Pyrolysis plant
Patent Information
- Application Number
- PCT/EP2026/056179
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- Priority Date
- 2025-03-21
- Filing Date
- 2026-03-06
- Publication Date
- 2026-09-24
Smart Images
Figure EP2026056179_24092026_PF_FP_ABST
Abstract
Description
[0001] 12953 / 1 / 2_WO Fixed bed cleaning
[0002] Pyrolysis plant
[0003] The present invention relates to a pyrolysis plant for producing pyrolysis gas and solid pyrolysate from a carbon-containing substrate.
[0004] A pyrolysis plant is used for the thermal decomposition of organic or carbon-containing substrates under conditions of oxygen exclusion or deficiency. These plants have diverse applications, particularly in the recycling of waste such as plastics, biomass, or used tires. The resulting products can be used as raw materials or energy carriers.
[0005] A particular application of pyrolysis plants is the production of biochar, also known as terra preta charcoal, from biomass. Biochar is used in agriculture as a soil improver to enhance soil structure and retain water and nutrients. Furthermore, biochar enables the long-term sequestration of carbon, thus allowing for the long-term removal of carbon dioxide from the atmosphere.
[0006] In addition to biochar, the pyrolysis of biomass also produces pyrolysis gas, a gas mixture typically consisting mainly of carbon monoxide (CO), hydrogen (H2), carbon dioxide (CO2), methane (CH4), as well as small amounts of oxygen (O2), nitrogen (N2), and aliphatic and aromatic hydrocarbons (CxHx). Trace amounts of other organic decomposition products from pyrolysis are also possible.
[0007] Pyrolysis gas is versatile and can be used, among other things, as a fuel for energy production, for example in gas turbines, gas engines, or gas-fired boiler systems for the production of hot water or steam.
[0008] However, pyrolysis gas contains undesirable impurities that complicate its direct use and further processing. These impurities include, in particular, tar and pitch (low volatility 12953 / 1 / 2_WO fixed bed cleaning).
[0009] Organic compounds, dust particles, sulfur compounds such as hydrogen sulfide (H₂S), nitrogen compounds such as ammonia (NH₃), and alkali compounds. Before the pyrolysis gas can be used, these contaminants must be at least partially removed to prevent damage to downstream equipment and environmental pollution.
[0010] The purification of the pyrolysis gas is quite complex and is typically carried out by mechanical separation processes (e.g.
[0011] cyclone separators or filters), thermal post-treatment (e.g.
[0012] Tar cracking), chemical absorption (e.g., with zinc oxide or sodium hydroxide), and / or physical processes such as gas scrubbing or condensation. The effective removal of these impurities is crucial for improving the quality of the pyrolysis gas and fully exploiting its diverse applications.
[0013] From the extensive prior art, reference is made, by way of example, to documents DE 10 2012 004 632 B4 and EP 3 285 920 Bl. Both describe a pyrolysis plant for producing pyrolysis gas and solid pyrolysate from a carbon-containing substrate.
[0014] German patent DE 10 2017 123 600 B4 describes a plant for the thermal processing of contaminated organic waste to produce gas, oil, and activated carbon. For the utilization of organic waste through thermal decomposition into coke and fluid hydrocarbons, the coarsely shredded organic waste is fed via a material airlock to a melting reactor and melted into a pasty mass. This pasty mass is then fed via another material airlock to a coke reactor located below the melting reactor. In the coke reactor, a screw conveyor conveys the material to a coke transfer shaft and thermally decomposes it into coke and pyrolysis gas by heating. The pyrolysis gas released in this process is routed via a gas line from the coke reactor to a tar separator, where it is freed from tar and heavy oils.The gas, thus freed from tar and heavy oils, is fed to an oil separator, cooled there and in 12953 / 1 / 2_WO fixed bed cleaning.
[0015] Light oil and clean gas are separated. Part of the clean gas can be used to heat the coke reactor and the tar cracking reactor.
[0016] Utility model DE 20 2017 002 898 Ul describes a sewage sludge gasifier that degasses dried sewage sludge by means of staged pyrolysis to produce synthesis gas and biochar. The gasifier comprises a cooling and cleaning coil followed by gasifier tubes. The sewage sludge is dried and fed to the cooling and cleaning coil via a rotary valve. In the cooling and cleaning coil, the synthesis gas generated in the gasifier tubes is cooled and purified in a countercurrent process. During this process, the sewage sludge absorbs condensates and long-chain hydrocarbons. Following the cooling and cleaning coil, the clarified sludge is conveyed into the gasifier tubes and broken down into synthesis gas and biochar. At the end of the gasifier tubes, the carbonized biochar is discharged via another rotary valve.
