A fruit and vegetable ripening system

Abstract

The present application belongs to the technical field of fruit and vegetable ripening technology, and relates to a ripening system for various fruits and vegetables. The fruit and vegetable ripening system developed by the present application can convert inexpensive and readily available raw materials into ethylene, thereby realizing the ripening of fruits and vegetables. The device has a simple structure and is easy to scale. The device is driven by electric energy, has low energy consumption, a wide source of raw materials, a low price, a green and safe operation process, and good fruit and vegetable ripening effect.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of fruit and vegetable ripening, in particular to a ripening system for various fruits and vegetables. BACKGROUND

[0002] With the continuous improvement of living standards in China, people pay more attention to the freshness and nutritional value of fruits and vegetables, and put forward higher and higher requirements for the edible quality of fruits and vegetables. Post-ripening fruits and vegetables are usually picked and transported at a low degree of maturity, but at this time their hardness is high and they cannot be eaten. Therefore, it is of practical significance and important market value to ripen post-ripening fruits and vegetables.

[0003] Ethylene is a common hormone for plant growth and maturity. The commonly used ripening methods mainly include ethephon and ethylene gas ripening method. Ethylene is sprayed on the surface of fruits and vegetables to release ethylene to promote the ripening of fruits and vegetables, but it is easy to remain on the surface of fruits and vegetables, which is harmful to human health. In addition, the production of ethephon has high energy consumption and causes environmental pollution. For the ethylene gas ripening method, ethylene gas is introduced into a closed ripening room, and fruits and vegetables are placed in the ripening room to realize ripening. The source of ethylene gas on the market is usually an ethylene generator, which converts ethanol into ethylene by using the principle of thermal catalysis. This method has high requirements for the purity of raw materials, the process is complex and the cost is high. In terms of technology, the current ethylene generator has low conversion rate and cannot be used for a long time. Therefore, it is of great significance to develop a new ripening technology for the storage and transportation of fruits and vegetables. SUMMARY

[0004] In view of the problems and deficiencies of the prior art, the present application aims to provide a new ripening system which can realize the ripening effect of fruits and vegetables at low cost and low energy consumption according to actual needs.

[0005] The specific technical scheme of the present application is as follows: a fruit and vegetable ripening system, comprising a power supply system, a gas generation chamber, a gas absorption module and a fruit and vegetable storage chamber, and / or a gas separation module. The use steps of the system are as follows:

[0006] Firstly, place the fruits and vegetables to be ripened in the fruit and vegetable storage chamber;

[0007] Secondly, input raw materials into the gas generation chamber;

[0008] Thirdly, turn on the power supply system, and the gas generation chamber generates ethylene under the drive of electricity and delivers the ethylene to the fruit and vegetable storage chamber to start ripening.

[0009] Fourthly, cut off the power supply when the ripening process is completed.

[0010] The power supply system comprises fire power generation, photovoltaic power generation, hydroelectric power generation, etc.

[0011] The gas generating chamber includes an electrolysis module and a liquid storage module. The electrolysis module includes an anode, a cathode, a separator, a current collector or a flow channel plate, wherein the anode part and the cathode part are separated by the separator. The separator includes but is not limited to a cation exchange membrane, an anion exchange membrane, a bipolar membrane, a salt bridge, an asbestos net and the like. The electrolysis module can include an electrolytic cell for converting carbon dioxide into carbon monoxide. The liquid storage module includes a first liquid storage tank for supplying anode electrolyte and a second liquid storage tank for supplying cathode electrolyte. The electrolyte used in the electrolysis includes cations and anions, but the cations and anions do not necessarily form a salt, including but not limited to bicarbonate, carbonate, sodium hydroxide, potassium hydroxide, sulfuric acid and the like. When the gas generating chamber is working, the electrolyte can enter the anode and the cathode respectively under the driving of the circulating pump. When the system works for a certain period of time, the system can prompt to replace the electrolyte, and the replaced electrolyte can be used as the absorbent of the absorption module.

[0012] The raw materials used in the gas generating chamber include carbon dioxide or chemicals that can release carbon dioxide, including but not limited to one or more of bicarbonate, carbonate, citric acid.

[0013] The working principle of the gas generating chamber is that carbon dioxide is reduced to ethylene under the driving of electricity, and the specific reaction equation is: 2CO2+ 2H2O = C2H4+3O2.

[0014] The gas absorption module of the system mainly consists of an absorbent and a storage, and is connected with the gas generating chamber and the fruit and vegetable storage chamber. The absorbent is a chemical that can absorb carbon dioxide, including one or more of sodium hydroxide, potassium hydroxide, cesium hydroxide, organic amine and porous material, and the absorbent is designed to receive the unreacted carbon dioxide in the gas product generated by the gas generating chamber and the carbon dioxide released during the ripening of fruits and vegetables. The absorbent can be used as a raw material in the gas generating chamber after being used for a period of time, and the system can prompt to replace the absorbent after electrolysis for a certain time under a certain current density. The saturated absorbent can be used as the electrolyte in the electrolysis module, which can further reduce the raw material cost of the system while improving the carbon dioxide conversion rate.

[0015] The system can have a gas separation module connected with the exhaust port of the gas absorption module to separate hydrogen, ethylene and the like in the gas generating chamber. The separated gas can be stored in a first gas storage tank and a second gas storage tank or directly delivered to the fruit and vegetable storage chamber. The separation method includes one or a combination of more than one of cold box, separation membrane, hydrogen adsorbing material and the like. The separated hydrogen can be used for fruit and vegetable preservation.

