A multifunctional soil conditioner for fine-grained copper tailings and preparation method thereof

Abstract

This application relates to a multifunctional soil conditioner for fine-grained copper tailings and its preparation method, belonging to the field of mining engineering technology. The raw materials for this multifunctional soil conditioner for fine-grained copper tailings include: 10-15 parts fine-grained copper tailings, 8-12 parts calcium-based activator, 1-3 parts potassium-based activator, 2-5 parts sodium-based activator, 0.8-1.2 parts organic activator, and 35-50 parts deionized water. The steps include: drying the copper tailings, crushing and weighing, preparing the basic mix, grinding and aging, high-temperature roasting, and grinding and sieving or extrusion granulation. The resulting multifunctional soil conditioner (silicon fertilizer) product has an effective SiO2 content as high as 38.5%, and its performance indicators meet the requirements of "NY / T797-2004 Silicon Fertilizer". It can be used for the remediation of acidic soils, saline-alkali soils, etc., improving the soil's structural function, nutrient function, and environmental function, meeting the needs of high-standard farmland, saline-alkali land transformation, and acidic soil treatment.

Description

Technical Field

[0001] The present application relates to a multifunctional soil conditioner for fine-grained copper tailings and a preparation method thereof, and belongs to the technical field of mining engineering. Background Art

[0002] At present, the stockpile of tailings in my country exceeds 20 billion tons, and the comprehensive utilization rate is only 18.9%. Among them, underground filling in mines is one of the important ways of comprehensive tailings disposal, accounting for 53% of the total tailings utilization, while the utilization rate of tailings abroad can reach more than 60%, which is a big gap. Under the severe environmental protection policy situation, many domestic mines have invested in the exploration of tailings resource utilization. In addition to using tailings for underground cementation filling in mines, some directly cover the tailings piles with soil to create fields, plant crops or plant trees, but these utilization methods are relatively rough and low in added value, and it is difficult to effectively solve the problem of large-scale disposal of tailings. Therefore, it is urgent to develop economically feasible copper tailings resource utilization technology and establish relevant standards and specifications to break through the technical barriers to large-scale value-added disposal of copper tailings.

[0003] At present, the research progress on the resource utilization of copper tailings mainly focuses on the utilization of building materials, such as using tailings as raw materials for cement, tiles, aerated concrete, refractory materials, glass, ceramsite, concrete aggregate, etc., or producing tailings sand by grading and quality classification to replace part of the machine-made sand for the production of concrete, construction of roads, pavement materials, etc. The existing research mainly has the following problems: First, the existing technical solutions are mostly to use tailings to produce some conventional building materials products, the products are single, and the product functionality is insufficient, resulting in low product added value, and it is difficult to overcome the problems of transportation distance and cost; second, there is a lack of systematic mineralogy and physical and chemical properties research on its own tailings, and it only stays at the extensive incorporation utilization, and the working principle of the process is unclear; third, the environmental impact assessment of tailings building materials products is lacking, resulting in restrictions in the downstream market application process; fourth, there is insufficient understanding of the beneficial and harmful components in the tailings, and there is a lack of effective tailings pretreatment technology, which indirectly leads to poor performance of the final product and lack of competitiveness.

[0004] Soil conditioner (silicon fertilizer) is the fourth largest element fertilizer after nitrogen, phosphorus and potassium. It can help increase crop yields and incomes, enhance crop resistance to lodging, and can also be used for high-standard farmland construction, saline-alkali land improvement and soil restoration. According to statistics, my country's paddy soil lacks more than 50% of silicon, and "high yield but not high quality, high quality but not high yield" has always plagued domestic crop planting.

[0005] From the chemical composition of copper tailings sand, we can know that the main chemical components are SiO2, Al2O3, CaO, Fe2O3 and K2O, as well as a small amount of MgO, etc., and the SO3 content is relatively low. The chemical composition of tailings is similar to that of natural soil, with only differences in the content of components. The content of SiO2 and K2O components is very high, and its silicon dioxide content is high. It also contains potassium, calcium, magnesium, iron and other elements required for plant growth. Therefore, it is a feasible way to utilize copper tailings resources by disposing tailings to meet the technical requirements of soil conditioner (silicon fertilizer) products.

