EP1399527B1 - Method and device for the pyrolysis and gasification of material mixtures containing organic components - Google Patents

Abstract

The invention is used for the pyrolysis and gasification of material mixtures containing organic components. The organic materials or the material mixture containing organic components are brought into contact with a heat transfer medium, preferably the ash from a combustion reactor, and pyrolysed in a pyrolysis reactor, preferably a shaft reactor. The coke which is generated by pyrolysis is combusted with an air supply in a combustion reactor, preferably in a fluidized bed reactor. The condensable components of the crude gas which is generated by pyrolysis are cracked in a cracking reactor, preferably by means of a catalyst. In order to improve said method, the heat transfer medium is transported using overheated steam (50) as a fluidizing medium.

Description

The invention relates to a process for the pyrolysis and gasification of mixtures containing organic constituents, and to an apparatus for carrying out such a process.

These mixtures may be, in particular, household or household-type waste, as well as products derived from domestic or household waste.

Methods and apparatus for pyrolysis and gasification of organic substances are already known. The DE-PS 197 55 693 discloses a process for the gasification of organic substances, in which the organic substances are passed into a pyrolysis reactor, in which they are kept in contact with a heat transfer medium, whereby a pyrolysis takes place. The pyrolysis reactor is a moving bed reactor or rotary drum. The pyrolysis products consist of pyrolysis gases with condensables and a solid carbonaceous residue. The solid carbonaceous residue and the heat transfer medium are fed to a furnace in which the carbonaceous residue is burned and the heat transfer medium is heated and returned to the pyrolysis reactor. The tarry pyrolysis gases are reheated in a second reaction zone in such a way, that a purified synthesis gas with a high calorific value is obtained. This is done in such a way that the tar pyrolysis gases are passed into an indirect heat exchanger in which they react with a reagent, such as water vapor. The combustion exhaust gases are passed through the indirect heat exchanger in such a way that their heat content is used for the reaction of the pyrolysis gases with the reagent. The ash of the solid carbonaceous residues withdrawn from the furnace and the heat transfer medium are returned to the entry end for the organic material in the pyrolysis reactor.

The DE-OS 199 30 071 discloses a method and apparatus for pyrolysis and gasification of organic matter in which the organics are introduced into a drying and pyrolysis reactor in which they are contacted with the fluidized bed material of a combustion fluidized bed, whereby drying and pyrolysis takes place, in which the organic substances are converted into water vapor from the drying and pyrolysis products. The pyrolysis products consist of gases with condensable substances and solid carbonaceous residue. The solid carbonaceous residue, optionally with portions of the water vapor and the pyrolysis gases with condensables, and the fluidized bed material are fed back into the combustion fluidized bed, where the carbonaceous residue of the organics is burned, the fluidized bed material is heated and recycled to the pyrolysis reactor. The water vapor from the drying and the pyrolysis gases with condensable substances are aftertreated in a further reaction zone in such a way that a product gas having a high calorific value is formed. The combustion fluidized bed, in which the pyrolysis residues are burned, is operated as a stationary fluidized bed. The pyrolysis gases are passed to an indirect heat exchanger in which they optionally react with a reactant such as water vapor, oxygen or air or a mixture thereof. The combustion exhaust gases are brought into contact with the indirect heat exchanger in such a way that their heat content is used for the reaction of the pyrolysis gases with the reagent.

In the prior art method according to DE-PS 197 55 693 and also in the method according to the priority earlier German patent application 199 30 071.2 In each case, an indirect heat exchanger is used, to which the heat of the combustion exhaust gases is supplied and through which the pyrolysis gases are passed. However, this procedure and the apparatus required for carrying out such a method are disadvantageous.

The prioritized, not previously published German patent application 100 33 453.9 relates to a method and apparatus for pyrolysis and gasification of mixtures containing organic constituents. The present invention is particularly well suited for use in a method and / or apparatus according to this German patent application.

In the method according to the German patent application 100 33 453.9 For example, the organic substances or the substance mixture which contains organic constituents are brought into contact and pyrolyzed in a pyrolysis reactor with a heat transfer medium from a combustion reactor. The pyrolysis reactor is preferably a shaft reactor. As a combustion reactor, a fluidized bed reactor is preferably used. The heat transfer medium is preferably formed by the ash from the combustion reactor. But it is also possible to use another heat transfer material or fluidized bed material. The heat transfer medium or the fluidized bed material may contain ash from the combustion reactor or consist exclusively or virtually exclusively of this ash. It is advantageous if the organic substances are brought into contact with the heat transfer medium in that they are mixed together. The organic substances and the heat transfer medium are brought into contact or mixed in the pyrolysis reactor and dried and pyrolyzed. The pyrolysis coke produced by the pyrolysis is burned in the combustion reactor or fluidized-bed reactor under air supply.

