Phosphogypsum active agent as well as preparation method and application thereof

Abstract

The invention provides an ardealite active agent as well as a preparation method and application thereof. The ardealite active agent is prepared from the following raw materials: silica sol, polyacrylamide, n-octyltriethoxysilane, polyferric sulfate, sodium lignin sulfonate, butyl acrylate, an alkali activator, a cross-linking agent and water. According to the method, the content of soluble phosphorus in the leachate of the treated ardealite can be smaller than 0.5 mg / L, the content of soluble fluorine in the leachate of the treated ardealite can be smaller than 10 mg / L, the first-level standard of Integrated Wastewater Discharge Standard GB 8978-1996 is met, harmless treatment of the ardealite is achieved, and the preparation method is simple, easy to operate and suitable for large-scale popularization and application.

Description

Technical Field

[0001] The present invention belongs to the technical field of phosphogypsum treatment, and particularly relates to a phosphogypsum activator, a preparation method thereof, and an application thereof. Background Art

[0002] Phosphogypsum is a solid waste generated in the wet-process phosphoric acid industry. Its main component is calcium sulfate dihydrate (CaSO4·2H2O), and it also contains harmful chemical substances such as unextracted phosphate rock, residual phosphoric acid, fluorides, acid-insoluble substances, and some heavy metals. These harmful chemical substances will cause serious pollution to the environment, soil, air, water quality, human body, animals and plants, and the stacking of phosphogypsum will also cause a large waste of land resources. However, at present, the harmless treatment of phosphogypsum fails to meet the standards in many cases, which will affect the comprehensive utilization of phosphogypsum. Summary of the Invention

[0003] In view of this, the present invention provides a phosphogypsum activator, a preparation method thereof, and an application thereof, which can make the soluble phosphorus content in the leachate of the treated phosphogypsum less than 0.5 mg / L and the soluble fluorine content less than 10 mg / L, reaching the first-class standard of the Comprehensive Wastewater Discharge Standard GB 8978-1996, realizing the harmless treatment of phosphogypsum, and the preparation method is simple, easy to operate, and suitable for large-scale popularization and application.

[0004] To achieve the above object, the present invention adopts the following technical solutions: On the one hand, the present invention provides a phosphogypsum activator, comprising the following raw materials: silica sol, polyacrylamide, n-octyltriethoxysilane, polymeric ferric sulfate, sodium lignosulfonate, butyl acrylate, alkaline activator, crosslinking agent, and water.

[0005] Preferably, by weight, the phosphogypsum activator comprises the following raw materials: 60-80 parts of silica sol, 1-3 parts of polyacrylamide, 10-14 parts of n-octyltriethoxysilane, 5-9 parts of polymeric ferric sulfate, 2-4 parts of sodium lignosulfonate, 3-7 parts of butyl acrylate, 2-4 parts of alkaline activator, 6-8 parts of crosslinking agent, and 15-35 parts of water.

[0006] Preferably, the alkaline activator comprises sodium hydroxide; and / or, the crosslinking agent comprises silicone resin; and / or, the water comprises deionized water.

[0007] On the other hand, the present invention provides a preparation method of the phosphogypsum activator, comprising the following steps: S1. Mix the alkaline activator and the water to obtain an alkaline aqueous solution; S2. Add sodium lignosulfonate, polyferric sulfate, octyltriethoxysilane, polyacrylamide, butyl acrylate, silica sol and a crosslinking agent to the alkaline aqueous solution in sequence and mix them to obtain a phosphogypsum activator.

[0008] Preferably, step S1 includes: adding the alkaline activator to the water at a temperature of 100 - 105 °C, and stirring to obtain an alkaline aqueous solution.

[0009] Preferably, in step S1, the stirring speed is 2000 - 2500 r / min, and the stirring time is 5 - 10 min.

[0010] Preferably, step S2 includes: S21. Add sodium lignosulfonate to the alkaline aqueous solution at a temperature of 80 - 85 °C, and stir to obtain a first mixture; S22. Add polyferric sulfate to the first mixture at a temperature of 60 - 65 °C, and stir to obtain a second mixture; S23. Add octyltriethoxysilane to the second mixture at a temperature of 50 - 55 °C, and stir to obtain a third mixture; S24. Add polyacrylamide to the third mixture at a temperature of 40 - 45 °C, and stir to obtain a fourth mixture; S25. Add butyl acrylate to the fourth mixture at a temperature of 30 - 35 °C, and stir to obtain a fifth mixture; S26. Add silica sol to the fifth mixture at a temperature of 15 - 25 °C, and stir to obtain a sixth mixture; S27. Add the crosslinking agent to the sixth mixture, and stir to obtain a seventh mixture; S28. Let the seventh mixture stand to obtain a phosphogypsum activator.

