Method and apparatus for producing hydrogen from heterogeneous wastes

Abstract

The present invention relates to a system for extracting hydrogen from chemical organic feedstocks, comprising: a thermal gasifier supplied with a chemical-organic feedstock, the thermal gasifier configured to heat the feedstock to a temperature of at least 800°C while conveying the feedstock through the thermal gasifier by an auger and to collect hot gases; a duct line configured to convey the hot gas to a high temperature reformer that subjects the hot gas to a temperature of 1200°C to 1400°C and releases a high temperature reformed gas; a duct line for conveying the hot reformed gas to a heating chamber of the thermal gasifier, the heating chamber including a chamber outlet for discharging the reformed gas after circulating within the heating chamber; a duct line conveying the reformed gas from the chamber outlet to a device configured to separate hydrogen from the reformed gas; and A hydrogen reservoir for the hydrogen produced by the device.

Description

[Technical Field]

[0001] This application claims priority to U.S. Provisional Application No. 63 / 414,403, filed October 7, 2022, and U.S. Patent Application No. US 18 / 114,175, filed February 24, 2023, the contents of which are incorporated herein by reference in their entireties.

[0002] The present invention relates to the field of gasification, and more particularly to the production of syngas and hydrogen by pyrolysis of waste materials, such as municipal solid waste, comprising or not a biomass.

[0003] In this text, unless otherwise specified, hydrogen means dihydrogen (H2).

[0004] Unless otherwise specified, the term "organic", when referring to a substance or product, is to be interpreted as relating to organic chemistry in the broad sense, i.e., as relating to a product or substance comprising compounds containing covalently bonded carbon. [Background technology]

[0005] Hydrogen can be used as an energy vector, for example in fuel cells, to produce electricity and power the motors of electric vehicles or any electrical appliance, without emitting greenhouse gases (GHG) such as CO2.

[0006] However, as of the filing date of this patent application, 96% of hydrogen is produced by reforming (converting) fossil fuel natural gas without carbon capture, which results in approximately nine times the weight of the produced hydrogen being emitted into the atmosphere as GHGs (greenhouse gases).

[0007] So-called green hydrogen can be produced by electrolysis of water, but the yield is very low, about 35%, when comparing the electrical energy used to perform the electrolysis with the power released from the fuel cell, and even less when the energy required to compress the hydrogen, which must be transferred and compressed to, say, 700 bar (10,290 psi), is taken into account.

[0008] Biomass gasifiers are also used to extract hydrogen from various forms of biomass, such as sewage sludge.

[0009] According to this process, pyrolysis of biomass produces pyrolysis gas, which is further reformed to produce synthesis gas, a gas mixture of CO, HO, CO, CH, and H, from which hydrogen can be selectively extracted, for example, by a pressure swing adsorption (PSA) process. DISCLOSURE OF THE INVENTION [Problem to be solved by the invention]

[0010] Gasification can be thought of as a partial combustion process in which steam reacts with carbon contained in a solid carbonaceous fuel or feedstock.

[0011] This reaction occurs at high temperatures, e.g., 800°C to 1,000°C (1,472°F to 1,832°F). It is an endothermic reaction, meaning that the reaction consumes heat and requires a heat source to support it.

[0012] Conventional gasifiers generate such heat, for example, by burning a small amount of the feedstock to sustain the gasification reaction and supplying sufficient air or pure oxygen to reach the desired gasification temperature, a process known as partial oxidation.

[0013] While biomass combustion emits GHGs (greenhouse gases), these GHGs are captured in the short term by the biomass rather than the fossil fuel. However, such combustion actually burns the fuel / feedstock, and as a result, a trade-off must be found between the desired gasification temperature and the amount of feedstock consumed to generate the required heat. That is, partial oxidation "consumes" a portion of the feedstock, thereby reducing the potential for hydrogen production from that feedstock.

[0014] According to another example of the prior art, the raw material is heated via a heat transfer medium such as a solid medium such as sand or ceramic beads.

[0015] Such a method is disclosed in document WO 2021 / 221164, in which a heat carrier medium is heated in a preheating device and then heated in contact with a biomass-based feedstock and pyrolyzed by heat exchange.

[0016] Pyrolysis gas reformers partially combust a small amount of the gas produced by pyrolysis with a supply of oxygen or air. To control combustion and temperature, reformers implementing this method have two valves: one that controls the continuous supply of air or oxygen, and a second that controls the intermittent supply of air or oxygen to the reformer.

[0017] However, although such devices are effective in extracting hydrogen from biomass feedstocks, their efficiency is questionable in terms of energy consumption, particularly due to the energy required to preheat the heat carrier, and the investment required for expensive equipment such as systems for heat carrier supply, collection, char separation, and heating, as well as complex valve systems.

