System and method for hydrogen production coupled with liquid carbon dioxide capture from carbonaceous material gasification

Abstract

The present application relates to a system and method for hydrogen production by gasification of carbon-containing substances coupled with liquid carbon dioxide capture, in which coal, biomass, organic solid waste and other carbon-containing substances are converted into high-pressure hydrogen-rich gas with high hydrogen content by regulating organic matter gasification, carbon monoxide shift and low-carbon hydrocarbon steam reforming reactions in high-pressure gasification reactors at high temperature and high pressure in water, and separated in a high-pressure multiphase separator according to the density differences of the hydrogen-rich gas, liquid carbon dioxide and water, and the liquid carbon dioxide is captured, thereby effectively reducing the energy consumption of carbon dioxide separation. The hydrogen is purified by pressure swing adsorption at high pressure, the adsorbent capacity is large, the processing capacity of the adsorption tower is high, and high-pressure product hydrogen is obtained, which can save investment and reduce energy consumption.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of hydrogen energy preparation, and particularly relates to a system and method for gasification of carbon-containing substances to prepare hydrogen coupled with liquid carbon dioxide capture. BACKGROUND

[0002] Hydrogen energy is paid more and more attention due to its high unit mass heat value and clean combustion. Hydrogen combustion turbine power generation and fuel cell power generation are currently the most efficient and least polluting power generation methods. Hydrogen-fueled vehicles can meet the requirements of high efficiency and zero emissions. From the perspective of sustainable development, hydrogen energy is the ideal energy for human beings in the future. One of the key problems to be solved for the wide use of hydrogen energy is large-scale preparation of hydrogen. China is relatively short of oil and natural gas resources, and rich in coal reserves. Energy endowment determines that hydrogen is prepared on a large scale by taking coal as a raw material. China is the only country in the world that uses coal to prepare hydrogen on a large scale. In 2020, about two-thirds of hydrogen in China was produced from coal hydrogen plants.

[0003] Traditional coal hydrogen production is to first make coal react with oxygen, and then make the coal react with water to obtain a gaseous product (synthesis gas) mainly composed of hydrogen (H2) and carbon monoxide (CO). The relative content of hydrogen in the crude synthesis gas is relatively low. The H2 / CO ratio of synthesis gas in the pulverized coal gasification process is 0.4-0.5, and the H2 / CO ratio of synthesis gas in the coal slurry gasification process is 0.7-1.1. In order to generate more hydrogen, the crude synthesis gas is purified by desulfurization and continues to react with water vapor to generate carbon dioxide and hydrogen from carbon monoxide and water. Taking coal as a raw material to prepare hydrogen will emit a large amount of greenhouse gases during the hydrogen production process. The preparation of 1 ton of hydrogen emits 20.02 tons of CO2. Considering the reduction of CO2 emissions, the total investment of the coal gasification hydrogen production system will increase by 6%-7%, the cost of hydrogen will increase by 29%-33%, and the cost of CO2 reduction is about 170-183 yuan / ton. Large-scale development of hydrogen energy industry must aim at low carbon in the whole life cycle. Therefore, how to prepare hydrogen while capturing carbon dioxide has become a key problem to be solved for large-scale development of hydrogen energy. SUMMARY

[0004] The technical problem to be solved by the present application is to provide a system and method for gasification of carbon-containing substances to prepare hydrogen coupled with liquid carbon dioxide capture, so as to achieve the purpose of capturing carbon dioxide while preparing hydrogen.

[0005] To achieve the above-mentioned purpose, according to one aspect of the present application, a system for gasification of carbon-containing substances to prepare hydrogen coupled with liquid carbon dioxide capture is provided, comprising:

[0006] The high-pressure gasification reactor comprises a metal sintered microporous tube, a reaction shell and a thermal insulation layer; the metal sintered microporous tube is coaxially arranged in the reaction shell, and an annular gap is formed between the outer wall of the metal sintered microporous tube and the inner wall of the reaction shell; and the thermal insulation layer is wrapped outside the reaction shell.

[0007] An end cover is arranged at the upper end surface of the reaction shell, and a raw material slurry feeding pipe is fixed at the center of the end cover; the lower end of the raw material slurry feeding pipe penetrates through the end cover and extends to the upper part of the inner cavity of the metal sintered microporous tube; and an oxygen distribution pipe is arranged in the raw material slurry feeding pipe, and the lower end of the oxygen distribution pipe extends to the middle part of the inner cavity of the metal sintered microporous tube, and the oxygen distribution pipe is connected with the oxygen input pipeline.