[0016] The fruit and vegetable storage chamber includes, but is not limited to, a goods warehouse, a fruit and vegetable storage cabinet, a refrigerator, a ripening vehicle, a ripening box and a ripening container, and a household ripening and fresh-keeping integrated machine. The fruit and vegetable storage chamber can include a detection device; the detection device is placed inside the storage chamber to detect the content parameters of carbon dioxide, ethylene, water vapor, hydrogen and / or temperature parameters in the chamber body, so as to judge the ripening condition of the fruit and vegetable.

[0017] When the carbon dioxide concentration in the fruit and vegetable storage chamber reaches a high concentration, the ventilation valve of the fruit and vegetable storage chamber is opened and the indoor gas flows to the gas absorption module, so as to realize the purpose of reducing the carbon dioxide concentration in the chamber. While avoiding the damage of too high carbon dioxide concentration to the fruit and vegetable, the carbon dioxide can be reconverted into raw materials for the gas generation chamber.

[0018] The fruit and vegetable storage chamber can have an image acquisition unit for identifying the fruit and vegetable image in the fruit and vegetable ripening chamber, determining the preset ripening degree of the fruit and vegetable in the fruit and vegetable ripening chamber according to the fruit and vegetable image, and judging whether the fruit and vegetable needs to continue to ripen according to the preset ripening degree. If the fruit and vegetable needs to continue to ripen, the fruit and vegetable is ripened by selecting the ripening mode corresponding to the preset ripening degree. Further, the controller determines the preset ripening degree of the fruit and vegetable according to the fruit and vegetable image, and the specific process can include: determining the preset fruit and vegetable type corresponding to the fruit and vegetable according to the shape of the fruit and vegetable in the fruit and vegetable image; and determining the preset ripening degree required by the corresponding fruit and vegetable according to the color of the fruit and vegetable in the fruit and vegetable image.

[0019] The system can be provided with an automatic control subsystem, which can control the release of ripening gas in the gas generation chamber according to the concentration of gas in the fruit and vegetable storage chamber. When the ethylene concentration in the fruit and vegetable storage chamber is high to the alarm value, the power supply will automatically reduce or stop the current to reduce or stop the production of ethylene in the gas generation chamber. When the ethylene concentration in the fruit and vegetable storage chamber is lower than the set value, the power supply will increase the corresponding current to increase the production rate of ethylene in the gas generation chamber. In addition, the system can adjust the ratio of ethylene and hydrogen release by changing the cell voltage of the electrolytic cell according to the actual demand.

[0020] Compared with the prior art, the advantages of the present application are: the device structure is simple and easy to scale, driven by electric energy and using carbon dioxide as raw material, with low energy consumption, wide raw material sources, low price, green and safe operation process, and good fruit and vegetable ripening effect. BRIEF DESCRIPTION OF DRAWINGS

[0021] Figure 1 is a schematic diagram of the ripening and preservation integrated device. Wherein: 1-1 power supply system, 1-2 gas generation chamber, 1-3 gas absorption module, 1-5 fruit and vegetable storage chamber, 1-6 automatic control subsystem, 1-7 power supply, 1-8 wire, 1-9 current collector, 1-10 flow channel plate, 1-11 anode electrode, 1-12 separator, 1-13 cathode electrode, 1-14 first liquid storage tank, 1-15 circulating pump, 1-16 second liquid storage tank, 1-17 anode gas discharge port, 1-18 absorbent, 1-19 gas separation module, 1-20 first gas storage tank, 1-21 second gas storage tank, 1-22 concentration detector, 1-23 computer.

[0022] Figure 2 is a schematic diagram of the ripening and preservation integrated device according to embodiment 4. Wherein: 2-1 power supply system, 2-2 gas generation chamber, 2-3 gas absorption module, 2-5 fruit and vegetable storage chamber, 2-6 automatic control subsystem, 2-7 power supply, 2-8 wire, 2-9 current collector, 2-10 flow channel plate, 2-11 anode electrode, 2-12 separator, 2-13 cathode electrode, 2-14 first liquid storage tank, 2-15 circulating pump, 2-16 second liquid storage tank, 2-17 carbon dioxide cylinder, 2-18 anode gas discharge port, 2-19 one-way valve, 2-20 absorbent, 2-21 gas separation module, 2-22 first gas storage tank, 2-23 second gas storage tank, 2-24 concentration detector, 2-25 computer.

[0023] Figure 3 is a schematic diagram of the ripening device according to embodiment 5. Wherein: 3-1 power supply system, 3-2 gas generation chamber, 3-3 gas absorption module, 3-4 fruit and vegetable storage chamber, 3-5 automatic control subsystem, 3-6 power supply, 3-7 wire, 3-8 current collector, 3-9 flow channel plate, 3-10 anode electrode, 3-11 separator, 3-12 cathode electrode, 3-13 first liquid storage tank, 3-14 circulating pump, 3-15 second liquid storage tank, 3-16 carbon dioxide cylinder, 3-17 anode gas discharge port, 3-18 one-way valve, 3-19 absorbent, 3-20 concentration detector, 3-21 computer.

[0024] Figure 4 is a schematic diagram of the ripening and preservation integrated device according to embodiment 8 of the present application. Wherein: 4-1 power supply system, 4-2 gas generation chamber, 4-3 gas absorption module, 4-5 fruit and vegetable storage chamber, 4-6 automatic control subsystem, 4-7 power supply, 4-8 wire, 4-9 first liquid storage tank, 4-10 anode electrode, 4-11 second liquid storage tank, 4-12 separator, 4-13 cathode electrode, 4-14 carbon dioxide gas generation chamber cavity, 4-15 heater, 4-16 one-way valve, 4-17 anode gas discharge port, 4-18 absorbent, 4-19 gas separation module, 4-20 first gas storage tank, 4-21 second gas storage tank, 4-22 concentration detector, 4-23 computer.

