Culture medium, reactor and method based on biomass solid waste and activated carbon

Abstract

The invention discloses a culture medium based on biomass solid waste and activated carbon, a reactor and a method. The gas inlet is formed in the lower end of the reactor tank body; the leachate collecting opening is formed in the lower end of the reactor tank body; the exhaust port is formed in the upper end of the reactor tank body; the sampling port is formed in the side wall of the reactor tank body; the temperature sensor is arranged in the reactor tank body; the exhaust purification device is connected with the exhaust port; the gas supply end of the mixed gas supply device is connected with the gas inlet, and the gas inlet end of the mixed gas supply device is connected with a nitrogen source; and the data recording and control unit is respectively connected with the temperature sensor, the exhaust purification device and the mixed gas supply device. The method can be applied to biomass solid waste resourceful treatment and utilization in an extraterrestrial space controlled ecological life support system and in-situ production of food, and the material closure degree of the system is improved; in addition, the method also has a guiding effect on resourceful treatment, utilization and the like of crop straws in modern agriculture.

Description

Technical Field

[0001] The invention belongs to the field of biomass solid waste resource utilization and plant cultivation, and specifically relates to a cultivation matrix, a reactor and a method based on biomass solid waste and activated carbon. Background Art

[0002] The fundamental way to solve the life support of astronauts in future long-term manned space exploration missions is to establish a controlled ecological life support system (CELSS) with plants as the core. In CELSS, plants can provide oxygen for humans, absorb carbon dioxide, realize water recycling and provide food through photosynthesis. While providing food for astronauts, plants also produce inedible parts such as roots, stems and leaves. This type of biomass solid waste not only contains a large amount of carbon and oxygen elements, but also contains mineral elements required for plant growth. In addition, these plant solid wastes contain organic matter, which will rot and deteriorate if not treated, causing diseases, and have a very adverse effect on the closed environment. Therefore, it is the key to the high material closure and stable operation of the controlled ecological life support system of the extraterrestrial base to treat these biomass solid wastes in a safe, stable and resource-based manner, and reuse the treated products to achieve the utilization of in-situ resources.

[0003] In the field of modern agriculture, the most studied method for treating biomass solid wastes such as plant roots, stems and leaves is to transform these biomass solid wastes into organic fertilizers through microbial aerobic composting and fermentation, thereby achieving the stabilization and resource treatment of such solid wastes, and then applying these organic fertilizers to farmland to achieve material recycling. In long-term manned space exploration missions, this principle can also be used to treat biomass solid wastes such as plant roots, stems and leaves and crew solid excrement in controlled ecological life support systems, and then use the treated products for plant cultivation, thereby achieving the safety, stabilization and resource treatment of biomass solid wastes in controlled ecological life support systems of extraterrestrial bases, and ultimately achieving on-site transformation and recycling of biomass solid wastes in the system.

[0004] However, the existing technology lacks solutions for aerobic composting of solid waste in a controlled ecological biosafety system, quality evaluation of compost products, and reuse of compost products. Summary of the invention

[0005] The purpose of the present invention is to solve the problem that the prior art lacks solutions for aerobic composting of solid waste in a controlled ecological life protection system, quality evaluation of compost products, and reuse of compost products.

[0006] The purpose of the present invention is to adopt the following technical solutions to achieve:

[0007] A closed bioreactor, comprising:

[0008] Reactor tank;

[0009] An air inlet is arranged at the lower end of the reactor tank;

[0010] A leachate collection port is provided at the lower end of the reactor tank;

[0011] An exhaust port is arranged at the upper end of the reactor tank;

[0012] A sampling port is arranged on the side wall of the reactor tank;

[0013] A temperature sensor is arranged inside the reactor tank;

[0014] An exhaust purification device connected to the exhaust port;

[0015] A mixed gas supply device, whose gas supply end is connected to the gas inlet, and whose gas inlet end is connected to a nitrogen source;

[0016] The data recording and control unit is connected to the temperature sensor, the exhaust purification device, and the mixed air supply device respectively.

[0017] Preferably, the reactor further comprises an automatic control system connected to the data recording and control unit and the mixing gas supply device respectively.

[0018] Preferably, the exhaust purification device includes a condensing device connected to the exhaust port, an ammonia absorption device connected to the condensing device, and an exhaust gas analyzer connected to the ammonia absorption device; the exhaust gas analyzer is connected to the data recording and control unit.