[0008] A product discharge pipe is arranged at the lower part of the reaction shell, and the product discharge pipe penetrates through the thermal insulation layer and extends to the outside of the thermal insulation layer; and a slag discharge pipe is arranged at the bottom of the metal sintered microporous tube, and the slag discharge pipe penetrates through the reaction shell and the thermal insulation layer from inside to outside and extends to the outside of the thermal insulation layer.

[0009] The high-pressure pipeline mixer is connected with the raw material slurry feeding pipe through the outlet.

[0010] The heat energy recovery heat exchanger comprises a shell and a heat exchange pipe arranged in the shell; a hot fluid inlet and a hot fluid outlet are arranged at the two ends of the shell respectively, and the two ends of the heat exchange pipe are a cold fluid inlet and a cold fluid outlet respectively.

[0011] The product discharge pipe of the high-pressure gasification reactor is connected with the hot fluid inlet of the heat energy recovery heat exchanger, and the hot fluid outlet of the heat energy recovery heat exchanger is connected with the product inlet of the high-pressure multi-phase separator.

[0012] The high-pressure multi-phase separator comprises a tank body, a product inlet is arranged on the side wall of the tank body, and an inlet baffle is arranged inside the tank body close to the product inlet; a partition plate is fixedly arranged on the inner wall of the tank body below the product inlet, and a downcomer and a communication pipe are arranged on the partition plate; a liquid carbon dioxide outlet is arranged on the side wall of the tank body below the partition plate, and a weir plate is arranged inside the tank body close to the liquid carbon dioxide outlet; a gas outlet and a water outlet are fixedly arranged at the top and the bottom of the tank body respectively.

[0013] The water outlet at the bottom of the high-pressure multi-phase separator is directly or indirectly connected with the cold fluid inlet of the heat energy recovery heat exchanger, and the cold fluid outlet of the heat energy recovery heat exchanger is connected with the steam input pipeline of the high-pressure pipeline mixer.

[0014] The high-pressure pressure swing adsorption device is used for separating high-purity hydrogen and desorbed gas, and the gas inlet of the high-pressure pressure swing adsorption device is connected with the gas outlet at the top of the high-pressure multi-phase separator.

[0015] Further, the pore diameter of the micropore on the side wall of the metal sintered microporous tube is 0.5-5 microns.

[0016] Further, the oxygen distribution pipe is a stainless steel sintered mesh filter cartridge, and the filtering accuracy is 100-300 microns.

[0017] Further, the high-pressure multi-phase separator is provided with a mist catcher at the top.

[0018] Further, the bottom water outlet of the high-pressure multi-phase separator, the water storage tank and the first water supply pump are sequentially connected; the outlet of the first water supply pump is connected with the cold fluid inlet of the heat energy recovery heat exchanger.

[0019] Further, the bottom slag discharge pipe of the high-pressure gasification reactor is connected with the first solid collection tank, the inside of the first solid collection tank is arranged with a heating surface, the softening water storage tank, the second water supply pump and the inlet of the heating surface are sequentially connected, and the outlet of the heating surface is connected with the steam input pipe of the high-pressure pipeline mixer.

[0020] According to another aspect of the present application, a method for hydrogen production coupled with liquid carbon dioxide capture by gasification of carbonaceous substance is provided, which uses the system described above.

[0021] After the carbonaceous substance slurry is pressurized to 8-18 MPa, the slurry is input into the high-pressure gasification reactor through the raw material slurry feeding pipe; after the oxygen is pressurized to 8-18 MPa, the oxygen is input into the high-pressure gasification reactor through the oxygen distribution pipe; the mixture generated by the gasification reaction in the high-pressure gasification reactor penetrates the metal sintered microporous pipe to the annular gap between the metal sintered microporous pipe and the reaction shell, and then flows out of the high-pressure gasification reactor through the product discharge pipe at the lower part of the reaction shell into the heat energy recovery heat exchanger; in the heat energy recovery heat exchanger, the pressure and temperature of the mixture are reduced to a temperature lower than the critical temperature of carbon dioxide, and then the mixture is input into the high-pressure multi-phase separator.

