Hydrogen purification system

Abstract

The utility model discloses a hydrogen purification system. The hydrogen purification system comprises a deoxidation tower, a cooler, a drying tower, a heat exchanger and a gas-water separator, a hydrophilic wire mesh demister (14) is mounted at the upper part of the gas-water separator, and a hydrophobic coating (15) is arranged in a partial region in the gas-water separator. According to the system disclosed by the utility model, the hydrophilic wire mesh demister is additionally arranged at the top of the gas-water separator, and local hydrophobic modification is performed on the inner wall of the gas-water separator, so that the condensation of water drops is promoted, and the gas-water separation efficiency is improved; hydrogen flowing out of the regeneration drying tower is subjected to heat exchange through the heat exchanger, hydrogen entering the deoxidizing tower is preheated, and energy consumption of equipment is reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of inorganic chemical synthesis, and relates to a hydrogen purification system based on a super-hydrophilic A-type molecular sieve, and specifically relates to a kaolin synthetic hydrophilic A-type molecular sieve, a preparation method thereof, and a hydrogen purification system based on the molecular sieve. Background Art

[0002] As the global demand for renewable energy and clean energy continues to increase, hydrogen energy technology has attracted much attention. As a very clean fuel, hydrogen energy is considered a potential solution to global energy and environmental problems. The electrolysis of water to produce hydrogen technology is one of the main technologies for producing hydrogen at present. The electrolysis of water to produce hydrogen technology refers to the process of using electrical energy to decompose water into hydrogen and oxygen. Its advantages are: First, compared with carbon dioxide and other pollutants produced by traditional combustion processes, the electrolysis of water to produce hydrogen only produces water vapor, so it has very low carbon emissions and pollutant emissions. In addition, the electrolysis of water to produce hydrogen technology also has the advantages of high flexibility and fast response time. It can be well integrated with renewable energy to achieve the interconnection of electricity, hydrogen and thermal energy. Second, the electrolysis of water to produce hydrogen technology can help achieve the transformation of clean energy. By using renewable energy to generate electricity and converting electricity into hydrogen, the use of fossil energy and carbon emissions can be greatly reduced, which is conducive to the sustainable development of the energy structure and the mitigation of climate change. Third, the electrolysis of water to produce hydrogen technology can be used for energy storage. Due to the volatility and instability of renewable energy, energy storage technology is needed to balance the difference between energy supply and demand. By converting electrical energy into hydrogen, it can be converted back into electrical energy when needed to meet energy needs.

[0003] The technology of producing hydrogen by electrolysis of water uses electricity to decompose water into hydrogen and oxygen. Due to the interpenetration of hydrogen and oxygen during the production process, there is a trace amount of oxygen in the hydrogen product, resulting in the inability of the hydrogen purity to meet specific industrial needs and applications. The hydrogen purification system generally uses a palladium-based catalyst to remove oxygen, and water is produced as a by-product. In addition, a large amount of water needs to be removed during the hydrogen production process. The hydrogen purification system generally uses type A zeolite molecular sieve as an adsorbent. Type A zeolite molecular sieve is a porous material with inherent microporosity and high thermal stability. It has a highly regular pore structure and adjustable pore size, which can be used to selectively adsorb molecules of different sizes. In the hydrogen purification system, the water molecules and the hydrophilic sites on the surface of the zeolite molecular sieve interact with each other, so that the water molecules are adsorbed by the molecular sieve, thereby achieving the removal of water. At present, the hydrogen purification system still has the following problems: 1. Limited by the hydrophilicity of the molecular sieve, the hydrogen drying efficiency is low. In order to ensure the purity of the hydrogen product, it is generally necessary to increase the volume of the drying tower, resulting in a high cost of hydrogen purification equipment. 2. Chemical reagents are generally used as raw materials for synthesizing zeolite molecular sieves. Chemical reagents are expensive, resulting in a high cost for synthesizing molecular sieves. 3. The gas-water separator itself is hydrophilic, and water droplets easily form a water film on its surface without condensing, resulting in a low separation efficiency. The water carried in the hydrogen passing through the deoxygenation tower and the regeneration tower is not fully removed, which increases the workload of the next adsorption tower and reduces the working life of the adsorption tower. 4. During the deoxygenation of the deoxygenation tower and the regeneration of the drying tower, the hydrogen generally needs to be heated to a certain temperature. In addition, a large amount of cooling water is required to cool the hydrogen when the hydrogen coming out of the drying tower enters the cooler, which will undoubtedly increase the energy consumption of the equipment.

[0004] In order to solve the above problems, the present utility model is proposed. Utility Model Content

[0005] The utility model solves the problems of low drying efficiency, low gas-water separation efficiency and high adsorbent synthesis cost of hydrogen purification equipment. The utility model discloses a hydrogen purification system based on kaolin-synthesized super-hydrophilic A-type molecular sieve, including the following contents: using kaolin-synthesized super-hydrophilic molecular sieve; filling the super-hydrophilic molecular sieve as an adsorbent in the drying tower of hydrogen purification equipment to enhance the adsorption efficiency of the drying tower; locally hydrophobicizing the gas-water separator of the hydrogen purification equipment, and adding a wire mesh demister at the same time, super-hydrophilic treatment of the wire mesh, further removing moisture, and improving its gas-water separation efficiency; using a heat exchanger to heat the hydrogen flowing out of the regeneration drying tower, preheating the hydrogen entering the deoxidation tower, reducing the heating power of the deoxidation tower, reducing the cooling water consumption of the cooler, and reducing the energy consumption of the equipment. The utility model uses a molecular sieve synthesized from kaolin as an adsorbent for a hydrogen purification system, thereby reducing the synthesis cost of the molecular sieve and enhancing the hydrophilicity of the molecular sieve; using a super-hydrophilic A-type molecular sieve as an adsorbent can greatly improve the adsorption efficiency of hydrogen purification equipment and reduce the space of a drying tower; the system installs a wire mesh demister on the top of the gas-water separator, performs super-hydrophilic treatment on the wire mesh demister to ensure that water gathers on the surface of the wire mesh to form water droplets and drips, performs local hydrophobic modification on the inner wall of the gas-water separator, and the overall hydrophilicity and local hydrophilic coating of the gas-water separator ensure that water gathers into water droplets at hydrophobic sites, promotes condensation of water droplets, and improves the gas-water separation efficiency; the heat exchanger exchanges heat between the hydrogen flowing out of the regeneration drying tower and the hydrogen entering the deoxygenation tower, thereby reducing the energy consumption of the equipment; the hydrophilic contact angle of the super-hydrophilic A-type molecular sieve prepared by the utility model is 24-27°.

