Red mud soil treatment composition as well as preparation method and application thereof

Abstract

The invention provides a red mud soil composition and a preparation method and application thereof.The preparation method comprises the following steps that 1, EM bacteria, part of molasses, shelled eggs, pure rice vinegar, red mud, 17-17-17 nitrogen-phosphorus-potassium compound fertilizer and part of water are mixed to be uniform, then semi-closed fermentation is conducted for 70-75 h, and a material A is obtained; (2) uniformly mixing the material A, part of molasses and part of water, and then performing semi-closed fermentation for 70-75h to obtain a material B; (3) mixing the material B, beef peptide, soybean peptide, residual molasses and residual water, and performing sealed fermentation for 48-55 days to obtain a material C; and (4) adding granular active carbon into the material C, soaking until the temperature of the system is raised, then filtering and reserving filter residues, then mixing rice bran, potassium fulvate, diammonium phosphate and crushed agricultural and forestry straws, and fermenting at room temperature in a semi-closed environment for 70-75 hours to obtain the red mud soil composition. According to the preparation method, the prepared red mud soil composition can be directly applied to red mud through induction culture of the EM bacteria, and soil modification is carried out on the red mud.

Description

Technical Field

[0001] The invention belongs to the technical field of red mud soilification, and specifically relates to a red mud soilification composition and a preparation method and application thereof. Background Art

[0002] Red mud, as an inevitable byproduct of the process of refining alumina from bauxite, has become an important topic in the field of environmental science. China, as the world's leading country in alumina production, produces millions of tons of red mud every year. The discharge of these wastes not only occupies a large amount of land resources, but also causes serious pollution to the surrounding environment. Harmful substances contained in red mud, such as heavy metals and other toxic elements, pose a long-term threat to soil and water quality, and thus affect the health of the ecosystem and human health.

[0003] In order to solve this problem, the international community has proposed a strategy to convert red mud into a soil-like matrix for plant growth. This conversion can not only reduce the accumulation of red mud and reduce environmental risks, but also provide a medium for plant growth and achieve resource recycling. However, the extreme physical and chemical properties of red mud pose challenges to this conversion process. The high alkalinity, high salinity and lack of nutrients of red mud make it difficult for many conventional pioneer plants and microorganisms to survive and reproduce on it. These organisms are usually key players in the soilification process. They promote soil formation and improvement by decomposing organic matter, fixing nitrogen and improving soil structure. But these characteristics of red mud limit the activities of these organisms, thereby hindering the soilification process of red mud dumps. Summary of the invention

[0004] One of the purposes of the present invention is to overcome the above technical defects and provide a red mud soil composition.

[0005] Another object of the present invention is to provide a method for preparing the red mud soil composition.

[0006] Another object of the present invention is to provide an application of the red mud soil composition.

[0007] The technical solution of the present invention is as follows:

[0008] A method for preparing a red mud soil composition comprises the following steps:

[0009] (1) mixing EM bacteria, part of molasses, shelled eggs, pure brewed rice vinegar, red mud, 17-17-17 nitrogen, phosphorus and potassium compound fertilizer and part of water, and then fermenting at room temperature for 70-75 hours in a semi-closed environment, during which the system temperature is controlled not to exceed 40° C., to obtain material A;

[0010] (2) mixing the above-mentioned material A, part of the above-mentioned molasses and part of the water, and then fermenting at room temperature for 70-75 hours in a semi-closed environment, during which the system temperature is controlled not to exceed 40° C., to obtain material B;

[0011] (3) Mixing the above-mentioned material B, beef peptide, soybean peptide, the remaining molasses and the remaining water, and fermenting at room temperature for 48-55 days in a closed environment, during which the system temperature is controlled not to exceed 40° C., to obtain material C;

[0012] (4) adding granular activated carbon to the above-mentioned C material, soaking until the system temperature rises, then filtering and retaining the filter residue, and then mixing the above-mentioned filter residue, rice bran, potassium humate, diammonium phosphate and agricultural and forestry straw crushed material, and fermenting them at room temperature for 70-75 hours in a semi-closed environment to obtain a red mud soil composition;

[0013] The mass volume ratio of the above-mentioned EM bacteria, molasses, shelled eggs, pure brewed rice vinegar, red mud, 17-17-17 nitrogen, phosphorus and potassium compound fertilizer, beef peptide, soybean peptide and water is 190-210L: 55-65kg: 0.8-1.2kg: 0.8-1.2kg: 4-6kg: 18-22kg: 9-11kg: 9-11kg: 780-820kg;

[0014] The ratio of the amount of molasses added in step (1), step (2) and step (3) is 0.8-1.2:1.8-2.2:2.8-3.2, and the ratio of the amount of water added in step (1), step (2) and step (3) is 0.8-1.2:2.8-3.2:3.8-4.2;

[0015] The mass ratio of the filter residue, the granular activated carbon, the rice bran, the potassium humate, the diammonium phosphate and the crushed agricultural and forestry straw is 950-1050: 0.8-1.2: 4.8-5.2: 0.8-1.2: 0.8-1.2: 95-105.