The crude gas or its condensable constituents produced by the pyrolysis are cleaned or cracked in a cracking reactor. Preferably, this purification or cracking is carried out by a catalyst which is provided in the cracking reactor. This cleaning or catalytic purification or cracking is preferably carried out with the addition of water vapor.

The method according to the German patent application 100 33 453.9 is particularly suitable for the pyrolysis and gasification of a mixture of substances that has been obtained from household waste or household waste. This is preferably a mixture of substances which has been produced from domestic waste or household waste similar to the following process: The household waste or the household waste similar waste are first pretreated if necessary, in particular crushed. Then they are composted in closed containers under forced ventilation, whereby the organic components are degraded. After a period of time, for example, seven days - after which time the more readily biodegradable components are typically wholly or substantially degraded - the composting is halted by drying. The material is dried to a residual moisture of at most 15%. It can then be retreated if necessary. Such a material is marketed under the name Stabilat ^®.

In a pyrolysis, especially in the process according to the German patent application 100 33 453.9 , It is generally necessary to withdraw from the combustion reactor or fluidized bed reactor or fluidized bed furnace, the heat transfer medium, in particular hot ash, and supply one or more pyrolysis. It should be noted that neither pyrolysis gases from the pyrolysis in the combustion reactor (fluidized bed reactor, fluidized bed furnace) may still come flue gases from the Combustion reactor (fluidized bed reactor, fluidized bed furnace) may enter the pyrolysis reactor.

A mechanical promotion of the heat transfer medium or the hot ash with moving machine parts is not preferable due to the high temperatures or ash temperatures of 900 to 950 ° C and the abrasive behavior of the heat transfer medium and the ash and because of the associated significant heat losses.

In the field of circulating fluidized bed combustors, it is known to use a so-called fluidized siphon. This consists of a downpipe and a container with overflow. The hot heat transfer medium (for example, ash) is collected in the downpipe, there forms a moving bed and slips into the container. With the help of air, the container is flown over a nozzle bottom located on the nozzle bottom, so that a fluidization of the slipping from the downpipe heat transfer medium is achieved and the heat transfer medium can be withdrawn from the overflow of the container. By the pressure loss of the fixed bed in the downpipe, the desired sealing function is achieved. The fluidization of the siphon, the promotion of the hot medium is achieved in a subsequent reactor. As in fluidized bed combustion oxidizing operating conditions exist in which air is added anyway, the air constituents of the fluidizing agent "air" do not disturb the process.

When using in the DE-A-100 33 453 described method is the use of air as a fluidizing agent for the transport of the heat transfer medium or the ash in the cracking reactor or in the pyrolysis reactor disadvantageous because in this case, on the one hand oxygen and on the other hand nitrogen in the process would be introduced. This is contrary to the purpose of the in the DE-A-100 33 453 to produce a synthesis gas as undiluted and as high as possible. The use of air and / or inert gases as a fluidizing agent is not useful under these circumstances.

From the DE 24 48 354 A is a method for producing gas, tar and steam from coal known in which fine coal in a degassing zone with a heat transfer medium in contact and degassed. The remaining after degassing carbon is burned in a fluidized bed chamber with air. The resulting from the degassing raw gas is withdrawn and fed to a gas purification and gas separation. The heat transfer medium is fed via a siphon of the fluidized bed chamber, wherein steam is used as the siphon drive gas.

The DE 196 29 289 A discloses a siphon for conveying fine-grained solids into which a lance projects. A gas flow through the lance allows partial fluidization of the accumulated solid in the siphon.

From the GB-A-1 484 130 is a method for pyrolysis of sludge or waste is known, in which the heat transfer medium can be promoted by means of superheated steam.

The object of the invention is to propose an improved process for the pyrolysis and gasification of mixtures containing organic constituents, as well as an improved apparatus for carrying out a process for the pyrolysis and gasification of mixtures containing organic constituents.

In a method for pyrolysis and gasification of mixtures containing organic constituents, this object is solved by the features of claim 1. A device according to the invention is the subject of claim 15. Advantageous developments of the method according to the invention and of the device according to the invention are described in the subclaims.

