CZ290861B6 - Method for energetic employment of solid fuels with pressure gasification and steam-gas cycle as well as apparatus for making the same - Google Patents

Abstract

The invented method for energetic employment of solid fuels with gasification and steam-gas cycle, further with high-temperature purification of synthetic gas and partial recycling of combustion products is characterized in that carbonaceous fuel containing coal and/or a biomass mixture with coal is subjected to gasification through substoichiometric combustion in fluidized and/or transport bed of a particulate mixture of air and recycling portion of combustion products at least in two vertical levels at the total stoichiometric oxygen/fuel ratio ranging from 0.3 to 0.8, at temperature in the range of 700 to 900 degC and operating pressure of 1.0 to 2.4 MPa, whereby temperature in a pressurized gasification reactor is controlled by means of a flow amount and temperature of the recycling combustion products, compressed air, recycling fly ash separated from the synthetic gas and content of water in fuel entering at least in two vertical levels the reactor. The obtained synthetic gas is then subjected to desulfurization and after separation of solids, it is combusted with a temperature of at least 1100 degC. The combustion products are let to expand and after their subsequent cooling being connected with steam generation a portion of the combustion products is recycled. Apparatus for carrying out the above-described method consists of a pressurized gasification reactor (101) being provided with at least two fuel inlets, arranged at different vertical levels and at least two air and recycling combustion products inlets, arranged at levels different from each other and at least one inlet of recycling fly ash and at least one inlet of desulfurizing lime substances and further with synthetic gas outlet (117) that is connected with at least one cyclone (102). The synthetic gas outlet of the last cyclone (102) is connected via at least one filter (203) with a combustion chamber (204) the combustion products outlet of which is connected via at least one gas turbine (205) with a steam boiler (206). Outlet of combustion products from the steam boiler (206) is connected to both a chimney (306) inlet and to recycling combustion products compressor (303) inlet. Outlet of separated solids-fly ash in the cyclone (102) is connected with a fluid divider (104) that is connected with both a fluid closure (103) being connected through the mediation of a channel (111) for fly ash recycling with the gasification reactor (101) and with a fluidized bed chamber (105) to convert CaS to CaCOi3 and CaSOi4 prior discharge of cyclone ash from the system.

Description

Technical field

The invention relates to a method for the energetic utilization of solid fuels, in particular coal and a biomass / coal mixture with a higher water content, using a steam-gas cycle with partial recirculation of the flue gas and an apparatus for carrying it out.

BACKGROUND OF THE INVENTION

Generally, the energy endeavor of solid fuel combustion processes is to maximize the efficiency of converting fuel energy to useful, most often electrical energy, while minimizing both gaseous emissions and minimizing carbon loss from fuel and the harmfulness of solid combustion and gasification residues such as washable heavy metals, some volatile sulfides, etc. The development of combustion methods and increased energy conversion efficiency has led to the introduction of so-called combined cycles (cycles) using not only steam turbines but also gas turbines capable of working with significantly higher temperatures of compressed combustion gases - currently around 1200 Deň: 32 ° C. These facts have led to the development of stepwise processes not only of pressure fluidized bed combustion and gasification of solid fuels with the aim to reach temperatures up to 1250 ° C without negative consequences on the behavior of ash particles, eg softening, melting, etc. without excessive NO _X formation and 'In situ' desulphurisation at 750 to 950 ° C.

From patents RU 2 123 637, WO 0 043 468, WO 0 077 128 and A1, US 6 101 983, US 6 148 599, EP 0 698 726 A2 and others, a number of methods and arrangements of combined cycles using pressurized fluidized bed gasification and combustion are known. solid fuels with high-temperature purification of oxidative flue gases and synthetic gas, which are used in contact with each other in the combustion chamber to raise the gas inlet temperature of the gas turbine.

A typical configuration for such a process, eg advanced, staged PFBC / G, comprises a gasification pressure reactor, a combustion pressure reactor, two independent high-temperature flue gas cleaning lines that often have to operate under different conditions such as temperature, fouling, filter backflow rate etc., problematic transfers of unused residues from the gasification reactor to a combustion reactor, etc., a combustion chamber for contacting the oxidation flue gases with synthetic gas, which suffers from different gas purification conditions and the associated pressure unevenness. The advantage of these technologies is, on the other hand, the possibility of achieving a low butt in the residues from the oxidation technology of pressure combustion and the possibility of oxidation or decomposition of CaS, which was created under conditions of gasification of sulfur-containing fuel.

