A composite soil remediation material, its preparation method and application

Abstract

The present invention relates to the technical field of soil remediation, and specifically discloses a composite soil remediation material, a preparation method thereof, and an application. The composite soil remediation material comprises the following raw material components in parts by mass: 15-25 parts of schwertmannite loaded with microbial liquid, 5-10 parts of biosurfactant, 10-20 parts of edible mushroom residue, 20-30 parts of natural mineral material, 1-5 parts of bicarbonate, and 70-80 parts of water; wherein, the microbial liquid comprises Arthrobacter globiformis, Serratia rubidaea, and Pichia anomala. The technical solution of the present invention effectively solves the problems in the prior art that the remediation of saline-alkali soil has high remediation cost, long time, strict application conditions, easy occurrence of secondary pollution, and poor remediation effect.

Description

Technical Field

[0001] The present invention relates to the technical field of soil remediation, and specifically discloses a composite soil remediation material, a preparation method thereof, and an application thereof. Background Art

[0002] Saline-alkali land refers to a type of land where the soil contains excessive soluble salts (such as sodium chloride, sodium sulfate, sodium carbonate, etc.) and alkaline substances (such as sodium carbonate, sodium bicarbonate, etc.), resulting in the deterioration of the physical and chemical properties of the soil and affecting the normal growth and development of plants. The existence of saline-alkali land not only causes waste of land resources but also brings many negative impacts on the local ecological environment, agricultural production, and economic development, such as low vegetation coverage, decreased land productivity, increased soil erosion, and reduced biodiversity. Therefore, carrying out research and practice on the remediation of saline-alkali land soil has important practical significance and strategic value.

[0003] In the prior art, the remediation of saline-alkali land soil includes physical remediation methods, chemical remediation methods, and biological remediation methods. Physical remediation methods include deep plowing and turning, irrigation and drainage projects, and soil replacement remediation, etc., but the labor cost is high and the effect is minimal; chemical remediation methods mainly involve applying chemical drugs to remediate saline-alkali land soil, such as gypsum, ferrous sulfate, or composite soil remediation agents. Although it has a certain remediation effect, it needs to be applied multiple times, resulting in a high cost of the agent, and it is easy to cause the accumulation of heavy metal ions in the soil, posing a potential hazard to the soil ecological environment. Biological remediation methods mainly involve remediating by planting salt-tolerant plants or applying microbial agents. Planting salt-tolerant plants has good ecological and economic benefits and can improve the ecological environment of the soil, but the remediation effect is slow and it takes a long time to reflect the remediation effect. Microbial agents have the advantages of high efficiency, environmental protection, and no secondary pollution, and can act synergistically with other remediation measures to improve the soil remediation effect and the growth performance of plants. However, their effect is greatly affected by soil environmental conditions (such as temperature, humidity, salinity, pH value, etc.), and the survival and reproduction of microbial agents require suitable substrates and living spaces, and in practical applications, reasonable selection and optimization of the usage method need to be carried out according to the soil conditions and plant requirements.

[0004] Therefore, it is of great practical significance to develop a soil remediation material with lower cost and better remediation effect for the remediation of saline-alkali land soil. Summary of the Invention

[0005] In view of the problems in the prior art that the remediation of saline-alkali soil has high remediation costs, long time, strict application conditions, prone to secondary pollution and poor remediation effects, the present invention provides a composite soil remediation material, its preparation method and application. The composite soil remediation material includes schwertmannite loaded with microbial liquid, biosurfactant, edible mushroom residue, natural mineral material, bicarbonate and water; wherein, the microbial liquid includes Arthrobacter globiformis, Serratia rubidaea and Pichia anomala. By utilizing the synergistic effect of each component, the composite soil remediation material is endowed with high remediation ability; more importantly, the composite soil remediation material is convenient to apply and not prone to secondary pollution, providing a new idea for the remediation of saline-alkali soil.

[0006] In order to achieve the above invention purpose, the present invention provides the following technical solutions:

[0007] The first aspect of the present invention provides a composite soil remediation material, which includes the following raw material components in parts by mass: 15-25 parts of schwertmannite loaded with microbial liquid, 5-10 parts of biosurfactant, 10-20 parts of edible mushroom residue, 20-30 parts of natural mineral material, 1-5 parts of bicarbonate and 70-80 parts of water; wherein, the microbial liquid includes Arthrobacter globiformis, Serratia rubidaea and Pichia anomala.