According to the invention, the heat transfer medium is conveyed by means of superheated steam as a fluidizing agent. This is done by a fluidized siphon. The transport of the heat transfer medium or the ash from the combustion reactor (fluidized bed reactor, fluidized bed furnace) to the pyrolysis reactor (shaft reactor) is carried out by or at least in cooperation with superheated steam as the fluidizing agent.

Advantageous developments are described in the subclaims.

Preferably, the steam is heated with energy from the combustion of the pyrolysis coke. Instead or in addition, the water vapor can be heated with energy from the raw gas (pyrolysis gas). This energy can be taken from the hot raw gas, which cools the raw gas. It can instead or additionally be generated by a sub-firing with raw gas. Another or another option is to expose the water vapor to energy to heat the flue gases. Accordingly, the energy for the fluidizing agent can be provided in-process by various means.

It is advantageous if the steam is used for the fluidization in the cracking reactor. It is thus possible first to use the superheated steam as a fluidizing agent and then to use the same steam in the cracking reactor / pyrolysis reactor for the cracking reactions.

The heat transfer medium is preferably formed by the ash from the combustion reactor. But it is also possible to use another heat transfer material or fluidized bed material. The heat transfer medium or the fluidized bed material may contain ash from the combustion reactor or consist exclusively or virtually exclusively of this ash.

Preferably, the ash from the combustion reactor, in particular the ash from the fluidized bed, and / or the pyrolysis coke from the pyrolysis reactor is used as a catalyst for the raw gas. As a result, the catalytic effect of the ash or the pyrolysis coke is used. As a catalyst for the raw gas, the ash and / or the pyrolysis coke can be used alone or with one or more further catalysts.

A further advantageous embodiment is characterized in that separated from the organic substances before pyrolysis, a fine fraction, in particular sieved. The fine fraction can also be separated in other ways. Preferably, the sieved or otherwise separated fine fraction is fed to the combustion reactor. The screening or other separation and / or the feeding of the fine fraction to the combustion reactor are particularly advantageous in the processing of Trockenstabilat ^® . Since the fine fraction of Trockenstabilats ^{® contains} an increased proportion of Inertien (ash) and pollutants, this is preferably screened off or otherwise separated. It is also preferably fed directly to the fluidized bed reactor for further treatment. Thus, the advantage can be achieved that the Schadstoffracht the input material (Trockenstabilat ^® ) via the fluidized bed reactor directly - ie without the detour through the shaft reactor and the cracking reactor - is led to the flue gas cleaning. The flue gas cleaning is carried out according to the valid environmental protection regulations, in Germany at the time according to the 17th Federal Immission Control Ordinance (BImSchV). It prevents the pollutant load from entering the environment. A further advantage is that the calorific value of the coarse fraction is increased compared to the original material, since the fine fraction of the Trockenstabilats ^{® contains} an increased proportion of Inertien (ash).

By cleaning or catalytic purification of the raw gas, a synthesis gas ("fuel gas") can be generated. The synthesis gas is preferably energetically utilized in a gas turbine or in another heat engine. It is advantageous if the exhaust gas from the energy recovery or the gas turbine or the other heat engine is supplied to the combustion reactor or fluidized bed reactor. The combustion reactor or fluidized bed reactor, in addition to this exhaust still air can be supplied. But it is also possible not to operate the combustion reactor or fluidized bed reactor with air, but only with the exhaust gas of the gas turbine or other heat engine. This is possible because the exhaust gas of the gas turbine or other heat engine still has a sufficient oxygen content, which may be about 17%. As a result, a particularly good energy recovery is possible.

According to a further advantageous development, the synthesis gas is first cooled and / or cleaned before it is used for the combustion chamber of the gas turbine or other heat engine. The cooling and / or cleaning is preferably carried out in a quench. Preferably, the wastewater is evaporated from the cooling and / or purification, preferably in a dryer. The remainder of the evaporation (the "thickened" residue) is preferably fed to the combustion reactor.

A further advantageous development is characterized in that a synthesis gas is generated by the purification or catalytic purification of the raw gas. Preferably, hydrogen is separated from the synthesis gas. The lean gas remaining in the hydrogen separation is preferably supplied to the combustion reactor. It can be used thermally there.

