Pyrolysis plant and method for thermal mineralization of biomass and production of combustible gases, liquids and biochar
Patent Information
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- Filing Date
- 2026-02-04
- Publication Date
- 2026-08-13
Smart Images
Figure DK2026060010_13082026_PF_FP_ABST
Abstract
Description
[0001] Pyrolysis plant and method for thermal mineralization of biomass and production of combustible gases, liquids and biochar
[0002] Field of invention
[0003] The present invention relates to a pyrolysis plant and a method for thermal mineralization of biomass and production of combustible gases, liquids and biochar.
[0004] Prior art
[0005] Pyrolysis is a well-known process, which is used for converting organic materials into energy in the form of gas. Many methods and reactor designs have been developed over the course of time.
[0006] Pyrolysis makes it possible to convert biomass such as straw, farmyard manure, energy crops or organic residues to a gas, which can be used for example in a combined heat and power station. The ash (biochar) from the process is rich in nutrient that are required for growth and development of crops.
[0007] In a typical pyrolysis plant, comminuted biomass is fed into a pyrolysis chamber, which is heated in the absence of oxygen. As no oxygen is present, the biomass does not burn. Instead, the biomass is converted to approx. 80% pyrolysis gas and 20% coke (carbon). Sand particles are injected from the bottom of the pyrolysis chamber, for the purpose of swirling the coke particles and entraining them out of the pyrolysis chamber. The pyrolysis gas formed and the coke are withdrawn from the upper part of the pyrolysis chamber and transferred to a first cyclone, where the sand and coke particles are separated and go down into a coke reactor, while the pyrolysis gases are transferred to another cyclone, where the ash, which contains nutrient salts, is separated and is transferred to a container. The gases leaving the other cyclone cannow be used in for example combined heat and power stations.
[0008] The coke reactor is configured for gasifying the coke. The gas is led to the pyrolysis chamber. Air is fed into the coke reactor.
[0009] In a prior art pyrolysis apparatus for rapid conversion of petrochemicalbased waste to gas and liquid fuel, biomass is sent through an externally reaction channel consisting of one or more tubes. The tubes are arranged and configured to be heated via heat transfer between the walls of the tubes and one or more adjacent heating circuits. Accordingly, the thickness of the walls separating the tubes and one or more adjacent heating circuits. It has been experimentally observed that the rate of heat conduction through a layer is proportional to the temperature difference across the layer and the heat transfer area, but it is inversely proportional to the thickness of the layer. Accordingly, the thickness of the walls is a main determinant of the rate of heat conduction.
[0010] Since the rate of heat conduction determines how fast heat can be transferred to the biomass in the reaction channel, it is a disadvantage to apply thick walls.
[0011] It is desirable to increase the speed, by which heat can be transferred to the biomass in the heated vessel. Thus, it is an object of the present invention to provide a pyrolysis plant for thermal mineralization of biomass and production of combustible gases, liquids and biochar, in which pyrolysis plant the speed, by which heat can be transferred to the biomass in the reaction channel can be increased. It is also an object to provide a method for thermal mineralization of biomass and production of combustible gases, liquids and biochar, which method allows for increasing the speed, by which heat can be transferred to the biomass in the reaction channel.US20130195727A1 discloses a fluidized bed biogasifier for gasifying biosolids. The biogasifier includes a reactor vessel and a feeder for feeding biosolids into the reactor vessel at a desired feed rate during steady-state operation of the biogasifier. A fluidized bed in the base of the reactor vessel has a cross-sectional area that is proportional to at least the fuel feed rate such that the superficial velocity of gas is in the range of 0.1 m / s to 3 m / s. The temperature within the gasifier is controlled by introducing ambient air. The oxygen in the ambient air is hereby used to heat the reactor vessel. By introducing ambient air into the gasifier, a large quantity of Nitrogen gas (N2) enters the gasifier. This is a huge disadvantage because the N2would have to be removed from the pyrolysis gas. Accordingly, in some applications it would be desirable to have an alternative solution.
[0012] US 20230195727 Al discloses a fluidized bed biogasifier for gasifying biosolids. The biogasifier includes a reactor vessel and a feeder for feeding biosolids into the reactor vessel at a desired feed rate during steady-state operation of the biogasifier. A fluidized bed in the base of the reactor vessel has a cross-sectional area that is proportional to at least the fuel feed rate such that the superficial velocity of gas is in the range of 0.1 m / s (0.33 ft / s) to 3 m / s (9.84 ft / s). In a method for gasifying biosolids, biosolids are fed into a fluidized bed reactor. Oxidant gases are applied to the fluidized bed reactor to produce a superficial velocity of producer gas in the range of 0.1 m / s (0.33 ft / s) to 3 m / s (9.84 ft / s). The biosolids are heated inside the fluidized bed reactor to a temperature range between 900° F. (482.2° C.) and 1700° F. (926.7° C.) in an oxygen-starved environment having a sub-stoichiometric oxygen level, whereby the biosolids are gasified. It would be desirable to be able to increase the efficiency of the system.
[0013] US 20130025200 Al discloses a gasifier system for converting biomass to biogas. The system comprises a reaction chamber with a biomasssupply port for receiving a biomass volume, a waste outlet port for discharging biomass conversion by-products, a gas inlet for receiving heated oxidizing gas, a gas outlet for discharging generated biogas and a burner manifold for distributing oxidizing gas within the chamber to react the biomass. The burner manifold includes primary tubes and secondary tubes, positioned in a vertically lower part of the chamber and configured with multiple openings or ports for dispensing the oxidizing gas, where the secondary tubes extend into, inject and evenly distribute the oxidizing gas into the biomass volume to optimize conversion to biogas. It would be desirable to be able to increase the efficiency of the system.
[0014] US20230287285A1 discloses a method and a pyrolysis plant comprising a reactor for producing pyrolysis gas from biomass. The reactor comprise one or more reaction channels linked thermally with at least one heating circuit, which is configured to heat the reaction channels to a temperature that is high enough to gasify the biomass. The reactors comprise a feed section configured for feeding the biomass into the reaction channels. The pyrolysis plants comprise a gas accelerator configured for recirculating the gas that is present in the at least one reaction channel and for providing a gas flow velocity that is able to distribute the biomass in the reaction channel.
[0015] In the prior art biogasifier systems a blower configured to provide a gas flow in the reaction channel is mandatory. Accordingly, without a blower configured to provide a gas flow in the reaction channel, the system would not work. The use of a blower is, however, associated to several drawbacks. First of all, driving a blower increases the energy consumption of the system and this provides a lower efficiency. Moreover, due to the high temperatures, the blower needs to be customised to resist the extreme conditions. Accordingly, the cost of the blower would typically be very high.It is an object of the invention to increase the efficiency of a pyrolysis plant.