[0018] Another prior art system uses plasma to gasify the feedstock, with temperatures of around 4,000° C. In addition to being investment intensive, such a solution requires high maintenance costs, as the inner walls of the reactor are exposed to very high temperatures. [Means for solving the problem]

[0019] The present invention aims to overcome the drawbacks of the prior art and to achieve this, relates to a system for extracting hydrogen from a chemically organic feedstock, comprising: an organic waste feeder unit; a screw thermo-gasifier having a first end and a second end, wherein an organic feedstock is supplied through a feedstock inlet at the first end, the thermo-gasifier being configured to heat the organic feedstock to a temperature of at least 800°C while conveying the organic feedstock in a gasification chamber with an auger from the first end to a solid residues outlet at the second end, and to collect hot gases in a thermogas collector; a first duct line configured to transport the hot gas from the hot gas collector to a thermogas inlet of a high temperature reformer, the high temperature reformer subjecting the hot gas to a temperature of 1200°C to 1400°C and discharging the hot reformed gas from a reformed gas outlet; a second duct line transporting the reformed gas from the reformed gas outlet to a reformed gas inlet of a heat chamber of the screw thermal gasifier, the heat chamber being located between a housing of the gasification chamber and an outer housing of the screw thermal gasifier, the second duct line comprising a chamber outlet discharging the reformed gas from the reformed gas inlet to a chamber outlet after circulating in the heat chamber; a third duct line conveying the reformed gas from the chamber outlet to a device configured to separate hydrogen from the reformed gas; and Hydrogen storage for the hydrogen produced by the device.

[0020] Therefore, the present system does not use a solid heat carrier or partial oxidation in direct contact with the feedstock, but instead uses the heat of the reformed gas produced by the high-temperature reformer to indirectly heat the organic feedstock in the screw-type thermal gasifier. This eliminates all the equipment required for heating, circulating, and scrubbing the solid heat carrier medium, as in the prior art, and also avoids the waste of hydrogen precursors due to oxidation. The auger that transports the organic feedstock in the thermo-gasifier allows for fine control of the flow rate of the organic feedstock through the thermal gasifier, improving thorough mixing of the organic feedstock and heat exchange with the gasification chamber walls heated by the heating chamber. Therefore, the heat of the reformed gas, which would otherwise need to be cooled before undergoing hydrogen separation, is recovered in the thermal gasifier, and the organic feedstock can be heated to temperatures of 800°C and above, improving the efficiency of conversion of the organic feedstock to a gas mixture with minimal solid residue.

[0021] The present invention is implemented according to the preferred embodiments disclosed below, which are considered individually or in any technically feasible combination. In one embodiment, a screw thermal gasifier includes two parallel augers that spin and transport the organic feedstock in opposite directions from a first end to a second end in a first gasification chamber and a second gasification chamber, with a connection channel between the first and second gasification chambers. This embodiment allows for a more compact design of the screw thermal gasifier, increased heat transfer from the heating chamber to the organic feedstock within the gasification chamber, improved mixing of the organic feedstock, and better control of the flow rate of the organic feedstock throughout the thermal gasifier.

[0022] Advantageously, at least one of the organic waste feeder unit and the raw material inlet is equipped with a rotary airlock, which allows continuous feeding of the apparatus while it is in use.

[0023] In one embodiment, the screw thermal gasifier includes a steam injection inlet for injecting steam into the gasification chamber, where temperatures exceeding 800°C are reached, causing the steam to react with carbon in the organic feedstock, further increasing the hydrogen production yield.

[0024] Advantageously, the device for separating hydrogen from the reformed gas comprises a carbon capture and sequestration unit, so that hydrogen production by the system of the invention is at least carbon neutral and may even be carbon negative.

[0025] In a preferred embodiment, the carbon capture and sequestration unit utilizes the mineralization of carbon dioxide in a brine solution and the production of carbonate (CO3 -2 This embodiment makes the device carbon negative.

[0026] Advantageously, the high temperature reformer is equipped with an oxy-fuel burner for increasing the temperature of the hot gases into the high temperature reformer.

[0027] Advantageously, the oxy-fuel burner is provided with off-gas discharged from a device for separating hydrogen from the reformed gas.

[0028] In a first embodiment, an apparatus configured to separate hydrogen from a reformate comprises producing grade 5.0 pure hydrogen (H2) and an exhaust gas comprising at least 60% carbon monoxide (CO) and at least 15% hydrogen by volume.

[0029] In a preferred embodiment, in a hydrogen separation unit, the reformed gas is sent to a CO conversion catalyzed Water Gas Shift Reactor (WGSR) to produce WGSR processed gas, which is carbon monoxide-free and further increases the hydrogen fraction at the outlet of the WGSR.

[0030] In a first alternative embodiment, the WGSR process gas is sent to a Vacuum Pressure Swing Absorption CO2 separator before entering the Pressure Swing Absorption device, and the exhaust gas fed to the oxy-fuel burner is hydrogen. This embodiment provides a zero-emission, yet self-sustaining, high-temperature reformer.

[0031] In a second variant, the WGSR process gas is sent to a membrane reactor for hydrogen separation, and the WGSR process gas is heated by heat exchange with reformed gas exiting the high temperature reformer before entering the membrane reactor.

[0032] In one embodiment, the first duct line includes an expansion reactor between the hot gas collector and the hot gas inlet.

[0033] The expansion reactor includes a reactor steam inlet adapted to inject steam into the hot gases within the expansion reactor.

[0034] Advantageously, the expansion reactor comprises a mixing chamber configured to promote mixing of the hot gas and steam by turbulent flow through the mixing chamber, thereby increasing the hydrogen content.

[0035] The reformed gas is cooled in a gas conditioning unit before entering a device adapted to separate hydrogen from the reformed gas, such cooling being performed with water through a heat exchanger.

[0036] The water flowing through the heat exchanger exchanges heat with the reformed gas to generate steam.

[0037] Advantageously, steam is injected not only into the gasification chamber, but also into the expansion reactor and, if present, into the WGSR.

[0038] Advantageously, the system further comprises a boiler equipped with a burner for further increasing the temperature of the water flowing through the heat exchanger, the burner being supplied with reformed gas.

