A methanol hydrogen production system

Abstract

The utility model discloses a kind of methanol hydrogen production systems, including methanol hydrogen production unit, the hydrogen production unit includes heater and reforming reactor, the hydrogen production unit also includes multiple flow heat exchanger, the multiple flow heat exchanger includes first inlet, second inlet, third inlet, fourth inlet and first outlet, second outlet, third outlet, fourth outlet;The first inlet is imported methanol water mixed solution;The first outlet is communicated with the material inlet of the reforming reactor;The second inlet is communicated with fourth outlet, the second outlet is communicated with the hot medium inlet of the reforming reactor, the third inlet is communicated with the reforming mixed gas outlet of the reforming reactor;The fourth inlet is communicated with the hot medium outlet of the reforming reactor.In methanol hydrogen production unit, multiple flow heat exchanger is used to carry out heat energy exchange, not only reduce the floor area of methanol hydrogen production unit, also improve heat exchange efficiency.

Description

Technical Field

[0001] This utility model relates to the field of methanol-to-hydrogen, and specifically to a methanol-to-hydrogen system. Background Technology

[0002] With the maturation and stabilization of methanol-to-hydrogen technology, the hydrogen energy industry has seen widespread promotion and application. Currently, the application of hydrogen energy is not limited to vehicles, distributed power generation, and ships; it is also being used as an energy substitute in industrial applications, especially in the last two years in industries such as hydrogen metallurgy, kilns, heat treatment, and incineration. However, the methanol-to-hydrogen process requires a large amount of heat energy to meet the reaction conditions, and the reaction also produces a large amount of carbon dioxide.

[0003] Existing technologies have developed solutions for recovering and reusing the heat generated in the reforming hydrogen production reaction through waste heat recovery devices. For example, patent CN221334236U discloses a methanol-to-hydrogen device, which uses three heat exchangers to preheat and vaporize methanol-water, thereby bringing the methanol-water to the reaction temperature. However, this device has a large number of heat exchangers, and the pipelines connecting the heat exchangers are also relatively long, which not only increases the footprint of the methanol-to-hydrogen device, but also increases heat loss during transportation. Utility Model Content

[0004] To address the issues of low thermal energy utilization and carbon dioxide emissions in existing technologies, this utility model provides the following technical solution:

[0005] A methanol-to-hydrogen system includes a methanol-to-hydrogen unit, which includes a heater and a reforming reactor. The unit also includes a multi-stream heat exchanger with a first inlet, a second inlet, a third inlet, a fourth inlet, and a first outlet, a second outlet, a third outlet, and a fourth outlet. A methanol-water mixture is introduced through the first inlet. The first outlet is connected to the material inlet of the reforming reactor. The second inlet is connected to the fourth outlet and to the heat medium inlet of the reforming reactor. The third inlet is connected to the reformed mixed gas outlet of the reforming reactor. The fourth inlet is connected to the heat medium outlet of the reforming reactor.

[0006] Preferably, the methanol-to-hydrogen system further includes a carbon dioxide recovery unit, which includes an absorption tower and a carbon dioxide capture system; the absorption tower includes a mixed gas inlet, a tail gas outlet, and a purified gas outlet; the third outlet flows into the mixed gas inlet; and the tail gas outlet is connected to the carbon dioxide capture system.

[0007] Preferably, the methanol-to-hydrogen unit further includes a condenser and a first gas-liquid separator connected in series, and the third outlet is connected to the mixed gas inlet via the condenser.

[0008] Preferably, the carbon dioxide capture system includes a carbon dioxide purification unit and a carbon dioxide compression unit; the carbon dioxide purification unit includes a regeneration tower, a first chiller and a second gas-liquid separator connected in sequence, and a reboiler connected to the regeneration tower.

[0009] Preferably, the regeneration tower includes a rich liquid inlet, a carbon dioxide outlet, a circulation inlet, and a circulation outlet. The rich liquid inlet is connected to the tail gas outlet. The reboiler includes a heating inlet, a heating outlet, and a lean liquid outlet. The circulation outlet is connected to the heating inlet, and the circulation inlet is connected to the heating outlet.