[0017] Against this background, the present invention is based on the objective of providing a pyrolysis plant of the type described above, which is characterized by improved practicality, in particular with regard to reliable, simple and cost-effective cleaning of the pyrolysis gas as well as low environmental impact during plant operation.
[0018] This problem is solved by the pyrolysis plant according to claim 1 and the corresponding method according to claim 8. Particularly advantageous embodiments of the invention are described in the dependent claims.
[0019] The pyrolysis plant according to the invention for producing pyrolysis gas and solid pyrolysate from a carbon-containing (liquid and / or solid) substrate comprises
[0020] a substrate feeder,
[0021] A fixed bed cleaning system with a substrate inlet, a substrate outlet, and a cleaning auger suitable for conveying solid substrate from the substrate inlet to the substrate outlet, 12953 / 1 / 2_WO fixed bed cleaning
[0022] a first lock with an inlet connected to the substrate feed and an outlet connected to the substrate inlet of the fixed bed cleaning system, suitable for transferring solid substrate from the inlet to the outlet,
[0023] a reactor with a reactor housing, a reactor inlet arranged in the reactor housing, a reactor outlet arranged in the reactor housing and a rotatable reactor screw conveyor in the reactor housing, which is suitable for conveying solid substrate from the reactor inlet to the reactor outlet, a reactor heater by which the reactor can be heated via the reactor housing,
[0024] a second lock with an inlet connected to the substrate outlet and with an outlet connected to the reactor inlet, suitable for transferring solid substrate from the inlet to the outlet,
[0025] a pyrolysate discharge,
[0026] a third lock with an inlet connected to the reactor outlet and an outlet connected to the pyrolysate discharge, suitable for transferring solid substrate from the inlet to the outlet,
[0027] a pyrolysis gas line that enters the reactor in the area of the reactor outlet and that opens into the fixed bed cleaning system in the area of the substrate outlet, and is designed to allow a flow of pyrolysis gas from the reactor into the fixed bed cleaning system, and
[0028] a pyrolysis gas outlet in the area of the substrate inlet of the fixed bed cleaning system, through which the pyrolysis gas can be removed from the fixed bed cleaning system (i.e., extracted from the fixed bed cleaning system).
[0029] The synergistic interplay of the features according to the invention enables the realization of a pyrolysis plant in which the resulting pyrolysis gas can be purified simply, reliably, and cost-effectively by passing it against the flow direction of the substrate (or biomass) in the fixed-bed cleaning process. During this flow through the substrate, the pyrolysis gas releases at least some of its impurities to the substrate, so that the impurities re-enter the reactor with the substrate, where they are then processed.
[0030] Due to the high temperatures present, they are thermally and / or chemically decomposed, thus contributing to an increase in the amount of pyrolysis gas or solid pyrolysate produced. This allows for an increase in process yield and a significant reduction in the effort required for downstream, external pyrolysis gas purification.
[0031] Furthermore, the pyrolysis gas, which has a relatively high temperature level upon entering the fixed-bed cleaning system, transfers at least some of its thermal energy to the substrate conveyed in the opposite direction as it flows through the system. This preheats and dries the substrate.
[0032] This internal heat recovery contributes to the efficiency of the pyrolysis process.
[0033] The following section provides a detailed explanation and definition of selected terms and features used to describe the invention.
[0034] The substrate feed allows (solid and / or liquid) substrate to be supplied to the pyrolysis plant by conveying it to the inlet of the first sluice.
[0035] A lock is used for the (metered) conveyance of solids from the lock inlet to the lock outlet, while simultaneously preventing gas exchange as much as possible.
[0036] Pressure equalization between the outlet and the inlet. Locks thus form a kind of gas barrier that largely prevents the backflow of gases from the lock outlet to the lock inlet.
[0037] The fixed-bed cleaning system features a housing in which the substrate inlet and outlet are located, and in which the cleaning auger rotates. Substrate can thus be introduced through the inlet into an interior space enclosed by the housing, and then conveyed to the substrate by the rotation of the auger.
