Hydrogen generation pyrolysis system layout and associated operating procedure

Abstract

The invention relates to a hydrogen generation-pyrolysis system arrangement for the pyrolysis of hydrocarbon-containing substrates to hydrogen and carbon with individual discharge of the components formed. The arrangement comprises a furnace with a reactor, an inner wall, an outer wall, at least one substrate feed for adding a substrate, at least one first product discharge in the reactor head, at least one inert gas supply, at least one inert gas discharge, and at least one second product discharge in the reactor sump. Furthermore, the invention relates to an associated hydrogen generation pyrolysis system arrangement and operating method.

Description

[0001] The invention relates to a hydrogen production pyrolysis system arrangement comprising a furnace with a reactor, an inner wall, an outer wall, at least one substrate feed for adding a substrate, at least one first product discharge in the reactor head, at least one inert gas feed and at least one inert gas discharge, wherein the substrate comprises hydrocarbon compounds, the inner wall encloses the reactor, the outer wall encloses the furnace, the outer wall has the inert gas feed and the inert gas discharge, the temperature in the reactor is adjustable above 800 °C at atmospheric pressure and is adaptable accordingly in the event of a pressure change in the reactor and the reactor volume of the furnace comprises at least twice the resulting gas volume of the introduced substrate.

[0002] Furthermore, the invention relates to an associated hydrogen production pyrolysis system arrangement operating method.

[0003] Worldwide, ever-increasing amounts of hydrocarbon-containing waste are being produced, often stored in massive landfills. At the same time, people's environmental awareness is increasing, and fossil fuel reserves are declining. For these reasons, the possibility of generating energy through alternative energy sources by recycling hydrocarbon-containing waste, such as plastic waste, has come into focus. One option in this regard is the pyrolysis of hydrocarbon-containing waste, which harnesses previously unused energy potential while simultaneously reducing waste.

[0004] Pyrolysis is a well-known process in the art. Pyrolysis involves the thermochemical decomposition of organic, i.e., hydrocarbon-containing, compounds. Unlike combustion, the process takes place in the absence of oxygen and exclusively under the influence of heat. If oxygen-containing fuels, such as wood, are used, oxidation reactions also occur during the decomposition process.

[0005] Possibilities for carrying out pyrolysis to decompose hydrocarbon-containing waste have been developed for several decades and are also being applied in practice.

[0006] The applicant's publication DE 10 2020 104 763 B3 discloses a hydrogen pyrolysis system arrangement comprising a furnace with a reactor, an inner wall, an outer wall, at least one substrate feed for adding a substrate, at least one hydrogen feed for adding hydrogen, at least one product discharge, at least one inert gas feed and at least one inert gas discharge, wherein the substrate comprises carbon compounds, the inner wall encloses the reactor and the outer wall encloses the furnace, characterized in that the outer wall comprises the inert gas feed and the inert gas discharge, the substrate feed leads into the reactor in the form of a tube, the opening of which is located close to the reactor bottom, the hydrogen feed leads into the reactor in the form of a tube, the opening of which is located close to the reactor bottom,the temperature in the reactor is set above 800 °C at atmospheric pressure and is adjusted accordingly in the event of a pressure change in the reactor, complete decomposition of the substrate in the substrate feed occurs before flowing into the reactor due to the high reactor temperature, the product is discharged from the reactor in the form of a pipe whose opening is located just below the reactor lid, methane is formed in the lid section of the product discharge from carbon and hydrogen, and the reactor volume of the furnace comprises at least twice the resulting gas volume of the introduced substrate.

[0007] From the publication US 2013 / 0 172 637 A1 a process for converting biogenic waste into fuels such as methane and other hydrocarbons by means of hydropyrolysis at temperatures between 400°C and 550°C is known.

[0008] The document DE 696 24 073 T2 shows a process for treating waste, wherein the waste is pyrolyzed in a fluidized bed at high temperature to produce a combustible gas from a mixture of CO and H2.

[0009] The document DE 25 43 514 A1 shows a reaction apparatus for carrying out chemical reactions into which an inert fluid is introduced in order to form a protective layer around a reaction tube.

[0010] Furthermore, the document DE 44 46 964 C2 discloses a method and an apparatus for the pyrolytic decomposition of plastic waste and in particular a method by which a pyrolytic decomposition of waste plastic, including polyvinyl chloride resins and the like, can be effectively carried out to form a high-quality heating oil by pyrolysis of the waste plastic.