[0016] Summary of the invention
[0017] The object of the present invention can be achieved by a pyrolysis plant as defined in claim 1 and by a method as defined in claim 13. Preferred embodiments are defined in the dependent subclaims, explained in the following description and illustrated in the accompanying drawings.
[0018] The pyrolysis plant according to the invention is a pyrolysis plant comprising a reactor for producing pyrolysis gas from biomass, wherein the reactor comprises at least one reaction channel configured to circulate the pyrolysis gas generated in the reaction channel, wherein the reaction channel:
[0019] a) has at least one integrated heating circuit configured to heat the at least one reaction channel to a temperature that is high enough to gasify the biomass and
[0020] b) is configured to generate a sufficiently large flow of the produced pyrolysis gas to carry the biochar generated in the reaction channel, wherein the pyrolysis plant comprises a feed section configured for feeding the biomass into the at least one reaction channel,
[0021] wherein the pyrolysis plant comprises:
[0022] one or more flow sensors arranged and configured to detect the flow in the at least one reaction channel and
[0023] a control unit arranged and configured to control the flow in the at least one reaction channel by regulating the velocity at which biomass is feed into the at least one reaction channel,
[0024] wherein the pyrolysis plant is configured to be operated without using any blower when the at least one reaction channel has been heated to the temperature that is high enough to gasify the biomass.Hereby, it is possible to:
[0025] a) provide an alternative solution, in which the no blower configured to provide a gas flow in the reaction channel is mandatory when the at least one reaction channel has been heated to the temperature that is high enough to gasify the biomass,
[0026] b) increase the efficiency of a pyrolysis plant because the need for flow generating blowers or fans can be eliminated during operation of the pyrolysis plant (when the at least one reaction channel has been heated to the temperature that is high enough to gasify the biomass).
[0027] The invention overcomes the technical prejudice "that in biogasifier systems a blower configured to provide a gas flow in the reaction channel is mandatory".
[0028] In an embodiment, the reaction channel has a single integrated heating circuit configured to heat the at least one reaction channel to a temperature that is high enough to gasify the biomass.
[0029] In an embodiment, the reaction channel has two or more integrated heating circuits configured to heat the at least one reaction channel to a temperature that is high enough to gasify the biomass.
[0030] The reaction channel is configured to generate a sufficiently large flow of the produced pyrolysis gas to carry the biochar generated in the reaction channel. Hereby, the use of electrically powered blowers can be eliminated.
[0031] The pyrolysis plant comprises a feed section configured for feeding the biomass into the at least one reaction channel.
[0032] In an embodiment, the pyrolysis plant comprises a single flow sensorarranged and configured to detect the flow in the at least one reaction channel.
[0033] In an embodiment, the pyrolysis plant comprises two or more flow sensors arranged and configured to detect the flow in the at least one reaction channel.
[0034] The pyrolysis plant comprises a control unit arranged and configured to control the flow in the at least one reaction channel by regulating the velocity at which biomass is feed into the at least one reaction channel.
[0035] In an embodiment, the pyrolysis plant comprises a blower arranged to increase the flow, wherein the control unit is communicatively connected to and configured to control the blower. The blower is intended for being used only when the pyrolysis plant is being started up. Accordingly, the flow of the produced gas is sufficient to carry the biochar.
[0036] The pyrolysis plant is configured to be operated without using any blower when the at least one reaction channel has been heated to the temperature that is high enough to gasify the biomass. This can be done by controlling the flow in the reaction channel by regulating the velocity at which biomass is feed into the reaction channel. The flow in the reaction channel can be increased by increasing the velocity at which biomass is feed into the reaction channel. The flow in the reaction channel can be decreased by decreasing the velocity at which biomass is feed into the reaction channel.
[0037] The one or more flow sensors arranged and configured to detect the flow in the at least one reaction channel makes it possible to monitor the flow in the at least one reaction channel and hereby increase or decrease the flow by increasing or decreasing the velocity at whichbiomass is feed into the at least one reaction channel.
[0038] In an embodiment, the flow in the reaction channel is regulated by applying an On-Off control mechanism that works by increasing or decreasing the flow based on its relationship to predefined upper and lower limits. When the flow exceeds the upper limit, the control mechanism decreases the flow. When the flow falls to or below the lower limit, the control mechanism increases the flow.
[0039] In an embodiment, the blower arranged in the reaction channel.
[0040] In an embodiment, the heating circuit is configured to receive and combust a combustion gas, preferably pyrolysis produced by the pyrolysis plant, wherein the heating circuit and the at least one reaction channel are not in fluid communication, wherein at least a portion of the heating circuit is provided and extends inside the at least one reaction channel.
[0041] In an embodiment, the reaction channel comprises a vertically arranged section, wherein the integrated heating circuit is arranged in the vertically arranged section, wherein the vertically arranged section is at least 5 m.
[0042] In an embodiment, the vertically arranged section is at least 6 m.
[0043] In an embodiment, the vertically arranged section is at least 8 m.
[0044] In an embodiment, the vertically arranged section is at least 10 m.
[0045] In an embodiment, the reaction channel comprises a first conduit that is in connected to a bottom portion of the vertically arranged section, wherein the reaction channel comprises a second conduit that is in connected to a top portion of the vertically arranged section, wherein the first conduit and the second conduit are in fluid communication witheach other.
[0046] In an embodiment, the first conduit is directly connected to the second conduit.
[0047] In an embodiment, the first conduit is directly connected to a cyclone that is connected to the second conduit, wherein the cyclone is arranged and configured to remove biochar from the reaction channel by guiding biochar through an outlet structure, wherein the cyclone is arranged and configured to remove biochar from the first conduit.
[0048] In an embodiment, the cyclone is arranged at an end portion of the first conduit of the reaction channel. Hereby, the majority (if not all of) the biochar will be collected before being transported via the second conduit.
[0049] In an embodiment, the cyclone comprises an outlet structure provided with a biochar outlet. The outlet structure is provided with a gas inlet for a flowing gas needed to drive the cyclone.
[0050] In an embodiment, the pyrolysis plant comprises a combustion air inlet pipe configured to introduce combustion air into the reaction channel, wherein the reaction channel constitutes the heating circuit.
[0051] In an embodiment, the combustion air is a predefined mix of O2 and inactive gas. In an embodiment, the combustion air is a predefined mix of O2 and CO2. In an embodiment, the combustion air is a predefined mix of O2 and steam. In an embodiment, the combustion air is atmospheric air. In an embodiment, the combustion air is atmospheric air and steam.
[0052] In an embodiment, the pyrolysis plant comprises a feed sectiondesigned for feeding comminuted biomass into the reaction channel, wherein the feed section comprises or is connected to a sluice configured to limit the quantity of oxygen that enters the reactor so that the comminuted biomass is fed into the reaction channel in a manner that reduces the amount of oxygen entering the reactor together with the biomass.