Further simplification and integration of gasification and combustion in one reactor is solved, for example, in JP II 181 458 A2, where the air and fuel supply is realized at only one vertical level, the reactor using only indirect cooling by generation or superheated steam in the tubes. In such a reactor, a temperature profile with a possible negative reflection in the gas composition is necessarily formed.

Another problem is the humidity of the fuel, which is sometimes solved by integrating fuel drying into pressure combustion and gasification processes such as A-PFBC / G. The drying of the fuel is carried out, for example, by means of hot exhaust gases with a lower oxygen content or by means of hot synthetic gas, see for example U.S. Pat. Nos. 6,148,599 and 5,695,532. A common drawback of these technologies is the release of tar from fuels. tar-containing and difficult to recover energy used to evaporate water from fuel (coal).

-1 CZ 290861 B6

SUMMARY OF THE INVENTION

It is an object of the present invention to simplify the performance of pressurized fluidized bed gasification of coal, coal-biomass blend and coal-waste biomass blend, e.g. sewage sludge, and to more efficiently utilize and convert heat in a combined cycle by partially recirculating flue gas thus the generation of solid waste difficult to deposit or requiring further treatment prior to landfilling.

The gasification process according to the invention improves the possibility of influencing the quality and calorific value of the synthetic gas by using, in contrast to known solutions, eg Japanese patent JP 11 181 450, a vertical division of air, fuel and recirculating flue gas inlets contributing to a more balanced vertical temperature profile in the gasification reactor. and higher gas quality. Unlike known solutions, it uses only direct air cooling, recirculating flue gas and water from the fuel, thus eliminating the risk of corrosion and erosion of the cooling pipes in indirect cooling in the gasification reactor. Furthermore, the design allows and even requires at least partial use of a fuel (coal, coal-biomass mixtures, coal-sewage sludge mixtures, etc.) having a relatively high water content of up to 60% by weight. without problematic integration of fuel drying (coal, biomass) into the process, it increases the overall efficiency of the process by recirculating part of the flue gas, ie by incorporating a practically closed gas cycle with the flue gas compressor and passing through the gas turbine.

According to the invention, the protection of the gas turbine against the increased concentration of alkali metal, heavy metal and vanadium compounds is ensured by the relatively lower operating temperature of the ceramic filter (500 to 700 ° C) from the combustion chamber and optionally by addition of SiO ₂ or SiO ₂ additives. + A1 ₂ O ₃ directly to the gasification reactor and adding some activated carbon or lignite coke adsorbent to the cooled synthetic gas stream upstream of the filter.

The invention solves the reduction of the CaS content in the solids after gasification by contacting a mixture of ash particles, butt, CaCO ₃ , CaS and possibly a small amount of CaO with flue gases containing 2-4% by volume oxygen, above 12% by volume H ₂ O and above 8 % by volume of CO ₂ at temperatures of 500 to 800 ° C and pressures above 1 MPa. If there is a relatively significant amount of butt in the remainder, it is also possible to add some air to the flue gas to increase the oxygen concentration.

Both cyclone ash and filter fly ash are recirculated to provide less carbon butt.

The principle of the invention is that the solid fuel containing coal and / or the biomass / coal mixture is gasified in the fluid and / or transport layer of the particulate mixture by a mixture of air and recirculating flue gas at at least two vertical levels at total oxygen / fuel stoichiometric combustion ratio. 3 to 0.8, a temperature of 700 to 900 ° C and an operating pressure of 1.0 to 2.4 MPa, the resulting synthetic gas is desulphurized and after separation of the solid particles, it is combusted to a temperature of at least 1100 ° C, leaving the flue gas to expand and Subsequent cooling associated with steam production recirculates a portion of the steam.

At least 30 wt. of the feed fuels in the form of a paste with a water content of less than 60% by weight, all fuels containing reactive lignite or lignite or a reactive coal-biomass mixture or a reactive coal-bio-waste mixture have an average dry calorific value greater than 15MJ / kg, average ash content in dry state below 30% by weight, sulfur and nitrogen content in dry state below 1,5% by weight, vanadium, arsenic and lead content in dry matter individually below 100 mg / kg, chlorine content in dry matter below 500 mg / kg of fuel.

