connected to the second expansion cooling stage 4 with adherent generator 5 for power 20 generation or another form of energy. After the expander turbine stage 4 the ~_§&s£i€fiad πώf-iar^-^-^βiϊriic^tii"ώ.--'>i_i--ϊ-i-α;r£i-ϊi d^v4c≤4^^r^gώ-_&τ^i1έr<i?a>:-:55-;i3-^ steam -fxsrs^ — separation device 85. After separation device 15 the condensate fraction 33 is fed via vacuum pump 10 with or without barometric condensate fall leg with water-seal to the condensate tank 19 with recirculation of condensate 33 to reaction chamber 1 with the possibility to intermittent condensate flushing 33A when required according to dashed line. The condensate 34 excess from cistern 19 is used for pulp washing 99 or for another purpose — for example district heating 23. The outlet/counter pressure of the last expansion cooling stage 4 settles the temperature, according to earlier described, if re-use is of interest or if the water excess goes to recipient After the separation device 15 the gas fraction 44, containing S 0₂, is fed via

water 24, which also comprises gas washing according to earlier description. After the separation device 17 and fan 11 the gas fraction 45 is led to earlier mentioned SO₂ scrubber 104 whereupon the flue gas 45 leaves the proceeding via fan 13.

Figure 20:

The present figure exemplifies the invention by means of combustion of ammonium sulphite waste liquor [(NFij.)2 SOs] during total oxidation further forming one process variant with the

combustion products almost only gaseous during well controlled stoichiometry, among others in order to avoid acid, adhesive substances. Essentially SO₂ is recovered from/the cooking chemicals but also a small amount of ammomuro/anxmoniac CNH₄ / NH3). The combustion of ammonium/arnmoniac gives nitrogen (N₂) and a big amount of water/steam according to:

2NH₄+ 2O₂ ^> N₂ + 4 H₂O

After the reaction progress the flue gas contains a small amount of fine particular dust originating from the wood raw material as potassium (K), sodium (Na)₃ magnesium (Mg) and sϋicone (Si) which is separated in full or partly direct after the reaction progress or after the expansion cooling stage, preferably after the first expansion stage, which comprises a second separation stage, mainly the most fine particular dust fraction, which thus is recovered in the condensate according to earlier description. Further fine particular dust originating from the reaction progress constitutes of ammonium salts which in the corresponding way is recovered in the condensate. The equilibrium of the alkaline content is strongly influenced by the process pressure during the reaction progress according to:

NH₄ ⁺ c=> NH₃ + H^~ An increased reaction pressure thus displaces the equilibrium towards the left. A more

condensate phase after Λe first expansion cooling stage, containing as well NHd as NHj, is brought back partly to the reaction progress and partly to the absorption stage for utilization of the SOa-coαteπt of the flue gas by generation of renewed ammonium sulphite solution

[(NH02 SO₃]. As not all the ammonium is recovered, refill is required in the form of fresh

ammoniac (NH₃) to the absorption stage. The system for the recovery of the -whole ammonium sulphite solution can as an advantage be performed pressurized. The chloride separation of the system is done by washing out the hydrogen chlorine content of the gas phase by "cold watei-or cooling and sealing water 24 for the liquid ring pump 9. The ammonium sulphite waste liquor 30. according to above, with water content 31 is thus connected to reaction chamber 1 together with external condensate containing aJDαmoniurn/arnmoniac 120, recycled condensate 32A and petroleum coke 103, being S-refiH and fuel addition (option), in full or parts of it, for stoichiometric combustion/total oxidation by compressed air 35 as oxidizing agent Dust particles originating from the reaction progress and the wood raw material are separated together with a small amount of slag etc through a small separation flow ISA and when required also 18B. From the reaction chamber 1 outgoing flue gas 38- superheated or during partial or total moisture saturation, with the content of as well SO₂ as someNHs is fed to a first expansion turbine cooling stage 2 connected to turbo compressor 8 and generator 3 for power 20 generation and start up motor 83. After expansion turbine 2 the outgoing flue gas/condensate flow 39 is fed to separation device 14. The condensate fraction 32 A and 32B, now containing the earlier gas carried fine particular dust, is brought back to reaction chamber 1 by condensate 32A and with a small flow to separation/cooling equipment for slag, melt etc 18 A, while the fraction 32B is fed to SOz-scrubber 104. The later process stage can be carried out pressurized or nearly atmospheric according to figure. The condensate flow 32B is pressure reduced according to requirements through pressure reducing valve, alternatively through a liquid expander stage (not shown in figure). Fresh ammoniac (NH₃) 121 being a refill is added to the scrubber system 104 for SCb-absorption and further production of ammonium sulphite cooking acid 108 with recirculation flow 108 A according to requirements. Back to separation device 14 and separated flue gas 40, with content of SO? and a small amount of NH₃, the flue gas is connected to nerct expansion turbine cooling stage 4 with adherent generator 5 for power 20 generation or another form of energy. According to earlier process descriptions/figures, the outlet/counter pressure after the last expansion cooling stage settles the final temperature of

Moreover in this figure the same arrangement is shown with liquid ring pump 9 and vacuum pump 10 etc corresponding to earlier figure descriptions.

Figure 21:

The proceeding according to the present figure comprises as a principle the original, now closed down sulphite pulping process, based on calcium (Ca). This proceeding is the last exemplification of the sulphite pulping process within the present invention. The combustion ^""of tEe sulpnlte w-aste liquor is^so^"fere^^e^"^uring^~totaJ^"Oxidatron and "undersell controlled stoichiomerry and reaction temperature with only gas bounded recovered chemicals as a consequence. Quite decisive is that the calcium base is recovered in the form of calcium oxide (CaO) which requires a temperature above 1150-120O⁰C during the reaction progress, while the sulphur is recovered as sulphur dioxide (SO₂)- The fine particular calcium oxide dust

(CaO) is transformed by slaking to calcium hydroxide [Ca(OH)₂] , in one or more stages, the

one in a pressurized quench direct after the reaction progress and the other stage in a later process stage. Commonly for both stages is that the CaO-dust is slaked with water according to:

CaO + H₂O <=> Ca(OH)₂

Whereupon the calcium hydroxide [Ca(OH)₂] is carbonized by the flue gas carbon dioxide

content (CO₂) to calcium bicarbonate [Ca(HCOs)₂] according to:

Ca(OH)₂ + CO₂ c^ Ca(HCOi)₂

The carbonizing continues in parallel with the slaking as a first stage in quench 126A direct after the reaction chamber with the second stage — atmospheric or pressurized - as a multi functional apparatus 126B (figure 22) after the first expansion cooling stage with tie following extent:

• Separation, gas/condensate flows

• Addition/refill of fresh "substance^"', for example CaO or Ca(OH)₂

• Carbonizing Whereupon the calcium bicarbonate flow is fed to absorption tower/scrubber for absorption of the fhie gas SCh-content for the production of calcium bisulphite [Ca(HSO₃^] as cooking

acid liquid according to:

Ca(HCOs)₂ + 2SO₂ ^ Ca(HSOs)₂ + 2CO₂

Calcium is only dissolvable in bisulphite form and below pH 2,3. Calcium sulphite waste liquor 30 according to above with water content 31 is thus connected to reaction chamber 1 together with S-refill 103 in the form of petroleum coke (3-4% S) and/or as sulphur S. and/or calcium sulphate CaSO₄ and recovered condensate 33. From reaction chamber 1 outgoing flue gas 38 with content of CaO-dust and SOa, superheated or during partial or total moisture saturation, is connected to a first expansion cooling stage 2 connected to turbo compressor 8 and generator 3 for power 20 generation or another energy form. After expander 2 the outgoing flue gas / condensate mixture 39 with the content of CaOZCa(HCOa)₂ is fed to separation device 126B with further functions as slaking and carbonizing. The calcium bicarbonate solution 127 prepared by the multifunction stage 126B is fed to scrubber 104 for the absorption of the flue gas Sθ₂-content and the production of calcium bisulphite solution 108 with possibility to recirculation 108 A. Whereupon the flue gas 45 is fed via fan 13 to funnel. According to earlier figure descriptions the outlet/counter pressure of the last cooling, turbine expansion stage settles the temperature of the gas/condensate fluid. When needed a greater negative pressure/vacuum, besides the condensation effect among others created by liquid ring pump 9, there is a possibility of liquid ring pump operation by connection with, for example, the last expander turbine stage in the corresponding way as the turbo compressor 8 at the first expander turbine stage 2,

Figure 22:

The present invention thus also comprises a multi functional apparatus 126A/126B according to this figure with a number of different process possibilities according to the conceptual circumstances:

• Separation of gas-/liquid-phases

• Gas moistening before and/or after the smelt separation Smelt dissol ver/quench

• Carbonizing of "'substance" in for example hydroxide form by the gas CO_z-co;πtent • When appropriate avoiding the carbonizing effect

• Refill of fresh "substance" in for example carbonate, oxide or hydroxide form

• Addition 4ON of ammoniac NH₃ and/or urea (NBV)₂CO in order to chemically reshape nitrogen oxide NO_x to nitrogen N₂ and steam

The site of the multi functional apparatus of the proceeding is either direct after the chamber reaction progress and/or direct after the discharge of the first expander cooling turbine. The apparatus, preferably pressurized, consists of a system of concentrically designed intermediate walls 125 creating a form of multi stage liquid-lock for the best stirring with the best contact between gas phase 40 and the liquid phase 127 with the possibility to supply "substance" as 18, 112 as well as 4ON direct into the stirring zone. The bottom part of the intermediate walls 125 are carried out with saw-toothed design 125 B fortia^tiest flow distribution all around the turns.

The integration of the sulphite vulvitis process

The sulphite pulping process with its different ""bases" has earlier been described according to sections and figures 18-22. By the present invention, the possibility of direct conversion of among others Na-based cooking chemicals is thus presented - consequently without the e?cten≤ive and expensive separan^'ori/sp-it of alkali metals and sulphur compounds. The ultimate eDergy and chemical recovery occurs at integration of these sulphite pulping processes. Below follow figures 23 and 24 showing direct production of sodium sulphite (Na₂SO₃) and/or sodium bisulphite (NaTISθ₃) — all according to the process requirements.

Figure 23:

Separate process details have earlier been described under The sulphite pulping process with base of Na and by Figure 18, why this figure gives a more overall description. Sulphite waste liquor 30/31 thus connects evaporation plant 93 together with flow 321 constituting all or parts of the condensate flow 32 from the first expansion cooling stage with content of condensed agents/substances and compounds. From the evaporation plant 93 leaving flows consist of besides thickened spent liquor 30/31 also of a small condensate flow 120 containing a large part of the occurring condensed volatile agents/substances and compounds which together connect the reaction chamber 1. The vacuum system of the evaporation plant for non condensable gases NCG 90 is co-ordinated with the corresponding system of the expansion

progress of the reactiorj chamber 1 is characterized by distributing sulphur (S) with the ftiel gas as H₂S and sodium (Na) with the melt fraction as a solution of NaOH and Na₂CC>₃, alternatively as OuIyNa₂COs and/or NaHCθ3 by means of piping 182. These Na-compounds absorb by the gas boiler 12 oxidized H2S to SO₂ by a subsequent SO₂ absorption stage 104 when the Cθ2-amount leaves the carbonate compounds via the flue gas 45. This is preferably preceded by a conventional process stage for absorption Of SO₂ La water. The sulphite solution 183 in the form of Na2$θ3 and/or NaHSOj has by that get ready. Segregated condensate recovery is obtained by means of hot and contaminated condensate 32, which is returned, -tempered^ clean and Cθ2-containing-condensate -33 -is -suitable for example pulp washing and the expansion cooled, clean condensate excess 34 for any kind of re-use or to recipient This condensate recovery/segregation— without any cooling water need — is a strong contribution to the present, efficient and closed, recovery process. Steam 89, preferably as high pressure, is produced by means of feed water 88 via gas boiler 12. Power generation 20 by a triple stage turbine expansion cooling procedure, expanders with adherent generators 2/3, 4/5 and 6/7 respectively, alternatively by expander turbine operation of another engine as compressor 8.

Figure 24;

Within the present figure a number of separate process details have been described earlier, mainly under section above, figure 23. What is made clear by the present figure 24 is the extensive integration by the S-/Na-split of the reaction progress 1, the segregated condensate recovery and the flow exchanges with the evaporation plant 93 comprising the NCG-system 9O₇ gas boiler 12 with preheating of dirty, segregated evaporation condensate 120 before connection to the reaction chamber 1 and the production of steam 89 for among others the evaporation plant 93. Clean condensate 151 from the evaporation plant is connected to the corresponding condensate flow from the turbine expansion cooling stage 4. After gas boiler 12 follows an Sθ₂-absorption stage 104 by alkali solution 182 constitutes a nearly sulphide free green liquor NaOH + NazCθ₃- This is preferably preceded by a conventional process stage for absorption of SO₂ in water (can not be find in the figure). After the Sθ2-absorption stage — comprising the necessary separation of the carbonate Cθ₂-content — the completed sulphite solution Na₂SO^ 183 is obtained. The integration also comprises causticising 51 of a partial flow of nearly sulphide free green liquor 182 for the production of nearly sulphide free NaOH 55 mainly for bleaching plant 87A, the effluent 87 of which is connected to evaporation plant 93- Below there are some sections, which deal with essential — generally valid -process conditions within the present invention:

The steam partial pressure

The energy parts of the gas phase consist of:

• The chemical energy

The part of chemical energy comprises the fuel value of the gas, mainly from the gas parts of CO₃ H₂, CH₄ and H₂S, expressed as efficient heat value kJ/Nm³ dry gas.

