Methanol hydrogen production system with carbon dioxide trapping and circulating heat supply functions

Abstract

The utility model relates to the technical field of methanol hydrogen production, in particular to a methanol hydrogen production system capable of capturing carbon dioxide and circularly supplying heat, which is characterized in that the output end of a methanol water supply system is connected with the tube pass input end of a reforming reactor through a pipeline, and the output end of the reforming reactor is connected with the input end of an alloy membrane system through a pipeline; the alloy membrane system is provided with two output ends, the first output end of the alloy membrane system is a hydrogen discharge pipeline, the second output end of the alloy membrane system is connected with the input end of the catalytic oxidation reactor through a pipeline, and the output end of the catalytic oxidation reactor is connected with the input end of a shell pass of the reforming reactor. And the output end of the shell pass of the reforming reactor, the by-product discharge end and the output end of the combustion-supporting gas input equipment are connected with the input end of the catalytic oxidation reactor through pipelines. According to the methanol-to-hydrogen system, heat generated by high-temperature catalytic oxidation of tail gas discharged by methanol-to-hydrogen purification is used as heat required by a process, so that energy consumption is effectively reduced, and emission of carbon dioxide tail gas is reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of methanol hydrogen production, in particular to a methanol hydrogen production system with the functions of capturing carbon dioxide and circulating heat supply. Background Art

[0002] The methanol hydrogen production process is an endothermic reaction. Most of the heat required by the existing methanol hydrogen production technology is continuously provided by the outside world. At present, the main heating methods for methanol hydrogen production technology are as follows:

[0003] A Chinese patent (application number 200910311040.7) discloses a methanol-water vapor hydrogen production process using catalytic combustion flue gas as a heat source. The exhaust gas from methanol-hydrogen production contains hydrogen, and catalytic combustion is used to provide heat, which is then transferred to heat transfer oil. The heat transfer oil system has large heat losses during transportation, and the heating temperature of the heat transfer oil is limited.

[0004] A Chinese patent (application number 202011577832.1) discloses a method of using the exhaust gas from methanol to produce hydrogen to catalytically burn with air to provide heat for the reaction. Although the system has no open flame, a combustion system is still required, which poses certain safety risks.

[0005] A device for treating hydrogen-containing exhaust gas by low-temperature catalytic oxidation disclosed in a Chinese invention patent (application number 201810019696.0) is only suitable for exhaust gas containing hydrogen, and has no effective control over the oxygen content after mixing, which is prone to explosion.

[0006] A Chinese patent (application number 201610302025.6) discloses a method of using high-temperature and high-pressure steam to provide heat for a methanol reforming reactor. However, its heating system still requires a high-temperature circulation pump to maintain a closed circulation of the steam, which increases the operating cost of the system. Utility Model Content

[0007] In order to solve the above problems, the utility model proposes a methanol hydrogen production system with carbon dioxide capture and circulating heat supply. The methanol hydrogen production system uses the heat generated by high-temperature catalytic oxidation of the tail gas discharged from the methanol hydrogen purification to provide the heat required for the process, thereby effectively reducing energy consumption; at the same time, the carbon dioxide tail gas generated by catalytic oxidation is captured to reduce or even eliminate carbon dioxide emissions.

[0008] In order to achieve the above purpose, the technical solution adopted by the utility model is:

[0009] A methanol hydrogen production system with carbon dioxide capture and circulating heat supply comprises a methanol water supply system, a reforming reactor, an alloy membrane system, a catalytic oxidation reactor and a combustion-supporting gas input device, wherein the output end of the methanol water supply system is connected to the tube side input end of the reforming reactor through a pipeline, the output end of the reforming reactor is connected to the input end of the alloy membrane system through a pipeline, the alloy membrane system has two output ends, the first output end of the alloy membrane system is a hydrogen discharge pipeline, the second output end of the alloy membrane system is connected to the input end of the catalytic oxidation reactor through a pipeline, the output end of the catalytic oxidation reactor is connected to the shell side input end of the reforming reactor, the shell side output end of the reforming reactor is a byproduct discharge end, and the output end of the combustion-supporting gas input device is connected to the input end of the catalytic oxidation reactor through a pipeline.

[0010] Preferably, the methanol water supply system comprises a methanol-water integrated machine and a metering pump, wherein the output end of the methanol-water integrated machine is connected to the input end of the metering pump, and the output end of the metering pump is connected to the input end of the reforming reactor tube.

[0011] Preferably, the combustion-supporting gas input device is an air blower.