The temperature in the pressurized gasification reactor is reacted by the amount and temperature of the recirculating pressurized flue gases entering the reactor and the cyclone ash separator, by the pressure temperature

% By mass flow of the cooled ash from the fluidized bed to the gasification reactor and also partially by a water content of 30 to 60 wt. in the fuel entering the gasification reactor.

The desulphurization of the synthetic gas is carried out under pressure gasification conditions by means of an independent supply of calcium material, preferably ground limestone with a CaO content above 30% by weight, an MgO or SiO ₂ content or Al ₂ O ₃ above 5% by weight, which is added according to the content. sulfur in the fuel such that the total molar Ca / S ratio under the gasification conditions is greater than or equal to 1.5.

Bottom ash from the gasification reactor and a portion of the ash cyclone, recirculated before discharge to the atmosphere is subjected at pressures above 1 MPa contact with the gas - a mixture of flue gas and air with an oxygen content of 3-10 vol.%, Based on the content of the carbon unburned carbon and the content of H ₂ O and CO ₂ at 500 to 800 ° C so that the CaS present in the waste ash mixture is partially oxidized to CaSO ₄ and partially converted by CO ₂ and H ₂ O to CaCO ₃ .

The separation of dust particles in the synthetic gas downstream of the cyclone (s) is carried out after cooling said gas on the filter (s) at a temperature of 500 to 700 ° C.

With a content of carbon butt in the dust trapped on the filter less than 6 wt. The carbon-based adsorbent (e.g., active coke) is added to the gaseous stream prior to the filter (s) so that the total carbon content of the entrapped ash is 6-12 wt.

At a molar ratio (CaO + K ₂ O + Na ₂ O) / SiO ₂ in fuel ash greater than 1 and with a content of SiO ₂ in the limestone below 5 wt%, additive is added to the pressure gasification (eg together with the calcium material) a SiO ₂ -containing substance or a mixture containing Al ₂ O ₃ + SiO ₂ such as silica, kaolinite, crushed fireclay, fluidized-bed ash containing SiO ₂ above 30 wt. in a pressure amount such that the molar ratio (CaO + K ₂ O + Na ₂ O) of the fuel + additive / SiO ₂ of the fuel + additive bel is less than 1.

The combustion chamber downstream of the filters is supplied with synthetic gas at a temperature of 500 to 700 ° C, preheated air at a temperature of greater than 350 ° C and possibly also natural gas, resulting in contact and combustion to produce flue gas at a temperature above 1100 ° C. of oxygen in the flue gas after the gas turbine is 2 to 4% vol.

Part of the cooled flue gas temperature of 120 to 180 ° C and the oxygen content of 2 to 4 vol.% Under the steam boiler is fed to the combustion compressor for partial recirculation of the exhaust gases, and according to the purity of the flue gas is used to remove e.g. H ₂ SO ₄ parts of SO ₂ and NO _X from the flue gas stream prior to flue gas compression activated carbon, or active coke made from brown coal. Thus, most of the H ₂ SO ₄ vapors can be captured by the SO ₂ portion and the NO _X portion, which could be corrosive at a later deeper cooling of the compressed recirculating flue gas. The spent, saturated filter can be disposed of by grinding and combustion / gasification in the main reactor. The recirculating flue gas circulates in a closed gas cycle and, through passage through the flue gas boiler, but also through the gas turbine, achieves higher efficiency in converting thermal energy into useful electrical energy than using a simple steam cycle. In a steady state process, the exhaust gas compressor may be driven, for example, by a steam turbine and the air compressor may be driven by a gas turbine. Natural gas as an additional, equalizing fuel can be used to fine-tune the gas inlet temperature at lower power levels or not to pre-heat the air entering the afterburning chamber and also to better start the system. An additional air compressor can prevent unnecessary throttling of the compressed air when supplying the system with compressed air at different pressure levels.

The apparatus comprises a pressurized gasification reactor having at least two fuel inlets arranged at different vertical levels and at least two vertically different air and recirculation flue gas inlets and at least one desulphurizing lime substance inlet and a synthetic gas outlet connected to the particulate separators and subsequently to a combustion chamber whose flue gas outlet is led through a gas turbine to a steam boiler of which

The steam generated is expanded in a steam turbine and the flue gas outlet downstream of the steam boiler is divided into a chimney outlet and a compressor system for recirculating part of the flue gas.