[0025] Figure 5 is a schematic diagram of the ripening and preservation integrated device according to embodiment 9 of the present application. Wherein: 5-1 power supply system, 5-2 gas generation chamber, 5-3 gas absorption module, 5-5 fruit and vegetable storage chamber, 5-6 automatic control subsystem, 5-7 power supply, 5-8 wire, 5-9 flow channel plate, 5-10 current collector, 5-11 anode electrode, 5-12 separator, 5-13 cathode electrode, 5-14 first liquid storage tank, 5-15 circulating pump, 5-16 second liquid storage tank, 5-17 foam box, 5-18 anode gas discharge port, 5-19 one-way valve, 5-20 absorbent, 5-21 gas separation module, 5-22 first gas storage tank, 5-23 second gas storage tank, 5-24 concentration detector, 5-25 computer.

[0026] Figure 6 is a schematic diagram of the ripening and preservation integrated device according to embodiment 10 of the present application. Wherein: 6-1 power supply system, 6-2 gas generation chamber, 6-3 gas absorption module, 6-5 fruit and vegetable storage chamber, 6-6 automatic control subsystem, 6-7 power supply, 6-8 wire, 6-9 carbon dioxide gas cylinder, 6-10 first electrolytic cell, 6-11 second electrolytic cell, 6-12 flow channel plate, 6-13 current collector, 6-14 anode electrode, 6-15 separator, 6-16 cathode electrode, 6-17 first liquid storage tank, 6-18 circulating pump, 6-20 absorbent, 6-21 gas separation module, 6-22 first gas storage tank, 6-23 second gas storage tank, 6-24 concentration detector, 6-25 computer. DETAILED DESCRIPTION

[0027] In order to make the technical problems to be solved by the present application, technical solutions and beneficial effects more clearly, the present application will be further described in detail below in combination with the drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and not to limit the present application.

[0028] Embodiment 1:

[0029] The power supply system adopts direct current power supply, the gas generation chamber adopts a bipolar plate with a serpentine flow channel as a flow channel plate and a current collector, a bipolar membrane is used as a separator to divide the electrolytic device into a cathode chamber and an anode chamber, a first liquid storage tank is 1 mol / L sodium hydroxide solution, and a second liquid storage tank is 3 mol / L sodium bicarbonate aqueous solution; carbon paper sprayed with copper oxide catalyst is used as a cathode, and a titanium mesh deposited with IrOx is used as an anode, wherein the size of the carbon paper and the titanium mesh is 2 cm x 2 cm. The flow rates of the cathode and anode electrolytes are both controlled to be 40 mL / min. The direct current power supply is turned on, and the current density of the constant current electrolysis is controlled to be 50 mA / cm 2 , 100 mA / cm 2 , 150 mA / cm 2 , 200 mA / cm 2 , respectively, and the electrolysis time under each current density is one hour. In the cathode, bicarbonate ions combine with hydrogen ions to generate carbon dioxide, and the carbon dioxide obtains electrons on the cathode to generate ethylene. The generated gas is introduced into an absorption module, and the absorption agent used is 3 mol / L sodium hydroxide solution. The gas outlet of the absorption module is connected to a gas separation module, and in this embodiment, the separation module uses a hydrogen separation membrane to separate ethylene and hydrogen. The ethylene and hydrogen outlets of the gas separation module are respectively connected to a ripening box and a preservation box, and five fruits of the same kind are placed in each box. The ripening fruits used include unripe bananas, mangoes, kiwis, papayas and lemons, and the preservation fruits used include strawberries, lychees, ripe kiwis, grapes and cherries. The gas concentration of ethylene and hydrogen is detected by a gas detection module; the time when the absorption agent in the absorption module is completely converted into sodium bicarbonate is calculated by the current and time of electrolysis through a timing module, and when the absorption agent sodium hydroxide is completely converted into sodium bicarbonate, it is placed in the second liquid storage tank and used as a cathode electrolyte.

[0030] Table 1 is the product selectivity and gas concentration of ethylene and hydrogen generated by electrochemical reduction of CO2 under different current densities in the system of Example 1.

[0031]

[0032] Table 2 is the ripening time of different fruits in the ripening box under different current densities in Example 1.

[0033]

[0034] Table 3 is the preservation time of different fruits in the preservation box under different current densities in Example 1.

[0035] Example 1 Current density Strawberry Litchi Ripe kiwifruit Grape Cherry 50 mA / cm 2 ]] 2.0 days 2.1 days 4.0 days 3.8 days 2.9 days 100 mA / cm 2 ]] 4.2 days 3.1 days 5.2 days 4.6 days 4.5 days 150 mA / cm 2 ]] 6.2 days 4.0 days 9.0 days 6.5 days 6.3 days 200 mA / cm 2 ]] 7.0 days 4.8 days 9.7 days 7.2 days 7.5 days Example 2:

[0036] The power supply system adopts direct current power supply, the gas generation chamber adopts a bipolar plate with a serpentine flow channel as a flow channel plate and a current collector, and an anion exchange membrane is used as a separator to divide the electrolytic device into a cathode chamber and an anode chamber. The first liquid storage tank is 3 mol / L sodium hydroxide solution, and the second liquid storage tank is 3 mol / L sodium bicarbonate aqueous solution. Carbon paper sprayed with copper oxide catalyst is used as the cathode, and titanium mesh deposited with IrOx is used as the anode. The size of the carbon paper and the titanium mesh is 2 cm x 2 cm. The flow rate of the cathode and anode electrolyte is controlled to be 40 mL / min. The direct current power supply is turned on, and the current density of the constant current electrolysis is controlled to be 50 mA / cm 2 , 100 mA / cm 2 , 150 mA / cm 2 , 200 mA / cm 2 , respectively. The electrolysis time is one hour under each current density. At the cathode, bicarbonate ions combine with hydrogen ions to form carbon dioxide, which is reduced at the cathode to form ethylene. The gas generated above is introduced into the absorption module, and the absorption agent used is 3 mol / L sodium hydroxide solution. The gas outlet of the absorption module is connected to the gas separation module. In this embodiment, the separation module uses a hydrogen separation membrane to separate ethylene and hydrogen. The ethylene and hydrogen outlets of the gas separation module are connected to the ripening box and the preservation box, respectively, and five fruits of the same kind are placed in each box. The ripening fruits used include unripe bananas, mangoes, kiwis, papayas and lemons; the preservation fruits used include strawberries, lychees, ripe kiwis, grapes and cherries.

[0037] Table 4 is the selectivity and gas concentration of ethylene and hydrogen generated by electrochemical reduction of CO2 in the gas generation chamber under different current densities in Example 2.

[0038]

[0039] Table 5 is the ripening time of different fruits in the ripening box under different current densities in Example 2.

[0040]

[0041] Table 6 is the preservation time of different fruits in the preservation box under different current densities in Example 2.

[0042]

[0043] Example 3:

[0044] The power supply system uses photovoltaic cell panel. The gas generation chamber uses a bipolar plate with a serpentine flow channel as the flow channel plate and current collector. An anion exchange membrane is used as a separator to divide the electrolytic device into a cathode chamber and an anode chamber. The first storage tank is 2 mol / L sodium hydroxide solution, and the second storage tank is 2 mol / L sodium bicarbonate solution saturated with carbon dioxide. Carbon paper sprayed with copper oxide catalyst is used as the cathode, and IrOx-deposited titanium mesh is used as the anode. The size of the carbon paper and titanium mesh is 2 cm x 2 cm. The flow rate of the cathode and anode electrolyte is controlled at 100 mL / min. The power is turned on, and the current density of the constant current electrolysis is controlled at 50 mA / cm 2 , 100 mA / cm 2 , 150 mA / cm 2 , 200 mA / cm 2 , respectively. The electrolysis time is one hour at each current density. The gas generated above is introduced into the absorption module, and the absorbent used is 3 mol / L sodium hydroxide solution. The outlet of the absorption module is connected to the ripening box, and five fruits of the same kind are placed in each box. The ripening fruits used include unripe bananas, mangoes, kiwis, papayas, and lemons.

[0045] Table 7 is the selectivity and gas concentration of ethylene and hydrogen generated by electrochemical reduction of CO2 in the gas generation chamber at different current densities in Example 3.

[0046]

[0047] Table 8 is the ripening time of different fruits in the ripening box at different current densities in Example 3.

[0048]

[0049] Example 4:

[0050] The power supply system uses photovoltaic cell panel. The gas generation chamber uses a bipolar plate with a serpentine flow channel as the flow channel plate and current collector. An anion exchange membrane is used as a separator to divide the electrolytic device into a cathode chamber and an anode chamber. The first storage tank is 2 mol / L sodium hydroxide solution, and the second storage tank is 2 mol / L sodium bicarbonate solution saturated with carbon dioxide. Carbon paper sprayed with copper oxide catalyst is used as the cathode, and IrOx-deposited titanium mesh is used as the anode. The size of the carbon paper and titanium mesh is 2 cm x 2 cm. The flow rate of the cathode and anode electrolyte is controlled at 100 mL / min. The power is turned on, and the current density of the constant current electrolysis is controlled at 50 mA cm 2 , 100 mA / cm 2 , 150 mA / cm 2 , 200 mA / cm 2The electrolysis time was one hour at each current density. The gas generated above was introduced into the absorption module, and the absorption agent used was 3 mol / L sodium hydroxide solution. The gas outlet of the absorption module was connected to the gas separation module, and in this embodiment, the separation module used a hydrogen separation membrane to separate ethylene and hydrogen. The ethylene and hydrogen outlets of the gas separation module were connected to the ripening box and the preservation box, respectively, and five fruits of the same kind were placed in each box. The ripening fruits used included unripe bananas, mangoes, kiwifruits, papayas and lemons; and the preservation fruits used included strawberries, lychees, ripe kiwifruits, grapes and cherries.

[0051] Table 9 is the selectivity and gas concentration of ethylene and hydrogen generated by electrochemical reduction of CO2 at different current densities in the gas generation chamber in Example 4.

[0052]

[0053] Table 10 is the ripening time of different fruits in the ripening box at different current densities in Example 4.

[0054] Example 4 Current density Banana Mango Kiwifruit Papaya Lemon 50 mA / cm 2 ]] 3.5 days 3.2 days 4.2 days 3.1 days 4.8 days 100 mA / cm 2 ]] 2.8 days 2.6 days 3.3 days 2.3 days 3.9 days 150 mA / cm 2 ]] 1.9 days 1.8 days 2.4 days 1.6 days 2.4 days 200 mA / cm 2 ]]> 1.1 days 0.6 days 1.6 days 0.8 days 1.9 days

[0055] Table 11 is the preservation time of different fruits in the preservation box at different current densities in Example 4.