[0019] Preferably, the mixed air supply device includes an intake gas analyzer connected to the air inlet, a flow meter connected to the intake gas analyzer, a mixing chamber connected to the flow meter, an air flow meter and an air solenoid valve connected sequentially to the mixing chamber, and a nitrogen flow meter and a nitrogen solenoid valve connected sequentially to the mixing chamber; the air solenoid valve is connected to an air source; the nitrogen solenoid valve is connected to a nitrogen source; the intake gas analyzer, the air solenoid valve, and the nitrogen solenoid valve are electrically connected to the data recording and control unit, respectively.

[0020] Preferably, an aeration plate connected to the mixing and air supply device is provided at the inner bottom of the reactor tank.

[0021] Based on the same inventive concept, the present invention also provides that the cultivation matrix includes a compost product and activated carbon produced by a closed bioreactor as described above; in terms of mass ratio, compost product / activated carbon (mass ratio) = (20-60) / (80-40).

[0022] Preferably, the compost product has a carbon-nitrogen ratio of 20 to 30:1, a pH of 6.5 to 7.5, and an electrical conductivity EC of 2.0 to 8.0 ms / cm.

[0023] Preferably, the activated carbon comes from discarded activated carbon in a controlled ecological life support system.

[0024] Preferably, when planting leafy vegetables such as lettuce, the compost product / activated carbon (mass ratio) = 1 / (4-5).

[0025] Preferably, when growing food crops such as wheat, the compost product / activated carbon (mass ratio) = 1 / (2-5).

[0026] Based on the same inventive concept, the present invention also provides a method for preparing a cultivation substrate based on biomass solid waste and activated carbon, the method comprising the following steps: mixing the compost product produced by a closed bioreactor as described above with the activated carbon.

[0027] Based on the same inventive concept, the present invention also provides an application method of a cultivation substrate based on biomass solid waste and activated carbon, the method comprising the following steps: mixing a cultivation substrate based on biomass solid waste and activated carbon as described in claim 6 with slow-release fertilizer particles; the ratio is 2 to 3 grams of slow-release fertilizer particles per 1 to 3 liters of the cultivation substrate.

[0028] Preferably, the contents of the slow-release fertilizer include ammonium polyphosphate, potassium polyphosphate, phosphate urea, ammonium nitrate phosphorus, potassium nitrate, ammonium molybdate, chelated calcium, chelated magnesium, chelated iron, chelated manganese, chelated copper, and chelated zinc, and the total nutrient content (mass fraction) of the contents is not less than 40%.

[0029] Compared with the prior art, the present invention has the following beneficial effects:

[0030] (1) Targetedness: In response to the demand for recycling of biomass solid waste in the special environment of the controlled ecological life support system, different types of solid waste are made into plant cultivation matrices, and the solid waste in the system is recycled through plant cultivation. The resource treatment and recycling of waste in extraterrestrial space missions is a major problem. The present invention can achieve long-term recycling of biomass solid waste and waste activated carbon in the system, which can not only achieve the resource treatment of solid waste in the system, but also effectively reduce the demand for material supply by making it into plant cultivation matrices for recycling, which is of great significance for the establishment of long-term manned planetary bases on the moon or Mars in the future.

[0031] (2) Simplicity: Through aerobic biological fermentation, the biomass solid waste such as the inedible parts of plants in the controlled ecological life support system is downgraded and mixed with waste activated carbon and other materials in proportion to make a plant cultivation matrix. Then, plant cultivation is carried out to achieve in-situ production of vegetables and other foods in the system. It also achieves the recycling of solid waste and ensures the stability and balance of the material flow in the closed system.

[0032] (3) Practicality: The experimental results, such as the mixing ratio of waste activated carbon and compost products, and the plant growth status, can be applied not only to the recycling of waste and food production in future lunar bases, but also to the resource processing and utilization of crop straw in modern urban agriculture. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 The structure of a closed bioreactor of the present invention is schematically shown;

[0034] Figure 2 The figure is a schematic diagram of the process of preparing and utilizing plant cultivation substrates using biomass solid waste according to the present invention;

[0035] Wherein: 1. Reactor tank; 2. Air inlet; 3. Leachate collection port; 4. Exhaust port; 5. Sampling port; 6. Temperature sensor; 7. Exhaust purification device; 8. Mixing air supply device; 9. Data recording and control unit; 10. Automatic control system; 100. Aeration plate; 200. Insulation cotton; 71. Condensation device; 72. Ammonia absorption device; 73. Exhaust gas analyzer; 81. Intake gas analyzer; 82. Flow meter; 83. Mixing chamber; 84. Nitrogen flow meter; 85. Air flow meter. DETAILED DESCRIPTION

[0036] The technical solution is further described below in conjunction with the accompanying drawings and specific embodiments to help understand the content of the present invention.