[0006] The hydrophilic A-type molecular sieve in the utility model refers to a hydrophilically modified A-type molecular sieve.

[0007] The utility model provides a hydrogen purification system, which comprises a deoxidation tower, a cooler, a drying tower and a gas-water separator;

[0008] A hydrophilic wire mesh demister 14 is installed on the upper part of the gas-water separator, and a hydrophobic coating 15 is provided in some areas inside the gas-water separator; the wire mesh of the wire mesh demister 14 needs to be hydrophilic treated, and the method of hydrophilic treatment is: using a plasma plasma treatment instrument to etch the surface of the wire mesh to make the surface of the wire mesh "rough", forming fine pits and grooves, increasing the specific surface area of ​​the wire mesh material, improving the wetting performance of the wire mesh surface, and enhancing the hydrophilic performance.

[0009] The drying tower is filled with kaolin synthetic super-hydrophilic A-type molecular sieve adsorbent;

[0010] The hydrophilic contact angle of the super-hydrophilic A-type molecular sieve is 24-27°; the preparation method of the super-hydrophilic A-type molecular sieve comprises the following steps:

[0011] (1) adding a silicon source and an aluminum source to a sodium hydroxide aqueous solution respectively, mixing and stirring, and aging for a period of time to obtain a molecular sieve seed solution;

[0012] (2) adding kaolin, a silicon source, an aluminum source and the molecular sieve seed solution obtained in step (1) into a sodium hydroxide aqueous solution and aging for a period of time to obtain a molecular sieve gel;

[0013] (3) transferring the molecular sieve gel obtained in step (2) to a reaction vessel for crystallization reaction;

[0014] (4) filtering the reactant obtained in step (3), washing it, and drying the filter cake to obtain 4A molecular sieve;

[0015] (5) subjecting the 4A molecular sieve obtained in step (4) to ion exchange to obtain a hydrophilic type A molecular sieve.

[0016] (6) The super-hydrophilic A-type molecular sieve obtained in step (5) is shaped and calcined into balls, and loaded into hydrogen purification equipment.

[0017] Super hydrophilic molecular sieves can ensure that water molecules can better infiltrate the desiccant, improve adsorption efficiency, reduce the volume of the drying tower, and reduce equipment production costs.

[0018] In the utility model, a hydrophilic wire mesh demister is installed on the top of the gas-water separator, and the wire mesh is subjected to super-hydrophilic treatment. The wettability of the super-hydrophilic wire mesh filaments, the surface tension of the liquid and the capillary action of the filaments make the droplets grow larger and larger until the aggregated droplets are so large that the gravity generated by themselves exceeds the combined force of the rising force of the gas and the surface tension of the liquid. The droplets then separate and fall from the filaments, thereby improving the separation efficiency of the gas-water separator.

[0019] In the utility model, the heat exchanger performs preliminary heat exchange on the hydrogen flowing out of the dryer, and the heat is used to preheat the hydrogen entering the deoxidation tower, thereby reducing the heating power of the deoxidation tower. Moreover, when the hydrogen after the preliminary heat exchange enters the cooler for cooling, the cooling water consumption is greatly reduced, thereby reducing the energy consumption of the equipment.

[0020] In the utility model, the interior of the gas-water separator is locally treated with a hydrophobic coating to promote the formation of water droplets inside the gas-liquid separator and improve the gas-water separation efficiency.

[0021] Preferably, the cooler includes a first cooler 5, a second cooler 6, a third cooler 7, and a fourth cooler 8;

[0022] The drying tower comprises a first drying tower 2, a second drying tower 3, and a third drying tower 4;

[0023] The gas-water separators include a first gas-water separator 9 , a second gas-water separator 10 , a third gas-water separator 11 , a fourth gas-water separator 12 , and a fifth gas-water separator 13 .

[0024] The heat exchanger includes a first heat exchanger 16 and a second heat exchanger 17 .

[0025] Preferably, the hydrogen produced by the hydrogen production equipment is converted into product hydrogen, and the hydrogen purification system has three hydrogen purification routes, wherein the first hydrogen purification route is:

[0026] The hydrogen produced from the hydrogen production equipment passes through the first gas-water separator 9 to remove part of the water carried by the hydrogen, and then enters the second heat exchanger 17 for preheating. The hydrogen coming out of the second heat exchanger 17 then enters the deoxidation tower 1, where oxygen participates in the reaction and is converted into water. The gas coming out of the deoxidation tower 1 passes through the first cooler 5 for cooling, and then enters the second gas-water separator 10 for gas-water separation to remove water.

[0027] The hydrogen coming out from the upper end of the second gas-water separator 10 enters the fourth gas-water separator 12 and the third cooler 7 through the second three-way valve 202, and then enters the second drying tower 3 through the eighth three-way valve 208 for drying;

[0028] The gas flowing out of the second drying tower 3 is produced as product hydrogen after passing through the fifth three-way valve 205 and the needle valve 213, and the remaining part passes through the sixth three-way valve 206 to enter the third drying tower 4 for drying tower regeneration. The gas coming out of the third drying tower 4 passes through the ninth three-way valve 209 to enter the first heat exchanger 16 for heat exchange of hydrogen, and then passes through the third magnetic valve 212 to enter the fourth cooler 8 and the fifth gas-water separator 13 to remove part of the water generated by the third drying tower 4;

[0029] The gas flowing out of the fifth gas-water separator 13 enters the third gas-water separator 11 and the second cooler 6 through the third three-way valve 203 and the first three-way valve 201, then enters the first drying tower 2 for drying through the seventh three-way valve 207, and finally flows into the product hydrogen main circuit through the fourth three-way valve 204.