[0011] Preferably, in step S21, the stirring speed is 2000 - 2500 r / min, and the stirring time is 5 - 10 min; and / or, in step S22, the stirring speed is 2000 - 2500 r / min, and the stirring time is 10 - 15 min; and / or, in step S23, the stirring speed is 1500 - 2000 r / min, and the stirring time is 10 - 15 min; and / or, in step S24, the stirring speed is 2000 - 2500 r / min, and the stirring time is 5 - 10 min; and / or, In step S25, the stirring speed is 1500 - 2000 r / min, and the stirring time is 3 - 5 min; and / or, In step S26, the stirring speed is 2000 - 2500 r / min, and the stirring time is 20 - 25 min; and / or, In step S27, the stirring speed is 2000 - 2500 r / min, and the stirring time is 10 - 15 min.

[0012] Preferably, in step S28, the standing time is 30 - 40 min.

[0013] On the other hand, the present invention provides an application of the phosphogypsum activator or the phosphogypsum activator prepared by the preparation method of the phosphogypsum activator in the harmless treatment of phosphogypsum.

[0014] Compared with the prior art, the beneficial effects of the present invention are as follows: (1) The phosphogypsum activator provided by the present invention can enable the physical and chemical reaction processes of neutralization, purification and ion exchange of phosphogypsum, effectively remove harmful chemical impurities in phosphogypsum, and can make the soluble phosphorus content in the leachate of phosphogypsum treated with the phosphogypsum activator less than 0.5 mg / L, and the soluble fluorine content less than 10 mg / L, reaching the first-class standard of the Comprehensive Wastewater Discharge Standard GB 8978 - 1996, realizing the harmless treatment of phosphogypsum. The treated phosphogypsum can be widely used in fields such as cement retarders, mine ecological restoration, soil improvement, site backfilling, road bases and municipal engineering, etc., and can improve the comprehensive utilization of phosphogypsum.

[0015] (2) The raw materials of the phosphogypsum activator provided by the present invention are easily available, the preparation method is simple, easy to operate, and the use effect of the prepared phosphogypsum activator is good, which is suitable for large-scale popularization and application. Specific Embodiments

[0016] The following combines specific embodiments to further elaborate the present invention in detail, so that those skilled in the art can understand the present invention more clearly.

[0017] On the one hand, the present invention provides a phosphogypsum activator, which comprises the following raw materials: silica sol, polyacrylamide, n-octyltriethoxysilane, polyferric sulfate, sodium lignosulfonate, butyl acrylate, alkaline activator, crosslinking agent and water.

[0018] The phosphogypsum activator provided by the present invention can enable physical and chemical reaction processes of neutralization, purification, and ion exchange of phosphogypsum, effectively remove harmful chemicals and impurities in phosphogypsum, and can make the soluble phosphorus content in the leachate of phosphogypsum treated with the phosphogypsum activator less than 0.5 mg / L and the soluble fluorine content less than 10 mg / L, meeting the first-class standard of the Comprehensive Wastewater Discharge Standard GB 8978-1996, realizing the harmless treatment of phosphogypsum. The treated phosphogypsum can be widely used in fields such as cement retarders, mine ecological restoration, soil improvement, site backfilling, road bases, and municipal engineering, which can improve the comprehensive utilization of phosphogypsum. It can be understood that neutralization is an acid-base neutralization reaction, purification is a flocculation precipitation reaction, and ion exchange is a chemical reaction in which cations and anions combine to form insoluble substances.

[0019] Further, by weight, the phosphogypsum activator comprises the following raw materials: 60-80 parts of silica sol, 1-3 parts of polyacrylamide, 10-14 parts of n-octyltriethoxysilane, 5-9 parts of polymeric ferric sulfate, 2-4 parts of sodium lignosulfonate, 3-7 parts of butyl acrylate, 2-4 parts of alkaline activator, 6-8 parts of crosslinking agent, and 15-35 parts of water. Using the above weight parts of the raw materials of the phosphogypsum activator is beneficial to ensuring the effect of phosphogypsum treatment.