[0037] Example 1

[0038] like Figure 1 As shown, a closed bioreactor, the reactor comprising:

[0039] Reactor tank 1;

[0040] An air inlet 2 is arranged at the lower end of the reactor tank 1;

[0041] A leachate collection port 3 is provided at the lower end of the reactor tank 1;

[0042] An exhaust port 4 is provided at the upper end of the reactor tank 1;

[0043] A sampling port 5 is arranged on the side wall of the reactor tank 1;

[0044] A temperature sensor 6 is arranged inside the reactor tank 1;

[0045] An exhaust purification device 7, connected to the exhaust port;

[0046] A mixed gas supply device 8, whose gas supply end is connected to the gas inlet 2, and whose gas inlet end is connected to a nitrogen source;

[0047] The data recording and control unit 9 is connected to the temperature sensor 6 , the exhaust purification device 7 , and the mixed air supply device 8 respectively.

[0048] The reactor further comprises an automatic control system 10 connected to the data recording and control unit 7 and the mixing gas supply device 8 respectively.

[0049] The exhaust gas purification device 7 includes a condensing device 71 connected to the exhaust port, an ammonia absorption device 72 connected to the condensing device 71, and an exhaust gas analyzer 73 connected to the ammonia absorption device 72; the exhaust gas analyzer 73 is connected to the data recording and control unit 9. The main function of the exhaust gas purification device 7 is to purify the gas discharged from the reactor to ensure that the discharged gas components meet the safety requirements. The ammonia absorption device 72 includes an alkali washing tank, an acid washing tank, and an activated carbon adsorption tank. The alkali washing tank is filled with sodium hydroxide or lithium hydroxide, etc., which is used to absorb acidic gases in the exhaust gas, such as hydrogen sulfide, nitrogen oxides, sulfur dioxide, etc.; the acid washing tank is filled with sulfuric acid or nitric acid, etc., which is used to absorb alkaline gases in the exhaust gas, such as ammonia, etc.; the activated carbon adsorption tank is filled with activated carbon, which is used to absorb volatile organic gases in the exhaust gas, such as TVOCs, etc.

[0050] The exhaust gas analyzer 73 is a parameter measurement module, which is mainly used to measure the gas characteristics at different positions of the gas path and the material characteristics in the reactor body, such as the oxygen, carbon dioxide concentration and temperature in the gas at the outlet of the gas supply module, and the oxygen, carbon dioxide, temperature, humidity, ammonia, hydrogen sulfide, methane, nitrogen oxides, TVOCs, etc. in the gas at the outlet of the reactor body and the outlet of the exhaust gas purification treatment module.

[0051] The mixed gas supply device 8 includes an intake gas analyzer 81 connected to the air inlet, a flow meter 82 connected to the intake gas analyzer 81, a mixing chamber 83 connected to the flow meter 82, an air flow meter 85 and an air solenoid valve (integrated in the air flow meter or separately arranged) connected to the mixing chamber 83 in sequence, and a nitrogen flow meter 84 and a nitrogen solenoid valve (integrated in the nitrogen flow meter or separately arranged) connected to the mixing chamber 83 in sequence; the air solenoid valve is connected to an air source; the nitrogen solenoid valve is connected to a nitrogen source; the intake gas analyzer 81, the air solenoid valve, and the nitrogen solenoid valve are electrically connected to the data recording and control unit 9, respectively. The main function of the mixed gas supply device 8 is to provide a suitable gas source for the biomass fermentation process in the reactor tank 1.

[0052] An aeration plate 100 connected to the mixing gas supply device 8 is provided at the inner bottom of the reactor tank body 1, and is mainly used to evenly disperse the gas supplied by the gas supply module to ensure that the gas is evenly distributed in the fermentation material in the reactor body.

[0053] The outer side of the reactor tank 1 is covered with insulation cotton 200. The main function of the reactor tank 1 is to provide a place for biomass solid waste fermentation and has good insulation function. The closed bioreactor is an aerobic composting fermentation device, which is used to carry out aerobic biodegradation of materials and maintain temperature conditions during the fermentation process.

[0054] The exhaust gas purification device 7 realizes exhaust gas monitoring and purification.

[0055] The data recording and control unit 9 includes data display and recording instruments and an automatic control system.