[0053] In an embodiment, the sluice is a rotary wheel sluice.
[0054] In an embodiment, the feed section comprises a gravity feeder.
[0055] In an embodiment, the pyrolysis plant comprises a biomass intake section having a tubular form, wherein the biomass intake section extends between the sluice and the reaction channel.
[0056] In an embodiment, the pyrolysis plant comprises one or more nonreturn valves arranged in the reaction channel.
[0057] In an embodiment, several non-return valves are arranged in the reaction channel to ensure a uniform direction of the flow. Moreover, it enables that the velocity at which biomass is feed into the reaction channel can be used to regulate the flow.
[0058] In an embodiment, the pyrolysis plant comprises a feed section that comprises a conduit through which comminuted biomass enters the feed section, wherein the feed section comprises a ring-shaped guide structure configured to circulate air and comminuted biomass to provide a uniform flow distribution of comminuted biomass, wherein a blower is arranged in the conduit, said blower being arranged and configured to generate an air flow capable of:
[0059] - sucking comminuted biomass from the conduit into the guide structure and- circulating the comminuted biomass in the conduit, wherein the guide structure is arranged and configured to feed the sluice.
[0060] Thus, a steady flow of comminuted biomass can be filled into the rotary wheel sluice. Accordingly, it is possible to achieve a steady velocity at which comminuted biomass is feed into the reaction channel of the pyrolysis plant.
[0061] In an embodiment, the pyrolysis plant is configured to ensure that the pressure P2 inside the reaction channel exceed the pressure Pi in the guide structure. Hereby, it is possible to further limit the flow of oxygen from the guide structure to the reaction channel via the sluice.
[0062] In an embodiment, the at least one pressure sensor is arranged to detect the pressure Pi in the guide structure and at least one pressure sensor is arranged to detect the pressure P2 in the reaction channel. Hereby, it is possible to monitor the pressure Pi in the guide structure and the pressure P2 in the reaction channel.
[0063] In an embodiment, the pyrolysis plant comprises a control unit configured to regulate the pressure P2 in the reaction channel. This may be done by regulating the velocity at which biomass is feed into the reaction channel.
[0064] In an embodiment, the pyrolysis plant comprises a control unit configured to regulate the pressure Pi in the guide structure. This may be done by regulating the speed of the blower.
[0065] The method according to the invention is a m method for producing pyrolysis gas from biomass by using a pyrolysis plant comprising a reactor for producing pyrolysis gas from biomass, wherein the reactorcomprises at least one reaction channel configured to circulate the pyrolysis gas generated in the reaction channel, wherein the reaction channel:
[0066] a) has at least one integrated heating circuit configured to heat the at least one reaction channel to a temperature that is high enough to gasify the biomass and
[0067] b) is configured to generate a sufficiently large flow of produced pyrolysis gas to carry the biochar in the reaction channel,
[0068] wherein the pyrolysis plant comprises a feed section configured for feeding the biomass into the at least one reaction channel,
[0069] wherein the method comprising:
[0070] detecting the flow in the at least one reaction channel by using one or more flow sensors and
[0071] by using a control unit controlling the flow in the at least one reaction channel by regulating the velocity at which biomass is feed into the at least one reaction channel.
[0072] In an embodiment, the method comprising:
[0073] - during starting up the pyrolysis plant, by using the control unit being communicatively connected to and configured to control a blower applying said blower to generate a flow in the at least one reaction channel.
[0074] In an embodiment, the method, comprising:
[0075] - applying a heating circuit configured to receive and combust a combustion gas, preferably pyrolysis produced by the pyrolysis plant to generate heat, wherein the heating circuit and the at least one reaction channel are not in fluid communication, wherein at least a portion of the heating circuit is provided and extends inside the at least one reaction channel.
[0076] In an embodiment, the method comprising:
[0077] applying a reaction channel comprising a vertically arranged section,wherein the integrated heating circuit is arranged in the vertically arranged section, wherein the vertically arranged section is at least 5 m.
[0078] In an embodiment, the method comprising:
[0079] - feeding comminuted biomass into the reaction channel by using a feed section comprising or being connected to a sluice configured to limit the quantity of oxygen that enters the reactor so that the comminuted biomass is fed into the reaction channel in a manner that reduces the amount of oxygen entering the reactor together with the biomass.
[0080] In an embodiment, the sluice is a rotary wheel sluice. In an embodiment, the feed section comprises a gravity feeder.
[0081] In an embodiment, the method comprising:
[0082] applying one or more non-return valves arranged in the reaction channel to ensure a uniform direction of the flow.
[0083] In an embodiment, several non-return valves are arranged in the reaction channel to ensure a uniform direction of the flow Moreover, it enables that the velocity at which biomass is feed into the reaction channel can be used to regulate the flow.
[0084] In an embodiment, the method comprising:
[0085] applying a feed section to feed biomass into the sluice, wherein the feed section comprises a conduit through which comminuted biomass enters the feed section to feed, wherein the feed section comprises a ringshaped guide structure configured to recirculate air and comminuted biomass to provide a uniform flow distribution of comminuted biomass, wherein a blower is arranged in the conduit, said blower being arranged and configured to generate an air flow capable of:
[0086] - sucking comminuted biomass from the conduit into the guidestructure and
[0087] - circulating the comminuted biomass in the conduit,
[0088] wherein the guide structure is arranged and configured to feed the sluice.
[0089] Thus, a steady flow of comminuted biomass will be filled into the rotary wheel sluice. Accordingly, it is possible to achieve a steady velocity at which comminuted biomass s feed into the reaction channel of the pyrolysis plant.
[0090] In an embodiment, the method comprises the step of
[0091] ensuring that the pressure P2 inside the reaction channel exceed the pressure Pi in the guide structure by using:
[0092] at least one pressure sensor arranged to detect the pressure Pi in the guide structure and
[0093] at least one pressure sensor is arranged to detect the pressure P2 in the reaction channel.
[0094] Hereby, it is possible to further limit the flow of oxygen (O2) from the guide structure to the reaction channel via the sluice. In an embodiment
[0095] Hereby, it is possible to monitor the pressure Pi in the guide structure and the pressure P2 in the reaction channel.
[0096] In an embodiment, the method comprises the step of a control unit configured to regulate the pressure P2 in the reaction channel. This may be done by regulating the velocity at which biomass is feed into the reaction channel.