• The physical energy

The part of physical energy comprises gas pressure, temperature (sensible heat), evaporation/conderisation (latent heat) and when there is a melt also with addition of chemical (dissolving heat) and physical heat

The energy parts above are distributed by the operation criteria of the reaction progress — essentially by the steam, partial pressure. Increased steam partial pressure gives the I corresponding increased part of physical energy into the gas phase at the cost of the part of chemical energy. The steam partial pressure influences also the reaction progress in full, from the very first start of the progress to its ending phase. The latter comprises the very important and sensitive end oxidation of the remaining char/heavy hydrocarbon compounds, the steam reforming of which is in direct proportion to the steam partial pressure. The high steam partial pressure can also make possible an interesting energy contribution to the reaction progress in the form of natural gas/methane (CH₄) as for example atomization agent with eπdothermic equilibrium reaction according to: CH₄ + H₂O + W 0 CO + H₂

The equilibrium is displaced towards the right by the (water) steam. The principle also allows production of synthesis gas (CO + H₂) out of natural gas as a raw material during simultaneous gas cleaning and energy recovering in the form of power generation alternatively mechanic or hydraulic operation of engine. Increased steam partial pressure increases naturally the steam amount/volume. Necessary apparatus volume is however more than enough compensated for by the preferably increased process pressure. The chloride separation

When there are chlorides into the fuel in connection with energy and chemical recovery and especially wiαen closing a system/cycle, it is a condition that the chlorides continuously are separated out of the system in order to prevent chlorides building-up. There is a possibility, when combustion, preferably during total oxidation, of a fuel with content of sulphur compound and chlorides (NaCl/KCl) to transform these chlorides to hydrogen chloride (HCl), when sulphur dioxide (SO₂) present, which facilitates the transformation, whereupon -chlorides axe separated in the-fornrof HQ-via hydrochloric acid-scrubbers or-correspondingly. These circumstances are essentially applicable within some of the sulphite pulping processes - for example when utilizing the chloride rich fly ash (Na₂SO₄) of the sulphate mill - with, the chemical recovery of among others sulphur in oxidized form as sulphur dioxide (SO₂), whereupon the chloride separation takes place in the form of hydrogen chloride, which is dissolved in the following cold water scrubber, liquid ring pump 9 or correspondingly to hydrochloric acid (HCl).

The carbon conversion

The principal control function of the oxidation progress is most often the remaining part of char and/or hydrocarbon compounds. Partial oxidation — thus gasification — means increased difficulty to achieve necessary, nearly one hundred percent carbon conversion. Increased steam partial pressure is quite decisive for the possibility to achieve the requirement of the carbon conversion degree. Steam gasification or steam reforming reduces the partial pressure of the hydrocarbon compounds when processes that lead to carbon/char formation are counteracted. Steam gasification of char is for example 3-4 times faster than the corresponding oxidation potential of carbon dioxide (CO₂). The strong importance of the steam can be seen in the equilibrium reactions below. Increased steam partial pressure (H₂O) displaces the equilibrium towards the right, and the potential driving force increases in proportion to the increased steam partial pressure. The operating conditions make possible as an almost pure water gas reaction:

■ The maximum carbon conversion: 3C + 2H₂O ^ 2CO + CH₄

^■ The summation reaction of the carbon conversion: 2C ÷H₂0 + O₂ O CO + CO₂ + H₂

LSFirn

«• ^' CO -÷ -π) H£^~ ■ ^"Hie steam reforming:

■ The water gas reaction:

^■ The water gas equilibrium:

Regarding the waste liquors of the pulping industry and for example the black liquor of the sulphate pulping process the content of sodium and -sulphur compounds forms-εrphase of solid and/or molten material at temperatures above the area 760 — 800⁰C. When a chosen temperature margin of around 100⁰C above said temperature area, an almost optimal reaction process can be made according to the present proceeding during almost complete carbon conversion - thus above 99,5% - thanks to the favourable steam partial pressure with the said unproved end char oxidation. Ih this way the temperature level of the reaction progress can be restrained to the area of 880 - 92O⁰C.

The equilibrium reactions ofifie reaction progress regarding alkali/sulphur split

The pulping industry has since a great number of years an unsatisfied requirement from the research and development side, when recovering chemicals and energy from the waste liquors, regarding the need for spEt of alkali and sulphur compounds as separate flows. The split should be almost total. It has thus surprisingly turned out that, according to the present invention, a certain combination of process criteria during the reaction progress - according to below— makes total optimization possible of as well the fibre process as the chemical and energy recovery in the form of among others high degree of sulphate reduction, high degree of Na-/S-split and lower total steam consumption and almost without any need for cooling water with subsequent considerably higher efficiency of power generation, or another energy form, thanks to essentially lower exergi losses. The principal equilibrium reaction for the alkali/sulphur separation— the split - constitutes by: Na₂CO₃ + H₂S & Na₂S + H₂O + CO₂

The equilibrium displacement towards the left is almost total by the below process criteria during the reaction progress — thus the sulphur is driven out with the gas phase in the form of hydrogen sulphide (H2S), when a carbonate melt (Na₂COg) remains almost completely free ^'Soin^'sui'p2iQe^" _V-N S₂S)^" iiie

socπum hydroxide (NaOH)- • High, process pressure

• High, steam partial pressure

• The lowest possible temperature during the reaction progress, iϊorα the carbon conversion point of view. Char is oxidized, besides by oxygen and steam, also by carbon dioxide (CO2) which in this respect is in opposition to hydrogen (H₂) and carbon monoxide (CO).

• Recycling of carbon dioxide to the reaction progress.

• HfgEer bxygenVfoel fario gϊves^'bigger amoϋnToϊcafHon 3ϊόχϊcLe^~at the^~cost of the amount of oxidation restraining hydrogen and carbon monoxide.

• The energy recovery of the expansion cooling turbine is favoured by the great part of physical energy in the gas phase, essentially in the form of pressure, temperature and condensation heat — the latter as a result of the high steam partial pressure.

It can be noted that at causticisiπg of nearly sulphide free green liquor, the white liquor preparation is influenced positively by the feet that the causticisrng degree wiU be higher, when the ion strength relation is changed positively. Table below shows the distribution of Na-/S-comρounds — so called split— at different operation criteria during the reaction progress as steam partial pressure (Gas vol. -VoHjO) and temperatures (⁰C) and pressure conditions (bar a). The content of Na-/S-compounds of the melt (Melt weight- %) can be seen together with a summary of the S-content of the melt (Sum. S weight- %). The amount of physical energy of the outgoing gas phase can also be seen (Phys. in gas out %). As a reference f'Ref. 33 "J the operation criteria of the combi concept/integrated combined cycle concept (IGCC) have been chosen with DS-content 75%, operation pressure 33 bar (a), operation temperature 95O⁰C which gives the amount of S in the melt phase as Na₂& being 11,57 weight-%.The possibility to split at the present invention can be seen in this table with the amount of S in the melt phase, as Na₂S, of only 0,57 - 0,90 weight- % within the temperature and pressure area of the reaction process 880-920⁰C and 150-200 bar (a) respectively. According to reference ("Ref 33") the gasification criteria of the combi concept, and experiences done, the low temperature area of 880-920^DC is quite impossible in order to among others achieve a necessary carbon conversion degree.

