Electrolytic manganese residue artificial soil as well as preparation method and application thereof

Abstract

The invention provides electrolytic manganese residue artificial soil and a preparation method and application thereof, and belongs to the technical field of solid waste treatment and soil improvement. The harmless electrolytic manganese residue artificial soil is prepared from the following raw materials in parts by weight: 70-95 parts of red soil and 5-30 parts of harmless electrolytic manganese residues, the harmless electrolytic manganese residues comprise first-class harmless electrolytic manganese residues or second-class harmless electrolytic manganese residues. The artificial soil prepared by compounding the red soil and the harmless electrolytic manganese residues can be used for planting wheat, so that the soil is improved, the growth of plants can be ensured, the yield of crops is increased, the industrial solid waste of the electrolytic manganese residues is consumed to the maximum extent, and the treatment problem of the electrolytic manganese residues is solved.

Description

Technical Field

[0001] The invention relates to the technical field of solid waste treatment and soil improvement, and in particular to an electrolytic manganese slag artificial soil and a preparation method and application thereof. Background Art

[0002] As one of the important strategic resources, manganese plays a very important role in the national economic construction. It is widely used in metallurgy, chemical industry and other industries. Manganese can be used as an alloying element, desulfurizer and deoxidizer in steelmaking, so about 90% of manganese is consumed in the steel industry. In addition, about 10% of manganese is also used to prepare various manganese salts for use in batteries, printing paint, electronics, building materials and other industries. The electrolytic manganese slag accumulated due to historical and technical problems may have exceeded 100 million tons, and is increasing by 10 million tons each year. With the further improvement of the productivity of the electrolytic manganese industry, the increasing mining of manganese ore has exhausted high-grade manganese ore, and the use of low-grade manganese ore raw materials for production will produce 10 to 15 tons of electrolytic manganese slag for every ton of metallic manganese produced, further increasing the pressure on environmental protection.

[0003] In order to completely solve the environmental risks brought by the storage of electrolytic manganese slag, the "production based on slag" policy is implemented for electrolytic manganese slag enterprises, so that the consumption of electrolytic manganese slag by enterprises is linked to the production of products such as metallic manganese, forcing enterprises to continuously improve the comprehensive utilization rate of electrolytic manganese slag and promote the green, innovative, intensive and efficient development of the industry. However, the current resource-based comprehensive utilization methods of electrolytic manganese slag are not mature, and large-scale promotion and application are rare. The new round of environmental protection policies have put forward higher requirements for the comprehensive management of electrolytic manganese slag, and the increase in environmental protection investment has significantly increased production costs. Therefore, it is imperative to carry out the comprehensive utilization of electrolytic manganese slag, and it is urgent to carry out research on the reduction, harmlessness and resource utilization technology of electrolytic manganese slag.

[0004] Rapid urbanization and the exploitation of fossil energy also occupy or seal a large amount of surface soil resources. Mining is currently the largest human activity that changes land use and damages terrestrial ecosystems. Mining occupies and damages about 54 million mu of land in China. Among them, the mines currently under development occupy and damage about 20 million mu of land, and the historical mines occupy and damage about 34 million mu of land. Due to the increasing scarcity of soil resources, the simple method of ecological restoration using a large amount of imported soil is restricted, so the research direction of making an artificial soil that can reduce the use of or completely replace the use of imported soil has attracted much attention. The main way to make artificial soil is to improve natural soil into artificial soil with better performance through certain treatment or to use several materials to mix and prepare artificial soil without natural soil. Artificial soil, also known as topsoil substitute material, artificial soil, new soil source, and technologically new soil, is a new type of soil resource recognized by the Food and Agriculture Organization of the United Nations. Therefore, it is of great significance to study a harmless electrolytic manganese artificial soil and its preparation method for planting wheat. Summary of the invention

[0005] The object of the present invention is to provide a harmless electrolytic manganese artificial soil, its preparation method and application, so as to solve the problem that electrolytic manganese slag cannot be treated on a large scale in the prior art.

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

[0007] The present invention provides a harmless electrolytic manganese slag artificial soil, which is made of the following raw materials in parts by weight: 70-95 parts of red soil, 5-30 parts of harmless electrolytic manganese slag; the harmless electrolytic manganese slag includes Class I harmless electrolytic manganese slag or Class II harmless electrolytic manganese slag.

