Method for producing hydrogen and generating electricity by utilizing wastewater

Abstract

The invention discloses a method for producing hydrogen and generating electricity by utilizing wastewater. The method for preparing the hydrogen by utilizing the wastewater comprises the following steps: firstly, pretreating the wastewater, flocculating dissolved matters and fine suspended matters in the wastewater, and then carrying out solid-liquid separation to obtain filtrate and filter residues; then adding the filtrate and active metal into a reaction device of a hydrogen production system, and reacting the filtrate with the active metal to generate hydrogen; and finally, dehydrating and purifying the hydrogen to obtain pure hydrogen. The method for generating power by utilizing the wastewater is realized on the basis of preparing hydrogen by utilizing the wastewater, and specifically, pure hydrogen prepared by utilizing the wastewater is added into a hydrogen power generation system and is subjected to electrochemical reaction with oxygen in air under a specific working condition to generate electric energy and pure water, so that power generation is realized. The method has the advantages that the process is simple, the operation is convenient, high-value utilization of the wastewater can be realized, the wastewater is turned into wealth, and the method is easy to popularize and apply.

Description

Technical Field

[0001] The present invention relates to the technical field of wastewater utilization, and specifically relates to a method for producing hydrogen and generating electricity from wastewater. Background Art

[0002] Wastewater refers to the general term for the water discharged during the activities of residents and the runoff rainwater. It includes domestic sewage, industrial wastewater, and other useless water such as the first rain runoff into the drainage pipe channels, etc. Generally, it refers to the water that cannot be recycled after a certain technical treatment or the water that cannot reach a certain standard after primary pollution and pure treatment. It is also called sewage, which is the water generated during a certain production and living process of humans and has lost its use value or cannot be utilized; discharging wastewater into the environment can cause water pollution.

[0003] Currently, wastewater is increasingly becoming a major matter that the government, enterprises, scientific research and other departments have to pay attention to; the quantity of waste (sewage) water is huge, and the treatment is high in investment and occupies a large area; in recent decades, although the waste (sewage) treatment technology has been changing with each passing day, it still cannot change the current situation of "only input without output, only treatment without utilization".

[0004] The main component in waste (sewage) water is water molecules (H 2 0), and water molecules are the most abundant and easily available hydrogen-carrying compounds, and hydrogen-carrying compounds are the core substances for hydrogen production. Therefore, how to turn waste (sewage) water into a treasure and make waste (sewage) water treatment become a profitable industry has become a difficult problem that needs to be overcome by relevant personnel in the current field. Summary of the Invention

[0005] Aiming at the problems in the background art, the purpose of the present invention is to provide a method for producing hydrogen and generating electricity from wastewater.

[0006] To achieve the above purpose, the technical solutions adopted by the present invention are as follows:

[0007] On the one hand, the present invention provides a method for producing hydrogen from wastewater, which includes the following steps:

[0008] S101. Pump the wastewater into a pretreatment device, and add 0.1-10% of a flocculant to the pretreatment device in proportion; stir evenly, and let it stand for 5-10 minutes, and then perform solid-liquid separation to obtain filter residue and filtrate;

[0009] S102. Add the filtrate in S101 into the jacketed reaction device of the hydrogen production system, and add a quantitative amount of active metal into the jacketed reaction device of the hydrogen production system. React the active metal with the filtrate to generate hydrogen. Among them, the hydrogen production system includes a jacketed reaction device, a draft fan, a drying section, a purification device, a compressor, and a hydrogen storage tank. The jacketed reaction device is connected to the draft fan, the draft fan is connected to the drying section, the drying section is connected to the purification device, the purification device is connected to the compressor, and the compressor is connected to the hydrogen storage tank.

[0010] S103. Quickly extract the hydrogen produced in S102 from the jacketed reaction device through the draft fan, and transport it to the drying section. After dehydration in the drying section, it is purified by the purification device to obtain pure hydrogen.

[0011] S104. Compress the pure hydrogen produced in S103 by a compressor and pump it into the hydrogen storage tank for storage.

[0012] Further, the wastewater is industrial wastewater, domestic sewage, or nuclear wastewater.

[0013] Further, the flocculant includes any one component or any combination of two or more components of polyaluminum chloride, polyferric sulfate, polyaluminum sulfate, poly(dimethyldiallylammonium chloride), polyacrylamide, or polyferrous.