[0039] The present invention also relates to a method for extracting hydrogen from a chemical organic feedstock by implementing the system of the present invention, comprising the steps of: heating the chemical organic feedstock in a thermal gasifier to a temperature of at least 800°C; collecting hot gas from the thermal gasifier and reforming the hot gas into reformed gas in a high temperature reformer at a temperature of 1200°C to 1400°C; and collecting the reformed gas at the outlet of the high-temperature reformer and directing the reformed gas into a heating chamber of a thermal gasifier to indirectly heat the chemical organic feedstock;

[0040] Advantageously, the gas pressure during the steps of heating the organic feedstock, reforming the hot gas and indirectly heating the organic feedstock is from -30 mmwc to 0 relative to atmospheric pressure.

[0041] In one embodiment, the method further includes converting carbon monoxide from the reformed gas in a water-gas shift reactor (WGSR) and compressing the reformed gas to a pressure comprised between 10 bar and 20 bar before entering the water-gas shift reactor (WGSR).

[0042] Advantageously, the method further comprises the steps of separating hydrogen from the reformed gas and, prior to the step of separating hydrogen, increasing the pressure of the reformed gas to a pressure comprised between 20 bar and 30 bar.

[0043] In a preferred embodiment, the gas pressure is gradually increased from the step of collecting the hot gas to the step of separating the hydrogen without going through an expansion step. [Brief explanation of the drawings]

[0044] The present invention will now be described in accordance with preferred, non-limiting embodiments with reference to FIGS. 1 to 6:

[0045] [Figure 1] FIG. 1 illustrates a system according to the present invention.

[0046] [Figure 2] [Figure 2] illustrates a gas conditioning unit between the thermolyzing-reforming unit and the hydrogen separation unit.

[0047] [Figure 3A] FIG. 3A is a simplified longitudinal cross-section of an exemplary embodiment of a screw thermal gasifier.

[0048] [Figure 3B] [Fig. 3B] is a simplified vertical cross-sectional view showing an embodiment of an expansion reactor.

[0049] [Figure 4] FIG. 4 is a simplified vertical cross-sectional view of an exemplary embodiment of a high-temperature reformer.

[0050] [Figure 5] FIG. 5 is a diagram showing the configuration of a hydrogen separation unit.

[0051] [Figure 6] [Figure 6] shows a modification of the device of [Figure 5], in which hydrogen separation is carried out by a membrane reactor. DETAILED DESCRIPTION OF THE INVENTION

[0052] [FIG. 1] In an exemplary embodiment, the system of the present invention includes an organic waste feed unit (100) including a hopper (102) and a hopper loader (101) for feeding chemical organic raw materials into the system.

[0053] Chemical organic feedstocks consist of waste or refuse materials made from organic compounds containing fixed carbon. The system is highly flexible and can accept feedstocks with an ash content of preferably less than 5%, but can also accept feedstocks with an ash content up to 30%. The moisture content of the feedstock can range from 5% to 30%, but is preferably around 15%.

[0054] By way of non-limiting example, chemically organic feedstocks may include plant-derived biomass such as wood chips, tree sawdust, construction waste wood, pruning branches, forest residues, unused trees, agricultural residues such as discarded vegetables and fruits, rice straw, wheat straw, rice husks, seaweed, algae, and fishing residues; biological biomass such as organic municipal solid waste, e.g., livestock waste, sewage sludge, manure, cardboard, plastics, and trash, including food waste; and any combination thereof.

[0055] In order for the system to operate under acceptable conditions, raw material preparation is carried out on-site and / or at a remote waste collection plant.

[0056] Basically, and more specifically, if the raw material comprises municipal waste, it is separated to separate non-organic materials such as metals, glass, cement, etc., and the raw material is crushed after separation. The moisture content can be adjusted by mixing raw materials of different origins, for example, raw materials with low moisture content and raw materials with high moisture content.

[0057] This provision allows the ash and moisture content of the feedstock to be maintained within the appropriate range for the operation of the system.

[0058] Chemical organic feedstock is fed to the gasification and reforming installation (160) and first enters the screw-type thermal gasifier (110) through a feedstock inlet equipped with a first rotary air lock (103). The first rotary air lock (103) prevents hot gases from escaping the thermal gasifier's gasification chamber (118) during feed, thereby allowing for intermittent (discontinuous) and / or continuous feed to the gasification and reforming installation during use.

[0059] In an exemplary illustrative embodiment, the screw thermal gasifier includes an auger (115) rotated within a gasification chamber (118) by a drive (116) located outside the gasification chamber. The auger conveys organic feedstock from a first end (111) to a second end (112) of the thermal gasifier at a controlled rate determined by the pitch and rotational speed of the auger.

[0060] The screw thermal gasifier further comprises a heating chamber (119) separated from the gasification chamber (118) by a wall designed as an inner wall. The heating chamber heats the inner wall of the gasification chamber (118), causing the temperature of the organic feedstock to increase as it moves from the first end (111) to the second end (112) of the thermal gasifier and comes into contact with the inner wall of the gasification chamber (118).

[0061] The temperature of the chemical-organic feedstock rises from room temperature at the outlet of the feeder unit (100) to 800°C (1,472°F) and in the gasification chamber (118) to 900°C (1,652°F), preferably about 850°C (1,562°F).

