A universal film structure bag and a method for manufacturing the same

Abstract

The present application relates to a kind of universal membrane structure bag and its preparation method, including membrane structure bag body, the inside of the membrane structure bag body is longitudinally arranged with nine layers of structure from bottom to top;Nine layers of structure is respectively by the part of soil to be improved / restored and after fixing microorganism, biochar, litter, humic acid ammonia etc..The method includes S1, membrane structure bag body preparation;S2, the preparation of biochar;S3, the preparation of litter;S4, culture microorganism;S5, the preparation of humic acid ammonia;S6, microorganism immobilization.The present application can effectively solve the technical problems such as single repair project, poor repair durability in the process of soil improvement and restoration, while can increase the carbon sequestration capacity of soil, prevent and treat soil hardening, improve soil ecological environment, improve crop yield.

Description

TECHNICAL FIELD

[0001] The present application relates to a universal membrane structure bag and a preparation method thereof. BACKGROUND

[0002] At present, there are various methods and technologies in the soil improvement and remediation industry, mainly including physical, chemical and biological methods, each with advantages and disadvantages. The physical method uses technologies such as heating and electrolysis, which is high in energy consumption and cost, and is generally used for site remediation, which is not conducive to large-scale soil remediation; the chemical method is easy to cause secondary pollution, or the cost of using non-polluting materials is high; the biological method is pollution-free, and is becoming a method that the remediation industry pays more and more attention to, but the conventional biological method is slow in effect and short in duration, and needs to be used multiple times, which increases the cost and increases the difficulty of application, and also interferes with normal agricultural activities. The existing methods have common problems, that is, when improving / remediating a certain soil problem, multiple problems cannot be considered. SUMMARY

[0003] In view of the above problems, the purpose of the present application is to provide a universal membrane structure bag and a preparation method thereof, which can effectively solve the problems of single remediation project, poor remediation durability in the process of soil improvement and remediation, and can increase the soil carbon sequestration capacity, prevent and control soil hardening, improve the soil ecological environment, and improve crop yield.

[0004] The technical scheme adopted by the present application is as follows:

[0005] The universal membrane structure bag provided by the present application comprises a membrane structure bag body; nine layers of structures are vertically arranged in the membrane structure bag body from bottom to top, the bottommost layer of structure is flatly arranged with 5-10mm of soil to be improved / remediated as a first layer of structure; biochar, humic acid ammonia and small particle litter after fixing microorganisms are arranged on the surface of the first layer of structure as a second layer of structure; 5-10mm thick soil to be improved / remediated is arranged on the surface of the second layer of structure as a third layer of structure; biochar, humic acid ammonia and large particle litter after fixing microorganisms are arranged in the middle area of the surface of the third layer of structure, and biochar, humic acid ammonia and small particle litter after fixing microorganisms are arranged in the peripheral area as a fourth layer of structure; 5-10mm thick soil to be improved / remediated is arranged on the surface of the fourth layer of structure as a fifth layer of structure; the sixth to seventh layers of structure repeat the operation of the fourth to fifth layers of structure, and the seventh to eighth layers of structure repeat the operation of the second to third layers of structure; 5-10mm of soil to be improved / remediated is arranged on the surface of the eighth layer of structure as a ninth layer of structure; and holes with different diameters are randomly arranged on the top surface of the membrane structure bag body.

[0006] Further, the membrane structure bag body is a degradable fiber membrane or plastic.

[0007] A preparation method of a universal membrane structure bag, the method comprising the following steps:

[0008] S1, preparing the film structure bag body;

[0009] S2, preparing biochar;

[0010] S3, preparing litter;

[0011] S4, cultivating microorganisms;

[0012] S5, preparing humic acid ammonia;

[0013] S6, immobilizing microorganisms.