[0056] The system automatically controls and adjusts the ratio of air and nitrogen, configures gases with different oxygen concentrations, and allows them to enter the solid waste reactor body and be used by microorganisms in the reactor. After the tail gas is dried by the condensation device, the water in the solid waste biodegradation process is recovered. The gas then enters the ammonia absorption device for ammonia measurement, and finally enters the exhaust gas analyzer for monitoring other gas components. The stack temperature, intake parameters and exhaust parameters are automatically displayed and recorded in the program, and the test parameters can be set by themselves, and the settings are automatically completed through the automatic control system.

[0057] The purpose of the present invention is to establish a method for resource treatment and recycling of biomass solid waste in the controlled ecological life support system of an extraterrestrial base. First, these wastes are treated with aerobic biological fermentation in a closed bioreactor, and then the characteristics of the obtained treatment products are evaluated for biosafety; on this basis, activated carbon materials used for gas purification in the system are added to make plant cultivation matrix, and then the matrix is ​​used for plant cultivation. Ultimately, the safe and resource treatment and recycling of plant roots, stems and leaves, solid excrement of crew members and waste in the controlled ecological life support system of an extraterrestrial base are realized.

[0058] The key technical problems to be solved by the present invention include:

[0059] (1) Establish the operating conditions of a closed bioreactor to complete the aerobic composting treatment of biomass solid waste in a controlled ecological bioreactor system;

[0060] (2) Establishing evaluation indicators to evaluate the biosafety of the resulting composting products;

[0061] (3) establishing a mixing ratio of compost product and activated carbon to obtain a method for preparing a plant cultivation substrate;

[0062] (4) The cultivation medium obtained after mixing can meet the growth needs of the plants, and the plants can grow normally;

[0063] (5) The plant cultivation matrix can provide certain mineral nutrients to meet the growth of plants.

[0064] The implementation process of the technical solution of the present invention is as follows:

[0065] (1) The collected biomass solid wastes such as plant roots, stems and leaves are placed in a special closed bioreactor for aerobic biocomposting and fermentation treatment.

[0066] The reactor body has a diameter and height ratio of 0.618:1, an effective volume of 20 to 50 liters, and thermal insulation performance that, in the absence of a heat source, the ambient temperature is 25°C, the material temperature is 60°C, and the temperature drop does not exceed 5 to 8°C within 24 hours.

[0067] When the material is fermented, the gas supply flow range of the gas supply module is 0.1-1.0 L / min, the initial moisture content of the material is 60-70%, and the carbon-nitrogen ratio is 20-30:1.

[0068] Material fermentation time: 15 to 30 days.

[0069] (2) The products obtained after aerobic composting and fermentation of biomass solid waste such as plant roots, stems and leaves are first evaluated for biosafety. The main test indicators are germination index GI, conductivity EC, pH, etc. Among them, the germination index GI is required to be greater than 80%, and other test results such as conductivity and pH are used as reference indicators. The compost product with a germination index GI greater than 80% can be used as a material for plant cultivation substrates to carry out the next step of plant cultivation experiments.

[0070] (3) Establishing the mixing ratio of compost products and activated carbon to obtain a method for preparing a plant cultivation matrix: Since compost products contain a lot of organic matter, there are some problems with direct plant cultivation, such as poor aeration and poor water and fertilizer retention. Before these compost products are used, they are generally mixed with other materials before being used for plant cultivation. In agricultural production practice, they can be directly applied to the soil and mixed with the soil, and the amount of application must take into account the properties of the compost products, otherwise it is easy to cause seedling burn. In the controlled ecological life protection system, how to reuse the compost products of the inedible parts of these plants is an issue that must be considered. The gas purification subsystem is a key component of the controlled ecological life protection system. This subsystem uses activated carbon adsorption, catalytic oxidation and other methods to purify the gas. Activated carbon is a consumable required during the operation of the system. After a period of time, the adsorption capacity of activated carbon weakens, and it can generally be reactivated by heating and other methods. However, its adsorption performance gradually weakens with the increase in the number of reactivations. In this way, the deactivated activated carbon becomes a waste in the system. However, this kind of discarded activated carbon still has characteristics such as a relatively developed pore structure. In addition, the granular structure of these discarded activated carbons is conducive to improving the air permeability of the compost product. If these discarded activated carbons are added to the compost product in a suitable ratio, the characteristics of the compost product can be improved so that it meets the requirements of being a plant cultivation matrix. In this way, not only can the inedible parts of plants and organic wastes such as crew feces in the controlled ecological life support system be safely and resourcefully treated, but also the discarded activated carbon in the system can be reused, thereby realizing the recycling of organic waste in the system, which is of great significance to improving the material closure of the closed system of long-term manned space missions. Therefore, the characteristics of the discarded activated carbon and the compost product obtained from solid waste treatment in the integrated system are mixed in a certain proportion to make a plant cultivation matrix for plant cultivation, thereby realizing the resource treatment and recycling of waste in the controlled ecological life support system, which is of great significance to improving the material closure of the controlled ecological life support system of the future extraterrestrial planetary base. In addition, this technology can also be applied to the recycling of straw in modern agriculture.