[0014] Further, the active metal is an alkali metal, an alkaline earth metal, a transition metal, or aluminum.

[0015] Further, the jacketed reaction device includes an outer shell, an inner shell, a jacket provided between the outer shell and the inner shell, and a water inlet, a chemical inlet, a hydrogen outlet, and a precipitate outlet that communicate with the inner shell and penetrate through the jacket and the outer shell. The outer shell is made of stainless steel. The inner shell is hot-pressed from a mixture of 1% - 50% by mass of carbon fiber, 90% - 1% by mass of copper-aluminum alloy, and 1% - 50% by mass of graphite. The inside of the jacket is filled with a refrigerant, and the refrigerant is freon, liquid ammonia, lithium bromide, carbon dioxide, liquid hydrogen, or liquid nitrogen.

[0016] Further, the inside of the drying section is filled with a desiccant composed of any one of oxides of alkali metals, chlorides of alkali metals, oxides of alkaline earth metals, chlorides of alkaline earth metals, or acidic desiccants, or a desiccant composed of any two or more of them.

[0017] Further, the purification device is composed of three layers of inner, middle, and outer membranes. The inner and outer membranes are both made of PCL plastic, and the middle membrane is made of a composite of 90% - 10% by mass of metallic palladium and 10% - 90% by mass of vanadium.

[0018] Further, the hydrogen storage tank is formed by winding a hybrid fiber composed of 10% - 90% by mass of carbon fiber and 90% - 10% by mass of aramid fiber on the outer side of an aluminum alloy inner liner.

[0019] On the other hand, the present invention provides a method for generating electricity using wastewater, comprising the following steps:

[0020] S201: Prepare pure hydrogen according to the steps of S101 - S103 in the method for producing hydrogen using wastewater described above;

[0021] S202: Pump the pure hydrogen prepared in S201 into a hydrogen power generation system through a compressor, and in the hydrogen power generation system, an electrochemical reaction occurs between the hydrogen and oxygen in the air under specific working conditions to generate electric energy and pure water;

[0022] Among them, the hydrogen power generation system is a hydrogen fuel cell;

[0023] Among them, the specific working conditions include four indicators: temperature of 80 - 110 °C, pressure of 1 - 3 MPa, a specific catalyst, and a specific electrode.

[0024] Further, the specific catalyst is a catalyst composed of 90% - 10% by mass of platinum and 10% - 90% by mass of perovskite, and the specific electrode is an electrode doped with 0.1% - 10% by mass of graphene.

[0025] Compared with the prior art, the advantages of the present invention are as follows:

[0026] (1) The process is simple and easy to operate, can highly utilize wastewater, turn waste into treasure, and is easy to promote and apply.

[0027] (2) During the hydrogen production process, the "interlayer cooling method" is adopted to strictly control the temperature in the reaction device of the hydrogen production system, ensuring that the temperature is always within a relatively suitable range when wastewater reacts with active metals to produce hydrogen; in addition, the "interlayer cooling method" adopted in the present invention is realized by integrating the reaction device and the cooling device, effectively saving equipment and space. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the technical solutions in this embodiment, the following will briefly introduce the drawings required for the description of the embodiment; obviously, the following described drawings are only some embodiments of the present invention, and for those of ordinary skill in the art, other drawings can be obtained according to these drawings without creative efforts.

[0029] Figure 1 is the process flow chart of the method for producing hydrogen using wastewater provided by the present invention;

[0030] Figure 2 It is the process flow diagram of the method for generating electricity using wastewater provided by the present invention;

[0031] Figure 3 It is the schematic structural diagram of the hydrogen production system used in the method for producing hydrogen using wastewater provided by the present invention;

[0032] Figure 4 It is the cross-sectional view of the reaction device with a sandwich layer;

[0033] Explanation of reference numerals in the drawings: 1. Reaction device with a sandwich layer; 101. Outer housing; 102. Inner housing; 103. Sandwich layer; 104. Water inlet; 105. Chemical inlet; 106. Hydrogen outlet; 107. Precipitate outlet; 2. Induced draft fan; 3. Drying section; 4. Purification device; 5. Compressor; 6. Hydrogen storage tank. Detailed implementation manners

[0034] To make the technical means, creative features, achieved purposes and functions of the present invention easy to understand, the following further elaborates how the present invention is implemented in combination with the drawings and specific implementation manners.