[0006] There are precedents for synthesizing soil conditioners from mineral resources in the prior art. Patent CN111116241A discloses a method for preparing fully water-soluble silicon fertilizer from silicon ore, which uses silicon ore to be graded and crushed to (40 mesh-1500 mesh) to make silicon ore powder, which is fully mixed with alkaline compounds such as sodium hydroxide, potassium hydroxide, sodium carbonate, etc., and placed in a thermal reactor such as a tunnel kiln, a kiln, a crucible, etc. for reaction. After the reaction is completed, it is dissolved in water, and after solid-liquid separation, the obtained liquid product is liquid water-soluble silicon fertilizer, and its water-soluble SiO2 ≥ 20%; the liquid can also be dried to form a solid powder, which is solid water-soluble silicon fertilizer; the residue after solid-liquid separation is dried to form an active silicon fertilizer and meets the requirements of NY / T797-2004, that is, soluble SiO2 ≥ 20%. It has the outstanding characteristics of high silicon conversion rate in raw materials, cascade utilization of silicon ore, no three wastes, green environmental protection, and low production cost, realizing the circular economy and energy conservation and emission reduction in the production process, and is a new process technology for efficient and green utilization of silicon ore. Patent CN107876216A discloses a method for recovering molybdenum and sulfur from molybdenum tailings and using them as raw materials to prepare molybdenum silicon fertilizer, wherein molybdenum concentrate and sulfur concentrate are recovered by flotation, heavy metal ions in the tailings are removed by flotation again, and then the tailings from which heavy metal ions have been removed are mixed with dolomite, and silicon fertilizer raw materials are prepared according to the proportions of the components in the silicon fertilizer raw material table, and the finished silicon fertilizer is obtained after calcination and water quenching. This reduces the discharge of tailings from the source, and has far-reaching significance for improving the comprehensive utilization rate of my country's mineral resources, reducing emissions, and promoting agricultural development.

[0007] So far, there is no existing technology for preparing soil conditioners using copper tailings, and the effective silicon content in the silicon fertilizer products finally obtained by the above technology still needs to be improved.

[0008] Technical content

[0009] In order to solve the above technical problems, a technical idea of ​​using copper tailings to prepare soil conditioner (silicon fertilizer) products is proposed. The core of preparing soil conditioner (silicon fertilizer) products from copper tailings is to meet the technical requirements of soil conditioner (silicon fertilizer) products after the tailings are disposed. The production of tailings-based soil conditioner (silicon fertilizer) products is usually carried out in three ways: simple grinding, hydrothermal reaction and high-temperature calcination. High-temperature calcination is the most common and commonly used method for preparing soil conditioner (silicon fertilizer). The prepared soil conditioner (silicon fertilizer) products can provide nutritional functions, environmental functions and structural functions.

[0010] This application obtained the optimal mix ratio through roasting activation test and granulation test of fine-grained copper tailings. The effective SiO2 content of the produced soil conditioner (silicon fertilizer) product is as high as 38.5%. The performance indicators meet the requirement of effective SiO2 content ≥ 20% stipulated in the "NY / T797-2004 Silicon Fertilizer" standard, which fully proves the feasibility of the technical route.

[0011] The first technical solution provided by the present application is a multifunctional soil conditioner for fine-grained copper tailings, whose raw materials include: 10-15 parts of fine-grained copper tailings, 8-12 parts of calcium-based activators, 1-3 parts of potassium-based activators, 2-5 parts of sodium-based activators, 0.8-1.2 parts of organic activators, and 35-50 parts of deionized water.