[0038] The fluid is expelled and exits the interior through the substrate outlet.
[0039] Similarly, substrate can be introduced through the reactor inlet into an interior space enclosed by the reactor housing, conveyed to the reactor outlet by rotation of the reactor screw conveyor, and exit the interior space again through the reactor outlet.
[0040] Both the fixed bed cleaning system and the reactor can each have not just a single screw conveyor, but several screw conveyors connected in series to convey the substrate from the respective inlet to the respective outlet.
[0041] The cleaning screw conveyor ( n) and the reactor screw conveyor ( n) can each be designed in particular as a full thread screw conveyor ( n) or as a spiral screw conveyor ( n) (open in its core).
[0042] The fixed-bed cleaning system and the reactor form two separate process areas, each enclosed by two airlocks. The unpurified pyrolysis gas is discharged from the reactor at the reactor outlet and fed into the fixed-bed cleaning system via the pyrolysis gas line at the substrate outlet. The pyrolysis gas then flows through the fixed-bed cleaning system against the substrate conveying direction, is purified, and exits the system at the substrate inlet through the pyrolysis gas outlet. This pyrolysis gas flow pattern results from the slightly lower pressure in the fixed-bed cleaning system compared to the reactor. This is made possible by the clever arrangement of the three airlocks.
[0043] The pyrolysis gas line enters the reactor at a first pipe opening in the area of the reactor outlet. This indicates that the distance of the first pipe opening from the reactor outlet is less than the distance of the first pipe opening from the reactor inlet, or that the distance of the first pipe opening from the reactor outlet is at most half, one-third, one-fifth, or 12953 / 1 / 2_WO fixed bed cleaning
[0044] one tenth of the distance between the first pipe outlet and the reactor inlet.
[0045] In this context, the term "distance between two points lying on a flow path" refers to the distance a gas would have to travel in order to get from one point to the other along that flow path.
[0046] A second end of the pyrolysis gas line connects to the fixed-bed cleaning system via a second pipe outlet near the substrate outlet. As explained above, this means that the distance of the second pipe outlet from the substrate outlet is less than the distance of the second pipe outlet from the substrate inlet, or that the distance of the second pipe outlet from the substrate outlet is at most half, one-third, one-fifth, or one-tenth of the distance of the second pipe outlet from the substrate inlet.
[0047] The statement that the pyrolysis gas outlet is located in the area of the substrate inlet of the fixed bed cleaning system expresses that the distance of the pyrolysis gas outlet from the substrate inlet is smaller than the distance of the pyrolysis gas outlet from the substrate outlet, or that the distance of the pyrolysis gas outlet from the substrate inlet is at most half, one third, one fifth or one tenth of the distance of the pyrolysis gas outlet from the substrate outlet.
[0048] A key difference between the fixed-bed cleaning process area and the reactor process area is that the reactor housing can be heated, while the fixed-bed cleaning housing cannot. Heating the substrate via the housing is also referred to as external or indirect heating. This allows the substrate in the reactor to be heated to the high temperature required for pyrolysis, typically between 400 and 700 °C.
[0049] In contrast, in the fixed-bed cleaning process, the housing is not heated. However, the substrate is still heated and dried, as it comes into direct contact with the relatively hot pyrolysis gas, which is directed through the fixed-bed cleaning system in the opposite direction to the substrate flow.
[0050] The starting material for the pyrolysis process is called the substrate. A pyrolysis product is called the pyrolysate. A solid substrate or solid pyrolysate exhibits a defined, dimensionally stable structure under laboratory conditions (20°C, 1.01325 bar) and can be present in granulated, powdered, or chopped form.
[0051] Against this background, a first particularly advantageous embodiment of the invention provides that
[0052] The fixed bed cleaning system has a fixed bed cleaning housing in which the substrate inlet and substrate outlet are arranged and in which the cleaning conveying screw is rotatable, and no heating system is provided by means of which the fixed bed cleaning housing can be heated.
[0053] In this way, a particularly cost-effective and at the same time efficient pyrolysis plant can be realized.
[0054] Advantageously, the substrate feed includes a substrate auger suitable for conveying solid substrate to the inlet of the first lock.
