Vehicle biological methanol reforming hydrogen production reaction system and methanol reforming hydrogen production process

Abstract

The invention belongs to the technical field of biological raw material reforming hydrogen production, and particularly relates to a vehicle biological methanol reforming hydrogen production reaction system and a methanol reforming hydrogen production process. The vehicle biological methanol reforming hydrogen production reaction system comprises a liquid inlet flow meter, a biological methanol solution tank, a micro-channel hydrogen production reactor, an air cooling device, a condensation drying device, a CO catalytic conversion device, a CO2 absorption device, a biological methanol storage tank, a water storage tank and a temperature control device which are sequentially communicated through pipelines. The structure of the reforming hydrogen production reactor and hydrogen production process parameters are improved, the methanol steam reforming hydrogen production reactor is used for converting biological methanol into mixed gas mainly containing hydrogen, and the separated hydrogen serves as clean energy to be applied to agricultural vehicles. The methanol reforming hydrogen production process provided by the invention is a novel environment-friendly hydrogen production process, and has better popularization and application prospects.

Description

Technical Field

[0001] The present invention belongs to the technical field of hydrogen production by reforming biological raw materials, and in particular relates to a vehicle-use biological methanol reforming hydrogen production reaction system and a methanol reforming hydrogen production process. Background Art

[0002] Hydrogen energy has attracted people's attention due to its advantages such as high energy density, clean and pollution-free, high efficiency, renewable, and abundant reserves. There are many methods for preparing hydrogen, including chemical hydrogen production and biological hydrogen production. Among them, chemical hydrogen production is the most mature and large-scale stable hydrogen production method. Among the many compounds, methanol has become the preferred raw material for chemical in-situ hydrogen production because of its high hydrogen-to-carbon ratio, renewable nature, wide source of raw materials, multi-method preparation, and easy transportation at room temperature and pressure.

[0003] Biomethanol has the same chemical formula as methanol, but there are some differences in the production methods. Biomethanol is synthesized by catalytic conversion of biohydrogen and carbon dioxide under certain temperature and pressure conditions.

[0004] Methanol reforming hydrogen production technology is considered to be one of the best ways to produce hydrogen due to its simple equipment, strong convenience, fast hydrogen production speed, high hydrogen content, and few by-products. Methanol reforming hydrogen production mainly refers to the process of catalytically reforming methanol into a mixed gas mainly composed of hydrogen under certain temperature, pressure and other conditions under the action of a catalyst. There are mainly methanol steam reforming hydrogen production, methanol partial oxidation reforming hydrogen production and methanol autothermal reforming hydrogen production.

[0005] Methanol steam reforming hydrogen production refers to the process in which methanol and water are first gasified and then generate hydrogen, carbon dioxide and a small amount of carbon monoxide under the action of a catalyst under certain temperature and pressure conditions. The efficiency of methanol steam reforming hydrogen production mainly depends on the heat exchange performance of the reactor. The better the heat transfer performance, the higher the reforming efficiency. Therefore, the design and selection of the reactor structure is the basis for reforming hydrogen production. In addition, in the process of methanol steam reforming hydrogen production, the catalyst can promote the rapid progress of the reforming reaction and improve the hydrogen yield, selectivity and stability. There are many types of reactors currently available, which can be mainly divided into tubular reactors and plate reactors; according to the internal structure of the reactor, it can be divided into microchannel reactors, membrane reactors, capillary microreactors, etc.

[0006] In the field of transportation, hydrogen energy is also widely used. As early as the 1980s, someone proposed a methanol reforming hydrogen production device for vehicles. This device uses the waste heat of vehicle engine exhaust as a heat source, and provides heat to the methanol reforming hydrogen production reactor through a heat exchanger. The H produced by methanol reforming 2 ,CO,CO 2 etc. are directly introduced into the engine for combustion to provide kinetic energy for the vehicle. However, there are few reports on the application of hydrogen energy in agricultural machinery.

[0007] Based on the power requirements of agricultural vehicles, the inventors designed a vehicle-mounted agricultural vehicle biomethanol steam reforming hydrogen production device. The core part of the device is a methanol steam reforming hydrogen production reactor, which includes a methanol-water solution gasification superheating area and a catalytic reforming area. No additional gasification device is required, thus realizing the portability of methanol reforming hydrogen production.

[0008] At the same time, the inventors improved the structure of the methanol steam reforming hydrogen production reactor, adjusted the catalytic reforming area inside the reactor to four layers, increased the surface area of ​​the catalytic reforming area, and slightly adjusted the width and depth of the reactor to avoid increasing the external surface area of ​​the reactor as much as possible and improve the hydrogen production efficiency.

[0009] According to the previous process optimization parameters, the H 2 Content, CO content, CO 2 The content, specific hydrogen production, hydrogen production rate and biomethanol conversion rate were investigated, and the effects of catalyst bed distribution ratio, feed rate, reforming temperature and water-alcohol molar ratio of biomethanol solution on reforming hydrogen production were studied. Summary of the invention

[0010] The present invention provides a vehicle-use biomethanol reforming hydrogen production reaction system and a methanol reforming hydrogen production process. By improving the structure of the reforming hydrogen production reactor and the hydrogen production process parameters, a methanol steam reforming hydrogen production reactor is used to realize the conversion of biomethanol into a mixed gas mainly composed of hydrogen, and the separated hydrogen is used as a clean energy for the power supply of agricultural vehicles.

[0011] Based on the above purpose, the present invention adopts the following technical solutions:

[0012] A vehicle-use biomethanol reforming hydrogen production reaction system comprises a liquid inlet flow meter, a biomethanol solution tank, a microchannel hydrogen production reactor, an air cooling device, a condensation drying device, a CO catalytic conversion device, a CO 2 absorption unit, as well as biomethanol storage tanks, water storage tanks and temperature control equipment;

[0013] The liquid inlet flow meter is provided with a first inlet end, a second inlet end and a first outlet end; the liquid inlet flow meter can control the flow rate of the material entering the microchannel hydrogen production reactor;

[0014] The outlet end of the biomethanol storage tank and the outlet end of the water storage tank are respectively connected to the first inlet end and the second inlet end of the liquid inlet flow meter through pipelines;

[0015] The pipeline connecting the biomethanol solution tank and the microchannel hydrogen production reactor is the reactor feed pipe;

[0016] The pipeline connecting the microchannel hydrogen production reactor and the air cooling device is the reactor discharge pipe;

[0017] The microchannel hydrogen production reactor is a rectangular parallelepiped structure, including a reactor body and a reactor cover. The reactor body is surrounded by a bottom plate and four side wall plates arranged on the top of the bottom plate. A reaction chamber is formed in the middle surrounded by the bottom plate and the four side wall plates. A plurality of partition plates are arranged in sequence from top to bottom.

[0018] The reactor cover is arranged on the top of the reactor body, and the reactor cover is detachably connected to the reactor body.

[0019] Furthermore, the vehicle biomethanol reforming hydrogen production reaction system also includes a gas online detector and a gas meter; the feed end of the gas online detector is connected to the CO 2 The discharge end of the absorption device is connected, and the discharge end of the gas online detector is connected with the feed end of the gas meter through a pipeline.

[0020] Furthermore, a liquid mixer is provided on the pipeline connecting the liquid inlet flow meter and the biomethanol solution tank, which can improve the mixing degree of the liquid material flowing out of the liquid inlet flow meter.

[0021] Furthermore, a liquid pump flow meter and a pressure pump are also provided on the pipeline connecting the biomethanol solution tank and the microchannel hydrogen production reactor.

[0022] Furthermore, a liquid level sensor is also provided on the side wall of the biomethanol solution tank, the liquid level sensor is provided with a signal output end, and the liquid inlet flow meter is provided with a signal input end. The signal output end of the liquid level sensor is electrically connected to the signal input end of the liquid inlet flow meter through a line, and the liquid level of the liquid material in the biomethanol solution tank is detected by the liquid level sensor. When the liquid level is lower than the set value, the liquid level sensor sends an open signal to the liquid inlet flow meter, and the liquid material in the liquid inlet flow meter is discharged from the first outlet end; when the liquid level in the biomethanol solution tank is lower than the set value, the liquid level sensor sends a close signal to the liquid inlet flow meter, and the liquid inlet flow meter stops discharging the liquid material; specifically, the connection between the signal output end of the liquid level sensor and the signal input end of the liquid inlet flow meter in the present application adopts the conventional setting in the prior art, and is not the inventive point of the present invention, so it will not be repeated.

[0023] Furthermore, the liquid level sensor is a XKCY26 type patch type liquid sensor.

[0024] Furthermore, the liquid inlet flow meter is also provided with a reflux end; the outlet end of the condensation and drying device is also provided with a bypass pipe, which is connected to the reflux end of the liquid inlet flow meter.

[0025] Furthermore, a first valve is provided on the discharge pipe of the reactor; a second valve is provided on the pipeline connecting the air cooling device and the condensation and drying device; and a third valve is provided on the bypass pipe.

[0026] Furthermore, the liquid inlet flow meter also has a reverse reflux function, which can return the incompletely reacted biomethanol and incompletely reacted water collected at the reflux end to the biomethanol storage tank or the water storage tank through a pipeline.

[0027] Furthermore, a sealing groove structure is formed between the bottom plate of the reactor body and the four side wall plates at the front, rear, left and right sides.

[0028] Further preferably, the partition plate is provided with three layers, and the internal space between the reactor body and the reactor cover is divided into four layers from top to bottom by the three layers of partition plates provided in the reactor body, namely, a catalytic reforming space is formed between the bottom plate of the reactor body and the partition plate, between the reactor cover and the partition plate, and between two adjacent layers of partition plates above and below.

[0029] Furthermore, the three-layer partition plate has the same front-to-back width and different left-to-right lengths.

[0030] Furthermore, the catalytic reforming space on the upper surface of the bottom plate of the reactor body is divided into a gasification area, an overheating area, and a catalytic reforming area from left to right.

[0031] Further preferably, the gasification region on the upper surface of the bottom plate of the reactor body is provided with a plurality of gasification region heat conduction rows, each of which includes a plurality of gasification region heat conduction ridges extending from left to right; specifically, the gasification region heat conduction rows on the upper surface of the bottom plate of the reactor body are provided with left and right rows, and each gasification region heat conduction ridge in the left gasification region heat conduction row and each gasification region heat conduction ridge in the right gasification region heat conduction row are arranged alternately;

[0032] The catalytic reforming region on the upper surface of the bottom plate of the reactor body is provided with several rows of catalytic reforming region heat-conducting rows, and each catalytic reforming region heat-conducting row includes several catalytic reforming region heat-conducting ridges extending from left to right; specifically, the catalytic reforming region heat-conducting rows on the upper surface of the bottom plate of the reactor body are provided with two rows on the left; each catalytic reforming region heat-conducting ridge in the left catalytic reforming region heat-conducting row and each catalytic reforming region heat-conducting ridge in the right catalytic reforming region heat-conducting row are arranged alternately.

[0033] Furthermore, each gasification region heat conduction ridge in the left gasification region heat conduction row and each gasification region heat conduction ridge in the right gasification region heat conduction row are strip structures that rise sequentially from left to right.

