Method and device for preparing hydrogen from heterogeneous waste

Abstract

The present invention provides a system for extracting hydrogen from a chemical organic raw material, comprising: a heat gasifier supplied with the chemical organic raw material and configured to heat it to a temperature of at least 800 DEG C while conveying the chemical organic raw material through a spiral in a gasification chamber and collecting pyrolysis gas; the pipeline is used for conveying the pyrolysis gas to a high-temperature reformer, and the high-temperature reformer enables the pyrolysis gas to be exposed to the temperature ranging from 1200 DEG C to 1400 DEG C and releases high-temperature reformed gas; the pipeline is used for conveying the reformed gas to a heating chamber of the hot gasifier, and the heating chamber is provided with a chamber outlet and is used for circulating the reformed gas in the heating chamber and then releasing the reformed gas; the pipeline is used for conveying the reformed gas from the outlet of the chamber to the reformed gas hydrogen separation device; and the hydrogen storage device is used for storing hydrogen generated by the device.

Description

Technical Field

[0001] This application claims priority to U.S. Provisional Application No. 63 / 414,403, filed Oct. 7, 2022, and U.S. Patent Application No. US18 / 114,175, filed Feb. 24, 2023, the entire contents of which are incorporated herein by reference.

[0002] The present invention relates to the field of gasification, and more particularly, to the production of syngas and hydrogen by pyrolyzing waste such as municipal solid waste with or without biomass.

[0003] Throughout this document, unless otherwise stated, hydrogen refers to dihydrogen (H2).

[0004] Unless otherwise stated, the term "organic matter" related to a substance or product shall be construed as an organic compound in a broad sense, i.e., a product or substance containing carbon that forms covalent bonds. Background Art

[0005] Hydrogen can be used as an energy carrier, for example, to generate electricity in a fuel cell and power the motor of an electric vehicle or any electrical appliance without emitting greenhouse gases (GHGs) such as CO2.

[0006] However, as of the filing date of this application, 96% of hydrogen is produced by reforming fossil fuel natural gas without carbon capture, resulting in atmospheric emissions in the form of greenhouse gases that are approximately nine times the weight of the hydrogen produced.

[0007] So-called green hydrogen can be produced by electrolyzing water. However, when comparing the electrical energy used for electrolysis with the electrical energy released by a fuel cell, its yield is very low, approximately 35%; if the hydrogen needs to be transported and compressed to, for example, 700 bar (10290 Psi), considering the energy required for compression, the yield is even lower.

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

[0009] According to this method, pyrolysis gas is produced by pyrolyzing biomass and further reformed to prepare syngas, which is a gas mixture of CO, H2O, CO2, CH4, and H2, from which hydrogen can be selectively extracted by methods such as Pressure Swing Absorption (PSA).

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

[0011] This reaction occurs at high temperatures, such as 800 °C to 1000 °C (1472 °F to 1832 °F). It is an endothermic reaction, meaning the reaction consumes heat and requires a heat source to support it.

[0012] For example, in a traditional gasifier, just enough air or pure oxygen is provided to reach the required gasification temperature, and the gasification reaction is maintained by burning a portion of the feedstock, thereby generating this heat, which is called the partial oxidation process.

[0013] Although biomass combustion emits greenhouse gases, these greenhouse gases are in non-fossil form and can be recaptured by biomass within a short cycle. However, this combustion process actually burns the fuel / feedstock, so a balance must be found between the required gasification temperature and the amount of feedstock consumed to generate the required heat. Therefore, the partial oxidation process "consumes" part of the feedstock, reducing the possibility of producing hydrogen from this feedstock.

[0014] According to another embodiment of the prior art, the feedstock is heated by a heat carrier such as a solid medium (such as sand or ceramic beads).

[0015] This method is disclosed in document WO 2021 / 221164. The heat carrier medium is heated in a preheating device and then contacts the feedstock made of biomass to heat it, thereby pyrolyzing it through heat exchange.

[0016] The pyrolysis gas reformer partially burns a portion of the gas produced by pyrolysis by supplying oxygen or air. To control combustion and temperature, the reformer implementing this method includes two valves. The first valve controls the continuous supply of air or oxygen, and the second valve provides an intermittent supply of air or oxygen to the reformer.

[0017] Although this device is effective in extracting hydrogen from biomass feedstock, its efficiency in terms of energy consumption is relatively low, especially because preheating the heat carrier requires energy. Additionally, its input efficiency is also low, requiring expensive equipment such as heat carrier feeding, collection, carbon separation, and heating systems, as well as a complex valve system.

[0018] Another system of the prior art uses plasma at a temperature of about 4000 °C to gasify the feedstock. This technical solution not only requires a huge investment but also has a very high maintenance cost because the inner wall of the reactor needs to withstand a relatively high temperature. Summary of the Invention

[0019] The present invention aims to solve the disadvantages of the prior art and provides a system for extracting hydrogen from chemical organic feedstock, including:

[0020] An organic waste feeding unit;

[0021] A spiral pyrolysis gasifier, including a first end and a second end, supplies chemical organic raw materials at the raw material inlet of the first end. The pyrolysis gasifier is configured to heat the organic raw materials to a temperature of at least 800 °C, while conveying the chemical organic raw materials from the first end to the solid residue outlet at the second end through a spiral in the gasification chamber, and collecting pyrolysis gas at the pyrolysis gas collector;

[0022] A first pipeline for conveying pyrolysis gas from the pyrolysis gas collector to the pyrolysis gas inlet of a high-temperature reformer. The high-temperature reformer exposes the pyrolysis gas to a temperature between 1200 °C and 1400 °C, and releases high-temperature reformed gas through the reformed gas outlet;

[0023] A second pipeline conveys the reformed gas from the reformed gas outlet to the reformed gas inlet of the heating chamber of the spiral pyrolysis gasifier. The heating chamber is located between the outer shell of the gasification chamber and the shell of the spiral pyrolysis gasifier and is provided with a chamber outlet to release the reformed gas from the reformed gas inlet to the chamber outlet after circulating in the heating chamber;

[0024] A third pipeline conveys the reformed gas from the chamber outlet to the reformed gas hydrogen separation device; and

[0025] A hydrogen storage device for storing the hydrogen generated by the device.