[0055] In order to convey the substrate through the pyrolysis plant particularly efficiently and at the same time reduce the pressure equalization between adjacent process areas as much as possible, it is particularly advantageous if at least one of the locks is designed as a rotary valve, double flap lock or slide valve (flat slide valve).
[0056] A double-flap airlock is a device that enables controlled material transfer between adjacent process areas with different pressures or gas atmospheres.12953 / 1 / 2_WO Fixed bed cleaning
[0057] This enables it, while at the same time largely preventing unwanted gas exchange.
[0058] A double-flap lock consists of two flaps arranged one behind the other, which are opened and closed alternately. First, the upper flap opens, allowing the material to be transferred to fall by gravity from the lock inlet into a lock chamber. The upper flap then closes, trapping the material in the lock chamber. Finally, the lower flap opens, allowing the material to fall from the lock chamber into the lock outlet.
[0059] The lower flap is then closed again and the cycle starts anew.
[0060] A rotary valve, on the other hand, has as its core component a (often rotationally symmetrical) rotary valve with radial vanes that span several (typically equally sized) cells. The rotary valve is located in a valve housing with an upper and a lower opening and is continuously rotated.
[0061] The material to be transferred falls by gravity from the inlet through the upper opening into the cell of the rotary valve that has just been released through the upper opening. As the rotary valve rotates, the filled cell is then turned away from the upper opening. Upon reaching the lower opening, the filled cell empties into the outlet of the airlock.
[0062] In a slide gate (also called a flat slide gate or plate slide gate), the material to be transferred is pushed through a slide plate from an inlet area to an outlet area of the gate.
[0063] According to a further particularly advantageous embodiment of the pyrolysis plant, it comprises a pyrolysis gas extraction system configured to extract pyrolysis gas from the fixed bed cleaning system via the pyrolysis gas outlet. 12953 / 1 / 2_WO Fixed bed cleaning
[0064] The pyrolysis gas extraction can be implemented in particular as a (induced draft) blower or as a jet pump.
[0065] An induced draft fan is a device for creating a vacuum in order to selectively extract and transport gases. For this purpose, an induced draft fan typically has a rotating impeller which causes the gas to be extracted to be drawn in through a suction opening and released again through an outlet opening.
[0066] A jet pump is a conveying device that works on the principle of the jet or Venturi effect to extract and transport liquids or gases.
[0067] By extracting the pyrolysis gas, a negative pressure can be created in the fixed-bed cleaning process relative to the reactor and the substrate feed. This negative pressure causes the pyrolysis gas to flow along the desired pyrolysis gas flow path according to the invention and prevents unwanted passage of the pyrolysis gas through the airlocks.
[0068] To remove deposits on the back of the cleaning screw conveyor, it may be provided that the direction of rotation of the cleaning screw conveyor is reversible.
[0069] According to a further particularly preferred embodiment of the invention, the pyrolysis plant according to the invention comprises
[0070] a pyrolysis gas cleaning system for separating dusts, condensable substances and / or unwanted gases from the pyrolysis gas discharged from the pyrolysis gas outlet, and a reactor heating system comprising a pyrolysis gas burner, by means of which the reactor can be heated, wherein (at least) a portion of the separated dusts, condensable substances and / or unwanted gases can be fed to the pyrolysis gas burner and combusted there.
[0071] In this way, the impurities present in the form of deposited dusts or condensable substances of the 12953 / 1 / 2_WO fixed bed cleaning can be removed.
[0072] Pyrolysis gas is thermally decomposed through combustion and thus disposed of. This eliminates the need for complex and expensive separate disposal of the contaminants.
[0073] The pyrolysis gas produced by the pyrolysis plant can be burned as fuel in the pyrolysis gas burner. Either all of the pyrolysis gas or only a portion of it can be used for this purpose.
[0074] According to a further preferred embodiment of the pyrolysis plant according to the invention
[0075] The cleaning conveyor screw is designed as a hollow spiral screw, through whose center a cavity extends in the longitudinal direction, and
[0076] The fixed bed cleaning system has a scraper chain (especially designed as a metallic chain) which is attached to the two opposite ends of the hollow spiral screw at attachment points in such a way that it extends through the cavity of the hollow spiral screw and sags due to gravity to such an extent that it comes into contact with the hollow spiral screw at at least one further contact point between the two attachment points.