[0034] Furthermore, the highest point on the right end of each heat-conducting ridge of the gasification region in the left heat-conducting row of the gasification region and the highest point on the right end of each heat-conducting ridge of the gasification region in the right heat-conducting row of the gasification region are slightly higher than or the same as the height of the heat-conducting ridge of the catalytic reforming region.

[0035] Furthermore, the three layers of partition plates are all located above the catalytic reforming area on the upper surface of the bottom plate of the reactor body.

[0036] Furthermore, the left and right length of the bottom partition plate is slightly smaller than the length of the catalytic reforming area on the upper surface of the bottom plate of the reactor body, the left and right length of the middle partition plate is slightly larger than the left and right length of the bottom partition plate, and the left and right length of the top partition plate is slightly larger than the left and right length of the middle partition plate.

[0037] Furthermore, two rows of catalytic reforming region heat conduction rows are provided on the upper surface of the bottommost partition plate and the upper surface of the middle layer partition plate, and each row of catalytic reforming region heat conduction rows includes a plurality of catalytic reforming region heat conduction ridges extending from left to right.

[0038] Furthermore, the lower surface of the reactor body is provided with a first elongated groove for embedding the heating rod and a second elongated groove for embedding the preheating tube.

[0039] The preheating tube is separately arranged and embedded in the back of the reactor through a second long groove. It works by utilizing the waste heat of the reaction process. The preheating tube can absorb the heat of the biomethanol solution during the vaporization process and evenly conduct the heat to the bottom of the reactor, so that the temperature distribution of the reactor is uniform, that is, it is mainly due to the heat conduction effect; and the temperature control device controls the temperature of the reactor body through a heating rod, so that the reactor reaches the optimal reforming temperature of the biomethanol solution.

[0040] Furthermore, the temperature control device is mainly composed of an intelligent programmable control instrument (Yuyao Changjiang temperature control instrument—XMTA-908), a thermocouple (PT-100), and a solid-state relay; the intelligent programmable control instrument, the thermocouple, the solid-state relay and the heating rod are connected in circuit, so as to realize the power supply to the heating rod, and the heating rod is used to supply heat to the microchannel hydrogen production reactor, wherein the circuit connection method of the intelligent programmable control instrument, the thermocouple, the solid-state relay and the heating rod can adopt the conventional setting in the prior art, and it is not the inventive point of the present invention, so it will not be repeated.

[0041] Furthermore, the inlet end of the microchannel hydrogen production reactor is arranged on the left side wall plate, and a reactor inlet pipe is provided at the inlet of the microchannel hydrogen production reactor, and the reactor inlet pipe is inserted into the reaction chamber from the left side wall plate.

[0042] Further preferably, the microchannel hydrogen production reactor has three inlet ports and three reactor inlet pipes.

[0043] Furthermore, an atomizing nozzle is provided at the outlet end of the reactor inlet pipe.

[0044] Furthermore, the outlet end of the microchannel hydrogen production reactor is arranged on the right side wall plate, and a reactor output pipe is provided at the outlet of the microchannel hydrogen production reactor. The reactor output pipe is inserted into the reaction chamber from the right side wall plate, and the outlet of the reactor output pipe is connected to the reactor discharge pipe.

[0045] Further, based on a general inventive concept, the present invention also provides a methanol reforming hydrogen production process using the vehicle biomethanol reforming hydrogen production reaction system, comprising the following steps:

[0046] 1) Pretreatment and preheating

[0047] Weigh a certain amount of reduced catalyst and evenly lay it on the upper surface of the bottom plate of the reactor body and the upper surface of the partition plate in the reactor body, and at the same time mix a certain amount of SiC into the catalyst; after the catalyst is laid, seal the reactor and check the sealing performance of the biomethanol reforming hydrogen production reaction system;

[0048] The heating rod is powered by a temperature control device, and the microchannel hydrogen production reactor is heated to a set temperature by the heating rod, and then the methanol in the biomethanol storage tank and the water in the water storage tank are introduced into the biomethanol solution tank through a liquid inlet flow meter and a liquid mixer in a certain proportion for full mixing to obtain a biomethanol solution, and then the biomethanol solution is introduced into the microchannel hydrogen production reactor by using a liquid pump flow meter and a pressure pump;

[0049] 2) Vaporization and catalytic conversion

[0050] The biomethanol solution passes through the gasification area, the overheating area, and the catalytic reforming area inside the microchannel hydrogen production reactor from left to right, and finally obtains the reformed gas, which is discharged from the outlet of the reactor together with the incompletely reacted biomethanol solution;

[0051] 3) Condensation, gas-liquid separation

[0052] After the reformed gas is discharged from the reactor, it is first cooled by an air cooling device, and then enters the condensation and drying device for condensation to achieve gas-liquid separation. The reformed product is first cooled to 70-80°C to separate the incompletely reacted water; the reformed product in the condensation and drying device is further cooled to below 40°C to separate the incompletely reacted biomethanol;

[0053] 4) Adsorption, purification and post-treatment:

[0054] The reformed gas after drying by the condensation drying device is introduced into the CO catalytic conversion device to convert the CO in the product into CO 2 , then enter the CO 2 In the absorption unit, CO is removed from the product 2 , purified H2 , thus completing the hydrogen production process.

[0055] Specifically, in step 1), the catalyst is a commercial catalyst, a powdered 401 copper-based catalyst provided by Sichuan Shutai Chemical Co., Ltd.; the catalyst has the advantages of high selectivity for the target product, stable structure, low reforming temperature, low price, long service life (average service life of three years), etc.; the catalyst is mainly composed of copper oxide, zinc oxide, aluminum oxide, additives, etc., wherein CuO accounts for 64.15%, ZnO accounts for 13.74%, Al 2 O 3 The proportion is 8.17%, and the rest are additives; the catalyst particle size is less than 0.6mm.

[0056] Specifically, in step 1), the total amount of catalyst used is the catalytic reforming area on the upper surface of the bottom plate of the reactor body, the upper surface of the bottommost partition plate, the upper surface of the middle layer partition plate, and the position of the topmost partition plate corresponding to the catalytic reforming area on the upper surface of the bottom plate of the reactor body. The corresponding catalyst filling amount ratio (mass ratio) is 1: (0.3-3): (0.3-3): (0.3-3), preferably 2:2:3:3, 2:3:3:2, 1:1:1:1, 3:3:2:2.

[0057] Specifically, in the process of hydrogen production by biomethanol reforming, the addition of catalyst can not only reduce the reforming temperature, increase the reforming speed and efficiency, but also improve the selectivity of the target product in the hydrogen production process. However, the price of the catalyst is relatively high, and it is easy to be sintered and deactivated at high temperature, thereby increasing the cost of hydrogen production by biomethanol reforming. The inventors found through preliminary research that mixing an appropriate amount of SiC with the catalyst can alleviate the sintering and deactivation phenomenon of the catalyst due to the high local temperature during the catalytic reforming process.

[0058] Specifically, in step 1), the total amount of catalyst used is 400 g, and the ratio of the added amount (mass) of SiC to the catalyst is (0-0.6):1, and the preferred ratios are 0.1:1, 0.2:1, 0.3:1, 0.4:1, 0.5:1, and 0.6:1.

[0059] Specifically, in step 1), the water-to-alcohol molar ratio in the biomethanol solution is (0.8-2):1, preferably 0.8:1, 1.0:1, 1.1:1, 1.2:1, 1.3:1, 1.4:1, 1.5:1, 1.6:1, 1.8:1, 2.0:1.

[0060] Specifically, in step 1), the feed flow rate of the microchannel hydrogen production reactor is 60-300 mL / min, preferably 60 mL / min, 90 mL / min, 120 mL / min, 150 mL / min, 180 mL / min, 210 mL / min, 240 mL / min, and 270 mL / min.

[0061] Specifically, in step 2), the temperature of catalytic reforming is 200-300°C, preferably 210°C, 230°C, 250°C, 270°C and 290°C.

[0062] Specifically, in step 3), the liquid inlet flow meter also has a reverse reflux function, and the incompletely reacted water is passed through the liquid inlet flow meter into the water storage tank for reuse.

[0063] Specifically, in step 3), the incompletely reacted biomethanol is separated and introduced into the biomethanol storage tank through a liquid inlet flow meter for reuse.

[0064] Specifically, in step 4), the prepared reformed gas can enter the gas online detector and the gas meter in sequence to measure the gas content and type.

[0065] Compared with the prior art, the advantages of this application are:

[0066] 1. The present invention designs a biomethanol steam reforming hydrogen production device for on-board agricultural vehicles. Through the optimization and experimental verification of the reforming hydrogen production process conditions, the hydrogen production capacity of the device is sufficient to continuously and stably provide hydrogen energy for the fuel cell system, and the fuel cell system converts hydrogen energy into kinetic energy for agricultural vehicles for use by the vehicles. This research can provide a scientific reference for further promoting the conversion of biomethanol to hydrogen energy. At the same time, it can provide a new way for the development of low-cost, efficient storage, transportation and application equipment for hydrogen energy, which has important reference value for further promoting the development and application of energy-saving and low-carbon hydrogen energy.

[0067] 2. The optimization study of methanol reforming hydrogen production process conducted by the system of the present invention found that when the catalyst bed distribution is 1:1:1:1, the feed rate is 210mL / min, the reforming temperature is 250℃, and the water-to-alcohol molar ratio of the biomethanol solution is 1.3, the system has the best hydrogen production effect. At this time, H 2 The content is 74.66%, the CO content is 0.84%, and the CO 2 The content is 24.23%, the biomethanol conversion rate is 81.87%, and the specific hydrogen production is 2175.41mL / g cat .min, and the hydrogen production rate is 2900.54mL / s. The methanol reforming hydrogen production process of the present invention is a new and environmentally friendly hydrogen production process with good promotion and application prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0068] Figure 1 is a schematic structural diagram of a biomethanol reforming hydrogen production reaction system suitable for agricultural vehicles as described in Example 1;

[0069] Figure 2 is a disassembly schematic diagram of the microchannel hydrogen production reactor described in Example 1;

[0070] Figure 3 is a top view of the reactor body described in Example 1;

[0071] Figure 4 is a bottom view of the reactor body described in Example 1;

[0072] Figure 5 is a graph showing changes in hydrogen content in Example 2;

[0073] Figure 6 is a graph showing the change in CO content in Example 2;

[0074] Figure 7 is a graph showing changes in carbon dioxide content during reforming hydrogen production in Example 2;

[0075] Figure 8 is a graph showing the change in specific hydrogen production during the hydrogen production process by steam reforming of biomethanol in Example 2;

[0076] Fig. 9 is a graph showing the change in hydrogen production rate in Example 2;

[0077] Fig.10 is a graph showing the change in biomethanol conversion rate during the reforming hydrogen production process in Example 2;

[0078] Fig.11 is a graph showing changes in hydrogen content in Example 2;

[0079] Fig.12 is a graph showing changes in carbon monoxide content in Example 2;

[0080] Fig.13 is a graph showing changes in carbon dioxide content in Example 2;

[0081] Fig.14 is a graph showing the change in specific hydrogen production in Example 2;

[0082] Fig.15 is a graph showing the change in specific hydrogen production rate in Example 2;

[0083] Fig.16 This is a graph showing the change in biomethanol conversion rate in Example 2. DETAILED DESCRIPTION

[0084] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific embodiments of the present invention are described in detail below in conjunction with the accompanying drawings. In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without violating the connotation of the present invention, so the present invention is not limited by the specific implementation disclosed below.