[0008] The present invention loads the microbial liquid on the surface of schwertmannite. By utilizing the good adsorption performance and large specific surface area of schwertmannite, the microorganisms loaded on its surface can be in a relatively stable environment, providing physical protection for the microorganisms and avoiding interference of the complex soil environment on the microorganisms. Moreover, schwertmannite can adsorb and store phosphorus, nitrogen, iron and other influencing elements from the soil as the nutrient supply for the microorganisms, which helps the microbial liquid maintain metabolic activity for a long time.

[0009] The said microbial inoculum can repair saline-alkali soil well. Among them, the cells of Arthrobacter globiformis have a certain osmotic pressure regulation mechanism. In a high-salt environment, Arthrobacter globiformis can absorb the salts in the soil into the cells, reduce the salt content in the soil, and then use its own metabolic activities to mutually transform the absorbed salt ions, thereby reducing the soil alkalinity. The cells of Serratia rubidaea avoid carrying charges and can adsorb harmful salt ions such as sodium ions in the soil through ion exchange, fix the salt ions on the cell surface, and reduce their concentration in the soil. Moreover, Serratia rubidaea can improve the soil structure, increase the soil porosity, and enable the salts to be discharged from the soil along with the water flow; acidic substances will be produced during its metabolism, which can neutralize the soil alkalinity and reduce the soil pH value. Pichia anomala will produce organic acids during its growth and metabolism. These organic acids can neutralize the alkaline components in the soil and reduce the degree of soil salinization. In addition, Pichia anomala can activate the soil salts, decompose the organic substances in the soil, release the nutrient elements required for plant growth, and can also secrete plant growth hormones, stimulate the growth and development of plant roots, and improve the tolerance of plants to saline-alkali environments.

[0010] The addition of biosurfactants can reduce the binding force between soil particles and salt ions, make the salts more easily dissolved and eluted, prevent soil compaction caused by salt accumulation, reduce the tight packing of the soil, help improve the metabolic growth of the microbial inoculum, and improve the repair performance of the composite soil repair material. More importantly, biosurfactants can improve the absorption efficiency of plants for water and nutrients, help plants relieve saline-alkali stress, and improve the adaptability of plants to saline-alkali environments. And edible mushroom residues can provide a large amount of nutrients for plant growth, supplement soil fertility, and promote the growth of plants in saline-alkali soil. Moreover, the residues provide rich carbon sources for soil microorganisms, can promote the growth and reproduction of soil microorganisms, help improve the soil properties and structure, and improve the soil texture.

[0011] Natural mineral materials have a large specific surface area and abundant surface charges, and can adsorb salt ions in the soil through ion exchange, reducing the salt concentration in the soil. Natural mineral materials can also play a role in supporting and loosening the soil, helping to improve the air permeability and water permeability of the soil, and facilitating the leaching of salts. Bicarbonate hydrolyzes in the soil environment to produce carbon dioxide, and the carbon dioxide escapes from the soil pores, helping to loosen the soil, increase the soil porosity, and improve the air permeability and water permeability of the soil.

[0012] In summary, the present invention utilizes the synergistic effect of each component raw material to provide a composite soil remediation material with high-efficiency saline-alkali soil remediation. Using the composite soil remediation material can effectively solve the problems of high remediation cost, long time, strict application conditions, easy occurrence of secondary pollution, and poor remediation effect in the existing technology for saline-alkali soil remediation, providing a new design idea for the remediation of saline-alkali soil.

[0013] Preferably, the viable cell number ratio of Arthrobacter globiformis, Serratia rubidaea, and Pichia anomala in the microbial liquid is 1:1:0.8 - 1:1:1, and the viable cell concentration in the microbial liquid is (1×10 9 ) CFU / mL - (1×10 10 ) CFU / mL.

[0014] Preferably, the preservation number of Arthrobacter globiformis is BNCC139139.

[0015] Preferably, the preservation number of Serratia rubidaea is BNCC364420.

[0016] Preferably, the preservation number of Pichia anomala is BNCC186318.