It is advantageous if the combustion reactor or fluidized bed reactor is operated in two stages. This is done in particular by the fact that less air is added at the lower end of the combustion reactor or fluidized-bed reactor than is required for a stoichiometric combustion. As a result, the ash, which is fed to the pyrolysis reactor or shaft reactor, still coke, which thus already in the upper part of the pyrolysis reactor (shaft reactor, degasser) has catalytic activity. Above the discharge of the ash from the combustion reactor or fluidized bed reactor, additional air is added in order to achieve complete combustion and to be able to deliver the exhaust gas - cleaned - into the environment.

A further advantageous development is characterized in that a zone of the pyrolysis reactor or shaft reactor is used as a cracking reactor. This may be done by carrying out the pyrolysis reactor and cracking reactor as a "pyrolysis cracking reactor" component so that one zone of the pyrolysis reactor is used as the catalyst (Figure 6). It can also be done in such a way that the cracking reactor is located above the pyrolysis reactor or shaft reactor or that the cracking reactor is in the upper region of the pyrolysis reactor or shaft reactor (FIG. 10).

A further advantageous development is characterized in that the raw gas purified in the cracking reactor is further purified in a further reactor with a catalyst bed (FIG. 7) or that the cracking reactor is designed as a reactor with a catalyst bed. The catalyst bed in the further reactor may consist of one or more metal compounds (permanent catalyst). After the gas has left the cracking reactor, it will supplied to the other reactor. The cracking reactor acts as a pre-catalyst in this case. The cracking reactor is then not necessary. It is also possible to dispense with the cracking reactor, so that the further reactor can act with the catalyst bed in this case as the actual cracking reactor for the catalytic purification of the raw gas produced by the pyrolysis.

It is particularly advantageous if the raw gas purified in the cracking reactor is further purified in a further reactor with a catalyst bed, that is to say if, in addition to the first further reactor with a catalyst bed, a second further catalyst with a catalyst bed is present. It is of particular advantage here if the first and second further reactors are activated alternately. The first and the second further reactor are thus operated so that they are alternately active. In this way, a further advantageous development is made possible, which consists in that the first and the second further reactor can be alternately regenerated, namely in each case when the other other reactor is activated. The regeneration is preferably carried out by hot exhaust gas from the combustion reactor or fluidized bed reactor. Even when using a first further reactor and a second further reactor can be dispensed with the cracking reactor. The first and the second further reactor then serve as actual cracking reactors for the catalytic purification of the raw gas produced by the pyrolysis.

A further advantageous development is characterized in that the catalyst is added together with the heat transfer medium or that the catalyst is effective together with the heat transfer medium. As already described, the pyrolysis coke from the pyrolysis reactor can be used as a catalyst for the raw gas. As a result, the catalytic effect of the pyrolysis coke produced in the pyrolysis reactor or shaft reactor is utilized. To achieve this, the cracking reactor is integrated into the solids flow from the pyrolysis reactor or shaft reactor into the combustion reactor or fluidized bed reactor. Taking into account the temperature level, however, a gas treatment, ie a catalytic purification of the raw gas, would be in that region of the pyrolysis reactor or shaft reactor desirable in which the ash from the combustion reactor or fluidized bed reactor is fed, since there the ash (heat transfer medium, fluidized bed material) has the highest temperature level.

To achieve this, the process is preferably carried out in such a way that the catalyst is added together with the heat transfer medium (ash) or that the catalyst is effective together with the heat transfer medium (ash). For example, the catalyst can be added at the top of the pyrolysis reactor or shaft reactor. This can be done together with the ashes. However, the catalyst can also be added otherwise. Further, the catalyst may be present in a cracking reactor to which the ash is fed.

It is possible to use a permanent catalyst, for example metal oxide. When using a permanent catalyst, a cycle results through the combustion reactor or fluidized bed reactor, wherein takes place in the furnace, the thermal cleaning of the catalyst. However, it is also possible to use a lost catalyst, for example coke or coal.

The inventive apparatus for pyrolysis and gasification of substance mixtures containing organic constituents, which is particularly suitable for performing the method according to the invention, comprises a pyrolysis reactor, preferably a shaft reactor, the organic substances or the substance mixture containing organic constituents, preferably Stabilat ^® and a heat transfer medium can be supplied, a combustion reactor, preferably a fluidized bed reactor, for burning the pyrolysis coke from the pyrolysis reactor or shaft reactor and for producing the heat transfer medium, wherein preferably the ash from the combustion reactor is used as the heat transfer medium, and a cracking reactor for cleaning or cracking produced by the pyrolysis crude gas or its condensable constituents, in which a catalyst is preferably provided.

