EP3969545A1

EP3969545A1 - Method for recovering at least one recyclable material contained in a biomass

Info

Publication number: EP3969545A1
Application number: EP20718519.0A
Authority: EP
Inventors: Bernd MICKISCH; Peter ILLECKER; Udo PROKSCH; Andreas Hackl
Original assignee: Next Generation Elements GmbH
Current assignee: Next Generation Elements GmbH
Priority date: 2019-03-06
Filing date: 2020-03-04
Publication date: 2022-03-23
Also published as: WO2020176917A1

Abstract

The invention relates to a method for thermochemically treating biomass (5) and recovering a recyclable material contained therein. The biomass (5) is supplied to a pyrolysis reactor (2) and broken down therein to give pyrolytic coke and pyrolysis gas, wherein the pyrolytic coke is further conveyed to a coke gasifier (3) and broken down therein to give a solid residue product and a gasifier gas. The pyrolysis gas and the gasifier gas are supplied to a combustion apparatus (4) and burned therein to give flue gas. At least a part of the flue gas is supplied to the coke gasifier (3) from the combustion apparatus (4).

Description

METHOD OF RECOVERY AT LEAST ONE IN A BIOMASS

CONTAINED RECYCLING SUBSTANCES

The invention relates to a method for thermo-chemi see treatment of biomass, in particular organic waste products, and the recovery of at least one valuable material contained in the biomass.

DE 10 2008 028 241 A1 describes a device for thermo-chemi see Elmwand development of biomass in a fuel gas. The device consists of a screw reactor and another reactor. In the screw reactor, the biomass is dried and pyrolysed with the exclusion of air, the pyrolysis coke produced in the process, the pyrolysis gas and water vapor being fed together to the further reactor, which is filled with the formation of a pyrolysis coke bed. In the further reactor, partial oxidation takes place through the sub-stoichiometric addition of a gasification agent, in particular air. In the process, the long-chain tar molecules are at least partially split up. The residues are withdrawn from the further reactor at the bottom by means of a withdrawal device. In order to prevent clogging of inlet openings for the gasification agent and / or outlet openings for the fuel gas in the region of the reactor wall, a large number of interior extensions extending at least partially in the direction of gravity are provided. The resulting fuel gas is fed to a gas filter and a gas cooler via its own outlet openings. The cleaned fuel gas flowing out of the outlet of the gas cooler is then fed to a gas engine, for example. The electrical energy generated in the gas engine can be fed into the supply network, whereby the heat generated can also be used to heat the aforementioned screw reactor.

The object of the present invention was to provide a method by means of which a user is able to treat a biomass in such a way that at least one valuable material contained therein can be recovered and thus a residue product is created, which in particular as Fertilizers can be used. Furthermore, the burning of biomass as a classic disposal route is also to be avoided. This object is achieved by a method according to the claims.

The method is used to see thermo-chemical treatment of biomass, in particular of organic waste products such as sewage sludge, slaughterhouse waste, animal meal, excrement, and the recovery of at least one valuable material contained in the biomass. At least the following steps are carried out in a treatment system:

Providing at least one pyrolysis reactor,

Providing at least one coke gasifier,

Providing at least one burning device,

Provision of the biomass to be treated,

Feeding the provided biomass to be treated into the pyrolysis reactor,

Pyrolysis of the biomass in the pyrolysis reactor and thermal decomposition of the biomass in pyrolysis coke and pyrolysis gas,

spatially separated removal of the pyrolysis coke and removal of the pyrolysis gas from the pyrolysis reactor,

Further conveying and feeding of the pyrolysis coke into the coke gasifier,

Gasification of the pyrolysis coke in the coke gasifier, the pyrolysis coke being further decomposed into a solid, in particular pourable, residue product and into a gasifier gas, and the residue product contains at least one valuable substance,

spatially separated removal of the residue product and removal of the gasifier gas from the coke gasifier,

Feeding the pyrolysis gas derived from the pyrolysis reactor into the combustion device, the pyrolysis gas being burned in the combustion device to form a flue gas, and discharging the flue gas from the combustion device,

Feeding the derived from the coke gasifier gasifier in the Brennvor direction, wherein the gasifier gas burns ver in the combustion device to form the flue gas and is also derived from this, and / or feeding the derived from the coke gasifier gasifier into an internal combustion engine, and

Feeding at least a portion of the flue gas diverted from the combustion device into the coke gasifier.

With these process steps selected here, a controlled process sequence is created in which a residue product with the at least one contained therein Recyclable material is obtained. The treatment takes place in an at least two-stage process, this being done by feeding the biomass to be treated into the pyrolysis reactor and the further post-treatment of the pyrolysis coke produced there from the coke gasifier by means of thermo-chemical decomposition.

Depending on the selected biomass, in particular organic waste products, recovery of the valuable material contained therein, in particular phosphorus or phosphorus compounds, phosphates, potassium, calcium, magnesium or the like, is achieved. Furthermore, due to the thermo-chemical decomposition, the gas produced in each case is burned for a combustion process in a separate burner device. By means of the combustion process, pollutants or additives previously contained in the biomass can be separated or disposed of and filtered out. In addition, a sufficient amount of heat energy is provided, which can be used within the treatment plant for a wide variety of purposes. At least a portion of the flue gas produced in the combustion device is fed to the coke gasifier to its operation for further thermal treatment of the pyrolysis coke. This means that the oxygen still contained in the flue gas and other possible gas components are used in the final treatment of the pyrolysis coke in the coke gasifier. The residue product produced in this way from the biomass contains after the treatment process the at least one valuable substance to be recovered, with the thermochemical decomposition also breaking down and / or eliminating problematic substances otherwise contained therein.