[0085] Example 1

[0086] like Figure 1 As shown, a biomethanol reforming hydrogen production reaction system suitable for agricultural vehicles includes a liquid inlet flow meter 3, a biomethanol solution tank 7, a microchannel hydrogen production reactor 11, an air cooling device 13, a condensation drying device 14, a CO catalytic conversion device 15, a CO 2 Absorption device 16, gas online detector 17 and gas meter 18, as well as biomethanol storage tank 1, water storage tank 2 and temperature control device (not shown in the figure);

[0087] The liquid inlet flow meter 3 is provided with a first inlet end, a second inlet end, a first outlet end and a reflux end; the liquid inlet flow meter 3 can control the flow rate of the material entering the microchannel hydrogen production reactor 11;

[0088] The outlet end of the biomethanol storage tank 1 and the outlet end of the water storage tank 2 are respectively connected to the first inlet end and the second inlet end of the liquid inlet flow meter 3 through pipelines; the water storage tank 2 contains deionized water;

[0089] A liquid mixer 5 is also provided on the pipeline connecting the liquid inlet flow meter 3 and the biomethanol solution tank 7, which can improve the mixing degree of the liquid material flowing out of the liquid inlet flow meter 3;

[0090] The pipeline connecting the biomethanol solution tank 7 and the microchannel hydrogen production reactor 11 is also provided with a liquid pump flow meter 8 and a pressure pump 9;

[0091] Specifically, the models of some of the equipment involved in this application are: the model of the liquid inlet flow meter 3 is LHZW002-02 peristaltic pump, the liquid mixer 5 is a pagoda 6mm semicircular two-way water flow meter, the model of the liquid pump flowmeter 8 is LHZW006 peristaltic pump, the model of the pressure pump 9 is VSC36A5 electromagnetic methanol pump, the model of the air cooling device 13 is JG1503-03 radiator, the model of the gas online detector 17 is MOT500-M-CL fixed composite gas detector, and the model of the gas meter 18 is G2.5 code type gas meter.

[0092] The side wall of the biomethanol solution tank 7 is also provided with a liquid level sensor 6, the liquid level sensor 6 is provided with a signal output end, and the liquid inlet flow meter 3 is provided with a signal input end. The signal output end of the liquid level sensor 6 is electrically connected to the signal input end of the liquid inlet flow meter 3 through a line, and the liquid level of the liquid material in the biomethanol solution tank 7 is detected by the liquid level sensor 6. When the liquid level is lower than the set value, the liquid level sensor 6 sends an opening signal to the liquid inlet flow meter 3, and the liquid material in the liquid inlet flow meter 3 is discharged from the first outlet end; when the liquid level in the biomethanol solution tank 7 is lower than the set value, the liquid level sensor 6 sends a closing signal to the liquid inlet flow meter 3, and the liquid inlet flow meter 3 stops discharging the liquid material; specifically, the connection between the signal output end of the liquid level sensor 6 and the signal input end of the liquid inlet flow meter 3 in this application adopts the conventional setting in the prior art, and is not the inventive point of the present invention, so it will not be repeated. The liquid level sensor 6 is a XKCY26 type patch liquid sensor.

[0093] A bypass pipe is also provided at the outlet end of the condensation and drying device 14 , and the bypass pipe is connected to the reflux end of the liquid inlet flow meter 3 .

[0094] The condensation drying device 14 is provided with a desiccant (specifically a color-changing silica gel desiccant, which has the specific function of drying the residual moisture in the reformed gas), which can dry the reformed gas after hydrogen production.

[0095] The pipeline connecting the biomethanol solution tank 7 and the microchannel hydrogen production reactor 11 is a reactor feed pipe.

[0096] Furthermore, the pipeline connecting the microchannel hydrogen production reactor 11 and the air cooling device 13 is a reactor discharge pipe, and a first valve 21 is provided on the reactor discharge pipe; a second valve 22 is provided on the pipeline connecting the air cooling device 13 and the condensation and drying device 14; and a third valve 23 is provided on the bypass pipe.

[0097] Furthermore, the liquid inlet flow meter 3 also has a reverse reflux function, and can return the incompletely reacted biomethanol and incompletely reacted water collected at the reflux end to the biomethanol storage tank 1 or the water storage tank 2 through a pipeline.

[0098] like Figure 2-4 As shown, the microchannel hydrogen production reactor 11 is a rectangular parallelepiped structure, including a reactor body 111 and a reactor cover 112. The reactor body 111 is a box-shaped structure with an open top, that is, the reactor body 111 is surrounded by a bottom plate and four side wall plates arranged at the top of the bottom plate, and a reaction chamber is formed in the middle surrounded by the bottom plate and the four side wall plates, and a plurality of partition plates are arranged in the reaction chamber; the plurality of partition plates are sequentially arranged from top to bottom, and a sealing groove structure is formed between the bottom plate of the reactor body 111 and the four side wall plates;

[0099] Further preferably, in this embodiment, three layers of partition plates are provided, and the upper surface of each layer of partition plates is a catalyst bed. The internal space between the reactor body 111 and the reactor cover 112 is divided into four layers from top to bottom by the three layers of partition plates provided in the reactor body 111, that is, the catalytic reforming space is formed between the bottom plate of the reactor body 111 and the partition plate, between the reactor cover 112 and the partition plate, and between the two adjacent layers of partition plates. From bottom to top, the height of the catalytic reforming space between the bottom plate of the reactor body 111 and the partition plate, between the two adjacent layers of partition plates, and between the reactor cover 112 and the partition plate is 7mm, 6mm, 5mm, and 5mm respectively. The height of each layer between the three partition plates is different, and the height gradually decreases from the bottom to the top. This is because after the biomethanol solution in the reactor is gasified, it will move along the top of the reactor, and the bottom is less, so the catalytic reforming space at the bottom of the reactor is set higher, and the catalytic reforming space at the top is set lower.

[0100] Specifically, the three-layer partition plate has the same front-to-back width and different left-to-right lengths, and the sizes of the three-layer partition plate from bottom to top are 400mm*180mm*3mm, 410mm*180mm*2mm, and 420mm*180mm*2mm, respectively. Figure 2 , Figure 3 The top partition plate is numbered 115, the middle partition plate is numbered 114, and the bottom partition plate is numbered 113; the lengths of each partition plate are inconsistent in order to ensure that during the reforming hydrogen production process, the vapor in the biomethanol solution can enter each catalyst bed layer separately to participate in the catalytic reforming hydrogen production reaction.

[0101] The catalytic reforming space on the upper surface of the bottom plate of the reactor body 111 is composed of a gasification area, an overheating area, and a catalytic reforming area from left to right;

[0102] The gasification region on the upper surface of the bottom plate of the reactor body 111 is provided with a plurality of gasification region heat conduction rows, and each gasification region heat conduction row includes a plurality of gasification region heat conduction ridges 116 extending from left to right; specifically, in this embodiment, the gasification region heat conduction row on the upper surface of the bottom plate of the reactor body 111 is provided with two rows on the left and the right, the left gasification region heat conduction row includes eight gasification region heat conduction ridges 116 extending from left to right, and the right gasification region heat conduction row includes nine gasification region heat conduction ridges 116 extending from left to right, and each gasification region heat conduction ridge 116 in the left gasification region heat conduction row is arranged alternately with each gasification region heat conduction ridge 116 in the right gasification region heat conduction row;

[0103] The catalytic reforming region on the upper surface of the bottom plate of the reactor body 111 is provided with a plurality of rows of catalytic reforming region heat-conducting rows, each of which includes a plurality of catalytic reforming region heat-conducting ridges 117 extending from left to right; specifically, in this embodiment, the catalytic reforming region heat-conducting rows on the upper surface of the bottom plate of the reactor body 111 are provided with two rows on the left and the right, the left catalytic reforming region heat-conducting row includes seven catalytic reforming region heat-conducting ridges 117 extending from left to right, and the right catalytic reforming region heat-conducting row includes six catalytic reforming region heat-conducting ridges 117 extending from left to right; each catalytic reforming region heat-conducting ridge 117 in the left catalytic reforming region heat-conducting row and each catalytic reforming region heat-conducting ridge 117 in the right catalytic reforming region heat-conducting row are arranged alternately;

[0104] Each gasification region heat conduction ridge 116 in the left gasification region heat conduction row and each gasification region heat conduction ridge 116 in the right gasification region heat conduction row are strip structures that rise sequentially from left to right;

[0105] The highest point on the right end of each gasification region heat conduction ridge 116 in the left gasification region heat conduction row and the highest point on the right end of each gasification region heat conduction ridge 116 in the right gasification region heat conduction row are slightly higher than or the same as the height of the catalytic reforming region heat conduction ridge 117 .

[0106] The total volume of the four-layer gasification area is 200mm*185mm*29mm, the total volume of the four-layer overheating area is 15mm*185mm*29mm, and the total volume of the four-layer catalytic reforming area is 420mm*185mm*29mm.

[0107] The front-to-rear width of each gasification region heat-conducting ridge 116 and each catalytic reforming region heat-conducting ridge 117 is 2 mm, which is used to increase the surface area, speed up the heat exchange efficiency, and improve the hydrogen production efficiency of the reactor.

[0108] The three layers of partition plates are all located above the catalytic reforming area on the upper surface of the bottom plate of the reactor body 111;

[0109] The left-right length of the bottom partition plate 113 is slightly smaller than the length of the catalytic reforming area on the upper surface of the bottom plate of the reactor body 111, the left-right length of the middle partition plate 114 is slightly larger than the left-right length of the bottom partition plate 113, and the left-right length of the top partition plate 115 is slightly larger than the left-right length of the middle partition plate 114;

[0110] Two rows of catalytic reforming region heat-conducting rows are provided on the upper surface of the bottom partition plate 113 and the upper surface of the middle partition plate 114, and each row of catalytic reforming region heat-conducting rows includes a plurality of catalytic reforming region heat-conducting ridges extending from left to right; specifically, in the present embodiment, the catalytic reforming region heat-conducting rows on the upper surface of the bottom partition plate 113 and the upper surface of the middle partition plate 114 are provided with two rows on the left and the right, the left catalytic reforming region heat-conducting row includes four catalytic reforming region heat-conducting ridges extending from left to right, and the right catalytic reforming region heat-conducting row includes three catalytic reforming region heat-conducting ridges extending from left to right; each catalytic reforming region heat-conducting ridge in the left catalytic reforming region heat-conducting row and each catalytic reforming region heat-conducting ridge in the right catalytic reforming region heat-conducting row are arranged alternately.