[0035] Refer to Figure 1 , the present invention provides a method for producing hydrogen using wastewater, comprising the following steps:

[0036] S101. Pump the wastewater into the pretreatment device, and add 0.1 - 10% of flocculant to the pretreatment device in proportion; stir evenly, stand for 5 - 10 min, and then perform solid-liquid separation to obtain filter residue and filtrate; among them, the pretreatment device is prior art, such as an underground reservoir or an above-ground container;

[0037] S102. Add the filtrate in S101 to the reaction device 1 with a sandwich layer in the hydrogen production system, and add a certain amount of active metal to the reaction device 1 with a sandwich layer in the hydrogen production system, and use the active metal to react with the filtrate to generate hydrogen; refer to Figure 3 , wherein, the hydrogen production system comprises a reaction device 1 with a sandwich layer, an induced draft fan 2, a drying section 3, a purification device 4, a compressor 5 and a hydrogen storage tank 6; the reaction device 1 with a sandwich layer is connected to the induced draft fan 2, the induced draft fan 2 is connected to the drying section 3, the drying section 3 is connected to the purification device 4, the purification device 4 is connected to the compressor 5, and the compressor 5 is connected to the hydrogen storage tank 6;

[0038] S103. Rapidly extract the hydrogen produced in S102 from the reaction device 1 with a sandwich layer through the induced draft fan 2, and transport it to the drying section 3; after dehydration in the drying section 3, it is purified by the purification device 4 to obtain pure hydrogen;

[0039] S104. Compress the pure hydrogen produced in S103 by the compressor 5 and pump it into the hydrogen storage tank 6 for storage.

[0040] Specifically, the wastewater is industrial wastewater, domestic sewage or nuclear wastewater.

[0041] Specifically, the flocculant includes any one component or any combination of two or more components of polyaluminum chloride, polyferric sulfate, polyaluminum sulfate, polydimethyldiallylammonium chloride, polyacrylamide or polyferrous. The function of the flocculant is to aggregate the dissolved substances and fine suspended solids in the wastewater into flocs with separable characteristics.

[0042] Specifically, the active metal is an alkali metal, an alkaline earth metal, a transition metal or aluminum.

[0043] Specifically, refer to Figure 4 , the sandwich reaction device 1 includes an outer shell 101, an inner shell 102, a sandwich 103 disposed between the outer shell 101 and the inner shell 102, and a water inlet 104, a chemical inlet 105, a hydrogen outlet 106 and a precipitate outlet 107 that communicate with the inner shell 102 and penetrate through the sandwich 103 and the outer shell 101; wherein, the water inlet 104 is a wastewater inlet, the chemical inlet 105 is an active metal inlet, and the hydrogen outlet 106 is used to connect with the induced draft fan 2; the precipitate outlet 107 is used to discharge the precipitate, and a corresponding solenoid valve is also provided thereon to control its on and off.

[0044] More specifically, the outer shell 101 is made of stainless steel, and the inner shell 102 is formed by hot pressing a mixture of 1% - 50% by mass of carbon fiber, 90% - 1% by mass of copper-aluminum alloy and 1% - 50% by mass of graphite; the sandwich 103 is filled with a refrigerant, and the refrigerant is freon, liquid ammonia, lithium bromide, carbon dioxide, liquid hydrogen or liquid nitrogen.

[0045] Specifically, the drying section 3 is filled with a desiccant composed of any one of oxides of alkali metals, chlorides of alkali metals, oxides of alkaline earth metals, chlorides of alkaline earth metals or acidic desiccants, or a desiccant composed of any two or more of them.

[0046] Specifically, the purification device 4 is composed of an inner, middle and outer three-layer composite membrane. The inner layer membrane and the outer layer membrane are both made of PCL plastic, and the middle layer membrane is made of a composite composed of 90% - 10% by mass of metallic palladium and 10% - 90% by mass of vanadium. Among them, the inner layer membrane and the outer layer membrane only allow small molecule gases to pass through; the middle layer membrane only allows H 2 to diffuse and pass through; there are gaps between the inner, middle and outer three-layer membranes.