[0012] Furthermore, the particle size of the fine-grained copper tailings is above 200 meshes, and the SiO2 content is 55-80%. By selecting copper tailings of this fineness, it is more conducive to obtaining the fineness required for the soil conditioner in the subsequent grinding and dispersion process. By selecting copper tailings in the above SiO2 content range, a soil conditioner with a higher effective silicon content can be obtained, but if the SiO2 content is higher than 80%, it will not be well activated, resulting in a decrease in the final effective silicon content.

[0013] Furthermore, the calcium-based activator is one or more of calcium oxide, calcium hydroxide, and calcium carbonate, preferably calcium oxide. On the one hand, the calcium-based activator can provide calcium elements necessary for plant growth, and under certain conditions, it can react with SiO2 in copper tailings to obtain calcium silicate, which is a kind of silicon fertilizer and calcium fertilizer, and at the same time increases the effective amount of silicon in the product. On the other hand, the calcium-based activator can chemically react with atoms or ions on the surface active sites of minerals, thereby changing the surface physical and chemical properties of the minerals, thereby obtaining a soil conditioner that is beneficial to plant nutrient absorption.

[0014] Further, the potassium activator is one or more of potassium hydroxide, potassium hydrogen phosphate, potassium carbonate, and potassium acetate, preferably potassium hydroxide. On the one hand, the potassium activator can provide potassium elements necessary for plant growth, which can react with SiO2 in the copper tailings under certain conditions to obtain potassium silicate, which belongs to a kind of silicon fertilizer and potash fertilizer, and at the same time increases the effective amount of silicon in the product. On the other hand, the above-mentioned potassium activator can provide an alkaline environment required for activation, which can promote the conversion of SiO2 in the tailings into silicate, thereby increasing the effective amount of silicon in the product.

[0015] Further, the sodium activator is one or more of sodium hydroxide, sodium hydrogen phosphate, and sodium carbonate, preferably sodium hydroxide. On the one hand, the sodium activator can provide the sodium element necessary for plant growth, and under certain conditions, it can react with SiO2 in the copper tailings to obtain sodium silicate, which belongs to a kind of silicon fertilizer and sodium fertilizer, and at the same time increases the effective amount of silicon in the product. On the other hand, the above-mentioned sodium activator can provide the alkaline environment required for activation, which can promote the conversion of SiO2 in the tailings into silicate, thereby increasing the effective amount of silicon in the product.

[0016] Furthermore, the organic activator is one or both of ethylenediamine phosphate and humic acid, preferably ethylenediamine phosphate. The organic activator can selectively bond and adsorb with active calcium, magnesium and iron on the surface of the mineral to improve its activation performance, thereby obtaining active calcium, magnesium, iron, phosphorus and the like, and at the same time increasing the content of active silicon. Ethylenediamine phosphate has a good activation effect on both bound copper oxide and free copper oxide in copper tailings.

[0017] Furthermore, the second technical solution provided by the present application is a method for preparing a multifunctional soil conditioner for fine-grained copper tailings, the steps of which include:

[0018] (1) Drying of copper tailings. Take the fine-grained copper tailings and place them in a drying furnace for drying.

[0019] (2) Crushing and weighing. Take the dried fine-grained copper tailings, crush them and weigh them accurately for later use.

[0020] (3) Preparation of basic batch materials: Weigh the calcium-based activator, potassium-based activator, organic activator and deionized water according to the amount and set aside.

[0021] (4) Grinding and aging. Take the above-mentioned fine-grained copper tailings, calcium activator, potassium activator, sodium activator and organic activator, mix and grind, add deionized water and continue to stir and disperse, and age after uniform dispersion to obtain a mixture. (5) High-temperature roasting. The mixture is roasted at high temperature, the roasting temperature is controlled to be 800-1000℃, the roasting time is 10-90min, and cooled.

[0022] (6) Grinding and sieving. Grind the cooled mixture and then sieve it to obtain the multifunctional soil conditioner; or

[0023] Extrusion granulation: taking the cooled mixture, extruding granulation and then screening to obtain the multifunctional soil conditioner.