[0012] Preferably, the methanol hydrogen production system with carbon dioxide capture and circulating heat supply also includes a multi-stage heat exchanger, and the pipeline between the methanol water supply system and the input end of the reforming reactor tube side passes through the first heat exchange pipeline of the multi-stage heat exchanger, and the shell side output end of the reforming reactor is connected to the second heat exchange pipeline of the multi-stage heat exchanger through a pipeline.

[0013] Preferably, the methanol-to-hydrogen system with carbon dioxide capture and circulating heat supply also includes a by-product recovery and circulation device, which also includes a condenser and a carbon dioxide capture system. The output end of the reforming reactor is connected to the input end of the condenser, and the input end of the carbon dioxide capture system is connected to the condenser to capture the carbon dioxide in the condensed gas, and the output end of the condenser is connected to the combustion-supporting gas input device through a pipeline.

[0014] The beneficial effects of using the utility model are:

[0015] This methanol hydrogen production system reforms methanol water through a reforming reactor, and the obtained products are classified by an alloy membrane system. The separated hydrogen is discharged from the system, and the remaining by-products enter the catalytic oxidation reactor to produce an exothermic oxidation reaction with air. The high-temperature by-product gas output by the catalytic oxidation reactor is used as a heat source for the multi-stage heat exchanger and the reforming reactor. The by-product gas after heating captures carbon dioxide and then mixes with air before entering the catalytic oxidation reactor to participate in the cycle. This methanol hydrogen production system has the advantages of small heat loss, no open flame, and no need to add additional water vapor. The exhaust gas discharged from the methanol hydrogen production purification uses the heat generated by high-temperature catalytic oxidation to provide the heat required for the process, effectively reducing energy consumption; at the same time, it can capture carbon dioxide exhaust gas to reduce or eliminate greenhouse gas emissions. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 A simplified diagram of a methanol-to-hydrogen system with carbon dioxide capture and cycle heat supply.

[0017] Reference numerals include:

[0018] 1-alcohol-water integrated machine, 2-metering pump, 3-multi-stage heat exchanger, 4-reforming reactor, 5-alloy membrane system, 6-catalytic oxidation reactor, 7-carbon dioxide capture system, 8-air fan, 9-condenser, 10-hydrogen exhaust pipeline. DETAILED DESCRIPTION

[0019] In order to make the purpose, technical solution and advantages of the technical solution more clear, the technical solution is further described in detail below in conjunction with specific implementation methods. It should be understood that these descriptions are only exemplary and are not intended to limit the scope of the technical solution.

[0020] In order to solve the problem that the methanol hydrogen production system in the prior art requires additional heating and the carbon dioxide tail gas is directly discharged, Figure 1 As shown, this embodiment proposes a methanol hydrogen production system with carbon dioxide capture and circulating heat supply, which is mainly far away from the input end as an alcohol-water integrated machine 1, and the output end of the alcohol-water integrated machine 1 is connected to a metering pump 2 through a pipeline. The metering pump 2 is used as a power device for pumping out methanol water and can detect the total output of methanol water. The output end of the metering pump 2 is connected to the first heat exchange pipeline of the multi-stage heat exchanger 3 through a pipeline. The methanol water enters the pipe input end of the reforming reactor 4 after preheating. After the high-temperature catalytic reaction in the reforming reactor 4, the methanol water is decomposed into hydrogen and other gaseous byproducts, and other gaseous byproducts include gases such as carbon dioxide. The above-mentioned mixed gas of hydrogen and other gaseous byproducts enters the alloy membrane system 5, and after separation by the alloy membrane in the alloy membrane system 5, the hydrogen is discharged from the hydrogen discharge pipeline 10 alone.

[0021] The other output end of the alloy membrane system 5 is connected to the input end of the catalytic oxidation reactor 6 through a pipeline, and the above-mentioned other gaseous byproducts enter the catalytic oxidation reactor 6. In addition, the output end of the air blower 8 is connected to the input end of the catalytic oxidation reactor 6 through a pipeline. The oxidizable gases in the other gaseous byproducts and the air are fully oxidized and release heat in the catalytic oxidation reactor 6, and the generated high-temperature gases include gaseous carbon dioxide, water vapor, and unoxidized gases (such as nitrogen). The output end of the catalytic oxidation reactor 6 is connected to the input end of the shell side of the reforming reactor 4 through a pipeline. After the high-temperature gas is input into the shell side of the reforming reactor 4, it serves as a heat source for the reforming reactor 4. Since the reaction of methanol water in the reforming reactor 4 is an endothermic reaction, the temperature of the above-mentioned high-temperature gas is reduced after being discharged from the output end of the shell side of the reforming reactor 4, but it still maintains a relatively high temperature.