[0047] Specifically, the hydrogen storage tank 6 is formed by winding a mixed fiber composed of 10% - 90% by mass of carbon fiber and 90% - 10% by mass of aramid fiber on the outside of an aluminum alloy inner liner.

[0048] To further understand how the method for producing hydrogen using wastewater provided by the present invention is implemented, several specific embodiments are introduced below for illustration:

[0049] Embodiment 1: In this example, hydrogen is specifically prepared by reacting industrial wastewater with metallic sodium. The steps are as follows:

[0050] First step, the industrial wastewater is simply and roughly filtered to remove obvious particulate matters, floating oil and other sundries, then pumped into the pretreatment device. Then, a flocculant polyaluminum chloride with a mass fraction of 1% is added in proportion, stirred evenly, and after standing for 5 minutes, solid-liquid separation is carried out by a plate and frame filter press to obtain filter residue and filtrate;

[0051] Second step, the filtrate is added to the jacketed reaction device 1 of the hydrogen production system, and a quantitative amount of metallic sodium is added to the jacketed reaction device 1 of the hydrogen production system. Hydrogen is generated by the reaction of metallic sodium with the filtrate;

[0052] Third step, the hydrogen produced is quickly drawn out from the jacketed reaction device 1 by the induced draft fan 2 of the hydrogen production system and transported to the drying section 3 of the hydrogen production system; after dehydration in the drying section 3, it is then purified by the purification device 4 of the hydrogen production system to obtain pure hydrogen;

[0053] Fourth step, the pure hydrogen produced is compressed by the compressor 5 of the hydrogen production system and then pumped into the hydrogen storage tank 6 of the hydrogen production system for storage.

[0054] Specifically, in this Embodiment 1, the outer shell 101 of the jacketed reaction device 1 is made of ordinary stainless steel; the inner shell 102 is formed by hot pressing a mixture of 35% by mass of carbon fiber, 55% by mass of copper-aluminum alloy and 10% by mass of graphite; dry ice is used as a refrigerant inside the jacket 103 to ensure that the working temperature inside the jacketed reaction device is controlled at 60 °C. The drying section 3 is filled with a high-efficiency desiccant composed of 40% by mass of solid sodium hydroxide, 50% by mass of anhydrous calcium chloride and 10% by mass of lithium bromide. The intermediate layer membrane of the purification device 4 is made of a composite composed of 70% by mass of metallic palladium and 30% by mass of vanadium. The hydrogen storage tank 6 is formed by winding a mixed fiber composed of 80% by mass of carbon fiber and 20% by mass of aramid fiber on the outside of an aluminum alloy inner liner.

[0055] After testing, in this Embodiment 1, the purity of the hydrogen purified by the purification device 4 reaches 99.9999%.

[0056] Embodiment 2: In this example, hydrogen is specifically prepared by reacting domestic sewage with metallic calcium. The steps are as follows:

[0057] First step, pump domestic sewage into the pretreatment device, and then add polyacrylamide flocculant with a mass fraction of 0.8% in proportion; stir evenly, and after standing for 8 min, carry out solid-liquid separation by a heavy-duty filter press to obtain filter residue and filtrate;

[0058] Second step, add the filtrate into the jacketed reaction device 1 of the hydrogen production system, and add a certain amount of metallic calcium into the jacketed reaction device 1 of the hydrogen production system, and use the metallic calcium to react with the filtrate to generate hydrogen;

[0059] Third step, quickly extract the produced hydrogen from the jacketed reaction device 1 through the induced draft fan 2 of the hydrogen production system, and transport it to the drying section 3 of the hydrogen production system; after dehydration in the drying section 3, it is purified by the purification device 4 of the hydrogen production system to obtain pure hydrogen;

[0060] Fourth step, compress the obtained pure hydrogen by the compressor 5 of the hydrogen production system and then pump it into the hydrogen storage tank 6 of the hydrogen production system for storage.