[0017] Preferably or further preferably, the preparation method of the schwertmannite loaded with microbial liquid comprises the following steps:

[0018] S1. Filter the acid mine drainage, add an oxidant to the filtrate, carry out an oxidation reaction, adjust the pH to 2 - 4, filter to obtain a brownish-yellow solid; wash the brownish-yellow solid 3 - 5 times with acid, dry, and grind to obtain schwertmannite;

[0019] S2. Mix the cultured Arthrobacter globiformis, the cultured Serratia rubidaea, and the cultured Pichia anomala evenly according to the designed ratio to obtain a microbial liquid;

[0020] S3. Disperse the schwertmannite in a buffer solution, adjust the pH to 5 - 7, slowly add the microbial liquid, mix evenly, stir at a speed of 100 rpm - 200 rpm for 6 h - 8 h, carry out solid-liquid separation, and dry naturally to obtain the schwertmannite loaded with microbial liquid.

[0021] Further preferably, in S1, the oxidant is a hydrogen peroxide solution with a mass fraction of 20% - 35%.

[0022] Further preferably, in S1, the mass ratio of the oxidant to the filtrate is 1:4 - 1:6.

[0023] Further preferably, in S1, the temperature of the oxidation reaction is 80°C - 90°C, and the time of the oxidation reaction is 8 h - 10 h.

[0024] More preferably, in S1, a strong base is used to adjust the pH to 2-4.

[0025] More preferably, in S1, the pickling uses a sulfuric acid solution with a concentration of 0.5 mol / L - 1 mol / L as the washing liquid.

[0026] More preferably, in S1, the drying temperature is 85°C - 100°C, and the drying time is 6h - 10h.

[0027] More preferably, in S3, the mass-volume ratio of the schwertmannite to the buffer solution is 1g:3mL - 1g:5mL.

[0028] More preferably, in S3, the buffer solution is a phosphate buffer solution.

[0029] More preferably, in S3, the mass-volume ratio of the schwertmannite to the microbial inoculum is 1g:1mL - 1g:2mL.

[0030] Preferably, the biosurfactant includes rhamnolipid and trehalolipid with a mass ratio of 1:0.1 - 1:0.2.

[0031] Preferably, the edible mushroom residue includes any one or more of Pleurotus eryngii residue, Pleurotus ostreatus residue, or Lentinula edodes residue.

[0032] Preferably, the natural mineral material is zeolite and fly ash with a mass ratio of 1:2 - 1:3.

[0033] More preferably, the particle size of the natural mineral material is 100μm - 200μm.

[0034] The second aspect of the present invention provides a preparation method of the composite soil remediation material, comprising the following steps:

[0035] Weigh the schwertmannite loaded with microbial inoculum, edible mushroom residue, and natural mineral material according to the designed ratio, mix them evenly to obtain a solid mixture; weigh the remaining components according to the designed ratio, mix them evenly to obtain a liquid mixture; mix the solid mixture and the liquid mixture evenly to obtain the composite soil remediation material.

[0036] The third aspect of the present invention provides the application of the composite soil remediation material in the field of saline-alkali soil remediation.

[0037] Preferably, the release amount of the composite soil remediation material is 30 kg / mu - 35 kg / mu.

[0038] Preferably, the water content of the saline-alkali soil is 65% - 85%.

[0039] In summary, the present invention provides a composite soil remediation material, a preparation method thereof, and an application thereof. By utilizing the synergistic effect of each component raw material, the composite soil remediation material has the ability to efficiently remediate saline-alkali soil; moreover, the application conditions of the composite soil remediation material are simple, the remediation cost is low, and secondary pollution is not likely to occur. By using the composite soil remediation material, the problems existing in the remediation of saline-alkali soil in the prior art, such as high remediation cost, long time, strict application conditions, easy occurrence of secondary pollution, and poor remediation effect, can be effectively solved, providing a new idea for the remediation of saline-alkali soil. Detailed Embodiments

[0040] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Apparently, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0041] The specific preparation methods of the microbial inoculum used in each example and comparative example are as follows:

[0042] Arthrobacter globiformis was inoculated on a nutrient broth medium and activated at 28 °C for 30 h to obtain an activated strain; then, a single colony after activation was picked and inoculated into a seed medium, and secondary seed culture was carried out at 28 °C and an oscillation speed of 150 rpm for 30 h to obtain a seed solution; the seed solution was inoculated into a fermentation medium at a ratio of 8% by volume and fermented at 28 °C until the viable cell count reached 1×10 9 CFU / mL.

[0043] Among them, the formula of the nutrient broth medium is: peptone 10 g, beef extract 3 g, sodium chloride 5 g, agar 15 g, and water 1000 mL; the pH of the nutrient broth medium is 7.1.

