Processing method of safe fluorgypsum powder

Abstract

The invention discloses a treatment method of safe fluorgypsum powder, and belongs to the technical field of fluorgypsum. The treatment method of the fluorgypsum comprises the following steps: S1, adding the fluorgypsum into water containing calcium carbonate, and stirring; s2, then adding organic acid calcium salt and continuously stirring; and S3, adding calcium hydroxide, and continuously stirring to obtain the treated fluorgypsum. The method provided by the invention can efficiently remove residual acid, residual fluorine and heavy metal impurities in the fluorgypsum.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of fluorogypsum, in particular to a treatment method of safe fluorogypsum powder. BACKGROUND

[0002] The common harmless treatment method of fluorogypsum is that the acid fluorogypsum discharged in the production of hydrogen fluoride is mixed with calcium oxide, and then directly used after being stacked for 7 days to 1 month; some are also calcined at a high temperature of 200℃ to 600℃, and finally used as building gypsum after being ground.

[0003] This treatment method cannot completely remove sulfuric acid, hydrogen fluoride and other acidic substances in the fluorogypsum crystals, and has potential toxic hazards. The treated building fluorogypsum powder has a distinct irritating odor, and the fluorogypsum powder releases residual acid, residual fluorine and heavy metals after being soaked in water, which is not environmentally friendly and safe.

[0004] 1) The building fluorogypsum powder and slurry have a distinct irritating odor.

[0005] 2) The building fluorogypsum powder has residual acid and residual fluorine.

[0006] 3) Acidic gases are discharged during the calcination process, which is not environmentally friendly.

[0007] 4) The building fluorogypsum powder has soluble heavy metals.

[0008] 5) The acid fluorogypsum needs to be mixed with calcium oxide powder (or calcium hydroxide) and stacked for a sufficient time to be modified into usable building fluorogypsum, which is time-consuming and inefficient.

[0009] Fluorogypsum is a by-product of the production process of hydrofluoric acid, which is a waste residue mainly composed of calcium sulfate generated by the reaction of sulfuric acid and fluorite powder, and is mainly produced by hydrofluoric acid manufacturers.

[0010] The preparation process of hydrofluoric acid is to react fluorite powder with sulfuric acid in a hydrogen fluoride reactor to generate hydrogen fluoride, and the reaction equation is as follows: H2SO4 + CaF2 → 2HF + CaSO4 Due to the presence of impurities such as SiO2, calcium carbonate, metal oxides, metal sulfides and oleic acid in fluorite, the following side reactions also occur: SiO2 + 4HF → SiF4 + H2O SiF4 + 2HF → H2SiF6 CaCO3 + H2SO4 → CaSO4 + CO2 + H2O M2O3 + H2SO4 → M2(SO4)3 + 3H2O MS + H2SO4 → H2S + MSO4 H2S + H2SO4 → S + SO2 + 2H2O C 17 H 33 COOH + 51H2SO4 → 18CO2 + 51SO2 + 68H2O The fluorogypsum is produced in a large amount, about 3.6-4.5 tons of fluorogypsum is produced per ton of hydrofluoric acid.

[0011] The fluorogypsum crystal is smaller than the natural dihydrate gypsum, generally being a microcrystal of several microns to tens of microns. The main phase of the phase is type II anhydrite, and the impurity phase is CaF2, dihydrate gypsum, etc.

[0012] When the production device is just out, the main component of the fluorogypsum is anhydrite (CaSO4), and contains a small amount of CaF2, a small amount of HF and H2SO4 which are not completely reacted, a small amount of SiF4 and H2S impurities which are not discharged or remain in the fluorogypsum lattice, and a small amount of flotation agent oleic acid, etc. Exceeding the limit value specified in the hazardous waste identification standard, it is a harmful solid waste with strong corrosion, which has great side effects on soil, plants, animals and humans.

[0013] Most of the fluorogypsum of the hydrogen fluoride plant is treated by calcium oxide and then stacked or landfilled as general solid waste, which not only wastes land resources and brings huge economic pressure to the enterprise, but also causes the transfer of harmful substances remaining in the fluorogypsum in the stack yard under the action of rainwater leaching and wind scouring, polluting surface and underground water and seriously endangering human health.

