FI123455B - Procedure for performing pyrolysis - Google Patents

Description

METHOD. FIELD OF THE INVENTION FOR CARRYING OUT PYROLYSIS

The invention relates to a process for carrying out pyrolysis as defined in the preamble of claim 1, wherein a first feedstock is fed to a combustion boiler and a second feedstock is integrated into the pyrolysis reactor, energy fractions are generated from the feedstock in the combustion boiler and gaseous and liquid product fractions.

BACKGROUND OF THE INVENTION

It is known in the art that the pyrolysis product, i. The pyrolysis liquid or pyrolysis gas is produced by dry distillation using pyrolysis techniques from various biomasses or organic materials such as wood, bark, paper, straw, waste, combustible stone, lignite, peat or the like. Pyrolysis is conveniently carried out in an anoxic state at a temperature of about 300 ° C to about 800 ° C.

Typically, using a slow heating rate, a pyrolysis fluid, such as dry wood tar, typically yields about 20-30% by weight. The amount of pyrolysis fluid increases with the rapid pyrolysis method. Rapid pyrolysis processes for the preparation of pyrolysis products and chemicals are known in the art, typically by heating the pyrolysable fuel in a hot oxygen-free mass gas stream by supplying the necessary heating heat to a heating gas, heat exchanger or heat exchanger.

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sand, alumina-based substrates, into the pyrolyser. A bubbling or sand circulating fluidized bed reactor can be used as a pyrolyser. The resulting pyrolysis vapor is condensed 2 to below 150 ° C to form a pyrolysis liquid.

The pyrolysable fuel, e.g., biomass, may be introduced into the drier prior to the pyrolyser to reduce the water content of the resulting pyrolysis fluid. Generally, known tumble dryer, flash or fluidized bed dryers are used in which the drying gas is typically flue gas or water vapor. In addition, it is known to use a steam dryer in which heat is applied to a fluidized bed dryer by means of a hot duct and only water is removed. The temperature is maintained at a level such that no organic compounds are removed.

EP-A-513051 (Ensyn Technologies 15 Inc.) discloses a process and apparatus for the production of pyrolysis fuel from fuels by high-speed pyrolysis with a separate mixing and reactor zone as a pyrolyser. The heat transfer to the fuel particles is accomplished by the use of heat-transporting sand or alumina quartz catalyst having an average particle size of 40 to 500 µm as a heat transfer medium. The method uses an oxygen-free transport gas. The particulate feed material, the oxygen-free transport gas, and the hot heat-transferring particulate material are mixed together at the bottom of the reactor, and the mixture is raised to the reactor portion where the feed material is converted to products, having a contact time of less than 1.0 seconds. Transporting heat

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9 30 the particulate material is separated from the product fractions and recycled to the reactor. In the method, the mass ratio of heat transfer material to fuel is greater than Q_ 5: 1.

£! In addition, an oxidation reaction

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Use of? 35 in order to treat the sand leaving the pyrolyser and the coke produced during pyrolysis. The oxidation reactor burns coke and heats the sand, which is recycled back to the pyrolyser. The oxidation reactor is typically 1: 5 in relation to the fuel power of the pyrolyser. This type of oxidation reactor is designed to burn primarily 5 coke and non-condensable gases produced by pyrolysis only. The heat content of coke and non-condensable gases is then a limiting factor for the mass feed of the pyrolyser based on the energy balance.

The problem with known pyrolysis processes is the need for additional fuel for the pyrolyser and auxiliaries such as a dryer, and the potential migration of water evaporated in the process to the pyrolysis oil. Conventionally, for example, evaporated water in a dryer is condensed or discharged into the open air. When evaporated water contains organic dry distillation products, the use of the process becomes problematic due to environmental hazards, e.g., strong odor nuisances. In addition, known devices do not allow efficient utilization of different process streams, by-streams, and unwanted intermediate / end products in the process.

In addition, it is already known to integrate a pyrolyser and a combustion boiler into a single unit from the same applicant's patent FI 117512.

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PURPOSE OF THE INVENTION

The object of the invention is to eliminate the above-mentioned problems and to provide a novel method for use in the treatment of pyrolysis and its various driving methods.