[0024] Furthermore, in the above step (1), the drying temperature is 150-200° C., and the drying time is 20-40 min.

[0025] Furthermore, the fineness after crushing in the above step (2) is above 200 mesh.

[0026] Furthermore, the grinding fineness in the above step (4) is above 400 mesh, and the aging time is 18-24 hours.

[0027] Furthermore, in the above step (5), the calcination temperature is 900° C. and the calcination time is 50 min.

[0028] Furthermore, in the above step (6), the fineness of the powder after grinding and screening is ≤250 μm.

[0029] Through the above preparation process, grinding is first used to fully mix the materials, and the surface of the materials is broken during the grinding process, so that the contact surface of the mineral with the activator is increased and the fresh surface is exposed. The aging process is conducive to the full change of the surface properties of the material particles, which is conducive to the activation in the subsequent high-temperature roasting process. High-temperature roasting can promote the activation reaction of the activator with the copper tailings at high temperature and promote the formation of silicon fertilizer. The powder-like multifunctional soil conditioner can be obtained by grinding and screening, and the granular multifunctional soil conditioner can be obtained by the extrusion granulation process, which can be selected according to actual needs.

[0030] Beneficial Effects

[0031] (1) This application uses the above-mentioned raw material formula and preparation process to treat the tailings through mechanical and chemical composite excitation methods during the basic batch preparation and high-temperature roasting process, so that the inert components therein are converted into effective active components that are beneficial to plant absorption, and finally produce a multifunctional soil conditioner product. By accurately controlling the raw material ratio and controlling the roasting temperature and time, the maximum utilization of the effective components in the copper tailings is achieved.

[0032] (2) In this application, calcium-based activators, potassium-based activators, sodium-based activators and organic activators are comprehensively used to fully utilize calcium, potassium and sodium as fertilizer elements, and fully activate the inert substances in the copper tailings to transform them into active components that can be absorbed by plants. Through organic-inorganic combined activation, the activation efficiency of multivalent metal cations and anions on minerals can be fully utilized. Under alkaline conditions, multivalent metal cations can bind to the mineral surface—O -On the one hand, it aggregates by ionic bonds, and on the other hand, it reacts with the acid radical of the collector to form insoluble salts, thereby increasing the degree of bonding and adsorption of the activator on the mineral, making the mineral fully activated.

[0033] (3) The multifunctional soil conditioner (silicon fertilizer) product obtained in this application has an effective SiO2 content of up to 38.5%, and its performance indicators meet the requirements of "NY / T797-2004 Silicon Fertilizer". It can be used for the restoration of acidic soil, saline-alkali soil and other lands, improve the structural function, nutrient function and environmental function of the soil, and meet the needs of high-standard farmland, saline-alkali land transformation and acidic soil management.

[0034] (4) This application can achieve high-value utilization of copper tailings, significantly increase the added value of comprehensive utilization products, and form a new economic growth point. DETAILED DESCRIPTION

[0035] The following non-limiting embodiments may enable those skilled in the art to more fully understand the present invention, but do not limit the present invention in any way.

[0036] The following fine-grained copper tailings are selected from the Chengmenshan copper mine tailings in Jiujiang City, Jiangxi Province. The main chemical compositions are SiO2, Al2O3, CaO, Fe2O3 and K2O, as well as a small amount of MgO, etc. The SiO2 content is 55-80%. Other raw materials can be obtained commercially.

[0037] Example 1

[0038] A multifunctional soil conditioner for fine-grained copper tailings, the raw materials of which include: 10 parts of fine-grained copper tailings, 8 parts of calcium oxide, 3 parts of potassium hydroxide, 4 parts of sodium hydroxide, 1.2 parts of ethylenediamine phosphate, and 35 parts of deionized water;

[0039] The preparation method of the fine-grained copper tailings multifunctional soil conditioner comprises the following steps:

[0040] (1) Drying of copper tailings. Place fine-grained copper tailings in a drying furnace and dry at 150°C for 30 minutes for later use.