[0014] Some factories directly mix the acid fluorogypsum with calcium oxide and then store it in the yard for a long time before crushing and grinding, and use it as a cement retarder. Some acid fluorogypsum is mixed with calcium oxide, calcined at a high temperature of 200-600°C and then ground, and used as building gypsum.

[0015] Although the above several methods can consume fluorogypsum, they have long neutralization treatment time, high energy consumption, are not environmentally friendly and have potential toxic hazards.

[0016] Moreover, the use amount of fluorogypsum accounts for a small proportion, which cannot fundamentally solve the harm caused by the large amount of fluorogypsum stacking, and cannot green, environmentally friendly and efficiently solve the problem of fluorogypsum resource utilization.

[0017] In the hydrogen fluoride production process, calcium sulfate, a reaction product, will continuously deposit on the surface of fluorite. H2SO4 needs to pass through the calcium sulfate layer on the surface of fluorite to further react with fluorite, resulting in the existence of H2SO4 between the calcium sulfate lattices of fluorogypsum.

[0018] After the hydrogen fluoride plant absorbs the tail gas, it is transported to the storage warehouse for long-term storage and aging after being pre-mixed and neutralized by calcium oxide. Some will be further dried at high temperature to minimize the residual volatile gas. The residual H2SO4 in the fluorogypsum lattice and a small amount of other by-products containing fluorine or sulfur heteroacids cannot be timely excluded, which has potential hazards. Especially when used as building gypsum, the residual fluorine, hydrogen and other dangerous elements in fluorogypsum will be released, resulting in unsafe building materials, irritating odor and increased toxicity. SUMMARY

[0019] The purpose of the present application is to overcome the above technical deficiencies and provide a safe fluorogypsum powder treatment method to solve the technical problem of how to efficiently remove residual acid and fluorine and heavy metal impurities in fluorogypsum powder in the prior art.

[0020] To achieve the above technical purpose, the technical scheme of the present application provides a safe fluorogypsum powder treatment method, comprising the following steps: S1, adding fluorogypsum to water containing calcium carbonate and stirring; The main reactions involved are: 2HF + CaCO3 → CaF2 + CO2 + H2O H2SO4 + CaCO3 + H2O → CaSO4·2H2O + CO2 S2, then add organic acid calcium salt and continue stirring; The main reactions involved are: 2F - +Ca 2+ → CaF2 S3, then add calcium hydroxide and continue stirring to obtain treated fluorogypsum.

[0021] The main reactions involved are: M 2+ +2OH - → M(OH)2 M 3+ +3OH - →M(OH)3 M represents a metal element.

[0022] In any embodiment, in step S1, the fluorogypsum is added to water containing calcium carbonate and stirred for 10-20 min at a stirring speed of 10-30 r / min.

[0023] In any embodiment, in step S2, the organic acid calcium salt is added and continues to stir for 2-3 min at a stirring speed of 50-100 r / min.

[0024] In any embodiment, in step S3, the time for adding calcium hydroxide and continuing stirring is 2-3 minutes, and the stirring speed is 50-100 r / min.

[0025] In any embodiment, in step S2, the calcium salt of organic acid is one or more of calcium formate, calcium acetate, calcium propionate and calcium ascorbate.

[0026] In any embodiment, in step S3, calcium hydroxide is added to continue stirring to adjust the pH value of the slurry to 10-12.

[0027] In any embodiment, in step S1, the fineness of calcium carbonate added to the water containing calcium carbonate is 325-800 mesh.

[0028] In any embodiment, in step S1, the mass ratio of calcium carbonate in water to added fluorgypsum is (20-150):(850-980).

[0029] In any embodiment, in step S2, the mass ratio of added calcium salt of organic acid to fluorgypsum is (1-3):(850-980).

[0030] In any embodiment, in step S3, the fineness of added calcium hydroxide is 325-800 mesh.

[0031] In any embodiment, after step S3, the processed fluorgypsum is further dried at 120-160℃ for 15-30 minutes.

