Method for improving quality of agricultural products by electrolyzing water to produce hydrogen

Abstract

The invention provides a method for improving the quality of agricultural products by electrolyzing water to produce hydrogen. The method comprises the following steps: carrying out electrolytic reaction on KOH electrolyte to obtain hydrogen and oxygen; hydrogen is injected into water through a gas dissolver, so that the hydrogen reaches a saturated or super-saturated state in the water to obtain hydrogen-rich water, and the hydrogen-rich water is fed into an agricultural irrigation area; oxygen is fed into the agricultural irrigation area to serve as a night oxygen source; a solution hydrogen concentration sensor is arranged in the agricultural irrigation area, and the KOH sample injection amount of the electrolyte tank is controlled according to the solution hydrogen concentration of the agricultural irrigation area. The KOH electrolyte is electrolyzed to produce hydrogen and prepare hydrogen-rich water, then the hydrogen-rich water is applied to agricultural irrigation, oxygen is supplied at night, and the quality of agricultural products is improved; and the electrolysis hydrogen production process can be flexibly controlled according to the solution hydrogen concentration of an agricultural irrigation area, preparation efficiency and safety can be both considered, and the method is particularly suitable for areas with good wind and light resources and developed agriculture.

Description

Technical Field

[0001] The invention relates to the technical field of agriculture, and in particular to a method for producing hydrogen by electrolyzing water for improving the quality of agricultural products. Background Art

[0002] Hydrogen agronomy is not only a laboratory-based study but also has potential applications in agricultural production, known as hydrogen farming, which aims to grow food in an affordable, healthy and sustainable way for humans. Hydrogen agronomy mainly focuses on the molecular mechanism of hydrogen-rich water (HRW) or hydrogen gas improving the quality of agricultural products.

[0003] Hydrogen is mainly used in agriculture in the form of hydrogen-rich water. Hydrogen-rich water is a type of water rich in hydrogen. There are many ways to prepare it. The main preparation methods are as follows:

[0004] Electrolysis. The principle is to use an electrolysis device to decompose water into hydrogen and oxygen, and then dissolve hydrogen in water through special design to produce hydrogen-rich water. The process usually uses a special electrolytic cell to divide the water into two parts, the anode and the cathode. During the electrolysis process, the anode produces oxygen, and the cathode produces hydrogen and dissolves in the water to form hydrogen-rich water. Electrolysis is one of the most commonly used methods for preparing hydrogen-rich water, and the technology is mature and stable. However, the efficiency and safety of electrolysis technology are also factors that need to be considered.

[0005] Metal-acid reaction method. The principle is that certain metals react with water to produce hydrogen, which is then dissolved in water to form hydrogen-rich water. The process is to place a metal (such as magnesium) in water, and the metal reacts with water molecules to produce hydrogen and metal hydroxide. By controlling the reaction conditions, hydrogen can be collected and dissolved in water. This method can quickly produce hydrogen and prepare hydrogen-rich water, but it may introduce metal ion contamination, and the metal filler needs to be replaced regularly to ensure the hydrogen production effect. In addition, the reaction of metals with water may change the pH of the water and affect the water quality.

[0006] Hydrogen-enriched water mass dissolution method. The principle is to inject hydrogen directly into water under high pressure to dissolve it in water to achieve the purpose of preparing hydrogen-enriched water. The process is to place water and hydrogen in a high-pressure container and dissolve hydrogen in water by increasing the pressure. This method requires specialized equipment and technical support and is usually suitable for industrial or laboratory environments. The hydrogen-enriched water prepared by this method has a higher hydrogen concentration, but the equipment cost is high and the operation is complicated.

[0007] Catalytic method. The principle is to use a catalyst to accelerate the hydrogen generation reaction in water and increase the hydrogen concentration of hydrogen-rich water. The process is to contact the catalyst (such as platinum, palladium, iron and other metals) with water for a period of time. The catalyst will absorb the hydrogen in the water and accelerate its generation reaction. The catalytic method can increase the hydrogen concentration of hydrogen-rich water and the operation is relatively simple, but the cost and stability of the catalyst are factors that need to be considered.

[0008] Ultraviolet method. The principle is to use ultraviolet rays to irradiate water molecules, break the hydrogen bonds in the water molecules and stimulate the hydrogen in the water to form hydrogen-rich water. The process is to expose pure water to an ultraviolet light source, which will act on the water molecules and release hydrogen. The ultraviolet method is simple to operate and does not require the addition of any chemicals, but the hydrogen concentration of the prepared hydrogen-rich water is relatively low and may be limited by the ultraviolet light source.