[0008] Preferably, the preparation method of the Class II harmless electrolytic manganese slag is: washing the electrolytic manganese slag, adding quicklime and sodium silicate, and then carrying out a solidification reaction to obtain the Class II harmless electrolytic manganese slag.

[0009] Preferably, the specific steps of the washing are: washing the electrolytic manganese slag with the anolyte generated during the electrolytic manganese process.

[0010] Preferably, the addition amount of the quicklime accounts for 3-5% of the mass of the electrolytic manganese slag; the addition amount of the sodium silicate accounts for 1-3% of the mass of the electrolytic manganese slag.

[0011] Preferably, the time of the solidification reaction is 44-52 h.

[0012] Preferably, the preparation method of the Class I harmless electrolytic manganese slag is: performing secondary solidification on the Class II harmless electrolytic manganese slag to obtain the Class I harmless electrolytic manganese slag.

[0013] Preferably, quartz sand is used as an additive during the secondary solidification, and the mass ratio of the Class II harmless electrolytic manganese slag to the quartz sand is 1:2-4.

[0014] The present invention also provides a preparation method of the above-mentioned harmless electrolytic manganese slag artificial soil, weighing the red soil and the harmless electrolytic manganese slag according to parts by weight, mixing them and passing them through a sieve to obtain the harmless electrolytic manganese slag artificial soil.

[0015] The present invention also provides an application of the above-mentioned harmless electrolytic manganese slag artificial soil in growing wheat.

[0016] Preferably, after soaking wheat seeds in a potassium permanganate solution, rinsing them, and finally sowing them in the harmless electrolytic manganese slag artificial soil.

[0017] The beneficial effects of the present invention:

[0018] (1) The present invention prepares artificial soil from harmless electrolytic manganese residue, which can maximize the consumption of industrial solid waste of electrolytic manganese residue and solve the problem of treating electrolytic manganese residue.

[0019] (2) The present invention also provides a soil improvement scheme, which reduces the dependence on traditional fertilizers and modifiers and can reduce agricultural production costs.

[0020] (3) The artificial soil prepared by mixing red soil and harmless electrolytic manganese residue in the present invention can be used to grow wheat. It not only improves the soil but also ensures plant growth, increases crop yields, safeguards food security and promotes the sustainable development of agriculture. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 shows the growth of potted wheat for 3 days;

[0022] Figure 2 shows the growth of potted wheat for 6 days;

[0023] Figure 3 is a graph showing the relationship between the wheat germination rate and the artificial soil formula, where the blank corresponds to pretreated red soil, fresh manganese residue corresponds to electrolytic manganese residue artificial soil without harmless treatment, type II manganese residue corresponds to type II harmless electrolytic manganese residue artificial soil, type I manganese residue corresponds to type I harmless electrolytic manganese residue artificial soil, and 0.05, 0.1, and 0.3 correspond to the content of manganese residue in each group of artificial soil. Figures 4 to 7 The corresponding relationship in Figure 3 ;

[0024] Figure 4 is a graph showing the relationship between the pH value and the formula of harmless manganese residue artificial soil, electrolytic manganese residue artificial soil without harmless treatment, and pretreated red soil;

[0025] Figure 5 is a graph showing the relationship between the conductivity and the formula of harmless manganese residue artificial soil, electrolytic manganese residue artificial soil without harmless treatment, and pretreated red soil;

[0026] Figure 6 is a graph showing the relationship between the organic matter and the formula of harmless manganese residue artificial soil, electrolytic manganese residue artificial soil without harmless treatment, and pretreated red soil;

[0027] Figure 7 is a graph showing the relationship between the bulk density and the formula of harmless manganese residue artificial soil, electrolytic manganese residue artificial soil without harmless treatment, and pretreated red soil. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0028] The present invention provides a harmless electrolytic manganese residue artificial soil, which is made from the following raw materials in parts by weight: 70-95 parts of red soil and 5-30 parts of harmless electrolytic manganese residue; the harmless electrolytic manganese residue includes Class I harmless electrolytic manganese residue or Class II harmless electrolytic manganese residue.

[0029] In the present invention, the preparation method of the Class II harmless electrolytic manganese residue is: washing the electrolytic manganese residue, adding quicklime and sodium silicate, and then carrying out a solidification reaction to obtain the Class II harmless electrolytic manganese residue.