According to the invention, a fluidized siphon is provided to which superheated steam as fluidizing agent can be supplied. The fluidized siphon may consist of a downcomer and a container with overflow. In this case, the heat transfer medium or the hot ash is collected in the downpipe. She trains a moving bed there and slips into the container. The container can be flown over a nozzle bottom located at the bottom of the nozzle with superheated steam, so that a fluidization of slipping from the downpipe ash is achieved and the ash can be removed from the overflow of the container. Due to the pressure loss of the moving bed in the downpipe, the desired sealing function is achieved, ie the sealing against gases (pyrolysis gases from the pyrolysis or the pyrolysis not allowed to enter the fluidized bed furnace, and flue gases from the fluidized bed furnace, which may not enter the pyrolysis). By the fluidization of the siphon, the promotion of the hot medium (heat transfer medium, hot ash) in a subsequent reactor (pyrolysis reactor / cracking reactor) is achieved. A small part of the water vapor can penetrate through the moving bed in the combustion reactor or fluidized bed furnace and thus act as a barrier gas.

Advantageous developments are described in the further subclaims.

The fluidized siphon comprises a downcomer.

In the downpipe, a moving bed is provided. The downpipe is designed such that a moving bed can be formed therein. Preferably, design parameters and / or operating parameters are influenced in such a way that a moving bed is formed in the downpipe.

The downpipe or the moving bed can be traversed by water vapor. The water vapor acts as a barrier gas. The design parameters and / or operating parameters are preferably influenced in such a way that water flows through the downpipe or the moving bed as sealing gas.

By the invention, a method and an apparatus are provided by which a pure gas can be produced from a fuel with a certain ash content and high volatile content, which is suitable both for use in gas turbine processes and internal combustion engines as well as for recycling, so that very high quality is. The objective is achieved that no technical oxygen must be used and that the pyrolysis gas does not come into contact with inert gases. The invention is particularly suitable for the processing of Trockenstabilat ^® . It can be assumed that the fine fraction of Trockenstabilats ^® on the one hand, above average levels of pollutants and on the other hand, a high inert content (about 50 wt .-%), the contribution of fine fraction to a high-quality gas so low and the negative impact on the effort of Pyrolysis gas cleaning are relatively high. The heat transfer medium is generated from the pyrolysis coke by way of combustion. The entire feed (organic substances, especially Trockenstabilat ^® ) passes through the pyrolysis with the fines and pollutes the gas cleaning. Preferably, the fine fraction is fed directly to the combustion; In the combustion reactor, the heat transfer medium is generated from this fine fraction and the pyrolysis coke. The volatile pollutants of the fine fraction can thereby be discharged in the combustion and separated in the flue gas cleaning. This prevents that pollutants from the fines get into the pyrolysis and gas purification can be unnecessarily complicated and expensive.

The resulting in the practice of the invention pyrolysis gas or synthesis gas can be used for material and energetic use, in particular for power generation, heat generation, for the production of methanol or for the production of hydrogen. It is possible to generate a hydrogen-rich gas. The invention can be used to generate electricity, in particular in a gas turbine. The gas turbine exhaust gas may be used as combustion and fluidizing air in the fluidized bed of the fluidized bed reactor. However, the system must then be operated under pressure or it is a fuel gas compressor provided. The furnace in the combustion reactor delivers fluid to the pyrolysis reactor. Due to the fluidized bed, the heat transfer medium, namely ash, is further generated in-process. If coke or pyrolysis coke is used as the catalyst material, this can also be generated within the process by means of stepped air supply in the fluidized bed. A process with substoichiometric combustion is possible. It is also possible to carry out the aftertreatment of the pyrolysis gases directly in the degasser (pyrolysis reactor); Degassing and cracking can therefore take place in a reactor.

Fig 1

eine Vorrichtung zur Durchführung eines Verfahrens zur Pyrolyse und Vergasung von Stoffgemischen, die organische Bestandteile enthalten, in einer schematischen Darstellung,

Fig. 2

die Vorrichtung gemäß Fig. 1, wobei der Schachtreaktor und der Crackreaktor als ein Bauteil "Pyrolyse-Crack-Reaktor" ausgeführt sind,

Fig. 3

eine weitere Ausführungsform, bei der der Katalysator zusammen mit dem Wärmeträgermedium zugegeben wird bzw. wirksam wird und

Fig. 4

einen fluidisierten Siphon, dem überhitzter Wasserdampf als Fluidisierungsmittel zuführbar ist, in einer schematischen Darstellung.