[0061] Specifically, in this Example 2, the outer shell 101 of the jacketed reaction device 1 is made of ordinary stainless steel; the inner shell 102 is formed by hot pressing a mixture of 40% carbon fiber by mass, 45% copper-aluminum alloy by mass, and 15% graphite by mass; the inside of the interlayer 103 uses liquid ammonia as a refrigerant to ensure that the working temperature inside the jacketed reaction device is controlled at 62 °C. The inside of the drying section 3 is filled with a high-efficiency desiccant composed of 50% anhydrous calcium chloride by mass and 50% anhydrous copper sulfate by mass. The intermediate layer membrane of the purification device 4 is made of a composite composed of 60% metallic palladium by mass and 40% vanadium by mass. The hydrogen storage tank 6 is formed by winding a mixed fiber composed of 75% carbon fiber by mass and 25% aramid fiber by mass on the outside of an aluminum alloy inner liner.

[0062] After testing, in this Example 2, the purity of the hydrogen purified by the purification device 4 reaches 99.9991%.

[0063] Example 3: In this example, specifically, nuclear wastewater is used to react with metallic lithium to prepare hydrogen, and the steps are as follows:

[0064] First step, pump nuclear wastewater into the pretreatment device, and then add a flocculant with a mass fraction of 1.2% in proportion; stir evenly, and after standing for 10 min, carry out solid-liquid separation by a filter press to obtain filter residue and filtrate; the flocculant is composed of 50% polyaluminum chloride by mass and 50% polyacrylamide by mass;

[0065] Second step, add the filtrate into the jacketed reaction device 1 of the hydrogen production system, and add a certain amount of metallic lithium into the jacketed reaction device 1 of the hydrogen production system, and use the metallic lithium to react with the filtrate to generate hydrogen;

[0066] In the third step, the produced hydrogen is quickly extracted from the reaction device 1 with a sandwich by the induced draft fan 2 of the hydrogen production system and transported to the drying section 3 of the hydrogen production system; after dehydration in the drying section 3, it is purified by the purification device 4 of the hydrogen production system to obtain pure hydrogen;

[0067] In the fourth step, the obtained pure hydrogen is compressed by the compressor 5 of the hydrogen production system and then pumped into the hydrogen storage tank 6 of the hydrogen production system for storage.

[0068] Specifically, in this Embodiment 3, the outer shell 101 of the reaction device 1 with a sandwich is made of ordinary stainless steel; the inner shell 102 is formed by hot pressing a mixture of 50% carbon fiber, 45% copper-aluminum alloy, and 5% graphite by mass fraction; liquid ammonia is used as a refrigerant inside the sandwich 103 to control the working temperature inside the reaction device with a sandwich at 65°C. The drying section 3 is filled with an efficient desiccant composed of 50% anhydrous calcium chloride, 25% anhydrous copper sulfate, and 25% silica gel by mass fraction. The intermediate layer membrane of the purification device 4 is made of a composite composed of 80% palladium metal and 20% vanadium by mass fraction. The hydrogen storage tank 6 is formed by winding a hybrid fiber composed of 70% carbon fiber and 30% aramid fiber by mass fraction on the outside of an aluminum alloy inner liner.

[0069] After testing, in this Embodiment 3, the purity of the hydrogen purified by the purification device 4 reaches 99.9992%.

[0070] In addition, in this Example 3, when metallic lithium reacts with the filtrate to produce hydrogen, all the inclusions (including nuclear waste) in the filtrate will form a precipitate together; this precipitate needs to be combined with the filter residue in the first step and buried deeply, so as to completely solve the hidden dangers and concerns brought by nuclear wastewater pollution and discharging into the ocean, rivers, and lakes; compared with the high investment required for general nuclear wastewater treatment, the present invention can turn nuclear wastewater into a source of hydrogen and electricity, making the treatment of nuclear wastewater a profitable business.

[0071] Refer to Figure 2 , the present invention also provides a method for generating electricity by using wastewater, comprising the following steps:

[0072] S201. Obtain pure hydrogen according to the steps of S101 to S103 in the above method for producing hydrogen by using wastewater;

[0073] S202. Pump the pure hydrogen obtained in S201 into the hydrogen power generation system through the compressor 5, and in the hydrogen power generation system, an electrochemical reaction occurs with oxygen in the air under specific working conditions to generate electric energy and pure water;

[0074] Among them, the hydrogen power generation system is a hydrogen fuel cell, which is a closed system composed of a proton exchange membrane, a catalyst, and electrodes;

[0075] Among them, the specific operating conditions include four indicators: temperature of 80 - 110 °C, pressure of 1 - 3 MPa, specific catalyst, and specific electrode.