[0030] The third drying tower 4 in this route is a regeneration drying tower.

[0031] The second hydrogen purification route of the hydrogen purification system is:

[0032] The hydrogen produced from the hydrogen production equipment passes through the first gas-water separator 9 to remove part of the water carried by the hydrogen, and then enters the second heat exchanger 17 for preheating. The hydrogen coming out of the second heat exchanger 17 enters the deoxidation tower 1, where oxygen participates in the reaction and is converted into water. The gas coming out of the deoxidation tower 1 passes through the first cooler 5 for cooling, and then enters the second gas-water separator 10 for gas-water separation to remove water.

[0033] The hydrogen coming out from the upper end of the second gas-water separator 10 passes through the three-way valve 201 and enters the third gas-water separator 11 and the second cooler 6, and then passes through the seventh three-way valve 207 and enters the first drying tower 2 for drying;

[0034] Part of the gas flowing out of the first drying tower 2 passes through the fourth three-way valve 204 and the needle valve 213 to be produced as product hydrogen, and the remaining part passes through the fifth three-way valve 205 to enter the second drying tower 3 for drying tower regeneration. The gas coming out of the second drying tower 3 passes through the eighth three-way valve 208 to enter the first heat exchanger 16 for heat exchange of hydrogen, and then passes through the second magnetic valve 211 to enter the third cooler 7 and the fourth gas-water separator 12 to remove part of the water generated by the second drying tower 3;

[0035] The gas flowing out of the fourth gas-water separator 12 enters the fifth gas-water separator 13 and the fourth cooler 8 through the second three-way valve 202 and the third three-way valve 203, then enters the third drying tower 4 through the ninth three-way valve 209 for drying, and finally flows into the product hydrogen main circuit through the sixth three-way valve 206.

[0036] The second drying tower 3 in this route is a regeneration drying tower.

[0037] The third hydrogen purification route of the hydrogen purification system is:

[0038] The hydrogen produced from the hydrogen production equipment passes through the first gas-water separator 9 to remove part of the water carried by the hydrogen, and then enters the second heat exchanger 17 for preheating. The hydrogen coming out of the second heat exchanger 17 then enters the deoxidation tower 1, where oxygen participates in the reaction and is converted into water. The gas coming out of the deoxidation tower 1 passes through the first cooler 5 for cooling, and then enters the second gas-water separator 10 for gas-water separation to remove water.

[0039] The hydrogen coming out from the upper end of the second gas-water separator 10 passes through the third three-way valve 203 and enters the fifth gas-water separator 13 and the fourth cooler 8, and then passes through the ninth three-way valve 209 and enters the third drying tower 4 for drying;

[0040] Part of the gas flowing out of the third drying tower 4 passes through the sixth three-way valve 206 and the needle valve 213 to be produced as product hydrogen, and the remaining part passes through the fourth three-way valve 204 to enter the first drying tower 2 for drying tower regeneration. The gas coming out of the first drying tower 2 passes through the seventh three-way valve 207 to enter the first heat exchanger 16 for heat exchange of hydrogen, and then passes through the first magnetic valve 210 to enter the second cooler 6 and the third gas-water separator 11 to remove part of the water generated by the first drying tower 2;

[0041] The gas flowing out of the third gas-water separator 11 enters the fourth gas-water separator 12 and the third cooler 7 through the first three-way valve 201 and the second three-way valve 202, then enters the second drying tower 3 through the eighth three-way valve 208 for drying, and finally flows into the product hydrogen main circuit through the fifth three-way valve 205.

[0042] In this route, the first drying tower 2 is a regeneration drying tower.

[0043] Preferably, step (1) is to prepare two sodium hydroxide solutions of a certain concentration, add sodium silicate and sodium aluminate respectively, mix the two after they are completely dissolved, stir evenly, and age at room temperature for a period of time to obtain a molecular sieve seed solution, wherein the molecular sieve seed solution has a ratio of sodium silicate: sodium aluminate: sodium hydroxide: water of 7-10:2-3:1:18-20, the stirring time is 8-24h, and the stirring temperature is 25°C.

[0044] Preferably, step (2) is to prepare a sodium hydroxide solution of a certain concentration, add sodium aluminate or sodium silicate, kaolin and the molecular sieve seed solution obtained in step (1), stir and age for a period of time at room temperature to obtain a molecular sieve gel, wherein the molecular sieve gel has a ratio of kaolin: sodium silicate: sodium aluminate: sodium hydroxide: molecular sieve seed: water of 25-30:0-2:0-1.4:30-40:30:300-310, the stirring time is 2-8h, and the stirring temperature is room temperature. In other words, the amount of sodium aluminate added can be 0, while sodium silicate is added; or the amount of sodium silicate added can be 0, while sodium aluminate is added.

[0045] Preferably, in step (3), the crystallization temperature is 80-130° C., and the crystallization time is 3-24 h.

[0046] Preferably, in step (4), the filter cake is washed to a pH of 8 to 10, the drying temperature is 80 to 120° C., and the drying time is 4 to 24 hours.

[0047] Preferably, in step (5), the ion exchange includes direct ion exchange and indirect ion exchange. The direct ion exchange uses a mixture of one or more solutions of zinc chloride, calcium chloride, and magnesium chloride to exchange ions with the 4A molecular sieve. The indirect ion exchange uses an ammonium chloride solution to exchange ions. After the exchange, a secondary ion exchange is performed using nitrate, followed by washing, drying, and high-temperature calcination to obtain a hydrophilic modified molecular sieve.

[0048] More preferably, direct ion exchange is to use 1 mol / L zinc chloride, calcium chloride, magnesium chloride or a mixture of one or more solutions thereof to carry out ion exchange with 4A molecular sieve, the ion exchange temperature is 80-100° C., and the ion exchange time is 6-8 h.

[0049] More preferably, the indirect ion exchange is to use 1 mol / L ammonium chloride solution for ion exchange three times, and after the exchange, use 0.1-0.5 mol / L nitrate for secondary ion exchange, wash, dry, and high-temperature calcination to obtain the hydrophilic modified molecular sieve. The ion exchange temperature is 40-60°C, the ion exchange time is 2-4h, the muffle furnace calcination temperature is 300-500°C, and the calcination time is 2-4h.