[0030] In the present invention, the specific steps of the washing are: washing the electrolytic manganese residue with the anolyte generated during the electrolytic manganese process.

[0031] In the present invention, the addition amount of the quicklime accounts for 3-5% of the mass of the electrolytic manganese residue, preferably 4%; the addition amount of the sodium silicate accounts for 1-3% of the mass of the electrolytic manganese residue, preferably 2%.

[0032] In the present invention, the time of the solidification reaction is 44-52 h, preferably 46-50 h, and further preferably 48 h.

[0033] In the present invention, the Class II harmless electrolytic manganese residue meets the requirements of Class II general industrial solid waste in the "Pollution Control Standard for Storage and Landfill of General Industrial Solid Wastes".

[0034] In the present invention, the preparation method of the Class I harmless electrolytic manganese residue is: performing secondary solidification on the Class II harmless electrolytic manganese residue to obtain the Class I harmless electrolytic manganese residue.

[0035] In the present invention, quartz sand is used as an additive during the secondary solidification, and the mass ratio of the Class II harmless electrolytic manganese residue to quartz sand is 1:2-4, preferably 1:3.

[0036] In the present invention, the Class I harmless electrolytic manganese residue meets the requirements of Class I general industrial solid waste in the "Pollution Control Standard for Storage and Landfill of General Industrial Solid Wastes".

[0037] The present invention also provides a preparation method of the above-mentioned harmless electrolytic manganese residue artificial soil, weighing red soil and harmless electrolytic manganese residue according to parts by weight, mixing them, and passing them through a sieve to obtain the harmless electrolytic manganese residue artificial soil.

[0038] In the present invention, the red soil is preferably pretreated before being mixed with the harmless electrolytic manganese residue, and the purpose is to remove large stone particles and plant rhizomes.

[0039] The present invention also provides an application of the above-mentioned harmless electrolytic manganese residue artificial soil in growing wheat.

[0040] In the present invention, wheat seeds are soaked in a potassium permanganate solution, rinsed, and finally sown in a harmless electrolytic manganese residue artificial soil.

[0041] In the present invention, the mass concentration of the potassium permanganate solution is 1‰, and the soaking time is 20 - 40 min, preferably 30 min.

[0042] In the present invention, the rinsing method is to rinse once with tap water and three times with distilled water.

[0043] The technical solutions provided by the present invention will be described in detail below in conjunction with embodiments, but they should not be construed as limiting the protection scope of the present invention.

[0044] The untreated electrolytic manganese residue used in the examples and comparative examples of the present invention comes from Guangxi region, and its main elemental composition is: O 44.7221%, Si 13.2529%, Ca 13.1057%, S 11.2400%, Fe 8.4863%, Mn 5.5698%, Al 1.3019%, Mg 0.9866%, K 0.4786%, Ba 0.3044%, Ti 0.197%, P 0.1243%, Na 0.0621%, Cl 0.0371%, Ni 0.0313%, Sr 0.0301%, V 0.0216%, Cu 0.016%, Pb 0.0133%; the red soil comes from Guangxi region.

[0045] Example 1

[0046] The untreated electrolytic manganese residue is washed with anolyte (the anolyte is generated during the electrolysis of manganese), then 4% quicklime and 2% sodium silicate are added, and stirred and mixed for 48 h for a solidification reaction to obtain the second - type harmless electrolytic manganese residue, meeting the requirements of the second - type general industrial solid waste in the "Pollution Control Standard for Storage and Landfill of General Industrial Solid Wastes".

[0047] The second - type harmless electrolytic manganese residue is naturally air - dried, screened through a 5 - mm aperture sieve for standby. The red soil is pretreated to remove large stone particles and plant rhizomes to obtain pretreated red soil. The second - type harmless electrolytic manganese residue and the pretreated red soil are mixed, and fully mixed through a sieve to obtain the second - type harmless electrolytic manganese residue artificial soil, numbered 5, 6, 7. Among them, in No. 5, there are 5 parts of the second - type harmless electrolytic manganese residue and 95 parts of pretreated red soil; in No. 6, there are 10 parts of the second - type harmless electrolytic manganese residue and 90 parts of pretreated red soil; in No. 7, there are 30 parts of the second - type harmless electrolytic manganese residue and 70 parts of pretreated red soil. The total mass of each group of the second - type harmless electrolytic manganese residue artificial soil is 400 g.