[0071] Example 2

[0072] Based on the same inventive concept, the present invention also provides a cultivation matrix based on biomass solid waste and activated carbon, wherein the cultivation matrix includes a compost product and activated carbon produced by a closed bioreactor as described in Example 1; in terms of mass ratio, compost product / activated carbon (mass ratio) = (20-60) / (80-40).

[0073] Preferably, the compost product has a carbon-nitrogen ratio of 20 to 30:1, a pH of 6.5 to 7.5, and an electrical conductivity EC of 2.0 to 8.0 ms / cm.

[0074] Preferably, the activated carbon comes from the discarded activated carbon in the controlled ecological life support system, and has a particle size of 1 to 3 mm, of which 1 to 2 mm accounts for 85 to 90%, and 2 to 3 mm accounts for 5 to 10%.

[0075] The compost product is derived from biomass solid waste such as inedible parts of plants and feces fermented in a closed bioreactor as described in Example 1 for 20 to 30 days. The initial moisture content of the compost product is 60 to 70%, the carbon-nitrogen ratio is 20 to 30:1, and the physical and chemical properties of the compost product are bulk density of 0.05 to 0.10 g / cm 3 , germination index GI is not less than 75%, pH value is 6.5-7.5, and electrical conductivity EC is 2.0-8.0ms / cm.

[0076] The cultivation matrix is ​​derived from the above-mentioned mixture consisting of compost product and activated carbon, and the ratio of the two is determined based on the plant species to be planted, wherein: ① when planting leafy vegetables such as lettuce, the compost product: compost product / activated carbon (mass ratio) = 1 / (4-5); ② when planting grain crops such as wheat, the compost product / activated carbon (mass ratio) = 1 / (2-5).

[0077] The cultivation substrate preparation process is to uniformly mix the collected compost product and activated carbon according to the aforementioned set ratio, and then put them into the plant cultivation pot.

[0078] The plant culture pot is generally a small round or square plastic pot with a volume of 1 to 3 liters.

[0079] After the cultivation substrate is loaded into a plant cultivation pot, 2 to 3 grams of slow-release fertilizer particles are added to each plant cultivation pot, and then 5 to 10 plant seeds to be cultivated are sown into the cultivation substrate.

[0080] The slow-release fertilizer particles contain all 16 essential nutrient elements required for plant growth, and the content of each element is basically consistent with the quantity and proportion required for plant growth.

[0081] The slow-release fertilizer granules are made of raw materials including ammonium polyphosphate, potassium polyphosphate, phosphate urea, ammonium nitrate phosphorus, potassium nitrate, ammonium molybdate, chelated calcium, chelated magnesium, chelated iron, chelated manganese, chelated copper and chelated zinc. The total nutrient content (mass fraction) is not less than 40%.

[0082] The plant seeds need to be soaked in tap water or purified water for 12 to 24 hours before sowing.

[0083] After sowing, the plant culture pots containing the cultivation substrate are placed in the plant light cultivation device. The environmental conditions of the plant light cultivation device are set as follows: ① Germination period, temperature 18-22°C, no light; ② Germination 1-10 days, temperature 18-22°C, light 50-100 μmol·m -2 ·s -1 PPFD; ③ After seedling selection: On the 10th day after germination, the seedlings are selected. The number of seedlings is determined according to the plant species. Generally, 1 to 3 seedlings are selected per pot. At this time, the temperature is 20 to 25°C and the light intensity is 100 μmol·m -2 ·s -1 PPFD gradually increased to 200-450 μmol·m -2 ·s -1 PPFD, the maximum light intensity value is determined by the plant species. Generally, the maximum light intensity of vegetable crops is 200-300 μmol·m -2 ·s -1 PPFD, the maximum light intensity for food crops is 300-450 μmol·m -2 ·s -1 PPFD. The atmospheric carbon dioxide concentration for plant cultivation is set at 500-2000ppm.

[0084] During the plant cultivation process, the water content of the substrate is measured in real time by a portable soil moisture parameter tester. When the reading value of the portable soil moisture parameter tester is lower than 30% to 40%, water is added to the substrate until the reading value of the portable soil moisture parameter tester reaches 45% to 50%.