[0097] In an embodiment, the method comprises the step of applying a control unit configured to regulate the pressure Pi in the guide structure. This may be done by regulating the speed of the blower.Description of the Drawings
[0098] The invention will become more fully understood from the detailed description given herein below. The accompanying drawings are given by way of illustration only, and thus, they are not limitative of the present invention. In the accompanying drawings:
[0099] Fig. 1A shows a schematic view of a pyrolysis plant according to the invention;
[0100] Fig. IB shows a schematic view of a pyrolysis plant according to the invention;
[0101] Fig. 2A shows a schematic view of a pyrolysis plant according to the invention;
[0102] Fig. 2B shows a schematic view of a pyrolysis plant according to the invention;
[0103] Fig. 3 shows a flowchart illustrating main principles of the method according to the invention;
[0104] Fig. 4A shows a schematic view of a pyrolysis plant according to the invention;
[0105] Fig. 4B shows a schematic view of a feed section of a pyrolysis plant according to the invention;
[0106] Fig. 5A shows a schematic view of a pyrolysis plant according to the invention and
[0107] Fig. 5B shows a close-up view of a portion of the pyrolysis plant shown in Fig 5A.
[0108] Detailed description of the invention
[0109] Referring now in detail to the drawings for the purpose of illustrating preferred embodiments of the present invention, a pyrolysis plant 2 of the present invention is illustrated in Fig. 1A.
[0110] Fig. 1A illustrates a schematic view of a pyrolysis plant 2 according to the invention. The pyrolysis plant 2 comprises a reactor 3 for producingpyrolysis gas 28 from biomass 30. The reactor 3 comprises a reaction channel 4 that has an integrated heating circuit 18 configured to heat the reaction channel 4 to a temperature that is high enough to gasify the biomass 30. The biomass 30 will typically be comminuted.
[0111] The pyrolysis plant 2 comprises a feed section 6 configured for feeding the biomass 30 into the reaction channel 4. The biomass 30 enters the feed section 6 and passes through a sluice 7. The sluice 7 is configured to limit the quantity of oxygen that enters the reactor 3. Accordingly, the comminuted biomass is fed into the reaction channel 4 in a manner the minimizes the amount of oxygen entering the reactor 3 together with the biomass 30. In an embodiment, the sluice 7 is a rotary wheel sluice.
[0112] In an embodiment, the feed section 6 comprises a gravity feeder.
[0113] The reaction channel 4 is configured to generate a sufficiently large flow Q of produced pyrolysis gas 28 to carry the biochar 42 in the reaction channel 4. In order to introduce a one-way flow Q, one or more nonreturn valves may be arranged in the reaction channel 4. In an embodiment, however, no non-return valves are used. The flow direction is indicated. The disclosure enables that the velocity at which biomass 30 is feed into the reaction channel 4 can be used to regulate the flow Q.
[0114] If a higher flow Q is required, the velocity at which biomass 30 is feed into the reaction channel 4 is increased. On the other hand, if a lower flow Q is required, the velocity at which biomass 30 is feed into the reaction channel 4 is decreased. If the flow Q is at a desired level, the velocity at which biomass 30 is feed into the reaction channel 4 is maintained.The pyrolysis plant 2 comprises at least one flow sensor 9 arranged and configured to detect the flow Q. The at least one flow sensor 9 is typically arranged in the reaction channel 4.
[0115] In an embodiment, a single flow sensor 9 is arranged in the reaction channel 4. In an embodiment, two or more flow sensors 9 are arranged in the reaction channel 4.
[0116] The pyrolysis plant 2 comprises a control unit 12 arranged and configured to control the flow Q in the reaction channel 4. The control unit 12 connected to the feed section 6 and control the velocity at which biomass 30 is feed into the reaction channel 4.
[0117] In an embodiment, the feed section 6 comprises a screw feeder (not shown). In this embodiment the control unit 12 can control the speed of the screw feeder and thus control the velocity at which biomass 30 is feed into the reaction channel 4.
[0118] In an embodiment, the feed section 6 comprises an air flow generator (not shown) arranged and configured to generate an air flow capable of distributing biomass 30 to the sluice 7. In this embodiment, the control unit 12 can control the speed of the air flow generator and thus control the velocity at which biomass 30 is feed into the reaction channel 4. The air flow generator may comprise a fan (e.g. an electrically controlled fan).
[0119] The reaction channel 4 comprises a vertically arranged section 50, in which the integrated heating circuit 18 is arranged. The reaction channel 4 comprises a first conduit 22 that is in connected to the bottom portion of the vertically arranged section of the reaction channel 4. The reaction channel 4 comprises a second conduit 22' that is in connected to the top portion of the vertically arranged section of thereaction channel 4. The first conduit 22 and the second conduit 22' are in fluid communication with each other. In an embodiment, the first conduit 22 is directly connected to the second conduit 22'. In an embodiment, the first conduit 22 is directly connected to a cyclone 24 that is connected to the second conduit 22'.
[0120] The cyclone 24 is arranged and configured to remove biochar 42 from the reaction channel 4. In an embodiment, the cyclone 24 is arranged and configured to remove biochar 42 from the first conduit 22 of the reaction channel 4.
[0121] In an embodiment, the cyclone 24 is arranged at an end portion of the first conduit 22 of the reaction channel 4. Hereby, the majority (if not all of) the biochar 42 will be collected before being transported upwards via the second conduit 22'.
[0122] The cyclone 24 comprises an outlet structure provided with a biochar outlet 21. The outlet structure is provided with a gas inlet 19. The flowing gas needed to drive the cyclone 24 is guided via the gas inlet 19. The flowing gas is released through the biochar outlet 21.
[0123] The second conduit 22' is connected to a gas cleaning unit 26 that is configured to clean the pyrolysis gas 28 generated in the reaction channel 4. The gas cleaning unit 26 comprises a pyrolysis gas outlet 23, by which cleaned pyrolysis gas can be evacuated.
[0124] The gas cleaning unit 26 comprises a waste outlet 25 for waste oil. The gas cleaning unit 26 comprises a heat outlet 27. The heat outlet may comprise a media circulated inside the gas cleaning unit 26 to allow heat exchange between the pyrolysis gas inside the gas cleaning unit 26 and the media being circulated.Fig. IB illustrates a schematic view of a pyrolysis plant 2 according to the invention. The pyrolysis plant 2 basically corresponds to the one shown in and explained with reference to Fig. 1A. The second conduit 22' is, however, connected to the vertically arranged section 50 so that produced pyrolysis gas 28 is being recirculated. The pyrolysis plant 2 comprises a blower 15 arranged to generate a and / or increase the flow in the reaction channel 4. In an embodiment, the blower 15 is arranged in the second conduit 22'. In an embodiment, the blower 15 is arranged in the first conduit 22.
[0125] The blower 15 can be used during start-up of the pyrolysis plant 2. During operation of the pyrolysis plant 2, however, the blower 15 would typically not be needed.