Table below with the Na-/S-spIit at different operation conditions during the reaction progress: • Tbe reference CRef. 33"):

Black liquor of DS-content 75% ^"without any content of sulphate soap, operation pressure 33 bar (a), temperature 950⁰C, oxidizing agent of 90 % O₂.

• The present invention:

Black liquor of DS-content 40% with remaining sulphate soap, oxidizing agent of 90 % O₂.

Different operation criteria according to table below: - — Reactiontemperatuτe^~820=i G00°e— - Reaction pressure 100-200 bar (a)

The oxidizing agents

The present invention does not ailow only oxygen containing gas as an oxidizing agent but also "oxygen containing liquid" — for example hydrogen peroxide solution (H₂O₂)- Hydrogen peroxide has a large thermodynamic energy content, which means that large amounts of energy are released at its decomposition during the reaction progress and give besides oxygen also valuable steam as rest products according to the decomposition reaction below, which further increases the steam partial pressure and by that also the valuable part of physical energy into the gas phase. - - 2H₂O₂ <r> O₂ + 2H₂O

The decomposition reaction, according to above, occurs rapidly and is exothermal. It is catalysed by the contact of the progress with alkali compounds, organic substance, heavy metals and high temperature. Besides that the decomposition reaction is favoured by the extraordinary big contact surface by tihe atorπization of the fuel into small droplets, preferably within sizes 50μ - 0,50 mm- The concentration of the hydrogen peroxide solution - usually 30-90 % content OfH₂O₂ — influences the intensity of the reaction progress as well as the steam partial pressure. The production of hydrogen peroxide on-site of fuel gas from gasification of pulp waste liquors, to be utilized as a bleaching agent for pulp products, is earlier known from patent document SE 93 / 00778. Through the process design described by the present invention it is also possible to produce hydrogen peroxide on-site firom hydrogen sulphide H₂S and to utilize the hydrogen peroxide as an oxidizing agent during the reaction progress. An interesting utilization of the decomposition reaction of the peroxide during the reaction progress is, in full or partly, to achieve necessary operation pressure during the reaction progress by the hydrogen peroxide addition- Further one reactive, possible oxidizing agent is ozone (O₃).

The fuels/raw materials

Suitable fuels and raw materials within the present invention are exemplified according to below:

• Petroleum-rests-/-fracti.ons/-coke_;( crude oil, heavy sulphur rich oil, heavy oil, waste oil, diesel oil, paraffin.

• Coal, coke, bitumen

- Hydrogen (H₂), mercaptaπ, NCG, hydrogen compounds as for example hydrogen ~^{^^}plϊ6^~:^Se^h-3Of;tiϊ^^ • Refill: sulphur (S)₅ hydrogen sulphide (H₂S)- green liquor raud, sulphate soap, tall oil, sodium sulphate/fly 3ShNa₂SO₄

• Alcohols, ether compounds (as DME), turpentine, esters

• Household refuses, slaughter house refines/animal rest products, cremation

• Bio fuels/renewable fuels:

* Waste liquors within the pulping industry:

Sulphate pulp, Sulphite pulp, NSSC, "Cross recovery" ^~ — ^"Cbemi-/m"echaiiical pulp, CTMP

* Salix, micro algae, bark, logging waste, saw mill rests

* Bio mud, digested sludge (also containing CH^-rest), molasses, olive seeds, vegetable oils and grease, biogas

* Peat, one-year plants/field crops including seeds/straw fuels

The energy distribution

The proceeding according to the present invention is mainly based on the evaporation during the reaction progress essentially of water, during considerable energy absorption in the reaction chamber with subsequent steam condensation, during corresponding energy emitting at expansion cooling in at least one stage during at least one partial stage of some type of expansion cooling turbines, with both, progresses acting direct without any effectiveness/efficiency restrictive influences of heat exchanger surfaces, and in, principle quite without any cooling water consumption. The total Isentropic efficiency of the proceeding is also very high by the recirculation of high temperature condensate/s and above all at multistage expansion cooling. La this way the amount of exergy losses is minimized substantially, with for example when given, priority to power generation, at very high α-value — thus the ratio between produced power and the heaL The energy distribution between power generated and produced heat is governed by the total/overall recovery need and by that the process elaboration as combustion under partial and/or total oxidation as well as the number of stages during the reaction progress, and further the number of expansion cooling stages/partial stages with chosen outlet/counter pressure and by that also the outlet temperature and the distribution of respective amount of condensates — a segregated condensate recovery.

level of the final fraction of the condensate — thus a cooled and clean water for rε-utilizaticn or to be fed to the recipient. At the later case it is suitable with expansion cooling down to temperature around 2O⁰C. A further carrying out is a condensate integratioD with some type of heat pump arrangement, when especially the last condensate fraction is utilized for the mentioned arrangement with for example expander turbine operation of the heat pump compressor.

The energy distribution with for example combustion during total oxidation of essentially dry ^"delivered fuel with turbo compressed air as an oxidizing agent and recirculation of the condensate flow/s between the evaporation and condensation sequences, the energy distribution when given priority to power generation is calculated to:

• Power/electricity production 70-72 %

• Losses o Electricity consumption (not recovered energy) 6 % o Various heat losses 14 % o Unbalance in the amount of recycled condensate - thus excess/deficiency 8-10 %

WheD combustion during total and/or partial oxidation of wet delivered fuel with turbo compressed air as an oxidizing agent a somewhat larger unbalance arises with the corresponding excess in the condensate handling and according to that somewhat higher exergy losses as a consequence, mainly depending on the amount of water in the fuel, type of oxidation progress and the conditions for the condensate re-utilization. The calculated energy distribution when given priority to power generation is:

• Power/electricity production 68-70 %

• Losses o Electricity consumption (not recovered energy) 6 % o Various heat losses 14 % o Unbalance/excess in the amount of produced condensate in relation to the recycled amount 10-12 % Comments to the extent

• By the raw material of the pulping industry, comprising wood chips, among others potassium (K). sodium (Na) and sulphur (S) are added to the chemical cycle.

■ When alkali metals or sodium compounds are described, it must also be understood that potassium compounds vvill come naturally according to above.

• The invention also comprises so called "sulphur free" pulping processes, including the soda process — however with the exception that sulphur is not added in another way than above.

• 7^"he invention is also applicable on so called "causticising free⁷⁷ recovery processes as for example at utilizing of titanate, treatment of sulphide free green liquor with ferrite or boron addition which reduces the Deed of caustLcising.

• Regarding the expander turbine or the corresponding arrangement of the expansion ^• cooling stage, it must be understood that the added gas is moisture saturated or partially moisture saturated — the latter corresponding to somewhat super heated.

• It must be understood that the name combustion/thermal decomposition comprises as well total oxidation as partial oxidation. The latter is understoichiometric combustion — thus synonymous with gasification.

• It must be understood that during certain circumstances the oxidation progress will occur without any real flame.