[0010] Preferably, the carbon dioxide purification unit further includes an amine recovery device, which includes a second water cooler and an amine storage tank; one end of the second water cooler is connected to the lean liquid outlet, and the other end is connected to the amine storage tank.

[0011] Preferably, the absorption tower further includes an amine liquid inlet, and the amine liquid tank includes a lean liquid inlet and an amine liquid outlet, with the amine liquid outlet connected to the amine liquid inlet.

[0012] Preferably, the amine recovery device further includes a first heat exchanger and a transfer pump; the transfer pump is located between the amine storage tank and the absorption tower, and the first heat exchanger is located between the absorption tower and the regeneration tower.

[0013] Preferably, the methanol-to-hydrogen system further includes a hydrogen collection device, which includes an alkylator and a third gas-liquid separator connected in sequence; the alkylator is connected to the purified gas outlet.

[0014] Preferably, the methanol-to-hydrogen unit further includes a heat medium circulation device, which includes a cooler, a flow regulating valve, and a third heat exchanger. The third heat exchanger is used to exchange heat between the heat medium flowing out of the multi-stream heat exchanger and the heat medium flowing into the multi-stream heat exchanger.

[0015] Compared with the prior art, the present invention has the following beneficial effects:

[0016] The use of a multi-flow heat exchanger in the methanol-to-hydrogen unit not only reduces the unit's footprint but also improves heat exchange efficiency. Simultaneously, the recovery of carbon dioxide from the hydrogen production tail gas reduces production costs. Attached Figure Description

[0017] Figure 1 This is a flowchart of the methanol-to-hydrogen system of this utility model;

[0018] Figure 2 This is a flow chart of the methanol-to-hydrogen unit of this utility model;

[0019] Figure 3 This is a flow chart of the methanol-water conveying device for the methanol-to-hydrogen unit of this utility model. Detailed Implementation

[0020] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0021] Example 1:

[0022] This embodiment provides a methanol-to-hydrogen system, such as Figure 1 As shown, it includes a methanol-to-hydrogen unit and a carbon dioxide recovery unit; the methanol-to-hydrogen unit is used to obtain reformed mixed gas; the carbon dioxide recovery unit is used to obtain purified hydrogen and high-purity carbon dioxide.

[0023] Specifically, the methanol-to-hydrogen unit includes a multi-stream heat exchanger 1, a heater 2, and a reforming reactor 3. The multi-stream reactor 1 is used to recover and reuse the heat energy in the methanol-to-hydrogen unit. The heater 2 is used to heat the heat medium in the methanol-to-hydrogen unit to provide heat energy for methanol-to-hydrogen production. The reforming reactor 3 is used to carry out the methanol-to-hydrogen reaction.

[0024] The multi-stream heat exchanger 1 includes a first inlet 11, a second inlet 12, a third inlet 13, a fourth inlet 14, a first outlet 15, a second outlet 16, a third outlet 17, and a fourth outlet 18. The reforming reactor 3 includes a material inlet 31, a reformed mixed gas outlet 32, a heat medium inlet 33, and a heat medium outlet 34. A methanol-water mixture is introduced through the first inlet 11, and the first outlet 15 is connected to the material inlet 31. The second inlet 12 is connected to the fourth outlet 18, and the second outlet 16 is connected to the heat medium inlet 33. The third inlet 13 is connected to the reformed mixed gas outlet 32, and the third outlet 17 is connected to equipment in the next process. The fourth inlet 14 is connected to the heat medium outlet 34, and the fourth outlet 18 is connected to the second inlet 12. Additionally, a heater 2 is located in the pipeline between the second outlet 16 and the heat medium inlet 33 for heating the heat medium.