[0026] Thus, this system neither uses a solid heat carrier in direct contact with the raw materials nor uses partial oxidation, but uses the heat of the reformed gas generated by the high-temperature reformer to indirectly heat the organic raw materials in the spiral pyrolysis gasifier, thus eliminating all the devices required for heating, circulating, and cleaning the solid heat carrier medium in the prior art, and also avoiding the waste of hydrogen precursors due to the oxidation process. The spiral for conveying organic raw materials in the pyrolysis gasifier can precisely control the flow rate of the organic raw materials passing through the pyrolysis gasifier, achieve perfect mixing of the organic raw materials, and improve the heat exchange with the wall of the gasification chamber heated by the heating chamber. Therefore, the heat of the reformed gas that needs to be cooled anyway before hydrogen separation is recovered in the pyrolysis gasifier, further heating the organic raw materials to a temperature as high as 800 °C and above, thereby increasing the conversion rate of the organic raw materials into the mixed gas, and there is very little solid residue.

[0027] The present invention is implemented according to the preferred embodiments disclosed below, and these embodiments can be applied alone or in any technically operable combination.

[0028] In one embodiment, the spiral pyrolysis gasifier includes two parallel helices that rotate and convey organic raw materials from the first end to the second end in opposite directions in a first gasification chamber and a second gasification chamber respectively. The spiral pyrolysis gasifier further includes a connection channel connecting the first gasification chamber and the second gasification chamber. This embodiment makes the design of the spiral pyrolysis gasifier more compact, increases the heat transfer from the heating chamber to the organic raw materials in the gasification chamber, improves the mixing of the organic raw materials, and further enables better control of the flow rate of the organic raw materials introduced into the pyrolysis gasifier.

[0029] Preferably, at least one of the organic waste feeding unit and the raw material inlet includes a rotary air lock. This setting enables continuous feeding of the device during use.

[0030] In one embodiment, the spiral pyrolysis gasifier includes a steam injection inlet for injecting steam into the gasification chamber. Since the high temperature reached in the pyrolysis gasifier is higher than 800 °C, the steam reacts with the carbon in the organic raw materials, thereby further increasing the hydrogen production.

[0031] Preferably, the reformed gas hydrogen separation device includes a carbon capture and storage unit. Therefore, the production of hydrogen using the system of the present invention is at least carbon neutral and can even be carbon negative.

[0032] In a preferred embodiment, the carbon capture and storage unit includes the mineralization of carbon dioxide in an aqueous salt solution and includes the formation of carbonate (CO3 -2 )). This embodiment makes the device carbon negative.

[0033] Preferably, the high-temperature reformer includes an oxy-fuel burner configured to raise the temperature inside the high-temperature reformer.

[0034] Preferably, the oxy-fuel burner is supplied with the tail gas discharged from the reformed gas hydrogen separation device.

[0035] According to the first embodiment, the reformed gas hydrogen separation device includes the production of 5.0 grade pure hydrogen (H2), and the tail gas contains at least 60% carbon monoxide (CO) and at least 15% hydrogen by volume.

[0036] According to a preferred embodiment, in the reformed gas hydrogen separation device, the reformed gas is introduced into a CO shift water gas shift reactor to produce a WGSR treated gas. This WGSR treated gas does not contain carbon monoxide and further increases the hydrogen content at the WGSR outlet.

[0037] According to the first variant embodiment, the WGSR treated gas is introduced into a pressure swing adsorption CO2 separator and then into a pressure swing adsorption device, and the tail gas supplied to the oxy-fuel burner is hydrogen. This embodiment provides a zero-emission but self-sustainable high-temperature reformer.

[0038] According to the second modified embodiment, the WGSR treated gas is introduced into the membrane reactor for hydrogen separation, and before entering the membrane reactor, the WGSR treated gas is heated by heat exchange with the reformed gas generated by the high-temperature reformer.

[0039] According to one embodiment, the first pipeline includes an expansion reactor located between the pyrolysis gas collector and the pyrolysis gas inlet.

[0040] The expansion reactor includes a reactor steam inlet configured to inject steam into the pyrolysis gas in the expansion reactor.

[0041] Preferably, the expansion reactor includes a mixing chamber configured to promote the mixing of the pyrolysis gas and the steam by turbulent flow through the mixing chamber, thereby increasing the hydrogen content.

[0042] Before entering the reformed gas hydrogen separation device, the reformed gas is cooled in the gas conditioning unit, and this cooling is achieved by a heat exchanger that exchanges heat with water.

[0043] The water flowing through the heat exchanger exchanges heat with the reformed gas to generate steam.

[0044] Preferably, the steam is injected into the gasification chamber and the expansion reactor and the WGSR (when the latter exists).

[0045] Preferably, the system further includes a boiler with a burner for further increasing the temperature of the water flowing through the heat exchanger, and the burner is supplied with reformed gas.

[0046] The present invention also provides a method for extracting hydrogen from chemical organic raw materials using the system of the present invention, including the following steps:

[0047] Heating the chemical organic raw material in the pyrolysis gasifier to a temperature of at least 800 °C;

[0048] Collecting the pyrolysis gas from the pyrolysis gasifier and reforming the pyrolysis gas into reformed gas at a temperature of 1200 °C to 1400 °C in the high-temperature reformer; and

[0049] Collecting the reformed gas at the outlet of the high-temperature reformer and introducing the reformed gas into the heating chamber of the pyrolysis gasifier for indirectly heating the chemical organic raw material.