[0050] Preferably, in step (6), the calcination temperature of the super-hydrophilic A-type molecules used in the hydrogen purification equipment is 300-500° C. and the calcination time is 6-12 h.

[0051] Compared with the prior art, the utility model has the following beneficial effects:

[0052] 1. The chemical formula of kaolin is Al4[Si4O 10 ](OH)8, the main chemical components are silicon oxide and aluminum oxide, and also contain trace elements such as titanium, iron, and zirconium. The utility model takes a different approach by using kaolin as the silicon source and aluminum source for synthesizing zeolite molecular sieves. The trace elements such as titanium, iron, and zirconium in kaolin enter the molecular sieve pores during the hydrothermal process, greatly improving the hydrophilicity of the A-type molecular sieve. Furthermore, the utility model can enhance the hydrophilicity of the molecular sieve by introducing new cations through ion exchange.

[0053] 2. The utility model uses a super-hydrophilic A-type molecular sieve synthesized from kaolin as an adsorbent filled in the drying tower of the hydrogen purification equipment. The super-hydrophilic molecular sieve can cause water molecules to be quickly separated from hydrogen, thereby improving the adsorption efficiency of the drying tower. In addition, as the adsorption efficiency is improved, the volume of the drying tower can also be reduced, the equipment space becomes smaller, and the cost is reduced. The super-hydrophilic molecular sieve can ensure that water molecules better infiltrate the desiccant, improve the adsorption efficiency, reduce the volume of the drying tower, and reduce the production cost of the equipment.

[0054] 3. The utility model gas-water separator is equipped with a hydrophilic wire mesh demister and a local hydrophobic coating, and the wire mesh demister is subjected to super-hydrophilic treatment. When hydrogen rises at a certain speed through the super-hydrophilic wire mesh, due to the inertia of the rising mist, the mist collides with the super-hydrophilic wire mesh filaments and is attached to the surface of the filaments. The diffusion of the mist on the surface of the super-hydrophilic filaments and the gravity sedimentation of the mist cause the mist to form larger droplets that flow along the filaments to the junction of the two filaments, and then separate and fall from the filaments. The hydrophobic coating of the gas-water separator can destroy the water film formed on the inner wall of the metal due to its hydrophilicity. Water nucleates at the hydrophobic point and gradually grows into water droplets that flow out from the lower end of the gas-water separator.

[0055] 4. The utility model installs a heat exchanger between the dryer and the cooler and before the deoxidation tower, and uses the heat of the hydrogen flowing out of the regeneration drying tower to preheat the hydrogen entering the deoxidation tower, thereby reducing the heating power of the deoxidation tower; at the same time, since the regeneration drying tower undergoes preliminary heat exchange through the heat exchanger, the temperature of the hydrogen is reduced, the load of the subsequent cooler is greatly reduced, and the energy consumption of the equipment is reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0056] Figure 1 is the XRD diagram of the type A molecular sieve obtained in Example 1, from which the characteristic peaks of the standard type A molecular sieve can be observed;

[0057] Figure 2 : is a SEM image of the type A molecular sieve obtained in Example 1, from which it can be observed that the type A molecular sieve has a uniform morphology and a uniform particle size;

[0058] Figure 3 : is a contact angle diagram of a water drop on the surface of a commercial type A molecular sieve and the type A molecular sieve obtained in Example 1, wherein the contact angle of the commercial type A molecular sieve is 37.5°, while the contact angle of the type A molecular sieve obtained in Example 1 is 24°;

[0059] Figure 4 This is the equipment design diagram of the type A molecular sieve obtained in Example 1 applied to the hydrogen purification system;

[0060] Figure 5 This is the first hydrogen purification route of the utility model;

[0061] Figure 6 This is the second hydrogen purification route of the utility model;

[0062] Figure 7 This is the third hydrogen purification route of the utility model;

[0063] Figure 8 This is the filling method of the super-hydrophilic molecular sieve in the drying tower of the utility model embodiment;

[0064] Fig. 9 It is a structural schematic diagram of the gas-water separator provided in an embodiment of the utility model and a partial enlarged diagram of its hydrophobic coating.

[0065] Reference numerals:

[0066] 1. Deoxygenation tower; 2. First drying tower; 3. Second drying tower; 4. Third drying tower; 5. First cooler; 6. Second cooler; 7. Third cooler; 8. Fourth cooler; 9. First gas-water separator; 10. Second gas-water separator; 11. Third gas-water separator; 12. Fourth gas-water separator; 13. Fifth gas-water separator; 14. Wire mesh demister; 15. Hydrophobic coating; 16. First heat exchanger; 17. Second heat exchanger; 201. First three-way valve; 202. Second three-way valve; 203. Third three-way valve; 204. Fourth three-way valve; 205. Fifth three-way valve; 206. Sixth three-way valve; 207. Seventh three-way valve; 208. Eighth three-way valve; 209. Ninth three-way valve; 210. First magnetic valve; 211. Second magnetic valve; 212. Third magnetic valve; 213. Needle valve. DETAILED DESCRIPTION

[0067] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only a part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0068] The hydrogen purification system used in this embodiment includes a deoxygenation tower, a cooler, a drying tower and a gas-water separator;

[0069] A hydrophilic wire mesh demister 14 is installed on the upper part of the gas-water separator, and a hydrophobic coating 15 is provided in some areas inside the gas-water separator; the wire mesh of the wire mesh demister 14 needs to be hydrophilic treated, and the method of hydrophilic treatment is: using a plasma plasma treatment instrument to etch the surface of the wire mesh to make the surface of the wire mesh "rough", forming fine pits and grooves, increasing the specific surface area of ​​the wire mesh material, improving the wetting performance of the wire mesh surface, and enhancing the hydrophilic performance.