[0011] Document WO 2018 / 000050 A1 discloses a plant comprising a pyrolysis reactor configured to heat molten mixed plastic waste to produce pyrolysis gases at a first temperature of about 350°C to 425°C and pyrolysis slurry or pyrolysis char at a second temperature of 722°C to 1400°C.

[0012] The problems with the current state of the art are essentially that there are many approaches to decomposing hydrocarbon-containing substrates using pyrolysis, and just as many approaches to generating energy from hydrocarbon-containing substrates, for example, through combustion. A simple system for efficiently generating electrical energy and heat from a product from the pyrolysis of hydrocarbon-containing substrates, which can also be used for fuel production, is currently only known through the hydrogen pyrolysis system.

[0013] The present invention is based on the object of providing an arrangement based on the hydrogen pyrolysis system in which hydrogen is obtained from hydrocarbon-containing waste, in particular plastic, via pyrolysis for use in energy supply or fuel production and in which the resulting by-product can also be further processed.

[0014] This object is achieved with a hydrogen generation pyrolysis system arrangement according to the main claim and an associated hydrogen generation pyrolysis system arrangement operating method according to the independent claim.

[0015] The hydrogen generation pyrolysis system assembly comprises a furnace with: - a reactor; - an inner wall; - an outer wall; - at least one substrate feed for adding a substrate; - at least one first product discharge in the reactor head; - at least one inert gas supply and - at least one inert gas discharge; where - the substrate contains hydrocarbon compounds; - the inner wall encloses the reactor; - the outer wall encloses the oven; - the outer wall has the inert gas supply and the inert gas discharge; - the temperature in the reactor is adjustable above 800 °C at atmospheric pressure and can be adjusted accordingly in the event of a change in pressure in the reactor; - the reactor volume of the furnace comprises at least twice the resulting gas volume of the introduced substrate; and is characterized in that - at least one second product discharge is formed in the reactor sump; - the substrate feed is designed in the form of a filling tube with a temperature-stable first separating disc between the filling tube and the reactor leading into the reactor head; - the temperature in the substrate supply can be set below 50 °C; - the first separating disc is designed to be openable and closable at the transition between the filling tube and the reactor; - complete decomposition of the substrate after entry into the reactor is possible due to the high reactor temperature; - the product discharge in the reactor head is designed in the form of a pipe leading out of the reactor; - the product discharge in the reactor sump is designed in the form of an openable and closable temperature-stable double-pendulum flap with a subsequent product collection device leading out of the reactor, wherein the second double-pendulum flap separates the reactor from the product collection device and the second double-pendulum flap is arranged on the reactor sump; - the reactor is designed to have a dividing wall in the reactor interior, wherein the dividing wall is designed to run from the reactor head towards the reactor sump with an opening above the reactor sump parallel to the side walls of the reactor; - the partition wall is designed to divide the reactor interior into a flow zone and a calm zone; - the opening of the dividing wall above the reactor sump is designed as a connection between the flow-through and calm zones; where - only a low flow velocity can be developed in the calm zone; - the substrate supply is designed to lead into the flow zone; - the substrate is decomposable into carbon and hydrogen upon entering the flow zone; - the hydrogen formed can be removed through the product discharge located in the settled zone in the reactor head; - the carbon formed can be collected on the second double-pendulum flap of the product discharge in the reactor sump and discharged into the product collection device.

[0016] The substrate feed can be designed, in particular, as a feed for plastic. Because the substrate can be plastic, the hydrogen generation pyrolysis system arrangement according to the invention makes it possible to convert otherwise difficult-to-recycle plastic waste into hydrogen for further use, particularly for electricity generation and thermal energy.

[0017] In addition, the ceramic cutting disc can be designed with a pivoting closure and / or can be electrically driven, directly driven or driven via magnetic coupling and / or can be designed in particular to be openable and closable in a time of less than one second.

[0018] The separating disc made of a temperature-stable material separates the hot (900°C) reactor atmosphere from the “cold” atmosphere (40°C) in the filler neck.

[0019] Only the separation disc allows large quantities (> 500g to 5 kg) of granulate (e.g. plastic or sewage sludge) to fall freely through the filling nozzle into the reactor.