[0016] In some preferred implementations, the room temperature fermentation operation further includes: stirring for 25-40 minutes every 10-12 hours.

[0017] In some preferred implementations, the ambient temperature of room temperature fermentation is 5-40°C.

[0018] Further preferably, the ambient temperature of room temperature fermentation is 26-28°C.

[0019] In some preferred implementations, the soaking time in step (4) is 20-40 minutes.

[0020] A red mud soil composition is prepared by the above preparation method.

[0021] A method for soilification of red mud comprises the following steps: adding the red mud soilification composition obtained by the above preparation method into red mud, and then fermenting it at room temperature for 70-75 hours in a semi-closed environment.

[0022] In some preferred implementations, the amount of the red mud soilification composition added is 0.1-10 wt %.

[0023] The present invention has at least the following beneficial effects:

[0024] The preparation method provided by the invention enables the prepared red mud soil composition to be directly applied to red mud and perform soil modification on the red mud through induction culture of EM bacteria. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 is a photo of the red mud used in the examples of the present invention;

[0026] Figure 2 is a photo of the red mud used in the examples of the present invention;

[0027] Figure 3 The fermentation condition of the red mud soil composition prepared in Example 1 of the present invention after being added with red mud is shown;

[0028] Figure 4 The fermentation condition of the red mud soil composition prepared in Example 1 of the present invention after being added with red mud is shown;

[0029] Figure 5 The survival of grass seeds and green plants planted after the red mud soil composition prepared in Example 1 of the present invention is added with red mud is shown;

[0030] Figure 6 The survival of grass seeds planted after the red mud soil composition prepared in Example 1 of the present invention was added to red mud;

[0031] Figure 7 The survival of green plants planted after the red mud soil composition prepared in Example 1 of the present invention is added with red mud is shown;

[0032] Figure 8 The fermentation condition of the comparative microbial composition 1 prepared in Comparative Example 1 after being added with red mud is shown;

[0033] Fig. 9 The survival of grass seeds and green plants planted after the comparative microbial composition 1 prepared in Comparative Example 1 was added to red mud is shown;

[0034] Fig.10 The fermentation condition of the comparative microbial composition 2 prepared in Comparative Example 2 after being added with red mud is shown;

[0035] Fig.11The survival of green plants transplanted after the comparative microbial composition 2 prepared in comparative example 2 was added to red mud is shown;

[0036] Fig.12 The fermentation condition of the comparative microbial composition 3 prepared in Comparative Example 3 after being added with red mud is shown;

[0037] Fig.13 The survival of grass seeds and green plants planted after the comparative microbial composition 4 prepared in Comparative Example 3 was added to red mud is shown. DETAILED DESCRIPTION

[0038] The technical solution of the present invention is further illustrated and described below through specific implementation modes in combination with the accompanying drawings.

[0039] In the following examples, the water used can be one or more of distilled water, water, and drinking water; unless otherwise specified, the detection methods in the following examples are conventional detection methods; the reagents in the following examples are purchased from commercial channels unless otherwise specified.

[0040] The EM bacteria used in the following examples were purchased from Beijing Xiangyun Zhongtian Technology Co., Ltd., with an effective bacterial content of ≥2×109 cfu·mL-1; molasses was purchased from Shandong Xinhechang Chemical Co., Ltd.; pure brewed rice vinegar was Hengshun pure rice vinegar; granular activated carbon was purchased from Shandong Huamo Water Treatment Equipment Co., Ltd., with an average particle size of 4 mm.

[0041] Example 1 Preparation of alkali-resistant composite microbial agent

[0042] (1) 200 L of EM bacteria, 10 kg of molasses, 1 kg of shelled eggs, 1 kg of pure brewed rice vinegar, 5 kg of red mud, 20 kg of 17-17-17 nitrogen, phosphorus and potassium compound fertilizer and 100 kg of water were mixed and then semi-closed fermentation was carried out for 72 hours. During the fermentation, stirring was performed every 12 hours for 30 minutes each time to obtain material A.

[0043] (2) Material A, 20 kg of molasses and 300 kg of water were mixed, and then semi-closed fermentation was continued for 72 hours to obtain material B.

[0044] (3) Material B, 10 kg beef peptide, 10 kg soybean peptide, 30 kg molasses and 400 kg water were mixed and fermented in a closed environment for 49 days while maintaining the system temperature no greater than 40°C. The fermentation system was then tested, and its pH was 4 and no large amount of gas was produced after shaking, indicating that material C was successfully produced.