[0044] The formula of the seed medium is: peptone 10 g, beef extract 3 g, sodium chloride 5 g, and water 1000 mL, and the pH of the seed medium is 7.1.

[0045] The formula of the fermentation medium is: glucose 20 g, yeast extract 10 g, potassium dihydrogen phosphate 3 g, magnesium sulfate 1.5 g, sodium chloride 5 g, and water 1000 mL, and the pH of the fermentation medium is 7.1.

[0046] Inoculate Serratia rubidaea on LB solid medium and activate it by culturing at 30°C for 24 h to obtain activated strains. Then pick the activated single colonies and inoculate them into the liquid seed medium, and perform secondary seed culture at 30°C and an oscillation speed of 180 rpm for 20 h to obtain the seed liquid. Inoculate the said seed liquid into the fermentation medium at an inoculation amount of 8% of the volume ratio of the fermentation medium, and perform fermentation culture at 30°C and an oscillation speed of 180 rpm until the viable cell count reaches 1×10 9 CFU / mL.

[0047] Among them, the formula of the LB solid medium is: 10 g of peptone, 5 g of yeast extract, 10 g of sodium chloride, 15 g of agar and 1000 mL of water; the pH of the nutrient broth medium is 7.3.

[0048] The formula of the liquid seed medium is: 20 g of peptone, 10 g of sodium chloride, 10 g of yeast extract powder and 1000 mL of water; the pH of the liquid seed medium is 7.3.

[0049] The formula of the fermentation medium is: 20 g of glucose, 10 g of yeast extract, 3 g of potassium dihydrogen phosphate, 1.5 g of magnesium sulfate, 5 g of sodium chloride and 1000 mL of water, and the pH of the fermentation medium is 7.1.

[0050] Inoculate Pichia anomala on the activation medium and activate it by culturing at 30°C for 36 h to obtain the activated bacterial liquid. Under aseptic conditions, inoculate the activated bacterial liquid into the seed medium at an inoculation amount of 3% of the volume ratio of the seed medium, and perform secondary seed culture at 30°C and an oscillation speed of 150 rpm for 20 h to obtain the seed liquid. Inoculate the said seed liquid into the fermentation medium at an inoculation amount of 8% of the volume ratio of the fermentation medium, and perform fermentation culture at 28°C, a stirring speed of 200 rpm and an aeration rate of 1.5 vvm until the viable cell count reaches 1×10 9 CFU / mL.

[0051] Among them, the formula of the activation medium is: 20 g of peptone, 20 g of glucose, 10 g of yeast powder and 1000 mL of water; the pH of the activation medium is 6.0.

[0052] The formula of the seed medium is: 20 g of peptone, 20 g of glucose, 10 g of yeast powder and 1000 mL of water; the pH of the seed medium is 6.0.

[0053] The formula of the fermentation medium is: 30 g of phosphoric acid, 1.5 g of calcium sulfate, 30 g of potassium chloride, 3.5 g of potassium hydroxide, 100 g of glucose, 40 g of magnesium sulfate heptahydrate, 2.0 g of ammonium sulfate, 1.5 g of casein, 4.0 g of tryptone and 1000 mL of water, and the pH of the fermentation medium is 6.5.

[0054] Example 1

[0055] This example provides a composite soil remediation material and its preparation method, including the following mass components: 20 parts of schwertmannite loaded with microbial liquid, 8 parts of biosurfactant, 15 parts of lentinus edodes residue, 25 parts of natural mineral material, 3 parts of sodium bicarbonate, and 75 parts of water.

[0056] Among them, the biosurfactant is a mixture of rhamnolipid and trehalose lipid with a mass ratio of 1:0.1; the natural mineral material is a mixture of zeolite with a particle size of 150 μm and fly ash, and the mass ratio of zeolite to fly ash is 1:2.5.

[0057] Weigh the schwertmannite loaded with microbial liquid, lentinus edodes residue, and natural mineral material according to the designed ratio, mix them evenly to obtain a solid mixture; weigh the remaining components according to the designed ratio, mix them evenly to obtain a liquid mixture; mix the solid mixture and the liquid mixture evenly to obtain the composite soil remediation material.