[0009] Therefore, the current method for preparing hydrogen-rich water for agricultural use still cannot take into account both preparation efficiency and safety. Summary of the invention

[0010] The main purpose of the present invention is to provide a method for producing hydrogen by electrolyzing water for improving the quality of agricultural products, so as to solve the problem that the preparation method of hydrogen-rich water in the prior art cannot take into account both preparation efficiency and safety, thus affecting its application in agriculture.

[0011] In order to achieve the above-mentioned purpose, according to one aspect of the present invention, there is provided a method for producing hydrogen by electrolyzing water for improving the quality of agricultural products, comprising the following steps: step S1, feeding water and KOH in an electrolyte tank into an electrolytic cell, mixing to obtain a KOH electrolyte, applying electricity to carry out an electrolysis reaction, and obtaining hydrogen and oxygen; step S2, injecting hydrogen into water through a gas dissolver, so that the hydrogen reaches a saturated or supersaturated state in the water, obtaining hydrogen-rich water, and feeding the hydrogen-rich water into an agricultural irrigation area; step S3, feeding oxygen into the agricultural irrigation area as a nighttime oxygen source; wherein a solution hydrogen concentration sensor is provided in the agricultural irrigation area to control the KOH injection amount of the electrolyte tank according to the solution hydrogen concentration in the agricultural irrigation area.

[0012] Furthermore, the mass concentration of the KOH electrolyte is 5-30%.

[0013] Furthermore, the mass concentration of hydrogen-rich water is 1 to 10%.

[0014] Furthermore, the electrolytic cell includes a cathode electrode, a diaphragm, an anode electrode and a bipolar plate, and the material of the diaphragm is polyphenylene sulfide, a proton exchange membrane or yttria-stabilized zirconia.

[0015] Furthermore, when the material of the diaphragm is polyphenylene sulfide, the hydrogen production pressure of the electrolyzer is 0.1-3.2 MPa, and the current density is 0.2-0.4 A / cm 2 .

[0016] Furthermore, when the material of the diaphragm is a proton exchange membrane, the hydrogen production pressure of the electrolyzer is 0.1-5.0 MPa, and the current density is 1.0-2.0 A / cm 2 .

[0017] Furthermore, when the material of the diaphragm is yttria-stabilized zirconia, the hydrogen production pressure of the electrolyzer is 0.1-1.5 MPa, and the current density is 0.3-1.0 A / cm 2 .

[0018] Furthermore, the working temperature of the electrolytic cell is 70-90°C; and / or the volume of the electrolytic cell is 20-50 Nm 3 / h.

[0019] Furthermore, the method also includes the step of sending the waste liquid from the electrolytic cell into a potash fertilizer preparation system to obtain potash fertilizer and sending it to an agricultural irrigation area.

[0020] Furthermore, the electricity source of the electrolyzer includes wind power generation and / or photovoltaic power generation.

[0021] By applying the technical solution of the present invention, hydrogen is produced by electrolyzing KOH electrolyte and hydrogen-rich water is prepared, and then the hydrogen-rich water is applied to agricultural irrigation, and oxygen is used for nighttime oxygen supply to improve the quality of agricultural products. The method of the present invention can also flexibly control the electrolytic hydrogen production process according to the hydrogen concentration of the solution in the agricultural irrigation area, and can take into account both the preparation efficiency and safety, and is particularly suitable for areas with good wind and light resources and developed agriculture. The present invention utilizes electrolytic hydrogen production to prepare hydrogen-rich water. The whole process is pollution-free and emission-free, meets environmental protection requirements, and electrolyzed water, as a renewable energy source, has the advantage of sustainable utilization. Compared with traditional agricultural irrigation methods, the use of hydrogen-rich water for irrigation can reduce the use of fertilizers and pesticides, which is conducive to reducing production costs and improving economic benefits. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The drawings constituting a part of the present application are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0023] Figure 1 A schematic diagram of the structure of an electrolytic cell according to an embodiment of the present invention is shown; and

[0024] Figure 2 A flow chart of a method for producing hydrogen by electrolyzing water for improving the quality of agricultural products according to an embodiment of the present invention is shown.