Furthermore, a procedure is advantageous in which the pyrolysis gas formed in the pyrolysis reactor is collected in a collecting container immediately after it has been discharged from the pyrolysis reactor and before being passed on to the burner, and dust-like components still in the pyrolysis gas are deposited in the collecting container . In this way, at least a large part of the suspended matter still contained in the pyrolysis gas can be separated off before the combustion process. Furthermore, the cleaning effort of the gas line to the combustion device can also be reduced. In addition, an even better and more intensive combustion of the pyrolysis gas in the combustion device is achieved in this way. Another advantageous procedure is characterized in that the pyrolysis gas and / or the gasifier gas are or will be fed to the combustion device at a temperature of at least 400 ° C. Through the selected minimum temperature, unwanted condensation of gas components in the gas lines up to the combustion device can be avoided.

An alternative procedure provides that heat energy is withdrawn from the carburetor gas before it is fed into the combustion device and / or before it is fed into the internal combustion engine and is thereby cooled to a temperature value that comes from a temperature value range whose lower limit is 100 ° C., in particular 150 ° C., and its upper limit is 400 ° C., in particular 250 ° C. A certain amount of thermal energy can be withdrawn from the carburetor gas before it is fed into the combustion device and / or the combustion engine, which can be used by means of the heat exchanger on a further system component provided for this purpose.

A variant of the method is also advantageous in which the pyrolysis gas and the gasifier gas are fed to the combustion device separately from one another. By supplying the pyrolysis gas and the carburetor gas separately to the combustion device, even more complete and better combustion can be achieved, whereby the heat extraction can also be increased accordingly.

Another procedure is characterized in that the pyrolysis coke discharged from the pyrolysis reactor is conveyed into an intermediate container before being fed into the coke gasifier. In this way, independent operation of the pyrolysis reactor and the coke gasifier can be achieved within certain limits. In addition, the amount withdrawn from the intermediate container and thus the degree of filling of the coke gasifier can also be adjusted for an optimal process sequence.

Furthermore, a procedure is advantageous in which the pyrolysis coke is conveyed from the intermediate container to the coke gasifier by means of a screw conveyor and a rotary valve located downstream of the screw conveyor. This enables a controlled and safe filling of the coke gasifier to be achieved. A variant of the method is also advantageous in which the coke gasifier comprises a screw conveyor and the pyrolysis coke conveyed further from the pyrolysis reactor is fed to the coke gasifier by means of a connecting line directly and shut off from the external ambient conditions. The treatment of the pyrolysis coke in the coke gasifier can thus be continued without a high loss of heat. In addition, long transport routes and intermediate storage can be saved.

Another advantageous procedure is characterized in that the flue gas diverted from the combustion device, in particular before being fed into the coke gasifier, is passed through a heat exchanger and thermal energy is withdrawn from the flue gas. In this way, the thermal energy contained in the flue gas can be used and the flue gas can be cooled from 1,000 ° C to around 200 ° C, for example. The Wärmetau shear can supply a hot water system, this thermal energy for dewatering and / or drying of the biomass can be supplied to the pyrolysis reactor before it is supplied.

A variant of the method is also advantageous in which the flue gas discharged from the combustion device, in particular before being fed into the coke gasifier, is passed through a filter device and is filtered in the process. In this way, suspended matter, pollutants or the like contained in the flue gas can be filtered out in order to be able to feed a cleaned flue gas to the coke gasifier for renewed combustion.

Another approach is distinguished when oxygen, in particular in the form of ambient air, is added to the flue gas before it is fed into the coke gasifier. In this way, the intensity of the combustion of the flue gas in the coke gasifier can be precisely matched to the respective treatment process. The higher the amount of oxygen supplied to the flue gas, the more the gasification temperature or the combustion temperature can be increased.

A variant of the method is also advantageous in which the flue gas, which may have been enriched with oxygen, is fed to the coke gasifier at a pressure which is higher than the ambient atmospheric pressure. In this way, a directed flow and a better and more uniform supply of the pyrolysis coke to be treated can be achieved within the coke gasifier, at least with the flue gas. Furthermore, a procedure is advantageous in which the gasifier gas formed in the coke gasifier is fed from this via the connecting line to the pyrolysis reactor, in particular is fed at a pressure that is higher than the ambient atmospheric pressure. A countercurrent movement with respect to the conveying direction of the pyrolysis coke in the connecting line can thus be achieved. Furthermore, a filter effect and, associated with this, a cleaning effect of the carburetor gas can be achieved within the connection line.

Another approach is characterized when the pyrolysis gas and the gasifier gas fed to the pyrolysis reactor are fed together to the combustion device. A mixture of the two gases can thus be formed upstream of the combustion device. In addition, better mixing can be achieved in this way.