[0020] At a temperature of >100°C in the filler neck, all the granules would begin to decompose as they fell into the reactor. Part of the granules would adhere to the wall of the filler neck. This would cause the filler neck to become clogged within a short period of time.

[0021] In a preferred embodiment, the carbon formed in the product collection device can be cooled and / or the absorbed hydrogen can be exchanged for nitrogen and / or the carbon formed in the product collection device can be hydraulically pressed.

[0022] The area between the inner and outer walls of the furnace can be designed for continuous purging with an inert gas, such as air or nitrogen. In the event of a leak in the inner furnace wall, escaping hydrogen is detected by a hydrogen sensor. This triggers the flooding of the outer furnace with inert gas (e.g., nitrogen) before the oxyhydrogen limit is reached. This reliably prevents the risk of explosion.

[0023] The substrate is added in portions via the substrate feed, particularly with an opening and closing time of the separation disc of < 1 second. It is important to control the addition of substrate to the reactor in such a way that the temperature in the reactor is maintained so that decomposition of the substrate can take place as it is fed into the reactor. When feeding the substrate, the reactor volume of the furnace must be at least twice the gas volume generated by the introduced substrate to ensure homogeneous gas distribution. Hydrogen is continuously removed via the product discharge in the reactor head. The hydrogen in the cover section has a temperature of approximately 600 °C. This hydrogen can subsequently be stored for further use.

[0024] Carbon deposits on the second double-pendulum flap in the reactor sump after each substrate feed into the reactor. The carbon is removed in portions into the product collection device, particularly with an opening and closing time of the second double-pendulum flap of less than 1 second.

[0025] If the temperature in the reactor is 900 °C at atmospheric pressure, rapid decomposition of the hydrocarbon-containing substrate is achieved in the desired manner.

[0026] At temperatures above 800 °C, hydrogen is formed during the pyrolysis of a hydrocarbon-containing substrate.

[0027] The hydrogen generation pyrolysis system arrangement operating method with the hydrogen generation pyrolysis system arrangement comprises at least the following steps: - Feeding a substrate comprising hydrocarbon compounds via the feed pipe of the substrate feed by opening and closing the separating disc into the reactor to carry out a pyrolysis in the reactor with subsequent product separation, wherein - the temperature in the substrate supply is set below 50 °C; - the temperature in the reactor is set above 800 °C at atmospheric pressure and is adjusted accordingly if the pressure in the reactor changes; - Carrying out pyrolysis by decomposing the substrate into hydrogen and carbon upon entering the reactor due to the high reactor temperature; - Separation of hydrogen and carbon formed in the reactor, whereby - the mixture of hydrogen and carbon formed passes from the flow zone into the calm zone when passing through the opening of the partition wall; - the hydrogen formed in the settled zone rises into the reactor head and the carbon formed is accumulated on the second double-pendulum flap on the reactor sump; - Removal of the hydrogen formed through the product discharge in the reactor head; - Discharging the carbon formed on the second double pendulum flap from the reactor into the product collection device by opening and closing the second double pendulum flap.

[0028] In the operating method, the carbon may be cooled and filled in the product collection device, or the carbon may be cooled in the product collection device and absorbed hydrogen in the carbon may be exchanged for nitrogen, and / or the carbon may be hydraulically compressed and filled.

[0029] The hydrogen can be temporarily stored and / or used directly in other processes and / or flared.

[0030] The process waste heat can be used in other processes and / or to maintain the reactor temperature.

[0031] The outflow of substrate from the substrate feed into the reactor occurs in the flow-through zone at the reactor head. The inflow of hydrogen from the reactor into the product discharge occurs in the settled zone at the reactor head. The accumulation of carbon from the reactor into the product discharge occurs in the reactor sump on the second double-pendulum flap. These design measures are essential to ensure the desired function of the inventive arrangement—that is, the formation of hydrogen and carbon with subsequent recovery of the individual components formed through the decomposition of hydrocarbon-containing substrate.

[0032] Due to the reactor's design, as the product mixture of hydrogen and carbon rises in the settled zone at temperatures > 590 °C, the carbon separates and trickles downwards onto the second double-pendulum flap, while the hydrogen in the settled zone continues to flow upwards into the reactor head. This is due to the extremely slow flow velocity of the rising hydrogen combined with the effect of gravity.