[0022] The gas-liquid mixture is pre-separated into gas and liquid under the action of the inlet baffle of the high-pressure multi-phase separator, the pre-separated water and liquid carbon dioxide fall into the collection area through the downcomer, and the liquid carbon dioxide coalesces and floats to form a liquid carbon dioxide layer under the action of gravity, and the water droplets coalesce and settle to form a water layer; the liquid carbon dioxide at the upper layer overflows the weir and is discharged from the liquid carbon dioxide outlet into the liquid carbon dioxide storage tank.

[0023] The gas pre-separated in the high-pressure multi-phase separator is discharged through the gas outlet into the high-pressure pressure swing adsorption device to produce high-purity hydrogen and desorption gas.

[0024] Further, in the high-pressure multi-phase separator, the lower layer water in the collection area flows to the water storage tank from the bottom water outlet of the high-pressure multi-phase separator, enters the heat energy recovery heat exchanger from the cold fluid inlet through the first water supply pump, absorbs the heat of the gasification reaction product, is discharged from the cold fluid outlet of the heat energy recovery heat exchanger, and then enters the high-pressure gasification reactor after passing through the high-pressure pipeline mixer.

[0025] Further, the inorganic minerals and unreacted solid particles in the raw material are discharged from the slagging pipe at the bottom of the high-pressure gasification reactor into the first solid collection tank.

[0026] Further, the softened water is pressurized by the second feed water pump and enters the heated surface arranged in the first solid collection tank, absorbs the heat of the gasification residues, and then enters the high-pressure gasification reactor through the high-pressure pipe mixer.

[0027] The present application converts carbon-containing substances such as coal, biomass, and organic solid waste into high-pressure hydrogen-rich gas with a high hydrogen content by regulating the gasification of organic substances, carbon monoxide conversion, and low-carbon hydrocarbon steam reforming reactions in high-temperature and high-pressure water. The product gas is separated to obtain high-pressure pure hydrogen and liquid carbon dioxide. The separation of the high-pressure hydrogen-rich gas, liquid carbon dioxide, and water is realized based on the density difference in the high-pressure multiphase separator, and the liquid carbon dioxide is captured, effectively reducing the energy consumption of carbon dioxide separation. BRIEF DESCRIPTION OF DRAWINGS

[0028] Figure 1 is the process flow diagram of the carbon-containing substance gasification hydrogen production coupled with liquid carbon dioxide capture system described in the present application;

[0029] Figure 2 is a structural schematic diagram of the high-pressure gasification reactor described in the present application;

[0030] Figure 3 is a structural schematic diagram of the high-pressure pipe mixer described in the present application.

[0031] In the figure, 1 is a raw material slurry storage tank, 2 is a high-pressure pump, 3 is a liquid oxygen storage tank, 4 is a liquid oxygen vaporizer, 5 is an oxygen compressor, 6 is a softened water storage tank, 7 is a second feed water pump, 8 is a high-pressure gasification reactor, 9 is an oxygen distribution pipe, 10 is a raw material slurry feeding pipe, 11 is a reaction shell, 12 is a metal sintered microporous pipe, 13 is an insulation layer, 14 is a product discharge pipe, 15 is a slagging pipe, 16 is a first solid collection tank, 17 is a high-pressure pipe mixer, 18 is a heat recovery heat exchanger, 19 is a second solid collection tank, 20 is a first feed water pump, 21 is a high-pressure multiphase separator, 22 is a gas outlet, 23 is a mist catcher, 24 is an inlet baffle, 25 is a product inlet, 26 is a communication pipe, 27 is a downcomer, 28 is a liquid carbon dioxide outlet, 29 is a weir, 30 is a water outlet, 31 is a water storage tank, 32 is a carbon dioxide liquid storage tank, 33 is a high-pressure pressure swing adsorption device, 34 is a high-pressure hydrogen storage tank, 35 is a high-pressure methane-rich gas storage tank, 36 is a core pipe, 37 is an outer shell, 38 is a first inlet, and 39 is a second inlet. DETAILED DESCRIPTION

[0032] A typical embodiment of the present application provides a system for carbon-containing substance gasification hydrogen production coupled with liquid carbon dioxide capture, as shown in Figure 1As shown, the high-pressure gasification reactor 8, the high-pressure pipeline mixer 17, the heat energy recovery heat exchanger 18, the high-pressure multi-phase separator 21 and the high-pressure pressure swing adsorption device 33 are mainly included.