[0126] The control unit 12 is communicatively connected to the blower 15. Accordingly, the control unit 12 can regulate the activity of the blower 15, including turning on the blower 15, turning off the blower 15 and regulating and changing the speed of the bower 15.
[0127] In order to introduce a one-way flow Q, a non-return valve 17 is arranged in the reaction channel 4. The non-return valve 17 is placed in the second conduit 22' after the blower 15.
[0128] Fig. 2A illustrates a schematic view of a pyrolysis plant 2 according to the invention. The pyrolysis plant 2 comprises a reactor 3 configured for producing pyrolysis gas 28 from biomass 30. The reactor 3 comprises a reaction channel 4 having an integrated heating circuit 18 that is configured to heat the reaction channel 4 to a temperature that is high enough to gasify the biomass 30. The pyrolysis plant 2 is configured to receive comminuted biomass 30.
[0129] The pyrolysis plant 2 comprises a feed section 6 designed for feedingcomminuted biomass 30 into the reaction channel 4 via a biomass intake section 34. The biomass intake section 34 will typically have a tubular (e.g. conical) form. The biomass intake section 34 is connected to a vertically arranged section.
[0130] The biomass 30 enters the feed section 6 and passes through a sluice 7. The sluice 7 may be a rotary wheel sluice 7. The sluice 7 is designed to limit the quantity of oxygen that enters the reactor 3 so that the comminuted biomass 30 is fed into the reaction channel 4 in a manner the minimizes the amount of oxygen entering the reactor 3 together with the biomass 30. In an embodiment, the feed section 6 comprises a gravity feeder.
[0131] The reaction channel 4 is configured to generate a flow Q of gasified biomass 30. The flow Q will cause a recirculation of a portion of the gasified biomass 30 in the reaction channel 4. To introduce one-way flow Q, one or more non-return valves 17 may be arranged in the reaction channel 4. This is, however, only optional. The flow direction 11 is indicated.
[0132] In an embodiment, several non-return valves 17 are arranged in the reaction channel 4 to ensure a uniform direction of the flow Q. The disclosure enables that the velocity at which biomass 30 is feed into the reaction channel 4 can be used to regulate the flow Q.
[0133] When the flow Q must be increased, the velocity at which biomass 30 is feed into the reaction channel 4 is increased. When the flow Q must be decreased, the velocity at which biomass 30 is feed into the reaction channel 4 is decreased. If the flow Q is at a desired level, the velocity at which biomass 30 is feed into the reaction channel 4 is maintained.
[0134] The pyrolysis plant 2 comprises one or more flow sensors 9 arrangedand configured to detect the flow Q. The one or more flow sensor 9 will typically be arranged in the reaction channel 4.
[0135] In an embodiment, a single flow sensor 9 is arranged in the reaction channel 4. In an embodiment, two or more flow sensors 9 are arranged in the reaction channel 4.
[0136] The pyrolysis plant 2 comprises a control unit 12 arranged and configured to control the flow Q in the reaction channel 4. The control unit 12 connected to the feed section 6 and control the velocity at which biomass 30 is feed into the reaction channel 4 via the sluice 7. The control unit 12 is arranged and configured to regulate the flow Q by using the flow measurements of the one or more flow sensors 9 and regulating the velocity at which biomass 30 is feed into the reaction channel 4.
[0137] In an embodiment, the feed section 6 comprises a screw feeder (not shown). In this embodiment the control unit 12 can control the speed of the screw feeder and thus control the velocity at which biomass 30 is feed into the reaction channel 4.
[0138] In an embodiment, the feed section 6 comprises an air flow generator (not shown) arranged and configured to generate an air flow capable of distributing biomass 30 to the sluice 7. In this embodiment, the control unit 12 can control the speed of the air flow generator and thus control the velocity at which biomass 30 is feed into the reaction channel 4. The air flow generator may comprise a fan (e.g. an electrically controlled fan).
[0139] The reaction channel 4 is configured to recirculate the pyrolysis gas 28 generated in the reaction channel 4. The pyrolysis plant 2 comprises a combustion air inlet pipe 32 configured to introduce combustion air 52into the reaction channel 4. In an embodiment, the combustion air 52 is a predefined mix of O2 and inactive gas. In an embodiment, the combustion air 52 is a predefined mix of O2 and CO2. In an embodiment, the combustion air 52 is a predefined mix of O2 and steam. In an embodiment, the combustion air 52 is atmospheric air.
[0140] The reaction channel 4 comprises a first conduit 22 that is in connected to a curved portion of the reaction channel 4. The reaction channel 4 comprises a second conduit 22' that is in connected to the first conduit 22. Accordingly, the first conduit 22 and the second conduit 22' are in fluid communication with each other. In an embodiment, the first conduit 22 is directly connected to the second conduit 22'. In an embodiment, the first conduit 22 is directly connected to a cyclone 24 that is connected to the second conduit 22'.
[0141] The cyclone 24 is arranged and configured to remove biochar from the reaction channel 4. The biochar leaves the cyclone 24 via an outlet structure 44. In an embodiment, the cyclone 24 is arranged and configured to remove biochar from the first conduit 22 of the reaction channel 4.
[0142] In an embodiment, the cyclone 24 is arranged at an end portion of the first conduit 22 of the reaction channel 4. Hereby, the majority (if not all of) the biochar 42 will be collected before being transported via the second conduit 22'.
[0143] The cyclone 24 comprises an outlet structure provided with a biochar outlet 21. The outlet structure is provided with a gas inlet 19 for a flowing gas needed to drive the cyclone 24.
[0144] The second conduit 22' is connected to a gas cleaning unit 26 that is configured to clean the pyrolysis gas 28 generated in the reactionchannel 4. The gas cleaning unit 26 comprises a pyrolysis gas outlet 23, by which cleaned pyrolysis gas can be released.
[0145] The gas cleaning unit 26 comprises a waste outlet 25 for waste oil. The gas cleaning unit 26 comprises a heat outlet 27. The heat outlet may comprise a media circulated inside the gas cleaning unit 26 to allow heat exchange between the pyrolysis gas inside the gas cleaning unit 26 and the media being circulated.
[0146] Fig. 2B illustrates a schematic view of a pyrolysis plant 2 according to the invention. The pyrolysis plant 2 basically corresponds to the one shown in and explained with reference to Fig. 2A. The second conduit 22' is, however, connected to the vertically arranged section so that produced pyrolysis gas 28 is being recirculated. The pyrolysis plant 2comprises a blower 15 arranged to generate a and / or increase the flow in the reaction channel 4. In an embodiment, the blower 15 is arranged in the second conduit 22'. In an embodiment, the blower 15 is arranged in the first conduit 22. In an embodiment, the blower 15 is arranged in the curved portion of the reaction channel 4.