[0050] Preferably, in the steps of heating the organic raw material, reforming the pyrolysis gas, and indirectly heating the organic raw material, the gas pressure is between -30 mmwc and 0 relative to atmospheric pressure.

[0051] According to one embodiment, the method of the present invention further includes the step of converting carbon monoxide in the reformed gas in a water gas shift reactor, and the step of compressing the reformed gas to a pressure of 10 bar to 20 bar before entering the water gas shift reactor.

[0052] Preferably, the method of the present invention further includes the step of separating hydrogen from the reformed gas, and the step of increasing the pressure of the reformed gas to between 20 bar and 30 bar before the step of separating hydrogen.

[0053] In a preferred embodiment, from the step of collecting the pyrolysis gas to the step of separating hydrogen, the gas pressure gradually increases without passing through an expansion step. BRIEF DESCRIPTION OF THE DRAWINGS

[0054] Hereinafter, with reference to Figures 1 - 6 , the present invention is disclosed by preferred embodiments and is in no way limited, wherein:

[0055] Figure 1 is a schematic diagram of the system of the present invention;

[0056] Figure 2 shows a schematic diagram of the gas regulation unit between the pyrolysis reforming unit and the hydrogen separation unit;

[0057] Figure 3A is a simplified longitudinal section of an exemplary embodiment of a spiral pyrolysis gasifier;

[0058] Figure 3B is a simplified longitudinal section of an expander in one embodiment;

[0059] Figure 4 An exemplary embodiment of a high-temperature reformer is shown according to a simplified longitudinal section;

[0060] Figure 5 is a structural diagram of a hydrogen separation device;

[0061] Figure 6 shows Figure 5 a variation of the device shown, wherein hydrogen separation is carried out by a membrane reactor. DETAILED DESCRIPTION OF THE INVENTION

[0062] As Figure 1 shown, according to an exemplary embodiment, the system of the present invention includes an organic waste feeding unit 100 having a hopper 102 and a hopper loader 101 for loading a chemical organic raw material into the system.

[0063] The chemical organic raw materials consist of waste materials or wastes composed of organic compounds containing fixed carbon. The system is very flexible and can accept raw materials with an ash content preferably maintained below 5%, and can also accept raw materials with an ash content up to 30%. The water content range of the raw materials can be between 5% and 30%, but is preferably around 15%.

[0064] As a non-limiting embodiment, the chemical organic raw materials include plant-based biomass, such as wood chips, sawdust, construction waste wood, pruned branches, forest residues, unused trees, crop residues (such as discarded vegetables and fruits), straw, wheat straw, rice husks, marine plants, algae, fishery residues, biomass (such as livestock manure, sewage sludge, fertilizers), organic municipal solid waste (such as garbage containing cardboard, plastics, and food waste), and any combination of the above substances.

[0065] To ensure the operation of the system under its acceptable conditions, the raw materials need to be pretreated at the site and / or at more remote waste collection plants.

[0066] Basically, more specifically, when the raw materials contain municipal waste, the raw materials need to be sorted to screen out inorganic materials such as metals, glass, or cement, and then the sorted raw materials are crushed. The water content can be adjusted by mixing raw materials from different sources (such as raw materials with low water content and raw materials with high water content).

[0067] This pretreatment can keep the ash and water content of the raw materials within an appropriate range to ensure the performance of the system of the present invention.

[0068] When feeding the chemical organic raw materials into the gasification reforming device 160, they are first fed into the spiral pyrolysis gasifier 110 through the raw material inlet with the first rotary air lock 103. The first rotary air lock 103 can prevent the pyrolysis gas from escaping from the gasification chamber 118 of the pyrolysis gasifier during feeding, so that discontinuous and / or continuous feeding of the gasification reforming device can be achieved during use.

[0069] According to an exemplary and illustrative embodiment, the spiral pyrolysis gasifier includes a spiral body 115, which is driven by a driver 116 located outside the gasification chamber and can rotate within the gasification chamber 118. The spiral body pushes the organic raw materials from the first end 111 to the second end 112 of the pyrolysis gasifier at a controlled speed defined by its pitch and rotational speed.

[0070] The spiral pyrolysis gasifier further includes a heating chamber 119 separated from the gasification chamber 118 by a wall body serving as an inner wall. The heating chamber heats the inner wall of the gasification chamber 118, and as the organic raw materials travel from the first end 111 to the second end 112 of the pyrolysis gasifier and contact the inner wall of the gasification chamber 118, their temperature gradually increases.

[0071] The temperature of the chemical organic raw material rises from room temperature at the outlet of the feeding unit 100 to 800 °C (1472 °F), and can even rise to 900 °C (1652 °F) in the gasification chamber 118, preferably maintained at around 850 °C (1562 °F).

[0072] In fact, the pyrolysis gasifier provides a large surface for heat exchange with the inner wall, and drives the raw material through a spiral, enabling the raw material to come into full contact with and be continuously mixed with this surface, thereby achieving rapid and uniform heating of the raw material.

[0073] According to one embodiment, the spiral pyrolysis gasifier 110 includes a steam injection inlet 313 for injecting steam from the steam pipeline 113 into the gasification chamber 118, but the steam is more preferably injected into the expansion reactor 120 at the outlet of the spiral pyrolysis gasifier.

[0074] The steam / water comes from the moisture contained in the organic raw material and the steam injected into the gasification chamber 118 through the steam injection inlet 313 via the steam pipeline 113. Therefore, the amount of steam injected into the gasification chamber depends on the nature of the organic raw material and its moisture content.

[0075] The spiral pyrolysis gasifier 110 is collected by the pyrolysis gas mainly containing CO, H2O, CO2, CH4, H2 and a small amount of other gases generated during the gasification process through the pyrolysis gas collector 117, and is transported to the high-temperature reformer 130 through pipelines 121 and 125.