[0014] Further, the step S2 comprises:

[0015] S2.1, preparing kitchen waste biochar: mixing vegetables, fruit peels, food residues, crushed bones and eggshells and fruit pits in a ratio of 50:20:20:5:5, crushing and placing in an oven at 55-65°C for drying for 3.5-4.5h to obtain large-particle kitchen waste, then further crushing and passing through a 2mm sieve, then dividing the kitchen waste into two parts, one part being pyrolyzed under anaerobic conditions at 750-850°C for 3.5-4.5h, then being cooled to room temperature after being reduced to 55-65°C, obtaining primary biochar, and grinding the biochar through a 100-mesh sieve; the other part being pyrolyzed under anaerobic conditions at 350-450°C for 3.5-4.5h, then being cooled to room temperature after being reduced to 55-65°C, obtaining primary biochar, and grinding the biochar through a 60-mesh sieve;

[0016] S2.2, preparing ordinary biochar: crushing corn stalks with a crusher, then pyrolyzing under anaerobic conditions at 350-450°C, 550-650°C and 750-850°C for 3.5-4.5h respectively, taking out after the temperature is reduced to room temperature, grinding, and passing through 60-mesh and 100-mesh sieves respectively to obtain straw biochar of different particle sizes and pore sizes; crushing wood chips with a crusher, then carbonizing and heat treating at 550-650°C, 750-850°C, 950-1050°C and 1250-1350°C for 6.5-7.5h respectively, taking out after the temperature is reduced to room temperature, grinding, and passing through 60-mesh and 100-mesh sieves respectively to obtain wood chip biochar of different particle sizes and pore sizes; then mixing corn biochar and wood chip biochar of the same particle size.

[0017] Further, the step S3 comprises: grinding fresh and slightly decomposed litter, passing through 18-mesh and 60-mesh sieves, and obtaining large-particle litter and small-particle litter respectively.

[0018] Further, the step S4 comprises: selecting actinomycetes, arbuscular mycorrhizal fungi and bacillus subtilis as the base microorganisms, and culturing the microorganisms in a liquid medium.

[0019] Further, the step S5 comprises: weighing humic acid, adding deionized water to dilute 1000 times, adding ammonia water with a volume of 20 times of the humic acid, putting into a container and ultrasonic oscillation for 8-12 min, fully reacting under magnetic stirring at 35-45 DEG C for 5.5-6.5 h, then cooling and precipitating at room temperature for 10-14 h, filtering the mixed solution through a cellulose membrane, and filtering impurities for standby; then freeze-drying the mixed solution, and constant temperature drying at 90 DEG C to form a solid.

[0020] Further, the step S6 comprises: mixing the biochar and the bacterial suspension with different particle sizes in a conical flask by using the adsorption fixation method, and the ratio of the bacterial agent to the biochar is 1:3-1:30, and then oscillating and culturing for 23-25 h, then centrifuging at 3500 r / min for 4-6 min to discard the supernatant, washing with sterile water, and then putting into a vacuum freeze-drying box for drying, and obtaining the biochar with fixed microorganisms after drying for 23-25 h.

[0021] Compared with the prior art, the present application has the following beneficial effects:

[0022] 1. Different types of carbide substances can be produced by using different carbon raw materials and different temperature heat treatment methods, which can provide nutrient resources for different types of soil organisms and meet the needs of most organisms. For example, bacteria decompose easily decomposable carbon sources, and fungi decompose difficult decomposable carbon sources.

[0023] 2. Different particle sizes of biochar produce different effects. Large particle size biochar has a long decomposition time, is placed in the center of the membrane structure, and has a slow-release effect, prolonging the action time and achieving the effect of continuous treatment. Small particle size biochar is distributed on the periphery of the membrane structure and can be preferentially decomposed by microorganisms, meeting the timeliness requirements of soil improvement and repair.

[0024] 3. The produced large pore diameter carbon can form channels, which is beneficial to adjusting the structure of soil aggregates, preventing soil hardening, and adsorbing pollutants; the produced small pore diameter carbon has a minimum pore diameter of 0.1 microns or smaller connected micropores. Such ultra-micropores have the ability to break up absorbed water molecules, and these water molecules can return to the soil where plants grow, improving the water holding capacity of the soil.