[0058] Among them, the preparation method of the schwertmannite loaded with microbial liquid includes the following steps:

[0059] S1. Filter 1 L of acidic mine wastewater, add 200 mL of hydrogen peroxide solution with a mass fraction of 25% to the filtrate, carry out an oxidation reaction at 85 °C for 8 h, adjust the pH to 3.1 with sodium hydroxide, let it stand for precipitation, filter to obtain a brownish-yellow solid; wash the brownish-yellow solid 4 times with a sulfuric acid solution with a concentration of 0.8 mol / L, dry it at 90 °C for 8 h, and grind it to obtain schwertmannite.

[0060] S2. Mix the expanded Arthrobacter globiformis, the expanded Serratia rubidaea, and the expanded Pichia anomala evenly according to a mass ratio of 1:1:0.9 to obtain a microbial liquid.

[0061] S3. Disperse 200 g of the schwertmannite in 1 L of phosphate buffer, adjust the pH to 6.2, slowly add the microbial liquid, mix evenly, stir at a speed of 150 rpm for 7 h, centrifuge, discard the liquid, and dry it naturally to obtain the schwertmannite loaded with microbial liquid.

[0062] Example 2

[0063] This example provides a composite soil remediation material and its preparation method, including the following mass components: 25 parts of schwertmannite loaded with microbial liquid, 10 parts of biosurfactant, 20 parts of pleurotus ostreatus residue, 30 parts of natural mineral material, 5 parts of sodium bicarbonate, and 80 parts of water.

[0064] Among them, the biosurfactant is rhamnolipid and trehalose lipid with a mass ratio of 1:0.2; the natural mineral material is a mixture of zeolite and fly ash with a particle size of 200 μm, and the mass ratio of zeolite to fly ash is 1:2.

[0065] Weigh the schwertmannite loaded with microbial liquid, lentinus edodes residue, and natural mineral material according to the designed ratio, mix them evenly to obtain a solid mixture; weigh the remaining components according to the designed ratio, mix them evenly to obtain a liquid mixture; mix the solid mixture and the liquid mixture evenly to obtain a composite soil remediation material.

[0066] Among them, the preparation method of the schwertmannite loaded with microbial liquid includes the following steps:

[0067] S1. Filter 1 L of acid mine drainage, add 200 mL of hydrogen peroxide solution with a mass fraction of 25% to the filtrate, carry out an oxidation reaction at 85 °C for 8 h, adjust the pH to 3.1 with sodium hydroxide, let it stand for precipitation, filter to obtain a brownish-yellow solid; wash the brownish-yellow solid 4 times with a sulfuric acid solution with a concentration of 0.8 mol / L, dry it at 90 °C for 8 h, and grind it to obtain schwertmannite.

[0068] S2. Mix the expanded Arthrobacter globiformis, the expanded Serratia rubidaea, and the expanded Pichia anomala evenly according to a mass ratio of 1:1:0.9 to obtain a microbial liquid.

[0069] S3. Disperse 200 g of the schwertmannite in 1 L of phosphate buffer, adjust the pH to 6.2, slowly add the microbial liquid, mix evenly, stir at a speed of 150 rpm for 7 h, centrifuge, discard the liquid, and dry it naturally to obtain the schwertmannite loaded with microbial liquid.

[0070] Example 3

[0071] This example provides a composite soil remediation material and its preparation method, including the following mass components: 15 parts of schwertmannite loaded with microbial liquid, 5 parts of biosurfactant, 10 parts of lentinus edodes residue, 20 parts of natural mineral material, 2 parts of sodium bicarbonate, and 70 parts of water.

[0072] Among them, the biosurfactant is rhamnolipid and trehalose lipid with a mass ratio of 1:0.1; the natural mineral material is a mixture of zeolite and fly ash with a particle size of 100 μm, and the mass ratio of zeolite to fly ash is 1:3.

[0073] Weigh the schwertmannite loaded with microbial liquid, lentinus edodes residue, and natural mineral material according to the designed ratio, mix them evenly to obtain a solid mixture; weigh the remaining components according to the designed ratio, mix them evenly to obtain a liquid mixture; mix the solid mixture and the liquid mixture evenly to obtain a composite soil remediation material.