[0076] According to a preferred embodiment, the first pipeline 121 for transporting the pyrolysis gas from the chamber outlet of the spiral pyrolysis gasifier 110 to the high-temperature reformer 130 includes a gas expansion reactor 120, in which the pyrolysis gas is further mixed with the steam from the steam pipeline 113, and the steam-rich pyrolysis gas is transported to the high-temperature reformer 130 through the second pipeline 125.

[0077] The gas expansion reactor, by virtue of its inherent volume, additionally provides a means to maintain a stable negative pressure in the gas passage from the pyrolysis gasifier to the downstream gas separator.

[0078] The spiral pyrolysis gasifier 110 is provided with a solid residue outlet 114 at the second end 112 for collecting the solid residues generated by the pyrolysis of the raw material, namely ash and carbon black. The operating conditions of the pyrolysis gasifier can be adjusted to produce less or more carbon black.

[0079] In a preferred embodiment, the temperature in the gasification chamber is high enough (i.e., 850 °C or higher) to avoid the formation of carbon black, so that only ash can be collected at the solid residue outlet 114. In another embodiment, when carbon black needs to be formed, the carbon black is conveyed by a carbon black conveyor 122 to the carbon black inlet of the high-temperature reformer 130. The ash 105 is collected and transported for off-site treatment. The carbon black and ash can also be used as fertilizers, thus promoting carbon capture through biomass.

[0080] In the high-temperature reformer, the temperature of the pyrolysis gas is at least 1200 °C (2192 °F), preferably reaching 1400 °C (2552 °F).

[0081] Such a high temperature is achieved by the heat provided by an oxy-fuel burner 135. The burner is supplied with oxygen by an oxygen pipeline 133 and releases tail gas 193 at the hydrogen separation unit 190. The oxygen pipeline 133 is supplied with oxygen by an oxygen production device 182, which produces oxygen from air by a method such as cryogenic separation.

[0082] According to the first embodiment, the tail gas contains 60% CO and at least 15% H2.

[0083] As Figure 5 shown, according to a preferred embodiment, the tail gas is actually H2, which is collected at the outlet of the hydrogen separation unit.

[0084] In any embodiment, the tail gas 193 does not come into contact with air during the combustion process in the oxy-fuel burner 135, thus reducing or even avoiding nitrogen oxide (NOx) emissions. Moreover, according to the preferred embodiment, when the tail gas is hydrogen, the combustion process is clean, mainly producing steam, which promotes the recovery of downstream hydrogen and can avoid the increase of undesired carbon compounds in the reformed gas.

[0085] The high-temperature reformer 130 produces a gas called reformed gas, which is rich in free H2 and has a high temperature.

[0086] The reformed gas 150 leaves the high-temperature reformer 130 through the reformed gas outlet 134 and is conveyed through the heating pipeline 124 via the reformed gas inlet to the heating chamber 119 of the spiral pyrolysis gasifier for circulation. Therefore, the heat of the reformed gas is advantageously used to increase the temperature of the raw material. In the preferred embodiment, most of the ash in the pyrolysis gas is removed by a particle filter at the outlet of the pyrolysis gasifier in the spiral pyrolysis gasifier stage. However, in a specific embodiment, the reformed gas can first pass through an additional particle separator 140 before being introduced into the heating chamber 109 of the spiral pyrolysis gasifier.

[0087] According to this specific embodiment, the ash 141 separated from the reformed gas is recovered and processed.

[0088] The following reactions occur in the gasification reforming device:

[0089] - The available oxygen in the organic raw material undergoes partial oxidation with carbon: C + O2 → CO2

[0090] - Steam gasification: C + H2O → CO + H2

[0091] - Methanation: C + 2H2 → CH4

[0092] - Boudouard reaction: C + CO2 → 2CO

[0093] - Water-gas shift reaction: CO + H2O → CO2 + H2

[0094] - Methane reforming reaction: CH4 + H2O → CO + 3H2

[0095] - Acid production: H2 + Cl2 → 2HCl and H2 + S → H2S

[0096] The reformed gas is discharged from the heating chamber of the spiral pyrolysis gasifier through the chamber outlet and is guided to the reformed gas conditioning unit 170 before entering the hydrogen separation device.

[0097] Therefore, before entering the hydrogen separation device, it is preferable to cool the reformed gas and further treat pollutants (as Figure 2 shown) to obtain the conditioned reformed gas.

[0098] As an exemplary embodiment, hydrogen is separated from the conditioned reformed gas by the hydrogen separation unit 191, which includes a pressure swing adsorption (PSA) device connected to the carbon capture and storage unit 180.

[0099] Those skilled in the art understand that using a PSA unit to separate hydrogen from the reformed gas is only an exemplary embodiment, and other separation methods, such as membrane separation or cryogenic separation, can also be considered without changing the principle of the present invention.

[0100] The reformed gas should be cleaned and cooled before entering the hydrogen separation unit. Therefore, the reformed gas is at least partially cooled by flowing through the heating chamber 119 of the spiral pyrolysis gasifier 110. During this process, the reformed gas flows through the jacket wall of the pyrolysis gasifier to exchange heat with the organic raw material, but does not come into direct contact.

[0101] The hydrogen produced by the hydrogen separation unit is stored in the storage tank 192, specifically in a pressurized tank with a pressure of 300 bar to 700 bar to reduce the storage volume. Alternatively, according to a variant, it can also be liquefied or stored in a dry adsorption medium (such as metal hydride).

[0102] The carbon capture and storage unit 180 processes carbon dioxide and stores the carbon in the form of carbonate 181.

[0103] As an exemplary embodiment, the carbon capture and storage unit (180) is provided by a Norwegian company (address: Solheimsgaten 16, 5058 Bergen), where carbon dioxide is mineralized in an aqueous solution of 183 Ca(OH)2. After drying, it can be processed, for example, buried or sold for specific uses.