[0056] Example 4 Current density Strawberry Litchi Ripe kiwifruit Grape Cherry 50 mA / cm 2 ]] 2.1 days 2.2 days 4.0 days 3.8 days 2.9 days 100 mA / cm 2 ]] 4.3 days 3.2 days 5.2 days 4.7 days 4.6 days 150 mA / cm 2 ]] 6.3 days 4.1 days 9.0 days 6.5 days 6.4 days 200 mA / cm 2 ]]> 7.2 days 5.0 days 9.9 days 7.4 days 7.7 days

[0057] Example 5:

[0058] The power supply system used a photovoltaic cell panel, the gas generation chamber used a bipolar plate with a serpentine flow channel as the flow channel plate and current collector, and an anion exchange membrane was used as the separator to divide the electrolysis device into a cathode chamber and an anode chamber. The first liquid tank contained 1 mol / L potassium bicarbonate solution, and there was a liquid chamber between the cathode and the separator to store a small amount of cathode electrolyte. Carbon dioxide gas was used as the raw material and was delivered to the cathode. There was a liquid chamber between the anode and the separator to store a small amount of anode electrolyte. Carbon paper sprayed with copper oxide catalyst was used as the cathode, and IrOx-deposited titanium mesh was used as the anode, and the size of the carbon paper and titanium mesh was 2 cm x 2 cm. The cathode gas flow rate was controlled to be 20 mL / min, and the anode electrolyte flow rate was 50 mL / min. The power was turned on, and the current density of the constant current electrolysis was controlled to be 50 mA / cm 2 , 100 mA / cm 2 , 150 mA / cm 2 , 200 mA / cm 2electrolysis time for each current density is 30 minutes. The carbon dioxide is reduced on the cathode to generate ethylene. The generated gas is passed into the absorption module, and the absorption agent used is 3 mol / L sodium hydroxide solution. The outlet of the absorption module is connected to the ripening box, and five fruits of the same kind are placed in each box. The ripening fruits used include unripe bananas, mangoes, kiwifruits, papayas, and lemons.

[0059] Table 12 is the gas selectivity and corresponding concentration of ethylene and hydrogen generated by electrochemical reduction of CO2 at different current densities in the gas generation chamber in Example 5.

[0060] Example 5 Current density Ethylene selectivity Ethylene concentration Hydrogen selectivity Hydrogen concentration 50 mA / cm 2 ]] 11.2% 387 ppm 44.6% 3122 ppm 100 mA / cm 2 ]] 22.4% 1524 ppm 39.4% 5122 ppm 150 mA / cm 2 ]] 25.8% 2709 ppm 37.3% 7833 ppm 200 mA / cm 2 ]] 35.1% 4914 ppm 41.8% 11704 ppm

[0061] Table 13 is the ripening time of different fruits in the ripening box at different current densities in Example 5

[0062] Example 5 Current density Banana Mango Kiwifruit Papaya Lemon 50 mA / cm 2 ]] 3.8 days 3.2 days 5.0 days 3.6 days 5.3 days 100 mA / cm 2 ]] 2.1 days 1.8 days 3.0 days 1.6 days 3.2 days 150 mA / cm 2 ]] 1.4 days 1.2 days 2.0 days 1.3 days 2.6 days 200 mA / cm 2 ]] 0.5 days 0.6 days 1.2 days 0.9 days 1.0 days Example 6:

[0063] The power supply system uses a photovoltaic cell panel, and a Peek plate with channels is used as the flow channel plate in the gas generation chamber. Copper wires are used as the current collector, and an asbestos net is used as the separator to divide the electrolytic device into a cathode chamber and an anode chamber. The first storage tank is 1 mol / L potassium hydroxide solution, and the second storage tank is 1 mol / L potassium hydroxide solution. Carbon dioxide gas is used as the raw material and is delivered to the cathode gas chamber. Carbon paper sprayed with nano copper powder is used as the cathode, and nickel foam is used as the anode. The size of the carbon paper and the titanium mesh is 2 cm x 2 cm. The control cathode gas flow rate is 20 mL / min, and the anode electrolyte flow rate is 50 mL / min. The power is turned on, and the current density of the constant current electrolysis is controlled at 50 mA / cm 2 , 100 mA / cm 2 , 150 mA / cm 2 , and 200 mA / cm 2 , respectively. The electrolysis time for each current density is 30 minutes. The generated gas is passed into the absorption module, and the absorption agent used is 3 mol / L sodium hydroxide solution. The outlet of the absorption module is connected to the ripening box, and five fruits of the same kind are placed in each box. The ripening fruits used include unripe bananas, mangoes, kiwifruits, papayas, and lemons.

[0064] Table 14 is the selectivity and gas concentration of ethylene and hydrogen generated by electrochemical reduction of CO2 at different current densities in the gas generation chamber in Example 6.

[0065] Example 6 Current density Ethylene selectivity Ethylene concentration Hydrogen selectivity Hydrogen concentration 50 mA / cm 2 ]] 13.0% 455 ppm 40.6% 2639 ppm 100 mA / cm 2 ]] 21.5% 1505 ppm 36.3% 4719 ppm 150 mA / cm 2 ]] 30.8% 3234 ppm 33.2% 6474 ppm 200 mA / cm 2 ]]> 40.1% 5614 ppm 26.5% 6890 ppm

[0066] Table 15 is the ripening time of different fruits in the ripening box under different current densities in Example 6

[0067] Example 6 Current density Banana Mango Kiwifruit Papaya Lemon 50 mA / cm 2 ]]> 3.5 days 3.1 days 4.4 days 3.3 days 4.8 days 100 mA / cm 2 ]] 2.0 days 1.6 days 2.9 days 1.7 days 2.9 days 150 mA / cm 2 ]] 0.7 days 0.9 days 1.6 days 0.9 days 1.9 days 200 mA / cm 2 ]] 0.5 days 0.7 days 1.3 days 0.7 days 1.2 days

[0068] Example 7:

[0069] The power supply system adopts a photovoltaic cell panel, a Peek plate with channels is used as a flow channel plate in the gas generation chamber, copper wires are used as current collectors, and a cation exchange membrane is used to divide the electrolytic device into a cathode chamber and an anode chamber. The gas chamber is connected to CO2 gas, the first liquid tank is 0.05 mol / L sulfuric acid solution, and the second liquid tank is 0.05 mol / L sulfuric acid solution plus 2 mol / L potassium chloride. Carbon paper sprayed with copper oxide catalyst is used as the cathode, and titanium mesh deposited with IrOx is used as the anode. The size of the carbon paper and the titanium mesh is both 2 cm × 2 cm. The flow rate of the cathode and anode electrolyte is controlled to be 100 mL / min. The power is turned on, and the current density of the constant current electrolysis is controlled to be 50 mA / cm 2 , 100 mA / cm 2 , 150 mA / cm 2 , 200 mA / cm 2 , respectively. The electrolysis time under each current density is 30 minutes. The gas generated above is connected to the separation module. In this embodiment, the separation module uses a hydrogen separation membrane to separate ethylene and hydrogen. The ethylene and hydrogen outlets of the gas separation module are connected to the ripening box and the preservation box, respectively, and five fruits of the same kind are placed in each box. The fruits used for ripening include unripe bananas, mangoes, kiwis, papayas, and lemons, and the fruits used for preservation include strawberries, lychees, ripened kiwis, grapes, and cherries.

[0070] Table 16 is the selectivity and gas concentration of ethylene and hydrogen generated by electrochemical reduction of CO2 in the gas generation chamber under different current densities in Example 7.

[0071] Example 7 Current density Ethylene selectivity Ethylene concentration Hydrogen selectivity Hydrogen concentration 50 mA / cm 2 ]] 21.0% 735 ppm 64.6% 4199 ppm 100 mA / cm 2 ]] 31.5% 2205 ppm 59.3% 7709 ppm 150 mA / cm 2 ]] 38.8% 4074 ppm 47.2% 9204 ppm 200 mA / cm 2 ]]> 42.1% 5894 ppm 51.5% 13390 ppm

[0072] Table 17 is the ripening time of different fruits in the ripening box under different current densities in Example 7

[0073] Example 7 Current density Banana Mango Kiwifruit Papaya Lemon 50 mA / cm 2 ]] 2.8 days 2.4 days 3.4 days 2.3 days 3.9 days 100 mA / cm 2 ]] 1.2 days 1.1 days 1.9 days 1.0 days 2.4 days 150 mA / cm 2 ]] 0.4 days 0.6 days 1.3 days 0.7 days 0.9 days 200 mA / cm 2 ]] 0.2 days 0.2 days 0.7 days 0.3 days 0.3 days

[0074] Table 18 is the preservation time of different fruits in the preservation box under different current densities in Example 7

[0075] Example 7 Current density Strawberry Litchi Ripe kiwifruit Grape Cherry 50 mA / cm 2 ]]> 2.0 days 2.1 days 3.9 days 3.7 days 2.8 days 100 mA / cm 2 ]]> 4.3 days 3.3 days 5.3 days 4.8 days 4.6 days 150 mA / cm 2 ]]> 5.9 days 3.8 days 6.7 days 5.6 days 5.6 days 200 mA / cm 2 ]]> 7.0 days 5.3 days 11.3 days 8.5 days 8.2 days

[0076] Example 8:

[0077] The power supply system uses a direct current power supply, and the asbestos net is used as a separator to connect the first liquid storage tank and the second liquid storage tank together in the gas generation chamber. The first liquid storage tank is 0.5 mol / L sodium bicarbonate solution, and the second liquid storage tank is 0.5 mol / L sodium bicarbonate solution. The carbon paper sprayed with copper powder catalyst is used as the cathode, and the iron oxyhydroxide loaded on the nickel foam is used as the anode. The size of the carbon paper and the titanium mesh is 2 cm x 2 cm. The top of the second liquid storage tank is provided with a gas inlet and a gas outlet, and the gas inlet is connected with the gas outlet of the carbon dioxide generating device. The carbon dioxide generating device is composed of a cavity and a heating table, and the top end of the cavity is provided with a gas outlet and a one-way valve. The sodium bicarbonate is placed on the heating table. The heating temperature is set to 60°C, and the device will release carbon dioxide into the gas generation chamber. The direct current power supply is turned on, and the current density of the constant current electrolysis is 30 mA / cm 2 , 50 mA / cm 2 , 70 mA / cm 2 , 100 mA / cm 2 , respectively. The electrolysis time under each current density is 30 minutes. The above generated gas is introduced into the separation module. In this embodiment, the separation module uses a hydrogen separation membrane to separate ethylene and hydrogen. The ethylene and hydrogen outlets of the gas separation module are connected with the ripening boxes and the preservation boxes, respectively, and five fruits of the same kind are placed in each box. The ripening fruits used include unripe bananas, mangoes, kiwis, papayas and lemons, and the preservation fruits used include strawberries, lychees, ripe kiwis, grapes and cherries.

[0078] Table 19 is the selectivity and gas concentration of ethylene and hydrogen generated by electrochemical reduction of CO2 in the gas generation chamber under different current densities in Example 8.

[0079] Example 8 Current density Ethylene selectivity Ethylene concentration Hydrogen selectivity Hydrogen concentration 30 mA / cm 2 ]] 21.0% 441 ppm 44.6% 1873 ppm 50 mA / cm 2 ]] 38.2% 1337 ppm 20.3% 1421 ppm 70 mA / cm 2 ]] 25.6% 1254 ppm 46.2% 4527 ppm 100 mA / cm 2 ]] 17.1% 1197 ppm 59.8% 8372 ppm

[0080] Table 20 is the ripening time of different fruits in the ripening box under different current densities in Example 8.