[0033] The high-pressure gasification reactor 8 includes a metal sintered microporous tube 12, a reaction shell 11 and a thermal insulation layer 13. The metal sintered microporous tube 12 is coaxially arranged inside the reaction shell 11, and an annular gap is formed between the outer wall of the metal sintered microporous tube 12 and the inner wall of the reaction shell 11. The thermal insulation layer 13 is wrapped outside the reaction shell 11.

[0034] The material of the reaction shell 11 is a seamless stainless steel tube. The material of the thermal insulation layer 13 is an aluminum silicate fiber felt.

[0035] The metal sintered microporous tube 12 is preferably a stainless steel sintered metal microporous tube. For example, 316L stainless steel powder is used as raw material, and a blank body with a specific shape is formed by rolling, isostatic pressing, extrusion, die pressing and other pressing forming methods. Then, the pressed blank is sintered in a protective atmosphere high-temperature furnace or a vacuum furnace to cause a series of physical and chemical processes such as diffusion, recrystallization and combination between particles, thereby forming a product containing a large number of interconnected or semi-interconnected pore structures inside. The pore diameter of the micropores on the side wall is 0.5-5 microns. As a filtering medium, the metal sintered microporous tube has good permeability, high strength, stable porosity and high filtering precision, and can efficiently remove suspended solids and particles in the gasification product. In this embodiment, the pore diameter of the micropores on the side wall of the metal sintered microporous tube 12 is 0.5-5 microns, which is used to remove inorganic minerals and unreacted solid particles in the gasification product by online filtration, without damaging the pressure-bearing surface of the high-pressure gasification reactor.

[0036] An end cover is arranged at the upper end surface of the reaction shell 11, and a raw material slurry feeding pipe 10 is fixed at the center of the end cover. The lower end of the raw material slurry feeding pipe 10 penetrates the end cover and extends to the upper part of the inner cavity of the metal sintered microporous tube 12. An oxygen distribution pipe 9 is arranged in the raw material slurry feeding pipe 10, and the lower end of the oxygen distribution pipe 9 extends to the middle part of the inner cavity of the metal sintered microporous tube 12. The oxygen distribution pipe 9 is connected with an oxygen input pipeline. An annular gap is formed between the outer wall of the oxygen distribution pipe 9 and the inner wall of the metal sintered microporous tube 12.

[0037] The oxygen distribution pipe 9 is a stainless steel sintered mesh filter cartridge, and the filtering precision is 100-300 microns. The oxidant is distributed in the high-pressure gasification reactor 8 through the oxygen distribution pipe 9, and the oxidant is uniformly distributed to avoid local hot spots.

[0038] More specifically, the equipment for inputting the oxidant into the high-pressure gasification reactor 8 includes a liquid oxygen storage tank 3, a liquid oxygen vaporizer 4 and an oxygen compressor 5 connected in sequence. The oxygen compressor 5 is connected to the high-pressure gasification reactor 8 through an oxygen input pipeline.

[0039] The lower part of the reaction shell 11 is provided with a product discharge pipe 14 which penetrates the heat insulation layer 13 and extends to the outside of the heat insulation layer 13.

[0040] The carbon-containing substance in the embodiment is coal, biomass, organic solid waste, etc. The carbon-containing substance slurry is pressurized to 8-18 MPa and then input into the high-pressure gasification reactor 8 through the raw material slurry feeding pipe 10. Oxygen is pressurized to 8-18 MPa and then input into the high-pressure gasification reactor 8 through the oxygen distribution pipe 9. The mixture generated by the gasification reaction in the high-pressure gasification reactor 8 penetrates the metal sintered microporous pipe 12 to the annular gap between the metal sintered microporous pipe 12 and the reaction shell 11, and then flows out of the high-pressure gasification reactor 8 from the product discharge pipe 14 at the lower part of the reaction shell 11 and enters the heat energy recovery heat exchanger 18. The water / carbon ratio in the reaction system of the present application is high, which is beneficial to the water gas shift reaction to proceed in the direction of generating hydrogen, and the volume fraction of hydrogen in the product gas is high.

[0041] The bottom of the metal sintered microporous pipe 12 is provided with a slag discharge pipe 15 which penetrates the reaction shell 11 and the heat insulation layer 13 from the inside to the outside and extends to the outside of the heat insulation layer 13. The inorganic minerals and unreacted solid particles in the raw material are discharged from the slag discharge pipe 15 at the bottom of the high-pressure gasification reactor 8.