Further, the apparatus comprises a cyclone (s), a fluid divider and a fluid closure to recirculate a portion of the ash, unreacted carbon and lime matter separated in the cyclone back to the pressurized gasification reactor using recirculated flue gas or compressed air mixtures thereof and a fluidized chamber to convert CaS by oxidation and reaction with H ₂ O and CO ₂ before discharging from the system.

A ceramic filter or a system employing ceramic filters with periodic dust removal is used to collect fine particles.

The apparatus comprises heat exchangers, e.g., connected to a steam turbine steam circuit, to cool the synthetic gas stream prior to filtration on the ceramic filters, to cool the compressed recirculating flue gas stream and the compressed air stream downstream of the respective compressors to the desired temperature.

An example of an embodiment of the invention

The attached drawing shows the circuit diagram of the individual apparatuses in the device according to the invention, including the guiding of the individual media. In a pressurized gasification reactor 101, fuel supplied at a minimum of two different vertical levels is combusted and gasified at a pressure of 1.0 to 2.4 MPa. The gasification medium is both compressed air and a recirculating portion of the compressed flue gas. The compressed air is supplied by a compressor 401, optionally with an additional blower or compressor 405, and the compressed flue gas is supplied by a flue gas compressor 303. Vertically different gas and fuel feeds provide a more even vertical temperature field in the reactor 101. The produced synthetic gas with entrained particles is fed to a cyclone or series of cyclones 102 in which coarser particles are separated (about 3 to 6 µm). Cyclone-separated ash particles with butt, CaCl 3, CaSO _4, and CaS (CaO) are partially cooled in the fluid separator 104 and partially oxidized by fluidizing recirculating flue gas or a mixture of flue gas with air. By means of a fluid shutter or other type of shutter 103, the particles are conveyed through the recirculation channel 111 to the gasification reactor 101. From the separator 104, the particulate material is also conveyed to the fluid chamber 105 for the conversion (destruction and oxidation) of CaS by recirculating flue gas or mixtures thereof with compressed air. Thus, at a temperature of 500 to 800 ° C, waste 115 is produced only with a low content of carbon butt and CaS. The coarse ash is discharged from the bottom of the reactor 101 through the bottom ash cooler 106, where the carbon and CaS content of the waste is also reduced by the flue gas exiting the flue gas cooler 304 or recirculated flue gas / air mixture into the ash chamber feeder 107 and further out of the system as waste 114. The gas exiting the cyclone 102 is fed to a synthetic gas cooler 201 where the produced gas is cooled from 700 to 900 ° C by, for example, a steam superheater or the heating of pressurized air from the heater 402 through the inlet 403 to the combustion-afterburner chamber 204. The cooled gas is passed to the fine filter 203. With a very low butt content in coal and biomass ash, a carbon adsorbent, such as activated carbon or active coke, is added at 202. At low SiO ₂ content in fuel ash and limestone, an additive with a higher SiO ₂ content is added to the gasification reactor 101. The dust trapped in the filter 203 is recovered by the backflow of inert gas or purified synthetic gas and further passed through the fly ash system 113 through the fine ash recirculation line 112 to the fluid separator 104. Part of the fine filter dust (typically 20 to 50 wt%) is discharged from the system as solid waste 116. Pure synthetic gas free of dust and vapors of alkali and heavy metal compounds is led to the afterburner, combustion chamber 204, where the combustible gas components (CO, H ₂ , CH ₄ , C _x H _y ) are burned by preheated air at a temperature above 350 ° C (e.g. 500 ° C) conducted through inlet 403 and by means of natural gas through inlet 501 to achieve the desired higher temperature. Accordingly, depending on the content of combustible components, the degree of preheating of the synthetic gas and air and the flow rate of natural gas, the temperature of the flue gases typically rises to 1100 to 1300 ° C. The hot flue gas enters

The gas turbine 205, which can also drive a steady state compressor 401 to compress the air. The expanded flue gas with an oxygen content of 2 to 4% by volume and at a temperature of 450 to 750 ° C enters the waste heat boiler 206 where it transfers heat for steam production to drive the steam turbine 207. and recirculated flue gas in air cooler 404 and flue gas cooler 304, in a closed steam cycle with steam turbine 207, condenser 208 and condensate pump 209 are also connected. Further, the flue gas at a temperature of 120 to 180 ° C exiting the boiler 206 may be driven by the exhaust fan 301 to the chimney 306.