[0077] The gravity-induced sagging scraper chain rests on at least one contact point on the hollow spiral screw and thus continuously scrapes along the rotating screw. This allows any tar and pitch deposits that form on the hollow spiral screw to be mechanically removed and fed into the pyrolysis process. The continuous cleaning of the hollow spiral screw also improves the conveying efficiency of the screw conveyor.
[0078] Such a conveying section with a hollow spiral screw, through whose cavity a scraper chain extends, constitutes an independent invention, even apart from its application in a pyrolysis plant. The applicant therefore reserves the right to claim protection for the following conveying section as well: 12953 / 1 / 2_WO Fixed bed cleaning
[0079] Conveyor line for conveying a solid substrate comprising
[0080] a (cylindrical) housing with an inlet and an outlet,
[0081] a screw conveyor arranged in the housing, suitable for conveying solid substrate from the inlet to the outlet, and a scraper chain (especially designed as a metallic chain),
[0082] where
[0083] the screw conveyor is designed as a hollow spiral screw, through whose center a cavity extends in the longitudinal direction, and
[0084] The stripping chain is attached to the two opposite ends of the hollow spiral screw at attachment points in such a way that it extends through the cavity of the hollow spiral screw and sags due to gravity to such an extent that it comes into contact with the hollow spiral screw at at least one further contact point between the two attachment points.
[0085] Furthermore, the present invention manifests itself in the method according to claim 8 for producing a pyrolysis gas and a (solid) pyrolysate from a carbon-containing (solid) substrate with a pyrolysis plant according to the invention comprising the following steps:
[0086] Filling the fixed bed cleaning system and the reactor of the pyrolysis plant with substrate and conveying the substrate using the cleaning screw conveyor and the reactor screw conveyor, and, via the pyrolysis gas line, removing the pyrolysis gas from the reactor in the area of the reactor outlet and introducing the pyrolysis gas into the fixed bed cleaning system in the area of the substrate outlet of the fixed bed cleaning system.
[0087] Flow of the pyrolysis gas through the fixed bed cleaning system from the substrate outlet area to the pyrolysis gas outlet in the substrate inlet area (and thus against the substrate conveying direction), and
[0088] Discharge of pyrolysis gas from the pyrolysis gas outlet. 12953 / 1 / 2_WO Fixed bed cleaning
[0089] Two exemplary embodiments of the invention are explained in more detail below with reference to the drawing. The drawing shows
[0090] Fig. 1 shows a schematic representation of a first embodiment of the pyrolysis plant 1 according to the invention.
[0091] Fig. 2 shows a schematic representation of a second embodiment of the pyrolysis plant according to the invention.
[0092] The pyrolysis plant 1 according to Figure 1 comprises four process areas, namely a substrate feed 2, a fixed bed cleaning 3 with a substrate inlet 4 and a substrate outlet 5, a reactor 6 with a reactor inlet 7 and a reactor outlet 8 and a pyrolysate discharge 9.
[0093] Between adjacent process areas, a rotary valve 10, 11, 12 with an inlet 10.1, 11.1, 12.1 and an outlet 10.2, 11.2, 12.2 is arranged. The rotary valves are each driven by an electric motor 13, 14, 15.
[0094] The inlet 10.1 of a first lock 10 is connected to the substrate feed 2, the outlet 10.2 of the first lock 10 is connected to the substrate inlet 4 of the fixed bed cleaning 3.
[0095] The inlet 11.1 of the second lock 11 is connected to the substrate outlet 5 of the fixed bed cleaning system 3, the outlet 11.2 of the second lock 11 is connected to the reactor inlet 7 of the reactor 6.
[0096] The inlet 12.1 of the third lock 12 is connected to the reactor outlet 8 of the reactor 6, the outlet 12.2 of the third lock 12 is connected to the pyrolysate outlet 9.
[0097] The fixed bed cleaning system 3 has two cleaning sections 17, 18 connected by a connecting channel 16, each comprising a fixed bed cleaning housing 17.1, 18.1 and a cleaning conveyor screw 17.2, 18.2 rotatable within the fixed bed cleaning housing 17.1, 18.1 by means of an electric motor 19, 20. (Im12953 / 1 / 2_WO Fixed bed cleaning)
[0098] In normal operation, substrate 21 is first conveyed by one of the two cleaning screw conveyors 17.2 from the substrate inlet 4 to the connecting channel 16 and then by the second of the two cleaning screw conveyors 18.2 from the connecting channel 16 to the substrate outlet 5.