[0042] In a preferred embodiment, the slag discharge pipe 15 at the bottom of the high-pressure gasification reactor 8 is connected to the first solid collection tank 16, the inside of which is provided with a heating surface, the softened water storage tank 6, the second feed water pump 7 and the inlet of the heating surface are connected in sequence, and the outlet of the heating surface is connected to the steam input pipe of the high-pressure pipe mixer 17. The rear end of the first solid collection tank 16 is connected to the second solid collection tank 19.

[0043] The inorganic minerals and unreacted solid particles discharged from the slag discharge pipe 15 at the bottom of the high-pressure gasification reactor 8 enter the first solid collection tank 16 and the second solid collection tank 19 in sequence. The softened water is pressurized by the second feed water pump 7, enters the heating surface arranged in the first solid collection tank 16, and then enters the high-pressure gasification reactor 8 through the high-pressure pipe mixer 17 after absorbing the heat of the gasification residues.

[0044] In the high-pressure pipe mixer 17, the carbon-containing substance slurry and the steam are mixed and heated, and then the mixture enters the high-pressure gasification reactor 8 through the raw material slurry feeding pipe 10. Figure 3 The high-pressure pipe mixer 17 is composed of a core pipe 36 and an outer shell 37. The core pipe 36 is trumpet-shaped and has many inclined holes in the wall. The middle part of the core pipe 36 is a mixing and heating zone, and the space between the core pipe 36 and the outer shell 37 is a steam zone. The first inlet 38 of the high-pressure pipe mixer 17 is connected to the carbon-containing substance slurry input pipe, the second inlet 39 is connected to the steam input pipe, and the outlet of the high-pressure pipe mixer is connected to the raw material slurry feeding pipe 10 of the high-pressure gasification reactor 8.

[0045] More specifically, the device for inputting raw material slurry includes a raw material slurry storage tank 1 and a high-pressure pump 2, the outlet end of the high-pressure pump 2 is connected to the first inlet 38 of the high-pressure pipeline mixer 17 through a carbon-containing substance slurry input pipeline, the water from the water storage tank 31 absorbs the heat of the gasification reaction product to become steam, enters the second inlet 39 of the high-pressure pipeline mixer 17, is sprayed into the mixing area at high speed through the core tube inclined hole, and the raw material slurry and the steam are fully mixed in the high-pressure pipeline mixer 17, and then the raw material slurry is input into the high-pressure gasification reactor 8 through the pipeline from the raw material slurry feeding pipe 10.

[0046] The heat energy recovery heat exchanger 18 includes a shell and a heat exchange pipe installed inside the shell; the two ends of the shell are respectively provided with a hot fluid inlet and a hot fluid outlet, and the two ends of the heat exchange pipe are respectively a cold fluid inlet and a cold fluid outlet.

[0047] The high-pressure gasification reactor product discharge pipe 14 is connected to the hot fluid inlet of the heat energy recovery heat exchanger 18, and the heat of the gasification product is recovered at medium pressure in the heat energy recovery heat exchanger 18.

[0048] The hot fluid outlet of the heat energy recovery heat exchanger 18 is connected to the product inlet of the high-pressure multi-phase separator 21. The mixture flowing out of the high-pressure gasification reactor 8 is reduced in temperature to a temperature lower than the critical temperature of carbon dioxide at medium pressure in the heat energy recovery heat exchanger 18, and then enters the high-pressure multi-phase separator 21.

[0049] The high-pressure multi-phase separator 21 includes a tank body, a product inlet 25 is arranged on the side wall of the tank body, and an inlet baffle 24 is arranged inside the tank body close to the product inlet 25; a partition plate is fixedly arranged on the inner wall of the tank body below the product inlet 25, a downcomer 27 and a communication pipe 26 are arranged on the partition plate; a liquid carbon dioxide outlet 28 is arranged on the side wall of the tank body below the partition plate, a weir plate 29 is arranged inside the tank body close to the liquid carbon dioxide outlet 28, and the liquid carbon dioxide outlet 28 of the high-pressure multi-phase separator is connected to the carbon dioxide liquid storage tank 32. The top and bottom of the tank body are respectively fixed with a gas outlet 22 and a water outlet 30.