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cp 30 and optimizing the pyrolysis and energy product distribution in cm. In particular, it is an object of the invention to provide a method for producing industrial

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at the same time, recycling the thermal energy and the pyrolysis product in an environmentally friendly manner

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^ 35 and utilizing the process streams generated in the process.

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SUMMARY OF THE INVENTION

The process according to the invention is characterized by what is claimed.

The invention is based on a process for the flexible production of pyrolysis and energy products and for the realization and enhancement of pyrolysis by feeding a first feedstock or feedstock blend to a combustion boiler and a second feedstock or feedstock blend to a pyrolysis reactor integrated in the feed. energy fractions are formed from the first feedstocks in the form of heat, electricity, steam or gas, and the pyrolysis reactor is formed by rapid pyrolysis to produce gaseous and liquid product fractions. Energy fractions 15 are transferred from the combustion boiler to the pyrolysis reactor by means of heat transfer material heated. According to the invention, the production of pyrolysis product and energy fractions is controlled by optimizing the raw material and its choice such as availability, cost and quantity, product distribution 20 and production cost, market value and quality of at least one product fraction, preferably multiple product fractions, market value and quality. more than one process variable selected from the first raw material, the second raw material, the amount of raw materials, the moisture content of the raw material, the selection of additives, the selection of an additional process step from drying, heat raising step, gasification step, dust separation, reforming, steam reforming, separation of product fractions and solids separation, choice of carrier gas to be used, flue gas, water vapor, air and mixture thereof, carrier gas volume, oxygen content, heat transfer material selection

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among them sand, bedding, alumina-based ma- £! material and other fluidizing material, and process parameters selected from the temperature of the pyrolysis step, the temperature of the additional process step, the residence time in the pyrolysis reactor, the temperature of the boiler, the addition of oxygen, the recycling and recycling of the heat transfer material. Further, according to the invention, the second raw material is mixed with the carrier gas to form a mixture and the heated heat transfer material is introduced into the mixture.

The first raw material is referred to herein as the raw material or mixture of raw materials fed to the combustion boiler. By the second raw material is meant herein the feedstock 10 or the feedstock mixture fed to the pyrolysis reactor. The first and second raw materials may be identical in composition, partially identical, or completely different. In one embodiment, substantially different feedstock is fed to the combustion boiler and the pyrolysis reactor to maximize the efficiency of combustion and pyrolysis and the yield of the pyrolysis product.

Preferably, the process of the invention runs the process as a whole by optimizing the raw material, product distribution, product quantity and quality to be selected. 20 In one application, the proportion of the most valuable product fractions is maximized.

Preferably, the integrated combustion boiler supports the implementation and success of pyrolysis.

In one embodiment of the invention, the raw materials in solid, liquid, vapor or gas form are selected from the group consisting of organic matter, chips, wood chips, wood, bark, sawdust, straw, coal, peat, oil,

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^ combustible rock, lignut, petroleum, biomass, energy-containing waste material, plastics, waste plastics, fuel

Cvj? 30 containing waste, waste fuel / RDF, tall oil, black liquor, organic solvent and

Er their derivatives. In one embodiment,

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the raw material or materials to be selected, e.g., from parallel containers, according to the type of product distribution

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In one embodiment, the energy and pyrolysis product fraction in solid, liquid, vapor or 6 gas form includes pyrolysis gas, pyrolysis vapor, pyrolysis fluid, pyrolysis oil, black liquor, tall oil soap, fuel, chemicals, carbon black, gasification, flammable gas, 5 steam, water vapor, hydrogen, heat and electricity.

In one embodiment of the invention, the gaseous product fractions resulting from pyrolysis are mainly condensed into liquid pyrolysis products.

In one embodiment, most of the energy and pyrolysis product fractions are recycled, recovered, further processed and / or utilized.

Preferably, only a fraction of the energy fractions generated in the combustion boiler are fed to the pyrolysis reactor and other process steps.