[0074] Among them, the preparation method of the schwertmannite loaded with microbial liquid comprises the following steps:

[0075] S1. Filter 1 L of acidic mine wastewater, add 200 mL of hydrogen peroxide solution with a mass fraction of 25% to the filtrate, carry out an oxidation reaction at 85 °C for 8 h, adjust the pH to 3.1 with sodium hydroxide, let it stand for precipitation, filter, and obtain a brownish-yellow solid; Pickle the brownish-yellow solid 4 times with a sulfuric acid solution with a concentration of 0.8 mol / L, dry it at 90 °C for 8 h, and grind it to obtain schwertmannite;

[0076] S2. Mix the expanded Arthrobacter sphaeroides, the expanded Serratia rubidaea, and the expanded Pichia anomala evenly according to a mass ratio of 1:1:0.9 to obtain a microbial liquid;

[0077] S3. Disperse 200 g of the schwertmannite in 1 L of phosphate buffer, adjust the pH to 6.2, slowly add the microbial liquid, mix evenly, stir at a speed of 150 rpm for 7 h, centrifuge, discard the liquid, and dry it naturally to obtain the schwertmannite loaded with microbial liquid.

[0078] Comparative Example 1

[0079] This comparative example provides a composite soil remediation material and its preparation method. The difference from Example 1 is that the Arthrobacter sphaeroides in the microbial liquid is replaced with an equal amount of Burkholderia sp., and other components and processes remain unchanged, which will not be elaborated here.

[0080] The preparation method of the Burkholderia sp. liquid comprises the following content:

[0081] Inoculate Burkholderia sp. on a nutrient broth medium, carry out activation culture at 28 °C for 30 h to obtain an activated strain; Then pick a single colony after activation and inoculate it into a seed medium, carry out secondary seed culture at 28 °C and an oscillation speed of 150 rpm for 30 h to obtain a seed liquid; Inoculate the seed liquid into a fermentation medium according to a volume ratio of 8%, and ferment and culture at a temperature of 28 °C until the viable bacteria count reaches 1×10 9 CFU / mL.

[0082] Among them, the formula of the nutrient broth medium is: 10 g of peptone, 3 g of beef extract, 5 g of sodium chloride, 15 g of agar, and 1000 mL of water; The pH of the nutrient broth medium is 7.1.

[0083] The formula of the seed medium is: 10 g of peptone, 3 g of beef extract, 5 g of sodium chloride, and 1000 mL of water, and the pH of the seed medium is 7.1.

[0084] The formulation of the fermentation medium is as follows: 20 g of glucose, 10 g of yeast extract, 3 g of potassium dihydrogen phosphate, 1.5 g of magnesium sulfate, 5 g of sodium chloride, and 1000 mL of water. The pH of the fermentation medium is 7.1.

[0085] Comparative Example 2

[0086] This comparative example provides a composite soil remediation material and its preparation method. The difference from Example 1 is that the Serratia rubidaea in the microbial liquid is replaced with an equal amount of Bacillus megaterium, and other components and processes remain unchanged, which will not be elaborated here.

[0087] The preparation method of the Bacillus megaterium liquid includes the following steps:

[0088] Inoculate Bacillus megaterium on a nutrient broth medium and perform activation culture at 28 °C for 30 h to obtain activated strains. Then pick the activated single colonies and inoculate them into a seed medium, and perform secondary seed culture at 28 °C and an oscillation speed of 150 rpm for 30 h to obtain a seed liquid. Inoculate the seed liquid into a fermentation medium at a ratio of 8% by volume and ferment at 28 °C until the viable cell count reaches 1×10 9 CFU / mL.

[0089] Among them, the formulation of the nutrient broth medium is: 10 g of peptone, 3 g of beef extract, 5 g of sodium chloride, 15 g of agar, and 1000 mL of water; the pH of the nutrient broth medium is 7.1.

[0090] The formulation of the seed medium is: 10 g of peptone, 3 g of beef extract, 5 g of sodium chloride, and 1000 mL of water. The pH of the seed medium is 7.1.

[0091] The formulation of the fermentation medium is: 20 g of glucose, 10 g of yeast extract, 3 g of potassium dihydrogen phosphate, 1.5 g of magnesium sulfate, 5 g of sodium chloride, and 1000 mL of water. The pH of the fermentation medium is 7.1.

[0092] Comparative Example 3

[0093] This comparative example provides a composite soil remediation material and its preparation method. The difference from Example 1 is that the schwertmannite loaded with the microbial liquid is replaced with an equal amount of schwertmannite, and other components and the preparation method remain unchanged, which will not be elaborated here.