A portion of the flue gas is routed through a line 302 of activated carbon or lignite coke to a flue gas recirculation compressor 303 where the flue gas part is compressed to a pressure higher than operating pressure to control flow rates in the various flue gas supply lines to the gasification reactor 101. a fluid divider 104, a fluid chamber 105 for converting CaS, etc. Depending on the cooling requirements of the reactor 101, the chambers 103, 104, 105 and the bottom ash cooler 106, some or all of the recirculated flue gas flow may be cooled in the flue gas cooler 304. Similarly, the air compressed by the compressor 401 can be cooled in the air cooler 404 before entering the gasification reactor 101, the fluid divider 104, and other chambers.

Example of technological process

The fuel is brown, reactive coal of the following composition in a dry, anhydrous state: ash 10% by weight, combustible 90% by weight, hydrogen 4.5% by weight, carbon 62% by weight, sulfur 0.5% by weight, nitrogen 0.7% by weight, oxygen 22.3% by weight, chlorine 350 mg / kg, V, As and Pb contents individually less than 15 mg / kg. The calorific value of the anhydrous coal is 21 MJ / kg. The (CaO + K ₂ O + Na ₂ O) / SiO ₂ ratio in ash is 0.8. The particle size of the coal is below 2 mm. The desulphurizing calcium material is ground limestone with a content of: 42.5 wt. % CaO, 0.7 wt. MgO, 15 wt. % SiO ₂ and 3.5 wt. A1 ₂ Oj.

Gasification is carried out by supplying 0.7 times the stoichiometric oxygen demand in the air and the recirculating portion of the flue gas. Total gasification is supplied to the pressure reactor 70 500Nm ³ / hr of air and 90 about 000 nm ³ / h of recirculated exhaust gas with 3 vol.% Oxygen. In total, 20 tonnes / hour of anhydrous coal and 700 kg / hour of limestone are fed to the gasification reactor. The coal is fed into a cylindrical reactor having a total height of 22 m and a cone height of 5 m and an upper cylindrical portion of 3.2 m diameter at a total of three vertical levels. At the bottom and in the region of about 7 m high above the distributor, coal is added in the form of an aqueous slurry with a water content of 45% by weight, mechanically comminuting the slurry into smaller portions before entering the gasification reactor. delivers coarser, dry fuel and a particle size of 1 to 4 mm. At the lower and middle level, 14.54 tons / hour of coal suspension are supplied, i.e. 8 tons / hour of anhydrous coal, at the upper level, 4.7 tons / hour of coal with 15% moisture are supplied, and 4 tons / hour of anhydrous coal. coal. A total of 31,000 Nm ³ / h of air and 40,000 Nm ³ / h of air and 40,000 Nm ³ / h of flue gas are supplied at the bottom (including air and flue gas for recirculation and ash cooling). 25 000 Nm ³ / h air and 32 000 Nm ³ / h recirculation flue gas with 3 vol% oxygen are supplied in the central part and 14 500 Nm ³ / h air and about 18 000 Nm in the upper part about 12 m above the distributor. ³ / hour flue gas with 3% oxygen by volume.

Limestone is fed about 6 m high above the distributor. The temperature in the gasification reactor is 830 to 870 ° C, the average temperature is about 850 ° C, the working pressure is 1.6 MPa, the linear gas velocity in the upper part of the reactor is about 1.7 m / s. The inlet air temperature is about 100 ° C and the inlet flue gas temperature is about 150 ° C.

The synthesis gas is desulfurized with limestone, the desulfurization degree at a molar Ca / S ratio of 1.7 is about 70% by volume. The composition of the synthetic gas behind the cyclones is about 14.4% by volume CO ₂ , 17.7% by volume H ₂ O 3.5 vol.% CO and 3.85% _H2. Concentration of simé compounds (mainly

-5GB 290861 B6

H ₂ S + COS + S ₂ ) in the synthetic gas downstream of the filter reaches about 100 to 110 ml / m ³ . About 20 to 24 wt. Nitrogen from the fuel is converted to NH ₃ , a very small part to HCN and the remainder mainly to elemental nitrogen. The concentration of ammonia in the synthetic gas downstream of the filter is about 110 to 130 ml / m ³ .