[0048] Example 2

[0049] The Class II harmless electrolytic manganese slag and quartz sand in Example 1 are mixed in a mass ratio of 1:3 and subjected to secondary solidification to obtain Class I harmless electrolytic manganese slag, which meets the requirements of Class I general industrial solid waste in the "General Industrial Solid Waste Storage and Landfill Pollution Control Standards".

[0050] The first type of harmless electrolytic manganese slag is naturally air-dried, passed through a 5mm aperture sieve for later use, and the red soil is pretreated to remove large stone particles and plant roots to obtain pretreated red soil. The first type of harmless electrolytic manganese slag and the pretreated red soil are mixed, and after being fully mixed through a sieve, the first type of harmless electrolytic manganese slag artificial soil is obtained, which is numbered 8, 9, and 10, wherein the first type of harmless electrolytic manganese slag in number 8 is 5 parts, and the pretreated red soil is 95 parts, the first type of harmless electrolytic manganese slag in number 9 is 10 parts, and the pretreated red soil is 90 parts, and the first type of harmless electrolytic manganese slag in number 10 is 30 parts, and the pretreated red soil is 70 parts, and the total mass of each group of the first type of harmless electrolytic manganese slag artificial soil is 400g.

[0051] Comparative Example 1

[0052] The electrolytic manganese slag without harmless treatment is naturally air-dried, passed through a 5mm aperture sieve for standby use, and the red soil is pretreated to remove large stone particles and plant roots to obtain pretreated red soil. The electrolytic manganese slag without harmless treatment and the pretreated red soil are mixed, and after being fully mixed through a sieve, an electrolytic manganese slag artificial soil without harmless treatment is obtained, which is numbered 2, 3, and 4, wherein 5 parts of electrolytic manganese slag without harmless treatment and 95 parts of pretreated red soil in number 2, 10 parts of electrolytic manganese slag without harmless treatment and 90 parts of pretreated red soil in number 3, 30 parts of electrolytic manganese slag without harmless treatment and 70 parts of pretreated red soil in number 4, and the total mass of each group of electrolytic manganese slag artificial soil without harmless treatment is 400g.

[0053] Comparative Example 2

[0054] The red soil was pretreated to remove large stone particles and plant roots to obtain pretreated red soil. 400 g of the pretreated red soil was directly taken as a blank control group, numbered 1.

[0055] Application Examples

[0056] The type II harmless electrolytic manganese slag artificial soil of Example 1, the type I harmless electrolytic manganese slag artificial soil of Example 2, the unharmless electrolytic manganese slag artificial soil of Comparative Example 1, and the pretreated red soil of Comparative Example 2 were placed in flower pots and numbered accordingly.

[0057] The wheat seeds were soaked in a potassium permanganate solution with a mass concentration of 1‰ for 30 min for disinfection and standby. 50 wheat seeds with large and plump grains and consistent maturity were selected, rinsed once with tap water and then three times with distilled water, and then sown in the above flower pots filled with artificial soil and pretreated red soil, 5 seeds were sown in each flower pot. After sowing, water was regularly added to keep the potted plants moist. During the experiment, the germination of wheat was regularly observed and relevant records were made. After growing for 6 days, the seed germination rate was calculated. The experimental results are shown in Figures 1 to 3 。

[0058] From Figure 2 and Figure 3 it can be seen that the artificial soil made of electrolytic manganese residue without harmless treatment contains high concentrations of heavy metals. When the addition amount is 30%, the germination rate is only 12%. This shows that the electrolytic manganese residue without harmless treatment has a toxic effect on the growth and development of plants. Considering factors such as the consumption of electrolytic manganese residue and the soil planting capacity, the electrolytic manganese residue without harmless treatment is not used as the raw material for artificial soil. When the addition amount of the second type of harmless electrolytic manganese residue and the first type of harmless electrolytic manganese residue is 30%, the wheat germination rate reaches 60% and above, which is the same as that of the pretreated red soil (blank control group), indicating good planting effects.