[0094] Performance Test

[0095] The composite soil remediation materials obtained from each example and comparative example were used in saline-alkali soil. After the soil was rotary tilled, it was irrigated and drained. When the soil moisture content was 75%-80%, the composite soil remediation materials were applied at a rate of 30 kg per mu. After 10 days of remediation, peanuts were planted in the experimental field. The land was prepared by local conventional methods, and the peanut variety was Luhua No. 9. All treatments were prepared for land at the same time and sown at the same time. After sowing, local conventional field management was adopted. After the peanuts were harvested, the peanut yields of different treatments were counted, and the salt content, pH value, organic matter content, and soil particle size percentage at 0-20 cm of the soil were measured. The results are shown in Table 1.

[0096] Table 1 Comparison of organic matter content before and after remediation of composite soil remediation materials obtained from each example and comparative example

[0097]

[0098] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, or improvements made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A composite soil remediation material, characterized in that: The method comprises the following raw material components in parts by weight: 15-25 parts of Schmidt mineral loaded with microbial liquid, 5-10 parts of biological surfactant, 10-20 parts of edible fungus residue, 20-30 parts of natural mineral material, 1-5 parts of bicarbonate and 70-80 parts of water; wherein the microbial liquid comprises Arthrobacter sphaeroides, Serratia rubrum and Pichia anomala; The ratio of the number of live bacteria of Arthrobacter sphaeroides, Serratia rubra and Pichia anomala in the microbial liquid is 1:1:0.8-1:1:1, and the concentration of live bacteria in the microbial liquid is (1×10 8 )CFU / mL-(1×10 9 )CFU / mL.

2. The composite soil remediation material according to claim 1, characterized in that: The preparation method of the Schmidt mineral loaded with microbial liquid comprises the following steps: S1, filtering the acid mine wastewater, adding an oxidant to the filtrate, carrying out an oxidation reaction, adjusting the pH to 2-4, filtering, and obtaining a brown-yellow solid; acid-washing the brown-yellow solid 3-5 times, drying, and grinding to obtain Schmidtite; S2, mixing the cultured Arthrobacter sphaeroides, the cultured Serratia rubrum and the cultured Pichia anomala according to the designed ratio to obtain a microbial culture solution; S3, dispersing the Schreiber mineral in a buffer solution, adjusting the pH to 5-6, slowly adding the microbial solution, mixing evenly, stirring at a speed of 100-200 rpm for 6-8 hours, separating the solid and the liquid, and drying naturally to obtain the Schreiber mineral loaded with the microbial solution.

3. The composite soil remediation material according to claim 2, characterized in that: In S1, the oxidant is a hydrogen peroxide solution with a mass fraction of 20%-35%; and / or In S1, the mass ratio of the oxidant to the filtrate is 1:4-1:6; and / or In S1, the temperature of the oxidation reaction is 80°C-90°C, and the time of the oxidation reaction is 8h-10h.

4. The composite soil remediation material according to claim 2, characterized in that: In S3, the mass volume ratio of the Schroeder mineral to the buffer solution is 1 g:3 mL-1 g:5 mL; and / or In S3, the mass volume ratio of the Schreiber mineral to the microbial liquid is 1 g:1 mL-1 g:2 mL.

5. The composite soil remediation material according to claim 1, characterized in that: The biosurfactant comprises rhamnolipid and trehalose lipid in a mass ratio of 1:0.1-1:0.2; and / or The edible fungus residue includes any one or more of Pleurotus eryngii residue, Pleurotus ostreatus residue or Lentinus edodes residue; and / or The natural mineral materials are zeolite and fly ash in a mass ratio of 1:2-1:

3.

6. The method for preparing the composite soil remediation material according to any one of claims 1 to 5, characterized in that: The steps include: According to the designed ratio, Schmidt mineral loaded with microbial liquid, edible fungus residue, and natural mineral material are weighed and mixed evenly to obtain a solid mixture; according to the designed ratio, the remaining components are weighed and mixed evenly to obtain a liquid mixture; the solid mixture and the liquid mixture are mixed evenly to obtain a composite soil remediation material.

7. Use of the composite soil remediation material according to any one of claims 1 to 5 in the field of saline-alkali soil remediation.

8. The use of the composite soil remediation material according to claim 7 in the field of saline-alkali soil remediation, characterized in that: The release amount of the composite soil remediation material is 30kg / mu-35kg / mu; and / or The water content of the saline-alkali soil is 65%-85%.

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