Hydrogen continuous preparation system based on biomass raw materials

Abstract

The utility model discloses a hydrogen continuous preparation system based on biomass raw materials, belongs to the technical field of hydrogen production, and can realize continuous preparation of hydrogen. A hydrogen continuous preparation system based on biomass raw materials comprises a raw material supply system, a supercritical water reactor, a primary fractionation device and a secondary fractionation device. A discharge port of the raw material supply system is connected with a feed port of the supercritical water reactor; temperature and pressure exceeding the critical value are provided in the supercritical water reactor; a gas outlet of the supercritical water reactor is connected with a gas inlet of the primary fractionation equipment, a gas outlet of the primary fractionation equipment is connected with a gas inlet of the secondary fractionation equipment, a gas outlet of the secondary fractionation equipment is connected with the hydrogen storage device through a pressure regulating valve, and a liquid outlet of the secondary fractionation equipment is connected with the carbon dioxide storage device through a pressure regulating valve; a water inlet is formed in the lower part of the supercritical water reactor, a gas outlet is formed in the top of the supercritical water reactor, the supercritical water reactor comprises a plurality of temperature zones, and each temperature zone is provided with a heating device and a cooling device.

Description

TECHNICAL FIELD

[0001] The utility model relates to hydrogen production technical field, concretely relates to a hydrogen continuous preparation system based on biomass raw material. BACKGROUND

[0002] Hydrogen as energy, only generates water in air combustion, has no pollution to the environment. According to the source of hydrogen, it is divided into gray hydrogen, blue hydrogen and green hydrogen.

[0003] At present, there are many methods to manufacture hydrogen, such as: (1) a large amount of hydrogen is made by natural fossil fuel pyrolysis gray hydrogen, and toxic and harmful substances such as gas pollutants, tar are generated in the process;(2) hydrogen is prepared by biogas fermentation;(3) hydrogen is prepared by high temperature and catalyst;(4) hydrogen is prepared by high cost electrolysis of water.

[0004] The above-mentioned several methods for preparing hydrogen have the problems of low utilization rate of raw materials, complex composition of output material, low selectivity, long reaction period and high cost. Utilizing biomass to prepare hydrogen is one of the research directions at present, biomass refers to the total name of various organic matters formed by direct or indirect utilization of photosynthesis, has the advantages of renewable, abundant reserves, low pollution and storability, is the fourth largest energy after coal, oil and natural gas. In the supercritical water environment of high temperature and high pressure, biomass is continuously converted into hydrogen and other gases through thermochemical reaction (including hydrolysis, cracking, oxidation and reduction) process. Because the reaction condition breaks through the critical point of water (374 DEG C, 22.1MPa), water shows unique physical and chemical properties, so that biomass can be efficiently decomposed and hydrogen is generated.

[0005] At present, there are also some supercritical water hydrogen production systems, such as the supercritical water hydrogen production device disclosed in Chinese patent document 202122836859.4. The device is the same as most existing hydrogen production systems, which first passes through a supercritical boiler to make the liquid reach a supercritical state and then enters the next process procedure. In this way, the boiler needs to heat the liquid to a supercritical state (high temperature and high pressure), which needs a long time and is difficult to maintain continuous and stable output. After processing a certain amount each time, it needs to be stopped and refilled, which causes the process to be interrupted. UTILITY MODEL CONTENTS

[0006] The utility model aims at providing a hydrogen continuous preparation system based on biomass raw material, biomass is continuously thermochemically reacted in water, a mixture of hydrogen, water and carbon dioxide is obtained, and hydrogen is finally obtained by fractional distillation and separation, and the production continuity is better

[0007] In order to realize the above-mentioned purpose, the technical scheme adopted by the utility model is as follows:

[0008] A continuous hydrogen production system based on biomass raw material, comprising a raw material supply system, a supercritical water reactor, a primary fractionation device, and a secondary fractionation device;

[0009] The discharge port of the raw material supply system is connected to the feed port of the supercritical water reactor; the supercritical water reactor is provided with temperature and pressure exceeding the critical point; the gas outlet of the supercritical water reactor is connected to the gas inlet of the primary fractionation device, the gas outlet of the primary fractionation device is connected to the gas inlet of the secondary fractionation device, the gas outlet of the secondary fractionation device is connected to the hydrogen storage device through a pressure regulating valve, and the liquid outlet of the secondary fractionation device is connected to the carbon dioxide storage device through a pressure regulating valve.