In one embodiment of the invention, the heat transfer material is used to transfer an energy fraction, preferably heat, from the boiler to a desired process step, e.g., pyrolysis or desired and predetermined further steps, and / or recovery. In one embodiment, a heat transfer material is supplied to each process step separately. In an alternative embodiment, the same heat transfer material circulates through different steps. In one embodiment of the invention, the heat transfer material is recycled from the incinerator to the pyrolysis reactor and from the pyrolysis reactor through a separation step back to the incinerator.

The heat transfer material is selected from sand, bedding, alumina base material, other fluidizing material and the like.

c5 S5 In one embodiment of the invention, the process cS involves multistep pyrolysis, the first of which

The Er stage is subjected to rapid pyrolysis and the second stage

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forming improved product fractions and / or additional product fractions by an additional step. In one embodiment of the invention, the process o c \ J involves a multi-step pyrolysis, the first step of which involves an additional step and the second step of pyrolysis to form improved product fractions and / or additional product fractions.

The additional step is selected from: drying, raising the temperature, gasification, dust separation, reforming, 5 steam reforming, product fraction separation, and solid separation. The solid separation may include the separation of a heat transfer agent such as sand, carbon, coke, solid particles, or the like.

In one embodiment, the first and second steps 10 are substantially integrated into one entity, e.g., the same device. In an alternative embodiment, the first and second stage devices are connected to each other.

In an alternative embodiment, multi-stage pyrolysis may involve more than two steps.

In one embodiment of the invention, the method modifies the implementation of the pyrolysis step by at least one specific operation selected from raising the temperature, lowering the temperature, selecting a carrier gas, supplying steam, and adding oxygen.

In one embodiment, the pyrolysis gas formed in the first step is conducted to a second step having a temperature substantially higher than in the pyrolysis step. If water vapor is used as the carrier gas for this second stage, a steam reforming reaction occurs, resulting in the decomposition of a large proportion of the tar compounds to hydrogen and carbon monoxide.

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In one embodiment, the heat transfer medium is fed in two steps to the reactor, the drying step c5 and the reaction step. The cS temperatures of the drying step and the reaction step are adjusted separately to optimize product distribution and product quality. In one embodiment,

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raw material fed to the drying step and heat transfer- £! after drying, the material is conducted in a mixture to one another

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^ 35 steps, i.e.. reaction step.

The drying method may be any drying method known per se, for example, low-temperature drying, mixed drying or the like. Part of the thermal energy generated in the combustion boiler may be utilized in drying the fuel to be pyrolyzed. Drying preferably reduces the water content of the pyrolysis product formed, thereby increasing its stability. Water vapor can be recovered from the drying process, which can be utilized, for example, in heat production. In one embodiment, steam is not separated from the drying step.

In one embodiment, the pyrolysis reactor is run as a carburetor-like device. In this case, the temperature in the reactor is higher than normal pyrolysis, and gas yield is maximized in the product mix. In one embodiment, natural gas is added to the reactor as an additive.

In one embodiment, the carrier gas is selected from the group consisting of flue gas, preferably purified flue gas, water vapor, air and a mixture thereof.

In a preferred embodiment of the invention, the carrier gas contains oxygen. Preferably, the pyrolysis is carried out in the presence of oxygen in the pyrolysis reactor.

In one embodiment, a carrier gas containing 1-7% by volume of oxygen is used. Oxygen can increase the shelf life of the pyrolysis product.

In one embodiment, additional oxygen is added to the carrier gas, e.g. in the form of air, to increase the oxygen content. co ^ In one embodiment, the purified gas from the combustion boiler, which recycles

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30 boilers to the pyrolysis reactor. cS In one embodiment, water vapor is used as the carrier gas. And then there's a steam reforming reaction,

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as a result, a large proportion of the tar compounds are degraded in the ve- £! and carbon monoxide.

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In a preferred embodiment, the carrier gas is passed S once through the pyrolysis reactor and fed to the combustion boiler. The carrier gas is not recycled from the pyrolysis reactor outlet to the pyrolysis reactor inlet.