[0025] The above drawings include the following reference numerals:

[0026] 1. Solid screw; 2. Cathode electrode; 3. Diaphragm; 4. Anode electrode; 5. Gasket; 6. Bipolar plate; 7. KOH electrolyte inlet; 8. KOH electrolyte outlet; 9. H2 outlet; 10. O2 outlet. DETAILED DESCRIPTION

[0027] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0028] As described in the background of the present invention, there is a problem in the prior art that the preparation method of hydrogen-rich water cannot take into account both preparation efficiency and safety, which affects its application in agriculture. In order to solve the above problems, in a typical embodiment of the present invention, a method for electrolyzing water to produce hydrogen for improving the quality of agricultural products is provided, comprising the following steps: step S1, water and KOH in an electrolyte tank are sent into an electrolytic cell, mixed to obtain a KOH electrolyte, and energized to perform an electrolysis reaction to obtain hydrogen and oxygen; step S2, hydrogen is injected into water through a gas dissolver to make hydrogen reach a saturated or supersaturated state in the water to obtain hydrogen-rich water, and the hydrogen-rich water is sent to an agricultural irrigation area; step S3, oxygen is sent to the agricultural irrigation area as a night oxygen source; wherein a solution hydrogen concentration sensor is set in the agricultural irrigation area to control the KOH injection amount of the electrolyte tank according to the solution hydrogen concentration in the agricultural irrigation area.

[0029] The present invention first feeds water and KOH in an electrolyte tank into an electrolytic cell, mixes them in the electrolytic cell to obtain a KOH electrolyte, and then energizes the electrolytic cell to perform an electrolytic reaction to obtain hydrogen and oxygen. The KOH electrolyte undergoes electrolysis in the electrolytic cell, generates hydrogen at the cathode, and generates oxygen at the anode, and the oxygen and hydrogen can be collected separately.

[0030] Hydrogen is then injected into the water through a gas dissolver to make the hydrogen in the water reach a saturated or supersaturated state, and the hydrogen-rich water is sent to the agricultural irrigation area to replace or partially replace the traditional irrigation water source. The biological activity and antioxidant properties of hydrogen-rich water are used to promote plant growth and improve the quality of agricultural products. At the same time, oxygen is sent to the agricultural irrigation area as a nighttime oxygen source to supply the plants with nighttime respiration.

[0031] Since different crops have different requirements for hydrogen-rich water concentration, the method of the present invention also sets a solution hydrogen concentration sensor in the agricultural irrigation area, and transmits the solution hydrogen concentration in the agricultural irrigation area back to the electrolyzer. The electrolyzer can further control the concentration of the KOH electrolyte by controlling the KOH injection amount of the electrolyte tank according to the returned hydrogen concentration, thereby achieving a promoting effect on different crops. It can be understood that when the solution hydrogen concentration transmitted back from the agricultural irrigation area is lower than the hydrogen-rich water concentration required by the crop, the injection amount of the electrolyte tank is increased to increase the concentration of the KOH electrolyte; when the solution hydrogen concentration transmitted back from the agricultural irrigation area is higher than the hydrogen-rich water concentration required by the crop, the injection amount of the electrolyte tank is reduced to reduce the concentration of the KOH electrolyte. These are understandable to those skilled in the art and will not be repeated here.

[0032] Hydrogen-rich water can significantly improve the quality of agricultural products, including nutritional value, taste and appearance, through its unique biological activity and antioxidant properties. Hydrogen-rich water can be used as an alternative to pesticides to prevent and disinfect crop diseases without leaving harmful residues. Hydrogen-rich water also contains rich ionic calcium, magnesium, potassium and other elements, which can promote the absorption and growth and development of crops. Hydrogen-rich water can promote the activity of antioxidant enzymes in plants, remove excessive free radicals, alleviate plant stress, and improve plant resistance (such as drought resistance, salt and alkali resistance, etc.) through its biological activity and antioxidant properties. Hydrogen-rich water can also promote the growth and development of plants, increase the germination rate of seeds, the elongation rate of stems and roots, and the growth of seedling roots, thereby improving the yield and quality of agricultural products.