[0099] Reactor 6 also has two reactor sections 23, 24 connected by a connecting channel 22, each comprising a reactor housing 23.1, 24.1 and a reactor screw conveyor 23.2, 24.2 rotatable within the reactor housing by means of an electric motor 25, 26. The reactor housings 23.1, 24.1 can be heated externally by means of a reactor heater 27 of reactor 6.
[0100] Pyrolysis plant 1 also has a pyrolysis gas line 28 and a pyrolysis gas outlet 29. The pyrolysis gas line 28 connects reactor 6 to the fixed-bed cleaning system 3: a first line outlet 28.1 of the pyrolysis gas line 28 opens into reactor 6 in the area of reactor outlet 8, and a second line outlet 28.2 of the pyrolysis gas line 28 opens into the fixed-bed cleaning system 3 in the area of substrate outlet 5.
[0101] Pyrolysis gas 30 can be extracted (discharged) from the fixed bed cleaning system 3 via the pyrolysis gas outlet 29 located in the area of the substrate inlet 4. For this purpose, a pyrolysis gas extraction system 31, designed as a blower, is provided in the pyrolysis gas outlet 29, which creates a negative pressure in the fixed bed cleaning system 3 relative to the reactor 6 and the substrate feed 2.
[0102] The substrate 21, which has been converted into a (solid) pyrolysate 32, can be discharged from the pyrolysis plant 1 via the pyrolysate discharge 9.
[0103] In order to produce a pyrolysis gas 30 and a solid pyrolysate in the intended operation of the pyrolysis plant 1, the following procedure must be followed:
[0104] First, the fixed bed cleaning 3 and the reactor 6 with a carbon-containing, mostly organic, solid substrate 21 to 12953 / 1 / 2_WO fixed bed cleaning
[0105] The reactor 6 is heated by means of the reactor heater 27, and the substrate 21 is conveyed by rotating the screw conveyors 17.2, 18.2, 23.2, 24.2 in the fixed-bed cleaning unit 3 and in the reactor 6. The rotary valves of the three airlocks 10, 11, 12 rotate to convey the substrate 21 from the substrate feed 2 into the fixed-bed cleaning unit 3 and from the fixed-bed cleaning unit 3 into the reactor 6, and to convey substrate 21 converted to pyrolysate 32 from the reactor 6 into the pyrolysate discharge 9.
[0106] The pyrolysis gas 30 produced in reactor 6 during pyrolysis is discharged via the first pipe opening 28.1 in the area of the reactor outlet 8 via the pyrolysis gas line 28 and introduced into the fixed bed cleaning system 3 via the second pipe opening 28.2 in the area of the substrate outlet 5.
[0107] Due to the negative pressure at the pyrolysis gas outlet 29, the pyrolysis gas 30 is drawn through the fixed-bed cleaning unit 3 to the pyrolysis gas outlet 29, opposite to the substrate conveying direction, and discharged from the pyrolysis unit 1. Through direct contact between the pyrolysis gas 30 and the substrate 21, the relatively hot pyrolysis gas 30 is freed from impurities and cooled, while the substrate 21 is dried and warmed. The impurities migrate with the substrate 21 into the reactor 6, where they are (at least largely) thermally decomposed.
[0108] The second embodiment of the pyrolysis plant 1 according to Figure 2 comprises, in addition to the pyrolysis plant 1 according to Figure 1, a separate pyrolysis gas purification unit 33 and a pyrolysis gas burner 34 encompassed by the reactor heater 27.
[0109] The pyrolysis gas cleaning unit 33 is fluidically connected to the pyrolysis gas outlet 29 via a line 35 and to the pyrolysis gas extraction unit 31 via a gas outlet 36. Its purpose is to separate dust and / or condensable substances from the pre-cleaned pyrolysis gas 30 discharged from the pyrolysis gas outlet 29. The pyrolysis gas 30, further cleaned in this way, leaves the pyrolysis gas cleaning unit 33 via the gas outlet 36, and the separated impurities via the condensate outlet 37.
[0110] A portion of the pyrolysis gas 30, which leaves the pyrolysis gas purification unit 33 via the gas outlet 36, is fed via a line 35 to the pyrolysis gas burner 34 and combusted there to heat the reactor 6. The remaining portion of the pyrolysis gas 30 is discharged from the pyrolysis plant 1 via a pyrolysis gas discharge 38 for other, external use.