Synthetic gas is de-dusted by passing through cyclones. In the cyclones, the ash removed from the desulphurisation and underburden are collected in a fluidized bed separator, where the material (ash, underburden and desulphurization residues) is returned to the gasification reactor through the fluidized bed and to the fluidized bed for CaS oxidation and conversion. The ratio of the mass flow of the separated material into the gasification reactor to the mass flow into and out of the system is about 4: 1. The original CaS concentration (60:40 at a CaSO ₄ / CaS molar ratio) decreased by about a quarter by passing through the fluid chamber at 650 ° C.

The flow rates of ash and residues from the gasification reactor are 10 wt. % as bottom waste ash product, 75 wt. % as cyclone fly ash passed through the fluidized bed for CaS conversion and about 15 wt. like filter dust. Due to the content of carbon butt in the dust on filters greater than 6 wt. no carbon adsorbent was added, and due to the relatively higher SiO ₂ content in the coal ash, silicon dioxide was also not added. Overall, about 2840 kg of solid waste / hour was produced, containing about 19 kg of CaS, about 120 kg of carbon butt, and about 20 kg of CaO.

Due to the content of iron and some heavy metals, CaS helps to stabilize these metals in the form of sulfides. The hydraulic nature of the limestone after passing through the high temperatures and the partial content of CaSO ₄ help these residues to cure hydraulically when water is added. Synthetic heat gas of about 68,000 MJ / h (output 18.9 MW). Thereafter, said gas is fed to ceramic filters to purify fine dust. The synthetic gas outlet from the sequins (temperature 600 ° C, about 193,000 Nm ³ / h) is fed to the combustion chamber where it is contacted with preheated air (flow rate about 93,500Nm ³ / h, heat about 550 ° C) and natural gas, with a flow rate approximately equivalent to 2000 Nm ³ / h of methane.

The flue gas temperature at the outlet of the combustion chamber is about 1150 ° C. Hot pressurized flue gas (flow rate of about 282,000 Nm ³ / h) expands in two parallel gas turbines, where one turbine can be shut down at less power. The expanded flue gas with an oxygen content of about 3% and a temperature of about 600 ° C is recovered energetically in a waste heat boiler, where the flue gas is cooled to about 150 ° C. In a steam boiler approximately 191,000 MJ / h (53 MW output) is extracted from the flue gas.

Combustion gases containing 3% by volume of oxygen, about 13% by volume of CO ₂ and about 16.2% by volume of H ₂ O are further divided into chimney flow (about 192,000 Nm ³ / h) and recirculating flue gas flow (about 90%). 000 Nm ³ / h), which is led through a filter with brown coal active coke to the compressor for recirculation of the flue gas. The exhaust gas temperature at the compressor outlet is about 500 ° C. This temperature is adjusted to the inlet temperature of the gasification reactor of 100 to 400 ° C by means of a condenser connected in the steam circuit. The compressed air required for gasification (substoichiometric combustion) of about 70,500 Nm ³ / h and for the combustion of low calorific synthetic gas and natural gas in the combustion chamber of about 93,500 Nm ³ / h is obtained by a compressor. The compressed air temperature at the compressor outlet is about 350 to 400 ° C. The air is cooled to about 100 ° C in the air cooler before entering the gasification reactor.

Claims (13)