[0111] The size of the microchannel hydrogen production reactor 11 is 700mm*230mm*40mm. The reactor cover 112 is covered on the top of the reactor body 111. The reactor cover 112 and the four side wall plates of the reactor body 111 are provided with threaded holes, and the bottom end of the reactor cover 112 can be detachably connected to the reactor body 111 by bolts; specifically, the reactor body 111 and the reactor cover 112 are sealed with hexagon socket bolts with a diameter of 6mm to form a whole.

[0112] Since the hydrogen production reaction is an endothermic reaction, the reactor uses an external source of heat, such as Figure 4 As shown, the lower surface of the reactor body 111 is provided with a first long strip groove 118 for embedding a heating rod (not shown in the figure) and a second long strip groove 119 for embedding a preheating tube (not shown in the figure); the function of the preheating tube is to preheat the biomethanol solution entering the reactor and reduce the local temperature drop of the biomethanol solution at the feed port inside the reactor. Since the biomethanol solution is a liquid, it will absorb a lot of heat when it becomes a vapor in the vaporization area of ​​the reaction. If the biomethanol solution entering the reactor is not preheated, the biomethanol solution will vaporize from room temperature and absorb too much heat, which is not conducive to a continuous vaporization reaction.

[0113] The preheating tube is separately provided and is embedded in the back of the reactor through the second long strip groove 119. It works by utilizing the waste heat of the reaction process. The preheating tube can absorb the heat of the biomethanol solution during the vaporization process and evenly conduct the heat to the bottom of the reactor, so that the temperature distribution of the reactor is uniform, that is, it is mainly due to the heat conduction effect. The temperature control device controls the temperature of the reactor body through the heating rod, so that the reactor reaches the optimal reforming temperature of the biomethanol solution.

[0114] The first long strip groove 118 and the second long strip groove 119 both extend along the extension direction of the reactor body 111. In this embodiment, the first long strip groove 118 and the second long strip groove 119 are arranged in an interlaced manner, with two first long strip grooves 118 and three second long strip grooves 119. By embedding a heating rod in the lower surface of the reactor body 111, the microchannel hydrogen production reactor 11 can be directly contacted and heated to improve energy utilization. The heating rod is 600 mm long and has a power of 1000 W.

[0115] The temperature control device is mainly composed of an intelligent programmable control instrument (Yuyao Changjiang temperature control instrument—XMTA-908), a thermocouple (PT-100), and a solid-state relay; the intelligent programmable control instrument, the thermocouple, the solid-state relay and the heating rod are connected in circuit, so as to realize the power supply to the heating rod, and use the heating rod to heat the microchannel hydrogen production reactor 11, wherein the circuit connection method of the intelligent programmable control instrument, the thermocouple, the solid-state relay and the heating rod can adopt the conventional setting in the prior art, and it is not the inventive point of the present invention, so it will not be repeated.

[0116] The inlet end of the microchannel hydrogen production reactor 11 is arranged on the left side wall plate, and a reactor inlet pipe 10 is arranged at the inlet of the microchannel hydrogen production reactor 11, and the reactor inlet pipe 10 is inserted into the reaction chamber from the left side wall plate. Specifically, in this embodiment, the inlet end of the microchannel hydrogen production reactor 11 and the reactor inlet pipe 10 are both arranged in three, such an arrangement can increase the uniformity of the biomethanol solution entering the reactor and effectively increase the heating area of ​​the biomethanol solution;

[0117] The inlet ends of the three reactor inlet pipes 10 are connected to the reactor feed pipe, and the outlet ends of the three reactor inlet pipes 10 are all provided with atomizing nozzles 101. The atomizing nozzle 101 is a copper nozzle, and the biomethanol solution is atomized into small particles by the atomizing nozzle 101. The nozzle appearance size is 9.5mm*9mm*5mm, and the size of the atomized particles can be adjusted according to the size of the nozzle nozzle (1-8mm). When the biomethanol solution enters the reactor from the outlet ends of the three reactor inlet pipes 10, the atomizing nozzle 101 is used to make it appear in the form of tiny particles, thereby increasing the heating area of ​​the biomethanol solution at the feed port, so that the biomethanol solution is quickly gasified, and will not cause a large temperature difference in the reactor feed port area. Especially in the case of a large feed amount, the reforming efficiency of the reactor can be significantly increased.

[0118] The outlet end of the microchannel hydrogen production reactor 11 is arranged on the right side wall plate, and a reactor output pipe 12 is provided at the outlet of the microchannel hydrogen production reactor 11. The reactor output pipe 12 is inserted into the reaction chamber from the right side wall plate, and the outlet of the reactor output pipe 12 is connected to the reactor discharge pipe.

[0119] The reactor inlet pipe 10 and the reactor outlet pipe 12 are both copper pipes with a length of 50 mm and an inner diameter of 13 mm. Specifically, in this embodiment, the reactor inlet pipe 10 and the reactor outlet pipe 12 are welded to the reactor body 111, and the welding point is in a sealed state.

[0120] The operating principle of the biomethanol reforming hydrogen production reaction system suitable for agricultural vehicles is:

[0121] First, the catalyst is evenly laid on the upper surface of the bottom plate of the reactor body 111, the upper surface of the bottommost partition plate 113, the catalytic reforming area on the upper surface of the middle layer partition plate 114, and the position of the topmost partition plate 115 corresponding to the catalytic reforming area on the upper surface of the bottom plate of the reactor body 111, and then the reactor cover 112 is connected to the reactor body 111 by bolts to seal;

[0122] The catalyst used in the present invention is a commercial catalyst, a powdered 401 copper-based catalyst provided by Sichuan Shutai Chemical Co., Ltd.; the catalyst has the advantages of high selectivity for target products, stable structure, low reforming temperature, low price, long service life (average service life of three years), etc.; the catalyst is mainly composed of copper oxide, zinc oxide, aluminum oxide, additives, etc., of which CuO accounts for 64.15%, ZnO accounts for 13.74%, Al 2 O 3 The proportion of is 8.17%, and the rest is auxiliary agents;

[0123] Secondly, the temperature control device is turned on, and the microchannel hydrogen production reactor 11 is heated to a set temperature by a heating rod, and then the methanol in the biomethanol storage tank 1 and the deionized water in the water storage tank 2 are introduced into the biomethanol solution tank 7 through the liquid inlet flow meter 3 and the liquid mixer 5 for mixing to obtain a biomethanol solution, and then the biomethanol solution is introduced into the microchannel hydrogen production reactor 11 by a liquid pump flow meter 8 and a pressure pump 9, and the microchannel hydrogen production reactor 11 is vaporized and catalytically reformed to produce hydrogen to obtain a reformed gas;

[0124] The biomethanol used in the present invention is firstly prepared from corn stalks, agricultural wastes, etc. by anaerobic fermentation to produce biohydrogen, then the biohydrogen and carbon dioxide are catalytically synthesized to produce crude methanol, and finally the crude methanol is purified, see the literature (Yang Panfeng, Huang Ning, Cheng Yibu. Comparative Study on Green Methanol Production Technology [J]. Contemporary Petroleum and Petrochemicals, 2024, 32(10): 36-41; Li Jian, Zhang Zhongliang, Ma Zonghu, et al. Analysis of the Technical Route and Business Model of Deep Green Biomethanol from Biomass Biogas [J]. China Biogas, 2024, 42(4): 43-46). The biomethanol is renewable and will not cause additional carbon emissions in the entire process of hydrogen production by reforming biomethanol for automobiles. The biomethanol reaches industrial analytical purity and the content is not less than 99.5%.

[0125] The deionized water used in the present invention is prepared by RO reverse osmosis method, and other ions in the water are removed. The prepared deionized water contains only hydrogen ions and hydroxide ions, and the conductivity is lower than 0.05us / cm.

[0126] Then, the reformed gas is first cooled by the air cooling device 13, and then enters the condensation drying device 14 for condensation to achieve gas-liquid separation, and the incompletely reacted deionized water and biomethanol therein are separated, and then refluxed to the liquid inlet flow meter 3; the liquid inlet flow meter 3 also has a reverse reflux function, which can reflux the incompletely reacted biomethanol and incompletely reacted deionized water collected at the reflux end to the biomethanol storage tank 1 or the water storage tank 2 through the pipeline;

[0127] The reformed gas dried in the condensation drying device 14 is introduced into the CO catalytic converter 15 to convert the CO in the product into CO 2 , then enter the CO 2 In the absorption device 16, CO in the product is removed 2 , purified H 2 , and then enter the gas online detector 17 and the gas meter 18 in turn to measure the gas content and type.

[0128] Example 2

[0129] (I) Preparation before the experiment:

[0130] First, the overall sealing performance of the microchannel hydrogen production reactor 11 must be tested. The overall sealing performance will directly affect the efficiency of catalytic reforming hydrogen production.

[0131] Then, a certain amount of catalyst is weighed and evenly spread on the catalytic reforming area on the upper surface of the bottom plate of the reactor body 111, the upper surface of the bottom partition plate 113, the upper surface of the middle partition plate 114, and the position of the top partition plate 115 corresponding to the catalytic reforming area on the upper surface of the bottom plate of the reactor body 111, and a certain amount of SiC is mixed into the catalyst; after the catalyst is laid, the reactor is sealed and the sealing performance of the biomethanol reforming hydrogen production reaction system is tested.

[0132] Then turn on the temperature control device to heat the microchannel hydrogen production reactor 11 to a set temperature (210°C-290°C), use the liquid inlet flow meter 3 to pass the evenly mixed biomethanol solution into the reactor to activate the catalyst. After the catalyst is fully activated, catalytic reforming hydrogen production experiments can be carried out under the set reforming hydrogen production conditions.

[0133] In the process of methanol steam reforming to produce hydrogen, a variety of endothermic and exothermic reactions are involved, and the main reactions are shown below.

[0134] CH 3 OH+H 2 O→3H 2 +CO 2 ΔH=+49.5kj / mol

[0135] CH 3 OH→2H 2 +CO ΔH=+90.7 kj / mmol

[0136] H 2 +CO 2 →H 2 O+CO ΔH=-41.2 kj / mol

[0137] (II) A methanol reforming hydrogen production process using the biomethanol reforming hydrogen production reaction system suitable for agricultural vehicles described in Example 1, the specific steps are as follows:

[0138] 1) Pretreatment and preheating:

[0139] The heating rod is powered by the temperature control device, and the microchannel hydrogen production reactor 11 is heated to a set temperature (210°C-290°C) by the heating rod, and then the methanol in the biomethanol storage tank 1 and the deionized water in the water storage tank 2 are introduced into the biomethanol solution tank 7 through the liquid inlet flow meter 3 and the liquid mixer 5 in a certain proportion for sufficient mixing to obtain a biomethanol solution, and then the biomethanol solution is introduced into the microchannel hydrogen production reactor 11 by using the liquid pump flow meter 8 and the pressure pump 9.