[0032] The dried safe fluorgypsum powder has a pH value of 7-8, about 90% of anhydrous calcium sulfate and about 10% of hemihydrated calcium sulfate, and has a certain cementation effect.

[0033] Compared with the prior art, the present application has the following advantages: the method for processing safe fluorogypsum powder provided by the present application comprises the following steps: S1, adding fluorogypsum into water containing calcium carbonate and stirring; S2, then adding organic acid calcium salt and continuing to stir; S3, then adding calcium hydroxide and continuing to stir to obtain processed fluorogypsum. The acid-containing substance in the gypsum is rapidly released and reacts with the calcium carbonate in the water to produce a large amount of CO2 gas, the CO2 gas rises to generate an air current, which can push and entrain impurities, oil stains, heavy metals and flotation agents to float to the surface of the slurry; the stirring tank float rod is started to collect the organic waste residues and the like on the surface of the slurry, which is discharged through the residue suction port, and the collected organic waste residues can be used as fertilizer; the further added organic acid calcium salt can fix the free fluorine in the fluorogypsum body, and the continued addition of calcium hydroxide can further fix the heavy metal impurities in the fluorogypsum to obtain a safe fluorogypsum body; after the processing of the safe fluorogypsum, the product phase becomes pure, the pores in the body are uniform, the attached water is easy to remove, and the drying time is shortened; during the drying and crushing process, the excess calcium hydroxide is carbonized into calcium carbonate, so that the pH value of the safe fluorogypsum powder is reduced to neutral. The method provided by the present application can efficiently remove the residual acid, residual fluorine and heavy metal impurities in the fluorogypsum, has high processing efficiency, and the reaction process can be completed within 1 hour. BRIEF DESCRIPTION OF DRAWINGS

[0034] Fig. 1 is a photo of the preparation of the safe fluorogypsum body in Example 1 of the present application.

[0035] Fig. 2 is the dry and crisp porous structure of the safe fluorogypsum body after processing in Example 1 of the present application.

[0036] Fig. 3 is the XRD pattern of the safe fluorogypsum after processing in Example 1 of the present application. DETAILED DESCRIPTION

[0037] "ranges" disclosed herein are defined, stated, or indicated to consist of at least the property, value, limitation or component "a" to "b" or, alternatively, "a" to "b", where "a" and "b" are endpoints of a range and include the individual values within the range. Such ranges are inclusive of the endpoints. Unless specifically stated otherwise, the use of "or" in the description refers to the nonexclusive included potential of a property, value, limitation, or component, etc. described using "or". For example, a composition, product, or method that "includes" or "comprises" a list of features is not limited only to those features but also to equivalent features that do not expressly appear in the list. For example, if a composition, product, or method includes components A, B, or C, it also includes A, B, and C, A and B, A and C, B and C, or A, B, and C. Likewise, if a composition, product, or method includes features X, Y, or Z, it also includes X, Y, and Z, X and Y, X and Z, Y and Z, or X, Y, and Z.

[0038] The terms "comprise" (and any grammatical variations thereof, such as "comprises" and "comprising"), "contain" (and any grammatical variations thereof, such as "contains" and "containing"), "include" (and any grammatical variations thereof, such as "includes" and "including") and "have" (and any grammatical variations thereof, such as "has" and "having") are open-ended, both in the

[0039] The term "or" as used in the specification and in claims includes both "and" and "or" unless otherwise indicated. For example, a condition "A or B" is satisfied by either A or B or both A and B. In other words, when discussing two or more items "A or B" covers all of the following instances: A is true (or present) and B is false (or not present); A is false (or not present) and B is true (or present); and both A and B are true (or present).

[0040] The embodiment provides a treatment method of safe fluorogypsum powder, comprising the following steps: S1, adding fluorogypsum to water containing calcium carbonate, stirring for 10 min to 20 min, the stirring speed is 10 r / min to 30 r / min; the fineness of calcium carbonate added in the water containing calcium carbonate is 325 mesh to 800 mesh; the mass ratio of calcium carbonate in water to added fluorogypsum is (20-150):(850-980); the water containing calcium carbonate is obtained by feeding calcium carbonate into water for 10 s to 20 s; S2, then add calcium salt of organic acid and continue stirring for 2-3 minutes, the stirring speed is 50-100 r / min, the calcium salt of organic acid is one or more of calcium formate, calcium acetate, calcium propionate and calcium ascorbate, the mass ratio of the added calcium salt of organic acid to fluorogypsum is (1-3):(850-980); S3, then add calcium hydroxide with fineness of 325-800 meshes and continue stirring for 2-3 minutes, the pH value of the slurry is adjusted to 10-12, the stirring speed is 50-100 r / min, and the treated fluorogypsum is obtained, and the treated fluorogypsum is dried at 120-160 DEG C for 15-30 minutes.