[0062] In practice, thermal gasifiers provide a large surface area for heat exchange with the interior walls, and by conveying the feedstock with an auger, the feedstock is in contact with this entire surface area and is constantly mixed, thereby allowing for rapid and uniform heating of the feedstock.

[0063] In one embodiment, the screw thermal gasifier (110) is equipped with a steam inlet (313) adapted to inject steam from a steam line (113) into the gasification chamber (118), while the steam is preferably injected into an expansion reactor (120) at the outlet of the screw thermal gasifier.

[0064] The steam / water is obtained from the moisture contained in the organic feedstock and the steam injected into the gasification chamber (118) from the steam line (113) through the steam inlet (313). Therefore, the amount of steam injected into the gasification chamber depends on the nature of the organic feedstock and its moisture content.

[0065] The hot gas resulting from the gasification process, which contains primarily CO, H2O, CO2, CH4 and H2, along with smaller amounts of various other gases, leaves the screw thermal gasifier (110) through a hot gas collector (117) and is conveyed by duct lines (121, 125) to the high temperature reformer (130).

[0066] In a preferred embodiment, the first duct line (121) conducting the hot gas from the chamber outlet of the screw thermal gasifier (110) to the high temperature reformer (130) is equipped with a gas expansion reactor (120), where the hot gas is further mixed with steam from the steam line (113), and the steam-enriched hot gas is transported to the high temperature reformer (130) by the second duct line (125).

[0067] The gas expansion reactor, due to its inherent volume, provides an additional means for maintaining a stable negative pressure in the gas path from the thermal gasifier to downstream gas separation.

[0068] The screw thermal gasifier (110) is provided with a solid residue outlet (114) at its second end (112) for recovering the solid residue of the pyrolyzed feedstock as ash or char. The operating conditions of the thermal gasifier can be adjusted to produce less or more char.

[0069] In a preferred embodiment, the temperature in the gasification chamber is sufficiently high to avoid char formation, i.e., 850°C or higher, so that only ash is collected at the solid residue outlet (114). In another embodiment, if char formation is the goal, the char is conveyed by a char conveyor (122) to the char inlet of the high-temperature reformer (130). The ash (105) is collected and disposed of off-site. The char and ash may also be used as fertilizer, thereby facilitating carbon capture from biomass.

[0070] In a high temperature reformer, the hot gases are exposed to temperatures of at least 1,200°C (2,192°F), preferably up to 1,400°C (2,552°F).

[0071] These high temperatures are achieved by heat provided by an oxy-fuel burner 135. The burner is fed with oxygen from an oxygen line 133 and exhaust gas 193 from a hydrogen separation unit 190. The oxygen line 133 is fed through an oxygen producing device 182, which produces oxygen from air, for example by cryogenic separation.

[0072] In a first example, the exhaust gas contains 60% CO and at least 15% H2.

[0073] In the preferred embodiment, referring to FIG. 5, the so-called exhaust gas is actually H2 collected at the outlet of the hydrogen separation unit.

[0074] Whatever the embodiment, there is no contact with air during combustion of the exhaust gas (193) in the oxy-fuel burner (135), thereby reducing or eliminating NOx emissions, and, in the preferred embodiment, when the exhaust gas is hydrogen, the combustion is clean, producing primarily water vapor, which further facilitates downstream hydrogen recovery and avoids the buildup of unwanted carbon compounds in the reformate gas.

[0075] The high temperature reformer (130) produces a hot gas rich in free H2 called the reformate gas.

[0076] The hot reformate gas (150) exits the hot reformer (130) through the reformate gas outlet (134) and is recycled through the reformate gas inlet via the heating duct line (124) to the heating chamber (119) of the screw thermal gasifier. The heat of the reformate gas is therefore advantageously utilized to raise the temperature of the feedstock. In a preferred embodiment, the majority of the ash is removed from the hot gas at the screw thermal gasifier stage by a particle filter at the thermal gasifier outlet. However, in certain embodiments, the reformate gas may pass through an additional particle separator (140) before being sent to the heating chambers (109)(119) of the screw thermal gasifier.

[0077] According to this particular embodiment, the ash (141) separated from the reformed gas is collected and disposed of.

[0078] In the gasification reformer, the following reactions occur: -Partial oxidation of carbon from organic materials with oxygen: C + O2 → CO2 -Gasification of steam: C + H2O → CO + H2 -Methanation: C + 2H2 → CH4 - Boudoir reaction: C + CO2 → 2CO -Water-gas shift reaction: CO + H2O → CO2 + H2 -Methane reforming reaction: CH4 + H2O → CO + 3H2 - Acid formation: H2 + Cl2 → 2HCl and H2 + S → H2S

[0079] The reformed gas leaves the heating chamber of the thermal screw gasifier through a chamber outlet and is sent to a reformed gas conditioning unit (170) before entering the hydrogen separation unit.

[0080] Therefore, before entering the hydrogen separation unit, the reformed gas is preferably cooled and further treated for contaminants as shown in FIG. 2 to obtain a conditioned reformed gas.

[0081] In an exemplary embodiment, separation of hydrogen from the conditioned reformate gas occurs through a hydrogen separation unit (191) comprising a pressure swing adsorption (PSA) device associated with the carbon capture and sequestration unit (180).

[0082] Those skilled in the art will appreciate that the use of a PSA unit to separate hydrogen from the reformed gas is merely an exemplary embodiment, and that other separation methods, such as membrane separation or cryogenic separation, may be considered without changing the principles of the present invention.