[0022] The output end of the shell side of the reforming reactor 4 is connected to the second heat exchange pipeline of the multi-stage heat exchanger 3 through a pipeline, and the higher temperature gas is exchanged with the methanol water input into the reforming reactor 4. Therefore, the high-temperature gas output by the catalytic oxidation reactor 6 in this embodiment undergoes heat exchange twice, and the heat is fully utilized to minimize the overall heat loss of the system.

[0023] The output end of the second heat exchange pipeline of the multistage heat exchanger 3 is connected to the input end of the condenser 9 through a pipeline. The gas output from the second heat exchange pipeline of the multistage heat exchanger 3 includes water vapor, carbon dioxide gas and unoxidized gas at a relatively high temperature. The water vapor, carbon dioxide gas and unoxidized gas enter the condenser 9, and most of the water vapor is condensed and discharged. The carbon dioxide gas is captured by the carbon dioxide capture system 7 and purified to obtain a carbon dioxide product. The remaining part of the gas still has a high heat content. The remaining part of the gas is mixed with the air supplied by the air blower 8 and preheated, and then mixed with the tail gas discharged from the alloy membrane system 5 to enter the catalytic oxidation cycle.

[0024] The methanol hydrogen production system reforms methanol water through the reforming reactor 4, and the obtained products are classified through the alloy membrane system 5. The separated hydrogen is discharged from the system, and the remaining by-products enter the catalytic oxidation reactor 6 to produce an exothermic oxidation reaction with the air. The by-product high-temperature gas output by the catalytic oxidation reactor 6 is used as a heat source for the multi-stage heat exchanger 3 and the reforming reactor 4. The by-product gas after heating captures carbon dioxide and then mixes with air and enters the catalytic oxidation reactor 6 to participate in the cycle. The methanol hydrogen production system has small heat loss, no open flame, and no need to add additional water vapor. The exhaust gas discharged from the methanol hydrogen production purification uses the heat generated by high-temperature catalytic oxidation to provide the heat required for the process, effectively reducing energy consumption; at the same time, it can capture carbon dioxide exhaust gas to reduce or eliminate greenhouse gas emissions.

[0025] The above contents are only preferred embodiments of the present invention. For ordinary technicians in this field, many changes can be made in the specific implementation methods and application scopes based on the ideas of the present technical content. As long as these changes do not deviate from the concept of the present invention, they all fall within the scope of protection of this patent.

Claims

1. A methanol hydrogen production system with carbon dioxide capture and circulating heat supply, characterized in that: The invention comprises a methanol water supply system, a reforming reactor, an alloy membrane system, a catalytic oxidation reactor and a combustion-supporting gas input device, wherein the output end of the methanol water supply system is connected to the tube side input end of the reforming reactor through a pipeline, the output end of the reforming reactor is connected to the input end of the alloy membrane system through a pipeline, the alloy membrane system has two output ends, the first output end of the alloy membrane system is a hydrogen discharge pipeline, the second output end of the alloy membrane system is connected to the input end of the catalytic oxidation reactor through a pipeline, the output end of the catalytic oxidation reactor is connected to the shell side input end of the reforming reactor, the shell side output end of the reforming reactor is a byproduct discharge end, and the output end of the combustion-supporting gas input device is connected to the input end of the catalytic oxidation reactor through a pipeline.

2. The methanol-to-hydrogen system according to claim 1, characterized in that: The methanol water supply system comprises a methanol-water integrated machine and a metering pump, wherein the output end of the methanol-water integrated machine is connected to the input end of the metering pump, and the output end of the metering pump is connected to the input end of the reforming reactor tube.

3. The methanol-to-hydrogen system according to claim 1, characterized in that: The combustion-supporting gas input device is an air blower.

4. The methanol-to-hydrogen system according to claim 1, characterized in that: The methanol hydrogen production system with carbon dioxide capture and circulating heat supply also includes a multi-stage heat exchanger. The pipeline between the methanol water supply system and the input end of the reforming reactor tube side passes through the first heat exchange pipeline of the multi-stage heat exchanger, and the shell side output end of the reforming reactor is connected to the second heat exchange pipeline of the multi-stage heat exchanger through a pipeline.

5. The methanol to hydrogen system according to any one of claims 1 to 4, characterized in that: The methanol-to-hydrogen system with carbon dioxide capture and circulating heat supply also includes a by-product recovery and circulation device, which also includes a condenser and a carbon dioxide capture system. The output end of the reforming reactor is connected to the input end of the condenser, and the input end of the carbon dioxide capture system is connected to the condenser to capture carbon dioxide in the condensed gas. The output end of the condenser is connected to the combustion-supporting gas input device through a pipeline.

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