• It must be understood that in certain parts similar wording in earlier known, published documents regarding understoichiometric combustion — a reducing process — differs essentially from an apparently similar wording in the present invention which in certain parts describes stoichiometric combustion — an oxidizing process.

Claims

PATENT CLAIMS

1. Method for recovering energy and when appropriate also chemicals, the recovery of said chemicals comprising part or parts of: phase of solid and/or molten material, sub- /microscopic and visual dust particles, in gaseous state or in aqueous form, from a fuel comprising a part or parts of: hydrogen, hydrocarbons and hydrogen compounds, by combustion/thermal decomposition duiirjg partial and/or total oxidation, thus πϊ-βeτ^oicJbiomeTπc^"an37OT^fo^"ιciϊL01ne^:tric όf^"όverstoichiδmetric combustion, in at least one reaction chamber during at least one reaction progress within a pressure interval of 2 - 220 bar (a) and a temperature interval of 600 - 3100^αC, whereupon produced gas, superheated or during partial or total moisture saturation, with content of chemical and/or physical energy is cooled by condensation of into said gas vaporized agents and/or compounds, c h ar a c h t e r i z e d i n that the condensation takes place by expansion cooling through at least one expansion turbine (2, 4, 6) during at least one partial step or by similar apparatus with corresponding functioning, when from the oxidation progress of reaction the chamber (1) originating gas carried sub-/microscopic and visual dust particles, comprising fumes, are wetted during the condensation, when said dust particles constitute condensation nuclei for the vaporized, condensable agents and/or compounds, whereby the weight of said dust particles is increased and said dust particles fall out of the gas phase (38) with transfer into the liquid/condensate phase, which phases are separated by at least one separation device (14, 15, 16) simultaneously when the gas phase contains chemical energy, said energy is utilized for production of chemicals and/or energy (20, 89), while the gas content of physical energy during the expansion cooling is converted into (electric) power (20) by at least one expander turbine connected power generator (3, 5., 7) and/or converted by at least one expander turbine for driving at least one stationary machine (8, 82) or for driving a mobile machine/engine (83A)₅ while further chemicals are recovered as at least one phase of preferably solid and/or molten material and/or as said dust particles and/or in gaseous state and/or in aqueous form, when preferably said solid phase is separated by at least one quench (18) to be resolved, when appropriate, into at least one water containing medium (32, 94) by said quench and/or by at least one melt dissolver (126) as at least one aqueous product, while said dust particles mainly are transferred into the liquid phase by the condensation progress during the expansion cooling, while the gas flow containing gaseous components, suitable for recovering, said

^'compbne^ts^'ifeTecbvereα.^'by at ieasTonelJtep^~af gas^'tfc^'airήeήt device ^'(61-64^", ^i -92) lor ^"the^" production of apart or parts of : phase of solid and/or molten material (58, 69), gas phase (6&, 45A-45B) and liquid phase (37, 55 A, 108- 183) with return of within the method recovered chemicals, as a whole or parts thereof, and/or to be brought out of the method.

2. Method according to Claim 1, c h ar a c t eri z e d in that the condensation comprises water/steam and when appropriate also other condensable agents and/or compounds as volatiJizable chemicals, volatϋizable organic agents and/or compounds and volatϋizable none process elements (NPE)/heavy metals and/or metals.

3. Method according to any of Claims 1 - 2, c h ar a c t e r i z e d in that the steam partial pressure of the reaction progress into the reaction chamber (1) is at least equivalent to through oxidizing agent, atomizarion agent and/ov fuel (30) oxidation equivalence of provided amount of hydrogen, and/or the steam partial pressure is increased equal to the reaction progress supplied amount of water containing agents comprising said fuel included amount of water (31) and/or to said fuel added amount of water and/or direct to the reaction progress added amount of water and/or steam, said added water comprising preferably from the expansion cooling returned condensate and more preferably from a first expansion turbine step (2) returned condensate (32), as a whole or a part thereof, containing earlier gas carried sub-/microscopic and visual dust particles comprising fumes and/or earlier evaporated agents and/or compounds.

4. Method according to any of the preceding claims, c h ar a c t e r i z e d i n that condensate returned from the expansion cooling progress is connected to at least one previous process step for pre treatment (321) of the fuel (31) before the reaction chamber (1) and/or when appropriate connection of said condensate to at least one quench (18) after the reaction progress and/or at least one process step for after-treatment (126) for recovering at least one phase of solid and/or molten material in preferably aqueous form and/or with the connection of said condensate to at least one gas phase (38) for partial or total moisture saturation of said gas phase before and/or after separation of said phase of solid and/or molten material.

5. Method according to any of the preceding claims, c h ar a c t e r i z e d i n that the operation pressure after the reaction progress is gradually reduced by the expansion cooling progress, resulting in segregated recovery of condensates by multi stage expansion cooling with respect to cleanness, flow amount, pressure and temperature of said condensates, depending on dϊscharge-/counter pressure of respective expansion cooling step, down, to suitable level of said pressure according to further requirements of the recovery, when final step of the expansion cooling preferably takes place ^■ downto-aboirt atmospheric pressure, more preferably down, to negative pressure/vacuum and most preferably extended down to the interval of 0,02 - 0,20 bar (a), when the gas/condensate flow after completed expansion cooling, at for example the discharge-/counter pressure of 0,03 bar (a) corresponds to a temperature of 18 - 20⁰C equivalent to extended energy recovering by the expansion cooling turbine, with/or without a following integration of any kind of heat pump proceeding depending on existing requirements of the recovery.

6. Method according to any of the preceding claims, c h a r a c t e r i z e d i n that fuel atomization agents of the burner system of the reaction chamber consist of hydrogen and/or gaseous hydrogen compounds and/or hydrocarbon compounds or oxygen containing gas or combinations hereof, preferably during partial or total moisture saturation of said atomrzation agents by water containing agents, more preferably steam and/or hydrogen peroxide H2O₂-

7 Method according to any of the preceding claims, c h a r a c t e r i z e d i n that oxidation agents of the reaction progress consist of oxygen containing gas and/or oxygen containing liquid, the oxygen containing liquid preferably represented by a solution of hydrogen peroxide H₂O2, preferably by simultaneously pressurizing said reaction progress of the reaction chamber by decomposition reactions of said solution of hydrogen peroxide, as a whole or part thereof.