[0025] 4. The biochar of kitchen waste contains a large amount of organic matter such as sugars, proteins, and lipids. The high nitrogen content of Chinese kitchen waste results in a low carbon / nitrogen ratio (10-20), and the use of biochar with a high carbon / nitrogen ratio can maintain the soil carbon / nitrogen ratio in a suitable environment for microbial growth.

[0026] 5. Ammoniation of humic acid can bring nitrogen elements into the soil and adjust the carbon / nitrogen ratio of the soil to prevent the carbon / nitrogen ratio of the soil from being too high due to the addition of carbon, which is not conducive to the decomposition of nutrients by soil microorganisms.

[0027] 6、Selecting microorganisms Actinomyces, arbuscular mycorrhizal fungi and Bacillus subtilis as basic microorganisms, the mycelium of Actinomyces can penetrate the soil to prevent soil compaction; arbuscular mycorrhizal fungi can provide soil carbon sequestration capacity; Bacillus subtilis is a multi-purpose auxiliary bacteria that has effects on pesticide degradation, heavy metal passivation, and promotion of nutrient cycling.

[0028] 7、The porous membrane can provide channels for different sizes of organisms in the soil, small pore sizes can allow bacteria and fungi to pass through, medium pore sizes can allow bacteria, fungi, protozoa, nematodes, and small soil animals to pass through, and large pore sizes can allow large soil animals to pass through, providing resources for different soil animals. The diffusion of biochar, humic acid, and microorganisms in the membrane is affected by soil animal activity, water flow caused by precipitation, and plant root growth.

[0029] 8、Using a membrane structure bag in the soil surface structure compared with direct scattering of soil conditioner, a) provides a fixed nutrient source for soil microorganisms, attracts surrounding soil microorganisms, and ultimately attracts large soil animals through the flow of soil organisms, loosens the soil, prevents soil compaction, spreads nutrients, promotes plant nutrient uptake, enhances soil organism interactions, and improves soil food web structure; b) the membrane structure is relatively fixed in the soil, which can have a long-lasting effect, and its porous structure can not only ensure the flow and diffusion of soil organisms and nutrients in the membrane, but also prevent the loss of membrane materials due to rainwater erosion, thereby reducing the effect.

[0030] 9、The membrane structure bag itself has multiple functions, including preventing soil compaction, treating pollution, and improving soil carbon sequestration capacity; the membrane structure bag can also be considered as a basic carrier structure, which can provide habitats and resources for various bacteria, and based on the existing three types of microorganisms, different strains can be added according to different requirements to adjust the ratio of bacteria to carbon and achieve different effects; other carbon sources such as kelp residue can also be added to acidify the soil to increase the soil pH and achieve multiple soil improvement / remediation effects, allowing for application in multiple scenarios and conditions. BRIEF DESCRIPTION OF DRAWINGS

[0031] Figure 1 is a cross-sectional structure schematic diagram of a universal membrane structure bag according to the present application;

[0032] Figure 2 is a schematic diagram of the growth of petunias after adding a cadmium solution for 20 days in the experimental example;

[0033] Figure 3 is a schematic diagram of the growth of petunias after adding a cadmium solution for 40 days;

[0034] Figure 4 is a schematic diagram of the growth of petunias after adding ethylamides for 40 days.

[0035] Wherein, the reference numerals: 1-biochar after immobilization of large particles of microorganisms; 2-biochar after immobilization of small particles of microorganisms; 3-litter of large particles; 4-litter of small particles; 5-humic acid ammonia; 6-membrane hole; 7-surface; 8-membrane structure bag body. DETAILED DESCRIPTION

[0036] In order to more clearly illustrate the technical solutions of the embodiments of the present application or the prior art, the drawings needed to be used in the embodiments or the prior art description will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present application, and other drawings can also be obtained by those skilled in the art without creative labor on the basis of these drawings.