[0085] During the plant cultivation process, the growth status of the plants needs to be observed daily, and water needs to be added in time according to the water content of the cultivation substrate. When the plants grow and mature, they can be harvested.

[0086] The present invention utilizes biomass solid waste to prepare and utilize the plant cultivation matrix. Figure 2 As shown, the specific implementation process is as follows:

[0087] 1. Resource treatment process of biomass solid waste such as inedible parts of plants

[0088] 1. Test materials

[0089] The main aerobic composting treatment was conducted on wheat straw and feces. ① The wheat straw came from Lianyungang, Jiangsu; ② The simulated feces components were: wheat bran (37.5% by mass, the same below), yeast powder (37.5%), commercial peanut oil (20%), KCl (4%), and Ca(H2PO4)2 (1%).

[0090] 2. Test methods

[0091] 2.1 The experimental apparatus uses a closed bioreactor as described in Example 1.

[0092] 2.2 Material preparation

[0093] (1) Prepare 226.4 g simulated feces dry basis: take 84.90 g wheat bran powder, 84.90 g yeast powder, 45.28 g peanut oil, 9.06 g KCl and 2.26 g Ca(H2PO4)2 and mix well.

[0094] (2) Take 1523.6g of wheat straw and 226.4g of simulated feces, add 3250g of pure water (first pour part of the pure water into the simulated feces to mix the simulated feces evenly, and then use the remaining pure water to mix the wheat straw and simulated feces evenly), adjust the moisture content of the mixture to about 65%, and then add 25g of QM microbial agent and mix evenly (the amount of microbial added is 0.5% of the wet base mass of the mixture).

[0095] (3) 4.5 kg of mixed materials were added to the reactors respectively, and the volume of the composting device was 20 L.

[0096] 2.3 Fermentation treatment

[0097] Start the device and adjust the oxygen concentration to 15% to 21% through the automatic control system according to 0.050m 3 ·(m 3 ·min) -1 The ventilation rate is 1L·min -1 A mixed gas with an oxygen concentration of 15% to 21% is supplied to the reactor to start the biological aerobic fermentation test.

[0098] During the test, ensure that the ventilation conditions are consistent. Collect samples regularly during the fermentation period, focusing on testing indicators such as the pH value, electrical conductivity (EC), humic acid optical properties (E4 / E6) and seed germination index (GI) of the samples to evaluate the degree of maturity of the product. When the germination index (GI) of the sample is greater than 75%, the test can be stopped. At this time, the fermentation treatment time is generally about 15 to 30 days. The specific time is determined by the germination index of the sample. After stopping the test, the compost sample is removed from the main unit of the reactor and preserved as a material for making plant cultivation substrates.

[0099] 2. Plant cultivation substrate preparation process

[0100] 1. Test materials

[0101] Compost product: The compost product obtained after aerobic composting and fermentation treatment, the physical and chemical properties of the compost product are bulk density 0.05-0.10g / cm 3 , germination index GI is not less than 75%, pH value is 6.5-7.5, and electrical conductivity EC is 2.0-8.0ms / cm.

[0102] Waste activated carbon: waste activated carbon from controlled ecological life support systems, with a particle size of 1 to 3 mm, of which 1 to 2 mm accounts for 85 to 90%, and 2 to 3 mm accounts for 5 to 10%.

[0103] 2. Matrix preparation process

[0104] The aforementioned test materials were mixed according to a mass ratio, and the mixing ratio of the two was set to be compost product: activated carbon (mass ratio) = (20-60): (80-40).

[0105] The mixed material is the prepared plant cultivation medium, which is stored and used as the cultivation medium for plant cultivation in the next step.

[0106] 3. Plant cultivation process

[0107] 1. Test materials

[0108] ① Cultivation substrate: the prepared plant cultivation substrate, wherein the mass ratio of the compost product to the activated carbon is 1:4;

[0109] ②Plant variety: Italian lettuce king, selected from the variety produced by Shandong Shouhe Seed Co., Ltd.

[0110] 2. Cultivation methods and steps

[0111] The aforementioned compost product and waste activated carbon are thoroughly mixed in a mass ratio of 1:4.

[0112] The aforementioned mixed materials are placed in a plant culture pot, which is a small round or square plastic pot with a volume of 2.0 liters.

[0113] After the pots are filled, add 2 to 3 grams of slow-release fertilizer granules to each plant culture pot. The slow-release fertilizer granules contain all 16 essential nutrient elements required for plant growth, and the content of each element is basically consistent with the quantity and proportion required for plant growth. The raw materials used for granulation are ammonium polyphosphate, potassium polyphosphate, phosphate urea, ammonium nitrate phosphorus, potassium nitrate, ammonium molybdate, chelated calcium, chelated magnesium, chelated iron, chelated manganese, chelated copper, and chelated zinc. The total nutrient content (mass fraction) is not less than 40%.