[0010] The supercritical water reactor is provided with a water inlet at the lower part and a gas outlet at the top, and comprises a plurality of temperature zones, each of which is provided with a heating device and a cooling device.

[0011] The supercritical water reactor is provided with a safety valve.

[0012] As a preferred technical solution, the liquid outlet of the primary fractionation device is connected to the water inlet of the raw material supply system and / or the supercritical water reactor through a pump pipeline.

[0013] As a preferred technical solution, a high-pressure pump is arranged on the pipeline connecting the raw material supply system and the supercritical water reactor.

[0014] As a preferred technical solution, a fuel injector is arranged on the pipeline connecting the raw material supply system and the supercritical water reactor.

[0015] As a preferred technical solution, the pipeline connecting the raw material supply system and the supercritical water reactor is communicated through a preheating device.

[0016] As a preferred technical solution, the supercritical water reactor is provided with a fixed catalyst bed.

[0017] As a preferred technical solution, the supercritical water reactor comprises a plurality of reactors connected in series, each reactor is provided with a gas outlet at the top and a gas inlet at the lower part, the gas flows from bottom to top in each reactor, the gas outlet of the upper-stage reactor is communicated with the gas inlet of the lower-stage reactor, and each reactor is provided with a heating device and a cooling device, wherein the temperature of the first-stage reactor is the lowest and the temperature of the last-stage reactor is the highest.

[0018] As a preferred technical solution, each reactor is provided with a fixed catalyst bed.

[0019] As a preferred technical solution, the bottom of the supercritical water reactor is provided with a slag discharge port, and the slag discharge port is provided with a slag discharge valve, which can be two and connected in series through a pipeline.

[0020] As a preferred technical scheme, an exhaust valve is arranged on the pipeline between the pressure regulating valve and the hydrogen storage device gas inlet end; an exhaust valve is also arranged on the pipeline between the pressure regulating valve and the liquid carbon dioxide storage device liquid inlet end.

[0021] As a preferred technical scheme, the supercritical water reactor is internally provided with a temperature sensor and a pressure sensor.

[0022] As a preferred technical scheme, the first-stage reactor is provided with a water inlet at the lower part.

[0023] As a preferred technical scheme, the primary fractionation equipment and the secondary fractionation equipment are both chemical equipment for separating liquid and gas through cooling.

[0024] Compared with the prior art, the utility model has the following beneficial effects:

[0025] In the embodiment of the utility model, the biomass slurry is gradually preheated to a supercritical state through the preheating device and the reactor, and the cooperation of the safety valve and the pressure regulating valve in pressure regulation can realize continuous hydrogen production.

[0026] In the embodiment of the utility model, multiple temperature steps are arranged in the supercritical reactor, so that the biomass reaction is more complete, and stable hydrogen production is realized. BRIEF DESCRIPTION OF DRAWINGS

[0027] In order to more clearly illustrate the technical scheme of the embodiment of the utility model, the drawings of the embodiment will be briefly introduced below.

[0028] Fig. 1 In the embodiment, a process system diagram of a multi-stage supercritical water reactor is adopted.

[0029] Fig. 2 In the embodiment, a process system diagram of a series supercritical water reactor is adopted.

[0030] Fig. 3 In the embodiment, a structural schematic diagram of the multi-stage supercritical water reactor is adopted.

[0031] Among them, the sign of the drawing is as follows:

[0032] 1 - feed container, 2 - metering valve, 3 - preheating device, 4 - high-pressure pump, 5 - fuel injector, 6 - fixed bed of catalyst, 7 - slag valve, 8 - safety valve, 9 - high-temperature gas filtration system, 10 - primary fractionation device, 11 - secondary fractionation device, 12 - pressure regulating valve, 13 - exhaust valve, 14 - hydrogen storage device, 15 - carbon dioxide storage device, 16 - multi-stage supercritical water reactor, 17 - series ultra-supercritical water reactor, 161 - electric heating element, 162 - coolant channel, 163 - water inlet of the reactor, 164 - slag outlet, 165 - gas outlet of the reactor. DETAILED DESCRIPTION

[0033] The specific embodiments of the present application will be further described in detail below with reference to the accompanying drawings and examples. The following examples are used to illustrate the present application, but not to limit the scope of the present application.