[0037] It should be noted that in the description of the present application, the terms "upper", "lower", "top", "bottom", "middle", "one side", "the other side", "left", "right" and the like indicate the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not mean that the device or element must have a particular orientation, be constructed and operated in a particular orientation.

[0038] Referring to the accompanying drawings Figure 1 , a specific structure of an embodiment of a universal membrane structure bag proposed by the present application is given. The membrane structure bag comprises a membrane structure bag body 8; the inside of the membrane structure bag body is longitudinally provided with nine layers of structures from bottom to top, the bottommost layer of structure is laid with 5-10mm of soil to be improved / repaired as a first layer of structure; the surface of the first layer of structure is sown with biochar 2 after immobilization of small particles of microorganisms, humic acid ammonia 5 and small particles of litter 4 as a second layer of structure; the surface of the second layer of structure is covered with 5-10mm thick soil to be improved / repaired as a third layer of structure; the middle area of the surface of the third layer of structure is sown with biochar 1 after immobilization of large particles of microorganisms, humic acid ammonia 5 and large particles of litter 3, and the peripheral area is sown with biochar 2 after immobilization of small particles of microorganisms, humic acid ammonia 5 and small particles of litter 4, which together serve as a fourth layer of structure; the surface of the fourth layer of structure is covered with 5-10mm thick soil to be improved / repaired as a fifth layer of structure; the sixth to seventh layers of structure repeat the operation of the fourth to fifth layers of structure, and the seventh to eighth layers of structure repeat the operation of the second to third layers of structure; the surface of the eighth layer of structure is laid with 5-10mm of soil to be improved / repaired as a ninth layer of structure; the top surface of the membrane structure bag body 8 is randomly provided with holes of different diameters. Appropriate water can be added to the inside of the membrane structure bag to adjust the moisture content to 8-12%, and press to keep the structure inside the membrane structure bag from being loose.

[0039] A preparation method of a universal membrane structure bag, the method comprising the following steps:

[0040] S1. Preparation of the membrane structure bag body;

[0041] The membrane structure bag body is made of biodegradable fiber membrane or plastic; the mold is selected according to the size of the membrane structure bag to be used, and a rectangular shell made of plastic or metal can be used, with the top being detachable;

[0042] Lay the bottom of the membrane structure flat to the bottom of the cuboid mold, ensuring that the membrane around the membrane structure is higher than the mold, and leave enough membrane length on one side for folding and sealing.

[0043] S2, Preparation of biochar;

[0044] S2.1 Preparation of biochar from kitchen waste: Vegetables, fruit peels, food scraps, bone fragments, and eggshells and fruit pits are mixed evenly in a ratio of 50:20:20:5:5, crushed, and dried in an oven at 55-65℃ for 3.5-4.5 hours to obtain large particles of kitchen waste. These particles are then further crushed and passed through a 2mm sieve. The kitchen waste is then divided into two portions. One portion is subjected to anaerobic pyrolysis at 750-850℃ for 3.5-4.5 hours, then cooled to 55-65℃ and then to room temperature to obtain primary biochar. This primary biochar is then ground through a 100-mesh sieve. The other portion is subjected to anaerobic pyrolysis at 350-450℃ for 3.5-4.5 hours, then cooled to 55-65℃ and then to room temperature to obtain primary biochar. This primary biochar is then ground through a 60-mesh sieve.