[0025] In this technical solution, the flow path of the methanol-water mixture is: methanol-water mixture → first inlet 11 → first outlet 15 → material inlet 31. After being heated into methanol-water vapor in the multi-stream heat exchanger 1, the methanol-water mixture flows into the reforming reactor 3 and undergoes a reforming reaction in the reforming reactor 3 to obtain reformed mixed gas. The flow path of the reformed mixed gas is: reforming reactor 3 → reformed mixed gas outlet 32 ​​→ third inlet 13 → third outlet 17 → next process equipment. The circulating flow path of the heat medium in this unit is: heat medium → second inlet 12 → second outlet 16 → heater 2 → heat medium inlet 33 → heat medium outlet 34 → fourth inlet 14 → fourth outlet 18 → second inlet 12. During operation, the methanol-water mixture first exchanges heat with the still-warm hot medium flowing out of the reforming reactor 3 in the multi-stream heat exchanger 1, and then exchanges heat with the high-temperature reforming gas mixture to further vaporize the methanol-water mixture. After heat exchange, the hot medium is heated by the heater 2 and then flows into the reforming reactor 3 to provide heat energy for the reforming reaction.

[0026] In addition, the methanol-to-hydrogen unit also includes a condenser 35 and a first gas-liquid separator 36; the condenser 35 is used to further cool the reformed gas mixture to meet the temperature requirements of the next process; the gas-liquid separator 36 is used to separate the liquid in the cooled reformed gas mixture.

[0027] The carbon dioxide recovery unit includes an absorption tower 4 and a carbon dioxide capture system. The absorption tower 4 includes a mixed gas inlet 41, a tail gas outlet 42, and a purified gas outlet 43. The tail gas outlet 42 is located at the bottom of the absorption tower 4, and the purified gas outlet 43 is located at the top of the absorption tower 4. The mixed gas inlet 41 is used to introduce reformed mixed gas. In this embodiment, the mixed gas inlet 41 is connected to the third outlet 17 of the multi-stream heat exchanger 1. The tail gas outlet 42 is connected to the carbon dioxide capture system, and the purified gas outlet 43 is connected to the equipment of the next process. During operation, the reformed mixed gas flows into the carbon dioxide recovery unit through the mixed gas inlet 41. After separation in the absorption tower 4, the resulting purified hydrogen mixed gas flows out through the purified gas outlet 43, and the remaining mixed tail gas solution (i.e., rich liquid) containing a large amount of carbon dioxide flows out through the tail gas outlet 42 and then flows into the carbon dioxide capture system, where the carbon dioxide is recovered.

[0028] Furthermore, the carbon dioxide capture system includes a carbon dioxide purification unit and a carbon dioxide compression unit. The carbon dioxide purification unit is used to purify the mixed exhaust gas to separate the carbon dioxide from other gases, thereby obtaining high-purity carbon dioxide gas.

[0029] The carbon dioxide purification unit includes a regeneration tower 5, a reboiler 6, a first water cooler 7, and a second gas-liquid separator 8. The regeneration tower 5 is connected to the reboiler 6 so that the reboiler 6 can provide the regeneration tower 5 with continuously boiling liquid to complete the separation of carbon dioxide. The first water cooler 7 is used to cool the purified carbon dioxide gas to separate the liquid substances therein. The second gas-liquid separator 8 is used to separate the liquid contained in the cooled carbon dioxide gas.

[0030] Specifically, the regeneration tower 5 includes a rich liquid inlet 51, a carbon dioxide outlet 52, a circulation inlet 53, and a circulation outlet 54. The rich liquid inlet 51 is used to introduce mixed tail gas; in this embodiment, the rich liquid inlet 51 is connected to the tail gas outlet 42. The carbon dioxide outlet 52 is used to discharge purified carbon dioxide gas. The reboiler 6 includes a heating inlet 61, a heating outlet 62, and a lean liquid outlet 63. The circulation outlet 54 is connected to the heating inlet 61, and the circulation inlet 53 is connected to the heating outlet 62. The lean liquid outlet 63 is connected to the equipment in the next process.

[0031] During operation, the mixed tail gas solution containing a large amount of carbon dioxide, i.e., the rich liquid, flows into the regeneration tower 5 through the rich liquid inlet 51 for carbon dioxide recovery. The recovered carbon dioxide gas flows out through the carbon dioxide outlet 52 and enters the first water cooler 7. After being cooled in the water cooler 7, it flows into the second gas-liquid separator 8 for gas-liquid separation. The resulting liquid flows out through the liquid outlet of the second gas-liquid separator 8, and the remaining cooled carbon dioxide gas enters the carbon dioxide compression unit.