[0033] The calm zone is created by a partition wall inside the reactor.

[0034] In particular, the carbon is removed, cooled, the absorbed hydrogen is exchanged for nitrogen and the product is bottled.

[0035] The invention is described below with reference to the accompanying figures in the description of the figures, which are intended to illustrate the invention and are not to be considered limiting. They show: Fig. an exemplary schematic representation of the structure of a hydrogen pyrolysis system arrangement according to the prior art; Fig. an exemplary schematic representation of the processes in the hydrogen generation pyrolysis system arrangement operating method in a hydrogen generation pyrolysis system arrangement; Fig. an exemplary schematic representation of a substrate supply of a hydrogen generation pyrolysis system arrangement ( Fig. with swivel lock ( Fig. ) and Fig. an exemplary schematic representation of a reactor section of a hydrogen production pyrolysis system arrangement.

[0036] Fig. shows an exemplary schematic representation of the structure of a hydrogen pyrolysis system arrangement 9 according to the prior art. A furnace 2 with an outer wall 21 and an inner wall 22 comprises a reactor 23. An inert gas supply 24 and an inert gas discharge 25 are located in the outer wall 21. A hydrogen sensor 251 is installed in the inert gas discharge 25 so that possible leaks in the reactor 23 can be detected. A substrate supply 26 and a hydrogen supply 27 lead into the interior of the reactor. The opening of the substrate supply 261 and the opening of the hydrogen supply 271 are located just above the reactor base 231. A product discharge 28 leads out of the reactor. The opening of the product discharge 281 is located just below the reactor cover 232. An inert gas 3 floods the area between the outer wall 21 and the inner wall 22 of the furnace 2 when hydrogen is detected.A substrate 4 is introduced into the reactor 23 via the substrate feed 26, and hydrogen 5 is introduced via the hydrogen feed 27. Hydrogen 5 and carbon leave the reactor 23 via the product discharge 28 and are converted into methane 6 within the reactor 23's cover section. The reactor 23 is maintained at an operating temperature of 900 °C. The methane that forms within the reactor's cover section in the product discharge 28 has a temperature below 600 °C.

[0037] In Fig. An exemplary schematic representation of the processes in the hydrogen generation pyrolysis system arrangement operating method in a hydrogen generation pyrolysis system arrangement 1 is shown. A substrate 4, in particular in the form of plastic, is fed via the substrate feed 26 into the reactor 23 in the region of the reactor head 232 in the flow-through zone 236. The substrate feed 26 comprises a double pendulum flap 260, an intermediate pipe 263, a metering valve 269, and a separating disk 262. In this example, the double pendulum flap 260 is operated with a vacuum pump 8. By briefly opening the double pendulum flap 260, the substrate 4 is fed portionwise into the metering valve 269. The double pendulum flap 260 preferably has an opening time and a closing time of less than 1 second.The temperature in the fill tube 263 is below 50°C, preferably approximately 40°C, and the temperature in the reactor 23 is above 800°C, both at atmospheric pressure. When the substrate 4 enters the reactor 23 by opening the first separating disk 262, it is decomposed into hydrogen 5 and carbon 7 due to the high reactor temperature. The hydrogen 5 and the carbon 7 formed flow in the reactor 23 along a dividing wall 233 located inside the reactor from the reactor head 232 in the direction of the reactor sump 231. The dividing wall 233 runs from the reactor head 232 in the direction of the reactor sump 231 with an opening 235 above the reactor sump 231 parallel to the side walls of the reactor 23. Via the opening in the dividing wall 235, the product in the area of ​​the reactor sump 231 passes from the flow-through zone 236 in the reactor 23 into the calmed zone 237 in the reactor 23. In the calmed zone 237 there is only a weak flow.Due to the reactor design in combination with gravity, this causes the carbon 7 in the reactor 23 to trickle down and collect in the reactor sump 231 on a double-pendulum flap 234. In this example, the double-pendulum flap is operated by a vacuum pump 8. The accumulated carbon 7 is discharged in portions into the product collection device 291 by briefly opening and closing the double-pendulum flap 234. The double-pendulum flap preferably has an opening and closing time of less than 1 second. The hydrogen 5 formed flows into the reactor head 232 and to the product discharge in the reactor head 28 and is, in particular, continuously discharged from the reactor 23. The hydrogen 5 has a temperature of below 600 °C within the cover section of the reactor in the product discharge 28, so that atomic hydrogen present after the substrate decomposition is converted to molecular hydrogen.