[0114] Then, 5 to 10 seeds of the plant to be cultivated are sown into the cultivation medium at a sowing depth of 2 to 3 cm. The plant seeds need to be soaked in tap water or purified water for 12 to 24 hours before sowing.

[0115] 3. Plant culture conditions

[0116] After sowing, the plant culture pots containing the cultivation substrate are placed in the plant light cultivation device. The environmental conditions of the plant light cultivation device are set as follows: ① Germination period, temperature 18-22°C, no light; ② Germination 1-10 days, temperature 18-22°C, light 50-100 μmol·m -2 ·s -1 PPFD; ③ After seedling selection: On the 10th day after germination, the seedlings are selected. The number of seedlings is determined according to the plant species. Generally, 1 to 3 seedlings are selected per pot. At this time, the temperature is 20 to 25°C and the light intensity is 100 μmol·m -2 ·s -1 PPFD gradually increased to 200-300 μmol·m -2 ·s -1 PPFD. The atmospheric carbon dioxide concentration value for plant cultivation is set to 500±50ppm 20 days before cultivation; and set to 2000±100ppm after 20 days.

[0117] 4. Plant cultivation management and harvesting

[0118] At different growth stages of the plants, the temperature, light, atmospheric carbon dioxide concentration and other conditions are set according to the aforementioned plant culture conditions.

[0119] During the plant cultivation process, the growth status of the plants needs to be observed daily, and water needs to be added in time according to the water content of the cultivation substrate. The water content of the substrate is measured in real time by a portable soil moisture parameter tester. When the reading of the portable soil moisture parameter tester is lower than 30%, water is added to the substrate until the reading of the portable soil moisture parameter tester reaches 45%.

[0120] After 10 days of germination, the seedlings are transplanted, with 2 seedlings per tray.

[0121] During the plant cultivation process, the growth status of the plants needs to be observed daily, and the plant height and leaf area need to be collected and recorded regularly.

[0122] The plants were harvested 30 days after transplanting, and the fresh weight, plant height and other indicators were recorded.

[0123] At harvest, samples of the growing medium were collected;

[0124] When the plants were harvested, they were collected by pots and the above-ground and underground parts of the plants were placed in kraft paper bags respectively. The samples were dried at 85±5℃. After drying to constant weight, the samples were weighed and recorded respectively.

[0125] The present invention aims at the demand for recycling of biomass solid waste in the special environment of the controlled ecological life support system, and makes different types of solid waste into plant cultivation matrix, and realizes the recycling of solid waste in the system through plant cultivation. The resource treatment and recycling of waste in extraterrestrial space missions is a major problem. The present invention can realize the long-term recycling of biomass solid waste and discarded activated carbon in the system, which can not only realize the resource treatment of solid waste in the system, but also effectively reduce the demand for material supply by making it into plant cultivation matrix for recycling, which is of great significance for the establishment of long-term manned planetary bases on the moon or Mars in the future.

[0126] The present invention uses an aerobic biological fermentation method to downgrade biomass solid wastes such as inedible parts of plants in a controlled ecological life support system, and then mixes them with discarded activated carbon and other materials in proportion to conveniently make them into plant cultivation substrates, and then carries out plant cultivation, thereby achieving in-situ production of vegetables and other foods in the system, and realizing the recycling of solid wastes, ensuring the stability and balance of material flow in the closed system.

[0127] The results obtained in the experiment of the present invention, such as the mixing ratio of waste activated carbon and compost products, and the results such as the plant growth status, can be applied not only to the recycling of waste and food production in the future lunar base, but also to the resource processing and utilization of crop straw in modern urban agriculture.

[0128] Example 3

[0129] Based on the same inventive concept, the present invention also provides a method for preparing a cultivation matrix based on biomass solid waste and activated carbon, the method comprising the following steps: mixing the compost product produced by a closed bioreactor as described in Example 1 with activated carbon, the proportion and implementation process are as described in Example 2, and the necessary technical contents not mentioned are all prior art, so they will not be repeated.

[0130] Example 4

[0131] Based on the same inventive concept, the present invention also provides an application method of a cultivation substrate based on biomass solid waste and activated carbon, the method comprising the following steps: mixing a cultivation substrate based on biomass solid waste and activated carbon as described in Example 2 with slow-release fertilizer granules; the ratio is 2 to 3 grams of slow-release fertilizer granules per 1 to 3 liters of the cultivation substrate.