[0033] In summary, the present invention produces hydrogen and prepares hydrogen-rich water by electrolyzing KOH electrolyte, and then applies hydrogen-rich water to agricultural irrigation, and oxygen is used for nighttime oxygen supply to improve the quality of agricultural products. The method of the present invention can also flexibly control the electrolytic hydrogen production process according to the hydrogen concentration of the solution in the agricultural irrigation area, and can take into account both preparation efficiency and safety, and is particularly suitable for areas with good wind and light resources and developed agriculture. The present invention uses electrolytic hydrogen to prepare hydrogen-rich water. The whole process is pollution-free and emission-free, meets environmental protection requirements, and electrolyzed water, as a renewable energy source, has the advantage of sustainable utilization. Compared with traditional agricultural irrigation methods, the use of hydrogen-rich water for irrigation can reduce the use of fertilizers and pesticides, which is conducive to reducing production costs and improving economic benefits.

[0034] KOH is used as an electrolyte, and its concentration directly affects the electrolysis efficiency and hydrogen production. In a preferred embodiment, the mass concentration of the KOH electrolyte is 5-30%. In the above concentration range, the degree of ionization of water molecules is more moderate, which can not only increase the electrolysis speed, but also reduce the energy waste and equipment corrosion caused by excessive concentration. Secondly, the KOH electrolyte within this concentration range has relatively low by-products such as ozone and hypochlorous acid produced during the electrolysis process, so it can significantly reduce the potential harm to crops and improve the safety of agricultural irrigation.

[0035] In a preferred embodiment, the mass concentration of hydrogen-rich water is 1 to 10%. The solubility of hydrogen in water is limited. When the concentration is within the above range, the utilization of hydrogen can be maximized, its biological effectiveness in agricultural irrigation can be improved, and crop growth can be promoted, while avoiding the increase in preparation cost and the decrease in efficiency caused by excessive hydrogen dissolution. Secondly, hydrogen-rich water within this concentration range has obvious benefits to plants, such as antioxidant and stress resistance enhancement, but it does not produce potential biological toxicity or safety risks due to excessive concentration, such as gas release problems caused by hydrogen supersaturation. The method of the present invention can customize irrigation plans according to the needs of different crops by precisely controlling the concentration of hydrogen-rich water, which not only ensures the accurate supply of hydrogen elements, but also reduces resource waste and improves the economic benefits and environmental sustainability of agricultural production.

[0036] To further improve the electrolysis efficiency, in a preferred embodiment, the electrolytic cell includes a cathode electrode, a diaphragm, an anode electrode and a bipolar plate, and the diaphragm is made of polyphenylene sulfide, a proton exchange membrane or yttria-stabilized zirconia. Figure 1 As shown, a plurality of electrode units are supported by a solid screw 1, and a single electrode unit includes a cathode electrode 2, a diaphragm 3, an anode electrode 4 arranged in sequence, and gaskets 5 and bipolar plates 6 on both sides. The KOH electrolyte inlet 7 of the electrolytic cell is located below the KOH electrolyte outlet 8, the H2 outlet 9, and the O2 outlet 10.

[0037] In a preferred embodiment, when the material of the diaphragm is polyphenylene sulfide, the hydrogen production pressure of the electrolyzer is 0.1-3.2 MPa, and the current density is 0.2-0.4 A / cm 2 . The polyphenylene sulfide diaphragm has excellent chemical stability and mechanical strength, can effectively separate the anode and cathode, reduce gas cross-contamination, and ensure the purity of hydrogen. At the same time, within the above pressure range, it can promote the stable operation of the electrolyzer and reduce safety risks under high-pressure conditions. Within the above pressure and current density range, the electrolysis process is both efficient and controllable, which can not only accelerate the production of hydrogen, but also reduce energy consumption and reduce the generation of by-products. For agriculture, a stable supply of hydrogen and the preparation of high-purity hydrogen-rich water can accurately meet the growth needs of crops and improve irrigation effects. At the same time, mild operating conditions can further reduce the potential impact on the agricultural environment and meet environmental protection and sustainable requirements.

[0038] Based on similar reasons, in a preferred embodiment, when the material of the diaphragm is a proton exchange membrane, the hydrogen production pressure of the electrolyzer is 0.1-5.0 MPa, and the current density is 1.0-2.0 A / cm 2 . Due to its high proton conductivity and good gas sealing, the proton exchange membrane can effectively promote the efficiency of electrolysis, prevent hydrogen and oxygen mixing, and significantly improve safety. Within a wide range of hydrogen production pressure, the proton exchange membrane can adapt to the needs of different agricultural scenarios, effectively control the dissolution and transmission of hydrogen, and promote the stable preparation of hydrogen-rich water. Under high current density, the electrolyzer loaded with proton exchange membrane shows high energy conversion rate and hydrogen production rate, which is conducive to accelerating the preparation process of agricultural hydrogen-rich water. The electrolyzer can operate stably under high current, reducing the risk of overheating and equipment damage.