[0032] The carbon dioxide compression unit includes a carbon dioxide compressor 9, which converts carbon dioxide gas into liquid carbon dioxide for easy storage and transportation.

[0033] The above technical solution enables the recovery of carbon dioxide during the methanol-to-hydrogen process. The recovered liquid carbon dioxide can be used in other industrial production, thereby improving energy efficiency. Simultaneously, the use of a multi-stream heat exchanger 1 for heating and heat exchange in this methanol-to-hydrogen system reduces the system's footprint and allows for secondary recovery and utilization of thermal energy from the heat medium and reformed gas mixture, improving the system's thermal efficiency and saving energy.

[0034] Example 2:

[0035] The difference between this embodiment and embodiment 1 is that, Figure 1 As shown, the carbon dioxide purification unit also includes an amine recovery device for recycling the amine solution used in carbon dioxide purification.

[0036] The amine recovery device includes a second water cooler 100 and an amine storage tank 110. The second water cooler 100 is connected to the lean liquid outlet 63 to cool the lean liquid. The second water cooler 100 is also connected to the amine storage tank 110, allowing the lean liquid to flow into the amine storage tank 110 for further cooling and storage. Simultaneously, the absorption tower 4 also includes an amine inlet 44. The amine storage tank 110 includes a lean liquid inlet 111 and an amine outlet 112, with the outlet 112 connected to the inlet 44 to provide organic amine liquid for purification in the absorption tower 4.

[0037] Furthermore, the amine recovery device also includes a first heat exchanger 120 and a transfer pump 130. The first heat exchanger 120 is used to exchange heat between the lean liquid and the rich liquid, so that the heat energy in the lean liquid can be further recovered and utilized. The transfer pump 130 is located between the amine storage tank 110 and the absorption tower 4, so that the organic amine liquid can flow smoothly into the absorption tower 4. The first heat exchanger 120 is located between the absorption tower 4 and the regeneration tower 5, so as to cool the tail gas mixture and simultaneously heat the lean liquid.

[0038] Example 3:

[0039] The difference between this embodiment and embodiment 1 or 2 is that, Figure 1 As shown, the methanol-to-hydrogen system also includes a hydrogen collection device, which comprises an alkylator 200, a second heat exchanger 210, and a third gas-liquid separator 220. The alkylator 200 is used to methanate the purified hydrogen mixture, converting trace amounts of carbon monoxide and carbon dioxide into methane. The second heat exchanger 210 is used to exchange heat between the alkylated mixture and the purified hydrogen mixture to recover and utilize the heat energy in the alkylated mixture. The third gas-liquid separator 220 is used to separate the alkylated mixture into gas and liquid components to ensure the purity of the hydrogen.

[0040] Example 4:

[0041] The difference between this embodiment and embodiments 1, 2, or 3 is that, Figure 2 As shown, the methanol-to-hydrogen unit also includes a heat medium circulation device to recover the residual heat energy in the heat medium flowing out of the multi-stream heat exchanger 1, and to preheat the heat medium that is about to flow into the multi-stream heat exchanger 1.

[0042] The heat medium circulation device includes a cooler 101, a manual valve 102, a flow regulating valve 103, and a third heat exchanger 104. The third heat exchanger 104 is used to exchange heat between the heat medium flowing out of the multi-stream heat exchanger 1 and the heat medium flowing into the multi-stream heat exchanger 1, thereby recovering residual heat energy in the heat medium. Furthermore, the cooler 101 within the heat medium circulation device further recovers or cools the heat energy of the outflowing heat medium, making it recyclable.

[0043] The manual valve 102 and the flow regulating valve 103 are used to control the flow rate of the heat medium in the heat medium circulation device, thereby controlling the amount of heat medium flowing into the multi-stream heat exchanger 1.

[0044] Example 5:

[0045] The difference between this embodiment and any of the embodiments 1 to 4 is that, Figure 3 As shown, the methanol-to-hydrogen unit also includes a methanol-water delivery device, which includes a methanol-water pressurization system and a flow control system connected in sequence.