The process parameters are selected from pyrolysis step temperature / temperature in the pyrolysis reactor, additional process step temperature, residence time in the pyrolysis reactor, combustion boiler temperature, pyrolysis feedstock, carrier gas and heat transfer material mixing and flow mixing medium, and recycling of secondary fractions.

In one embodiment, product fractions formed in a combustion boiler and a pyrolysis reactor are divided into products, process side streams, residual streams, waste streams, and / or unwanted fractions. In one embodiment of the invention, most of the side, residual, and waste streams, e.g., condenser residual streams, separation streams and filter streams, feedstock streams, flue gas streams, and the like, are substantially recycled to the incinerator. There is no need to separately adjust the inlet and residual and waste stream feeds and feed rates to the combustion boiler due to the substantially higher feedstock input from the combustion boiler itself.

In one embodiment of the invention, the first feedstock and carrier gas are provided in a mixture and the heated heat transfer material is conducted into the mixture.

In one embodiment, suitable additives are used at various stages of the process. As additives, alcohols such as isopropanol, ethanol or rapeseed methanol ester may be used, in conjunction with a condenser, to improve the performance of the S1 30 condenser and / or product quality. Also, in the context of scrubbers or the like, time-consuming holol based agents can be used to improve the performance of the device. In one embodiment, the catalysts can be used as an additive, e.g. in a pyrolysis reactor or in a combustion boiler, e.g. in a sand cycle, to improve process efficiency and / or product quality.

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The invention enables optimization of process efficiency, costs and product distribution in relation to the price and quality requirements of different products. An advantage of the invention is that the pyrolysis-combustion combination of the invention can be utilized in the manufacture of various and novel products. Thanks to the optimization method of the invention, the pyrolysis reactor may also operate for non-conventional pyrolysis purposes at capacity or at least partially over time. In addition, various additional steps and devices for controlling the product distribution can be easily connected to the pyrolysis reactor. The integrated solution of the invention provides a broader operating framework for different driving modes and for the manufacture of different products.

The process according to the invention can produce both the pyrolysis product and the energy fraction with higher efficiency than known, because the resulting side and waste streams, solid and carbonaceous and non-condensable gases and their energy content can be converted into heat or steam for power generation in the combustion boiler. A part of the thermal energy of the combustion boiler is used in the pyrolysis reactor, in the drying and possibly other process steps of the pyrolysing fuel, and in the combustion of non-condensable gases in the combustion boiler, and most of the thermal energy is conducted eg in steam form. The pyrolysis-oo £ actor and other process steps do not require additional ^ energy supply, but heat from the boiler.

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? 30 energy is sufficient to maintain the process. An advantage of the invention 00cj is that the pyrolysis reactor ϊ combustion boiler combination according to the invention achieves energy self-sufficiency * £! Feeding the optimum fuel blends m ^ 35 to both the pyrolysis reactor and the boiler improves

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The efficiency of the process with respect to the yield of the pyrolysis product and the thermal energy and minimizes the process costs.

The process according to the invention is easy to carry out in production. An integrated combustion boiler has a power supply of 5 and is easy to adjust, for example, in a pyrolysis reactor. The process according to the invention can be used to pyrolyze any product from a suitable raw material. In addition, the process of the invention is easy to control. Coke 10 or similar residual fractions do not accumulate in the process equipment, but can be led to the combustion boiler for incineration and thus do not cause process problems. Therefore, the choice of the raw material does not need to be concerned with its possible coke content.

A further advantage of the invention is that the process coke balance and drying temperature balance do not constitute a constraint on pyrolysis and other process steps.

DETAILED DESCRIPTION OF THE INVENTION

The invention will now be described by means of detailed application examples.

Example 1 25

A process entity according to the invention is formed comprising an incinerator, a pyrolysis reactor and a condenser. The pyrolysis reactor and condenser are integrated, i.e. forming a cohesive unit of C 19, essentially with the combustion boiler. The fuel c \ j is supplied with fuel which is burned ϊ to produce thermal energy. In the pyrolysis reactor Q_, gaseous pyrolysis products are formed by pyrolysis from suitable feedstocks, which are condensed into m.p. 35 liquid pyrolysis products in a condenser.

o c \ j Carry gas is fed to the pyrolysomt reactor. The energy fractions generated by the boiler in the form of heat, water vapor or gas are recovered or part of the heat is recycled to other parts of the apparatus, such as a pyrolysis reactor, in the form of hot heat transfer medium, in this embodiment bedding.