[0111] The impurities discharged via the condensate outlet 37 (deposited dusts and / or condensable substances) are fed to the pyrolysis gas burner 34 via a condensate line 39 and combusted there. Alternatively or additionally, the separated dusts and / or condensable substances discharged via the condensate outlet 37 can be fed to the reactor 6 (via the reactor inlet 7) via another condensate line 42, which opens into the reactor inlet 7, in order to be at least partially converted into pyrolysis gas and / or solid pyrolysate there.
[0112] The exhaust gases 40 from the pyrolysis gas burner 34 leave the reactor heater 27 via an exhaust gas outlet 41.12953 / 1 / 2_WO fixed bed cleaning
[0113] Reference sign
[0114] Pyrolysis plant 1
[0115] Substrate feed 2
[0116] Fixed bed cleaning 3
[0117] Substrate inlet 4
[0118] Substrate outlet 5
[0119] Reactor 6
[0120] Reactor inlet 7
[0121] Reactor outlet 8
[0122] Pyrolysate removal 9
[0123] Locks 10, 11, 12
[0124] Lock inlet 10.1, 11.1, 12.1 Lock outlet 10.2, 11.2, 12.2 Electric motor 13, 14, 15, 19, 20, 25, 26 Connecting channel 16, 22 Cleaning sections 17, 18 Fixed bed cleaning housing 17.1, 18.1
[0125] Cleaning screw conveyor 17.2, 18.2
[0126] Substrate 21
[0127] Reactor sections 23, 24
[0128] Reactor housing 23.1, 24.1
[0129] Reactor screw conveyor 23.2, 24.2
[0130] Reactor heating 27
[0131] Pyrolysis gas line 28
[0132] First pipeline outlet 28.1
[0133] second pipe outlet 28. 2
[0134] Pyrolysis gas outlet 29
[0135] Pyrolysis gas 30
[0136] Pyrolysis gas extraction 31
[0137] Pyrolysate 32
[0138] Pyrolysis gas purification 33
[0139] Pyrolysis gas burner 34
[0140] Line 35
[0141] Gas outlet 36
[0142] Condensate outlet 37
[0143] Pyrolysis gas removal 38
[0144] Condensate line 39, 4212953 / 1 / 2_WO Fixed bed cleaning
[0145] Exhaust gases 40 Exhaust gas outlet 41
Claims
12953 / 1 / 2_WO Fixed bed cleaning Patent claims 1. Pyrolysis plant ( 1 ) for producing pyrolysis gas ( 30 ) and solid pyrolysate ( 32 ) from a carbon-containing substrate ( 21 ) comprising a substrate feeder ( 2 ), a fixed bed cleaning system ( 3 ) with a substrate inlet ( 4 ), a substrate outlet ( 5 ) and a cleaning conveying screw (17.2, 18.2) suitable for conveying solid substrate from the substrate inlet ( 4 ) to the substrate outlet ( 5 ), a first lock (10) with an inlet (10.1) connected to the substrate feed (2) and with an outlet (10.2) connected to the substrate inlet (4) of the fixed bed cleaning (3), suitable for transferring solid substrate from the inlet (10.1) to the outlet (10.2), a reactor (6) with a reactor housing (23.1, 24.1), a reactor inlet (7) arranged in the reactor housing, a reactor outlet (8) arranged in the reactor housing and a rotatable reactor screw conveyor (17.2, 18.2) in the reactor housing, which is suitable for conveying solid substrate from the reactor inlet (7) to the reactor outlet (8), a reactor heater (27) by which the reactor (6) can be heated via the reactor housing (23.1, 23.2), a second lock (11) with an inlet (11.1) connected to the substrate outlet (5) and with an outlet (11.2) connected to the reactor inlet (7), suitable for transferring solid substrate from the inlet (11.1) to the outlet (11.2), a pyrolysate discharge ( 9 ), a third lock ( 12 ) with an inlet ( 12. 1 ) connected to the reactor outlet ( 8 ) and with an outlet ( 12. 2 ) connected to the pyrolysate discharge ( 9 ), suitable for transferring solid substrate from the inlet ( 12. 1 ) to the outlet ( 12. 2 ), a pyrolysis gas line ( 28 ) which leads into the reactor ( 6 ) in the area of the reactor outlet ( 8 ) and which in the area 12953 / 1 / 2_WO fixed bed cleaning of the substrate outlet ( 5 ) into the fixed bed cleaning system ( 3 ), and is designed to allow a flow of pyrolysis gas ( 30 ) from the reactor ( 6 ) into the fixed bed cleaning system ( 3 ), and a pyrolysis gas outlet ( 29 ) in the area of the substrate inlet ( 4 ) of the fixed bed cleaning ( 3 ), through which the pyrolysis gas ( 30 ) can be discharged from the fixed bed cleaning ( 3 ).