[0050] As shown in Figure 1 The inlet baffle 24 and the weir plate 29 are both L-shaped baffles. The downcomer 27 is arranged vertically downward relative to the partition plate, and the communication pipe 26 is arranged vertically upward relative to the partition plate.

[0051] The gas-liquid mixture entering the high-pressure multi-phase separator is pre-separated into gas and liquid under the action of the inlet baffle 24, the pre-separated water and liquid carbon dioxide fall into the collection area through the downcomer 27, and the liquid carbon dioxide coalesces and floats to form a liquid carbon dioxide layer under the action of gravity settling, and the water droplets coalesce and settle to form a water layer. The liquid carbon dioxide on the upper layer overflows the weir plate 29 and is discharged from the liquid carbon dioxide outlet 28 into the carbon dioxide liquid storage tank 32.

[0052] Carbon dioxide exists in liquid state at high pressure and low temperature. The present embodiment uses the high pressure multi-phase separator described above to separate hydrogen-rich gas, liquid carbon dioxide and water according to their density differences and to capture liquid carbon dioxide, thereby effectively reducing the energy consumption for separating carbon dioxide.

[0053] In a preferred embodiment, the high pressure multi-phase separator 21 is provided with a mist eliminator 23 at the top thereof, and the pre-separated gas passes through the mist eliminator 23 to remove small liquid droplets.

[0054] The water outlet 30 at the bottom of the high pressure multi-phase separator 21 is directly or indirectly connected to the cold fluid inlet of the heat recovery heat exchanger 18, and the cold fluid outlet of the heat recovery heat exchanger 18 is connected to the steam input pipeline of the high pressure pipeline mixer 17.

[0055] Specifically, the water outlet 30 at the bottom of the high pressure multi-phase separator, the water storage tank 31 and the first feed water pump 20 are connected in sequence, and the outlet of the first feed water pump 20 is connected to the cold fluid inlet of the heat recovery heat exchanger.

[0056] In the high pressure multi-phase separator 21, the lower water in the liquid collection zone flows from the water outlet 30 at the bottom of the high pressure multi-phase separator to the water storage tank 31, enters the heat recovery heat exchanger 18 from the cold fluid inlet through the first feed water pump 20, absorbs the heat of the gasification reaction product, and is discharged from the cold fluid outlet of the heat recovery heat exchanger 18, and then enters the high pressure gasification reactor 8 through the high pressure pipeline mixer 17.

[0057] The gas inlet of the high pressure pressure swing adsorption device 33 is connected to the gas outlet 22 at the top of the high pressure multi-phase separator.

[0058] The pre-separated gas in the high pressure multi-phase separator 21 is discharged through the gas outlet 22 to the high pressure pressure swing adsorption device 33, and high-purity hydrogen gas and desorption gas are produced in the high pressure pressure swing adsorption device 33. The gas outlet of the high pressure pressure swing adsorption device 33 is connected to the high pressure hydrogen storage tank 34, and the desorption gas outlet of the high pressure pressure swing adsorption device 33 is connected to the high pressure methane-rich gas storage tank 35.

[0059] The high pressure pressure swing adsorption device 33 is used to purify hydrogen gas at high pressure. The adsorbent capacity is large, the processing capacity of the adsorption tower is high, high-pressure product hydrogen gas is obtained, and investment and energy consumption can be saved.

[0060] A relatively specific embodiment is provided below to make a relatively specific description of the technical solutions claimed in the present application.

[0061] In this embodiment, sawdust pulp with a mass fraction of 40% is pressurized to 16 MPa by a high-pressure pump 2, enters the high-pressure pipeline mixer 17, is mixed with superheated steam, and then enters the high-pressure gasification reactor 8. After the liquid oxygen is vaporized, it is pressurized to 16 MPa by the oxygen compressor 5 and enters the high-pressure gasification reactor 8 through the oxygen distribution pipe 9.

[0062] The gasification reaction produces a mixture of hydrogen / methane / low hydrocarbons / carbon monoxide / carbon dioxide / water at a temperature of 700°C / 16 MPa. The gasification product passes through the metal sintered microporous tube 12 into the annular gap between the metal sintered microporous tube 12 and the reaction shell 11, flows out of the reactor through the product discharge pipe 14 at the bottom of the reaction shell 11, and enters the heat recovery heat exchanger 18. During the entire process, the pressure of the fluid in the metal sintered microporous tube 12 is controlled to be 0.5 MPa higher than the pressure of the fluid in the annular gap.