[0045] (4) adding 0.1 wt% of granular activated carbon to material C, soaking for 30 min, then taking out the granular activated carbon adsorbed with the alkali-resistant composite microbial agent, mixing the granular activated carbon adsorbed with the alkali-resistant composite microbial agent, rice bran, potassium humate, diammonium phosphate and crushed agricultural and forestry straw, and fermenting for 72 h, white mycelium grows on the surface of the mixture and the system temperature is higher than the ambient temperature, to obtain a red mud soil composition;

[0046] Among them, the mass ratio of C material, granular activated carbon, rice bran, potassium humate, diammonium phosphate and crushed agricultural and forestry straw is 100:0.1:0.5:0.1:0.1:10.

[0047] Comparative Example 1 Preparation of Comparative Microbial Composition

[0048] (1) 200 L of EM bacteria, 10 kg of glucose, 1 kg of calcium oxide, 1 kg of acetic acid, 5 kg of red mud, 20 kg of 17-17-17 nitrogen, phosphorus and potassium compound fertilizer and 100 kg of water were mixed and then semi-closed fermentation was carried out for 72 hours. During the fermentation, stirring was performed every 12 hours for 30 minutes each time to obtain material A.

[0049] (2) Material A, 20 kg of glucose and 300 kg of water were mixed, and then semi-closed fermentation was continued for 72 hours to obtain material B.

[0050] (3) Material B, 20 kg of soybean peptide, 30 kg of glucose and 400 kg of water were mixed and fermented in a closed environment for 49 days to prepare a comparative microbial agent.

[0051] (4) adding 0.1 wt% of granular activated carbon to the comparative microbial agent, soaking for 30 min, then taking out the granular activated carbon adsorbed with the alkali-resistant composite microbial agent, mixing the granular activated carbon adsorbed with the comparative microbial agent, rice bran, potassium humate, diammonium phosphate and crushed agricultural and forestry straw, and fermenting for 72 h to obtain a comparative microbial composition 1;

[0052] Among them, the mass ratio of the comparative microbial agent, granular activated carbon, rice bran, potassium humate, diammonium phosphate and crushed agricultural and forestry straw was 100:0.1:0.5:0.1:0.1:10.

[0053] Comparative Example 2 Preparation of Comparative Microbial Composition

[0054] (1) 200 L of EM bacteria, 10 kg of molasses, 1 kg of shelled eggs, 1 kg of acetic acid, 1 kg of calcium oxide, 1 kg of aluminum oxide, 1 kg of iron oxide, 2 kg of silicon oxide, 20 kg of 17-17-17 nitrogen, phosphorus and potassium compound fertilizer and 100 kg of water were mixed and then semi-closed fermentation was carried out for 72 hours. During the fermentation, stirring was performed every 12 hours for 30 minutes each time to obtain material A.

[0055] (2) Material A, 20 kg of molasses and 300 kg of water were mixed, and then semi-closed fermentation was continued for 72 hours to obtain material B.

[0056] (3) Material B, 10 kg beef peptide, 10 kg soybean peptide, 30 kg molasses and 400 kg water were mixed and fermented in a closed environment for 49 days. The fermentation system was then tested and its pH was 4 and no large amount of gas was produced after shaking, indicating that a comparative microbial agent was prepared.

[0057] (4) adding 0.1 wt% of granular activated carbon to the comparative microbial agent and soaking for 30 min, then taking out the granular activated carbon adsorbed with the alkali-resistant composite microbial agent, mixing the granular activated carbon adsorbed with the comparative microbial agent, rice bran, potassium humate, diammonium phosphate and crushed agricultural and forestry straw, and fermenting for 72 h, white mycelium grows on the surface of the mixture and the system temperature is higher than the ambient temperature, to obtain comparative microbial composition 2;

[0058] Among them, the mass ratio of the comparative microbial agent, granular activated carbon, rice bran, potassium humate, diammonium phosphate and crushed agricultural and forestry straw was 100:0.1:0.5:0.1:0.1:10.

[0059] Comparative Example 3 Preparation of Comparative Microbial Composition

[0060] (1) 200 L of EM bacteria, 10 kg of molasses, 1 kg of shelled eggs, 1 kg of pure brewed rice vinegar, 5 kg of red mud, 20 kg of 17-17-17 nitrogen, phosphorus and potassium compound fertilizer and 100 kg of water were mixed and then semi-closed fermentation was carried out for 72 hours. During the fermentation, stirring was performed every 12 hours for 30 minutes each time to obtain material A.

[0061] (2) Material A, 20 kg of molasses and 300 kg of water were mixed, and then semi-closed fermentation was continued for 72 hours to obtain material B.