[0045] S2.2 Preparation of ordinary biochar: Corn stalks were crushed using a pulverizer and then subjected to anaerobic pyrolysis at 350-450℃, 550-650℃, and 750-850℃ for 3.5-4.5 hours, respectively. After the temperature was lowered to room temperature, the stalks were removed, ground, and passed through 60-mesh and 100-mesh sieves to obtain straw biochar with different particle sizes and pore sizes. Wood chips were crushed using a pulverizer and then carbonized. They were heat-treated at 550-650℃, 750-850℃, 950-1050℃, and 1250-1350℃ for 6.5-7.5 hours, respectively. After the temperature was lowered to room temperature, the wood chips were removed, ground, and passed through 60-mesh and 100-mesh sieves to obtain wood chip biochar with different particle sizes and pore sizes. Then, corn biochar and wood chip biochar of the same particle size were mixed separately.

[0046] S3. Preparation of litter;

[0047] Fresh and slightly decomposed litter was ground and passed through 18-mesh and 60-mesh sieves to obtain large-particle litter and small-particle litter, respectively, and placed in the corresponding layer structure inside the membrane structure bag body 8.

[0048] S4. Cultivate microorganisms;

[0049] The basic microorganisms selected were actinomycetes, fascicular mycorrhizal fungi, and Bacillus subtilis, which were cultured in liquid culture medium.

[0050] S5, Preparation of humic acid ammonia;

[0051] Weigh out humic acid, dilute it 1000 times with deionized water, add ammonia water with a volume of 20 times that of humic acid, place it in a container and sonicate for 8-12 minutes. React fully for 5.5-6.5 hours under magnetic stirring at 35-45℃, then cool to room temperature and precipitate for 10-14 hours. Pass the mixed solution through a cellulose membrane, filter out impurities and set aside. Then freeze-dry the mixed solution, dry it at a constant temperature of 90℃ to form a solid, and place it in the corresponding layer structure inside the membrane structure bag body 8.

[0052] S6. Microbial immobilization;

[0053] Biochar and bacterial suspensions of different particle sizes were mixed in an adsorption-immobilization method at a ratio of 1:3 to 1:30 (bacterial agent:biochar) and placed in Erlenmeyer flasks. The mixtures were incubated with shaking for 23-25 ​​hours, then centrifuged at 3500 rpm for 4-6 minutes, the supernatant was discarded, and the mixture was washed with sterile water before being dried in a vacuum freeze-drying oven for 23-25 ​​hours to obtain biochar with immobilized microorganisms. Biochar from kitchen waste with immobilized microorganisms of the same particle size was then mixed with ordinary biochar at a 1:1 ratio and placed in the corresponding layer structure inside the membrane structure bag body 8.

[0054] The aforementioned materials and the soil to be improved / remediated are placed layer by layer in the membrane structure, with one side of the membrane covering the top surface, and then sealed using a sealing machine. Before use, holes are randomly punched on the top surface of the membrane structure bag body 8 using needles with outer diameters of 0.5mm, 0.8mm, 1.6mm, and 3mm, allowing different types of organisms to enter and exit through different pore sizes. The spacing between the holes is greater than 1cm to maintain the membrane structure's shape.

[0055] The following specific experimental examples will further illustrate this point:

[0056] Seven treatments were designed for heavy metal pollution: no remediation for cadmium pollution (A), morning glory remediation (B), morning glory + Bacillus belysinus remediation (C), morning glory + lactic acid bacteria + yeast remediation (D), morning glory + Bacillus belysinus + multiple biochar membrane structures remediation (E), morning glory + lactic acid bacteria + yeast + multiple biochar membrane structures remediation (F), and morning glory + multiple biochar membrane structures remediation (G). The initial cadmium concentration was 15 mg / kg. Ten morning glories were planted per pot. The bacterial solution concentration was 2-30 × 10⁸ CFU / ml. The membrane structure consisted of 5g each of the following: large-particle high-temperature (800℃) ordinary biochar, large-particle low-temperature (400℃) ordinary biochar, small-particle high-temperature (800℃) ordinary biochar, small-particle low-temperature (400℃) ordinary biochar, large-particle high-temperature (800℃) kitchen waste biochar, large-particle low-temperature (400℃) kitchen waste biochar, small-particle high-temperature (800℃) kitchen waste biochar, small-particle low-temperature (400℃) kitchen waste biochar, morning glory droplets, and humic acid ammonia. The membrane pore sizes were 1 mm and 3 mm, and the membrane structure bag size was 8 cm × 8 cm. One membrane structure bag was placed in each pot.