8 Method according to any of preceding claims, c h a r a c t e r i z e d i n that equilibrium and decomposition reactions of the reaction progress, with or without any additives as activators/catalytic agents, takes place during total oxidation of the fuel, preferably by pressurizing said reaction progress by reactions

free from carbon C and hydrocarbon compounds, said additives comprising a part or parts of turbo compressed air and/or oxygen O₂, hydrogen peroxide H₂O_2? hydrogen H2 and ozone O₃, with an alternative possibility to initiate a certain amount of said ozone direct into said air/oxygen flow by any kind of known method as for instance supplying electrical energy and/or ultraviolet light/radiation into said air/oxygen flow, with further possibility to integrate a fuel cell process (122), preferably pressurized, whereby after completed expansion cooling by expander turbine and preferably for driving of any kind of mobile machine (83A)₅ comprising railway, vehicle, shipping, submarine and aircraft, discharge of rest product only consists of -clean condensate —when using-compressed air said discharge also comprises inert nitrogen N₂-

9. Method according to any of the preceding claims, c h ar a c t e ri z e d i n that after completed expansion cooling the gas phase consists of nearly only carbon dioxide COT, when appropriate for recovering in form of a part of said carbon dioxide (45A) to be recycled into the reaction progress constituting a part of the oxidation agents, as an outer cycle, while the rest part of said carbon dioxide (45B) is brought out and preferably liquefied for external market or for final waste disposal deep into underground of fuel sources/aquifers and where appropriate as a working fluid for feeding the fuel (30), and when appropriate still one more recycled part of said carbon dioxide is possible, representing an inner cycle, through the addition of alkaline earth metal into the recycled condensate (32) in order to essentially absorb said carbon, dioxide from the gas phase, whereupon the content of said carbon dioxide into said condensate is desorbed/released durJDg the reaction progress into the reaction chamber (1), which said alkaline earth metal can after the reaction progress be recovered as a phase of soluble solid and/or molten material (18) preferably utilized for another of said inner cycle.

10. Method according to any of preceding claims, c h ar a c t e r i z e d i n that when presence of alkaline and/or sulphur agents and/or compounds into the fuel, and/or after addition to the fuel of said agents aud/or compounds, the process criteria of the reaction progress are preferably as partial oxidation of the Jftiel during high process pressure, preferably 30 - 220 bar (a), more preferably 50 - 150 bar (a), with high steam partial pressure, preferably 20 - 150 bar (a), more preferably 35 - 110 bar (a), and from carbon conversion point of view lowest possible reaction temperature, preferably 820 -

the reaction progress by recycling carbon dioxide CU₂, for split of alkaline compounds essentially as a phase of solid and/or molten material as well as of suWmicroscopic and visual dust particles (comprising fumes) into the gas phase, with the sulphur compounds essentially as a part of the gas phase.

11. Method according to any of preceding claims. c h a r a c t e r i z e d i n that when partial oxidation of a sulphur containing fuel (30) the produced fuel gas contains hydrogen sulphide EføS. said hydrogen sulfide or a part thereof, is - selectively-recovered by at least onerpreferably pressurized^ Purisol- or-Arnin-process for a selective and regenerative absorption of the EfeS-content, or by a corresponding method, with a following step of reversible thermal decomposition of hydrogen sulphide H₂S- preferably pressurized and preferably counter current to recovered sulphur melt S versus said flow of hydrogen sulphide, at a temperature over 300⁰C, to elementary sulphur S and/or poly-sulphide S_x ^2~and hydrogen Hi, alternatively by selective recovery of said hydrogen sulphide from the gas phase directly by converting, by at least one and preferably pressurized, recycling aπthraquinone AQ-/ anthrahydroqumone AHQ-method (61-64) or other method with similar function, or in combination with the above said methods for production of elementary sulphur S (69), hydrogen Efe (68) and/or hydrogen peroxide H2O₂ (37), with the possible integration of at least one, preferably pressurized, fuel cell (122) method for production of power (20) and steam (123), said steam feeding at least one steam turbine (124) with attached generator (125) for generation of power (2O)₇ with said fuel cell fed by hydrogen (68) preferably produced within the present method, while the rest part of produced chemicals are recycled within the method and/or to be brought out from the method, the fuel gas content of remaining hydrogen sulphide H₂S as well as a part of carbon dioxide CO₂ are absorbed by a recycling alkaline solution (18 A/1 SB) loop followed by desorbing said gaseous chemicals into the reaction chamber (I).

12 Method according to Claim 11 , c h ar a c t er i z e d i n that the AQ-/AHQ-method (61-64) is integrated with production of deh^'gnification Liquors within pulping processes by anthiaquinone/AQ-refiH (67) and/or a part of recycled AQ-flow (65) constitute additives to nearly sulphur free green liquor or low sulphidity green liquor (18A) and elementary sulphur S (69) is added to nearly sulphur free white liquor or low sulphidity white liquor (55) for production of poly-sulphide (58) as a

13. Method according to any of the preceding claims, c h ara c t e r i z e d i n thai when combustion during partial oxidation of residual liquors/products from pulping processes by at least two reaction chambers,, said chambers are operating during quite different process criteria "with the one reaction chamber (IA) mainly acting for split of alkaline and sulphur compounds, while the other reaction chamber (IB) acting during quite different process criteria, essentially for direct conversion/production of high sulphidity white liquor (18B) by adding recovered elementary sulphur S (69) to the other reaction chamber (1-B) of- low- process pressure;, preferably -1,-10 - 4,00 bar (a), -more preferably 1,30 - 2,30 bar (a), of low steam partial pressure, preferably 0,20 - 0,95 bar (a), more preferably 0,30 - 0,55 bar (a), within temperature interval of 900 - 1100⁰C₃ preferably 950 - 970⁰C, whereby the equilibrium reaction during the reaction progress is displaced, which moves a bigger part of the sulphur content, preferably 75 - 95 %, more preferably 85 - 90 %, out with the phase of solid and/or molten material (18B) from said other reaction chamber (IB) as alkaliDe sulphide Na₂S (18B) with the remaining sulphur compound as a part of the gas phase as hydrogen sulphide H₂S, which part of said remaining sulphur content previously and selectively is partially absorbed by all the flow or a part of the black liquor flow (30, 31) before feeding said black liquor into said other reaction chamber (IB), whereupon the gas phase (38B) comprising the rest part of the sulphur content H₂S is pressurized by compressor (82), and brought together with from reaction chamber (IA) leaving flow of fuel gas (38A), preferably by an in-tappmg of expansion turbine (2).

14. Method according to any of the preceding claims, c h a r a c t e r z ϊ e d i n that fibre partial processes within a pulping manufacturing process is integrated with recovering energy and chemicals essentially by the following process steps as a whole or parts thereof:

• Digester pressure unchanged or increased 1 bar, or more.

• Digester spent liquor/black liquor (30, 31) is fed during nearly preserved state of pressure and temperature to a preparatory process step for ordinary or preferably restricted increase of DS-content, preferably up to the level of DS-content where the solubility of sulphate soap and other included chemicals are preserved, which means a DS-content of interval 30 - 50 %, more preferably 35 - 45 % before feeding the reaction chamber (1).

• Not condensable gases NCG (90) preferably integrated with evaporation plant by

^'

• Bleach plant effluent (87) feeding the reaction progress for recovering energy and chemicals.

• Chips pre-heating in at least one chip bin (97) by gas phase comprising the rest content of heat, moisture and chemicals, preferably within a later part of expansion cooling sequence, more preferably by gas phase (45) after completed said expansion cooling sequence.

• Chips pre-treatment in at least one pre-treatment vessel (98) by pressurized gas phase comprising all the hydrogen sulphide HoS-content or a part of said hydrogen sulphide,

- preferably -within expansion-cooling sequence:

• Pulp washing in at least one vessel (99), of all kind of system comprising counter current, co current and radial water flows, by segregated recovery of clean and tempered condensate (33), preferably comprising dissolved carbon dioxide CO₂.