[0062] (3) Material B, 10 kg beef peptide, 10 kg soybean peptide, 30 kg molasses and 400 kg water were mixed and fermented in a closed environment for 49 days. The fermentation system was tested and its pH was 4 and no large amount of gas was produced after shaking, indicating that material C was successfully produced.

[0063] (4) Add 0.1 wt% zeolite to material C, soak for 30 min, then take out the zeolite, add rice bran, potassium humate, diammonium phosphate and crushed agricultural and forestry straw, mix well and ferment for 72 h, white mycelium grows on the surface of the mixture and the system temperature is higher than the ambient temperature, to obtain comparative microbial composition 3;

[0064] Among them, the mass ratio of alkali-resistant composite microbial agent, zeolite, rice bran, potassium humate, diammonium phosphate and crushed agricultural and forestry straw is 100:0.1:0.5:0.1:0.1:10.

[0065] Performance Testing

[0066] The red mud soil composition prepared in Example 1 and the comparative microbial compositions prepared in Comparative Examples 1-3 were mixed with red mud (pH = 14, brown in color, Figure 1 and Figure 2 ) were mixed, the amount of red mud soil composition or comparative microbial composition added was 1wt%, and grass seeds were sown or green plants were transplanted after mixed fermentation for 15 days, and the survival of the plants was continuously observed within 15 days. The results are shown in Table 1.

[0067] Table 1 Transformation effect of red mud soil composition and comparative microbial composition on red mud

[0068]

[0069]

[0070] The above description is only a preferred embodiment of the present invention, and therefore cannot be used to limit the scope of the present invention. That is, equivalent changes and modifications made according to the patent scope of the present invention and the contents of the specification should still fall within the scope of the present invention.

Claims

1. A method for preparing a red mud soil composition, characterized in that: The steps include: (1) mixing EM bacteria, part of molasses, shelled eggs, pure brewed rice vinegar, red mud, 17-17-17 nitrogen, phosphorus and potassium compound fertilizer and part of water, and then fermenting at room temperature for 70-75 hours in a semi-closed environment, during which the system temperature is controlled not to exceed 40° C., to obtain material A; (2) mixing the above-mentioned material A, part of the above-mentioned molasses and part of the water, and then fermenting at room temperature for 70-75 hours in a semi-closed environment, during which the system temperature is controlled not to exceed 40° C., to obtain material B; (3) Mixing the above-mentioned material B, beef peptide, soybean peptide, the remaining molasses and the remaining water, and fermenting at room temperature for 48-55 days in a closed environment, during which the system temperature is controlled not to exceed 40° C., to obtain material C; (4) adding granular activated carbon to the above-mentioned C material, soaking until the system temperature rises, then filtering and retaining the filter residue, and then mixing the above-mentioned filter residue, rice bran, potassium humate, diammonium phosphate and agricultural and forestry straw crushed material, and fermenting them at room temperature for 70-75 hours in a semi-closed environment to obtain a red mud soil composition; Among them, the ratio of the above-mentioned EM bacteria, molasses, shelled eggs, pure brewed rice vinegar, red mud, 17-17-17 nitrogen, phosphorus and potassium compound fertilizer, beef peptide, soybean peptide and water is 190-210L: 55-65kg: 0.8-1.2kg: 0.8-1.2kg: 4-6kg: 18-22kg: 9-11kg: 9-11kg: 780-820kg; The ratio of the amount of the molasses added in step (1), step (2) and step (3) is 0.8-1.2:1.8-2.2:2.8-3.2; the ratio of the amount of the water added in step (1), step (2) and step (3) is 0.8-1.2:2.8-3.2:3.8-4.2; the mass ratio of the filter residue, the granular activated carbon, the rice bran, the potassium humate, the diammonium phosphate and the crushed agricultural and forestry straw is 950-1050:0.8-1.2:4.8-5.2:0.8-1.2:0.8-1.2:95-105.

2. The preparation method according to claim 1, characterized in that The room temperature fermentation operation also includes: stirring for 25-40 minutes every 10-12 hours.

3. The preparation method according to claim 1 or 2, characterized in that: The ambient temperature of the room temperature fermentation is 5-40°C.

4. The preparation method according to claim 3, characterized in that: The ambient temperature of the room temperature fermentation is 26-28°C.

5. The preparation method according to claim 1, characterized in that: The soaking time in step (4) is 20-40 minutes.

6. A red mud soil composition, characterized in that: Prepared by the preparation method described in any one of claims 1 to 5.

7. A method for soilification of red mud, characterized in that: The method comprises the following steps: adding the red mud soil composition prepared by the preparation method according to any one of claims 1 to 5 into red mud, and then fermenting the composition at room temperature for 70-75 hours in a semi-closed environment.

8. The soilification method according to claim 7, characterized in that: The red mud soil composition is added in an amount of 0.1-10 wt %.

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