[0104] As Figure 2 shown, a part of the cooled reformed gas 151 is sent to the gas conditioning unit 170 through the third pipeline and is first introduced into a quenching unit 271 with water 213 to reduce its temperature.

[0105] According to an embodiment, the reformed gas passes through a scrubber 273 and a fine particle filter 272.

[0106] The scrubbing process can remove hydrogen chloride, hydrogen sulfide and other corrosive components from the reformed gas.

[0107] The filter 272 can remove extremely fine ash from the reformed gas, and these ashes will be collected and processed.

[0108] The reformed gas is preferably further cooled before entering the scrubber. For this purpose, before entering the scrubber, the reformed gas is cooled by a heat exchanger 275 filled with water 213. In the heat exchanger, water is converted into steam, which is then further supplied through the steam pipeline 113 to the equipment in the device that consumes steam, such as the reformer, the expansion reactor and the screw pyrolysis gasifier.

[0109] When the device is started, the flow rate of the reformed gas may not be sufficient to generate enough steam through the heat exchanger 275. For this reason, the device also includes a boiler 211 with a boiler burner 209.

[0110] The reformed gas, or liquefied petroleum gas via the liquefied petroleum gas (LPG) pipeline 210, can be supplied to the boiler burner 209, and the latter is only used for starting the device.

[0111] From the pyrolysis gasification reforming device 160 to the inlet of the reformed gas conditioning unit 170, the device operates under a slight negative pressure of -30 to 0 mmwc (millimeters of water column) relative to the atmospheric pressure, preferably between -30 and -10 mmwc. At the outlet of the filter 272, before entering the hydrogen separation unit, the pressure of the conditioned reformed gas is increased to 10 to 20 bar, preferably about 15 bar, by a compressor 276.

[0112] The reformed gas regulating unit 170 releases the regulated reformed gas 251, which is sent to the hydrogen separation unit.

[0113] According to an exemplary embodiment (not shown), the system consists of a plurality of stackable and connectable 20-foot ISO containers and can be assembled.

[0114] All components are positioned and fixed in their respective containers, and the containers have sufficient stiffness to support all components and their own weight.

[0115] Therefore, the installation of the system mainly includes connecting pipelines and containers. The containers form the structural framework of the installation and can be laid on a concrete slab or a steel truss on site.

[0116] For this purpose, the components are designed to be as compact as possible.

[0117] As Figure 3A shown, according to an embodiment, the pyrolysis gasification unit is contained in a container located above the container containing the reforming unit.

[0118] According to this embodiment, the screw pyrolysis gasifier 110 is generally tubular, horizontally placed, and includes a first end and a second end and means for conveying the raw material introduced at the first end to the second end.

[0119] As an exemplary embodiment, the screw pyrolysis gasifier 110 includes two parallel screws 3151, 3152; as means for conveying the raw material, each screw is mounted between two bearings 3511, 3512 driven by two electric drives 3161, 3162. Compared with a rotary kiln, the advantage of the screw pyrolysis gasifier 110 is that the bearings and the corresponding seals are located outside the high-temperature zone, and the bearings can be cooled without affecting the operation of the equipment, thereby reducing costs; at the same time, the use of lip seals can be avoided, and lip seals may leak reformed gas into the atmosphere.

[0120] The two screws 3511, 3512 push the raw material in opposite directions, and the total length of their travel is about twice the total length of the pyrolysis gasifier 110, so that its structure is more compact.

[0121] Each screw 3511, 3512 may have a single-thread or multi-thread with a constant or variable pitch along its length, and the two screws may have different pitches and different pitch variations. One or both of the screws may be tapered.

[0122] Each screw rotates in the gasification chambers 3181 and 3182 respectively, and the two gasification chambers are connected by a connecting channel 322. Thus, after the raw material is fed into the screw pyrolysis gasifier 110 through the feed hopper 303 located at the first end (feed end) of the first gasification chamber, it is driven by the first screw towards the other end of the first gasification chamber; when it falls into the first end of the second gasification chamber 3182 through the connecting channel 311, it is driven by the second screw 3152 towards the other end (collection end) of the second gasification chamber.

[0123] According to a preferred embodiment, the feed hopper located at the raw material inlet of the pyrolysis gasifier includes a second rotary air lock 304.

[0124] This latter rotary air lock 304 can be used alone or in combination with the first rotary air lock 103 located upstream of the feed hopper to provide continuous feeding to the device while preventing the pyrolysis gas from escaping through the feed port. For this purpose, the feed hopper 303 preferably includes one or more sensors 3030, such as load cells or filling level sensors, to control the feeding of the raw material during operation.

[0125] In the present exemplary embodiment, the gasification chamber is cylindrical with a circular cross-section. However, the cross-section of the gasification chamber can also be, for example, elliptical, and one or both gasification chambers can extend in a conical shape to match the shape, cross-section, thread, pitch, and pitch variation of the screw conveyors. As an exemplary embodiment, the walls of the gasification chamber are heated by tubular ducts 3191, 3192 arranged around each gasification chamber for conveying high-temperature reformed gas.

[0126] The tubular ducts and the walls of the gasification chamber are made of, for example, ceramics (such as aluminum nitride) or a nickel-based alloy with high-temperature resistance, the surface of which is coated with a highly thermally conductive ceramic such as aluminum nitride, beryllium oxide, silicon carbide, or silicon nitride to resist wear and withstand high temperatures.

[0127] The screw pyrolysis gasifier includes an annular housing 350 and a heat insulation layer 351 located between the housing and the gasification chamber and between the gasification chambers.

[0128] According to another embodiment, the heating chamber is formed by the interlayer space between the inner gasification chamber wall and the outer surrounding wall, and the high-temperature reformed gas directly circulates in this interlayer space without being conveyed through the tubular ducts.

[0129] The screw pyrolysis gasifier and the entire pyrolysis reforming unit operate at atmospheric pressure or slightly negative pressure, so they do not require an excessive thickness to withstand high pressure.