Embodiments of the invention are explained below with reference to the accompanying drawings in detail. In the drawing shows

Fig. 1

a device for carrying out a method for the pyrolysis and gasification of mixtures containing organic constituents, in a schematic representation,

Fig. 2

the device according to Fig. 1 wherein the shaft reactor and the cracking reactor are designed as a component "pyrolysis-cracking reactor",

Fig. 3

a further embodiment in which the catalyst is added or becomes effective together with the heat transfer medium and

Fig. 4

a fluidized siphon, the superheated steam can be supplied as a fluidizing agent, in a schematic representation.

In the Fig. 1 The basic configuration shown for carrying out the basic process consists of a shaft reactor 1, a fluidized bed reactor 2 and a cracking reactor 3. The shaft reactor 1, the organic matter, preferably Trockenstabilat ^® 4, and the heat transfer medium, preferably ash 5, from fed to the fluidized bed reactor 2. The dry stabilizer 4 introduced into the shaft reactor 1 is mixed there with the hot ash 5 from the fluidized-bed reactor 2. The dry stabilate heats up and degasifies (pyrolyzed). The result is a gas, namely the raw gas 6, and a solid 7, namely pyrolysis and ash. The crude gas 6 leaves the shaft reactor 1 at the top, the solid 7 leaves the shaft reactor 1 at the bottom. Crude gas 6 and solid 7 are fed to the cracking reactor 3. Since the solid 7, namely the pyrolysis coke contained therein, acts as a catalyst for the gas purification, the crude gas 6 is passed in the cracking reactor 3 through the hot solid. Further, water vapor 8 is added here. As a result, a catalytically purified gas 9 (synthesis gas, fuel gas) is obtained. The solid 10 from the cracking reactor 3 (pyrolysis coke and ash) is introduced into the fluidized bed reactor 2 and burned there with air 11. The exhaust gas 12 from the fluidized bed of the fluidized bed reactor 2 is cleaned. From the fluidized bed reactor 2 also not required ash 13 can be deducted.

At the in Fig. 2 In the embodiment shown, the shaft reactor and the cracking reactor are designed as one component, namely as a pyrolysis-cracking reactor 30. Here, one zone, namely the lower zone, of the pyrolysis reactor 1 is used as the catalyst.

In the in the FIGS. 1 and 2 In the embodiments shown, the catalytic effect of the pyrolysis coke produced in the shaft reactor 1 is utilized. In these embodiments, the cracking reactor 3 is integrated into the solids flow from the shaft reactor 1 into the fluidized bed reactor 2. In consideration of the temperature level, however, a gas treatment in that area of the shaft reactor 1 would be desirable, in which the ash 5 is supplied from the fluidized bed reactor 2, since there the solid (the ash) has the highest temperature level.

To realize this, the process can be after Fig. 3 be provided. Here, a catalyst 40 is added in the upper region of the shaft reactor 1. The shaft reactor and the cracking reactor are also designed here as one component, namely as pyrolysis cracking reactor 30 '. However, the addition of the catalyst 40 in the upper region of the shaft reactor 1 does not necessarily have to take place with the ash 5 from the fluidized-bed reactor 2. The catalyst can also be added in other ways. Furthermore, the catalyst can be present in the upper region of the shaft reactor 1, that is to say in the region of the pyrolysis cracking reactor 30 'designated 41. In the embodiment of Fig. 10, a permanent catalyst such as metal oxide may be used. However, a lost catalyst such as coke or coal may also be used. When using a permanent catalyst, a cycle through the fluidized bed reactor 2 results, wherein takes place in the furnace of the fluidized bed reactor 2, the thermal cleaning of the catalyst. The cracking reactor is automatically integrated into the shaft reactor 1 so that it becomes the pyrolysis-cracking reactor 30 '.

The FIG. 4 shows one in the embodiments according to FIGS. 1 to 3 Applicable plant part, can be promoted by the hot ash or other fluidized bed material from the fluidized bed reactor or fluidized bed furnace 2 to the pyrolysis reactor or shaft reactor 1 and the pyrolysis cracking reactor 30 and 30 '. In the fluidized bed furnace 2 is a fluidized bed 41 ', which consists of fluidized bed material, namely hot ash. The bottom of the fluidized bed furnace 2 is formed as a nozzle bottom 42, through which the fluidized bed furnace 2 fluidizing air 43 is supplied.