[0070] The drying tower is filled with kaolin synthetic super-hydrophilic A-type molecular sieve adsorbent;

[0071] In the utility model, a hydrophilic wire mesh demister is installed on the top of the gas-water separator, and the wire mesh is subjected to super-hydrophilic treatment. The wettability of the super-hydrophilic wire mesh filaments, the surface tension of the liquid and the capillary action of the filaments make the droplets grow larger and larger until the aggregated droplets are so large that the gravity generated by themselves exceeds the combined force of the rising force of the gas and the surface tension of the liquid. The droplets then separate and fall from the filaments, thereby improving the separation efficiency of the gas-water separator.

[0072] In the utility model, the heat exchanger performs preliminary heat exchange on the hydrogen flowing out of the dryer, and the heat is used to preheat the hydrogen entering the deoxidation tower, thereby reducing the heating power of the deoxidation tower. Moreover, when the hydrogen after the preliminary heat exchange enters the cooler for cooling, the cooling water consumption is greatly reduced, thereby reducing the energy consumption of the equipment.

[0073] In the utility model, the interior of the gas-water separator is locally treated with a hydrophobic coating to promote the formation of water droplets inside the gas-liquid separator and improve the gas-water separation efficiency.

[0074] like Figure 4-9 , the cooler includes a first cooler 5, a second cooler 6, a third cooler 7, and a fourth cooler 8;

[0075] The drying tower comprises a first drying tower 2, a second drying tower 3, and a third drying tower 4;

[0076] The gas-water separators include a first gas-water separator 9 , a second gas-water separator 10 , a third gas-water separator 11 , a fourth gas-water separator 12 , and a fifth gas-water separator 13 .

[0077] The heat exchanger includes a first heat exchanger 16 and a second heat exchanger 17 .

[0078] like Figure 5 , the first hydrogen purification route is:

[0079] The hydrogen produced from the hydrogen production equipment passes through the first gas-water separator 9 to remove part of the water carried by the hydrogen, and then enters the second heat exchanger 17 for preheating. The hydrogen coming out of the second heat exchanger 17 enters the deoxidation tower 1, where oxygen participates in the reaction and is converted into water. The gas coming out of the deoxidation tower 1 passes through the first cooler 5 for cooling, and then enters the second gas-water separator 10 for gas-water separation to remove water.

[0080] The hydrogen coming out from the upper end of the second gas-water separator 10 enters the fourth gas-water separator 12 and the third cooler 7 through the second three-way valve 202, and then enters the second drying tower 3 through the eighth three-way valve 208 for drying;

[0081] The gas flowing out of the second drying tower 3 is produced as product hydrogen after passing through the fifth three-way valve 205 and the needle valve 213, and the remaining part passes through the sixth three-way valve 206 to enter the third drying tower 4 for drying tower regeneration. The gas coming out of the third drying tower 4 passes through the ninth three-way valve 209 to enter the first heat exchanger 16 for heat exchange of hydrogen, and then passes through the third magnetic valve 212 to enter the fourth cooler 8 and the fifth gas-water separator 13 to remove part of the water generated by the third drying tower 4;

[0082] The gas flowing out of the fifth gas-water separator 13 enters the third gas-water separator 11 and the second cooler 6 through the third three-way valve 203 and the first three-way valve 201, then enters the first drying tower 2 for drying through the seventh three-way valve 207, and finally flows into the product hydrogen main path through the fourth three-way valve 204. The third drying tower 4 in the first hydrogen purification route is a regeneration drying tower.

[0083] like Figure 6 , the second hydrogen purification route is:

[0084] The hydrogen produced from the hydrogen production equipment passes through the first gas-water separator 9 to remove part of the water carried by the hydrogen, and then enters the second heat exchanger 17 for preheating. The hydrogen coming out of the second heat exchanger 17 enters the deoxidation tower 1, where oxygen participates in the reaction and is converted into water. The gas coming out of the deoxidation tower 1 passes through the first cooler 5 for cooling, and then enters the second gas-water separator 10 for gas-water separation to remove water.

[0085] The hydrogen coming out from the upper end of the second gas-water separator 10 passes through the three-way valve 201 and enters the third gas-water separator 11 and the second cooler 6, and then passes through the seventh three-way valve 207 and enters the first drying tower 2 for drying;

[0086] Part of the gas flowing out of the first drying tower 2 passes through the fourth three-way valve 204 and the needle valve 213 to be produced as product hydrogen, and the remaining part passes through the fifth three-way valve 205 to enter the second drying tower 3 for drying tower regeneration. The gas coming out of the second drying tower 3 passes through the eighth three-way valve 208 to enter the first heat exchanger 16 for heat exchange of hydrogen, and then passes through the second magnetic valve 211 to enter the third cooler 7 and the fourth gas-water separator 12 to remove part of the water generated by the second drying tower 3;

[0087] The gas flowing out of the fourth gas-water separator 12 enters the fifth gas-water separator 13 and the fourth cooler 8 through the second three-way valve 202 and the third three-way valve 203, then enters the third drying tower 4 through the ninth three-way valve 209 for drying, and finally flows into the product hydrogen main path through the sixth three-way valve 206. The second drying tower 3 in the second hydrogen purification route is a regeneration drying tower.

[0088] like Figure 7 , the third hydrogen purification route is:

[0089] The hydrogen produced from the hydrogen production equipment passes through the first gas-water separator 9 to remove part of the water carried by the hydrogen, and then enters the second heat exchanger 17 for preheating. The hydrogen coming out of the second heat exchanger 17 enters the deoxidation tower 1, where oxygen participates in the reaction and is converted into water. The gas coming out of the deoxidation tower 1 passes through the first cooler 5 for cooling, and then enters the second gas-water separator 10 for gas-water separation to remove water.