[0140] 2) Vaporization and catalytic conversion:

[0141] The biomethanol solution passes through the gasification area, the overheating area, and the catalytic reforming area in the microchannel hydrogen production reactor 11 from left to right, that is, the biomethanol solution is gasified, overheated, and catalytically reformed in the reactor in sequence, and finally a reformed gas is obtained. The reformed gas is discharged from the outlet of the reactor together with the incompletely reacted biomethanol solution (the temperature of the reformed gas just discharged from the outlet of the reactor is basically the same as the reforming temperature. If the external temperature is low, the temperature of the reformed gas at the time of discharge is about 5-10°C lower than the reforming temperature;

[0142] At the same time, when the microchannel hydrogen production reactor 11 is preheated, the catalyst therein will be converted into an oxidized state. In the process of biomethanol reforming to produce hydrogen, the biomethanol solution will be used to reduce it. After the biomethanol solution is vaporized and contacts with the catalyst, a small amount of hydrogen will be produced, and the hydrogen can change the catalyst from an oxidized state to a reduced state.

[0143] 3) Condensation, gas-liquid separation:

[0144] After the reformed gas is discharged from the reactor, it is first cooled by the air cooling device 13, and then enters the condensation and drying device 14 for condensation to achieve gas-liquid separation. The reformed product is first cooled to 80°C to separate the incompletely reacted deionized water. The liquid inlet flow meter 3 also has a reverse reflux function, and the incompletely reacted deionized water is passed through the liquid inlet flow meter 3 into the water storage tank 2 for reuse; the reformed product in the condensation and drying device 14 is further cooled to below 40°C, the incompletely reacted biomethanol is separated, and passed through the liquid inlet flow meter 3 into the biomethanol storage tank 1 for reuse.

[0145] 4) Adsorption, purification and post-treatment:

[0146] The reformed gas dried by the desiccant in the condensation drying device 14 is introduced into the CO catalytic converter 15 to convert the CO in the product into CO as much as possible. 2 , then enter the CO 2 In the absorption device 16, CO in the product is removed 2 , to purify H 2 The purpose is to complete the hydrogen production process, and finally enter the gas online detector 17 and the gas meter 18 in sequence to measure the gas content and type.

[0147] The purified H prepared by the reforming hydrogen production process of the present invention 2 , and can subsequently be fed into the fuel cell system for use as energy, where it will be converted into electrical energy, which will provide energy for the motor, thereby providing a continuous source of power for the vehicle.

[0148] (III) Gas composition determination and data analysis

[0149] 1) The gas composition was determined using a 6820GC-14B gas chromatograph (Zhejiang Fuli Analytical Instrument Co., Ltd.) under the following chromatographic conditions: injection port temperature 100°C, column box temperature 100°C, TCD detector temperature 130°C, injection volume 500 μL, retention time 20 min, and argon as the carrier gas.

[0150] 2) Specific hydrogen production

[0151] In the process of biomethanol reforming to produce hydrogen, the specific hydrogen production is an important parameter to measure the performance of the catalyst and the reactor. The specific hydrogen production of the present invention is calculated based on the hydrogen content in the gas, the total gas output, the amount of catalyst used and the reforming time, as shown in formula (1):

[0152]

[0153] Where A is the specific hydrogen production (mL / g cat .min); is the hydrogen content in the gas (%);

[0154] V is the total gas production (mL); t is the reforming time (min); g cat is the mass of the catalyst (g);

[0155] 3) Hydrogen production rate

[0156] The hydrogen production rate is an important parameter in the present invention. The hydrogen production rate in the present invention is mainly calculated based on the hydrogen content, the total gas production and the reforming time, as shown in formula (2):

[0157]

[0158] In the formula is the hydrogen production rate (mL / s); is the hydrogen content in the gas (%);

[0159] V is the total gas production (mL); T is the reforming time (s);

[0160] 4) Biomethanol conversion rate

[0161] The biomethanol reforming hydrogen production experiment is mainly analyzed by parameters such as hydrogen content, carbon monoxide content, carbon dioxide content, specific hydrogen production, hydrogen production rate and biomethanol conversion rate. Among them, hydrogen content, carbon monoxide content and carbon dioxide content can be directly tested and analyzed by gas chromatography, specific hydrogen production and hydrogen production rate can be obtained by simple calculation of hydrogen content and total gas production volume, and biomethanol conversion rate needs to be calculated by carbon monoxide content, carbon dioxide content, total volume of reformed gas and feed amount. The biomethanol conversion rate of the present invention is solved by carbon element balance, and the biomethanol conversion rate is equal to the total carbon molar number in carbon monoxide and carbon dioxide in the reformed gas divided by the total carbon molar number in the biomethanol solution of the feed amount, as shown in formula (3):

[0162]

[0163] In the formula is the biomethanol conversion rate (%); is the total moles of carbon in carbon monoxide and carbon dioxide in the reformed gas (moL); is the mole of carbon in the feed biomethanol solution (moL).

[0164] (IV) Explore the impact of changing raw materials, catalysts, and process parameters on hydrogen production

[0165] (1) Effects of catalyst bed distribution and feed rate on hydrogen production from biomethanol reforming

[0166] The catalytic reforming area inside the microchannel hydrogen production reactor 11 is designed as a four-layer space. In the present invention, different catalyst filling amounts are set in each layer, which will affect hydrogen production. First, the catalyst filling amounts are set to 2:2:3:3, 2:3:3:2, 1:1:1:1, and 3:3:2:2 from bottom to top for research. Under different catalyst bed distribution conditions, the feed amounts are set to 60mL / min, 90mL / min, 120mL / min, 150mL / min, 180mL / min, 210mL / min, 240mL / min, and 270mL / min for reforming hydrogen production experiments. In order to avoid mutual influence of reforming hydrogen production parameters under different experimental conditions, the next set of experiments will be carried out after the previous set of experiments is completely completed.

[0167] In the process of hydrogen production by biomethanol reforming, the addition of catalyst can not only reduce the reforming temperature, increase the reforming speed and efficiency, but also improve the selectivity of the target product in the hydrogen production process. However, the price of the catalyst is relatively high, and it is easy to be sintered and deactivated under high temperature conditions, thereby increasing the cost of hydrogen production by biomethanol reforming. After preliminary research, the inventors found that mixing an appropriate amount of SiC with the catalyst can alleviate the sintering and deactivation phenomenon of the catalyst due to the high local temperature during the catalytic reforming process. Experimental conditions: catalyst particle size less than 0.6mm, reforming temperature 250℃, biomethanol solution water-to-alcohol molar ratio 1.2, catalyst dosage 80g, SiC addition amount 32g.

[0168] (2) Investigate the effects of reforming temperature and water-to-methanol molar ratio on hydrogen production from biomethanol reforming

[0169] First, biomethanol and pure water are prepared into biomethanol solutions according to different water-to-alcohol molar ratios, and the water-to-alcohol molar ratios are 1.0, 1.1, 1.2, 1.3, 1.4, 1.5, and 1.6, respectively. According to the experimental requirements, the sealing performance of the biomethanol reforming hydrogen production reaction system suitable for agricultural vehicles is tested, and the reforming hydrogen production experiment is started after the catalyst is activated.

[0170] In the research on hydrogen production from reforming of biomethanol solution with the same water-to-alcohol molar ratio, the reforming temperatures were set at 210℃, 230℃, 250℃, 270℃ and 290℃ for hydrogen production experiments. The next set of experiments was carried out after the biomethanol solution and reforming gas in the reactor were completely discharged to ensure that the biomethanol solutions with different water-to-alcohol molar ratios did not affect each other. When conducting hydrogen production experiments from reforming biomethanol solutions with the same water-to-alcohol molar ratio at different temperatures, it is also necessary to ensure that the reforming effects at different temperatures do not affect each other. After the residues in the reactor are completely discharged, the next set of experiments was carried out. Experimental conditions: catalyst particle size less than 0.6mm, catalyst dosage 80g, feed amount 210mL / min, catalyst bed distribution ratio of 1:1:1:1, SiC addition amount of 32g.

[0171] (V) Experimental results

[0172] 1. Effects of catalyst bed distribution and feed rate on hydrogen production by biomethanol reforming

[0173] In the process of hydrogen production by methanol steam reforming, the distribution of the catalyst bed directly affects the performance of the catalyst, and the catalytic performance of the catalyst directly affects the efficiency of the entire reforming hydrogen production reaction system. The amount of feed mainly affects the conversion rate of methanol. Too much feed will lead to a low methanol conversion rate, resulting in a waste of resources; too little feed can increase the methanol conversion rate, but it will lead to an increase in by-products in the product, especially an increase in CO. Therefore, in the process of hydrogen production by methanol reforming, it is necessary to set up a suitable catalyst bed and feed amount, so as to improve the efficiency of the entire reforming system.

[0174] 1.1 Effect of catalyst bed distribution and feed rate on gas content during the experiment

[0175] Depend on Figure 5 It can be seen from the hydrogen content change graph that when biomethanol reforming to produce hydrogen in the reactor, the hydrogen content under different catalyst bed distribution conditions shows a trend of first increasing and then decreasing with the increase of feed amount. When the feed amount increases from 60mL / min to 90mL / min, the hydrogen content increases faster; when the feed amount increases from 90mL / min to 210mL / min, the rate of increase of hydrogen content decreases; when the feed amount exceeds 210mL / min and continues to increase, the hydrogen content gradually decreases. This is because in the process of reforming hydrogen production, when the reforming temperature remains unchanged, the heat inside the reactor is unchanged. When the feed amount is 60mL / min at a lower level, the heat required for gasification catalytic reforming in the reactor is less, while the heat inside the reactor is more, which promotes the cracking reaction of biomethanol to produce H 2 and CO, while inhibiting the water-reverse conversion of CO to produce H 2 and CO 2 , so the hydrogen content in the product is low. When the feed rate increases to 90mL / min, due to the increase in feed rate, the heat required for gasification catalytic reforming inside the reactor increases, which causes the temperature inside the reactor to drop more, eliminating the promoting effect of the biomethanol cracking reaction and the inhibitory effect of CO water reverse conversion, so the hydrogen content in the product increases significantly. When the feed rate increases to 210mL / min, due to the gradual increase in feed rate, the heat required for gasification catalytic reforming in the reactor gradually increases, causing the temperature inside the reactor to gradually decrease. However, since the temperature inside the reactor dropped more at the beginning, the amplitude of further cooling decreased. Although the CO in the product undergoes water reverse reaction to generate H 2 and CO 2It has a promoting effect, but the effect is not particularly obvious, so the hydrogen content in the product increases slowly. When the feed rate exceeds 210mL / min and continues to increase, due to the excessive feed rate, the heat required for gasification catalytic reforming inside the reactor increases sharply, resulting in insufficient heat inside the reactor. More and more biomethanol solution is discharged from the reactor without being catalytically reformed, so the hydrogen content in the product gradually decreases.

[0176] When the feed rate is constant, the hydrogen content under different catalyst bed distribution conditions is roughly the same. Only when the feed rate increases from 90mL / min to 210mL / min, the hydrogen content is higher when the catalyst bed is distributed at 1:1:1:1 and 3:3:2:2, while the hydrogen content is lower when the catalyst bed is distributed at 2:2:3:3 and 2:3:3:2. This is because when the feed rate increases from 90mL / min to 210mL / min, the heat required for the gasification and catalytic reforming of the biomethanol solution and the heat inside the reactor are just in a dynamic equilibrium stage, and this stage has a more significant impact on the catalyst performance. According to the actual analysis of the reactor, since the biomethanol solution inside the reactor will tend to transfer to the upper end after being gasified, the catalytic reforming effect is best when the catalyst bed filling amount is evenly distributed or there is more at the bottom, and the hydrogen content is higher. At this time, the hydrogen content is higher when the catalyst bed is distributed at 1:1:1:1 and 3:3:2:2.