[0081] Example 8 Current density Banana Mango Kiwi Papaya Lemon 30 mA / cm 2 ]] 3.0 days 2.5 days 4.1 days 2.8 days 4.6 days 50 mA / cm 2 ]] 1.9 days 1.8 days 2.3 days 1.6 days 2.5 days 70 mA / cm 2 ]] 2.0 days 1.9 days 2.5 days 1.7 days 2.6 days 100 mA / cm 2 ]] 2.1 days 2.0 days 2.6 days 1.7 days 2.7 days

[0082] Table 21 is the preservation time of different fruits in the preservation box under different current densities in Example 8.

[0083] Example 8 Current density Strawberry Litchi Ripening kiwi Grape Cherry 30 mA / cm 2 ]] 1.3 days 1.4 days 2.6 days 2.1 days 2.0 days 50 mA / cm 2 ]]> 1.2 days 1.3 days 2.4 days 2.0 days 1.8 days 70 mA / cm 2 ]] 2.1 days 2.2 days 3.9 days 4.0 days 3.0 days 100 mA / cm 2 ]]> 4.4 days 3.5 days 5.4 days 4.9 days 4.9 days

[0084] Example 9:

[0085] The power supply system adopts direct current power supply, and the gas generating chamber adopts a bipolar plate with a serpentine flow channel as a flow channel plate and a current collector. A salt bridge is used as a separator to divide the electrolytic device into a cathode chamber and an anode chamber. The first liquid storage tank is 1 mol / L sodium bicarbonate solution, and the second liquid storage tank is pure water, wherein the first liquid storage tank is connected with the anode chamber and the salt bridge chamber, and the second liquid storage tank is connected with the cathode chamber. The copper particle catalyst deposited in situ on the carbon paper is used as the cathode, and the nickel foam is used as the anode, wherein the size of the carbon paper and the nickel foam is 2 cm × 2 cm. The liquid in the first liquid storage tank flows into the anode chamber and the cathode chamber through two circulating pumps, and the flow rate of the first liquid storage tank is controlled at 150 mL / min. The top of the second liquid storage tank is provided with a gas inlet and a gas outlet, wherein the gas inlet is connected with a carbon dioxide generating device, and the gas outlet is connected with the cathode chamber. The carbon dioxide generating device is a foam box with a gas outlet at the top, and a whole piece of dry ice is placed in the foam box. At the cathode, carbon dioxide is reduced to generate ethylene by obtaining electrons on the cathode. The above generated gas is introduced into the absorption module, and the absorbent used is 1 mol / L sodium hydroxide solution. The outlet of the absorption module is connected with a ripening box, and five fruits of the same kind are placed in each box. The ripening fruits used include unripe bananas, mangoes, kiwifruits, papayas and lemons. The power is turned on, and the corresponding preset ripening program is selected for each of the five different fruits. The ripening program for each type of fruit has three levels, and the higher the level, the shorter the ripening time. In addition, the soluble solids and shelf life of kiwifruit change after different ripening levels.

[0086] Table 22 is the ripening time of different fruits in different ripening levels in Example 9.

[0087] Ripening setting Banana Mango Papaya Lemon Ripening setting 1 2.0 days 2.5 days 2.2 days 2.7 days Ripening setting 2 1.2 days 1.1 days 1.0 days 1.4 days Ripening setting 3 0.2 days 0.2 days 0.3 days 0.4 days

[0088] Table 23 is the physicochemical properties of inner kiwifruit in different ripening levels in Example 9

[0089]

[0090] Example 10:

[0091] The power supply system adopts direct current power supply, the electrolysis module in the gas generation chamber has two electrolytic cells, the carbon dioxide cylinder is connected to the cathode gas inlet of the first electrolytic cell, the bipolar plate with a serpentine flow channel is used as the flow channel plate and current collector, nickel oxide is used as the anode and cathode catalyst, the cation conductor is used as the electrolyte, and the reaction temperature is 500 DEG C. The second electrolytic cell uses a bipolar plate with a serpentine flow channel as a flow channel plate and a current collector, and an anion exchange membrane is used to separate the cathode part and the anode part, the cathode gas outlet of the first electrolytic cell is connected to the gas inlet of the second liquid storage tank, the first liquid storage tank is 1 mol / L sodium hydroxide solution, and the second liquid storage tank is pure water. The nanometer copper powder catalyst on the carbon paper is used as the cathode, and the nickel foam is used as the anode, wherein the size of the carbon paper and the nickel foam is 2 cm x 2 cm. The liquid in the first liquid storage tank flows into the anode chamber through the circulating pump, and the flow rate of the first liquid storage tank is controlled to be 50 mL / min. Connect the direct current power supply, control the current density of the constant current electrolysis to be 30 mA / cm 2 , 50 mA / cm 2 , 70 mA / cm 2 , 100 mA / cm 2 , and the electrolysis time under each current density is 30 minutes. The gas generated above is introduced into the separation module. In this embodiment, the separation module uses a hydrogen separation membrane to separate ethylene and hydrogen. The ethylene and hydrogen outlets of the gas separation module are respectively connected to the ripening box and the preservation box, and five fruits of the same kind are placed in each box. The ripening fruits used include unripe bananas, mangoes, kiwis, papayas and lemons, and the preservation fruits used include strawberries, lychees, ripe kiwis, grapes and cherries.

[0092] Table 24 is the selectivity and gas concentration of ethylene and hydrogen generated by electrochemical reduction of CO2 in the gas generation chamber under different current densities in Example 10.