Furthermore, a procedure is advantageous in which the pyrolysis coke is gasified in the coke gasifier with a temperature value that comes from a temperature value range, the lower limit of which is 400 ° C., in particular 500 ° C., and the upper limit of which is 1,000 ° C., in particular 900 ° C. , is. By choosing the level of the temperature value, the subsequent consistency of the residue product produced in the coke gasifier with the at least one material contained therein can be determined.

Another advantageous procedure is characterized in that the temperature value for the gasification of the pyrolysis coke in the coke gasifier is set by means of the proportion of added oxygen, in particular of mixed ambient air, to the flue gas. The controlled addition of oxygen to the flue gas enables targeted control of the gasification temperature in the coke gasifier. This can counteract sintering or fusion of the residue product, which can be the case if the temperatures chosen are too high.

A variant of the method is also advantageous in which at least a proportion of the biomass to be treated is dewatered to a moisture value by means of a dewatering device before being fed into the pyrolysis reactor, which comes from a moisture value range, the lower limit of which is 70% by weight, in particular 80% by weight, and its upper limit is 95% by weight, in particular 90% by weight. Depending on the moisture present, a certain amount of pre-drying of the biomass and a reduction in the water content can be achieved. Another procedure is characterized by the fact that at least a proportion of the biomass to be treated is dried by means of a drying device to a moisture value that comes from a moisture value range, the lower limit of which is 3% by weight, before being fed into the pyrolysis reactor. in particular 5% by weight, and its upper limit is 20% by weight, in particular 10% by weight. This allows the moisture value to be reduced even further, which means that better and more trouble-free operation can be achieved in the subsequent pyrolysis reactor.

It can also be advantageous if the thermal energy withdrawn from the flue gas in the heat exchanger is fed to the drying device. In this way, at least a large part of the heat energy contained in the flue gas can also be used when the treatment plant is in operation, without additional heat energy having to be supplied or made available.

Another advantageous procedure is characterized in that the mass flow of the biomass fed to the pyrolysis reactor is determined. A safer and more uniform operation of the treatment system can thus be achieved.

A variant of the method is also advantageous in which the biomass to be treated is fed to the pyrolysis reactor in a gas-tight manner by means of a lock system. In this way, unwanted access of oxygen into the interior of the pyrolysis reactor and thus in its treatment zone when the pyrolysis reactor is being filled can be prevented.

For a better understanding of the invention, it is explained in more detail with reference to the following figures.

It shows in a greatly simplified, schematic representation:

1 shows a system diagram of a treatment system with indicated system components;

Fig. 2 shows a further system scheme with a combined treatment unit of py rolysis reactor and coke gasifier

3 shows a further possible system scheme of the treatment system according to FIG. 1, with an additional heat exchanger. At the outset, it should be noted that in the differently described embodiments, the same parts are provided with the same reference numerals or the same component designations, and the disclosures contained in the entire description can be transferred accordingly to the same parts with the same reference numerals or the same component names. The position details chosen in the description, such as above, below, side, etc., refer to the figure immediately described and shown and these position details are to be transferred accordingly to the new position in the event of a change in position.

The term “in particular” is understood below to mean that it can be a possible more specific design or more detailed specification of an object or a method step, but does not necessarily have to represent a mandatory, preferred embodiment of the same or a mandatory procedure.

In FIG. 1, a system diagram of a treatment system 1 is shown in a simplified and highly stylized manner, which comprises at least one pyrolysis reactor 2, at least one coke gasifier 3 and at least one combustion device 4. The treatment system 1 is basically intended to treat biomass 5 in a thermo-chemical treatment process or thermo-chemical treatment process, the recovery of at least one valuable material contained in the biomass 5 being aimed at as one of the goals. The valuable material can e.g. Phosphorus (P) or a phosphorus compound such as e.g. P2O5, potassium, calcium, magnesium or the like. As so-called biomass 5 here in particular organic waste products such as sewage sludge, slaughterhouse waste, animal meal, excrement or the like are understood.

Depending on the type and composition of the biomass 5, it has so far been disposed of or processed in a wide variety of ways. A first possibility is thermal recovery through incineration in waste incineration plants, a cement works or similar plants. Another possibility, especially in the case of sewage sludge, is agricultural spreading in the fields. However, all of the pollutants, microplastics and the like contained in the sewage sludge are distributed across the fields and thus end up in the groundwater. Finally, composting or soil can also take place. The plant components described above, namely the pyrolysis reactor 2, the coke gasifier 3 and the combustion device 4, form the basic components of the treatment plant 1 for the intended recovery of at least one valuable material contained in the biomass, where further plant components are possible and represent a supplement can.

At least a proportion of the biomass 5, but in particular the entire amount of biomass 5 to be treated, can be dewatered to a moisture value in a dewatering device 6 before being fed into the pyrolysis reactor 2, which comes from a moisture value range of which lower limit 70% by weight, in particular 80% by weight, and its upper limit is 95% by weight, in particular 90% by weight, based on the total mass of the biomass 5.

Independently of this dehydration step or in addition to this dehydration step, at least a proportion of the biomass 5 to be treated, but in particular the entire amount of the biomass 5 to be treated, can be dried in a drying device 7 in a drying device 7 before being fed into the pyrolysis reactor 2 originates from a moisture range, the lower limit of which is 3% by weight, in particular 5% by weight, and the upper limit of which is 20% by weight, in particular 10% by weight. Preferably, however, the entire amount of biomass 5 to be treated is subjected to predrying. If both the dewatering device 6 and the drying device 7 are seen, they can form a drying system.