[0083] The reformed gas is cleaned and cooled before entering the hydrogen separation unit. Thus, the reformed gas is at least partially cooled by passing through the heating chamber (119) of the screw thermal gasifier (110), where it exchanges heat with the organic feedstock, but does not come into direct contact with the organic feedstock by flowing inside the jacketed walls of the thermal gasifier.

[0084] The hydrogen produced by the hydrogen separation unit is stored in storage 192, for example in pressurized tanks with a pressure of 300 to 700 bar, to reduce the storage volume, or, according to a variant, it may be liquefied or stored in dry adsorption media such as metal hydrides.

[0085] The carbon capture and sequestration unit (180) processes the carbon dioxide and stores the carbon as carbonates (181).

[0086] By way of example, a carbon capture and sequestration unit (180) of the type sold by CAPTICO2, Solheimsgaten 16, 5058 Bergen, Norway, in which carbon dioxide is mineralized in a brine solution (183) Ca(OH)2. After drying, it can be disposed of, for example, by burial, or sold for specific uses.

[0087] [Figure 2] The partially cooled reformed gas (151) is conveyed by a third duct line to the gas conditioning unit (170) and is first sent to a quenching unit (271) to which water (213) is supplied to reduce its temperature.

[0088] In one embodiment, the reformulated gas passes through a scrubber (273) and a fine particulate filter (272).

[0089] Scrubbing can remove hydrogen chloride, hydrogen sulfide and other corrosive elements from the gas.

[0090] The filter (272) removes very fine ash from the reformulated gas, allowing it to be collected and disposed of.

[0091] Preferably, the reformed gas is further cooled before entering the scrubber. To this end, the reformed gas is cooled before entering the scrubber by passing through a heat exchanger 275 to which a stream of water 213 is supplied. In the heat exchanger, the water is converted to steam, which is then supplied through a steam line 113 to a steam consuming device in the system, such as a reformer, expansion reactor, or thermal screw gasifier.

[0092] During start-up of the system, the flow rate of the reformed gas may not be high enough to generate enough steam through the heat exchanger 275. For this reason, the system further includes a boiler 211 equipped with a boiler burner 209.

[0093] The boiler burner (209) is supplied with reformed gas or LPG via an LPG line (210), although the latter configuration is only used for starting up the equipment.

[0094] From the thermal gasifier and gas reforming stages (160) to the inlet to the reformate gas conditioning unit (170), the unit operates under a slight negative pressure of -30 to 0, preferably -30 to -10 mmwc (millimeters of water column) relative to atmospheric pressure. At the outlet of the filter (272), the pressure of the conditioned reformate gas is increased by a compressor (276) to a pressure of 10 to 20 bar, preferably about 15 bar, before entering the hydrogen separation unit.

[0095] The reformate conditioning unit (170) discharges a conditioned reformed gas (251) which is sent to a hydrogen separation unit.

[0096] In an exemplary embodiment (not shown), the system consists of multiple 20-foot ISO containers that can be stacked and connected together, ready for assembly.

[0097] All components are placed and secured within each container, said container being rigid enough to support all components and its own weight.

[0098] Thus, the installation of the system consists primarily of connecting the piping to the container, which forms the structural frame of the equipment and can be placed on-site on a concrete slab or on steel rafters.

[0099] For this purpose, the components are designed to be as compact as possible.

[0100] [FIG. 3A] In one embodiment, the thermal gasification unit is located in a container above the container containing the reforming unit.

[0101] According to such an embodiment, the screw thermal gasifier (110) is essentially tubular, horizontally oriented, and has a first end and a second end, and means for conveying feedstock introduced into the first end to the second end.

[0102] In an exemplary embodiment, the screw thermal gasifier (110) comprises two parallel augers (3151, 3152) as means for conveying the feedstock, each auger being provided between two bearings (351) (3511, 3512) and driven by two electric drives (3161, 3162). Compared to a rotary kiln, the screw thermal gasifier (110) offers the advantage that the bearings and corresponding sealings are outside the high temperature zone and can be cooled without affecting the operation of the device, thus reducing costs and avoiding the use of lip seals that may leak reformed gas into the atmosphere.

[0103] The two augers (3151, 3152) convey the feedstock in opposite directions over a total travel distance of approximately twice the overall length of the thermal gasifier (110), thereby making the thermal gasifier more compact.

[0104] Each auger (3151, 3152) may be a single or multiple start thread with a constant or variable pitch over its length, the two augers may have different pitches and different pitch variations, and one or both augers may be conical.

[0105] Each auger rotates within a gasification chamber (3181, 3182), and the two gasification chambers are connected to each other via connecting channels (311) (322), so that the raw material is fed into the screw-type thermal gasifier (110) by a feeding hopper (303) at a first end (feeding end) of the first gasification chamber, then carried by the first auger towards the opposite end of the first gasification chamber, and falls into the second gasification chamber (3182) through the connecting channel (311) at its first end, where it is then carried by the second auger (3152) towards the opposite end (collecting end) of the second gasification chamber.

[0106] In an advantageous embodiment, the feed hopper of the raw material inlet of the thermal gasifier is equipped with a second rotary airlock (304).

[0107] This rotary airlock (304) can be used alone or in conjunction with the first rotary airlock (103) upstream of the feed hopper to continuously feed the facility while preventing hot gas from escaping through the feeding port. For this purpose, the feed hopper (303) is advantageously equipped with one or more sensors (3030), such as load cells or load level sensors, to control the feed rate of the material during operation.