[0034] In the description of the present application, it should be understood that the terms "upper", "lower", "left", "right", "front", "back", "top", "bottom" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore should not be understood as limiting the present application. It should be understood that the terms "first", "second" and the like are used to describe various information in the present application, but these information should not be limited to these terms, and these terms are only used to distinguish the same type of information from each other. For example, "first" information can also be referred to as "second" information, and similarly, "second" information can also be referred to as "first" information without departing from the scope of the present application.

[0035] The present application provides a hydrogen continuous preparation system based on biomass raw materials to prepare hydrogen. The biomass slurry is added into a supercritical water reactor for thermal chemical reaction. The supercritical water reactor is controlled in stages for temperature control to obtain a mixture of hydrogen, water and carbon dioxide. The mixture is separated into water by primary fractionation, and separated into liquid carbon dioxide and hydrogen by secondary fractionation, so as to prepare hydrogen.

[0036] The technical solution in the present application is to realize the preparation of hydrogen, and the general idea is as follows:

[0037] The supercritical water reactor is provided with a segmented heating area, so that the biomass slurry is heated in stages, and the temperature is controlled to produce a mixture of hydrogen, water and carbon dioxide. The mixture enters the next stage of fractionation process through the gas outlet at the top of the supercritical water reactor.

[0038] As Figs. 1-3As shown in the embodiment, the system includes a raw material supply system, a supercritical water reactor, a primary fractionation device 10, and a secondary fractionation device 11.

[0039] The raw material supply system is connected to the supercritical water reactor at the inlet of the reactor. The raw material supply system supplies biomass slurry, which is obtained by grinding biomass with water. The biomass slurry is pumped into the supercritical water reactor by a high-pressure pump 4. The supercritical water reactor provides a temperature and pressure above the critical point, so that the biomass is in a "combustion" state in water, and a thermo-chemical reaction is carried out. Then, a mixture of water, carbon dioxide, and hydrogen is discharged from the supercritical water reactor through a gas outlet 165 at the top of the reactor.

[0040] The gas outlet of the supercritical water reactor is connected to the gas inlet of the primary fractionation device 10 through a pipeline. The gas outlet of the primary fractionation device 10 is connected to the gas inlet of the secondary fractionation device 11 through a pipeline. The gas outlet of the secondary fractionation device 11 is connected to a hydrogen storage device through a pressure regulating valve 12. The water outlet of the secondary fractionation device 11 is connected to a liquid carbon dioxide storage device 15 through a pressure regulating valve 12. The water outlet of the primary fractionation device 10 is connected to the raw material supply system and / or the supercritical water reactor through a pipeline, and is recycled.

[0041] A water inlet is arranged at the lower part of the supercritical water reactor. The water inlet 163 of the reactor is provided with a water inlet valve. The water inlet is connected to the water outlet of the primary fractionation device 10 and an external water source through a pipeline with a pump. Before the system is started, water is pumped into the reactor to a height of 30% of the volume of the reactor to stop water injection as an initial water level. The gas inlet of the supercritical water reactor is below the water level. The injected slurry is "combusted" (thermo-chemical reaction) in the supercritical water to generate a mixture of hydrogen, water, and carbon dioxide.

[0042] In some possible embodiments, the raw material supply system includes a feeding container 1, which contains biomass slurry obtained by grinding biomass with water in a certain proportion. A metering valve 2 is arranged at the outlet of the feeding container 1 to accurately discharge the biomass slurry. The outlet of the feeding container 1 is connected to the inlet of a high-pressure pump 4. The outlet of the high-pressure pump 4 is connected to the inlet of a fuel injector 5. The outlet of the fuel injector 5 is connected to the inlet of the supercritical water reactor. The biomass slurry is injected into the supercritical water reactor by the high-pressure pump 4 and the fuel injector 5. The structure of the fuel injector is not limited in the embodiment, as long as it can realize the function of carrying out injection of the critical liquid. Some possible options are given in the embodiment, such as a Spray Inc. injector and a HYB-GZ injector.

[0043] Further, the raw material supply system can be connected to the supercritical water reactor through a preheating device 3, which can be a tube-shell preheater, an electric heating preheating device, etc. There are various existing chemical equipment capable of realizing preheating of the pre-mixed liquid, and the present embodiment is not specifically limited. The preheating device 3 is connected to the outlet of the raw material supply system, and the outlet of the preheating device 3 is connected to the inlet of the high-pressure pump 4 through a pipeline.