[0039] In a preferred embodiment, when the material of the diaphragm is yttria-stabilized zirconia, the hydrogen production pressure of the electrolyzer is 0.1-1.5 MPa, and the current density is 0.3-1.0 A / cm 2. Yttria-stabilized zirconia (YSZ) diaphragms exhibit excellent proton conductivity and stability at high temperatures, and are suitable for high-temperature working environments for hydrogen production by water electrolysis, which can improve hydrogen production efficiency. The lower hydrogen production pressure range can reduce the pressure requirements for equipment, reduce operating risks, and improve the safety of agricultural applications. At medium current density, yttria-stabilized zirconia electrolyzers can maintain high hydrogen production rates while reducing the increased energy consumption and equipment wear caused by high current density.

[0040] In order to better meet the demand for instant preparation of hydrogen-rich water for agricultural irrigation, in a preferred embodiment, the working temperature of the electrolytic cell is 70-90°C; and / or the volume of the electrolytic cell is 20-50 Nm 3 / h. The increase in operating temperature can accelerate the thermal motion of water molecules and enhance the conductivity of the electrolyte, thereby significantly improving the electrolysis efficiency and accelerating the generation of hydrogen. At the same time, operation within this temperature range also takes into account the thermal stability of the equipment and can reduce safety hazards caused by overheating. The setting of the electrolyzer volume is conducive to a better match between hydrogen generation and agricultural irrigation needs, which can not only meet the irrigation of a large range of farmland, but also reduce the energy waste of excessive hydrogen production and the safety issues of hydrogen storage and transmission.

[0041] In a preferred embodiment, the method further comprises the step of sending the waste liquid of the electrolytic cell into a potash fertilizer preparation system, obtaining potash fertilizer and sending it into an agricultural irrigation area. The recovered potassium hydroxide waste liquid can be reused as potash fertilizer in farmland, so as to achieve more effective utilization of resources and further improve the quality of agricultural products. The potassium hydroxide waste liquid is converted into potash fertilizer after treatment, which can not only effectively solve the problem of waste liquid treatment and reduce potential environmental pollution, but also provide the necessary potassium element for farmland, which is conducive to promoting crop growth and improving the yield and quality of agricultural products. This recycling mechanism can reduce the production cost of potash fertilizer, reduce dependence on chemical synthetic fertilizers, and form a virtuous cycle in the agricultural ecosystem. At the same time, the recycling of waste liquid is also conducive to reducing the waste generated by the operation of the electrolytic cell and improving the safety and environmental protection of the entire system.

[0042] For the purpose of combining agriculture with renewable energy, in a preferred embodiment, the power source of the electrolyzer includes wind power generation and / or photovoltaic power generation. As a renewable clean energy source, wind and solar power have a stable supply and little impact on the environment. They can effectively reduce carbon emissions in the water electrolysis process and improve overall environmental protection. Especially in areas rich in wind and solar resources, the use of these resources for electrolytic hydrogen production can not only reduce dependence on traditional energy and reduce costs, but also help to achieve a continuous supply of electricity and improve the efficiency and continuity of hydrogen-rich water preparation. At the same time, the use of wind and solar power can also reduce the potential safety hazards caused by the combustion of fossil fuels, improve the overall safety of agricultural production, and provide a green, efficient and safe way for the preparation of agricultural hydrogen water, which is conducive to promoting the development of modern agriculture in a low-carbon and sustainable direction.

[0043] The present application is further described in detail below in conjunction with specific embodiments. These embodiments should not be construed as limiting the scope of protection claimed in the present application.

[0044] Example 1

[0045] The flow chart of the method for electrolyzing water to produce hydrogen to improve the quality of agricultural products is shown in Figure 2 .