• Bleaching agents comprising nearly sulphide free alkaline NaOH from split of alkaline and sulphur compounds within the present method, as well as oxygen O₂, hydrogen peroxide H₂O₂ and ozone O3 and when appropriate comprising feeding of said chemicals to reaction progress of reaction chamber as a whole or parts thereof.

• Closed cycle for all the recovery plant chemicals, except separation of non process elements NPE, during high process pressure adjusted to the digester pressure, preferably except the reaction chamber (1) process with preferably a higher process pressure, comprising pressurized production of nearly sulphide free white liquor or low sulphidity white liquor (55) as well as high sulphidity white liquor (55A) and nearly sulphide free green liquor or low suipjhidity green liquor (18A) with addition of AQ (65) and nearly sulphide free white liquor or low sulphide white liquor with addition of elementary sulphur S (69) according to claim 12. as a whole or parts thereof according to existing requirements.

15. Method according to any of the preceding claims. c har c t e r i z e d i n that when combustion of a fuel during partial oxidation for production of synthesis gas, with further processing to for example hydrogen peroxide H2O₂, hydrogen H₂, ammonia NH₃ as a whole or parts thereof, and/or processing to methanol CH₃OH, synthetic diesel, dimethylether DME or other mobile fuels, and/or production of said synthesis gas for an integrated Gasification Combined Cycle (IGCC), the expansion cooling through at least one expansion turbine during at least one partial step is applicable as a preparatory gas cleaning step during generation of power (20) or by said expansion turbine ά^isϊώϊteά^~eϊ2cYgy~fόi^

16. Method according to any of the preceding claims, c h ar a c t e r i z e d i n that when combustion dining partial and/or total oxidation of the pulping process sulphite and/or sulphate spent liquor/black liquor, mixed or separate, with recovering chemicals in form of alkaline compounds as a phase of solid and/or molten material (18) and/or into gas phase containing sub-/microscopic (comprising fumes) and visual dust particles- with sulphur compounds essentially into the gas phase as sulphur dioxide SO₂ directly during total oxidation or when reaction progress takes place during partial oxidauortrthe-hydrof en sulphide-H^S is oxidized during the following gas burning (-1C; 12) to said sulphur dioxide, whereupon said sulphur dioxide is selectively absorbed by at least one solution (183) of said alkaline compounds for direct conversion/production of active digesting liquors within sulphite based pulping processes.

17 , Method according to Claim 16, c h ar a c t e r i z e d i n that the recovery of alkaline compounds preferably constitute a sodium hydroxide NaOH-containing carbonate Na-₂Cθ₃-solution (18), alternatively a carbonate Na₂CC>₃-solιirJon (18A), and/or a bicarbonate NaHCO₃-solution (18BB)₃ as a single mixed solution or as carbonate and bicarbonate solutions separately, according to predestinated process requirements, through avoiding or acting for carbonizing by the gas content of carbon dioxide CO₂, preferably during pressurized operation.

18. Method according to any of the preceding claims, c h a r a c t e r i z e d i n that when need for an additional fuel and/or when insufficient amount of recovered chemicals, or when recovering is not possible, for the reaction progress into the reaction chamber and/or for the mill chemical balance, additional suitable make-up chemicals are added as for example magnesium sulphate, magnetite, ammonia, calcium oxide, calcium sulphate, sulphur (69). petroleum coke (103), black liquor (30), sulphate soap (102), sodium sulphate and/or sulphate ash (101) according to existing process requirements, when dry supplied parts preferably takes place pneumatically direct into the reaction progress, by for said reaction progress appropriate gas. preferably by oxygen containing gas as an agent of conveyance.

19. Method according to any of preceding claims, c h ara c t e r i z e d i n that when combustion of a fuel containing chlorides, said chlorides are during the reaction progress converted to hydrogen chloride constituting a part of the gas flow and said hydrogen chlorides are removed as chlorhydric acid by at least one washing step into a scrubber or correspondingly, preferably by cold water, more preferably recovered cooled condensate from the last expansion turbine cooling stage, by a gas wash preferably through at least one liquid ring pump (9) or other devise with corresponding function.

20. Method according to any of the preceding claims, c h ar a c t e r i z e d i n that when combustion of afuel by partial oxidation during a first pressurized reaction progress into at least one reaction chamber, the fuel gas (38) part of chemical energy is utilized for recovering energy and when appropriate also chemicals, when said energy recovery takes place by at least one second combustion, pressurized or atmospheric unit, during total oxidation into said second reaction chamber (1C) or gas boiler (12), or other devise with corresponding function, preferably with additional fuel supply (30C, 21) to said secondary combustion, with the purpose of reheating the flow of gas and/or condensate within the method and preheating the fuel and/or oxidation agent and/or ordinary steam production for mill internal use, preferably high pressure steam (89) feeding at least one steam turbine (120) with power generator (121) for power generation 20, said steam turbine is preferably integrated into the expansion cooling method, said energy recovery as a whole or parts thereof.

21. Method according to any of the preceding claims, c h ar a c t e r i z e d i n that when at least two stage combustion of a fjxst fuel (30, 30A, 30B) by at least one first reaction chamber (1) during partial oxidation followed by at least one second reaction chamber (1C) during total oxidation, when gas phase after partial oxidation (38) is totally burned out into said second reaction chamber, with or without any additional supply of a secoDd fuel (30C) during total oxidation, while produced gases (38, 38C) of respective reaction chambers (1 , 1C) are both said gases cooled by at least one expander turbine step of at least one partial step with completed expansion of integrated gas phases into at least one common expander turbine step of at least orje partial step to for following recovery appropriate counter pressure, preferably down to negative ^"pr^s^ure7vatfdύtø^"^^TO0T:e^"preferabϊyπϊo'wntb nϊxer/?J'δ,02~--θ^"ba^(^)^ΛvLSc ώLfiχϊt.c-Js^r---' are recovered out of reduced gas phase (40/400) as a product 401, aud/or out of oxidizing gas phase (40C/400C) as a product 401 C₇ and/or as a phase of solid and/or molten material (18- 1 SA, 18C), and/or as dust particles and heavy metals into condensate (32, 32C), -with or ^■without addition of heavy metal ^"binding agents (300) into said condensate, as a whole or parts thereof.

22. Arrangement for recovering energy and "when appropriate also chemicals, the recovery of said chemicals comprising a part or parts of: phase of solid and/or molten material, sub-/microscopic (comprising fumes) -and/or visual dust particles^ gas components and as water solutions, from a fuel comprising a part or parts of: hydrogen, hydrocarbon and hydrogen compounds, which arrangement comprising at least one reaction chamber (1) during at least one reaction progress for combustion/thermal decomposition during partial and/or total oxidation by reaction progress within a pressure interval of 2 - 220 bar (a) and a temperature interval of 600 - 3100⁰C, and a device for cooling produced gas containing chemical and/or physical energy by condensation of into said gas vaporized agents and/or compounds, c har a ct e r i z e d i n that the arrangement comprises:

• one or more reaction chambers (1) for realization of the reaction progress.