[0041] The beneficial effects of the present application also include: 1) removing the irritating odor of building fluorogypsum powder.

[0042] 2) removing the acidic substances such as residual hydrogen fluoride, sulfuric acid, heteroacid and by-product of the secondary reaction in the building fluorogypsum, and removing the fluorine ions.

[0043] 3) reducing the content of other heavy metal elements in the building fluorogypsum.

[0044] 4) the process time can be shortened to 1 hour from the output of acidic fluorogypsum to the preparation of building fluorogypsum powder, and the time for preparing safe fluorogypsum slurry is only 30 minutes. The production cycle of building fluorogypsum powder can be shortened, the energy consumption can be reduced, and thus the cost can be reduced.

[0045] In order to make the purpose, technical scheme and advantages of the present application clearer and more apparent, the present application will be further described in detail below in combination with the drawings and examples. It should be understood that the specific examples described herein are only used to explain the present application, and are not used to limit the present application.

[0046] In the present application, "some embodiments", "the present embodiment" and examples and the like are described, which describe a subset of all possible embodiments, but it can be understood that "some embodiments" can be the same subset or different subset of all possible embodiments, and can be combined with each other without conflict.

[0047] If similar descriptions of "first / second" appear in the application file, the following description is added, in the following description, the terms "first\second\third" are only used to distinguish similar objects, and do not represent the specific order of the objects, and it can be understood that "first\second\third" can be interchanged in the specific order or sequence as allowed, so that the embodiments described herein can be implemented in an order other than that illustrated or described herein.

[0048] The term "and / or" in the present embodiment only describes the association relationship of the associated objects, and indicates that there can be three relationships, for example, object A and / or object B, which can represent three cases of the existence of object A alone, the existence of object A and object B together, and the existence of object B alone.

[0049] Hereinafter, the embodiments of the present application will be described. The embodiments described below are exemplary and are only used to explain the present application, and cannot be understood as a limitation of the present application. If the specific technology or condition is not indicated in the embodiments, the technology or condition described in the literature in the art or according to the product manual is used. If the manufacturer of the reagent or instrument is not indicated, it is a conventional product that can be obtained by purchase.

[0050] Embodiment 1 The present embodiment proposes a treatment method of safe fluorogypsum powder, which comprises the following steps: 1) 250 kg of water is first put into the anticorrosive stirring tank, 23.125 kg of calcium carbonate powder with fineness of 325 mesh to 800 mesh is put in, and polytetrafluoroethylene stirring blade is used to stir at a stirring speed of 20 r / min for 15 s.

[0051] 2) 975 kg of cooled acid fluorogypsum is slowly put into the stirring tank, and stirring is carried out at a stirring speed of 25 r / min, the whole feeding and stirring process is about 15 min, and the feeding amount is ensured to be able to stir the fluorogypsum, which is generally in paste or milk shape, and the water content is below 25%. When the fluorogypsum is put into water, the acid-containing substances in the fluorogypsum are rapidly released and combined with the calcium carbonate in the water to produce a large amount of CO2 gas. The CO2 gas rises to produce air flow, which pushes and entrains impurities, oil stains and organic matters such as flotation agent to the surface of the slurry. The floating rod of the stirring tank is started to collect the organic matter waste and the like on the surface of the slurry, which is discharged through the sludge suction port. The collected organic matter waste can be used as fertilizer.

[0052] 3) After the fluorogypsum is put in, 1.25 kg of calcium formate powder is continuously added, and the slurry is stirred at 80 r / min for 2 min, which is used to fix the free fluorine in the fluorogypsum paste.