[0177] Depend on Figure 6 It can be seen from the graph of carbon monoxide content changes that under different catalyst bed distribution conditions, the CO content in the product shows a trend of first decreasing and then increasing with the increase in feed amount. As the feed amount of biomethanol solution increases from 60mL / min to 90mL / min, the CO content decreases faster; as the feed amount continues to increase to 210mL / min, the rate of decrease in CO content is slower; as the feed amount continues to increase beyond 210mL / min, the CO content in the product gradually increases. This is because when the reforming temperature remains unchanged, the heat inside the reactor is constant. When the feed amount is 60mL / min, there is less biomethanol solution in the reactor, and the heat required for gasification catalytic reforming is less, while the heat inside the reactor is more, far exceeding the heat required for catalytic reforming, which is not conducive to the cracking reaction of biomethanol to generate H 2 It has a promoting effect on the water-reverse conversion reaction of CO to generate H 2 and CO 2It has an inhibitory effect, so the CO content in the product is higher. As the feed rate increases to 90mL / min, the heat required for gasification catalytic reforming in the reactor increases, which will cause the temperature inside the reactor to drop, greatly alleviating the promotion effect of the biomethanol cracking reaction and the inhibitory effect of CO water reverse conversion, so the carbon monoxide content in the product is greatly reduced. As the feed rate increases to 210mL / min, the heat required for gasification catalytic reforming gradually increases, causing the temperature inside the reactor to gradually decrease. Since the temperature inside the reactor has already dropped, the extent of further cooling will decrease, although for the CO in the product to undergo water reverse reaction to generate H 2 and CO 2 It has a promoting effect, but the promoting effect is limited, so the CO content in the product decreases slowly. As the feed rate exceeds 210mL / min and continues to increase, the heat required for gasification catalytic reforming increases sharply, resulting in insufficient heat inside the reactor. The CO in the product is discharged from the reactor before it has time to undergo water reverse reaction, so the CO content in the product gradually increases.

[0178] When the feed rate is constant, the CO content under different catalyst bed distribution conditions is roughly the same. This is because the catalyst carrier distribution of the reactor is relatively appropriate. Although there are slight differences in the distribution of the catalyst filling amount, the impact on CO in the catalytic reforming hydrogen production process is small. Therefore, in the process of biomethanol reforming hydrogen production, the distribution of CO content in the product is not much different.

[0179] Depend on Figure 7 From the graph of the change of carbon dioxide content during reforming hydrogen production, it can be seen that the carbon dioxide content under different catalyst bed distribution conditions shows a trend of first increasing and then decreasing with the increase of feed amount. As the feed amount increases from 60mL / min to 90mL / min, the carbon dioxide content increases rapidly; when it continues to increase to 210mL / min, the rate of increase of carbon dioxide content slows down; when it continues to increase beyond 210mL / min, the carbon dioxide content in the product begins to gradually decrease. This is because the heat inside the reactor is constant when the reforming temperature remains unchanged. When the feed amount is as low as 60mL / min, the heat required for gasification catalytic reforming in the reactor is less. At this time, the heat inside the reactor far exceeds the heat required for catalytic reforming, which will reverse the water conversion of CO to produce H 2 and CO 2When the feed rate increases to 90 mL / min, the heat required for gasification catalytic reforming in the reactor increases, causing the temperature inside the reactor to drop, greatly alleviating the inhibitory effect of CO water reverse conversion, so the carbon dioxide content in the product increases significantly. When the feed rate increases to 210 mL / min, the heat required for gasification catalytic reforming in the reactor gradually increases. Since the temperature inside the reactor has dropped, the extent of further cooling inside the reactor is low, which is conducive to the CO water reverse reaction to generate H 2 and CO 2 The promoting effect is limited, so the carbon dioxide content in the product increases slowly. When the feed rate exceeds 210mL / min and continues to increase, the heat required for gasification catalytic reforming in the reactor increases sharply, which will lead to insufficient heat inside the reactor and reduced catalytic performance of the catalyst. More and more CO in the product is discharged from the reactor before it has time to undergo water reverse reaction, so the carbon dioxide content begins to gradually decrease.

[0180] When the feed amount is the same, the carbon dioxide content under different catalyst bed distribution conditions is roughly the same. This is because the distribution of the catalyst carrier in the reactor is more appropriate, and the distribution of the catalyst filling amount has little effect on the carbon dioxide in the hydrogen production process, so the distribution of carbon dioxide content in the product is relatively similar.

[0181] 1.2 Effect of catalyst bed distribution and feed amount on hydrogen production and hydrogen production rate

[0182] Depend on Figure 8From the variation diagram of specific hydrogen production in the process of hydrogen production by steam reforming of biomethanol, it can be seen that under different catalyst bed distribution conditions, the specific hydrogen production shows a trend of increasing first and then stabilizing with the increase of feed amount. When the feed amount increases from 60mL / min to 210mL / min, the specific hydrogen production gradually increases; when the feed amount exceeds 210mL / min and continues to increase, the specific hydrogen production gradually tends to a stable state. This is because in the process of hydrogen production by biomethanol reforming, the reforming temperature remains unchanged and the heat inside the reactor is constant. When the feed amount increases from 60mL / min to 210mL / min, the heat required for gasification catalytic reforming of biomethanol solution inside the reactor gradually increases, and when the feed amount is 210mL / min, the required heat reaches the maximum. At this time, the heat required for gasification catalytic reforming of biomethanol solution is just basically balanced with the heat inside the reactor. Therefore, when the feed rate increases from 60mL / min to 210mL / min, as the feed rate increases, the amount of biomethanol solution gasified and catalytically reformed gradually increases, the total hydrogen production gradually increases, and the specific hydrogen production gradually increases. When the feed rate exceeds 210mL / min and continues to increase, the heat required for the gasification and catalytic reforming of the biomethanol solution in the reactor continues to increase, resulting in insufficient heat inside the reactor. At this time, the heat inside the reactor can only maintain the catalytic reforming of the biomethanol solution when the feed rate is 210mL / min to produce hydrogen, and the excess biomethanol solution is discharged from the reactor, so the total hydrogen production remains basically unchanged, and the specific hydrogen production gradually tends to be stable.

[0183] When the feed amount is the same, the specific hydrogen production under different catalyst bed distribution conditions is different. When the catalyst bed distribution is 1:1:1:1, the corresponding specific hydrogen production is the highest. This is because the catalyst carrier in the reactor has been designed to fully consider the impact of temperature field and flow field on the hydrogen production process. Therefore, when the catalyst is evenly filled, the hydrogen production effect is the best and the specific hydrogen production is the highest.

[0184] Depend on Figure 8 Specific hydrogen production change diagram and Fig. 9 The hydrogen production rate change diagram shows that in the process of hydrogen production by biomethanol reforming, the hydrogen production rate change diagram and the specific hydrogen production change Figure 1 This is because the dependent variables of both are the total hydrogen production, so the factors affecting the change of hydrogen production rate are consistent with the factors affecting the change of specific hydrogen production.

[0185] 1.3 Effects of catalyst bed distribution and feed ratio on biomethanol conversion

[0186] Depend on Fig.10It can be seen from the change diagram of biomethanol conversion rate in the reforming hydrogen production process that under different catalyst bed distributions, the biomethanol conversion rate shows a gradually decreasing trend with the increase of feed amount. When the feed amount increases from 60mL / min to 210mL / min, the biomethanol conversion rate decreases slowly; when the feed amount exceeds 210mL / min and continues to increase, the biomethanol conversion rate decreases rapidly. This is because the heat inside the reactor is constant when the reforming temperature remains unchanged. When the feed amount increases from 60mL / min to 210mL / min, the heat required for gasification and catalytic reforming inside the reactor gradually increases, the temperature inside the reactor gradually decreases, and the activity of the catalyst gradually decreases. However, since the heat of the reactor is still relatively sufficient, the activity of the catalyst decreases slowly, and the biomethanol conversion rate decreases slowly. When the feed amount exceeds 210mL / min and continues to increase, the heat required for gasification and catalytic reforming of the biomethanol solution in the reactor continues to increase, resulting in insufficient heat inside the reactor. At this time, the temperature inside the reactor begins to drop significantly, resulting in a significant decrease in catalyst activity, a large reduction in the amount of biomethanol solution catalytically reformed, and a rapid decrease in the biomethanol conversion rate.

[0187] When the feed rate is constant, the biomethanol conversion rate under different catalyst bed distribution conditions is different. When the catalyst bed distribution is 1:1:1:1, the corresponding biomethanol conversion rate is the highest. This is because the catalyst filling at this time corresponds to the internal structure design of the reactor, so the catalyst has the greatest catalytic effect, the amount of biomethanol solution catalytically reformed is the largest, and the biomethanol conversion rate is the highest.

[0188] According to the hydrogen content, CO content, CO 2 The results showed that the best hydrogen production process was achieved when the catalyst bed distribution was 1:1:1:1 and the feed rate was 210 mL / min. 2 The content is 74.62%, CO content is 1.01%, CO 2 The content is 24.08%, the biomethanol conversion rate is 80.96%, and the specific hydrogen production is 2208.75mL / g cat .min, and the hydrogen production rate is 2945.00mL / s.

[0189] 2. Effects of reforming temperature and water-to-methanol molar ratio on hydrogen production from biomethanol reforming

[0190] In the process of hydrogen production by biomethanol reforming, the reforming temperature directly affects the activity of the catalyst. If the reforming temperature is too high, the catalyst will sinter and deactivate; if the reforming temperature is too low, the catalyst activity will be low and the reforming hydrogen production efficiency will be low. The water-to-alcohol molar ratio of the biomethanol solution has a great influence on the service life of the catalyst and the product selectivity. When the water-to-alcohol molar ratio is large, the heat consumption of the biomethanol solution in the gasification catalytic reforming hydrogen production process is large, which is not conducive to energy-saving production; when the water-to-alcohol molar ratio is small, the carbon content in the biomethanol solution is high, which will cover the catalyst surface and reduce the catalyst activity. Therefore, in the process of hydrogen production by biomethanol steam reforming, it is necessary to choose the appropriate reforming temperature and water-to-alcohol molar ratio.