[0059] After growing for 6 days, artificial soil was taken from each flower pot, and pretreated red soil was taken from the blank control group. After pretreatment according to Part 8 of HJ / T166-2004 "Technical Specifications for Soil Environmental Monitoring", the physical and chemical properties of the soil were analyzed and measured. The analysis indicators included pH value, conductivity, organic matter content, and soil bulk density. The test methods are as follows:

[0060] The determination method of pH value refers to HJ 962-2018 "Determination of Soil pH Value - Potentiometry". The acid-base reaction of the soil is an important property of the soil and also its basic chemical property. On the one hand, it can reflect other chemical properties of the soil, especially the base composition status, and on the other hand, it restricts many physical, chemical, and biological processes and properties in the soil. The growth of plants has a certain suitable pH value range, and most plants are suitable for growing at a pH value of 6.5 - 9.0. The test results are shown in Table 1:

[0061] Table 1 Test Results of pH Value

[0062] Number 1 2 3 4 5 6 7 8 9 10 pH value 7.4 6.68 6.64 6.9 7.28 7.46 7.44 7.16 7.15 7.41

[0063] It can be seen from Table 1 that the electrolytic manganese residue without harmless treatment is acidic, and the average pH is 6.74 after addition. The artificial soil is weakly acidic, and the artificial soil prepared by adding the second type of harmless electrolytic manganese residue and the first type of harmless electrolytic manganese residue is weakly alkaline. This shows that using the second type of harmless electrolytic manganese residue and the first type of harmless electrolytic manganese residue can effectively improve the problem of soil acidity, making it suitable for plant growth.

[0064] The method for measuring conductivity refers to HJ 802-2016 "Determination of Soil Conductivity - Electrode Method". Soil conductivity is an indicator for measuring soil water-soluble salts, and soil water-soluble salts are an important indicator of the mineral nutrients that can be rapidly utilized by plants in the surface soil, and are factors for judging whether the salt ions in the soil limit crop growth. If the soil EC value is too high or too low, it will hinder the growth of crops. Different plants have different suitable soil EC values according to their fertilizer requirements and growth stages, generally between 0.4 and 2.0 ms / cm. The measurement results are shown in Table 2:

[0065] Table 2 Conductivity Test Results

[0066]

[0067] It can be seen from Table 2 that the conductivity of the blank control group is 0.07 mS / cm. Due to the addition of electrolytic manganese slag, the conductivity of the artificial soil has increased significantly, which is because the manganese slag contains a large amount of sulfates. However, it should not exceed 2.5 mS / cm at most. From the data, both the second type of harmless electrolytic manganese slag and the first type of harmless electrolytic manganese slag meet this condition.

[0068] The method for measuring the organic matter content is the potassium dichromate - sulfuric acid digestion method (GB9834-88). Under the condition of external heating at 180 °C, keep boiling for 5 min, then use 20 mL of potassium dichromate - sulfuric acid solution with a concentration of 0.4 mol / L and 3 mL of concentrated sulfuric acid solution to oxidize the organic carbon in the soil, add 3 - 5 drops of o-phenanthroline as an indicator, and titrate the remaining potassium dichromate with a 56 g / L ferrous sulfate solution. Through the amount of potassium dichromate consumed, the content of organic carbon in the soil can be calculated, and multiplying by the corresponding coefficient is the organic matter content. Soil organic matter content refers to all carbon-containing organic compounds in the soil. The test results are shown in Table 3:

[0069] Table 3 Organic Matter Content Test Results

[0070]

[0071] It can be seen from Table 3 that the organic matter content of the blank control group is 3.39 mg / L. After adding three different types of electrolytic manganese slag, the organic matter content of the artificial soil has decreased by a similar extent, which is inevitable. Consider designing to add organic soil improvers during subsequent formulation optimization to reduce the impact of manganese slag addition on soil organic matter.

[0072] The method for measuring the bulk density is: the core cutter method. Use a 100 cm 3 core cutter to take the undisturbed soil of the measured potted plant, and measure the mass of the soil after drying as m 1 , and the calculation formula is ρb = m 1 / 100. Soil bulk density refers to the weight of an object per unit volume and is one of the indicators of soil maturity. For soils with a higher degree of maturity, the volumetric specific gravity is usually smaller. The test results are shown in Table 4:

[0073] Table 4 Test Results of Bulk Density

[0074]

[0075] As can be seen from Table 4, the bulk density of the blank control group is 1.13 g / cm 3 , and adding three different types of manganese slag, even with an addition amount of 30%, only has a weak impact on soil bulk density. Therefore, the addition of manganese slag has no significant effect on this physical and chemical property of soil bulk density and does not interfere with the growth of plants.