[0063] The gasification product is isobarically cooled to 30°C in the heat recovery heat exchanger 18 and then enters the high-pressure multiphase separator 21 from the hot fluid outlet of the heat recovery heat exchanger 18. There, it interacts with the inlet baffle 24 of the high-pressure multiphase separator 21, pre-separating the gas and liquid. The pre-separated water and liquid CO2 fall through the downcomer 27 into the liquid collection area. Due to gravity settling, the liquid CO2 coalesces and floats to form a liquid CO2 layer, while the water droplets coalesce and settle to form a water layer. The upper layer of liquid CO2 overflows the weir plate 29 and is discharged from the liquid CO2 outlet 28 into the CO2 liquid storage tank 32. The lower layer of water flows from the bottom water outlet 30 of the high-pressure multiphase separator into the water storage tank 31. After passing through the first water feed pump 20 and entering the heat recovery heat exchanger 18 from the cold fluid inlet, it is reheated to a thermal state of 600°C / 16 MPa. It is then discharged from the cold fluid outlet of the heat recovery heat exchanger 18, passes through the high-pressure pipeline mixer 17, and enters the high-pressure gasification reactor 8, providing energy and gasifying agent for the gasification process.

[0064] The gas pre-separated in the high-pressure multiphase separator 21 passes through the mist collector 23 to remove smaller droplets, and is discharged to the high-pressure pressure swing adsorption device 33 under the control of the pressure control valve. The produced high-purity hydrogen enters the high-pressure hydrogen storage tank 34, and the desorbed gas enters the high-pressure methane-rich gas storage tank 35.

[0065] Inorganic minerals and unreacted solid particles in the feedstock are discharged from the bottom slag discharge pipe 15 of the high-pressure gasification reactor and sequentially enter the first solid collection tank 16 and the second solid collection tank 19 for collection and storage. Softened water enters the heating surface arranged in the first solid collection tank 16 and is heated to a thermal state of 600°C / 16 MPa. It then enters the high-pressure gasification reactor 8 through the high-pressure pipeline mixer 17, providing energy and gasifying agent for the gasification process.

Claims

1. A system for gasifying carbon-containing substances to produce hydrogen and capturing liquid carbon dioxide, characterized in that: include: - High-pressure gasification reactor, including metal sintered microporous tubes, reaction shell and insulation layer; The metal sintered microporous tube is coaxially arranged inside the reaction shell, and an annular gap is formed between the outer wall of the metal sintered microporous tube and the inner wall of the reaction shell; the insulation layer is wrapped around the outside of the reaction shell; An end cap is provided at the upper end surface of the reaction shell, and a raw material slurry feed pipe is fixed at the center of the end cap; the lower end of the raw material slurry feed pipe passes through the end cap and extends to the upper part of the inner cavity of the metal sintered microporous tube; an oxygen distribution pipe is provided in the raw material slurry feed pipe and the lower end of the oxygen distribution pipe extends to the middle part of the inner cavity of the metal sintered microporous tube, and the oxygen distribution pipe is connected to the oxygen input pipe; A product discharge pipe is provided at the lower part of the reaction shell, which passes through the insulation layer and extends to the outside of the insulation layer; a slag discharge pipe is provided at the bottom of the metal sintered microporous tube, which passes through the reaction shell and the insulation layer from the inside to the outside and extends to the outside of the insulation layer; — A high-pressure pipeline mixer, wherein the first inlet of the high-pressure pipeline mixer is connected to the carbonaceous material slurry input pipeline, and the second inlet is connected to the steam input pipeline; the outlet of the high-pressure pipeline mixer is connected to the raw material slurry feed pipe; --The heat recovery heat exchanger includes a shell and a heat exchange tube installed inside the shell; the shell is provided with a hot fluid inlet and a hot fluid outlet at both ends, and the heat exchange tube is provided with a cold fluid inlet and a cold fluid outlet at both ends; The product discharge pipe of the high-pressure gasification reactor is connected to the hot fluid inlet of the heat recovery heat exchanger, and the hot fluid outlet of the heat recovery heat exchanger is connected to the product inlet of the high-pressure multiphase separator; A high-pressure multiphase separator comprises a tank body, a product inlet being provided on the side wall of the tank body, an inlet baffle being provided near the product inlet inside the tank body; a partition being fixedly provided on the inner wall of the tank body below the product inlet, a downcomer and a connecting pipe being provided on the partition; a liquid carbon dioxide outlet being provided on the side wall of the tank body below the partition, a weir being provided near the liquid carbon dioxide outlet inside the tank body; and a gas outlet and a water outlet being fixedly provided at the top and bottom of the tank body, respectively. The water outlet at the bottom of the high-pressure multiphase separator is directly or indirectly connected to the cold fluid inlet of the heat recovery heat exchanger, and the cold fluid outlet of the heat recovery heat exchanger is connected to the steam input pipe of the high-pressure pipeline mixer; - A high-pressure pressure swing adsorption device is used to separate high-purity hydrogen and desorbed gas; the gas inlet of the high-pressure pressure swing adsorption device is connected to the gas production outlet at the top of the high-pressure multiphase separator.