[0191] 2.1 Effects of reforming temperature and water-to-alcohol molar ratio on the contents of various gases during the experiment

[0192] Depend on Fig.11 It can be seen from the hydrogen content change diagram that under different reforming temperature conditions, the hydrogen content in the hydrogen production process shows a trend of first increasing and then decreasing as the water-to-alcohol molar ratio of the biomethanol solution increases. This is because under the condition of a certain reforming temperature, the heat inside the reactor is certain. When the water-to-alcohol molar ratio is low, the water content in the biomethanol solution is low. Although the latent heat of vaporization of water is large, the heat inside the reactor is sufficient to enter the biomethanol solution inside the reactor for catalytic reforming and hydrogen production. As the water-to-alcohol molar ratio of the biomethanol solution gradually increases, the amount of water entering the reactor gradually increases, which will promote the reverse conversion of CO2 in the product into H 2 and CO 2, so the hydrogen content in the product gradually increases; when the water-to-alcohol molar ratio is high, the water content in the biomethanol solution increases significantly, which will cause the heat inside the reactor to be insufficient to support the complete catalytic reforming of the biomethanol solution. At the same time, the activity of the catalyst will gradually decrease due to the decrease in temperature inside the reactor, the catalytic reforming rate will slow down, and the water-reverse conversion of CO in the product will become less and less, so the hydrogen content in the product will gradually decrease. When the catalytic reforming temperature is 210℃, as the water-alcohol molar ratio increases from 1.0 to 1.2, the corresponding hydrogen content gradually increases. When the water-alcohol molar ratio continues to increase to greater than 1.2, the hydrogen content begins to gradually decrease; when the catalytic reforming temperature is 230℃, as the water-alcohol molar ratio increases from 1.0 to 1.3, the corresponding hydrogen content gradually increases. When the water-alcohol molar ratio continues to increase to greater than 1.3, the hydrogen content begins to gradually decrease; when the catalytic reforming temperatures are 250℃, 270℃, and 290℃, respectively, as the water-alcohol molar ratio increases from 1.0 to 1.4, the corresponding hydrogen content gradually increases; when the water-alcohol molar ratio continues to increase to greater than 1.4, the hydrogen content begins to gradually decrease. This is because as the reforming temperature increases, the heat inside the reactor gradually increases, and there will be enough heat to alleviate the problem of increased heat consumption caused by the increase in the water-alcohol molar ratio. Therefore, as the reforming temperature increases, the hydrogen content in the product will show a higher content under higher water-alcohol molar ratio conditions.

[0193] Under the same water-to-alcohol molar ratio, the hydrogen content in the hydrogen production process shows a trend of first increasing and then decreasing with the increase of reforming temperature. When the reforming temperature increases from 210°C to 250°C, the hydrogen content in the product gradually increases; when the reforming temperature continues to increase above 250°C, the hydrogen content in the product gradually decreases. This is because when the reforming temperature is lower than 250°C, the activity of the catalyst does not reach the highest, and the heat of the reactor does not inhibit the water reverse reaction of CO in the product. Therefore, with the increase of the reforming temperature, the catalyst activity gradually increases, the catalytic reforming rate gradually increases, and the water reverse conversion of CO is promoted, so the hydrogen content in the product gradually increases. When the reforming temperature is greater than 250°C, the activity of the catalyst basically reaches the highest at this time. Continuing to increase the reforming temperature not only fails to increase the catalyst activity, but may also cause sintering and deactivation of the catalyst. With the increase of the reforming temperature, the inhibition of the water reverse conversion reaction of CO in the product begins to gradually increase. Therefore, the hydrogen content in the product begins to gradually decrease.

[0194] Depend on Fig.12It can be seen from the carbon monoxide content change graph that the carbon monoxide content under different reforming temperature conditions shows a gradually decreasing trend with the increase of the water-to-alcohol molar ratio. This is because when the reforming temperature is constant, the heat inside the reactor is constant. Since the latent heat of gasification of water is large, the more water there is inside the reactor, the more heat required for gasification catalysis will gradually increase. As the water-to-alcohol molar ratio of the biomethanol solution gradually increases, the amount of water entering the reactor gradually increases, the heat required for gasification catalytic reforming gradually increases, and the remaining heat in the reactor gradually decreases, which will promote the reverse conversion of CO water in the product into H 2 and CO 2 , so the carbon monoxide content in the product gradually decreases.

[0195] Under the same water-to-alcohol molar ratio, the carbon monoxide content in the product shows a gradually increasing trend with the increase of reforming temperature. This is because when the water-to-alcohol molar ratio remains unchanged, the heat required for the biomethanol solution entering the reactor to produce hydrogen by gasification catalytic reforming is unchanged. As the reforming temperature gradually increases, the heat inside the reactor gradually increases, the inhibitory effect on the water reverse reaction of CO in the product gradually increases, and the carbon monoxide content in the product gradually increases. When the reforming temperature is lower than 250°C, the carbon monoxide content in the product increases less with the increase of the reforming temperature; when the reforming temperature is higher than 250°C, the carbon monoxide content in the product increases more with the increase of the reforming temperature. This is because when the reforming temperature is lower than 250°C, the heat inside the reactor is not particularly high. As the reforming temperature increases, although the heat of the reactor increases, due to the catalytic consumption of part of the heat by the gasification of the biomethanol solution inside the reactor, the remaining heat inside the reactor is less, and the inhibitory effect on the water reverse reaction of CO in the product is small. Therefore, with the increase of the reforming temperature, the carbon monoxide content in the product increases less. When the reforming temperature continues to increase above 250°C, due to the excessive heat inside the reactor, although the biomethanol gasification catalysis inside the reactor consumes part of the heat, the remaining heat is still large, which strongly inhibits the CO water reverse reaction. Therefore, as the reforming temperature increases, the carbon monoxide content in the product increases more.

[0196] Depend on Fig.13It can be seen from the carbon dioxide content change graph that in the process of hydrogen production by biomethanol reforming, the carbon dioxide content under different reforming temperature conditions shows different changing trends with the increase of the water-alcohol molar ratio of the biomethanol solution. When the reforming temperature is 210°C and 230°C, the carbon dioxide content in the product shows a trend of first increasing and then decreasing with the increase of the water-alcohol molar ratio; when the reforming temperature is 250°C, 270°C, and 290°C, the carbon dioxide content in the product shows a trend of gradually increasing with the increase of the water-alcohol molar ratio. This is because when other conditions remain unchanged, as the water-alcohol molar ratio of the biomethanol solution gradually increases, the amount of water entering the reactor gradually increases, and the heat required for gasification catalysis gradually increases, which will cause the heat inside the reactor to decrease, and CO water is reversely converted into H 2 and CO 2 The reaction is an exothermic reaction. When the reforming temperature is low at 210℃ and 230℃, there is less heat inside the reactor. As the water-to-alcohol molar ratio increases, the heat required for gasification catalytic reforming in the reactor gradually increases, which will cause the heat inside the reactor to be insufficient to support its catalytic reforming reaction. The temperature inside the reactor gradually decreases, and the catalyst activity gradually decreases, resulting in a slower catalytic reforming reaction rate, and CO is discharged from the reactor before it has time to undergo water-reverse conversion. Therefore, the carbon dioxide content in the product first increases and then decreases. When the reforming temperature is high at 250℃, 270℃, and 290℃, the heat inside the reactor is relatively sufficient. Although the heat required for gasification catalytic reforming in the reactor increases with the increase in the water-to-alcohol molar ratio, the heat inside the reactor decreases, but the heat inside the reactor is still relatively sufficient. Due to the increase in water content and the decrease in temperature in the reactor, the water-reverse conversion reaction of CO is promoted, so the carbon dioxide content in the product gradually increases.

[0197] Under the same water-to-alcohol molar ratio, the carbon dioxide content in the product shows a trend of first increasing and then decreasing with the increase of reforming temperature. When the reforming temperature increases from 210°C to 250°C, the carbon dioxide content in the product gradually increases; when the reforming temperature continues to increase above 250°C, the carbon dioxide content in the product gradually decreases. This is because when the reforming temperature is lower than 250°C, the activity of the catalyst does not reach the highest level due to the low reforming temperature, and the heat of the reactor does not inhibit the water reverse reaction of CO in the product. Therefore, as the reforming temperature increases, the catalyst activity gradually increases, the catalytic reforming rate gradually increases, and the water reverse conversion reaction time of CO increases, which will promote the water reverse conversion of CO to produce CO 2 and H 2, so the carbon dioxide content in the product gradually increases. When the reforming temperature is greater than 250°C, the activity of the catalyst basically reaches its highest point. Continuing to increase the reforming temperature will not only fail to increase the catalyst activity, but may also cause sintering and deactivation of the catalyst, reduce the catalytic reforming rate, and CO will be removed from the reactor before it has time to undergo water-reverse conversion. And as the reforming temperature increases, the inhibition of the water-reverse conversion reaction of CO in the product begins to gradually increase. Therefore, the carbon dioxide content in the product begins to gradually decrease.

[0198] 2.2 Effects of reforming temperature and water-to-methanol molar ratio on hydrogen production and rate

[0199] Depend on Fig.14 It can be seen from the change graph of specific hydrogen production that under different reforming temperature conditions, the specific hydrogen production shows a trend of first increasing and then decreasing with the increase of the water-to-alcohol molar ratio. This is because when other reforming hydrogen production conditions remain unchanged, due to the large latent heat of vaporization of water, the more water there is inside the reactor, the more heat required for gasification catalysis will gradually increase. As the water-to-alcohol molar ratio of the biomethanol solution gradually increases, the amount of water entering the reactor gradually increases, the heat required for gasification catalytic reforming gradually increases, and the remaining heat in the reactor gradually decreases. When the amount of water inside the reactor is not too much, the temperature inside the reactor does not drop much, and it will not have a significant effect on the catalyst activity. However, due to the decrease in the temperature inside the reactor and the increase in water, the reverse conversion of CO in the product to H 2 and CO 2 , so the hydrogen production gradually increases, and the specific hydrogen production gradually increases. When the amount of water inside the reactor is large, the temperature inside the reactor decreases greatly, which will have a significant impact on the activity of the catalyst, reduce the activity of the catalyst, and lead to a decrease in the catalytic reforming rate, a gradual decrease in hydrogen production, and a gradual decrease in the specific hydrogen production. Therefore, the specific hydrogen production will show a trend of increasing first and then decreasing with the increase of the water-to-alcohol molar ratio.

[0200] Under the same water-to-alcohol molar ratio, the specific hydrogen production shows a gradually increasing trend with the increase of reforming temperature. This is because under the condition of constant water-to-alcohol molar ratio, the heat required for gasification catalytic reforming hydrogen production inside the reactor is constant. As the reforming temperature gradually increases, the heat inside the reactor gradually increases, the activity of the catalyst gradually increases, the catalytic reforming rate gradually increases, and the hydrogen production gradually increases, so the specific hydrogen production gradually increases. When the reforming temperature is lower than 250°C, the specific hydrogen production increases more with the increase of the reforming temperature; when the reforming temperature is higher than 250°C, the specific hydrogen production increases less with the increase of the reforming temperature. This is because when the reforming temperature is lower than 250°C, the activity of the catalyst is low and far from the optimal activity. With the increase of the reforming temperature, the activity of the catalyst is significantly enhanced, the catalytic reforming rate is significantly increased, the hydrogen production is significantly increased, and the specific hydrogen production is significantly increased. When the reforming temperature is higher than 250°C, since the activity of the catalyst is already very close to the optimal activity, the catalyst activity does not increase significantly with the increase of the reforming temperature, the hydrogen production rate remains basically unchanged, the hydrogen output remains basically unchanged, and the specific hydrogen production remains basically unchanged.