PATENT CLAIMS A method for the energy recovery of pressurized gasification solid fuel fuels with a partial gas recirculation cycle, characterized in that the solid fuel containing coal and / or a biomass / coal mixture is gasified by substoichiometric combustion in the fluid and / or particulate transport layer with air mixture and recirculating portion flue gas supplied at a minimum of two vertical levels at a total oxygen / fuel stoichiometric ratio of 0.3 to 0.8, a temperature of 700 to 900 ° C and an operating pressure of 1.0 to 2.4 MPa, the resulting synthetic gas is desulphurized and solids separated The flue gas is allowed to expand and, after subsequent cooling associated with steam production, a portion of it is recirculated. The method according to claim 1, characterized in that at least 30 wt. of the solid fuels supplied, the fuel is in the form of a paste with a water content of less than 60% by weight, all fuels containing reactive lignite or lignite or a reactive coal-biomass mixture or a reactive coal-bio-waste mixture have an average dry calorific value higher 15 MJ / kg, average dry ash content below 30% by weight, dry sulfur and nitrogen content below 1,5% by weight, vanadium, arsenic and lead dry matter individually below 100 mg / kg, chlorine content dry matter below 500 mg / kg. The method of claim 1, wherein the temperature in the pressurized gasification reactor is reacted by the amount and temperature of the recirculating pressurized flue gases entering the reactor and the cyclone ash separator, the compressed air temperature, the mass flow of cooled ash from the fluidized bed reactor to the gasifier. partially with a water content of 30 to 60 wt. in the fuel entering the gasification reactor. Method according to claim 1, characterized in that the desulfurization of the synthetic gas is carried out under pressure gasification conditions by means of an independent supply of calcium material, preferably ground limestone with a CaO content above 30% by weight, an MgO or SiO ₂ content or Al ₂ O ₃ over 5% by weight, which is added according to the sulfur content of the fuel so that the total molar Ca / S ratio under the gasification conditions is greater than or equal to 1.5. Method according to claim 1, characterized in that the bottom ash and cyclone ash from the gasification reactor are subjected to a gas mixture of recirculating flue gas and air having an oxygen content of 3 to 10% by volume and an H content before being discharged into the atmosphere at pressures above 1 MPa. ₂ O and CO ₂ at temperatures of 500 to 800 ° C so that the CaS present in the waste ash mixture is partially oxidized to CaSO ₄ and partially converted by CO ₂ and H ₂ O to CaCO ₃ . Method according to claim 1, characterized in that the separation of the dust particles in the synthetic gas after the cyclone (s) is carried out after cooling said gas by filtration at a temperature of 500 to 700 ° C. 7. A process as claimed in any one of claims 1 to 6, wherein the content of carbon butt in the dust retained on the filter is less than 6% by weight. before the filtration, a carbon-based adsorbent is added to the gaseous stream so that the total carbon content of the entrapped ash is 6 to 12 wt. Process according to Claims 1 to 7, characterized in that at a molar ratio (CaO + K ₂ O + Na ₂ O) / SiO ₂ in fuel ash greater than 1 and at a SiO ₂ content in limestone below 5% by weight, additive containing SiO ₂ or Al ₂ O ₃ + SiO ₂ such as silica, kaolinite, crushed fireclay, fluidized-bed ash with SiO ₂ content above 30 wt. in a pressure amount such that the molar ratio (CaO + K ₂ O + Na ₂ O) of the fuel + additive / SiO ₂ of the fuel + additive is less than 1. -7EN 290861 B6 9. The method according to claims 1 to 8, characterized in that the combustion chamber downstream of the filters is supplied with synthetic gas at a temperature of 500 to 700 [deg.] C, preheated air at a temperature of greater than 350 [deg.] C and optionally natural gas. whereby after contact and combustion, flue gases with a temperature above 1100 ° C are generated, 5 wherein the total average oxygen content of the flue gas after expansion in the gas turbine 2 to 5 4% vol. Method according to claims 1 to 9, characterized in that a portion of the flue gas is contacted after expansion and cooling in a steam boiler at a temperature of 120 to 180 ° C and an oxygen content of 2 to 4% by volume. 10 with activated carbon or activated coke made of brown coal and compressed. An apparatus for carrying out the method according to claims 1 to 10, characterized in that it comprises a pressure gasification reactor (101) provided with at least two fuel inlets arranged at different vertical levels and at least two vertically different air inlets 15 and recirculating flue gas and at least one recirculated fly ash channel (111) and at least one desulphurizing lime material inlet, and further removing (117) synthetic gas from the reactor (101) connected to the at least one cyclone (102); ) is connected via at least one filter (203) to a combustion chamber (204), the flue gas outlet of which is connected via at least one gas turbine (206) to the steam boiler 20 (206), and the flue gas outlet of the steam boiler (206) is connected; the inlet to the chimney (306) and the inlet to the recirculating flue gas compressor (303), the outlet of the separated fly ash particulate from the cyclone (102) is connected to a fluid divider (104) which is connected to the fluidized bed (103) a fly ash recirculation channel (111) with a gasification reactor (101) and a fluid chamber (105) to convert CaS to CaCO ₃ and CaSO ₄ before discharging 25 cyclone fly ash from system. Device for carrying out the method according to claim 11, characterized in that a synthetic gas cooler (201) and an activated carbon dispenser (202) are arranged between the cyclone (s) (102) and the filter (203). Method for carrying out the method according to claims 1 to 12, characterized in that the generated steam output from the steam boiler (206) is connected via a heat exchanger in the synthetic gas cooler (201) to a steam turbine (207) connected via a condenser (208), pump (209) condensate and heat exchangers in cooler (304) recirculating flue gas and in cooler (404) 35 with the inlet of the steam boiler (206).