[0038] The hydrogen 5 produced can be temporarily stored and / or used directly in other processes and / or flared. Preferably, the hydrogen 5 produced is compressed to a pressure of 10 bar with a compressor upon leaving the system 1. One possible application for the hydrogen 5 is, for example, its use in combined heat and power plants or generally in combined heat and power plants.

[0039] The extracted carbon 7 can be used in the manufacture of products such as steel, aluminum, bitumen, tires, and dyes. Using carbon 7 in this area can avoid significant amounts of imports of soot and coking coal.

[0040] The process waste heat 10 occurring in both product discharges 28, 29 can be used in other processes and / or to maintain the reactor temperature in the hydrogen production pyrolysis system arrangement 1 according to the invention.

[0041] A throughput of, for example, 1000 kg of substrate can be easily implemented with the arrangement 1 according to the invention if the arrangement 1 is dimensioned accordingly.

[0042] Fig. shows an exemplary schematic representation of a substrate feed 26 of a hydrogen generation pyrolysis system arrangement 1 ( Fig. with cutting disc 262 and swivel lock 2621 ( Fig. ). In the Fig. The filling tube 263 is shown connected to the cutting disc 262. The cutting disc 262 is equipped with a drive 2622. Fig. shows the cutting disc with swivel lock 2621 from below in the closed form and Fig. in the opened form.

[0043] In addition, Fig. an exemplary schematic representation of a reactor section of a hydrogen production pyrolysis system arrangement 1. The reactor 23 with reactor head 232 and reactor sump 231 and the internal partition wall 233 as well as the opening of the substrate feed 261, the opening of the product discharge in the reactor head 281 and the opening of the product discharge in the reactor sump 292 are shown.

[0044] The substrate 4 passes through the substrate feed 26 via the opening of the substrate feed 261 (separating disc 262 not shown here) into the reactor 23. The processes follow as already described in the description of Fig. The hydrogen 5 formed leaves the reactor 23 via the product discharge opening in the reactor head 281, and the carbon 7 formed leaves the reactor 23 via the product discharge opening in the reactor bottom 292 (double-pendulum flap 234 not shown here). List of reference symbols 1 Hydrogen production pyrolysis system arrangement 2 ovens 21 outer wall 22 inner wall 23 reactor 231 reactor sump 232 reactor head 233 Partition wall 234 second double-pendulum flap 235 Opening partition wall 236 flow zones 237 calm zone 24 Inert gas supply 25 Inert gas removal 251 Hydrogen sensor inert gas removal 26 Substrate supply 260 first double-pendulum flap 261 Substrate supply opening 262 cutting disc 2621 swivel lock 2622 Drive connection 263 Filling tube 269 ​​Dosing valve 27 Hydrogen supply 271 Opening hydrogen supply 28 Product discharge reactor head 281 Opening product discharge reactor head 29 Product discharge reactor sump 291 Product collection device 292 Opening product discharge reactor sump 3 Inert gas 4 Substrat 5 Hydrogen 6 Methane 7 Carbon 8 Pump, vacuum pump 9 Hydrogen pyrolysis system arrangement 10 Waste heat, process waste heat