The biomass 5 to be treated can be fed to the pyrolysis reactor 2 with the previously described moisture reduction and / or without the previously described moisture reduction. It is still possible to determine the mass flow of the biomass 5 fed to the pyrolysis reactor 2 and, if necessary, to store or store it in a control device 8. The control device 8 also serves to monitor the entire process of biomass treatment from its delivery to the end of the entire treatment process and to control all system parts or system components according to predetermined process steps. The respective communication connections between the control device 8 and the individual system parts or system components are indicated in dashed lines. The feeding of the biomass 5 into the pyrolysis reactor 2 can take place in a preferably gas-tight manner by means of a lock system 9, such as a vertical rotary lock. If the biomass 5 has been fed to the pyrolysis reactor 2, a thermo-chemical conversion of the biomass 5 takes place in it, which can be referred to as a pyrolysis process. Here there is thermal decomposition of the biomass 5 in pyrolysis coke and pyrolysis gas, each with a wide variety of components. The pyrolysis coke is predominantly a solid fraction, which can also be referred to as carbonizate. The pyrolysis reactor 2 can for example be designed as a screw reactor in which the thermal decomposition of the biomass 5 takes place at a temperature in a temperature range between 400 ° C, in particular 450 ° C, and 600 ° C, in particular 550 ° C. This process takes place under reduced oxygen conditions with a residence time between 20 and 30 minutes. There can be a low oxygen concentration of less than 5% in the pyrolysis reactor 2.

The pyrolysis gas produced is mostly an oil / gas mixture, possibly with dust-like fractions.

After the biomass 5 has been treated in the pyrolysis reactor 2, the pyrolysis coke produced in the process and the pyrolysis gas are discharged or diverted from the pyrolysis reactor 2 in a spatially separated manner. The further treatment of the pyrolysis coke with the possible process steps is described below.

The pyrolysis coke formed in the pyrolysis reactor 2 from the biomass 5 is now in principle Lich to carry out a further treatment step in the coke gasifier 3 weitergeför changed. This can be done in a direct way. However, it would still be possible for the pyrolysis coke discharged from the pyrolysis reactor 2 to be conveyed into an intermediate container 10 before being fed into the coke gasifier 3 and temporarily stored there. The removal from the intermediate container 10 or the step of further conveying the pyrolysis coke from the intermediate container 10 to the coke gasifier 3 can e.g. take place by means of a screw conveyor and a rotary valve arranged after the screw conveyor.

If the biomass 5 treated to form pyrolysis coke in the first treatment step is in the coke gasifier 3, the pyrolysis coke is further gasified in a subsequent treatment step. The pyrolysis coke is decomposed into a predominantly solid residue product, in particular a free-flowing residue product, and into a gasifier. The mostly solid residue product contains the at least one valuable material on which the recovery is directed. The residue product is spatially separated from the coke gasifier 3 discharged from the gasifier gas, whereby the residue product can be collected in an unspecified container. The gasifier gas is thus derived specifically from the coke gasifier 3.

The pyrolysis gas produced in the pyrolysis reactor 2 from the biomass 5 is in turn passed into the combustion device 4, the pyrolysis gas being burned in the combustion device 4 with the formation of a flue gas. The resulting or formed flue gas is diverted from the combustion device 4.

It can also be passed from the coke gasifier 3 gasifier gas in the Brennvorrich device 4, wherein the gasifier gas is burned in the combustion device 4 to form the flue gas. The resulting or formed flue gas is also discharged from the combustion device 4. If both gases, namely the pyrolysis gas and the carburetor gas, are fed to the combustion device 4, they can be fed to the combustion device 4 spatially separated from one another and burned therein. Independently of this, however, both gases could also be fed together to the combustion device 4, as is indicated by an arrow shown in dash-dotted lines.

However, it would also be possible not to feed the carburetor gas to the combustion device 4, but instead to feed it exclusively to an internal combustion engine 11. Furthermore and independently of this, only a partial flow or a partial amount of the carburetor gas could be taken from the total flow, with a first partial flow or a partial amount of the carburetor gas being fed to the combustion device 4 and a further partial flow or a partial amount of the carburetor gas being fed to the internal combustion engine 11 . That partial stream or that partial amount of the gasifier gas which is fed to the combustion device 4 can either be fed separately from the pyrolysis gas to the combustion device 4 or mixed with the pyrolysis gas upstream of the combustion device 4, as has already been mentioned above.

Both partial flows together form the total flow of the carburetor gas. The combustion gas produced during the operation of the internal combustion engine 11 could also be mixed with the flue gas fed to the coke gasifier 3. However, it would also be possible not to feed a portion of the flue gas diverted from the combustion device 4 to the coke gasifier 3, but rather either before it is passed through a filter device 13 and / or a heat exchanger 14 or after passing through the filter device 13 and / or the heat exchanger 14 for another thermal use. This can be for a wide variety of purposes, such as another combustion process, in a drying system, as a recirculation gas or the like.