The hot ash from the fluidized bed 41 'is fed to a cracking reactor / pyrolysis reactor / shaft reactor / pyrolysis cracking reactor 1, 3, 30, 31, 30', 41 ', which in the Fig. 4 are not shown and lie in the direction of material flow behind the arrow 44.

The Indian Fig. 4 illustrated fluidized siphon 45 includes a downpipe 46, which may also be formed as a chute, and a container 47 with overflow. The hot ash from the fluidized bed 41 'passes through the in the fluidized bed furnace second trained ash spill 48 into the downpipe 46, where it is collected. This hot ash forms in the downpipe 46 from a moving bed and slips into the container 47. The bottom of the container 47 is formed as a nozzle bottom 49 through which the container 47 superheated steam 50 is supplied.

With the aid of the superheated steam 50, the container 47 is flowed over the bottom of the nozzle 49 located on the bottom of the container, so that a fluidization of the ash slipping out of the downpipe 46 is achieved and the ash from the overflow of the container 47 can be withdrawn into the further downpipe 51. It is guided by the further downpipe 51 in the direction of the arrow 44 to the shaft reactor 1 / pyrolysis-cracking reactor 30 / pyrolysis-cracking reactor 30 '.

Due to the pressure loss of the fixed bed in the downpipe 46, the desired sealing function is achieved. The fluidized siphon according to Fig. 4 performs the functions of conveying a solid and sealing against gases. By the fluidization of the siphon, the promotion of the hot medium in a subsequent reactor 1, 30, 30 'is achieved.

The downcomer 46, in conjunction with the fluidized siphon 45, permits separation of oxidizing atmosphere in the combustion reactor or fluidized bed furnace and reducing atmosphere in the cracking reactor and in the pyrolysis reactor. A defined, very small vapor stream penetrates through the moving bed in the downpipe 46 in the combustion reactor or fluidized bed furnace and thus acts as a sealing gas. This sealing steam flow can be adjusted in a targeted manner by permanently setting a pressure drop across the moving bed in the downpipe 46. This pressure drop can be influenced by the height of the moving bed (design parameters) and by the steam pre-pressure and the negative pressure in the combustion reactor or fluidized bed furnace (operating parameters). Influencing by other and / or further design parameters and / or operating parameters is possible. The main stream of water vapor passes either together with the ash or in addition via a bypass in the cracking reactor and thus blocks the siphon against raw gas from the cracking reactor.

In the method according to the German patent application 100 33 453 , 9 can be used in the pyrolysis reactor for carrying out the desired cracking reactions superheated steam with 1.0 to 1.5 bar pre-pressure and around 800 ° C to 850 ° C used. Thus, it is possible to first use the superheated steam 50 as a fluidizing agent and then use the same steam in the cracking reactor / pyrolysis reactor 1, 3, 30, 31, 30 ', 41 for the cracking reactions. The amount of superheated steam from the fluidization of the siphon is about 0.07 to 0.12 kg steam per kg Trockenstabilat ^® much lower than the total required amount of steam of about 0.3 kg steam per kg Trockenstabilat ^® and therefore in no way harmful to the process but even beneficial.

The energy for the provision of the steam at 1.5 bar and 800 to 850 ° C can be obtained from the cooling of the flue gases from the combustion of the pyrolysis coke. Thus, the energy for providing the fluidizing agent can be generated or used in-process.

Surprisingly, it has been found that the superheated steam added as fluidizing agent does not lead to a reduction in the calorific value of the synthesis gas mixed with it in the further course of the process. In connection with the method according to the German patent application 100 33 453.9 This particular advantage is achievable because of the supply of superheated steam longer-chain hydrocarbons are cracked in the pyrolysis gas and thus the calorific value of the synthesis gas is increased. The desired cracking reactions are thus a peculiarity that makes it particularly useful to use superheated steam as a fluidizing agent, without any deterioration of the synthesis gas occurs and without the water vapor obtained during the cooling of the synthesis gas as additional condensate.