[0046] Step S1: In areas with abundant wind and agricultural resources, small wind power plants and photovoltaic power plants are built, and the generated electricity is input into the electrolytic cell. Water and KOH in the electrolyte tank are sent to the electrolytic cell, and the KOH electrolyte (mass concentration is 20%) is obtained by mixing in the electrolytic cell, and then sent to the electrolytic cell (working temperature is 80°C, volume is 35Nm 3 / h), power is supplied to carry out electrolysis reaction to obtain hydrogen and oxygen; the waste liquid of the electrolytic cell is sent to the potash fertilizer preparation system, and the obtained potash fertilizer is sent to the agricultural irrigation area;

[0047] Step S2, injecting hydrogen into water through a gas dissolver to saturate the water with hydrogen to obtain hydrogen-rich water (mass concentration of 5%); and sending the hydrogen-rich water to an agricultural irrigation area;

[0048] Step S3, delivering oxygen to the agricultural irrigation area as a nighttime oxygen source;

[0049] Among them, a solution hydrogen concentration sensor is set in the agricultural irrigation area to control the injection volume of the electrolyte tank and the current of the electrolyzer according to the solution hydrogen concentration in the agricultural irrigation area. The material of the diaphragm in the electrolyzer is polyphenylene sulfide, the hydrogen production pressure of the electrolyzer is 1.5MPa, and the current density is 0.3A / cm 2 .

[0050] Example 2

[0051] Step S1: In areas with abundant wind and agricultural resources, small wind power plants and photovoltaic power plants are built, and the generated electricity is input into the electrolytic cell. Water and KOH in the electrolyte tank are sent to the electrolytic cell, mixed in the electrolytic cell to obtain KOH electrolyte (mass concentration of 5%), and sent to the electrolytic cell (working temperature of 90°C, volume of 20Nm 3 / h), power is supplied to carry out electrolysis reaction to obtain hydrogen and oxygen; the power source is wind power generation and photovoltaic power generation, the waste liquid of the electrolytic cell is sent to the potash fertilizer preparation system, and the obtained potash fertilizer is sent to the agricultural irrigation area;

[0052] Step S2, injecting hydrogen into water through a gas dissolver to saturate the water with hydrogen to obtain hydrogen-rich water (mass concentration of 1%); and sending the hydrogen-rich water to an agricultural irrigation area;

[0053] Step S3, delivering oxygen to the agricultural irrigation area as a nighttime oxygen source;

[0054] Among them, a solution hydrogen concentration sensor is set in the agricultural irrigation area to control the injection volume of the electrolyte tank and the current of the electrolyzer according to the solution hydrogen concentration in the agricultural irrigation area. The material of the diaphragm in the electrolyzer is polyphenylene sulfide, the hydrogen production pressure of the electrolyzer is 0.1MPa, and the current density is 0.2A / cm 2 .

[0055] Example 3

[0056] Step S1: In areas with abundant wind and agricultural resources, small wind power plants and photovoltaic power plants are built, and the generated electricity is input into the electrolytic cell. Water and KOH in the electrolyte tank are sent to the electrolytic cell, and the KOH electrolyte (mass concentration is 30%) is obtained by mixing in the electrolytic cell, and then sent to the electrolytic cell (working temperature is 70°C, volume is 50Nm 3 / h), power is supplied to carry out electrolysis reaction to obtain hydrogen and oxygen; the power source is wind power generation and photovoltaic power generation, the waste liquid of the electrolytic cell is sent to the potash fertilizer preparation system, and the obtained potash fertilizer is sent to the agricultural irrigation area;

[0057] Step S2, injecting hydrogen into water through a gas dissolver to saturate the water with hydrogen to obtain hydrogen-rich water (mass concentration of 10%); and sending the hydrogen-rich water to an agricultural irrigation area;

[0058] Step S3, delivering oxygen to the agricultural irrigation area as a nighttime oxygen source;

[0059] Among them, a solution hydrogen concentration sensor is set in the agricultural irrigation area to control the injection volume of the electrolyte tank and the current of the electrolyzer according to the solution hydrogen concentration in the agricultural irrigation area. The material of the diaphragm in the electrolyzer is polyphenylene sulfide, the hydrogen production pressure of the electrolyzer is 3.2MPa, and the current density is 0.4A / cm 2 .

[0060] Example 4

[0061] The difference from Example 1 is that the material of the diaphragm in the electrolyzer is a proton exchange membrane, the hydrogen production pressure of the electrolyzer is 0.1 MPa, and the current density is 1.0 A / cm 2 .