2. The system according to claim 1, wherein: The diameter of the micropores on the side wall of the metal sintered microporous tube is 0.5 to 5 microns.

3. The system according to claim 1 or 2, characterized in that: The oxygen distribution pipe is a stainless steel sintered mesh filter cartridge with a filtration accuracy of 100 to 300 microns.

4. The system according to claim 3, wherein: A mist catcher is provided on the top of the high-pressure multi-phase separator.

5. The system according to claim 4, characterized in that: The bottom water outlet of the high-pressure multiphase separator, the water storage tank and the first water feed pump are connected in sequence; the outlet of the first water feed pump is connected to the cold fluid inlet of the heat energy recovery heat exchanger.

6. The system according to claim 5, characterized in that: The bottom slag discharge pipe of the high-pressure gasification reactor is connected to the first solid collection tank. A heating surface is arranged inside the first solid collection tank. The softened water storage tank, the second water feed pump and the inlet of the heating surface are connected in sequence. The outlet of the heating surface is connected to the steam input pipe of the high-pressure pipeline mixer.

7. A method for gasifying carbon-containing substances to produce hydrogen coupled with capturing liquid carbon dioxide, characterized by: Using the system as claimed in claim 6; After the carbonaceous material slurry is pressurized to 8-18 MPa, it is fed into the high-pressure gasification reactor through the raw material slurry feed pipe; after the oxygen is pressurized to 8-18 MPa, it enters the high-pressure gasification reactor through the oxygen distribution pipe; the mixture produced by the gasification reaction in the high-pressure gasification reactor passes through the metal sintered microporous tube body into the annular gap between the metal sintered microporous tube and the reaction shell, and flows out of the high-pressure gasification reactor through the product discharge pipe at the bottom of the reaction shell and enters the heat recovery heat exchanger; in the heat recovery heat exchanger, the temperature is reduced at a medium pressure to a temperature below the critical temperature of carbon dioxide, and then enters the high-pressure multiphase separator; The gas-liquid mixture is pre-separated by the baffle at the inlet of the high-pressure multiphase separator. The pre-separated water and liquid carbon dioxide fall into the liquid collection area through the downcomer. After gravity sedimentation, the liquid carbon dioxide coalesces and floats to form a liquid carbon dioxide layer, and the water droplets coalesce and settle to form a water layer. The liquid carbon dioxide in the upper layer overflows the weir plate and is discharged from the liquid carbon dioxide outlet and enters the carbon dioxide liquid storage tank. The gas pre-separated in the high-pressure multiphase separator is discharged through the gas production outlet to the high-pressure pressure swing adsorption device to produce high-purity hydrogen and desorbed gas.

8. The method according to claim 7, wherein: In the high-pressure multiphase separator, the lower layer of water in the liquid collection area flows from the bottom water outlet of the high-pressure multiphase separator to the water storage tank, passes through the first water feed pump and enters the heat recovery heat exchanger from the cold fluid inlet, absorbs the heat of the gasification reaction product, and is discharged from the cold fluid outlet of the heat recovery heat exchanger, and then passes through the high-pressure pipeline mixer into the high-pressure gasification reactor.

9. The method according to claim 7 or 8, characterized in that: The inorganic minerals and incompletely reacted solid particles in the raw materials are discharged from the slag discharge pipe at the bottom of the high-pressure gasification reactor and enter the first solid collection tank.

10. The method according to claim 9, characterized in that: The softened water is pressurized by the second water feed pump and enters the heating surface arranged in the first solid collection tank. After absorbing the heat of the gasified residue, it enters the high-pressure gasification reactor through the high-pressure pipeline mixer.

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