[0041] (2) Crushing and weighing. The dried fine-grained copper tailings are crushed to 200 mesh and weighed accurately for later use.

[0042] (3) Preparation of basic batch materials: Weigh the calcium oxide, potassium hydroxide, sodium hydroxide and ethylenediamine phosphate according to the amount and set aside.

[0043] (4) Grinding and mixing materials. Take the above-mentioned fine-grained copper tailings, calcium oxide, potassium hydroxide, sodium hydroxide and ethylenediamine phosphate, mix and grind them to a fineness of 400 mesh, add deionized water and continue to stir and disperse, and after uniform dispersion, age for 18 hours to obtain a mixed material.

[0044] (5) High temperature calcination: The mixture is calcined at a temperature of 800°C and a calcination time of 90 minutes, followed by cooling.

[0045] (6) Grinding and sieving. Grind and sieve the cooled mixture to a fineness of 200 μm to obtain the multifunctional soil conditioner.

[0046] Example 2

[0047] A multifunctional soil conditioner for fine-grained copper tailings, the raw materials of which include: 15 parts of fine-grained copper tailings, 12 parts of calcium carbonate, 3 parts of potassium hydrogen phosphate, 3 parts of sodium carbonate, 1 part of ethylenediamine phosphate, and 40 parts of deionized water;

[0048] The preparation method of the fine-grained copper tailings multifunctional soil conditioner comprises the following steps:

[0049] (1) Drying of copper tailings. Place fine-grained copper tailings in a drying furnace and dry them at 200°C for 40 minutes for later use.

[0050] (2) Crushing and weighing. The dried fine-grained copper tailings are crushed to 300 mesh and weighed accurately for later use.

[0051] (3) Preparation of basic batch materials: Weigh the calcium carbonate, potassium hydrogen phosphate, sodium carbonate and ethylenediamine phosphate according to the amount and set aside.

[0052] (4) Grinding and mixing of materials. Take the above-mentioned fine-grained copper tailings, calcium carbonate, potassium hydrogen phosphate, sodium carbonate and ethylenediamine phosphate, mix and grind to a fineness of 500 mesh, add deionized water and continue to stir and disperse, and age for 24 hours after uniform dispersion to obtain a mixture. (5) High-temperature roasting. The mixture is roasted at high temperature, the roasting temperature is controlled to be 1000℃, the roasting time is 30 minutes, and then cooled.

[0053] (6) Grinding and sieving. Grind and sieve the cooled mixture to a fineness of 250 μm to obtain the multifunctional soil conditioner.

[0054] Example 3

[0055] A multifunctional soil conditioner of fine-grained copper tailings, the raw materials of which include: 12 parts of fine-grained copper tailings, 8 parts of calcium hydroxide, 2 parts of potassium carbonate, 3 parts of sodium hydrogen phosphate, 1 part of humic acid, and 40 parts of deionized water;

[0056] The preparation method of the fine-grained copper tailings multifunctional soil conditioner comprises the following steps:

[0057] (1) Drying of copper tailings. Place fine-grained copper tailings in a drying furnace and dry at 150°C for 30 minutes for later use.

[0058] (2) Crushing and weighing. The dried fine-grained copper tailings are crushed to 200 mesh and weighed accurately for later use.

[0059] (3) Preparation of basic batch materials: Weigh the calcium hydroxide, potassium carbonate, sodium hydrogen phosphate and humic acid according to the amount and set aside.

[0060] (4) Grinding and mixing materials. Take the above-mentioned fine-grained copper tailings, calcium hydroxide, potassium carbonate, sodium hydrogen phosphate and humic acid, mix and grind them to a fineness of 400 mesh, add deionized water and continue to stir and disperse, and age them for 22 hours after uniform dispersion to obtain a mixed material.

[0061] (5) High temperature calcination: The mixture is calcined at a high temperature, the calcination temperature is controlled to be 900°C, the calcination time is 90 minutes, and then cooled.