[0147] The blower 15 can be used during start-up of the pyrolysis plant 2. During operation of the pyrolysis plant 2 the blower 15 would typically not be needed.
[0148] The control unit 12 is communicatively connected to the blower 15. Accordingly, the control unit 12 can regulate the activity of the blower 15, including turning on the blower 15, turning off the blower 15 and regulating and changing the speed of the bower 15.
[0149] Fig. 3 illustrates a flowchart illustrating main principles of the method according to the invention.
[0150] When the method is pyrolysis plant is started the first step I is to:
[0151] "Feed biomass 30 via the sluice 7 into the reaction channel 4 and detectthe flow Q in the reaction channel 4
[0152] During this step, the comminuted biomass 30 is transported from a biomass storage unit (e.g. a silo or tank) to the sluice 7. The sluice 7 is configured to limit the quantity of oxygen that enters the reactor 3. Accordingly, the comminuted biomass 30 is fed into the reaction channel 4 in a manner the minimizes the amount of oxygen entering the reactor 3 together with the biomass 30. In an embodiment, the sluice 7 is a rotary wheel sluice.
[0153] The next step (II) is to determine if the following question is correct: "Is the flow Q within a predefined flow range?"
[0154] If the flow Q is within the predefined flow range, the first step I is repeated. If the flow Q, on the other hand, is not within the predefined flow range, the third step III carried out.
[0155] The third step III is to determine if the following question is correct: "Is the flow Q lower than the predefined minimum allowable flow Qmin?"
[0156] If the flow Q is lower than the predefined minimum allowable flow Qmin, the fourth step IV is carried out. In the fourth step IV, the flow Q is increased by increasing the velocity at which biomass 30 is feed into the reaction channel 4.
[0157] If, however, the flow Q is higher than the predefined minimum allowable flow Qmin, the fifth step V is carried out. In the fifths step V, the flow Q is reduced by decreasing the velocity at which biomass 30 is feed into the reaction channel 4.
[0158] After the fourth step and after the fifths step, the first step I is repeated.The flow Q will typically be detected by using one or more flow sensors arranged to detect the flow Q in the reaction channel 4. The regulation of the flow Q will typically be carried out by using a control unit that is communicatively connected to the one or more flow sensors and to the unit that controls the velocity at which biomass 30 is feed into the reaction channel 4.
[0159] Fig. 4A illustrates a schematic view of a pyrolysis plant 2 according to the invention. The pyrolysis plant 2 comprises a silo 40 that is used for storing biochar (preferably comminuted biomass). The silo 40 comprises an outlet conduit 36 protruding from a lower side portion of the silo 40. The outlet conduit 36 is connected to a flow generating unit 15' that may be formed as a blower. The flow generating unit 15' is arranged and configured to create an air flow capable of transporting comminuted biomass received via the outlet conduit 36.
[0160] The pyrolysis plant 2 comprises a reactor 3 comprising at least one reaction channel 4. The pyrolysis plant 2 comprises a feed section 6 arranged to feed biomass into the at least one reaction channel that has at least one integrated heating circuit (not shown) configured to heat the at least one reaction channel 4 to a temperature that is high enough to gasify the biomass.
[0161] In an embodiment, the pyrolysis plant 2 comprises a cyclone 24' arranged between the flow generating unit 15' and the feed section 6. In this embodiment, a first connection conduit 36' connects the flow generating unit 15' and the cyclone 24', while a second connection conduit 36" connects the cyclone 24' and the feed section 6. It is, however, possible to omit the cyclone 24'.
[0162] The feed section 6 configured for feeding the biomass 30 into thereaction channel 4. The biomass 30 enters the feed section 6 and passes through a sluice 7. The sluice 7 is configured to limit the quantity of oxygen that enters the reactor 3. Accordingly, the comminuted biomass is fed into the reaction channel 4 in a manner the minimizes the amount of oxygen entering the reactor 3 together with the biomass 30. In an embodiment, the sluice 7 is a rotary wheel sluice. The pyrolysis plant 2 comprises a control unit 12 arranged and configured to control the flow of pyrolysis gas in the reaction channel 4. The control unit 12 is connected to the feed section 6 by using a wired connection 38 and thus configured to control the velocity at which biomass 30 is feed into the reaction channel 4. The control unit 12 is connected to the flow generating unit 15' by a wired connection 38" and to the cyclone 24' (if any) by a wired connection 38'. Any of the wired connections 38, 38', 38" may be replaced by wireless connections (corresponding transceivers and receivers).
[0163] The reaction channel 4 comprises a vertically arranged section. In one embodiment, a heating circuit 18 is integrated in the vertically arranged section. The heating may be provided by burning pyrolysis gas produced by the pyrolysis plant 2.
[0164] The reaction channel 4 comprises a first conduit 22 that is connected to the bottom portion of the vertically arranged section of the reaction channel 4. The reaction channel 4 comprises a second conduit 22' that is in connected to the top portion of the vertically arranged section of the reaction channel 4. The first conduit 22 and the second conduit 22' are in fluid communication with each other. In an embodiment, the first conduit 22 is directly connected to the second conduit 22'. In an embodiment, the first conduit 22 is directly connected to a cyclone 24 that is connected to the second conduit 22'.
[0165] The cyclone 24 is arranged and configured to remove biochar 42 fromthe reaction channel 4. In an embodiment, the cyclone 24 is arranged and configured to remove biochar 42 from the first conduit 22 of the reaction channel 4.
[0166] In an embodiment, the cyclone 24 is arranged at an end portion of the first conduit 22 of the reaction channel 4. Hereby, the majority (if not all of) the biochar 42 will be collected before being transported upwards via the second conduit 22'.
[0167] The pyrolysis plant 2 comprises a blower 15 arranged to generate a and / or increase the flow in the reaction channel 4. In an embodiment, the blower 15 is arranged in the second conduit 22'. In an embodiment, the blower 15 is arranged in the first conduit 22.
[0168] The blower 15 can be used during start-up of the pyrolysis plant 2. During operation of the pyrolysis plant 2, however, the blower 15 would typically not be needed.
[0169] The control unit 12 is communicatively connected to the blower 15 by a wired connection 38'". Accordingly, the control unit 12 can regulate the activity of the blower 15, including turning on the blower 15, turning off the blower 15 and regulating and changing the speed of the bower 15.
[0170] In an embodiment, the cyclone 24 is arranged at an end portion of the first conduit 22 of the reaction channel 4. Hereby, the majority (if not all of) the biochar 42 will be collected before being transported upwards via the second conduit 22'.
[0171] The cyclone 24 comprises an outlet structure 44 provided with a biochar outlet 21. The outlet structure is provided with a gas inlet 19 for a flowing gas needed to drive the cyclone 24.