For this purpose, possible examples for the diversion of at least one further partial quantity or at least one further partial extraction of the flue gas from a flue gas line between the combustion device 4 and the coke gasifier 3 are indicated in dashed lines.

A further possible partial amount of the flue gas can e.g. take place before the heat exchanger 14 and / or after the heat exchanger 14. In the present embodiment, a portion of the flue gas is removed after the heat exchanger 14 and before the filter device 13 and fed to the combustion device 4 again. The feed line can e.g. take place before entry into the combustion device 4 in such a way that the partial amount of smoke gas is mixed with the pyrolysis gas and the two gases are fed together to the combustion device 4.

Additionally or independently of this, however, a further partial amount of the flue gas could also be removed after passing through the filter device 13. This further possible part of the flue gas can be used in the drying device 7 as heat energy carriers during the drying process. The previously described removal of at least a partial amount from the total flow of the total amount of flue gas can take place, but does not have to be. It would also be possible to feed the entire flow of flue gas, that is, the entire amount of flue gas to the coke gasifier 3. If at least a partial amount or several partial amounts are withdrawn, this exemplary embodiment shown can be a maximum of four partial amounts and their withdrawal from the total amount or the total flow. A first partial amount must always be fed to the coke gasifier 3 in any case. The other subsets can be those which are supplied to the drying device 7, the combustion device 4 and the chimney 15. It should be mentioned that only one of the subsets described above can be withdrawn, or two subsets or even three subsets can be withdrawn.

But it could also be a portion of the flue gas, in particular only after passing through the filter device 13 and / or the heat exchanger 14, via a chimney 15 to the Ambient air are released. The chimney 15 is schematically seen in the flow direction of the flue gas to the coke gasifier 3, a admixing device 16 for additional oxygen arranged upstream of the flue gas. The purpose of the admixing device 16 is explained in more detail below.

The pyrolysis gas formed or arising in the pyrolysis reactor 2 can be collected in a collecting container 12 immediately after it has been discharged from the pyrolysis reactor 2 and before it is passed on to the combustion device 4. This creates the possibility, while it is in the collecting container 12, that dust-like fractions that are still in the pyrolysis gas can be deposited in the collecting container 12. The pyrolysis gas consists predominantly of approx. 15-20% permanent gases and in addition each 100% of approx. 85-80% condensable components. The permanent gases can in particular be CO, CO2, H2, N2, H2S, CH4. The condensable components can primarily be H2O, organic compounds such as acetic acid, butyric acid, aromatic hydrocarbons, diverse hetero compounds or compounds of higher molecular weight (oils) or the like.

It is advantageous if the pyrolysis gas and / or the carburetor gas are or will be fed to the combustion device 4 at a temperature of at least 400 ° C. If the temperature in the supply lines is lower, this can lead to unwanted condensation in the line or in the lines.

The gas diverted from the combustion device 4 is generally referred to as “flue gas”.

For example, the combustion product formed or arising during the joint combustion is referred to below as "flue gas" when both the pyrolysis gas and the gasifier gas are fed into the Brennvor direction 4.

The combustion product "flue gas" still has a residual proportion of oxygen (O2), whereby the oxygen content in the flue gas can be around 5%. The flue gas is diverted from the combustion device 4, at least a portion of which is subsequently fed to the coke gasifier 3. It can thus be advantageous if the flue gas derived from the Brennvor device 4 is filtered in the filter device 13, in particular before being fed into the coke gasifier 3. In order to achieve an additional enrichment of at least that portion of the derived flue gas with oxygen, which the coke gasifier is fed, this oxygen, in particular in the form of ambient air, can be added or buried before the flue gas is fed into the coke gasifier 3. This can be done by means of the admixing device 16. The operating temperature of the coke gasifier 3 can subsequently be set within certain limits through the amount or proportion of added oxygen to the flue gas, and thus the temperature of the gasification of the py rolyse coke in the coke gasifier 3 can be determined. The pyrolysis coke can be gasified in the Koksverga ser 3 with a temperature value which comes from a temperature value range whose lower limit is 400 ° C, in particular 500 ° C, and whose upper limit is 1,000 ° C, in particular 900 ° C.

The flue gas discharged from the combustion device 4 mostly has a very high temperature, e.g. between 800 ° C and 1,200 ° C, in particular from 1,000 ° C. In order to use this heat energy, the flue gas derived from the combustion device 4, in particular before being fed into the coke gasifier 3, can be passed through the heat exchanger 14. A portion of the thermal energy contained in the flue gas can be withdrawn. E.g. the withdrawn heat energy of the drying device 7 for dehumidification and drying of the biomass to be treated 5 before being fed into the pyrolysis Re actuator 2 and thus used to reduce the moisture.

FIG. 2 shows and describes an embodiment variant of the treatment system 1 described in detail in FIG. 1 and the process steps that differ slightly therefrom or the process sequence that differs slightly therefrom. The same reference numerals or component names as in the previous FIG. 1 are used for the same parts. In order to avoid unnecessary repetition, reference is made to the detailed description in the preceding FIG. 1.

Except for the modified arrangement of the pyrolysis reactor 2 and the subsequently provided coke gasifier 3, the system structure of the treatment system 1 basically corresponds to that arrangement as shown and described in FIG. Therefore, a detailed description of the other parts of the system or system components is not given here. The description is to be transferred analogously from FIG. 1 to the embodiment shown.