[0062] (7) Grinding and sieving. Grind and sieve the cooled mixture to a fineness of 200 μm to obtain the multifunctional soil conditioner.

[0063] Example 4

[0064] A multifunctional soil conditioner for fine-grained copper tailings, the raw materials of which include: 12 parts of fine-grained copper tailings, 10 parts of calcium oxide, 2 parts of potassium hydroxide, 4 parts of sodium hydroxide, 1 part of ethylenediamine phosphate, and 45 parts of deionized water;

[0065] The preparation method of the fine-grained copper tailings multifunctional soil conditioner comprises the following steps:

[0066] (1) Drying of copper tailings. Place fine-grained copper tailings in a drying furnace and dry at 180°C for 30 minutes for later use.

[0067] (2) Crushing and weighing. The dried fine-grained copper tailings are crushed to 200 mesh and weighed accurately for later use.

[0068] (3) Preparation of basic batch materials: Weigh the calcium oxide, potassium hydroxide, sodium hydroxide and ethylenediamine phosphate according to the amount and set aside.

[0069] (4) Grinding and mixing materials. Take the above-mentioned fine-grained copper tailings, calcium oxide, potassium hydroxide, sodium hydroxide and ethylenediamine phosphate, mix and grind them to a fineness of 400 mesh, add deionized water and continue to stir and disperse them, and age them for 21 hours after they are evenly dispersed to obtain a mixed material.

[0070] (5) High temperature calcination: The mixture is calcined at a high temperature, the calcination temperature is controlled to be 900°C, the calcination time is 50 minutes, and then cooled.

[0071] (6) Grinding and sieving. Grind and sieve the cooled mixture to a fineness of 200 μm to obtain the multifunctional soil conditioner.

[0072] Example 5

[0073] The same raw material formula and preparation method as in Example 4 were used, except that ethylenediamine phosphate was replaced by humic acid.

[0074] Comparative Example 1

[0075] The same raw material formula and preparation method as in Example 4 were used, except that the amount of fine-grained copper tailings used was 20 parts.

[0076] Comparative Example 2

[0077] The same raw material formula and preparation method as in Example 4 were used, except that the amount of calcium oxide used was 18 parts.

[0078] Comparative Example 3

[0079] The same raw material formula and preparation method as in Example 4 were used, except that 6 parts of potassium hydroxide were used.

[0080] Comparative Example 4

[0081] The same raw material formula and preparation method as in Example 4 were used, except that 8 parts of sodium hydroxide were used.

[0082] Comparative Example 5

[0083] The same raw material formula and preparation method as in Example 4 were used, except that the amount of ethylenediaminephosphonate used was 2 parts.

[0084] Comparative Example 6

[0085] The same raw material formula and preparation method as in Example 4 were used, except that calcium oxide was not added.

[0086] Comparative Example 7

[0087] The same raw material formula and preparation method as in Example 4 were used, except that potassium hydroxide was not added.

[0088] Comparative Example 8

[0089] The same raw material formula and preparation method as in Example 4 were used, except that no sodium hydroxide was added.

[0090] Comparative Example 9

[0091] The same raw material formula and preparation method as in Example 4 were used, except that ethylenediamine phosphate was not added.

[0092] Comparative Example 10

[0093] The same raw material formula and preparation method as in Example 4 were used, except that the grinding fineness in step (4) of the non-preparation method was 300 mesh.

[0094] Comparative Example 11

[0095] The same raw material formula and preparation method as in Example 4 were used, except that the calcination temperature in step (5) of the preparation method was 500°C.

[0096] Comparative Example 12

[0097] The same raw material formula and preparation method as in Example 4 were used, except that the calcination temperature in step (5) of the preparation method was 1200°C.

[0098] Performance Testing

[0099] The test method in the industry standard "NY / T797-2004 Silicon Fertilizer" was used to test the effective silicon content, moisture content and fineness of the samples. The results are shown in Table 1.