2. Pyrolysis plant ( 1 ) according to claim 1, wherein the fixed bed cleaning ( 3 ) has a fixed bed cleaning housing ( 17. 1, 18. 1 ) in which the substrate inlet ( 4 ) and the substrate outlet ( 5 ) are arranged and in which the cleaning conveying screw (17.2, 18.2) is rotatable, and no heating is provided by means of which the fixed bed cleaning housing ( 17. 1, 18. 1 ) can be heated.
3. Pyrolysis plant ( 1 ) according to one of the preceding claims, wherein the substrate feed ( 2 ) comprises a substrate conveying screw which is suitable for conveying solid substrate to the inlet ( 10. 1 ) of the first sluice ( 10 ).
4. Pyrolysis plant ( 1 ) according to one of the preceding claims, wherein at least one of the locks ( 10, 11, 12 ) is designed as a rotary valve, double flap lock or gate valve.
5. Pyrolysis plant ( 1 ) according to one of the preceding claims, comprising a pyrolysis gas extraction system ( 31 ) which is configured to extract pyrolysis gas ( 30 ) from the fixed bed cleaning system ( 3 ) via the pyrolysis gas outlet ( 29 ).
6. Pyrolysis plant (1) according to one of the preceding claims, wherein the direction of rotation of the cleaning conveyor screw (17.2, 18.2) is reversible in order to remove deposits on the back side of the cleaning conveyor screw (17.2, 18.2). 12953 / 1 / 2_WO Fixed bed cleaning 7. Pyrolysis plant ( 1 ) according to any one of the preceding claims, comprising a pyrolysis gas cleaning system ( 33 ) for the removal of dusts and / or condensable substances from the pyrolysis gas ( 30 ) discharged from the pyrolysis gas outlet ( 29 ), and a reactor heater (27) comprising a pyrolysis gas burner (34) by means of which the reactor (6) can be heated, wherein at least a part of the separated dusts and / or condensable substances can be fed to the pyrolysis gas burner (34) and combusted there, and / or at least a part of the separated dusts and / or condensable substances can be fed to the reactor (6) via the reactor inlet (7).
8. Pyrolysis plants ( 1 ) according to any one of the preceding claims, wherein The cleaning conveying screw (17.2, 18.2) is designed as a hollow spiral screw, through whose center a cavity extends in the longitudinal direction, and the fixed bed cleaning (3) has a scraper chain which is attached to the two opposite ends of the hollow spiral screw at attachment points in such a way that it extends through the cavity of the hollow spiral screw and sags due to gravity to such an extent that it comes into contact with the hollow spiral screw at at least one further contact point between the two attachment points.
9. A method for producing a pyrolysis gas (30) and a pyrolysate (32) from a carbon-containing substrate (21) using a pyrolysis plant (1) according to one of the preceding claims, comprising the following steps: Filling the fixed bed cleaning unit (3) and the reactor (6) of the pyrolysis plant (1) with substrate (21) and conveying the substrate by means of the cleaning screw conveyor (17.2, 18.2) and the reactor screw conveyor (23.2, 24.2), 12953 / 1 / 2_WO Fixed bed cleaning by means of the pyrolysis gas line (28) discharge of the pyrolysis gas (30) from the reactor (6) in the area of the reactor outlet (8) and introduction of the pyrolysis gas (30) into the fixed bed cleaning system (3) in the area of the substrate outlet (5) of the fixed bed cleaning system (3), flow of the pyrolysis gas (30) through the fixed bed cleaning system (3) from the area of the substrate outlet (5) to the pyrolysis gas outlet (29) in the area of the substrate inlet (4), and Discharge of the pyrolysis gas ( 30 ) from the pyrolysis gas outlet ( 29 ).