[0020] Further, the alkaline activator comprises sodium hydroxide. Using sodium hydroxide as the alkaline activator is beneficial to improving the effect of phosphogypsum treatment.

[0021] Further, the crosslinking agent comprises silicone resin.

[0022] Further, the water comprises deionized water.

[0023] On the other hand, the present invention provides a preparation method of the phosphogypsum activator, comprising the following steps: S1. Mix the alkaline activator and the water to obtain an alkaline aqueous solution; S2. Sequentially add the sodium lignosulfonate, polymeric ferric sulfate, n-octyltriethoxysilane, polyacrylamide, butyl acrylate, silica sol, and crosslinking agent to the alkaline aqueous solution and mix to obtain the phosphogypsum activator.

[0024] Using the above steps to prepare the phosphogypsum activator can ensure the use effect of the prepared phosphogypsum activator, and the preparation method is simple and easy to operate. It should be noted that adding the sodium lignosulfonate, polyferric sulfate, octyltriethoxysilane, polyacrylamide, butyl acrylate, silica sol and crosslinking agent to the alkaline aqueous solution in sequence means adding the sodium lignosulfonate to the alkaline aqueous solution and mixing, adding the polyferric sulfate and mixing, adding the octyltriethoxysilane and mixing, adding the polyacrylamide and mixing, adding the butyl acrylate and mixing, adding the silica sol and mixing, adding the crosslinking agent and mixing, and mixing is carried out after adding each raw material.

[0025] Further, step S1 includes: adding the alkaline activator to the water at a temperature of 100 - 105 °C and stirring to obtain an alkaline aqueous solution. Stirring and mixing the water at the above temperature with the alkaline activator is beneficial to improving the quality of the prepared phosphogypsum activator.

[0026] Further, in step S1, the stirring speed is 2000 - 2500 r / min, and the stirring time is 5 - 10 min. Stirring at the above speed and time is beneficial to improving the quality of the prepared phosphogypsum activator and also beneficial to taking into account the energy consumption.

[0027] Further, step S2 includes: S21. Adding sodium lignosulfonate to the alkaline aqueous solution at a temperature of 80 - 85 °C and stirring to obtain a first mixed solution; S22. Adding polyferric sulfate to the first mixed solution at a temperature of 60 - 65 °C and stirring to obtain a second mixed solution; S23. Adding octyltriethoxysilane to the second mixed solution at a temperature of 50 - 55 °C and stirring to obtain a third mixed solution; S24. Adding polyacrylamide to the third mixed solution at a temperature of 40 - 45 °C and stirring to obtain a fourth mixed solution; S25. Adding butyl acrylate to the fourth mixed solution at a temperature of 30 - 35 °C and stirring to obtain a fifth mixed solution; S26. Adding silica sol to the fifth mixed solution at a temperature of 15 - 25 °C and stirring to obtain a sixth mixed solution; S27. Adding the crosslinking agent to the sixth mixed solution and stirring to obtain a seventh mixed solution; S28. Standing the seventh mixed solution to obtain the phosphogypsum activator.

[0028] Adding the sodium lignosulfonate, polyferric sulfate, octyltriethoxysilane, polyacrylamide, butyl acrylate, silica sol and crosslinking agent to the alkaline aqueous solution in sequence by the above steps and mixing them to obtain the phosphogypsum activator is beneficial to improving the quality of the obtained phosphogypsum activator and also beneficial to taking into account the energy consumption. It can be understood that the phosphogypsum activator can be prepared using a stirring reaction kettle, which is convenient for operation, easy to control, and beneficial to improving the production efficiency of the phosphogypsum activator.

[0029] Further, in step S21, the stirring speed is 2000 - 2500 r / min and the stirring time is 5 - 10 min.

[0030] Further, in step S22, the stirring speed is 2000 - 2500 r / min and the stirring time is 10 - 15 min.

[0031] Further, in step S23, the stirring speed is 1500 - 2000 r / min and the stirring time is 10 - 15 min.

[0032] Further, in step S24, the stirring speed is 2000 - 2500 r / min and the stirring time is 5 - 10 min.

[0033] Further, in step S25, the stirring speed is 1500 - 2000 r / min and the stirring time is 3 - 5 min.

[0034] Further, in step S26, the stirring speed is 2000 - 2500 r / min and the stirring time is 20 - 25 min.

[0035] Further, in step S27, the stirring speed is 2000 - 2500 r / min and the stirring time is 10 - 15 min.