• said reaction chambers are acting during different process pressures and/or different stoichiometri, which at least one of said τeaction chambers at reducing progress (1) and at least one of said chambers at oxidizing progress (1 C), when preferably the reaction chambers are arranged in series.

• one or more pressurized slag separator/dissolver/quench of phase of solid and/or molten material (18_., 126) arranged after the reaction chamber when watei or water containing agents ϊs added to said device for dissolving said phase of solid and/or molten material before and/or after gas separation, when necessary avoiding carbonation.

• said cooling arrangement comprising one or more expansion turbines (2, 4, 6), when each step comprising one or more partial steps, for gas cooling by condensation of vaporized agents and/or compounds.

• said cooling arrangement comprising one or more turbine steps of expansion cooling and/or partial steps, which can preferably be arranged as one single unit/multistage expander turbine.

^• said cooling arrangement comprising device for elimination of gas content of suWmicroscopic (comprising~rumes) and visual dust^'parαcles^'when said dusVpirύcles ^{" "} constitutes condensation nuclei for vaporized, condensable agents and/or compounds. whereupon the -weight of said dust particles is increased, said dust particles are falling out of the gas phase with transfer of said dust particles into the condensate phase.

• at least one expansion turbine driven generator (3₃ 5, 7) for power (20) production.

• at least one expansion turbine for driving a stationary apparatus, via mechanical and/or hydraulic transmission or correspondingly, as compressor for combustion air (8) and compressor for gas (82) and any kind of heat pump or correspondingly or expansion, turbine drive of mobile machine/apparatus (83A) constituting any kind of means of transport as vehicle on ground, at/into sea and into air.

• said expansion turbine constructed in materials resistant to erosion and/or corrosion at exposed parts, and preferably adapted for relative high steam partial pressure, when and where needed.

• at least one separation device (14, 15, 16) for separation of gas phase and condensate phase after expansion turbine steps and/or partial steps.

• at least one device, preferably pressurized, for recovering chemicals by conveision/thermal decomposition of hydrogen sulphide H₂S, said device preferably comprising pressurized fuel cell (122), of which supply of hydrogen H₂ preferably is produced within said device for recovering said chemicals and for generation of power (20) and high pressure steam (89).

• at least one steam turbine (120) with at least one generator (121) for production of power (20) with for said steam turbine and expansion cooling turbine coordinated arrangement for condensate handling.

• one piping-, fan- and pump-arrangement with control- and regulating device for the flows of gas, steam, condensate, fuel, atomization- and oxidizing agents, comprising possibilities of integration with other arrangements for exchange of media, comprising condensate (120, 151, 321) and not condensable gases NCG (90).

• at least one compressor (8) for feeding compressed air (35) into reaction chamber

(I)-

• one negative pressure/vacuum strengthening arrangement, when needed a plurality of steps, as vacuum pump (10), steam ejector, any kind of Ii quid ring pump (9) or corresponding device as turbo fen. jet of liquid pump, barometric condensate fall leg with water-seal and gas/turbo fan (11) as a whole or parts thereof, comprising possibilities of integration with other needs of arrangement of negative pressure/vacuum as the non condensable gas NCG (90)- system of the evapδfatibτf plant.^"' at least one storage tank (ϊ 9) for expansion cooled condensate (34) preferably from the condensate separation device of the last step and/or partial step of the turbine expansion cooling.

• at least one reaction chamber (1C) or gas boiler (12) for total oxidation/corabustion of fuel gas from preceding reaction chamber (1) during partial oxidation, whereupon said gas boiler preferably is equipped with heat exchanging elements for pre heating suitable media and/or for ordinary steam production-

• at least one condensation device (22) for cooling the flue gas (45), said device comprisiirgrprehearrBgrof-suitable media,- said device-also comprising possibility for recovering the carbon dioxide COj content as being the essential part of said flue gas, said carbon dioxide to be discharged as a stack gas and/or partly returned to the reaction chamber and/or to be brought out and used within other markets after liquefying and/or final waste disposal, as a whole or parts thereof

23. Arrangement according to Claim 22, c h ar a c t e r i z e d i n that the reaction chamber (1) of the reaction progress consists of any kind of known engineering and apparatus technology comprising principles as: combustion chamber, up flow, molten bed, bubbling fluidized bed, fluidized bed and entrained flow, preferably comprising at least one ceramic- and/or cooling tube in-lined reaction chamber, corresponding with said principles of apparatus technology analogous arrangements for separation and handling/treatment of produced phase of solid and/or molten material after the reaction progress with moistening the gas phase before and/or after said separation of said phase of solid aϋd/or molten materiaL

24. Arrangement according to any of Claim 22 or 23, c h ar a c t e r i z e d i n that a fuel burner nozzle of the reaction chamber burner arrangement consists of any kind of known engineering and apparatus technology comprising principles as multi hole nozzle, single hole nozzle, vortex nozzle, venturi nozzle, infra sound nozzle and ultrasound nozzle, either as one single noz2le or as a plurality of nozzles, with steam and/or any kind of gas as atornization- and forcing agents for wet fed fuels and pneumatic fluidized conveyer system when dry fed agents or compounds comprising bio fuels, carbon powder, petroleum coke, sulphur, calcium sulphate, sodium sulphate and sulphate ash, according to existing requirements, with both the feeding systems at the same time or only one of said systems.

25. Arrangement according to any of the Claims 22 - 24, char a c t eri z e d i n that it includes at least one static ajod/or dynamic contact device for selective recovery/absorption of recoverable gas part of the gas phase, which said dynamic contact device is preferably of type rotating device with extremely short time of contact between said gas phase and absorbing liquid, more preferably a rotating device of type liquid ring pump (9), most preferably liquid ring pumps in series to the gas flow counter current fed cooling and sealing liquid constitutes, when appropriate, absorption agent for selective -absorption-of said recoverable gas part, preferably by alkaline solution for said selective absorption of said recoverable gas part, with preferably said cooling and sealing liquid of the last step of said type of liquid ring pump to be cold water for gas washing.

26. Arrangement according to any of the Claims 22 - 25, c h a r a c t e r i z e d i n that after the reaction progress a number of process steps are coordinated in at least one multi functional apparatus (126A, 126B), preferably pressurized, according to the site into the arrangement representing a device for dissolving a phase of solid aod/or molten material and/or for separating gas and liquid phase, further slaking chemicals/substances in oxide form for transmission into hydroxide form, and arrangement for avoiding or acting for carbonizing the chemicals and to be a receiver of additional chemicals- as a whole or parts thereof according to process requirements, said process steps - when needed - during effectual contact during intensive stirring between the phases of gas (40) and liquid (127) through inside the said multi functional apparatus placed concentrically formed intermediate walls (125) creating a form of multi stage liquid-lock, the bottom part of said intermediate walls preferably designed with a saw-toothed performance (125B) for the very best flow distribution said wall turns around.