It is provided in this embodiment that the coke gasifier 3 comprises a screw conveyor or is provided with it or is designed as a screw conveyor. This is shown schematically simplified. The coke gasifier 3 is preferably arranged below the pyrolysis reactor 2 and is in flow connection with it directly via its own connecting line 17. The connecting line 17 can for example be designed as a pipe in the form of a case shaft. The discharge area of the pyrolysis reactor 2 is thus in direct conveying or flow connection with the supply area of the coke gasifier 3. The connection line 17 connects the interior of the pyrolysis reactor 2 directly with the interior space of the coke gasifier 3. This means that the pyrolysis coke conveyed on from the pyrolysis reactor 2 can be conveyed or fed to the coke gasifier 3 while closing off the external ambient conditions.

It can also again be provided that the flue gas diverted from the combustion device 4, in particular before being fed into the coke gasifier 3, is passed through a filter device 13 and filtered in the process. Furthermore, oxygen, in particular in the form of ambient air, can be added to the flue gas before it is fed into the coke gasifier 3. The flue gas, optionally enriched with oxygen, can preferably be fed to the coke gasifier 3 at a pressure which is higher than the ambient atmospheric pressure. The feed line into the interior of the coke gasifier 3 can be fed to only one feed line position or also to several feed line positions arranged distributed over the longitudinal extent. The at least one feed line position is preferably arranged in a longitudinal section at the end of the coke gasifier 3.

The pyrolysis coke further treated in the coke gasifier 3 is forcibly conveyed further within the coke gasifier 3 from the supply area to the discharge area by the provision of the screw conveyor. By means of this forced conveying movement, better mixing and treatment of the pyrolysis coke in the coke gasifier 3 can also be achieved. As can be seen from the illustration in FIG. 2, the connecting line 17 has a predominantly low to completely vertical alignment. The coke gasifier housing can be designed as a hollow cylinder and thus as a tube. The longitudinal axis of the coke gasifier housing can preferably be oriented in an inclined manner with respect to a horizontal plane. The rising incline refers to the slope starting from the supply area towards the discharge area of the coke gasifier 3. However, it is also a horizontal alignment or a parallel alignment with respect to the longitudinal axis of the coke gasifier housing of the pyrolysis reactor 2 possible. Independently of this, however, an arrangement of the longitudinal axis of the coke gasifier housing sloping down from the supply area to the discharge area of the coke gasifier 3 could also be selected.

The further thermo-chemical treatment of the biomass 5, which can also be referred to as gasification material, takes place by feeding the flue gas, which may be enriched with oxygen, into the interior of the coke gasifier 3. Independently of this, it would also be possible, instead of the biomass 5, e.g. To thermally treat household waste, commercial waste or the like. Plastics and / or plastic composites can also be thermally treated in the treatment system 1 and pyrolysis gas and pyrolysis coke can be formed therefrom. By supplying at least the flue gas described above into the interior of the coke gasifier 3 with the higher gas pressure lying above the atmospheric air pressure, the gasification gas formed in the coke gasifier 3 is pressed within the coke gasifier 3 into the supply area of the pyrolysis coke. Subsequently, the gasifier gas is passed or pressed into the interior of the pyrolysis reactor 2 via the connecting line 17. This takes place in the countercurrent principle with respect to the conveying direction of the pyrolysis coke, in particular with a special pressure with respect to the ambient atmospheric pressure. The pyrolysis coke located in the connecting line 17 serves as a filter through which the gasifier gas must flow. The pyrolysis gas and the gasifier gas fed to the pyrolysis reactor 2 are then derived together from the interior of the pyrolysis reactor 2 and fed to the combustion device 4.

In this case it is still possible not only to feed the pyrolysis gas to the collecting container 12, but to feed both gases together to the collecting container 12 and from there to pass the mixture including the pyrolysis gas and the gasifier gas on to the combustion device 4.

The above-described partial amount or partial flow is a volume flow or a mass flow due to the process sequence and the ongoing operation of the treatment system 1. These flows indicate how much volume or what mass of a medium is transported through a specified cross-section per period of time. In the case of flowable fluids (liquids and / or gases), the volume flow is usually stated. FIG. 3 is a further possible embodiment variant of the treatment system 1 previously described in detail in FIG. 1 and the process steps that differ slightly therefrom or the process sequence that differs slightly therefrom is shown and described. The same reference numerals or component designations as in the preceding FIGS. 1 and 2 are again used for the same parts. In order to avoid unnecessary repetition, reference is made to the detailed description in the preceding FIGS. 1 and 2.

The system structure of the treatment system 1 basically corresponds to that arrangement as shown and described in FIG. 1. Therefore, the detailed description of the other parts of the system or system components is not given here. The description is to be transferred analogously from FIG. 1 to the embodiment shown here. It should be mentioned that the coke gasifier 3 can, independently of this, also be designed as it was previously described and shown in detail in FIG.