[0093] Example 10 Current density Ethylene selectivity Ethylene concentration Hydrogen selectivity Hydrogen concentration 50 mA / cm 2 ]]> 26.1% 913 ppm 45.9% 3213 ppm 100 mA / cm 2 ]]> 32.4% 2268 ppm 31.4% 4396 ppm 150 mA / cm 2 ]]> 45.1% 4735 ppm 23.7% 4977 ppm 200 mA / cm 2 ]]> 55.9% 7826 ppm 15.1% 4228 ppm

[0094] Table 25 is the ripening time of different fruits in the ripening box under different current densities in Example 10

[0095] Example 10 Current density Banana Mango Kiwi Papaya Lemon 50 mA / cm 2 ]] 2.3 days 1.8 days 3.2 days 2.3 days 3.2 days 100 mA / cm 2 ]] 1.2 days 1.1 days 1.9 days 1.0 days 2.4 days 150 mA / cm 2 ]] 0.5 days 0.5 days 1.1 days 0.8 days 0.7 days 200 mA / cm 2 ]] 0.2 days 0.2 days 0.4 days 0.3 days 0.4 days

[0096] Table 26 is the ripening time of different fruits in the preservation box under different current densities in Example 10

[0097] Example 10 Current density Strawberry Litchi Ripening kiwi Grape Cherry 50 mA / cm 2 ]] 1.7 days 1.8 days 2.9 days 2.5 days 2.4 days 100 mA / cm 2 ]] 2.1 days 2.0 days 4.1 days 3.7 days 2.8 days 150 mA / cm 2 ]] 2.3 days 2.3 days 4.5 days 4.0 days 3.1 days 200 mA / cm 2 ]]> 2.0 days 2.0 days 4.0 days 3.6 days 2.7 days

Claims

1. A fruit and vegetable ripening system characterized by: The system comprises: a power supply system for providing direct current; a gas generation chamber for providing ethylene ripening gas, comprising: an electrolysis module; a liquid storage module; a gas absorption module; a gas separation module for separating ethylene and hydrogen generated by the gas generation chamber and delivering the separated gas to the fruit and vegetable storage chamber or a gas storage tank; a fruit and vegetable storage chamber for storing fruit and vegetables and completing the ripening process; and / or an automatic control subsystem; The electrolysis module in the gas generation chamber comprises an anode, an anode chamber, a cathode, a cathode chamber, a separator, a current collector or a flow channel plate, wherein the anode part and the cathode part are separated by the separator, which includes but is not limited to a cation exchange membrane, an anion exchange membrane, a bipolar membrane, a salt bridge, and an asbestos net; Carbon dioxide is reduced to ethylene under the drive of electricity; The gas absorption module mainly consists of an absorbent and a storage tank, and is connected with the gas generation chamber and the fruit and vegetable storage chamber or the gas separation module; The absorbent receives unreacted carbon dioxide in the gas product generated by the gas generation chamber and carbon dioxide released during the ripening process of fruit and vegetables; The gas absorption module mainly consists of an absorbent and a storage tank, and is connected with the gas generation chamber and the fruit and vegetable storage chamber or the gas separation module; wherein the absorbent is a chemical that absorbs and enriches carbon dioxide, including a mixture of one or more of sodium hydroxide, potassium hydroxide, cesium hydroxide, and porous materials, and is designed to receive unreacted carbon dioxide in the gas product of the cathode chamber in the electrolysis block and carbon dioxide released during the ripening process of fruit and vegetables; the absorbent can be used as raw material in the electrolysis module after being used for a period of time, and the system prompts to replace the absorbent after electrolysis for a certain time at a certain current density; the saturated absorbent is used as electrolyte in the electrolysis module.

2. The ripening system of claim 1, wherein The power supply system includes thermal power generation, photovoltaic power generation, and hydroelectric power generation.

3. The ripening system of claim 1, wherein The raw materials used in the gas generation chamber include carbon dioxide or chemicals that can release carbon dioxide, including but not limited to one or more of bicarbonate, carbonate, and citric acid.

4. The ripening system of claim 1, wherein The electrolysis module includes an electrolytic cell for converting carbon dioxide into carbon monoxide.

5. The ripening system of claim 1, wherein The liquid storage module in the gas generation chamber includes a first liquid storage tank for supplying anode electrolyte and a second liquid storage tank for supplying cathode electrolyte; the system can prompt to replace the electrolyte after working for a certain period of time, and the replaced electrolyte is used as the absorbent of the absorption module.

6. The ripening system of claim 1, wherein The system has a gas separation module for separating hydrogen in the gas generation chamber; the separation method includes a combination of one or more of cold box, separation membrane, and hydrogen adsorbing material.

7. The ripening system of claim 1, wherein The fruit and vegetable storage chamber includes but is not limited to a goods warehouse, a fruit and vegetable storage cabinet, a refrigerator, a ripening vehicle, and a ripening box.

8. The ripening system of claim 1, wherein, The fruit and vegetable storage chamber includes a detection device; the detection device is placed inside the storage chamber to detect the carbon dioxide, ethylene, water vapor, hydrogen content parameters and / or temperature parameters in the storage chamber.

9. The ripening system of claim 1, wherein, The system is provided with an automatic control subsystem, which can adjust the release of ripening gas in the gas generating chamber according to the concentration of gas in the fruit and vegetable storage chamber; when the ethylene concentration in the fruit and vegetable storage chamber is high to the alarm value, the gas generating chamber will automatically reduce the current to reduce or stop the production of ethylene; when the ethylene concentration in the fruit and vegetable storage chamber is lower than the set value, the gas generating chamber increases the generated current to increase the ethylene production rate.

10. The ripening system of claim 1, wherein, When ripening and preservation processes are carried out at the same time, the system adjusts the ratio of ethylene and hydrogen release by changing the tank pressure according to actual needs.

Images