[0130] According to the water content of the raw material, if necessary, steam can be injected into the first gasification chamber 3181 from the steam pipeline 113 through the steam inlet 313.

[0131] As the raw material moves from the feed end to the discharge end under the drive of the spiral, the organic raw material (mixed with steam if applicable) will gasify according to the above chemical reaction. On the one hand, it is converted into solid residues, namely carbon and ash, which are collected at the collection end through one or more solid residue outlets 314; on the other hand, it is converted into gas, called pyrolysis gas, which is essentially syngas and is collected through the pyrolysis gas outlet 321.

[0132] The operating conditions of the system can avoid the generation of carbon black. However, if, for example, due to the nature of the raw material, the optimal conditions cannot be achieved, or during the startup of the system, a small amount of carbon black may be generated, and this carbon black will be collected at the solid residue outlet 314. In a preferred embodiment, it will also be further sent to the high-temperature reformer through a carbon black conveyor. The ash will be transported for off-site treatment. Optionally, the carbon black can also be transported for off-site treatment.

[0133] The pyrolysis gas is collected in two gasification chambers through pipelines and then introduced into the expansion reactor 120, where it is mixed with steam and then transported to the high-temperature reformer.

[0134] When the spiral pyrolysis gasifier is placed horizontally, the pyrolysis gas is collected at the top of the spiral pyrolysis gasifier, and the solid residues are collected at the bottom of the pyrolysis gasifier, and the raw material moves along the horizontal axis.

[0135] As Figure 3B shown, the expansion reactor 120 is preferably located near and connected to the spiral pyrolysis gasifier, thus forming a compact device.

[0136] The expansion reactor includes a housing 360 with a heat insulator 361, and its inner wall is made of or coated with ceramics.

[0137] Preferably, the pyrolysis gas leaving the spiral pyrolysis gasifier enters the expansion reactor 120 through a particulate filter 325 located at the pyrolysis gas inlet 320.

[0138] The expansion reactor can maintain the pressure in the entire device up to the CO2 separation stage close to atmospheric pressure, preferably slightly negative pressure, usually in the range of -10 to -30 mmwc, and allows steam to be injected into the pyrolysis gas released to the pyrolysis gasifier. The steam is injected from the steam pipeline 113 through the Venturi effect.

[0139] The expansion reactor contains a mixing chamber 301, where the injection of steam promotes turbulence in the pyrolysis gas stream, enhancing the mixing and reaction of steam and pyrolysis gas. The steam also provides an additional hydrogen source for the pyrolysis gas, and at the same time, the expansion reactor provides residence time and space for the occurrence of gaseous reactions.

[0140] The pyrolysis gas escapes from the expansion reactor through the pyrolysis gas outlet 321 and is directed to the high-temperature reformer.

[0141] When the system is arranged in a stacked container, the container containing the high-temperature reformer should be arranged below the container containing the screw pyrolysis gasifier and the expansion reactor.

[0142] As Figure 4 shown, according to an exemplary embodiment, the high-temperature reformer 130 is horizontally arranged and includes a housing 460, a heat insulation layer 461 and a ceramic lining. The steam-rich pyrolysis gas discharged from the expansion reactor enters the high-temperature reformer from one end through the pyrolysis gas inlet 421, and the carbon black (if any) can be conveyed to the carbon black inlet 414 through the carbon black conveyor 122. The steam-rich pyrolysis gas entering the high-temperature reformer through the second pipeline 125 is enriched in steam content by steam injection in the expansion reactor.

[0143] The tail gas 193 is supplied to the oxy-fuel burner 135. The tail gas 193 is the tail gas containing H2 and CO of the hydrogen separation unit, or, according to a preferred embodiment, a part of the H2 generated by the hydrogen separation unit, and this part of H2 is collected and conveyed through a pipeline accordingly. The oxy-fuel burner is supplied with industrial-grade oxygen. Therefore, air is not involved in the combustion process and nitrogen oxides (NOx) are not generated.

[0144] The combustion process generates a high-temperature flame 435 inside the reformer, raising the temperature inside it to 1400 °C.

[0145] The reformed gas 150 leaves the high-temperature reformer through the reformed gas outlet 434, and the solid residue is collected at the bottom of the reformer through the ash outlet 440 with a rotary valve air lock 403. The ash is then transported to off-site for treatment.

[0146] As described above, before being adjusted and sent to the hydrogen separation unit, the reformed gas 150 will first be sent to the particle cleaning stage, and a part of it will pass through the heating chamber of the screw pyrolysis gasifier before entering the reformed gas conditioning unit.

[0147] As Figure 5 shown, according to a preferred embodiment, the adjusted reformed gas 251 rich in H2 but still containing CO, CO2 and N2 discharged from the reformed gas conditioning unit 170 first enters the CO conversion water gas shift reactor (WGSR) 591.

[0148] The WGSR contains a catalytic medium and uses the steam injected from the steam pipeline 113 to react with the carbon monoxide in the reformed gas to generate hydrogen and carbon dioxide. The WGSR 591 can completely remove carbon monoxide and significantly increase the hydrogen content in the reformed gas. The WGSR operates under positive pressure, usually about 15 bar.

[0149] After leaving the WGSR 591, the WGSR treated gas 595 containing CO2, H2, and nitrogen N2 is filtered through a filtration and compression unit 592 with an ultra-fine filter and a screw compressor, compressed by the compressor to a pressure of 20 to 30 bar, and then enters a CO2 pressure swing adsorption separator (PSA) 593.

[0150] The PSA separates 100% of the carbon dioxide, forming a PSA treated gas 551 that only leaves hydrogen and nitrogen, which then enters a pressure swing adsorption device (PSA) 590 for separating H2.