Claims

[1] Hydrogen production pyrolysis system arrangement (1) comprising a furnace (2) with: - a reactor (23); - an inner wall (22); - an outer wall (21); - at least one substrate feed (26) for adding a substrate (4); - at least one first product discharge in the reactor head (28); - at least one inert gas supply (24) and - at least one inert gas discharge (25); where - the substrate (4) comprises hydrocarbon compounds; - the inner wall (22) encloses the reactor (23); - the outer wall (21) encloses the furnace (2); - the outer wall (21) has the inert gas supply (24) and the inert gas discharge (25), - the temperature in the reactor (23) is adjustable above 800 °C at atmospheric pressure and can be adjusted accordingly in the event of a pressure change in the reactor (23), - the reactor volume of the furnace (2) is at least twice the resulting gas volume of the introduced substrate (4), characterized by , that - at least one second product discharge is formed in the reactor sump (29); - the substrate feed (26) is designed in the form of a filling tube (263) with a temperature-stable separating disc (262) between the filling tube (263) and the reactor (23) leading into the reactor head (232), - the temperature in the substrate feed (26) can be set below 50 °C, - the separating disc (262) is designed to be openable and closable at the transition between the filling tube (263) and the reactor (23), - a complete decomposition of the substrate (4) after entry into the reactor (23) is possible due to the high reactor temperature, - the product discharge in the reactor head (28) is designed in the form of a pipe leading out of the reactor (23), - the product discharge in the reactor sump (29) is designed in the form of an openable and closable temperature-stable double-pendulum flap (234) with a subsequent product collection device (291) leading from the reactor (23), wherein the double-pendulum flap (234) separates the reactor (23) from the product collection device (291) and the double-pendulum flap (234) is arranged on the reactor sump (231), - the reactor (23) is designed to have a partition wall (233) in the reactor interior, wherein the partition wall (233) is designed to run from the reactor head (232) towards the reactor sump (231) with an opening (235) above the reactor sump (231) parallel to the side walls of the reactor (23), - the partition wall (233) is designed to divide the reactor interior into a flow zone (236) and a calm zone (237), - the opening of the partition wall (235) above the reactor sump (231) is designed as a connection between the flow-through zone (236) and the calm zone (237), where - only a low flow velocity can be formed in the calm zone (237), - the substrate supply (26) is designed to lead into the flow-through zone (236), - the substrate (4) is decomposable into carbon (7) and hydrogen (5) upon entering the flow zone (236), - the hydrogen (5) formed can be discharged through the product discharge in the reactor head (28) located in the calmed zone (237); - the carbon (7) formed can be collected on the double pendulum flap (234) of the product discharge (29) in the reactor sump (231) and discharged into the product collection device (291). [2] Arrangement (1) according to claim 1 characterized by that the substrate feed (26) is designed as a feed for plastic. [3] Arrangement (1) according to claim 1 or 2 characterized by that the first cutting disc (262) - made of ceramic and / or - is designed with a swivel lock (2621) and / or - electrically, directly driven or driven via magnetic coupling and / or - can be opened and closed in less than one second. [4] Arrangement (1) according to one of the preceding claims, characterized by , that - the carbon (7) formed can be cooled in the product collection device (291) and / or - the absorbed hydrogen (5) is designed to be exchangeable for nitrogen and / or - the carbon (7) formed can be hydraulically pressed in the product collecting device (291). [5] Hydrogen generation pyrolysis system arrangement operating method with the hydrogen generation pyrolysis system arrangement (1) according to one of claims 1 to 4 comprising at least the steps: - feeding a substrate (4) comprising hydrocarbon compounds via the filling pipe (263) of the substrate feed (26) by opening and closing the separating disc (262) into the reactor (23) to carry out a pyrolysis in the reactor (23) with subsequent product separation, wherein - the temperature in the substrate feed (26) is set below 50 °C, - the temperature in the reactor (23) is set above 800 °C at atmospheric pressure and is adjusted accordingly in the event of a pressure change in the reactor (23), - carrying out the pyrolysis by decomposing the substrate (4) upon entry into the reactor (23) into hydrogen (5) and carbon (7) due to the high reactor temperature, - Separating the hydrogen (5) and carbon (7) formed in the reactor (23), whereby - the mixture formed of hydrogen (5) and carbon (7) passes from the flow-through zone (236) into the calm zone (237) when passing through the opening of the partition wall (235), - the hydrogen (5) formed in the calmed zone (237) rises into the reactor head (28) and the carbon (7) formed is collected on the second double-pendulum flap (234) on the reactor sump (231), - removal of the hydrogen formed (5) through the product discharge in the reactor head (232), - Discharging the carbon (7) formed on the double pendulum flap (234) from the reactor (23) into the product collection device (291) by opening and closing the double pendulum flap (234). [6] Operating method according to the preceding claim, characterized by , that - the carbon (7) is cooled and filled in the product collection device (291), - the carbon (7) is cooled in the product collection device (291) and absorbed hydrogen (5) is exchanged for nitrogen and / or is hydraulically pressed and filled, - the hydrogen (5) is temporarily stored and / or used directly in other processes and / or flared, - the process waste heat (10) is used in other processes and / or to maintain the reactor temperature.

Images