[0076] Specifically, the specific catalyst is a catalyst composed of platinum with a mass fraction of 90% - 10% and perovskite with a mass fraction of 10% - 90%; compared with the common single platinum catalyst, the catalytic efficiency is 39.7% higher.

[0077] Specifically, the specific electrode is an electrode doped with graphene with a mass fraction of 0.1% - 10%, which can significantly increase the electrode stability.

[0078] In order to further understand how the method for generating electricity using wastewater provided by the present invention is implemented, several specific embodiments are introduced below for illustration:

[0079] Embodiment 4: In this embodiment, specifically, based on the reaction of industrial wastewater with metallic sodium to produce hydrogen, the produced hydrogen reacts electrochemically with oxygen in the air to generate electric energy and achieve power generation. The specific steps are as follows:

[0080] The first step: Prepare pure hydrogen according to the first to third steps in the method for producing hydrogen using wastewater in Embodiment 1 above;

[0081] The second step: Pump the produced pure hydrogen into the hydrogen power generation system through a compressor 5, and in the hydrogen power generation system, it reacts electrochemically with oxygen in the air under the operating conditions of a temperature of 85 °C, a pressure of 1.5 MPa, a specific catalyst composed of platinum with a mass fraction of 60% and perovskite with a mass fraction of 40%, and a specific electrode doped with graphene with a mass fraction of 2.5% to generate electric energy and pure water.

[0082] After testing, in this embodiment, each kilogram of hydrogen can generate 15.8 degrees of electricity.

[0083] Embodiment 5: In this example, specifically, based on the reaction of domestic sewage with metallic calcium to prepare hydrogen, the produced hydrogen reacts electrochemically with oxygen in the air to generate electric energy and achieve power generation. The specific steps are as follows:

[0084] The first step: Prepare pure hydrogen according to the first to third steps in the method for producing hydrogen using wastewater in Embodiment 2 above;

[0085] Step 2: Pump the prepared pure hydrogen into the hydrogen power generation system through compressor 5, and in the hydrogen power generation system, an electrochemical reaction occurs between the hydrogen and the oxygen in the air under the working conditions of a temperature of 90 °C, a pressure of 1.8 MPa, a specific catalyst composed of 65% by mass of platinum and 35% by mass of perovskite, and a specific electrode doped with 3% by mass of graphene, generating electric energy and pure water.

[0086] After testing, in this embodiment, every kilogram of hydrogen can generate 15.9 kWh of electricity.

[0087] Example 6: In this example, specifically based on the reaction between nuclear wastewater and metallic lithium to prepare hydrogen, the prepared hydrogen reacts electrochemically with the oxygen in the air to generate electric energy and achieve power generation. The specific steps are as follows:

[0088] Step 1: Prepare pure hydrogen according to the first to third steps in the method for preparing hydrogen from wastewater in Example 3 above;

[0089] Step 2: Pump the prepared pure hydrogen into the hydrogen power generation system through compressor 5, and in the hydrogen power generation system, an electrochemical reaction occurs between the hydrogen and the oxygen in the air under the working conditions of a temperature of 95 °C, a pressure of 2 MPa, a specific catalyst composed of 70% by mass of platinum and 30% by mass of perovskite, and a specific electrode doped with 3.5% by mass of graphene, generating electric energy and pure water.

[0090] After testing, in this embodiment, every kilogram of hydrogen can generate 16.1 kWh of electricity.

[0091] Finally, it should be noted that the above are only embodiments of the present invention, and do not limit the patent scope of the present invention accordingly; all equivalent structural or equivalent process transformations made by using the content of the specification and drawings of the present invention, or directly or indirectly applied to other related technical fields, are equally included in the patent protection scope of the present invention.