[0100] Table 1 Performance test results of various embodiments and comparative examples

[0101]

[0102] Results Analysis

[0103] By comparing Examples 1-4, it can be seen that the soil conditioner obtained by adopting the technical solution of the present invention has an effective silicon content, a moisture content and a fineness that meet and far exceeds the requirements of industry standards, truly realizing the resource utilization of copper tailings, and obtaining a high-quality silicon fertilizer soil conditioner that can be marketed and used.

[0104] By comparing Example 4 and Example 5, it can be seen that, for the organic activator, the use of ethylenediamine phosphate is more conducive to the activation of copper tailings, because ethylenediamine phosphate has a better activation effect on the bound copper oxide and free copper oxide in the copper tailings than humic acid.

[0105] By comparing Example 4 with Comparative Examples 1-9, it can be seen that the raw material components in the present invention are all reasonably configured, and the amount of raw materials exceeding the range or the lack of a certain raw material will lead to a decrease in product performance. This is because in this technology, the copper tailings and the calcium activator, potassium activator, sodium activator and organic activator cooperate with each other, and each activator plays its own activation role while promoting each other, so that each element in the copper tailings is fully activated, and a soil conditioner with a higher effective silicon content is obtained.

[0106] By comparing Example 4 and Comparative Example 10, it can be seen that when the powder is fully ground to a suitable fineness during the preparation process, the contact area of ​​the components is larger, the interface activation reaction is more complete, and the effective silicon content in the product is higher. In addition, the suitable fineness will also affect the fineness of the final product. The coarser the grinding fineness during the process, the incomplete activation reaction during the subsequent calcination process, resulting in a decrease in the uniformity of the particles of the final product.

[0107] It can be seen from Comparative Example 4 and Comparative Examples 11 and 12 that the present invention strictly controls the calcination temperature at 800-1000° C., at which temperature the activation reaction is most complete, and the obtained silicon fertilizer has the highest effective silicon content, lower moisture content, and more uniform fineness.

[0108] In summary, the present invention mainly treats tailings by mechanical and chemical composite excitation in the basic batch preparation and high-temperature roasting stages, so that the inert components therein are converted into effective active components that are beneficial to plant absorption, and finally a multifunctional soil conditioner product is produced.

[0109] Those skilled in the art should understand that the above embodiments are merely exemplary embodiments and that various changes, substitutions and alterations may be made without departing from the spirit and scope of the present application.

Claims

1. A multifunctional soil conditioner for fine-grained copper tailings, characterized in that: The raw materials are composed of the following components: 12 parts of fine-grained copper tailings, 10 parts of calcium oxide, 2 parts of potassium hydroxide, 4 parts of sodium hydroxide, 1 part of ethylenediamine phosphate, and 45 parts of deionized water; The preparation method of the fine-grained copper tailings multifunctional soil conditioner comprises the following steps: (1) Drying of copper tailings: Place fine-grained copper tailings in a drying furnace and dry at 180°C for 30 minutes for later use; (2) Crushing and weighing: crush the dried fine-grained copper tailings to 200 mesh, weigh accurately and set aside; (3) Preparation of basic batch materials, weighing the calcium oxide, potassium hydroxide, sodium hydroxide and ethylenediamine phosphate according to the amount, set aside; (4) Grinding and mixing the materials: taking the above-mentioned fine-grained copper tailings, calcium oxide, potassium hydroxide, sodium hydroxide and ethylenediamine phosphate, mixing and grinding to a fineness of 400 mesh, adding deionized water and continuing to stir and disperse, aging for 21 hours after uniform dispersion, and obtaining a mixture; (5) high temperature calcination, the mixture is calcined at a high temperature, the calcination temperature is controlled to be 900°C, the calcination time is 50min, and cooling; (6) Grinding and sieving: Grinding and sieving the cooled mixture to a fineness of 200 μm to obtain the multifunctional soil conditioner.

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