[0036] Further, in step S28, the standing time is 30 - 40 min.

[0037] On the other hand, the present invention provides an application of the phosphogypsum activator or the phosphogypsum activator prepared by the preparation method of the phosphogypsum activator in the harmless treatment of phosphogypsum.

[0038] Example 1 A phosphogypsum activator comprises the following raw materials: 600 g of nano - silica (silica sol), 10 g of polyacrylamide, 100 g of octyltriethoxysilane, 50 g of polyferric sulfate, 20 g of sodium lignosulfonate, 30 g of butyl acrylate, 20 g of sodium hydroxide, 60 g of methyl silicone resin (organosilicon resin) and 150 g of deionized water; The preparation method of the phosphogypsum activator comprises the following steps: S1. Add deionized water into a stirring reactor, control the temperature at 100 °C, put in sodium hydroxide, and stir at a speed of 2000 r / min for 5 min to obtain an alkaline aqueous solution; S21. When the temperature of the alkaline aqueous solution in the stirring reactor drops to 80 °C, put in sodium lignosulfonate, and stir at a speed of 2000 r / min for 5 min to obtain a first mixed solution; S22. When the temperature of the first mixed solution in the stirring reactor drops to 60 °C, put in polyferric sulfate, and stir at a speed of 2000 r / min for 10 min to obtain a second mixed solution; S23. When the temperature of the second mixed solution in the stirring reactor drops to 50 °C, put in n-octyltriethoxysilane, and stir at a speed of 1500 r / min for 10 min to obtain a third mixed solution; S24. When the temperature of the third mixed solution in the stirring reactor drops to 40 °C, put in polyacrylamide, and stir at a speed of 2000 r / min for 5 min to obtain a fourth mixed solution; S25. When the temperature of the fourth mixed solution in the stirring reactor drops to 30 °C, put in butyl acrylate, and stir at a speed of 1500 r / min for 3 min to obtain a fifth mixed solution; S26. When the temperature of the fifth mixed solution in the stirring reactor drops to 15 °C, put in nano-silica (silica sol), and stir at a speed of 2000 r / min for 20 min to obtain a sixth mixed solution; S27. Put in methyl silicone resin (organosilicon resin) into the sixth mixed solution in the stirring reactor, and stir at a speed of 2000 r / min for 10 min to obtain a seventh mixed solution; S28. Let the seventh mixed solution in the stirring reactor stand for 30 min to obtain the phosphogypsum activator.

[0039] Example 2 A phosphogypsum activator has the same raw materials and preparation method as in Example 1, except that the nano-silica (silica sol) is 700 g, the polyacrylamide is 20 g, the n-octyltriethoxysilane is 120 g, the polyferric sulfate is 70 g, the sodium lignosulfonate is 30 g, the butyl acrylate is 50 g, the sodium hydroxide is 30 g, the methyl silicone resin (organosilicon resin) is 70 g, and the deionized water is 250 g.

[0040] Example 3 A phosphogypsum activator has the same raw materials and preparation method as in Example 1, except that the nano-silica (silica sol) is 800 g, polyacrylamide is 30 g, n-octyltriethoxysilane is 140 g, polymeric ferric sulfate is 90 g, sodium lignosulfonate is 40 g, butyl acrylate is 70 g, sodium hydroxide is 40 g, methyl silicone resin (organosilicon resin) is 80 g, and deionized water is 350 g.

[0041] Example 4 A phosphogypsum activator has the same raw materials as in Example 1, except that the preparation method of the phosphogypsum activator includes the following steps: S1. Add deionized water to a stirring reactor, control the temperature at 105 °C, add sodium hydroxide, and stir at a speed of 2500 r / min for 10 min to obtain an alkaline aqueous solution; S21. When the temperature of the alkaline aqueous solution in the stirring reactor drops to 85 °C, add sodium lignosulfonate and stir at a speed of 2500 r / min for 10 min to obtain a first mixed solution; S22. When the temperature of the first mixed solution in the stirring reactor drops to 65 °C, add polymeric ferric sulfate and stir at a speed of 2500 r / min for 15 min to obtain a second mixed solution; S23. When the temperature of the second mixed solution in the stirring reactor drops to 55 °C, add n-octyltriethoxysilane and stir at a speed of 2000 r / min for 15 min to obtain a third mixed solution; S24. When the temperature of the third mixed solution in the stirring reactor drops to 45 °C, add polyacrylamide and stir at a speed of 2500 r / min for 10 min to obtain a fourth mixed solution; S25. When the temperature of the fourth mixed solution in the stirring reactor drops to 35 °C, add butyl acrylate and stir at a speed of 2000 r / min for 5 min to obtain a fifth mixed solution; S26. When the temperature of the fifth mixed solution in the stirring reactor drops to 25 °C, add nano-silica (silica sol) and stir at a speed of 2500 r / min for 25 min to obtain a sixth mixed solution; S27. Add methyl silicone resin (organosilicon resin) to the sixth mixed solution in the stirring reactor and stir at a speed of 2500 r / min for 15 min to obtain a seventh mixed solution; S28. Let the seventh mixed solution in the stirring reactor stand for 40 min to obtain the phosphogypsum activator.