Claims

1. A method for producing hydrogen using wastewater, characterized in that: The following steps are included: S101, pumping the wastewater into the pretreatment device, and adding 0.1-10% flocculant to the pretreatment device in proportion, stirring evenly, and standing for 5N10min, and then performing solid-liquid separation to obtain filter residue and filtrate; S102, adding the filtrate in S101 to a sandwich reaction device (1) of a hydrogen production system, and adding a certain amount of active metal to the sandwich reaction device (1) of the hydrogen production system, and utilizing the active metal to react with the filtrate to generate hydrogen; wherein the hydrogen production system comprises a sandwich reaction device (1), an induced draft fan (2), a drying section (3), a purification device (4), a compressor (5) and a hydrogen storage tank (6); the sandwich reaction device (1) is connected to the induced draft fan (2), the induced draft fan (2) is connected to the drying section (3), the drying section (3) is connected to the purification device (4), the purification device (4) is connected to the compressor (5), and the compressor (5) is connected to the hydrogen storage tank (6); S103, the hydrogen produced in S102 is quickly extracted from the sandwich reaction device (1) through the induced draft fan (2), and transported to the drying section (3); after being dehydrated in the drying section (3), it is purified by the purification device (4) to obtain pure hydrogen; S104, the pure hydrogen produced in S103 is compressed by a compressor (5) and then pumped into a hydrogen storage tank (6) for storage.

2. The method for producing hydrogen using wastewater according to claim 1, characterized in that: The wastewater is industrial wastewater, domestic sewage or nuclear wastewater.

3. The method for producing hydrogen using wastewater according to claim 1, characterized in that: The flocculant includes any one of polyaluminium chloride, polyferric sulfate, polyaluminium sulfate, polydimethyldiallylammonium chloride, polyacrylamide or polyferrous iron, or a combination of any two or more of the above.

4. The method for producing hydrogen using wastewater according to claim 1, characterized in that: The active metal is an alkali metal, an alkaline earth metal, a transition metal or aluminum.

5. The method for producing hydrogen using wastewater according to claim 1, characterized in that: The sandwich reaction device (1) comprises an outer shell (101), an inner shell (102), a sandwich (103) arranged between the outer shell (101) and the inner shell (102), and a water inlet (104), a chemical inlet (105), a hydrogen outlet (106) and a sediment outlet (107) communicating with the inner shell (102) and penetrating the sandwich (103) and the outer shell (101); the outer shell (101) is made of stainless steel, and the inner shell (102) is formed by hot pressing after mixing carbon fiber with a mass fraction of 1% to 50%, copper-aluminum alloy with a mass fraction of 90% to 1%, and graphite with a mass fraction of 1% to 50%; the interior of the sandwich (103) is filled with a refrigerant, and the refrigerant is freon, liquid ammonia, lithium bromide, carbon dioxide, liquid hydrogen or liquid nitrogen.

6. The method for producing hydrogen using wastewater according to claim 1, characterized in that: The drying section (3) is filled with a desiccant consisting of any one of alkali metal oxides, alkali metal chlorides, alkaline earth metal oxides, alkaline earth metal chlorides or acidic desiccants, or a desiccant consisting of any two or more of the above.

7. The method for producing hydrogen using wastewater according to claim 1, characterized in that: The purification device (4) is composed of three layers of membranes, inner, middle and outer, wherein the inner and outer membranes are both made of PCL plastic, and the middle membrane is made of a composite material consisting of 90% to 10% by mass of metal palladium and 10% to 90% by mass of vanadium.

8. The method for producing hydrogen using wastewater according to claim 1, characterized in that: The hydrogen storage tank (6) is formed by winding mixed fibers consisting of 10% to 90% by mass of carbon fibers and 90% to 10% by mass of aramid fibers around the outside of an aluminum alloy inner liner.

9. A method for generating electricity using wastewater, characterized in that: The following steps are included: S201, producing pure hydrogen according to steps S101 to S103 of the method for producing hydrogen using wastewater according to claim 1; S202, pumping the pure hydrogen produced in S201 into a hydrogen power generation system through a compressor (5), and causing an electrochemical reaction with oxygen in the air under specific working conditions in the hydrogen power generation system to generate electrical energy and pure water; Among them, the hydrogen power generation system is a hydrogen fuel cell; Among them, the specific operating conditions include four indicators: temperature 80-110°C, pressure 1-3MPa, specific catalyst and specific electrode.

10. The method for generating electricity using wastewater according to claim 9, characterized in that: The specific catalyst is a catalyst composited by 90% to 10% platinum by mass and 10% to 90% perovskite by mass, and the specific electrode is an electrode doped with 0.1% to 10% graphene by mass.

Images