[0172] The second conduit 22' is connected to a gas cleaning unit 26 that isconfigured to clean the pyrolysis gas 28 generated in the reaction channel 4. The gas cleaning unit 26 comprises a pyrolysis gas outlet 23, by which cleaned pyrolysis gas can be evacuated.
[0173] The gas cleaning unit 26 comprises a waste outlet 25 for waste oil. The gas cleaning unit 26 comprises a heat outlet 27. The heat outlet may comprise a media circulated inside the gas cleaning unit 26 to allow heat exchange between the pyrolysis gas inside the gas cleaning unit 26 and the media being circulated.
[0174] Fig. 4B illustrates a schematic view of a feed section 6 of a pyrolysis plant according to the invention. The feed section 6 comprises a conduit 36 through which comminuted biomass 30 enters the feed section 6. The feed section 6 comprises a basically ring-shaped guide structure 46 configured to recirculate air and transport comminuted biomass 30. Hereby, the guide structure 46 of the feed section 6 can provide a uniform flow distribution of comminuted biomass 30. Thus, a steady flow of comminuted biomass 30 will be filled into the rotary wheel sluice 7. Accordingly, it is possible to achieve a steady velocity at which comminuted biomass 30 is feed into the reaction channel 4 of the pyrolysis plant.
[0175] A blower 15" is arranged in the conduit 36. The blower 15" is arranged and configured to generate an air flow Q' capable of sucking comminuted biomass 30 from the conduit 36 into the guide structure 46. Moreover, the air flow Q' will transport the comminuted biomass 30 via the conduit 36 into the guide structure 4.
[0176] In an embodiment, the pyrolysis plant is configured to ensure that the pressure P2 inside the reaction channel 4 exceed the pressure Pi in the guide structure 46. Hereby, it is possible to further limit the flow of oxygen from the guide structure 46 to the reaction channel 4 via thesluice 7.
[0177] In an embodiment, at least one pressure sensor 48' is arranged to detect the pressure Pi in the guide structure 46 and at least one pressure sensor 48 is arranged to detect the pressure P2 in the reaction channel 4. Hereby, it is possible to monitor the pressure Pi in the guide structure 46 and the pressure P2 in the reaction channel 4.
[0178] In an embodiment, the pyrolysis plant comprises a control unit configured to regulate the pressure P2 in the reaction channel 4. This may be done by regulating the velocity at which biomass 30 is feed into the reaction channel 4.
[0179] In an embodiment, the pyrolysis plant comprises a control unit configured to regulate the pressure Pi in the guide structure 46. This may be done by regulating the speed of the blower 15"
[0180] It is important to underline that the sluice 7 may be replaced with other types of sluices.
[0181] Fig. 5A illustrates schematic view of a pyrolysis plant 2 according to the invention. The pyrolysis plant 2basically correspond to the one shown in and explained with reference to Fig 1A. Fig. 5B illustrates a close-up view of a portion of the pyrolysis plant shown in Fig 5A.
[0182] Heated steam 54 is introduced in an inlet portion of a pipe structures connected to the cyclone 24. Minerals 56 leaves the pipe structure via a mineral outlet, while the heated steam 54 flows through the pipe structure towards the cyclone 24. The heated steam may be heated up to a high temperature in the range 750-850°C such as 800 °C. The pressure may be up to 300 MPa and the retention time may be 15-25 minutes (such as 20 minutes). The heated steam 54 facilitatesgeneration of an increased quantity of H2. Accordingly, gasses 58 such as H2, CO2and CO are collected from the pipe structure via the cyclone 24. H2is extracted from the gasses 58 in a processing unit 60. Accordingly, larger amounts of H2can be generated.List of reference numerals
[0183] 2 Pyrolysis plant
[0184] 3 Reactor
[0185] 4 Reaction channel
[0186] 6 Feed section
[0187] 7 Sluice
[0188] 9, 9' Flow sensor
[0189] 11 Flow direction
[0190] 12 Control unit
[0191] 15, 15', 15" Blower
[0192] 17 Non-return valve
[0193] 18 Heating circuit
[0194] 19 Gas inlet
[0195] 21 Biochar outlet
[0196] 22, 22' Conduit
[0197] 23 Pyrolysis gas outlet
[0198] 24 Cyclone
[0199] 25 Waste outlet
[0200] 26 Gas cleaning unit
[0201] 27 Heat outlet
[0202] 28 Pyrolysis gas
[0203] 30 Biomass
[0204] 32 Combustion air inlet pipe 34 Biomass intake section 36, 36', 36" Conduit
[0205] 38, 38', 38", 38'" Wired connection
[0206] 40 Silo
[0207] 42 Biochar
[0208] 44 Outlet structure
[0209] 46 Guide structure
[0210] 48, 48' Pressure sensor50 Vertically arranged section 52 Combustion air
[0211] Q Flow of pyrolysis gas
[0212] Q' Air flow
[0213] Qmin Minimum allowable flow Pl, p2Pressure
[0214] 54 Steam
[0215] 56 Minerals
[0216] 58 Gasses
[0217] 60 Processing unit
Claims
Claims1. A pyrolysis plant (2) comprising a reactor (3) for producing pyrolysis gas (28) from biomass (30), wherein the reactor (3) comprises at least one reaction channel (4) configured to circulate the pyrolysis gas (28) generated in the reaction channel (4), wherein the reaction channel (4): a) has at least one integrated heating circuit (18) configured to heat the at least one reaction channel (4) to a temperature that is high enough to gasify the biomass (30) andb) is configured to generate a sufficiently large flow (Q) of the produced pyrolysis gas (28) to carry the biochar (42) in the reaction channel (4), wherein the pyrolysis plant (2) comprises a feed section (6) configured for feeding the biomass (30) into the at least one reaction channel (4), wherein the pyrolysis plant (2) comprises one or more flow sensors (9, 9') arranged and configured to detect the flow (Q) in the at least one reaction channel (4),characterised in that the pyrolysis plant (2) comprises:a control unit (12) arranged and configured to control the flow (Q) in the at least one reaction channel (4) by regulating the velocity at which biomass (30) is feed into the at least one reaction channel (4),wherein the pyrolysis plant (2) is configured to be operated without using any blower (15) when the at least one reaction channel (4) has been heated to the temperature that is high enough to gasify the biomass (30).
2. Pyrolysis plant (2) according to claim 1, wherein the pyrolysis plant (2) comprises a blower (15) arranged to increase the flow (Q), wherein the control unit (12) is communicatively connected to and configured to control the blower (15).
3. Pyrolysis plant (2) according to claim 1 or 2, wherein the heating circuit (18) is configured to receive and combust a combustion gas,preferably pyrolysis produced by the pyrolysis plant (2), wherein the heating circuit (18) and the at least one reaction channel (4) are not in fluid communication, wherein at least a portion of the heating circuit (18) is provided and extends inside the at least one reaction channel (4).