[0057] like Figure 2 As shown, in the initial stage of the experiment Figure 2 Except for no repair (A), the effects of other treatments were not significantly different, with D and E showing slightly better growth than the other treatments. As time progressed, the differences between treatments became significant, with D, E, F, and G all showing good growth. Figure 2 This indicates that different types of microorganisms (fungi + bacteria) have better repair effects in microbial treatment, and the use of membrane structures can better support plant growth.

[0058] Regarding soil heavy metal removal and nutrient storage, in the first 20 days, all treatments reduced soil cadmium concentration, with the combined remediation treatment showing an even lower cadmium concentration, but the differences between treatments were not significant. The treatment containing *Bacillus belyceae* had higher organic carbon content because this bacterium can decompose organic matter and increase carbon content. The addition of membrane structures further increased soil organic carbon content, and the addition of kitchen waste and humic acid ammonia in the membrane structures inhibited excessively high soil carbon-to-nitrogen ratios, increasing nutrient availability. After 40 days, the combined remediation treatment showed more significant cadmium removal, with the morning glory + membrane structure + lactic acid bacteria + yeast treatment showing the highest removal rate. The soil organic carbon content with the added membrane structure was significantly higher than other treatments, while the soil carbon-to-nitrogen ratio remained within an appropriate range.

[0059] To address pesticide contamination, three treatments were designed: morning glory + Bacillus subtilis + membrane structure (Ethylene I), morning glory + Bacillus subtilis (Ethylene II), and morning glory + membrane structure (Ethylene III). The pesticide used was acetochlor, with an initial concentration of 50 mg / kg. The Bacillus subtilis concentration was 2-30 × 10⁸ CFU / ml. Each pot contained 15 morning glories. The membrane structure bags were treated in the same way as the heavy metal treatment.

[0060] The morning glory plants treated with Bacillus subtilis + membrane structure (BET I) showed the best growth, while the morning glory plants treated with Bacillus subtilis alone (BET II) showed the worst growth.

[0061] At 20 days, the acetochlor content in each treatment was not significantly different. At 40 days, the removal rate of acetochlor I was the highest, while that of acetochlor III was the lowest, indicating that the membrane structure combined with microorganisms can achieve the best acetochlor remediation effect.

[0062] All matters not covered in this invention are common knowledge.

[0063] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Various modifications and improvements made by those skilled in the art to the technical solutions of the present invention without departing from the spirit of the present invention should fall within the protection scope defined by the claims of the present invention.

Claims

1. A universal membrane structure bag, comprising a membrane structure bag body; characterized in that: The membrane structure bag body has nine layers arranged vertically from bottom to top. The bottom layer is a 5-10mm layer of soil to be improved / repaired as the first layer. The surface of the first layer is covered with biochar, humic ammonia and small particulate litter after microorganism fixation as the second layer. The second layer is covered with a 5-10mm thick layer of soil to be improved / remediated, serving as the third layer. The central area of ​​the third layer is filled with biochar, humic ammonia, and large-particle litter after microbial fixation, while the outer area is filled with biochar, humic ammonia, and small-particle litter after microbial fixation, serving as the fourth layer. The fourth layer is covered with a 5-10mm thick layer of soil to be improved / remediated, serving as the fifth layer. The sixth and seventh layers repeat the operation of the fourth and fifth layers, and the seventh and eighth layers repeat the operation of the second and third layers; the surface of the eighth layer is covered with 5-10mm of soil to be improved / repaired as the ninth layer; the top surface of the membrane structure bag body has holes of different diameters randomly opened.