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Example 2 The method of this example is implemented with the process equipment of Example 1.

10 The process uses the best and most suitable portion of the raw material as the pyrolysable material and feeds the inferior portion in terms of pyrolysis into the incinerator. The separation of the raw material is carried out in a manner known per se, e.g. by means of a classifier or an optical separator.

15 Good raw materials for pyrolysis are forest industry residues such as chips, sawdust and bark. However, only the so-called. heartwood without bark provides high liquid yield from dry raw material. The shell thus produces less pyrolysis product, which is more unstable and easily phase-separated. Therefore, the same feedstock should not be fed to the pyrolysis reactor and the combustion boiler. A preferred embodiment is to feed the bark-containing raw material to the combustion boiler for energy production and to the pyrolysis reactor 25 for sawdust to produce the pyrolysis product. In addition, peat or coal is fed into the combustion boiler to satisfy the entire fuel requirement, co δ, Example 3 c \ j 9 30 co c \ j

With equipment according to Erk 1. In this example, the processing is biphasic, in which the steps are combined.

In the first pyrolysis step, the pyrolysis gas formed by the pyrolysis silo is introduced to a second process step having a temperature substantially higher than that of the pyrolysis step. If water vapor is used as the carrier gas for this second stage, a steam reforming reaction occurs, resulting in the decomposition of a large proportion of the tar compounds to hydrogen and carbon monoxide. By this method 5, a gasification gas can be prepared, for example for Fischer-Tropsch synthesis.

Example 4 The method of this example is implemented with the apparatus of Example 1.

Water vapor is used as the carrier gas for the pyrolysis. The steam may be derived from the moisture of the raw material, which is separated, for example, during the drying of the raw material. 15 A steam reforming reaction occurs. The product is a gas that can be combusted or chemically refined, such as ammonia or synthetic fuel. The product gas can be used, for example, in the Fischer-Tropsch synthesis. The moisture of the raw material can be utilized as steam in steam reforming.

Example 5 The method of this example is carried out with the apparatus of Example 25. In this example, the process is a two-step process in which the drying and reaction processes are combined with one another. The heat transfer agent, which is bedding sand, is fed in two steps, the first part in the drying step and ci? 30 second part to the reaction step. The temperatures of the drying step and the reaction step are adjusted separately to optimize the product mix and product quality. The vapor is not separated from the dry phase but only from the condensation of the product gas. c \ j

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q 35 Example 6 o

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14 The method of this example is implemented by the apparatus of Example 1.

In this process, the raw material of the pyrolysis reactor and the carrier gas, which has been purified to a flue gas, are arranged in a mixture and the hot bed sand particles from the combustion boiler are introduced into the mixture of raw material and carrier gas into the pyrolysis reactor. In this case, a region of strong turbulence is formed at the mixing point. flash phenomenon, which allows the pyrolysis to start 10 quickly and efficiently. The sand used, having a grain size greater than 0.5 mm in this application, is substantially heavier than the feedstock for pyrolysis, and therefore acceleration of the sand particles causes a more efficient heat transfer and mixing of the gases to the mixture stream, thereby enhancing pyrolysis.

EXAMPLE 7 The method of this example is carried out with the apparatus of Example-20 kin 1.

By adding a proportion of air and thus an oxygen concentration to the carrier gas, the proportion of the liquid components of the pyrolysis product can be adjusted with respect to the proportion of non-condensable fractions depending on the desired product distribution. The pyrolysis reactor can then be used as a carburetor-like device. Pyrolysis-Combustion Boiler Efficiency and Calorific Value for Gas

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£ are higher than in conventional air gasification ^ because most of the heat can be introduced into the gasification reaction by means of circulating pulp or bed sand.

co C \ 1 ϊ Example 8

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The method of this example is implemented using

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^ 35 with 1 hardware.

o cvj The product gas generated in Pyrolysomn is heated to above 1000 ° C to decompose the hydrocarbons. As a result, the product produces hydrogen and carbon in the form of finely divided fibers. Ko. carbon fibers can be used as an additive, for example in the manufacture of paper due to its high strength. The advantage of the process 5 is the advantageous production of carbon fibers, the utilization of biomass in the production of carbon fibers, and the easy production of hydrogen.