[0076] The method for determining the leaching concentration of heavy metals refers to HJ 557-2010 "Solid Waste Leaching Toxicity Leaching Method - Horizontal Oscillation Method". Heavy metals in soil can have a certain toxic effect on plants, causing a series of physiological changes, such as plant height, primary root length, and leaf area. At the same time, heavy metals can enter the human body through the food chain and cause harm to the human body due to cumulative effects. The test results are shown in Table 5:

[0077] Table 5 Test Results of Heavy Metal Leaching Concentration

[0078]

[0079]

[0080] As can be seen from Table 5, for the artificial soil prepared from electrolytic manganese slag without harmless treatment, the leaching concentration of Mn 2+ is very high, while for the artificial soil prepared from the second type of harmless electrolytic manganese slag and the first type of harmless electrolytic manganese slag, the leaching concentration of Mn 2+ is relatively low, both lower than the first-class standard of the maximum allowable discharge concentration in the "Integrated Wastewater Discharge Standard" - 2.0 mg / L. Manganese slag itself contains trace amounts of Fe elements and does not affect plant growth. The leaching concentrations of other heavy metals all meet the first-class standard of the maximum allowable discharge concentration in the "Integrated Wastewater Discharge Standard". Therefore, the addition of harmless electrolytic manganese slag does not cause the heavy metal ion concentration in the artificial soil to exceed the standard and meets the corresponding standard requirements.

[0081] The above are only the preferred embodiments of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the principle of the present invention, several improvements and refinements can be made, and these improvements and refinements should also be regarded as the protection scope of the present invention.

Claims

1. A harmless electrolytic manganese slag artificial soil, characterized in that: The harmless electrolytic manganese slag artificial soil is made of the following raw materials in parts by weight: 70-95 parts of red soil and 5-30 parts of harmless electrolytic manganese slag; the harmless electrolytic manganese slag includes Class I harmless electrolytic manganese slag or Class II harmless electrolytic manganese slag.

2. The harmless electrolytic manganese slag artificial soil according to claim 1, characterized in that: The preparation method of the type II harmless electrolytic manganese slag is: washing the electrolytic manganese slag, adding quicklime and sodium silicate, and then performing a solidification reaction to obtain the type II harmless electrolytic manganese slag.

3. The harmless electrolytic manganese slag artificial soil according to claim 2, characterized in that: The specific steps of washing are: washing the electrolytic manganese slag with the anolyte generated in the electrolytic manganese process.

4. The harmless electrolytic manganese slag artificial soil according to claim 2 or 3, characterized in that: The added amount of quicklime accounts for 3-5% of the mass of electrolytic manganese slag; the added amount of sodium silicate accounts for 1-3% of the mass of electrolytic manganese slag.

5. The harmless electrolytic manganese slag artificial soil according to claim 4, characterized in that: The curing reaction time is 44 to 52 hours.

6. The harmless electrolytic manganese slag artificial soil according to claim 2, 3 or 5, characterized in that: The preparation method of the Class I harmless electrolytic manganese slag is: secondary solidification of the Class II harmless electrolytic manganese slag to obtain the Class I harmless electrolytic manganese slag.

7. The harmless electrolytic manganese slag artificial soil according to claim 6, characterized in that: During the secondary solidification, quartz sand is used as an additive, wherein the mass ratio of the type II harmless electrolytic manganese slag to the quartz sand is 1:2-4.

8. The method for preparing harmless electrolytic manganese slag artificial soil according to any one of claims 1 to 7, characterized in that: Red soil and harmless electrolytic manganese slag are weighed according to weight, mixed and sieved to obtain harmless electrolytic manganese slag artificial soil.

9. Use of the harmless electrolytic manganese slag artificial soil according to any one of claims 1 to 7 in planting wheat.

10. The use of harmless electrolytic manganese slag artificial soil in wheat planting according to claim 9, characterized in that: Soak the wheat seeds in potassium permanganate solution, rinse them, and finally sow them in harmless electrolytic manganese slag artificial soil.

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