[0108] In this exemplary embodiment, the gasification chambers are cylindrical with a circular cross section, however, the cross section of the gasification chambers may be, for example, elliptical, and one or both gasification chambers may be conically elongated to coordinate with the auger shape, cross section, thread, pitch, and pitch change. In an exemplary implementation, the walls of the gasification chambers are heated by a set of tubular ducts (3191, 3192) located around each gasification chamber and carrying the hot reformulated gas.

[0109] The walls of the tubular ducts as well as the gasification chamber are made from ceramics such as aluminum nitride, or from high temperature resistant nickel-based alloys coated with high thermal conductivity ceramics such as aluminum nitride, beryllium oxide, silicon carbide, silicon nitride, etc. to prevent wear and withstand high temperatures.

[0110] The screw thermal gasifier comprises an external enclosure (350), a gasification chamber, and a thermal insulation layer (351) between the enclosure and the gasification chamber.

[0111] In another embodiment, the heating chamber comprises a jacketed space between the inner wall of the gasification chamber and the wall of the outer housing, and the hot reformed gas circulates directly in this jacketed space without being conveyed by a tubular duct.

[0112] The screw thermal gasifier and the entire pyrolysis reforming unit operate under atmospheric pressure or slight negative pressure, so no extra-large thickness is required to withstand high pressure.

[0113] The steam inlet (313) allows for the injection of steam from the steam line (113) into the first gasification chamber (3181) if necessary depending on the moisture content of the feedstock.

[0114] As the feedstock, driven by the auger, moves from the feed end to the disposal end, the organic feedstock, mixed with steam, if applicable, is gasified by the chemical reactions described above and transformed into, on the one hand, solid residues, i.e., char and ash, which are collected at the collection end through one or more solid residue outlets (314), and, on the other hand, into a gas called thermogas, which is essentially synthesis gas, and is collected by a thermogas outlet (321).

[0115] The operating conditions of the system avoid the formation of char. However, if such optimal conditions cannot be reached, for example due to the nature of the feedstock or during system start-up, a small amount of char may be formed, which is collected in the solid residue outlet (314) and, in a preferred embodiment, further transported to the high-temperature reformer by a char conveyor. The ash is disposed of off-site, while the char itself is also disposed of off-site.

[0116] Hot gases are collected in both gasification chambers through piping and sent to an expansion reactor (120) where they are mixed with steam before being sent to a high temperature reformer.

[0117] The screw thermal gasifier is installed horizontally, with the hot gases collected at the top of the screw thermal gasifier, while the solid residue is collected at the bottom of the thermal gasifier, and the feedstock moving along the horizontal axis.

[0118] [FIG. 3B] The expansion reactor (120) is preferably located and mounted next to the screw thermal gasifier, thus realizing a compact installation.

[0119] The expansion reactor comprises an external shell (360) with thermal insulation (361), and the interior walls are made of ceramic or coated with ceramic.

[0120] The hot gases leaving the screw thermal gasifier preferably pass through a particulate filter (325) at the hot gas inlet (320) before entering the expansion reactor (120).

[0121] The expansion reactor allows the pressure in the entire system up to the CO2 separation stage to be kept close to atmospheric pressure, preferably slightly negative, typically -10 to -30 mmwc, and allows steam to be injected into the hot gases released from the thermal gasifier. Steam is injected from the steam line (113) by the Venturi effect.

[0122] The expansion reactor includes a mixing chamber (301) where steam injection promotes turbulence in the hot gas stream, promoting mixing of the steam and hot gas and promoting reaction. The steam also provides a source of additional hydrogen for the hot gas, while the expansion reactor provides residence time and space for the gas reaction to occur.

[0123] Hot gas leaves the expansion reactor through hot gas outlet (321) and is sent to a high temperature reformer.

[0124] When the system is installed in stacked containers, the container with the high temperature reformer is installed below (at the bottom) the container with the screw thermal gasifier and expansion reactor.

[0125] [Figure 4] In an exemplary embodiment, the high-temperature reformer (130) is horizontally mounted and includes an outer shell (460), a thermal barrier (461), and a ceramic internal lining. Steam-enriched thermogas exiting the expansion reactor enters one end of the high-temperature reformer through a hot gas inlet (421), and if char is present, is conveyed to a char inlet (414) by a char conveyor (122). The steam-enriched thermogas entering the high-temperature reformer through a second duct line (125) is enriched with steam via steam injection within the expansion reactor.

[0126] The oxy-fuel burner (135) is fed with exhaust gas (193) containing H2 and CO produced as a by-product of the hydrogen separation unit, or in the preferred embodiment, as part of the H2 produced in the hydrogen separation unit, which is suitably captured and piped. The oxy-fuel burner is fed with industrial grade oxygen, so that combustion does not involve air and there is no possibility of NOx production.

[0127] Combustion creates a hot flame (435) within the reformer, the temperature within which can rise to 1400°C.

[0128] The reformate gas (150) exits the hot reformer through the reformate gas outlet (434) and the solid residue is collected at the bottom of the reformer through an ash hatch (440) equipped with a rotary valve airlock (403). The ash is then disposed of off-site.

[0129] As mentioned above, the hot reformed gas (150) is sent to a particle cleaning station before being conditioned and sent to a hydrogen separation unit, with a portion of it first passing through the heating chamber of a screw thermal gasifier before passing through the reformed gas conditioning unit.