[0090] The hydrogen coming out from the upper end of the second gas-water separator 10 passes through the third three-way valve 203 and enters the fifth gas-water separator 13 and the fourth cooler 8, and then passes through the ninth three-way valve 209 and enters the third drying tower 4 for drying;

[0091] Part of the gas flowing out of the third drying tower 4 passes through the sixth three-way valve 206 and the needle valve 213 to be produced as product hydrogen, and the remaining part passes through the fourth three-way valve 204 to enter the first drying tower 2 for drying tower regeneration. The gas coming out of the first drying tower 2 passes through the seventh three-way valve 207 to enter the first heat exchanger 16 for heat exchange of hydrogen, and then passes through the first magnetic valve 210 to enter the second cooler 6 and the third gas-water separator 11 to remove part of the water generated by the first drying tower 2;

[0092] The gas flowing out of the third gas-water separator 11 enters the fourth gas-water separator 12 and the third cooler 7 through the first three-way valve 201 and the second three-way valve 202, then enters the second drying tower 3 through the eighth three-way valve 208 for drying, and finally enters the product hydrogen main path through the fifth three-way valve 205. The first drying tower 2 in the third hydrogen purification route is a regeneration drying tower.

[0093] Example 1

[0094] (1) Add 2 g of sodium hydroxide to two 20 mL aqueous solutions, and after the solution is completely dissolved, add 12 g of sodium silicate and 3 g of sodium aluminate respectively. After the sodium silicate and sodium aluminate are completely dissolved, add the sodium aluminate solution dropwise to the sodium silicate solution, and stir at room temperature for 8 h to obtain a molecular sieve seed solution;

[0095] (2) Add 4.4 g of sodium hydroxide to 40 mL of aqueous solution, add 0.2 g of sodium aluminate after the sodium hydroxide is completely dissolved, add 4 g of kaolin and 4 mL of seed solution after the sodium aluminate is dissolved, and stir at room temperature for 2 h to obtain a molecular sieve gel;

[0096] (3) transferring the molecular sieve gel obtained in step (2) to a reactor for crystallization reaction at 100° C. for 8 h;

[0097] (4) The liquid after the reaction obtained in step (3) was filtered and washed with deionized water for multiple times until the pH value was 9, and the filter cake was dried to obtain 4A molecular sieve;

[0098] (5) Add 4A molecular sieve to 1 mol / L calcium chloride solution, perform ion exchange at 90°C for 4 h, filter the solution after ion exchange, and dry overnight to obtain a hydrophilic modified molecular sieve

[0099] (6) The modified hydrophilic molecular sieve is shaped into balls, calcined at 500°C for 6 hours, and filled into a drying tower of hydrogen purification equipment. The filling of the super hydrophilic molecular sieve improves the dehydration efficiency of the drying tower and reduces the volume of the hydrogen purification equipment.

[0100] (7) Figure 5 As shown, the gas-water separators are respectively installed at the front end of the deoxidation tower, cooler 5, cooler 6, cooler 7, and cooler 8 rear ends. The gas-water separator 9 at the front end of the deoxidation tower 1 is used to remove moisture carried in the crude hydrogen and reduce the load of the deoxidation tower heater; the gas-water separator 10 is used to remove moisture generated in the deoxidation tower, reduce the water absorption load of the next adsorption tower, and increase its adsorption cycle; the gas-water separators 11, 12, and 13 are respectively used to remove moisture carried in the hydrogen during the regeneration of the drying tower 2, the drying tower 3, and the drying tower 4.

[0101] (8) Figure 5 As shown, a heat exchanger is installed at the front end of the deoxidation tower 1, between the drying tower and the cooler, to perform preliminary heat exchange on the hydrogen flowing out of the regeneration drying tower, which is used to preheat the hydrogen entering the deoxidation tower and reduce the heating power of the deoxidation tower. The temperature of the hydrogen after the preliminary heat exchange is reduced, and when it enters the cooler for heat exchange, the amount of cooling water used is greatly reduced, and the energy consumption of the equipment is reduced.

[0102] (9) Figure 8 As shown, a hydrophilic wire mesh demister is installed on the top of the gas-water separator. The wire mesh demister is treated with super hydrophilicity. The wettability of the super hydrophilic filaments, the surface tension of the liquid and the capillary action of the filaments make the droplets grow larger and larger until the aggregated droplets are so large that the gravity generated by themselves exceeds the combined force of the rising force of the gas and the surface tension of the liquid, and the droplets are separated from the filaments and fall.

[0103] (10) Fig. 9 As shown, local hydrophobic modification is performed inside the gas-water separator. The local hydrophobic sites can destroy the water film formed due to the hydrophilicity of the metal, promote the nucleation and growth of water at the hydrophobic sites, improve the gas-water separation efficiency, reduce the workload of the next working tower, and increase the service life of the equipment.

[0104] Example 2

[0105] (1) Add 2 g of sodium hydroxide to two 20 mL aqueous solutions, and after the solution is completely dissolved, add 12 g of sodium silicate and 3 g of sodium aluminate respectively. After the sodium silicate and sodium aluminate are completely dissolved, add the sodium aluminate solution dropwise to the sodium silicate solution, and stir at room temperature for 8 h to obtain a molecular sieve seed solution;

[0106] (2) Add 4.4 g of sodium hydroxide to 40 mL of aqueous solution, add 0.2 g of sodium aluminate after the sodium hydroxide is completely dissolved, add 4 g of kaolin and 4 mL of seed solution after the sodium aluminate is dissolved, and stir at room temperature for 2 h to obtain a molecular sieve gel;

[0107] (3) transferring the molecular sieve gel obtained in step (2) to a reactor for crystallization reaction at 100° C. for 8 h;

[0108] (4) The liquid after the reaction obtained in step (3) was filtered and washed with deionized water for multiple times until the pH value was 9, and the filter cake was dried to obtain 4A molecular sieve;

[0109] (5) Add 4A molecular sieve to 1 mol / L magnesium chloride solution, perform ion exchange at 90° C. for 4 h, and after the ion exchange, filter the solution and dry overnight to obtain a hydrophilic modified molecular sieve.

[0110] (6) The modified hydrophilic molecular sieve is shaped into balls, calcined at 500° C. for 6 h, and filled into a drying tower of a hydrogen purification equipment.