[0151] CO2 194 is introduced into the carbon capture and storage unit 180, where carbon treatment is carried out and stored as a solid medium. At the same time, other gases mainly composed of hydrogen are used to supply the oxy-fuel burner.

[0152] The hydrogen produced by the PSA device 590 meets the ISO 14687 Class D specification and is suitable for PEM fuel cells.

[0153] Hydrogen is stored in a storage tank 192, for example, in a pressure tank. At the same time, a part of it is collected and sent out as "tail gas" 193, which is actually H2 and is used to supply the oxy-fuel burner.

[0154] Therefore, according to this preferred embodiment, from the overall perspective of the system, the only gaseous atmospheric emissions consist only of steam and nitrogen.

[0155] As Figure 6 shown, according to an alternative embodiment, hydrogen separation is carried out through a membrane reactor 690, for example, through a palladium membrane reactor.

[0156] According to this embodiment, the WGSR treated gas 595 is first guided through a heat exchanger 691, where it is heated to a temperature at which a reaction can occur in the membrane reactor 690.

[0157] According to an exemplary embodiment, the heating is achieved by heat exchange with the reformed gas 151 from a high-temperature reformer, and this gas is further introduced into a heating pipe 124 to heat the heating chamber of the spiral pyrolysis gasifier.

[0158] The membrane reactor 690 separates the WGSR treated gas 595 into a CO2-rich stream 694 and fuel cell-grade hydrogen 692. Among them, the CO2-rich stream is sent to the carbon capture and storage unit, and the fuel cell-grade hydrogen is sent to the storage tank 192, and a part of it, 193, is used to supply the oxy-fuel burner.

[0159] Compared with Figure 5 the embodiment shown, the latter embodiment has less investment and can increase the production of H2 by 50%.

[0160] As shown above, regardless of the implementation method, the gas pressure in the device gradually increases from atmospheric pressure to the hydrogen separation pressure and finally reaches the storage pressure. Therefore, the gas does not need to undergo an energy-consuming compression and expansion cycle process.

[0161] Example 1

[0162] The following table shows a non-limiting implementation of the material flow according to the first embodiment, in which the tail gas supplied to the oxy-fuel burner mainly contains CO and H2.

[0163] Although the system can convert various chemical organic raw materials including municipal waste, the raw material considered in this embodiment is wood chips.

[0164] Once the steady state is reached, the system can produce approximately 39 kg of hydrogen per hour, which is equivalent to a potential energy of 1.3 MWh per hour, and has the ability to self-sustain.

[0165] A part of the generated hydrogen can be used in a fuel cell to generate the electricity required by the system, for example, to drive a screw pyrolysis gasifier.

[0166] Table 1

[0167]

[0168]

[0169] Example 2

[0170] In this Example 2, H2 from the pressure swing adsorption device is supplied to the oxy-fuel burner.

[0171] The raw material is wood chips, and the main components involved in the process are shown in Table 2.

[0172] Table 2

[0173]

[0174]

[0175] In the steam pipeline 113, steam is injected at a pressure of 10 bar (gauge pressure) and a temperature of 175 °C to supply steam to the steam-using equipment (such as the expansion reactor 120, the high-temperature reformer 130, and the WGSR 591).

[0176] Table 3 lists the main processes between different stages of the device.

[0177] Table 3

[0178]

[0179]

[0180] Generally speaking, in this configuration, the system produces hydrogen meeting the ISO 14687 Class D standard at 69 Kg / h, while producing H2 mixed with trace amounts of CO2 and N2 at 102 Kg / h, which can be used for combustion or fed into a second PSA unit to further extract fuel cell grade H2.

[0181] According to the above embodiment, 22.48 Kg / h of PSA grade H2 is used to supply the oxy-fuel burner.

[0182] The composition of the pyrolysis gas is shown in Table 4.

[0183] Table 4

[0184] Component wt% Mol% / Vol% Carbon monoxide (CO) 37.71％ 21.75％ <![CDATA[Carbon dioxide (CO2)]]> 30.09％ 11.04％ <![CDATA[Hydrogen (H2)]]> 6.31％ 50.72％ Tar 10.55％ 2.84％ <![CDATA[Nitrogen (N2)]]> 0.82％ 0.47％ Hydrochloric acid (HCl) 0.42％ 0.19％ <![CDATA[Hydrogen sulfide (H2S)]]> 0.44％ 0.21％ <![CDATA[H2O]]> 8.94％ 8.02％ <![CDATA[Methane (CH4)]]> 4.71％ 4.76％ Total 100.00％ 100.00％

[0185] The composition of the reformed gas at the outlet of the high-temperature reformer is shown in Table 5.

[0186] Table 5

[0187] Component wt% Mol% / Vol% Carbon monoxide (CO) 50.50％ 25.59％ <![CDATA[Carbon dioxide (CO2)]]> 22.18％ 7.15％ <![CDATA[Hydrogen (H2)]]> 7.36％ 51.94％ Tar 0.00％ 0.00％ <![CDATA[Nitrogen (N2)]]> 0.60％ 0.31％ Hydrochloric acid (HCl) 0.31％ 0.12％ <![CDATA[Hydrogen sulfide (H2S)]]> 0.32％ 0.13％ <![CDATA[H2O]]> 18.72％ 14.75％ <![CDATA[Methane (CH4)]]> 0.00％ 0.00％ Total 100.00％ 100.00％

[0188] The composition of the gas after WGSR treatment is shown in Table 6. It should be noted that the gas entering the WGSR unit has passed through the gas conditioning unit 170.

[0189] Table 6

[0190] Component wt% Mol% / Vol% Carbon monoxide (CO) 2.26％ 1.17％ <![CDATA[Carbon dioxide (CO2)]]> 87.49％ 28.78％ <![CDATA[Hydrogen (H2)]]> 9.68％ 69.75％ Tar 0.00％ 0.00％ <![CDATA[Nitrogen (N2)]]> 0.54％ 0.28％ Hydrochloric acid (HCl) 0.00％ 0.00％ <![CDATA[Hydrogen sulfide (H2S)]]> 0.00％ 0.00％ <![CDATA[H2O]]> 0.02％ 0.01％ <![CDATA[Methane (CH4)]]> 0.00％ 0.00％ Total 100.00％ 100.00％

[0191] The composition of the gas after CO2 VPSA treatment is shown in Table 7.