[0130] [FIG. 5] In a preferred embodiment, the conditioned reformate gas (251) discharged from the reformate gas conditioning unit (170), which is rich in H but also contains CO, CO, and N, first enters a CO conversion water gas shift reactor (591, WGSR).

[0131] The WGSR contains a catalytic media and uses steam injected from steam line (113) to react carbon monoxide in the reformed gas to produce hydrogen and carbon dioxide. The WGSR (591) removes 100% of the carbon monoxide and significantly increases the hydrogen content of the reformed gas. The WGSR is typically operated at a positive pressure of about 15 bar.

[0132] As the WGSR treated gas (595) containing CO2, H2, and N2 exits the WGSR (591), it is filtered through a filtering and compression unit (592) containing an ultra-fine filter and a screw compressor adapted to compress the reformed gas to a pressure of 20-30 bar before entering a Pressure Swing Absorption CO2 separator (593).

[0133] The PSA separates 100% of the carbon dioxide, leaving only hydrogen and nitrogen in the PSA processed gas (551) which enters the pressure swing adsorption (PSA) unit (590) where the H2 is separated.

[0134] The CO2 (194) is sent to a carbon capture and sequestration unit (180) where the carbon is processed and stored as a solid medium, and other gases, primarily hydrogen, are fed to an oxy-fuel burner.

[0135] The PSA unit (590) produces hydrogen of purity meeting ISO 14687 Grade D specifications for use in PEM fuel cells.

[0136] The hydrogen is stored in a reservoir (192), for example in a pressure tank, and some of it is collected and sent as "exhaust gas" (193) (actually H2) to feed the oxy-fuel burner.

[0137] Therefore, considering the entire system, in this preferred embodiment the gaseous exhaust consists only of steam and nitrogen.

[0138] [FIG. 6] In another embodiment, hydrogen separation is carried out through a membrane reactor (690), such as a palladium membrane reactor.

[0139] According to this embodiment, the WGSR process gas (595) is first sent through a heat exchanger (691) where it is heated to a temperature sufficient to react in the membrane reactor (690).

[0140] In an exemplary embodiment, heating is achieved via heat exchange with reformed gas (151) coming from the high temperature reformer, which is further sent to the heating duct line (124) to heat the heating chamber of the screw thermal gasifier.

[0141] The membrane reactor (690) separates the WGSR treated gas (595) into a CO2-rich stream (694) that is sent to a carbon capture and sequestration unit and fuel cell grade H2 (692) that is sent to storage (192), a portion of which (193) is used to feed the oxy-fuel burner.

[0142] The embodiment described below is less investment intensive than the embodiment shown in Figure 5 and also allows for a 50% increase in H2 production.

[0143] As noted above, in both embodiments, the gas pressure within the system is gradually increased from atmospheric pressure to hydrogen separation and ultimately storage, so that the gas does not undergo an energy-consuming compression-expansion cycle. [Example]

[0144] Example 1

[0145] The following table shows a non-limiting example of the flow of material through an apparatus according to a first embodiment, where an oxy-fuel burner is supplied with exhaust gases containing primarily CO and H2.

[0146] Although the system is capable of converting a mixture of chemical and organic feedstocks such as municipal solid waste, the feedstock considered in this example is wood chips.

[0147] Once steady state is reached, the system will produce approximately 39 kg of hydrogen per hour, resulting in a potential energy output of 1.3 MWh per hour, making it self-sustaining.

[0148] A portion of the hydrogen produced may be used in a fuel cell to generate the power required for the system, for example to drive a thermal screw gasifier. [Table 1]

[0149] <Example 2>

[0150] In this second embodiment, H2 exhaust from the pressure swing adsorption unit is fed to an oxy-fuel burner.

[0151] The raw material is wood chips, and the main components of the process are shown in Table 2. [Table 2]

[0152] Steam is injected into the steam line (113) at a pressure of 10 barg and a temperature of 175°C to supply steam-using units such as the expansion reactor (120), high temperature reformer (130), and WGSR (591).

[0153] Table 3 shows the overall main flow between each station in the equipment. [Table 3]

[0154] Overall, in such a configuration the system produces 69 Kg / h of ISO 14687 Grade D hydrogen and 102 Kg / h of hydrogen mixed with traces of CO2 and N2, which can be used for combustion or sent to a second PSA unit to extract further fuel cell grade H2.

[0155] According to the above example, 22.48 Kg / h of PSA quality H2 is supplied to the oxy-fuel burner.

[0156] The composition of the hot gas is shown in Table 4. [Table 4]

[0157] The composition of the reformed gas at the outlet of the high-temperature reformer is shown in Table 5. [Table 5]

[0158] The composition of the WGSR process gas is shown in Table 6. It should be noted that the gas entering the WGSR unit is before passing through the gas conditioning unit (170). [Table 6]

[0159] The composition of the CO2VPSA treated gas is shown in Table 7. [Table 7]

Claims

1. 1. A system for extracting hydrogen from chemical organic feedstock, comprising: an organic waste supply unit; a screw-type thermal gasifier having a first end and a second end, wherein a chemical-organic feedstock is supplied through a feedstock inlet at the first end, the thermal gasifier being configured to heat the chemical-organic feedstock to a temperature of at least 800°C while conveying the organic feedstock within a gasification chamber from the first end to a solid residue outlet at the second end with an auger, and to collect hot gas in a hot gas collection device; a first duct line configured to transport the hot gas from the hot gas collector to a hot gas inlet of a high temperature reformer, the high temperature reformer subjecting the hot gas to a temperature of 1200°C to 1400°C and discharging the high temperature reformed gas from a reformed gas outlet; a second duct line transporting the reformed gas from the reformed gas outlet to a reformed gas inlet of a heating chamber of a screw thermal gasifier, the heating chamber being located between a housing of the gasification chamber and an outer housing of the screw thermal gasifier, the second duct line comprising a chamber outlet discharging the reformed gas from the reformed gas inlet to the chamber outlet after circulating in the heating chamber; a third duct line conveying the reformed gas from the chamber outlet to an apparatus configured to separate hydrogen from the reformed gas; and A hydrogen reservoir for the hydrogen produced by the device.