[0111] Example 3

[0112] (1) Add 2 g of sodium hydroxide to two 20 mL aqueous solutions, and after the solution is completely dissolved, add 12 g of sodium silicate and 3 g of sodium aluminate respectively. After the sodium silicate and sodium aluminate are completely dissolved, add the sodium aluminate solution dropwise to the sodium silicate solution, and stir at room temperature for 8 h to obtain a molecular sieve seed solution;

[0113] (2) Add 4.4 g of sodium hydroxide to 40 mL of aqueous solution, add 0.2 g of sodium aluminate after the sodium hydroxide is completely dissolved, add 4 g of kaolin and 4 mL of seed solution after the sodium aluminate is dissolved, and stir at room temperature for 2 h to obtain a molecular sieve gel;

[0114] (3) transferring the molecular sieve gel obtained in step (2) to a reactor for crystallization reaction at 100° C. for 8 h;

[0115] (4) The liquid after the reaction obtained in step (3) was filtered and washed with deionized water for multiple times until the pH value was 9, and the filter cake was dried to obtain 4A molecular sieve;

[0116] (5) Add 4A molecular sieve to 1 mol / L zinc chloride solution, perform ion exchange at 90° C. for 4 h, and after the ion exchange, filter the solution and dry overnight to obtain a hydrophilic modified molecular sieve.

[0117] (6) The modified hydrophilic molecular sieve is shaped into balls, calcined at 300° C. for 12 h, and filled into a drying tower of a hydrogen purification equipment.

[0118] Example 4

[0119] (1) Add 2 g of sodium hydroxide to two 20 mL aqueous solutions, and after the solution is completely dissolved, add 12 g of sodium silicate and 3 g of sodium aluminate respectively. After the sodium silicate and sodium aluminate are completely dissolved, add the sodium aluminate solution dropwise to the sodium silicate solution, and stir at room temperature for 8 h to obtain a molecular sieve seed solution;

[0120] (2) Add 4.4 g of sodium hydroxide to 40 mL of aqueous solution, add 0.5 g of sodium silicate after the sodium hydroxide is completely dissolved, add 4 g of kaolin and 4 mL of seed solution after the sodium silicate is dissolved, and stir at room temperature for 2 h to obtain a molecular sieve gel;

[0121] (3) transferring the molecular sieve gel obtained in step (2) to a reactor for crystallization reaction at 100° C. for 8 h;

[0122] (4) The liquid after the reaction obtained in step (3) was filtered and washed with deionized water for multiple times until the pH value was 9, and the filter cake was dried to obtain 4A molecular sieve;

[0123] (5) Add 4A molecular sieve to 1 mol / L calcium chloride solution, perform ion exchange at 90° C. for 4 h, and after the ion exchange, filter the solution and dry overnight to obtain a hydrophilic modified molecular sieve.

[0124] (6) The modified hydrophilic molecular sieve is shaped into balls, calcined at 400° C. for 9 h, and filled into a drying tower of a hydrogen purification equipment.

[0125] Example 5

[0126] (1) Add 2 g of sodium hydroxide to two 20 mL aqueous solutions, and after the solution is completely dissolved, add 12 g of sodium silicate and 3 g of sodium aluminate respectively. After the sodium silicate and sodium aluminate are completely dissolved, add the sodium aluminate solution dropwise to the sodium silicate solution, and stir at room temperature for 8 h to obtain a molecular sieve seed solution;

[0127] (2) Add 4.4 g of sodium hydroxide to 40 mL of aqueous solution, add 0.4 g of sodium aluminate after the sodium hydroxide is completely dissolved, add 3.5 g of kaolin and 4 mL of seed solution after the sodium aluminate is dissolved, and stir at room temperature for 2 h to obtain a molecular sieve gel;

[0128] (3) transferring the molecular sieve gel obtained in step (2) to a reactor for crystallization reaction at 100° C. for 8 h;

[0129] (4) The liquid after the reaction obtained in step (3) was filtered and washed with deionized water for multiple times until the pH value was 9, and the filter cake was dried to obtain 4A molecular sieve;

[0130] (5) Add 4A molecular sieve to 1 mol / L ammonium chloride solution, carry out ion exchange at 90° C. for 4 h, perform ion exchange three times, and after the ion exchange is completed, filter the solution and dry it.

[0131] (6) The molecular sieve obtained by ion exchange with ammonium chloride solution was ion exchanged in 0.1 mol / L zirconium nitrate solution at 40° C. for 4 h. The solution was filtered and then calcined in a muffle furnace at 500° C. for 2 h to obtain a hydrophilic modified molecular sieve.

[0132] (7) The modified hydrophilic molecular sieve is shaped into balls, calcined at 400° C. for 6 h, and filled into a drying tower of a hydrogen purification equipment.

[0133] The XRF results of kaolin are shown in Table 1, from which the contents of components in kaolin can be obtained.

[0134] Table 1 XRF results of kaolin

[0135] <![CDATA[SiO2]]> <![CDATA[Al2O3]]> <![CDATA[TiO2]]> <![CDATA[Fe2O3]]> <![CDATA[ZrO2]]> <![CDATA[K2O]]> 50.4300％ 40.3809％ 5.1783％ 2.5364％ 0.7238％ 0.1689％ SrO CaO <![CDATA[P2O5]]> <![CDATA[Ga2O3]]> NbO ZnO 0.2262％ 0.1352％ 0.0589％ 0.0596％ 0.0389％ 0.0341％

[0136] The contact angle data of water droplets on the surface of the hydrophilic modified molecular sieves synthesized in different embodiments are shown in Table 2 below.

[0137] Table 2 Contact angle data of water droplets on the surface of synthetic molecular sieves in different embodiments

[0138] Example 1 Example 2 Example 3 Example 4 Example 5 Commercial Molecular Sieve Contact angle 24° 26° 25° 27° 25° 37.5°

[0139] Through the data in Table 2, combined with Figure 4 It can be found that the preparation method of the present invention can greatly improve the hydrophilicity of type A molecular sieve. The hydrophilic type A molecular sieve prepared by the present invention has a hydrophilic contact angle of 24-27°, wherein the contact angle of commercial type A molecular sieve is 37.5°, while the contact angle of type A molecular sieve obtained in Example 1 is 24°.