[0044] In some possible embodiments, an exhaust valve 13 is arranged on the pipeline between the pressure regulating valve 12 and the hydrogen storage device inlet, and an exhaust valve 13 is also arranged on the pipeline between the pressure regulating valve 12 and the liquid carbon dioxide storage device 15 inlet. The exhaust valve 13 is used to exhaust unqualified gas in the pipeline before production.

[0045] In some possible embodiments, the fractionation equipment can be a fractionation tower. In the present embodiment, the fractionation equipment is a commonly used equipment in the chemical field, and the present embodiment is not specifically limited. The fractionation equipment separates the single gas after liquefaction by cooling to reduce the temperature of the gas.

[0046] In some possible embodiments, the supercritical water reactor is a series supercritical water reactor, that is, it includes a plurality of reactors in series, each reactor is provided with a gas outlet at the top and a gas inlet at the bottom, and the gas flows from bottom to top in each reactor. The gas outlet of the upper reactor is in communication with the gas inlet of the lower reactor. Each reactor is provided with a heating device for raising the temperature of the reactor to a corresponding temperature. Specifically, the temperature gradient between the reactors is 374-1000°C. The temperature of the first reactor is the lowest, and the temperature of the last reactor is the highest. Each reactor is provided with a cooling device, which cooperates with the heating device to control the temperature in the reactor to the required temperature. The reactor is provided with a sensor for collecting temperature and feeding back to the controller, and the controller controls the operation of the heating device and the cooling device to control the temperature in the reactor to the required temperature. At this time, only the first reactor is provided with a water inlet for pumping water.

[0047] Specifically, in the present embodiment, the heating device is an electric heating element 161, which is uniformly wound on the outer wall of the cylinder of the reactor. Of course, the electric heating element 161 is not exposed, and an insulating layer of ceramic fiber or mica is covered outside the electric heating element. And the reactor and the electric heating element are further provided with a protective cover, and the protective cover is provided with heat insulation material. This is one of the basic design schemes of the heating type reactor in the chemical field, and the present embodiment will not be described again. The electric heating element 161 is connected to a power source. The electric heating element is preferably an electric heating wire made of platinum rhodium material or molybdenum material.

[0048] Specifically, in the embodiment, the cooling device comprises a coolant channel 162 and a coolant circulation machine. In the embodiment, the coolant channel is a reactor interlayer, and the interlayer is provided with an inlet and an outlet, and the inlet and the outlet are connected with the coolant circulation machine through pipelines. The coolant circulation machine is an existing device, and there are various types on the market, and the embodiment does not make specific limitations. In addition, the coolant channel can also be a cooling coil arranged in the reactor, and the inlet and the outlet of the cooling coil are connected with the coolant circulation machine through pipelines.

[0049] In other embodiments, the supercritical water reactor is a single multi-stage supercritical water reactor 16, that is, a plurality of heating zones are arranged in the reactor from top to bottom, and each heating zone is provided with a heating element, and the heating element makes the temperature of each heating zone different, thereby realizing segmented heating. Specifically, the reactor is provided with a feeding port at the lower part of the side wall, the feeding port is communicated with the outlet of the fuel injector 5, the reactor is provided with a gas outlet at the top, and the reactor is provided with a funnel-shaped slag discharge port 164 at the bottom, and the slag discharge port 164 is provided with a slag discharge valve 7.

[0050] As a preferred mode, the slag discharge valve 7 can be two, which are connected in series through pipelines. When discharging slag, the slag discharge valve 7 far away from the slag discharge port is closed first, then the slag discharge valve 7 close to the slag discharge port is opened. After the slag enters the pipeline between the two valves, the valve close to the slag discharge port is closed, and the valve far away from the slag discharge port is opened, so that the slag is discharged from the pipeline between the two valves.

[0051] In some feasible embodiments, a pressure sensor is arranged in the reactor, and the pressure sensor collects data for the controller. Two safety valves 8 are arranged at the top of the reactor, and the threshold value of the safety valve 8 is set to be 5-10% higher than the highest pressure of the reaction and 50-20% lower than the pressure resistance value of the reactor and pipelines.

[0052] It should be noted that the pressure control in the reactor is realized by adjusting the temperature rise in the reactor to increase the pressure, and by increasing the opening of the pressure regulating valve 12 to decrease the pressure.

[0053] In other feasible embodiments, a catalyst fixed bed 6 is further arranged in the reactor for reaction catalysis. The catalyst fixed bed 6 is an existing structure, which is generally in a honeycomb structure and is fixed in the reactor through a mounting frame. The catalyst fixed bed 6 is provided with at least one.