Claims (23)

1. A method for the pyrolysis and gasification of substance mixtures containing organic constituents,
   wherein the organic substances (4) or the substance mixture containing organic constituents are brought into contact with a heat transfer medium in a pyrolysis reactor (1) and are pyrolised;
   wherein the pyrolysis coke (7) created by the pyrolysis is combusted in a combustion reactor (2) with an air supply (11);
   wherein the condensable constituents of the raw gas (6) produced by pyrolysis are cracked in a crack reactor (3);
   and wherein the heat transfer medium is conveyed as a fluidising agent by means of overheated steam (50) in a fluidised syphon,
   characterised in that
   the fluidised syphon includes a down-pipe (46) and a container (47) with overflow, with the base of the container (47) being formed as a nozzle base (49) through which overheated steam (50) is supplied to the container (47);
   in that the main flow of the steam (50) enters into the crack reactor (3) either together with the ash or additionally via a bypass; and in that a defined barrier vapour flow passes through the moving bed in the down-pipe (46).
2. A method in accordance with claim 1, characterised in that the steam (50) is heated with energy from the combustion of the pyrolysis coke and/or with energy from the raw gas (6).
3. A method in accordance with claim 1 or claim 2, characterised in that the steam (50) is heated with energy from the flue gases.
4. A method in accordance with one of the preceding claims, characterised in that the steam (50) is used for the fluidisation in the crack reactor (1, 3, 30, 31, 30', 41).
5. A method in accordance with one of the preceding claims, characterised in that the heat transfer medium comprises the ash (5) of the combustion reactor (2).
6. A method in accordance with one of the preceding claims, characterised in that a catalyst is provided in the crack reactor (3).
7. A method in accordance with one of the preceding claims, characterised in that the cracking is carried out while adding water vapour (8).
8. A method in accordance with one of the preceding claims, characterised in that the pyrolysis coke (7) from the pyrolysis reactor (1) and/or the ash from the combustion reactor (2) is used as the catalyst for the raw gas (6).
9. A method in accordance with one of the preceding claims, characterised in that a fine fraction is separated from the organic substances (4) before pyrolysis.
10. A method in accordance with one of the preceding claims, characterised in that a synthesis gas is produced by the purification of the raw gas.
11. A method in accordance with claim 10, characterised in that hydrogen is separated from the synthesis gas.
12. A method in accordance with one of the preceding claims, characterised in that a zone of the pyrolysis reactor (1) is used as the crack reactor.
13. A method in accordance with one of the preceding claims, characterised in that the catalyst is added or becomes active together with the heat transfer medium.
14. A method in accordance with claim 13, characterised in that the catalyst (40) is added to the heat transfer medium (5).
15. An apparatus for the pyrolysis and gasification of substance mixtures containing organic constituents, in particular for carrying out the method in accordance with one of the claims 1 to 14, comprising
    a pyrolysis reactor (1), preferably a shaft reactor, to which the organic substances (4) or the substance mixture containing organic constituents and a heat transfer medium (5) can be supplied;
    a combustion reactor (2), preferably a fluidized bed reactor, for combusting the pyrolysis coke (7) from the pyrolysis reactor (1) and for generating the heat transfer medium (5) for the pyrolysis reactor (1);
    a crack reactor (3) for cracking the condensable constituents of the raw gas (6) generated by the pyrolysis;
    and a fluidised syphon (45) to which overheated water vapour (50) can be supplied as the fluidising agent,
    characterised in that
    the fluidised syphon includes a down-pipe (46) and a container (47) with overflow:

    a fluidised bed can be formed in the down-pipe (46);

    the hot ash or the other fluidised bed material from the down-pipe (46) can be supplied to the container (47);

    the container (47) has an overflow from which the hot ash or the other fluidised bed material can be drawn off into a further down-pipe (51);

    and in that the base of the container (47) is formed as a nozzle base (49) through which overheated water vapour (50) is supplied to the container (47).
16. An apparatus in accordance with claim 15, characterised in that a moving bed is provided or can be formed in the down-pipe (46).
17. An apparatus in accordance with claim 15 or claim 16, characterised in that a catalyst is provided in the crack reactor (3).
18. An apparatus in accordance with one of the claims 15 to 17, characterised by a quench for cooling and/or purifying the synthesis gas (9).
19. An apparatus in accordance with claim 18, characterised by a dryer for cooling and/or purifying the waste water from the quench.
20. An apparatus in accordance with one of the claims 15 to 19, characterised by a hydrogen separation for separating hydrogen from the synthesis gas from the crack reactor (3).
21. An apparatus in accordance with one of the claims 15 to 20, characterised in that the pyrolysis reactor (1) or the shaft reactor and the crack reactor (3) are configured as one element, preferably as a pyrolysis crack reactor (30, 30').
22. An apparatus in accordance with one of the claims 15 to 21, characterised by a further reactor having a catalyst bed.
23. An apparatus in accordance with claim 22, characterised by a second further reactor having a catalyst bed.

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