The gasifier gas diverted from the coke gasifier 3 separately from the residue product is in this embodiment before it is fed into the combustion device 4 and / or into the internal combustion engine 11 through a further heat exchanger 18 and thus a predetermined amount of heat is extracted from the gasifier gas. This intended reduction in the temperature of the carburetor gas is supplied to the Brennvorrich device 4 and / or the internal combustion engine 11 at a lower temperature. The temperature value of the cooled gasifier gas can originate or be selected from a temperature value range whose lower limit is 100 ° C., in particular 150 ° C., and whose upper limit is 400 ° C., in particular 250 ° C. A particularly preferred temperature value or temperature value range can e.g. 200 ° C ± 20 ° C.

This heat energy withdrawn from the gasifier gas by the further heat exchanger 18 can, for example, also be fed to the drying device 7 for dehumidifying and drying the biomass 5 to be treated before being fed into the pyrolysis reactor 2 and thus used to reduce the moisture. However, other system components can also be supplied with this thermal energy. Furthermore, return lines from the drying device 7 to the heat exchangers 14, 18, which have not been described in more detail before, are indicated and identified with the Roman numerals “I” and “II”. The line “I” here connects the first heat exchanger 14 to the drying device 7, with the other Line “II” also connects the further heat exchanger 18 with the drying device 7. However, it would also be possible, in addition to or instead of the drying device 7, to supply the heat energy withdrawn from the heat exchanger (s) 14, 18 with appropriate line connections. Mostly a closed circuit with supply lines and return lines is provided. Since this is considered to be generally known, the detailed illustration is omitted for the sake of clarity.

But it could also be supplied to the drainage device 6 with the shear of the or the Wärmetau 14, 18 by providing appropriate line connections.

In addition or independently of this, it would still be possible not to feed the flue gas to the coke gasifier 3, but rather oxygen mostly in the form of ambient air. For this purpose, an actuator 19 is indicated in the line connection between the admixing device 16 and the coke gasifier 3, which is possibly in communication with the control device 8. By means of the actuator 19, the supply of flue gas or oxygen, in particular in the form of ambient air, can be selected. The actuator 19 can e.g. be formed by a switching valve or the like.

As already described above, the flue gas can also be enriched with a certain proportion of oxygen, in particular in the form of ambient air. Depending on the supplied or supplied combustion gas or gas mixture (flue gas, flue gas + oxygen or oxygen, especially in the form of ambient air), the pyrolysis coke in the Koksverga ser 3 can be gasified with a temperature value that comes from a temperature range whose lower limit is 400 ° C , in particular 500 ° C, and its upper limit is 1,000 ° C, in particular 900 ° C.

If necessary, the oxygen-enriched flue gas and / or the oxygen, in particular in the form of ambient air, can preferably be fed to the coke gasifier 3 at a pressure that is higher than the ambient atmospheric pressure. For this purpose, a pressure-increasing element is shown schematically simplified. It should also be noted that the coke gasifier 3 generally described above can be designed or configured, for example, as a fixed bed, fluidized bed, screw or rotary tube reactor.

The exemplary embodiments show possible design variants, whereby it should be noted at this point that the invention is not limited to the specially shown design variant dersel ben, but rather various combinations of the individual design variants with one another are possible and this variation is possible based on the teaching on technical action The present invention is within the ability of those skilled in this technical field.

The scope of protection is determined by the claims. However, the description and the drawings should be used to interpret the claims. Individual features or feature combinations from the different exemplary embodiments shown and described can represent independent inventive solutions for themselves. The task on which the independent inventive solutions are based can be found in the description.

All information on value ranges in the objective description are to be understood in such a way that they include any and all sub-ranges, e.g. The indication 1 to 10 is to be understood in such a way that all sub-areas, starting from the lower limit 1 and the upper limit 10, are included, i.e. all subranges start with a lower limit of 1 or greater and end at an upper limit of 10 or less, e.g. 1 to 1.7, or 3.2 to 8, 1, or 5.5 to 10.

For the sake of order, it should finally be pointed out that, for a better understanding of the structure, some elements have been shown not to scale and / or enlarged and / or reduced. List of reference signs treatment plant

Pyrolysis reactor

Coke gasifier

Burning device

Biomass

Drainage device

Drying device

Control device

Lock system

Intermediate container

Internal combustion engine

Collection container

Filter device

Heat exchanger

stack

Proportioning device

Connecting line

Heat exchanger

Actuator

Claims

Patent claims

1. Process for thermo-chemi see treatment of biomass (5), in particular organic waste products such as sewage sludge, slaughterhouse waste, animal meal, excrement, and recovery of at least one valuable material contained in the biomass (5), in which the following steps in a treatment plant (1) be carried out:

Providing at least one pyrolysis reactor (2),

Providing at least one coke gasifier (3),

Providing at least one burning device (4),

Provision of the biomass to be treated (5),

Feeding the provided biomass (5) to be treated into the pyrolysis reactor (2),

Pyrolyzing the biomass (5) in the pyrolysis reactor (2) and thereby thermal decomposition of the biomass (5) in pyrolysis coke and pyrolysis gas,

spatially separated removal of the pyrolysis coke and removal of the pyrolysis gas from the pyrolysis reactor (2),

Further conveying and feeding the pyrolysis coke into the coke gasifier (3), gasifying the pyrolysis coke in the coke gasifier (3), the pyrolysis coke being further decomposed into a solid, in particular free-flowing, residue product and into a gasifier gas, and the residue product contains the at least one valuable substance ,

spatially separate removal of the residue product and removal of the gasifier gas from the coke gasifier (3),

Feeding the pyrolysis gas derived from the pyrolysis reactor (2) into the combustion device (4), the pyrolysis gas being burned with the formation of a flue gas in the combustion device (4), and discharging the flue gas from the combustion device (4),

Feeding the carburetor gas derived from the coke gasifier (3) into the combustion device (4), wherein the gasifier gas is burned in the combustion device (4) to form the flue gas and is also discharged from this, and / or feeding the gasifier from the coke ( 3) diverted carburetor gas into an internal combustion engine (11), and

Feeding at least a portion of the flue gas diverted from the combustion device (4) into the coke gasifier (3).