[0042] Comparative Example 1 A phosphogypsum activator contains calcium oxide.

[0043] Comparative Example 2 A phosphogypsum activator has the same raw materials as in Example 1. The difference lies in that the preparation method of the phosphogypsum activator includes the following steps: S1. Add deionized water to a stirring reactor, control the temperature at 100 °C, add sodium hydroxide, and stir at a speed of 2000 r / min for 5 min to obtain an alkaline aqueous solution; S21. When the temperature of the alkaline aqueous solution in the stirring reactor drops to 80 °C, add sodium lignosulfonate, polyferric sulfate, n-octyltriethoxysilane, polyacrylamide, butyl acrylate, nano-silica (silica sol), and methyl silicone resin (organosilicon resin) into the alkaline aqueous solution, and stir at a speed of 2000 r / min for 63 min to obtain a mixed solution; S22. Let the mixed solution in the stirring reactor stand for 30 min to obtain the phosphogypsum activator.

[0044] Comparative Example 3 A phosphogypsum activator has the same raw materials as in Example 1. The difference lies in that the preparation method of the phosphogypsum activator includes the following steps: S1. Add deionized water to a stirring reactor, control the temperature at 100 °C, and add sodium hydroxide, sodium lignosulfonate, polyferric sulfate, n-octyltriethoxysilane, polyacrylamide, butyl acrylate, nano-silica (silica sol), and methyl silicone resin (organosilicon resin) into the deionized water, and stir at a speed of 2000 r / min for 68 min to obtain a mixed solution; S2. Let the mixed solution in the stirring reactor stand for 30 min to obtain the phosphogypsum activator.

[0045] Performance Test and Results Use the phosphogypsum activators prepared in Examples 1 to 4 and Comparative Examples 1 to 3 to carry out harmless treatment on phosphogypsum. The harmless treatment of phosphogypsum includes the following steps: Slurry 500 g of washed phosphogypsum with 1500 g of water to obtain a phosphogypsum slurry; Add 20 g of the phosphogypsum activator to the phosphogypsum slurry, stir and react for 30 min, and filter to obtain harmless phosphogypsum.

[0046] The contents of soluble phosphorus and soluble fluorine in the harmless phosphogypsum treated with the phosphogypsum activators prepared in Examples 1 to 4 and Comparative Examples 1 to 3 were detected respectively. Among them, the soluble phosphorus was detected according to the "CJ / T 51-2018 Urban Sewage Quality Standard Inspection Method - Stannous Chloride Spectrophotometry" to determine the phosphorus content in the leaching solution of the harmless phosphogypsum, and the soluble fluorine was detected according to the "GB / T 15555.11-1995 Determination of Fluoride in Solid Wastes - Ion Selective Electrode Method" to determine the fluorine content in the leaching solution of the harmless phosphogypsum; the sample preparation method for the leaching solution of the harmless phosphogypsum was: the harmless phosphogypsum sample was prepared into a leaching solution according to the sample preparation standard cited in the "GB 18599-2020 General Industrial Solid Waste Storage and Landfill Pollution Control Standard" (the "HJ 557-2010 Solid Waste Leaching Toxicity Leaching Method Horizontal Oscillation Method"); the results are shown in Table 1.

[0047] Table 1 Detection Results of Harmless Phosphogypsum Treated in Each Example and Comparative Example

[0048] Conclusion: As can be seen from Table 1, the contents of soluble phosphorus and soluble fluorine detected in the harmlessness of the phosphogypsum modified with the phosphogypsum activators prepared in Comparative Examples 1 to 3 do not meet the requirements. The contents of soluble phosphorus and soluble fluorine detected in the harmlessness of the phosphogypsum modified with the phosphogypsum activators prepared in Examples 1 to 4 are respectively lower than 0.5 mg / L and 10 mg / L, both of which meet the requirements.