Claims

1. A hydrogen purification system, characterized in that: The hydrogen purification system includes a deoxygenation tower, a cooler, a heat exchanger, a drying tower and a gas-water separator; A hydrophilic wire mesh demister (14) is installed on the upper part of the gas-water separator, and a hydrophobic coating (15) is provided in a partial area inside the gas-water separator; The heat exchanger performs heat exchange between the hydrogen flowing out of the drying tower and the hydrogen entering the deoxidation tower.

2. The hydrogen purification system according to claim 1, characterized in that: The drying tower is filled with a super-hydrophilic A-type molecular sieve adsorbent; The hydrophilic contact angle of the super-hydrophilic A-type molecular sieve is 24-27°.

3. The hydrogen purification system according to claim 1, characterized in that: The cooler comprises a first cooler (5), a second cooler (6), a third cooler (7), and a fourth cooler (8); The drying tower comprises a first drying tower (2), a second drying tower (3), and a third drying tower (4); The gas-water separator comprises a first gas-water separator (9), a second gas-water separator (10), a third gas-water separator (11), a fourth gas-water separator (12), and a fifth gas-water separator (13). The heat exchanger comprises a first heat exchanger (16) and a second heat exchanger (17).

4. The hydrogen purification system according to claim 3, characterized in that: The hydrogen purification route of the hydrogen purification system is: The hydrogen produced from the hydrogen production equipment passes through the first gas-water separator (9) to remove part of the water carried by the hydrogen, and then enters the second heat exchanger (17) for preheating. The hydrogen coming out of the second heat exchanger (17) enters the deoxidation tower (1), and oxygen participates in the reaction in the deoxidation tower (1) to be converted into water. The gas coming out of the deoxidation tower (1) passes through the first cooler (5) for cooling, and then enters the second gas-water separator (10) for gas-water separation to remove water. The hydrogen coming out from the upper end of the second gas-water separator (10) passes through the second three-way valve (202) into the fourth gas-water separator (12), the third cooler (7), and then passes through the eighth three-way valve (208) into the second drying tower (3) for drying; Part of the gas flowing out of the second drying tower (3) passes through the fifth three-way valve (205) and the needle valve (213) to be produced as product hydrogen, and the remaining part passes through the sixth three-way valve (206) to enter the third drying tower (4) for drying tower regeneration. The gas coming out of the third drying tower (4) passes through the ninth three-way valve (209) to enter the first heat exchanger (16) to exchange heat with hydrogen, and then passes through the third magnetic valve (212) to enter the fourth cooler (8) and the fifth gas-water separator (13) to remove part of the water generated by the third drying tower (4); The gas flowing out of the fifth gas-water separator (13) passes through the third three-way valve (203) and the first three-way valve (201) to enter the third gas-water separator (11) and the second cooler (6), then passes through the seventh three-way valve (207) to enter the first drying tower (2) for drying, and finally passes through the fourth three-way valve (204) to flow into the main product hydrogen path.

5. The hydrogen purification system according to claim 3, characterized in that: The hydrogen purification route of the hydrogen purification system is: The hydrogen produced from the hydrogen production equipment passes through the first gas-water separator (9) to remove part of the water carried by the hydrogen, and then enters the second heat exchanger (17) for preheating. The hydrogen coming out of the second heat exchanger (17) then enters the deoxidation tower (1), where oxygen participates in the reaction and is converted into water. The gas coming out of the deoxidation tower (1) passes through the first cooler (5) for cooling, and then enters the second gas-water separator (10) for gas-water separation to remove water. The hydrogen coming out from the upper end of the second gas-water separator (10) passes through the first three-way valve (201) into the third gas-water separator (11), the second cooler (6), and then passes through the seventh three-way valve (207) and enters the first drying tower (2) for drying; Part of the gas flowing out of the first drying tower (2) passes through the fourth three-way valve (204) and the needle valve (213) to be produced as product hydrogen, and the remaining part passes through the fifth three-way valve (205) to enter the second drying tower (3) for drying tower regeneration. The gas coming out of the second drying tower (3) passes through the eighth three-way valve (208) to enter the first heat exchanger (16) to exchange heat with hydrogen, and then passes through the second magnetic valve (211) to enter the third cooler (7) and the fourth gas-water separator (12) to remove part of the water generated by the second drying tower (3); The gas flowing out of the fourth gas-water separator (12) enters the fifth gas-water separator (13) and the fourth cooler (8) through the second three-way valve (202) and the third three-way valve (203), then enters the third drying tower (4) for drying through the ninth three-way valve (209), and finally flows into the main product hydrogen path through the sixth three-way valve (206).

6. The hydrogen purification system according to claim 3, characterized in that: The hydrogen purification route of the hydrogen purification system is: The hydrogen produced from the hydrogen production equipment passes through the first gas-water separator (9) to remove part of the water carried by the hydrogen, and then enters the second heat exchanger (17) for preheating. The hydrogen coming out of the second heat exchanger (17) then enters the deoxidation tower (1), where oxygen participates in the reaction and is converted into water. The gas coming out of the deoxidation tower (1) passes through the first cooler (5) for cooling, and then enters the second gas-water separator (10) for gas-water separation to remove water. The hydrogen coming out from the upper end of the second gas-water separator (10) passes through the third three-way valve (203) and enters the fifth gas-water separator (13), the fourth cooler (8), and then passes through the ninth three-way valve (209) and enters the third drying tower (4) for drying; Part of the gas flowing out of the third drying tower (4) passes through the sixth three-way valve (206) and the needle valve (213) to be produced as product hydrogen, and the remaining part passes through the fourth three-way valve (204) to enter the first drying tower (2) for drying tower regeneration. The gas coming out of the first drying tower (2) passes through the eighth three-way valve (208) to enter the first heat exchanger (16) to exchange heat with hydrogen, and then passes through the first magnetic valve (210) to enter the second cooler (6) and the third gas-water separator (11) to remove part of the water generated by the first drying tower (2); The gas flowing out of the third gas-water separator (11) enters the fourth gas-water separator (12) and the third cooler (7) through the first three-way valve (201) and the second three-way valve (202), then enters the second drying tower (3) for drying through the eighth three-way valve (208), and finally flows into the product hydrogen main circuit through the fifth three-way valve (205).

Images