2. The method according to claim 1, characterized in that the pyrolysis gas formed in the pyrolysis reactor (2) immediately after it is discharged from the pyrolysis reactor (2) and before it is passed on to the combustion device (4) in a collecting container (12) collects and there are still dust-like fractions in the pyrolysis gas in the collecting container (12).

3. The method according to claim 1 or 2, characterized in that the pyrolysis gas and / or the gasifier gas are or will be fed to the combustion device (4) at a temperature of at least 400 ° C.

4. The method according to claim 1 or 2, characterized in that the gas before being fed into the combustion device (4) and / or before being fed into the combustion engine (11) heat energy is withdrawn and is cooled to a temperature value that originates from a temperature range whose lower limit is 100.degree. C., in particular 150.degree. C., and whose upper limit is 400.degree. C., in particular 250.degree.

5. The method according to any one of the preceding claims, characterized in that the pyrolysis gas and the gasifier gas are passed to the combustion device (4) separately from one another.

6. The method according to any one of the preceding claims, characterized in that the pyrolysis coke discharged from the pyrolysis reactor (2) is conveyed into an intermediate container (10) before being fed into the coke gasifier (3).

7. The method according to claim 6, characterized in that the pyrolysis coke from the intermediate container (10) is conveyed to the coke gasifier (3) by means of a screw conveyor and a screw feeder located downstream of the conveyor screw.

8. The method according to any one of claims 1 to 3, characterized in that the coke gasifier (3) comprises a screw conveyor and the pyrolysis coke conveyed further from the pyrolysis reactor (2) by means of a connecting line (17) directly and completed from the external environmental conditions Coke gasifier (3) is supplied.

9. The method according to any one of the preceding claims, characterized in that the flue gas derived from the combustion device (4), in particular before being fed into the coke gasifier (3), passed through a heat exchanger (14) and thermal energy is extracted from the flue gas.

10. The method according to any one of the preceding claims, characterized in that the flue gas derived from the combustion device (4), in particular before being fed into the coke gasifier (3), is passed through a filter device (13) and filtered in the process.

11. The method according to any one of the preceding claims, characterized in that the flue gas is admixed with oxygen, in particular in the form of ambient air, before it is fed into the coke gasifier (3).

12. The method according to any one of claims 8 to 11, characterized in that the flue gas, optionally enriched with oxygen, is fed to the coke gasifier (3) at a higher pressure than the ambient atmospheric pressure.

13. The method according to any one of claims 8 to 12, characterized in that the gasifier gas formed in the coke gasifier (3) is fed from this via the connecting line (17) to the pyrolysis reactor (2), in particular with a higher than the atmospheric ambient pressure Pressure is supplied.

14. The method according to claim 13, characterized in that the pyrolysis gas and the gasifier gas fed to the pyrolysis reactor (2) are fed together to the combustion device (4).

15. The method according to any one of the preceding claims, characterized in that the pyrolysis coke in the coke gasifier (3) is gasified with a temperature value that comes from a temperature range, the lower limit of 400 ° C, in particular 500 ° C, and the upper limit Limit is 1,000 ° C, in particular 900 ° C.

16. The method according to claim 15, characterized in that the temperature value for gasification of the pyrolysis coke in the coke gasifier (3) is set to the flue gas by means of the proportion of added oxygen, in particular of mixed ambient air.

17. The method according to any one of the preceding claims, characterized in that at least a proportion of the biomass to be treated (5) before being fed into the pyrolysis reactor (2) by means of a dewatering device (6) is dewatered to a moisture value that consists of a moisture -Value range originates, the lower limit of which is 70% by weight, in particular 80% by weight, and the upper limit of which is 95% by weight, in particular 90% by weight.

18. The method according to any one of the preceding claims, characterized in that at least a proportion of the biomass to be treated (5) before being fed into the pyrolysis reactor (2) by means of a drying device (7) is dried to a moisture value that is derived from a Moisture value range originates, the lower limit of which is 3% by weight, in particular 5% by weight, and the upper limit of which is 20% by weight, in particular 10% by weight.

19. The method according to claim 17 or 18, characterized in that the thermal energy extracted from the flue gas in the heat exchanger (14) is fed to the drying device (7).

20. The method according to any one of the preceding claims, characterized in that the mass flow of the pyrolysis reactor (2) supplied biomass (5) is determined.

21. The method according to any one of the preceding claims, characterized in that the biomass to be treated (5) is fed to the pyrolysis reactor (2) in a gas-tight manner by means of a lock system (9).