[0062] Example 5

[0063] The difference from Example 1 is that the material of the diaphragm in the electrolyzer is a proton exchange membrane, the hydrogen production pressure of the electrolyzer is 5.0 MPa, and the current density is 2.0 A / cm 2 .

[0064] Example 6

[0065] The difference from Example 1 is that the material of the diaphragm in the electrolytic cell is yttria-stabilized zirconia, the hydrogen production pressure of the electrolytic cell is 0.1 MPa, and the current density is 0.3 A / cm 2 .

[0066] Example 7

[0067] The difference from Example 1 is that the material of the diaphragm in the electrolytic cell is yttria-stabilized zirconia, the hydrogen production pressure of the electrolytic cell is 1.5 MPa, and the current density is 1.0 A / cm 2 .

[0068] As can be seen from the above, each embodiment of the present invention produces hydrogen and prepares hydrogen-rich water by electrolyzing KOH electrolyte, and then applies hydrogen-rich water to agricultural irrigation, and oxygen is used for nighttime oxygen supply to improve the quality of agricultural products. The method of the present invention can also flexibly control the electrolytic hydrogen production process according to the hydrogen concentration of the solution in the agricultural irrigation area, and can take into account both preparation efficiency and safety, and is particularly suitable for areas with good wind and light resources and developed agriculture. The present invention uses electrolytic hydrogen to prepare hydrogen-rich water. The whole process is pollution-free and emission-free, meets environmental protection requirements, and electrolyzed water, as a renewable energy source, has the advantage of sustainable utilization. Compared with traditional agricultural irrigation methods, the use of hydrogen-rich water for irrigation can reduce the use of fertilizers and pesticides, which is conducive to reducing production costs and improving economic benefits.

[0069] In addition, it can be seen that when each process parameter is within the preferred range of the present invention, the overall effect is better.

[0070] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A method for producing hydrogen by electrolysis of water for improving the quality of agricultural products, characterized in that: The following steps are involved: Step S1, feeding water and KOH in the electrolyte tank into an electrolytic cell, mixing to obtain a KOH electrolyte, and applying electricity to perform an electrolytic reaction to obtain hydrogen and oxygen; Step S2, injecting hydrogen into water through a gas dissolver to make the hydrogen in the water reach a saturated or supersaturated state to obtain hydrogen-rich water, and sending the hydrogen-rich water to an agricultural irrigation area; Step S3, delivering oxygen into the agricultural irrigation area as a nighttime oxygen source; Wherein, a solution hydrogen concentration sensor is arranged in the agricultural irrigation area to control the KOH injection amount of the electrolyte tank according to the solution hydrogen concentration in the agricultural irrigation area.

2. The method according to claim 1, characterized in that The mass concentration of the KOH electrolyte is 5-30%.

3. The method according to claim 1 or 2, characterized in that: The mass concentration of the hydrogen-rich water is 1-10%.

4. The method according to any one of claims 1 to 3, characterized in that The electrolytic cell comprises a cathode electrode, a diaphragm, an anode electrode and a bipolar plate. The material of the diaphragm is polyphenylene sulfide, a proton exchange membrane or yttria-stabilized zirconia.

5. The method according to claim 4, characterized in that When the material of the diaphragm is polyphenylene sulfide, the hydrogen production pressure of the electrolytic cell is 0.1-3.2 MPa, and the current density is 0.2-0.4 A / cm 2 .

6. The method according to claim 4, characterized in that When the material of the diaphragm is the proton exchange membrane, the hydrogen production pressure of the electrolyzer is 0.1-5.0 MPa, and the current density is 1.0-2.0 A / cm 2 .

7. The method according to claim 4, characterized in that When the material of the diaphragm is the yttria-stabilized zirconia, the hydrogen production pressure of the electrolytic cell is 0.1-1.5 MPa, and the current density is 0.3-1.0 A / cm 2 .

8. The method according to any one of claims 1 to 7, characterized in that The working temperature of the electrolytic cell is 70-90°C; and / or the volume of the electrolytic cell is 20-50Nm 3 / h.

9. The method according to any one of claims 1 to 8, characterized in that The method also includes the step of sending the waste liquid from the electrolytic cell into a potash fertilizer preparation system to obtain potash fertilizer and sending it to the agricultural irrigation area.

10. The method according to any one of claims 1 to 9, characterized in that The power source of the electrolyzer includes wind power generation and / or photovoltaic power generation.

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