[0046] The methanol-water pressurization system is used to pressurize methanol-water to meet production requirements. The system includes a ball valve 105, a booster pump 106, and a check valve 107 connected in sequence. The ball valve 105 controls the inflow of methanol-water, the booster pump 106 pressurizes the methanol-water, and the check valve 107 allows the methanol-water to flow out in one direction only.

[0047] The flow control system is used to control the amount of methanol-water flowing into the methanol-to-hydrogen system, and it includes a valve 108 and a control device 109. The control device 109 includes a flow regulating valve 1091 and a flow meter 1092.

[0048] It should be noted that the technical features in embodiments 1 to 5 above can be combined arbitrarily, and the resulting technical solutions all fall within the protection scope of this application. Furthermore, in this document, terms such as "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0049] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A methanol-to-hydrogen system comprising a methanol-to-hydrogen unit, the hydrogen unit comprising a heater and a reforming reactor, characterized in that, The hydrogen production unit further includes a multi-stream heat exchanger, which includes a first inlet, a second inlet, a third inlet, a fourth inlet, a first outlet, a second outlet, a third outlet, and a fourth outlet. A methanol-water mixture is introduced into the first inlet. The first outlet is connected to the material inlet of the reforming reactor. The second inlet is connected to the fourth outlet and the second outlet is connected to the heat medium inlet of the reforming reactor. The third inlet is connected to the reformed mixed gas outlet of the reforming reactor. The fourth inlet is connected to the heat medium outlet of the reforming reactor.

2. The methanol-to-hydrogen system of claim 1, wherein, The methanol-to-hydrogen system further includes a carbon dioxide recovery unit, which includes an absorption tower and a carbon dioxide capture system. The absorption tower includes a mixed gas inlet, a tail gas outlet, and a purified gas outlet. The third outlet flows into the mixed gas inlet. The tail gas outlet is connected to the carbon dioxide capture system.

3. The methanol-to-hydrogen system of claim 2, wherein, The methanol-to-hydrogen unit also includes a condenser and a first gas-liquid separator connected in series, and the third outlet is connected to the mixed gas inlet via the condenser.

4. The methanol-to-hydrogen system of claim 2 or 3, wherein, The carbon dioxide capture system includes a carbon dioxide purification unit and a carbon dioxide compression unit; the carbon dioxide purification unit includes a regeneration tower, a first chiller and a second gas-liquid separator connected in sequence, and a reboiler connected to the regeneration tower.

5. The methanol-to-hydrogen system of claim 4, wherein, The regeneration tower includes a rich liquid inlet, a carbon dioxide outlet, a circulation inlet, and a circulation outlet. The rich liquid inlet is connected to the tail gas outlet. The reboiler includes a heating inlet, a heating outlet, and a lean liquid outlet. The circulation outlet is connected to the heating inlet, and the circulation inlet is connected to the heating outlet.

6. The methanol-to-hydrogen system of claim 5, wherein, The carbon dioxide purification unit also includes an amine recovery device, which includes a second water cooler and an amine storage tank; one end of the second water cooler is connected to the lean liquid outlet, and the other end is connected to the amine storage tank.

7. The methanol-to-hydrogen system of claim 6, wherein, The absorption tower also includes an amine liquid inlet, and the amine liquid tank includes a lean liquid inlet and an amine liquid outlet, with the amine liquid outlet connected to the amine liquid inlet.

8. The methanol-to-hydrogen system of claim 6, wherein, The amine recovery device further includes a first heat exchanger and a transfer pump; the transfer pump is located between the amine storage tank and the absorption tower, and the first heat exchanger is located between the absorption tower and the regeneration tower.

9. The hydrogen production system according to claim 2 or 3, wherein The methanol-to-hydrogen system also includes a hydrogen collection device, which comprises an alkylator and a third gas-liquid separator connected in sequence; the alkylator is connected to the purified gas outlet.

10. The methanol-to-hydrogen system of claim 2 or 3, wherein, The methanol-to-hydrogen unit also includes a heat medium circulation device, which includes a cooler, a flow regulating valve, and a third heat exchanger. The third heat exchanger is used to exchange heat between the heat medium flowing out of the multi-stream heat exchanger and the heat medium flowing into the multi-stream heat exchanger.

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