4. Pyrolysis plant (2) according to claim 3, wherein the reaction channel (4) comprises a vertically arranged section (50), wherein the integrated heating circuit (18) is arranged in the vertically arranged section (50), wherein the vertically arranged section (50) is at least 5 m.
5. Pyrolysis plant (2) according to claim 4, wherein the reaction channel (4) comprises a first conduit (22) that is in connected to a bottom portion of the vertically arranged section (50), wherein the reaction channel (4) comprises a second conduit (22') that is in connected to a top portion of the vertically arranged section (50), wherein the first conduit (22) and the second conduit (22') are in fluid communication with each other.
6. Pyrolysis plant (2) according to claim 5, wherein the first conduit (22) is directly connected to a cyclone (24) that is connected to the second conduit (22'), wherein the cyclone (24) is arranged and configured to remove biochar (42) from the reaction channel (4) by guiding biochar 42) through an outlet structure (44), wherein the cyclone (24) is arranged and configured to remove biochar (42) from the first conduit (22).
7. Pyrolysis plant (2) according to one of the claims 1-3, comprising a combustion air inlet pipe (32) configured to introduce combustion air (52) into the reaction channel (4), wherein the reaction channel (4) constitutes the heating circuit (18).
8. Pyrolysis plant (2) according to one of the claims, comprising a feed section (6) designed for feeding comminuted biomass (30) into the reaction channel (4), wherein the feed section (6) comprises or is connected to a sluice (7) configured to limit the quantity of oxygen that enters the reactor (3) so that the comminuted biomass (30) is fed into the reaction channel (4) in a manner that reduces the amount of oxygen entering the reactor (3) together with the biomass (30).
9. Pyrolysis plant (2) according to one of the claims, comprising one or more non-return valves (17) arranged in the reaction channel (4).
10. Pyrolysis plant (2) according to one of the claims 8-9, comprising a feed section (6) that comprises a conduit (36) through which comminuted biomass (30) enters the feed section (6), wherein the feed section (6) comprises a ring-shaped guide structure (46) configured to recirculate air and comminuted biomass (30) to provide a uniform flow distribution of comminuted biomass (30), wherein a blower (15") is arranged in the conduit (36), said blower (15") being arranged and configured to generate an air flow (Q') capable of:- sucking comminuted biomass (30) from the conduit (36) into the guide structure (46) and- circulating the comminuted biomass (30) in the conduit (36), wherein the guide structure (46) is arranged and configured to feed the sluice (7).
11. Pyrolysis plant (2) according to claim 10, wherein the pyrolysis plant (2) is configured to ensure that the pressure (P2) inside the reaction channel (4) exceed the pressure (Pi) in the guide structure (46).
12. Pyrolysis plant (2) according to claim 11, wherein at least one pressure sensor (48') is arranged to detect the pressure (Pi) in theguide structure (46) and at least one pressure sensor (48) is arranged to detect the pressure (P2) in the reaction channel (4).
13. A method for producing pyrolysis gas (28) from biomass (30) by using a pyrolysis plant (2) comprising a reactor (3) for producing pyrolysis gas (28) from biomass (30), wherein the reactor (3) comprises at least one reaction channel (4) configured to circulate the pyrolysis gas (28) generated in the reaction channel (4), wherein the reaction channel (4):a) has at least one integrated heating circuit (18) configured to heat the at least one reaction channel (4) to a temperature that is high enough to gasify the biomass (30) andb) is configured to generate a sufficiently large flow (Q) of produced pyrolysis gas (28) to carry the biochar in the reaction channel (4), wherein the pyrolysis plant (2) comprises a feed section (6) configured for feeding the biomass (30) into the at least one reaction channel (4), wherein the method comprising:detecting the flow (Q) in the at least one reaction channel (4) by using one or more flow sensors (9, 9'),characterised in that the method comprising:by using a control unit (12) controlling the flow (Q) in the at least one reaction channel (4) by regulating the velocity at which biomass (30) is feed into the at least one reaction channel (4); operating the pyrolysis plant (2) without using any blower (15) when the at least one reaction channel (4) has been heated to the temperature that is high enough to gasify the biomass (30).
14. Method according to claim 13, comprising:- during starting up the pyrolysis plant (2), by using the control unit (12) being communicatively connected to and configured to control a blower (15) applying said blower (15) to generate a flow (Q) in the at least one reaction channel (4).
15. Method according to claim 13 or 14, comprising:- applying a heating circuit (18) configured to receive and combust a combustion gas, preferably pyrolysis produced by the pyrolysis plant (2) to generate heat, wherein the heating circuit (18) and the at least one reaction channel (4) are not in fluid communication, wherein at least a portion of the heating circuit (18) is provided and extends inside the at least one reaction channel (4).
16. Method according to one of the claims 13-15, comprising:Applying a reaction channel (4) comprising a vertically arranged section (50), wherein the integrated heating circuit (18) is arranged in the vertically arranged section (50), wherein the vertically arranged section (50) is at least 5 m.
17. Method according to one of the claims 13-16, comprising:- feeding comminuted biomass (30) into the reaction channel (4) by using a feed section (6) comprising or being connected to a sluice (7) configured to limit the quantity of oxygen that enters the reactor (3) so that the comminuted biomass (30) is fed into the reaction channel (4) in a manner that reduces the amount of oxygen entering the reactor (3) together with the biomass (30).
18. Method according to one of the claims 13-17, comprising: applying one or more non-return valves (17) arranged in the reaction channel (4) to ensure a uniform direction of the flow (Q).
19. Method according to one of the claims 13-17, comprising: applying a feed section (6) to feed biomass (30) into the sluice (7), wherein the feed section (6) comprises a conduit (36) through which comminuted biomass (30) enters the feed section (6) to feed , wherein the feed section (6) comprises a ring-shaped guide structure (46)configured to recirculate air and comminuted biomass (30) to provide a uniform flow distribution of comminuted biomass (30), wherein a blower (15") is arranged in the conduit (36), said blower (15") being arranged and configured to generate an air flow (Q') capable of:- sucking comminuted biomass (30) from the conduit (36) into the guide structure (46) and- circulating the comminuted biomass (30) in the conduit (36), wherein the guide structure (46) is arranged and configured to feed the sluice (7).
20. Method according to one of the claim 19, comprising the step of ensuring that the pressure (P2) inside the reaction channel (4) exceed the pressure (Pi) in the guide structure (46) by using:at least one pressure sensor (48') arranged to detect the pressure (Pi) in the guide structure (46) andat least one pressure sensor (48) is arranged to detect the pressure (P2) in the reaction channel (4).