[0201] Depend on Fig.14 and Fig.15 It can be seen that in the reforming hydrogen production process, the change trend of the specific hydrogen production and the hydrogen production rate is consistent. This is because the specific hydrogen production and the hydrogen production rate are both related to the total hydrogen production, so the influencing factors of the two are basically the same.

[0202] 2.3 Effects of reforming temperature and water-to-methanol molar ratio on biomethanol conversion

[0203] Depend on Fig.16It can be seen from the biomethanol conversion rate change diagram that the biomethanol conversion rate under different reforming temperature conditions shows different trends with the increase of the water-to-alcohol molar ratio. When the reforming temperature is lower than 250°C, the biomethanol conversion rate shows a trend of increasing first and then decreasing with the increase of the water-to-alcohol molar ratio; when the reforming temperature is higher than 250°C, the biomethanol conversion rate shows a trend of gradually increasing with the increase of the water-to-alcohol molar ratio. This is because the latent heat of vaporization of water is large. The more water there is inside the reactor, the more heat required for gasification catalysis will gradually increase. When the reforming temperature is lower than 250°C, the heat inside the reactor is not particularly high. As the water-to-alcohol molar ratio of the biomethanol solution gradually increases, the water entering the reactor gradually increases, the heat required for gasification catalytic reforming gradually increases, and the remaining heat in the reactor gradually decreases. When the amount of water inside the reactor is not too much, the temperature inside the reactor does not decrease much, and will not have a significant effect on the catalyst activity. However, due to the increase in the water-to-alcohol molar ratio, the biomethanol reforming hydrogen production reaction will be promoted, so the biomethanol conversion rate gradually increases. When there is a large amount of water inside the reactor, the temperature inside the reactor drops significantly, which will have a significant impact on the activity of the catalyst, reducing the activity of the catalyst, resulting in a decrease in the catalytic reforming rate. A lot of biomethanol solution is discharged from the reactor before it has time to react, so the biomethanol conversion rate gradually decreases.

[0204] Under the condition of constant water-to-alcohol molar ratio, the biomethanol conversion rate shows a gradually increasing trend with the increase of reforming temperature. When the reforming temperature is lower than 250℃, the biomethanol conversion rate increases more with the increase of reforming temperature; when the reforming temperature is higher than 250℃, the biomethanol conversion rate increases less with the increase of reforming temperature. This is because when the water-to-alcohol molar ratio is constant, the heat required for hydrogen production by gasification catalytic reforming inside the reactor is constant. As the reforming temperature gradually increases, the heat inside the reactor gradually increases, the activity of the catalyst gradually increases, the catalytic reforming rate gradually increases, and the amount of biomethanol solution catalytically converted gradually increases, so the biomethanol conversion rate gradually increases. When the reforming temperature is lower than 250℃, since the activity of the catalyst is far from the optimal activity, as the reforming temperature increases, the activity of the catalyst is significantly enhanced, the catalytic reforming rate is significantly increased, and the biomethanol conversion rate is significantly increased. When the reforming temperature is higher than 250℃, since the activity of the catalyst is already very close to the optimal activity, as the reforming temperature increases, the catalyst activity does not increase significantly, so the biomethanol conversion rate remains basically unchanged.

[0205] According to the hydrogen content, CO content, CO 2 The results showed that the hydrogen production process was optimal when the reforming temperature was 250 °C and the water-to-alcohol molar ratio of the biomethanol solution was 1.3.2 The content is 74.66%, CO content is 0.84%, CO 2 The content is 24.23%, the biomethanol conversion rate is 81.87%, and the specific hydrogen production is 2175.41mL / g cat .min, and the hydrogen production rate is 2900.54mL / s.

[0206] The present invention mainly optimizes the methanol reforming hydrogen production process of the biomethanol reforming hydrogen production reaction system suitable for agricultural vehicles, and uses the response surface methodology to analyze the effects of different process conditions on reforming hydrogen production, and screens out the optimal reforming hydrogen production conditions for the system. The main conclusions are as follows:

[0207] The optimization study of methanol reforming hydrogen production process in the system found that: 2 The system was optimized for the following conditions: CO content, CO content, hydrogen production rate, and biomethanol conversion rate. The results showed that the system had the best hydrogen production effect when the catalyst bed distribution was 1:1:1:1, the feed rate was 210 mL / min, the reforming temperature was 250 °C, and the water-to-alcohol molar ratio of the biomethanol solution was 1.3. 2 The content is 74.66%, the CO content is 0.84%, and the CO 2 The content is 24.23%, the biomethanol conversion rate is 81.87%, and the specific hydrogen production is 2175.41mL / g cat .min, and the hydrogen production rate is 2900.54mL / s.

Claims

1. A vehicle-use biomethanol reforming hydrogen production reaction system, characterized in that: It includes a liquid inlet flow meter, a biomethanol solution tank, a microchannel hydrogen production reactor, an air cooling device, a condensation drying device, a CO catalytic conversion device, a CO2 absorption device, a biomethanol storage tank, a water storage tank and a temperature control device which are sequentially connected through pipelines; The liquid inlet flow meter is provided with a first inlet end, a second inlet end and a first outlet end; the liquid inlet flow meter can control the flow rate of the material entering the microchannel hydrogen production reactor; The outlet end of the biomethanol storage tank and the outlet end of the water storage tank are respectively connected to the first inlet end and the second inlet end of the liquid inlet flow meter through pipelines; The pipeline connecting the biomethanol solution tank and the microchannel hydrogen production reactor is the reactor feed pipe; The pipeline connecting the microchannel hydrogen production reactor and the air cooling device is the reactor discharge pipe; The microchannel hydrogen production reactor is a rectangular parallelepiped structure, including a reactor body and a reactor cover. The reactor body is surrounded by a bottom plate and four side wall plates arranged on the top of the bottom plate. A reaction chamber is formed in the middle surrounded by the bottom plate and the four side wall plates. A plurality of partition plates are arranged in sequence from top to bottom. The reactor cover is arranged on the top of the reactor body, and the reactor cover is detachably connected to the reactor body.

2. The vehicle biomethanol reforming hydrogen production reaction system according to claim 1, characterized in that: The vehicle biomethanol reforming hydrogen production reaction system also includes a gas online detector and a gas meter; the feed end of the gas online detector is connected to the discharge end of the CO2 absorption device through a pipeline, and the discharge end of the gas online detector is connected to the feed end of the gas meter through a pipeline.

3. The vehicle biomethanol reforming hydrogen production reaction system according to claim 1, characterized in that: A liquid level sensor is also provided on the side wall of the biomethanol solution tank. The liquid level sensor is provided with a signal output end, and the liquid inlet flow meter is provided with a signal input end. The signal output end of the liquid level sensor is electrically connected to the signal input end of the liquid inlet flow meter through a circuit, and the liquid level of the liquid material in the biomethanol solution tank is detected by the liquid level sensor.

4. The vehicle biomethanol reforming hydrogen production reaction system according to claim 1, characterized in that: The partition plate is provided with three layers; the internal space between the reactor body and the reactor cover is divided into four layers from top to bottom by the three-layer partition plate provided in the reactor body, namely, a catalytic reforming space is formed between the bottom plate of the reactor body and the partition plate, between the reactor cover and the partition plate, and between two adjacent layers of partition plates above and below; the three-layer partition plate has the same front and rear width and different left and right lengths.

5. The vehicle biomethanol reforming hydrogen production reaction system according to claim 1, characterized in that: The catalytic reforming space on the upper surface of the bottom plate of the reactor body is composed of the gasification area, the overheating area, and the catalytic reforming area from left to right; The gasification area on the upper surface of the bottom plate of the reactor body is provided with a plurality of gasification area heat conduction rows, each of which includes a plurality of gasification area heat conduction ridges extending from left to right; The catalytic reforming region on the upper surface of the bottom plate of the reactor body is provided with a plurality of rows of catalytic reforming region heat conducting rows, each of which comprises a plurality of catalytic reforming region heat conducting ridges extending from left to right.

6. The vehicle biomethanol reforming hydrogen production reaction system according to claim 1, characterized in that: The lower surface of the reactor body is provided with a first long strip groove for embedding the heating rod and a second long strip groove for embedding the preheating tube.

7. The vehicle biomethanol reforming hydrogen production reaction system according to claim 1, characterized in that: The inlet end of the microchannel hydrogen production reactor is arranged on the left side wall plate, and a reactor inlet pipe is arranged at the inlet of the microchannel hydrogen production reactor, and the reactor inlet pipe is inserted into the reaction chamber from the left side wall plate; The outlet end of the microchannel hydrogen production reactor is arranged on the right side wall plate, and a reactor output pipe is arranged at the outlet of the microchannel hydrogen production reactor. The reactor output pipe is inserted into the reaction chamber from the right side wall plate, and the outlet of the reactor output pipe is connected with the reactor discharge pipe.

8. A methanol reforming hydrogen production process using the vehicle biomethanol reforming hydrogen production reaction system according to any one of claims 1 to 7, characterized in that: The steps include: 1) Pretreatment and preheating Weigh a certain amount of reduced catalyst and evenly lay it on the upper surface of the bottom plate of the reactor body and the upper surface of the partition plate in the reactor body, and at the same time mix a certain amount of SiC into the catalyst; after the catalyst is laid, seal the reactor and check the sealing performance of the biomethanol reforming hydrogen production reaction system; The heating rod is powered by a temperature control device, and the microchannel hydrogen production reactor is heated to a set temperature by the heating rod, and then the methanol in the biomethanol storage tank and the water in the water storage tank are introduced into the biomethanol solution tank through a liquid inlet flow meter and a liquid mixer in a certain proportion for full mixing to obtain a biomethanol solution, and then the biomethanol solution is introduced into the microchannel hydrogen production reactor by using a liquid pump flow meter and a pressure pump; 2) Vaporization and catalytic conversion The biomethanol solution passes through the gasification area, the overheating area, and the catalytic reforming area inside the microchannel hydrogen production reactor from left to right, and finally obtains the reformed gas, which is discharged from the outlet of the reactor together with the incompletely reacted biomethanol solution; 3) Condensation, gas-liquid separation After the reformed gas is discharged from the reactor, it is first cooled by an air cooling device, and then enters the condensation and drying device for condensation to achieve gas-liquid separation. The reformed product is first cooled to 70-80°C to separate the incompletely reacted water; the reformed product in the condensation and drying device is further cooled to below 40°C to separate the incompletely reacted biomethanol; 4) Adsorption, purification and post-treatment: The reformed gas dried by the condensation and drying device is introduced into the CO catalytic conversion device to convert the CO in the product into CO2, and then enters the CO2 absorption device to remove the CO2 in the product and purify the H2, thus completing the hydrogen production process.

9. The process according to claim 8, characterized in that In step 1), the water-alcohol molar ratio in the biomethanol solution is (0.8-2):1; in step 1), the feed flow rate of the microchannel hydrogen production reactor is 60-300 mL / min.

10. The process according to claim 8, characterized in that In step 2), the temperature of catalytic reforming is 200-300°C.

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