2. 2. The system of claim 1, wherein the screw-type thermal gasifier comprises two parallel augers that rotate and transport the organic feedstock in opposite directions from the first end to the second end in the first gasification chamber and the second gasification chamber, respectively, and the screw-type thermal gasifier further comprises a connecting channel between the first gasification chamber and the second gasification chamber.

3. 10. The system of claim 1, wherein at least one of the organic waste feed unit and the raw material inlet comprises a rotary airlock.

4. 10. The system of claim 1, wherein the screw thermal gasifier comprises a steam inlet for injecting steam into the gasification chamber.

5. 10. The system of claim 1, wherein the device for separating hydrogen from the reformed gas comprises a carbon capture and sequestration unit.

6. The carbon capture and sequestration unit is designed to capture and sequestrate carbon dioxide from the brine solution by mineralization and carbonate (CO ３ －２ 6. The system of claim 5, further comprising:

7. 7. The system of claim 6, wherein the high temperature reformer comprises an oxy-fuel burner configured to increase the temperature within the high temperature reformer.

8. 8. The system of claim 7, wherein the oxy-fuel burner is supplied with exhaust gas discharged from a device configured to separate hydrogen from the reformed gas.

9. 10. The system of claim 8, wherein the device configured to separate hydrogen from the reformate produces grade 5.0 pure hydrogen (H2) and an exhaust gas comprising at least 60% carbon monoxide (CO) and at least 15% hydrogen by volume.

10. 10. The system of claim 8, wherein the reformed gas is sent to a CO conversion water-gas shift reactor (WGSR) in an apparatus configured to separate hydrogen from the reformed gas to produce a WGSR process gas.

11. 11. The system of claim 10, wherein the WGSR process gas is sent to a (vacuum) pressure swing adsorption CO2 separator before entering the pressure swing adsorption unit, and the exhaust gas supplied to the oxy-fuel burner is hydrogen.

12. 11. The system of claim 10, wherein the WGSR process gas is sent to a membrane reactor for hydrogen separation, and the WGSR process gas is heated by heat exchange with reformed gas discharged from a high-temperature reformer before entering the membrane reactor.

13. 10. The system of claim 1, wherein the first duct line comprises an expansion reactor between the hot gas collector and the hot gas inlet.

14. 14. The system of claim 13, wherein the expansion reactor comprises a reactor steam inlet configured to inject steam into the hot gas within the expansion reactor.

15. 14. The system of claim 13, wherein the expansion reactor comprises a mixing chamber configured to promote mixing of the hot gas and steam by turbulent flow through the mixing chamber.

16. 15. The system of claim 14, wherein the reformed gas is cooled in the gas conditioning unit before entering the device configured to separate hydrogen from the reformed gas, such cooling being achieved through a heat exchanger that exchanges heat with water.

17. 16. The system of claim 15, wherein water flowing through the heat exchanger exchanges heat with the reformed gas to produce steam.

18. 17. The system of claim 16, further comprising a boiler having a burner for further increasing the temperature of the water flowing through the heat exchanger, the burner being supplied with reformed gas.

19. 17. The system of claim 16, wherein steam is injected into the gasification chamber and into the expansion reactor.

20. 20. The system of claim 18, wherein the apparatus is configured to separate hydrogen from the reformed gas, the reformed gas is sent to a CO conversion water-gas shift reactor (WGSR) to produce a WGSR process gas, and steam is injected into the WGSR.

21. 10. A method for extracting hydrogen from a chemical organic feedstock using the system of claim 1, comprising the steps of: heating the chemical-organic feedstock in a thermal gasifier to a temperature of at least 800°C; collecting hot gas from the thermal gasifier and reforming the hot gas into reformed gas in a high temperature reformer at a temperature of 1200°C to 1400°C; and collecting the reformed gas at the outlet of the high-temperature reformer and directing the reformed gas into a heating chamber of a thermal gasifier to indirectly heat the chemical organic feedstock;

22. 22. The method of claim 21, wherein the gas pressure during the steps of heating the organic feedstock, reforming the hot gas, and indirectly heating the organic feedstock is from -30 mmwc to 0 relative to atmospheric pressure.

23. 23. The method of claim 22, further comprising converting carbon monoxide of the reformed gas in a water gas shift reactor (WGSR); and compressing the reformed gas to a pressure comprised between 10 bar and 20 bar before entering the water gas shift reactor (WGSR).

24. 24. The method of claim 23, further comprising the steps of separating hydrogen from the reformed gas and increasing the pressure of the reformed gas to a pressure comprised between 20 bar and 30 bar prior to the step of separating hydrogen.

25. 25. The method of claim 24, wherein the gas pressure is gradually increased from the step of collecting the hot gas to the step of separating the hydrogen without going through an expansion step.

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