[0192] Table 7

[0193]

[0194]

Claims

1. A system for extracting hydrogen from chemical organic raw materials, comprising: An organic waste feeding unit; A spiral hot gasifier, including a first end and a second end, with a chemical organic raw material supplied at the raw material inlet at the first end. The hot gasifier is configured to heat the organic raw material to a temperature of at least 800 °C, and at the same time convey the chemical organic raw material from the first end to the solid residue outlet at the second end through a spiral in the gasification chamber, and collect pyrolysis gas at the pyrolysis gas collector; A first pipeline for conveying the pyrolysis gas from the pyrolysis gas collector to the pyrolysis gas inlet of a high-temperature reformer. The high-temperature reformer exposes the pyrolysis gas to a temperature between 1200 °C and 1400 °C and releases high-temperature reformed gas through the reformed gas outlet; A second pipeline for conveying the reformed gas from the reformed gas outlet to the reformed gas inlet of the heating chamber of the spiral hot gasifier. The heating chamber is located between the outer shell of the gasification chamber and the housing of the spiral hot gasifier and is provided with a chamber outlet to release the reformed gas from the reformed gas inlet to the chamber outlet after circulating in the heating chamber; A third pipeline for conveying the reformed gas from the chamber outlet to a reformed gas hydrogen separation device; And A hydrogen storage device for storing the hydrogen generated by the device.

2. The system according to claim 1, wherein, The spiral hot gasifier includes two parallel spirals, which respectively rotate in opposite directions from the first end to the second end in the first gasification chamber and the second gasification chamber and convey the organic raw material. The spiral hot gasifier also includes a connection channel connecting the first gasification chamber and the second gasification chamber.

3. The system according to claim 1, wherein At least one of the organic waste feeding unit and the raw material inlet includes a rotary air lock.

4. The system according to claim 1, wherein The spiral hot gasifier includes a steam injection inlet for injecting steam into the gasification chamber.

5. The system according to claim 1, wherein The reformed gas hydrogen separation device includes a carbon capture and storage unit.

6. The system according to claim 5, wherein the carbon capture and storage unit includes the mineralization of carbon dioxide in an aqueous brine solution and includes the generation of carbonate (CO3 -2 ).

7. The system according to claim 6, wherein The high-temperature reformer includes an oxy-fuel burner configured to raise the temperature inside the high-temperature reformer.

8. The system according to claim 7, wherein, The oxy-fuel burner is supplied with the tail gas discharged from the reformed gas hydrogen separation device.

9. The system according to claim 8, wherein, The reformed gas hydrogen separation device includes the production of 5.0-grade pure hydrogen (H2), and the tail gas contains at least 60% carbon monoxide (CO) and at least 15% hydrogen by volume.

10. The system according to claim 8, wherein, In the reformed gas hydrogen separation device, the reformed gas is introduced into a CO conversion water gas shift reactor to obtain a WGSR treated gas.

11. The system according to claim 10, wherein, The WGSR treated gas is introduced into a pressure swing adsorption CO2 separator and then into a pressure swing adsorption device. The tail gas supplied to the oxy-fuel burner is hydrogen.

12. The system according to claim 10, wherein, The WGSR treated gas is introduced into a membrane reactor for hydrogen separation, and before entering the membrane reactor, the WGSR treated gas is heated by heat exchange with the reformed gas generated by the high-temperature reformer.

13. The system according to claim 1, wherein The first pipeline includes an expansion reactor located between the pyrolysis gas collector and the pyrolysis gas inlet.

14. The system according to claim 13, wherein the expansion reactor includes a reactor steam inlet configured to inject steam into the pyrolysis gas in the expansion reactor.

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

16. The system according to claim 14, wherein, Before entering the reformed gas hydrogen separation device, the reformed gas is cooled in a gas conditioning unit, and this cooling is achieved by a heat exchanger that exchanges heat with water.

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

18. The system according to claim 16, including a boiler having a burner for further increasing the temperature of the water flowing through the heat exchanger, and the burner is supplied with reformed gas.

19. The system according to claim 16, wherein, Steam is injected into the gasification chamber and the expansion reactor.

20. The system according to claim 18, wherein In the reformed gas hydrogen separation device, the reformed gas is introduced into a CO conversion water gas shift reactor to obtain a WGSR treated gas, and steam is injected into the WGSR.

21. A method for extracting hydrogen from a chemical organic raw material using the system according to claim 1, comprising the following steps: Heating the chemical organic raw material in the hot gasifier to a temperature of at least 800 °C; Collecting the pyrolysis gas from the hot gasifier and reforming the pyrolysis gas into reformed gas at a temperature of 1200 °C to 1400 °C in a high-temperature reformer; And Collecting the reformed gas at the outlet of the high-temperature reformer and introducing the reformed gas into the heating chamber of the hot gasifier for indirectly heating the chemical organic raw material.

22. The method according to claim 21, wherein, In the steps of heating the organic raw material, reforming the pyrolysis gas, and indirectly heating the organic raw material, the gas pressure is between -30 mmwc and 0 relative to atmospheric pressure.

23. The method according to claim 22, further comprising the step of converting carbon monoxide in the reformed gas in a water gas shift reactor, and the step of compressing the reformed gas to a pressure of 10 bar to 20 bar before entering the water gas shift reactor.

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

25. The method according to claim 24, wherein, From the step of collecting the pyrolysis gas to the step of separating hydrogen, the gas pressure gradually increases without passing through an expansion step.

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