[0132] Preferably, the contents of the slow-release fertilizer include ammonium polyphosphate, potassium polyphosphate, phosphate urea, ammonium nitrate phosphorus, potassium nitrate, ammonium molybdate, chelated calcium, chelated magnesium, chelated iron, chelated manganese, chelated copper, and chelated zinc, and the total nutrient content (mass fraction) of the contents is not less than 40%.

[0133] The above are merely embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention are included in the scope of the claims of the present invention.

Claims

1. A closed bioreactor, characterized in that: The reactor comprises: Reactor tank; An air inlet is arranged at the lower end of the reactor tank; A leachate collection port is provided at the lower end of the reactor tank; An exhaust port is arranged at the upper end of the reactor tank; A sampling port is arranged on the side wall of the reactor tank; A temperature sensor is arranged inside the reactor tank; An exhaust purification device connected to the exhaust port; A mixed gas supply device, whose gas supply end is connected to the gas inlet, and whose gas inlet end is connected to a nitrogen source; The data recording and control unit is connected to the temperature sensor, the exhaust purification device, and the mixed air supply device respectively.

2. A closed bioreactor according to claim 1, characterized in that: The reactor further comprises an automatic control system connected to the data recording and control unit and the mixing gas supply device respectively.

3. A closed bioreactor according to claim 1, characterized in that: The exhaust gas purification device includes a condensing device connected to the exhaust port, an ammonia absorption device connected to the condensing device, and an exhaust gas analyzer connected to the ammonia absorption device; the exhaust gas analyzer is connected to the data recording and control unit.

4. A closed bioreactor according to claim 2, characterized in that: The mixed air supply device includes an intake gas analyzer connected to the air inlet, a flow meter connected to the intake gas analyzer, a mixing chamber connected to the flow meter, an air flow meter and an air solenoid valve connected sequentially to the mixing chamber, and a nitrogen flow meter and a nitrogen solenoid valve connected sequentially to the mixing chamber; the air solenoid valve is connected to an air source; the nitrogen solenoid valve is connected to a nitrogen source; the intake gas analyzer, the air solenoid valve, and the nitrogen solenoid valve are electrically connected to the data recording and control unit, respectively.

5. A closed bioreactor according to claim 1, characterized in that: An aeration plate connected to the mixing and air supply device is arranged at the inner bottom of the reactor tank.

6. A cultivation substrate based on biomass solid waste and activated carbon, characterized in that: The cultivation matrix comprises a compost product and activated carbon produced by a closed bioreactor as described in any one of claims 1 to 5; in terms of mass ratio, the compost product / activated carbon = (20-60) / (80-40); the activated carbon comes from activated carbon discarded in a controlled ecological life support system.

7. A cultivation substrate based on biomass solid waste and activated carbon as claimed in claim 6, characterized in that: The compost product has a carbon-nitrogen ratio of 20 to 30:1, a pH of 6.5 to 7.5, and an electrical conductivity EC of 2.0 to 8.0 ms / cm.

8. A cultivation substrate based on biomass solid waste and activated carbon as claimed in claim 6, characterized in that: When planting leafy vegetables such as lettuce, the compost product / activated carbon (mass ratio) = 1 / (4~5).

9. A cultivation substrate based on biomass solid waste and activated carbon as claimed in claim 6, characterized in that: When growing food crops such as wheat, the compost product / activated carbon (mass ratio) = 1 / (2~5).

10. A method for preparing a cultivation substrate based on biomass solid waste and activated carbon, characterized in that: The method comprises the following steps: mixing the compost product produced by a closed bioreactor as claimed in any one of claims 1 to 5 with activated carbon.

11. An application method of a cultivation substrate based on biomass solid waste and activated carbon, characterized in that: The method comprises the following steps: mixing a cultivation substrate based on biomass solid waste and activated carbon as claimed in claim 6 with slow-release fertilizer particles; The ratio is 2 to 3 grams of slow-release fertilizer granules per 1 to 3 liters of the cultivation substrate.

12. The method for applying a cultivation substrate based on biomass solid waste and activated carbon according to claim 11, characterized in that: The contents of the slow-release fertilizer include ammonium polyphosphate, potassium polyphosphate, phosphate urea, ammonium nitrate phosphorus, potassium nitrate, ammonium molybdate, chelated calcium, chelated magnesium, chelated iron, chelated manganese, chelated copper, and chelated zinc, and the total nutrient content (mass fraction) of the contents is not less than 40%.

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