2. The universal membrane structure bag according to claim 1, characterized in that: The membrane structure bag body is a biodegradable fiber membrane or plastic.

3. The method for preparing a universal membrane structure bag according to claim 2, characterized in that, The method includes the following steps: S1. Preparation of the membrane structure bag body; S2, Preparation of biochar; S3. Preparation of litter; S4. Cultivate microorganisms; S5, Preparation of humic acid ammonia; S6. Microbial immobilization.

4. The method for preparing a universal membrane structure bag according to claim 3, characterized in that, Step S2 includes: S2.1 Preparation of biochar from kitchen waste: Vegetables, fruit peels, food scraps, bone fragments, and eggshells and fruit pits are mixed evenly in a ratio of 50:20:20:5:5, crushed, and dried in an oven at 55-65℃ for 3.5-4.5 hours to obtain large particles of kitchen waste. These particles are then further crushed and passed through a 2mm sieve. The kitchen waste is then divided into two portions. One portion is subjected to anaerobic pyrolysis at 750-850℃ for 3.5-4.5 hours, then cooled to 55-65℃ and then to room temperature to obtain primary biochar. This primary biochar is then ground through a 100-mesh sieve. The other portion is subjected to anaerobic pyrolysis at 350-450℃ for 3.5-4.5 hours, then cooled to 55-65℃ and then to room temperature to obtain primary biochar. This primary biochar is then ground through a 60-mesh sieve. S2.2 Preparation of ordinary biochar: Corn stalks were crushed using a pulverizer and then subjected to anaerobic pyrolysis at 350-450℃, 550-650℃, and 750-850℃ for 3.5-4.5 hours, respectively. After the temperature was lowered to room temperature, the stalks were removed, ground, and passed through 60-mesh and 100-mesh sieves to obtain straw biochar with different particle sizes and pore sizes. Wood chips were crushed using a pulverizer and then carbonized. They were heat-treated at 550-650℃, 750-850℃, 950-1050℃, and 1250-1350℃ for 6.5-7.5 hours, respectively. After the temperature was lowered to room temperature, the wood chips were removed, ground, and passed through 60-mesh and 100-mesh sieves to obtain wood chip biochar with different particle sizes and pore sizes. Then, corn biochar and wood chip biochar of the same particle size were mixed separately.

5. The method for preparing a universal membrane structure bag according to claim 3, characterized in that, Step S3 includes: grinding fresh and lightly decomposed litter into powder, passing it through 18-mesh and 60-mesh sieves to obtain large-particle litter and small-particle litter, respectively.

6. The method for preparing a universal membrane structure bag according to claim 3, characterized in that, Step S4 includes: selecting actinomycetes, fascicular mycorrhizal fungi, and Bacillus subtilis as basic microorganisms, and culturing the bacteria in a liquid culture medium.

7. The method for preparing a universal membrane structure bag according to claim 3, characterized in that, Step S5 includes: weighing humic acid, diluting it 1000 times with deionized water, adding ammonia water with a volume of 20 times that of humic acid, placing it in a container and ultrasonically vibrating for 8-12 minutes, reacting fully for 5.5-6.5 hours under magnetic stirring at 35-45°C, then cooling to room temperature and precipitating for 10-14 hours, passing the mixed solution through a cellulose membrane, filtering out impurities and setting it aside for later use; then freeze-drying the mixed solution and drying it at a constant temperature of 90°C to form a solid.

8. The method for preparing a universal membrane structure bag according to claim 3, characterized in that, Step S6 includes: using an adsorption fixation method, mixing biochar and bacterial suspension of different particle sizes in a ratio of bacterial agent to biochar of 1:3-1:30 and placing them in an Erlenmeyer flask, shaking and culturing for 23-25 ​​hours, then centrifuging at 3500 rpm for 4-6 minutes to discard the supernatant, washing with sterile water and then placing it in a vacuum freeze dryer for drying for 23-25 ​​hours to obtain biochar with fixed microorganisms.

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