[0054] As a preferred mode, each temperature step corresponds to a reactor provided with a catalyst fixed bed 6. In the embodiment, the selection of the catalyst in the catalyst fixed bed 6 is not limited, because there are various sources of biomass, including at least one or more of the mixture of straw, wood, firewood, leaves, sawdust, bamboo, paper renewable materials and household garbage, industrial plastic garbage and domestic sewage sludge. The selection of the catalyst of the catalyst fixed bed 6 needs to be determined according to the biomass itself.

[0055] In some possible embodiments, the gas outlet of the supercritical water reactor is connected to the gas inlet of the high-temperature gas filtration system 9, and the gas outlet of the high-temperature gas filtration system 9 is connected to the gas inlet of the primary fractionation device 10, so as to filter out solid particles of incomplete thermalization reaction. The high-temperature gas filtration system 9 is an existing device, and the model reference given in the embodiment is not used to limit the specific structure of the high-temperature gas filtration system 9. The high-temperature gas filtration system 9 can be of the XKP-IS model, the XKP-TIS model, etc.

[0056] In the description of the present application, it should be pointed out that, unless otherwise explicitly specified and limited, the terms "connected", "connected" should be understood broadly, for example, it can be fixedly connected, or it can be detachably connected, or integrally connected; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium, or it can be connected inside two elements. For ordinary skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0057] The above is only the preferred embodiment of the present application, and it should be pointed out that for ordinary skilled in the art, without departing from the technical principles of the present application, a number of improvements and substitutions can be made, and these improvements and substitutions should also be considered as the protection scope of the present application.

Claims

1. A continuous hydrogen production system based on a biomass feedstock, characterized in that, The system comprises a raw material supply system, a supercritical water reactor, a primary fractionation device and a secondary fractionation device. The raw material supply system is connected to the supercritical water reactor through a pipe. The supercritical water reactor is provided with a temperature and pressure exceeding the critical point. The supercritical water reactor is connected to the primary fractionation device through a pipe.

2. The continuous hydrogen production system based on biomass feedstock according to claim 1, wherein, The primary fractionation device is connected to the secondary fractionation device through a pipe.

3. The continuous hydrogen production system based on biomass feedstock according to claim 1, wherein, The supercritical water reactor is provided with a safety valve.

4. The continuous hydrogen production system based on biomass feedstock according to claim 1, wherein, The primary fractionation device is connected to the raw material supply system and / or the supercritical water reactor through a pipe.

5. The continuous hydrogen production system based on biomass feedstock according to claim 1, wherein, The pipe connecting the raw material supply system and the supercritical water reactor is provided with a high-pressure pump.

6. The continuous hydrogen production system based on biomass feedstock according to claim 1, wherein, The pipe connecting the raw material supply system and the supercritical water reactor is provided with a fuel injector.

7. The continuous hydrogen production system based on biomass feedstock according to claim 1, wherein, The raw material supply system is connected to the supercritical water reactor through a preheating device.

8. The continuous hydrogen production system based on biomass feedstock according to claim 7, wherein, The supercritical water reactor is provided with a fixed catalyst bed.

9. The continuous hydrogen production system based on biomass feedstock according to claim 1, wherein, The supercritical water reactor comprises several reactors connected in series.

10. The continuous hydrogen production system based on biomass feedstock according to claim 1, wherein, Each reactor is provided with a gas outlet at the top and a gas inlet at the bottom.

11. The continuous hydrogen production system based on biomass feedstock according to claim 1, wherein, The gas flows from bottom to top in each reactor.

12. The continuous hydrogen production system based on biomass feedstock according to claim 7, wherein, The gas outlet of the first reactor is connected to the gas inlet of the second reactor.

13. The continuous hydrogen production system based on biomass feedstock according to claim 1, wherein, Each reactor is provided with a heating device and a cooling device. The first reactor has the lowest temperature and the last reactor has the highest temperature. Each reactor is provided with a fixed catalyst bed. The supercritical water reactor is provided with a slag outlet. The slag outlet is provided with a slag valve. The pipe connecting the pressure regulating valve and the hydrogen storage device is provided with an exhaust valve. The pipe connecting the pressure regulating valve and the liquid carbon dioxide storage device is also provided with an exhaust valve. The supercritical water reactor is provided with a temperature sensor and a pressure sensor. The first reactor is provided with a water inlet at the bottom. The primary fractionation device and the secondary fractionation device are chemical devices for separating liquid and gas through cooling.

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