The process according to the invention is applicable in various applications for the preparation of various pyrolysis products and their derivatives and for the production of energy fractions such as thermal energy.

The invention is not limited solely to the above examples, but many variations are possible within the scope of the inventive idea as defined in the claims.

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Claims (11)

1. A method for performing a pyrolysis such that a first blank is measured in a combustion furnace and a second blank in a pyrolysis reactor which is integrated into each other, in the combustion furnace energy fractions are formed of the first blank which is moved from the combustion furnace to the pyrolysis reactor by means of heated heat transfer material and in the pyrolysis reactor a gaseous and liquid product fractions of the second blank are formed by a rapid pyrolysis, characterized in that the second blank is mixed with a carrier gas to form a mixture and the heated The appropriate heat transfer material is led into the mixture, and the production of pyrolysis product and energy fractions is controlled by optimizing the choice, availability, cost and amount of raw material and the product distribution and production costs, value and quality of at least one product fraction by controlling process variables, such as is selected from the group one for 20 solid blank, a second blank, quantities of blank, moisture content of blank, weight of additives, weight of addition process from drying group, temperature rise stage, gasification stage, dust separation, reformation, meadow reform, separation of product fractions and separation of product fractions. substance, vai of carrier gas to be used from the group of flue gas, water vapor, air and their mixture, the amount of carrier gas, the amount of oxygen, vai of o heat transfer material from the group of sand, bed sand, alumina-based material and other flotation materials, and process parameters selected from the CM group pyrolysis stage temperature, additional process chain temperature, residence time in the pyrolysis reactor, combustion furnace temperature, oxygen supply, ateria recovery of the heat transfer material and recovery of section 35 of product and side fractions. CM 2. A process according to claim 1, characterized in that gaseous product fractions which arise during the pyrolysis are condensed mainly to the liquid and pyrolysis products. 3. Process according to claim 1 or 2, characterized in that the blank is selected from the group 5 organic substance, wood chips, wood chips, bark, sawdust, straw, coal, peat, oil, oil shale, lignite, rock oil, biomass, waste material which contains energy, plastic, waste plastic, fuel containing waste, fuel / RDF formed from waste, tall oil, black liquor, organic solvent and their derivatives. Process according to any one of claims 1 to 3, characterized in that the process comprises multi-stage pyrolysis, wherein a rapid pyrolysis is performed in the first stage and improved product fractions and / or additional product fractions are formed by means of an additional stage in the process. second stage. Process according to any one of claims 1 to 4, characterized in that the process comprises multi-stage pyrolysis, the first stage of which is an additional stage and in which the second stage a rapid pyrolysis is performed to form improved product fractions and / or additional product fractions. Method according to any of claims 1-5, characterized in that in the process, the pyrolysis stage is processed with at least one special measure selected from the group temperature control, vai of carrier gas, feed of meadow and supply of oxygen. A process according to any of claims 1 c / j S5, 30 to 6, characterized in that the carrier gas contains co c 2 of oxygen. A process according to any of claims 1 CL - 7, characterized in that the carrier gas is supplied with additional acid. m ^ 35 Method according to any of claims 1 ° -8, characterized in that the majority of the side, residual and waste streams are recirculated to the incinerator. Process according to any of claims 1 to 9, characterized in that heat transfer material is used for moving an energy fraction from the incinerator to the desired process stage and / or for recovery. Method according to any of claims 1 to 10, characterized in that heat transfer material is recirculated from the combustion furnace to the pyrolysis reactor and from the pyrolysis reactor to the combustion furnace via a separation stage. 15 co δ c \ j i CVJ o CO CVJ X DC CL δ r-- LO r-- o o CVJ