[0049] In the present invention, the specific raw materials not described are all existing substances and can be directly purchased from the market.

[0050] The above are only the preferred implementation schemes of the present invention and are not used to limit the protection scope of the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A phosphogypsum active agent, characterized in that: The invention comprises the following raw materials: silica sol, polyacrylamide, n-octyltriethoxysilane, polymerized ferric sulfate, sodium lignin sulfonate, butyl acrylate, alkaline activator, cross-linking agent and water.

2. The phosphogypsum active agent according to claim 1, characterized in that: The phosphogypsum activator comprises the following raw materials in parts by weight: 60-80 parts of silica sol, 1-3 parts of polyacrylamide, 10-14 parts of n-octyltriethoxysilane, 5-9 parts of polymerized ferric sulfate, 2-4 parts of sodium lignin sulfonate, 3-7 parts of butyl acrylate, 2-4 parts of alkaline activator, 6-8 parts of cross-linking agent and 15-35 parts of water.

3. The phosphogypsum active agent according to claim 1, characterized in that: The alkaline activator comprises sodium hydroxide; and / or, The cross-linking agent comprises a silicone resin; and / or, The water includes deionized water.

4. The method for preparing the phosphogypsum active agent according to any one of claims 1 to 3, characterized in that: The following steps are involved: S1, mixing the alkaline activator and the water to obtain an alkaline aqueous solution; S2. Add the sodium lignin sulfonate, polyferric sulfate, n-octyltriethoxysilane, polyacrylamide, butyl acrylate, silica sol and cross-linking agent to the alkaline aqueous solution in sequence and mix to obtain a phosphogypsum active agent.

5. The method for preparing the phosphogypsum active agent according to claim 4, characterized in that: Step S1 comprises: adding the alkaline activator into the water at a temperature of 100-105° C., stirring, and obtaining an alkaline aqueous solution.

6. The method for preparing the phosphogypsum active agent according to claim 5, characterized in that: In step S1, the stirring speed is 2000-2500 r / min, and the stirring time is 5-10 min.

7. The method for preparing the phosphogypsum active agent according to claim 5 or 6, characterized in that: Step S2 includes: S21, adding sodium lignin sulfonate to the alkaline aqueous solution at a temperature of 80-85° C., stirring, to obtain a first mixed solution; S22, adding polyferric sulfate to the first mixed solution at a temperature of 60-65° C., stirring, to obtain a second mixed solution; S23, adding n-octyltriethoxysilane to the second mixed solution at a temperature of 50-55° C., stirring, to obtain a third mixed solution; S24, adding polyacrylamide to the third mixed solution at a temperature of 40-45° C., stirring, to obtain a fourth mixed solution; S25, adding butyl acrylate to the fourth mixed solution at a temperature of 30-35° C., stirring, to obtain a fifth mixed solution; S26, adding silica sol to the fifth mixed solution at a temperature of 15-25° C., stirring, to obtain a sixth mixed solution; S27, adding the cross-linking agent to the sixth mixed solution, stirring, to obtain a seventh mixed solution; S28, allowing the seventh mixed solution to stand to obtain a phosphogypsum activator.

8. The method for preparing the phosphogypsum active agent according to claim 7, characterized in that: In step S21, the stirring speed is 2000-2500 r / min, and the stirring time is 5-10 min; and / or, In step S22, the stirring speed is 2000-2500 r / min, and the stirring time is 10-15 min; and / or, In step S23, the stirring speed is 1500-2000 r / min, and the stirring time is 10-15 min; and / or, In step S24, the stirring speed is 2000-2500 r / min, and the stirring time is 5-10 min; and / or, In step S25, the stirring speed is 1500-2000 r / min, and the stirring time is 3-5 min; and / or, In step S26, the stirring speed is 2000-2500 r / min, and the stirring time is 20-25 min; and / or, In step S27, the stirring speed is 2000-2500 r / min, and the stirring time is 10-15 min.

9. The method for preparing the phosphogypsum active agent according to claim 7, characterized in that: In step S28, the standing time is 30 to 40 minutes.

10. Use of the phosphogypsum activator according to any one of claims 1 to 3 or the phosphogypsum activator prepared by the preparation method of the phosphogypsum activator according to any one of claims 4 to 9 in the harmless treatment of phosphogypsum.

Images