[0053] 4) According to the actual slurry pH value, calcium hydroxide (pure lime powder) with fineness of 325 mesh to 800 mesh is added to adjust the slurry pH value to 11, and stirring is carried out at 80 r / min for 2 min, which is used to fix the heavy metals in the fluorogypsum, to obtain safe fluorogypsum paste.

[0054] 5) The safe fluorogypsum paste is quickly dried at 140℃ for 25 min, until there is no attached water in the safe fluorogypsum, and all the dihydrate gypsum is converted into β hemihydrate gypsum. Because there are a large number of pores in the fluorogypsum paste, the material can be quickly dehydrated.

[0055] 6) The dried material is very crisp and easy to break. It can be directly ground to 400-800 mesh by ball mill or Raymond mill to obtain safe fluorogypsum powder.

[0056] Combining Figs. 1-3 It can be seen that the treated gypsum in Example 1 is mainly anhydrite, and the dried safe fluorogypsum body is crisp and porous.

[0057] Example 2 The present embodiment proposes a treatment method of safe fluorogypsum powder, comprising the following steps: 1) 250 kg of water is first added to the corrosion-resistant stirring tank, and 23.125 kg of calcium carbonate powder with fineness of 325-800 mesh is added. The stirring speed is 30 r / min, and the stirring time is 10 s.

[0058] 2) Slowly add 975 kg of cooled acid fluorogypsum into the stirring tank, and stir at a stirring speed of 10 r / min. The whole feeding and stirring process takes about 20 min. The feeding amount is ensured to be able to stir the fluorogypsum, which is generally in paste or milk form, and the water content is below 25%. When the fluorogypsum is added into water, the acid-containing substances in the fluorogypsum are rapidly released and react with the calcium carbonate in the water to produce a large amount of CO2 gas. The CO2 gas rises to generate air flow, which pushes and entrains impurities, oil stains and organic matters such as flotation agents to the surface of the slurry. The floating rod of the stirring tank is started to collect the organic matter waste and other residues on the surface of the slurry, which are discharged through the residue suction port. The collected organic matter waste can be used as fertilizer.

[0059] 3) After the fluorogypsum is added, 1.25 kg of calcium acetate powder is continuously added, and the slurry is stirred at a speed of 50 r / min for 3 min to fix the free fluorine in the fluorogypsum body.

[0060] 4) According to the actual pH value of the slurry, add calcium hydroxide (pure lime powder) with fineness of 325-800 mesh to adjust the pH value of the slurry to 11, and stir at a speed of 50 r / min for 3 min to fix the heavy metals in the fluorogypsum, thereby obtaining a safe fluorogypsum body.

[0061] 5) The safe fluorogypsum body is quickly dried at 120°C for 30 min. The safe fluorogypsum is dried without attached water, and all the dihydrate gypsum is converted into β hemihydrate gypsum. Due to the existence of a large number of pores in the fluorogypsum body, the material can be quickly dehydrated.

[0062] 6) The dried material is very crisp and easy to break. It can be directly ground to 400-800 mesh by ball mill or Raymond mill to obtain safe fluorogypsum powder.

[0063] Example 3 The present embodiment proposes a treatment method of safe fluorogypsum powder, comprising the following steps: 1) Put 250 kg water into the anti-corrosion mixing tank first, and then put 23.125 kg calcium carbonate powder with a fineness of 325-800 meshes into the tank, and use the polytetrafluoroethylene stirring blade to stir at a stirring speed of 30 r / min for 10 s.

[0064] 2) Slowly put the cooled 975 kg acid fluorogypsum into the mixing tank while stirring at a stirring speed of 30 r / min, and the whole feeding and stirring process takes about 10 min. The feeding amount is ensured to be able to stir the fluorogypsum open, generally in a paste or milk shape, and the water content is below 25%. When the fluorogypsum is put into water, the acid-containing substances in the fluorogypsum are rapidly released and combined with the calcium carbonate in the water to produce a large amount of CO2 gas. The CO2 gas rises to generate an air current, which pushes and entrains impurities, oil stains and organic matters such as flotation agents to the surface of the slurry. The floating rod of the mixing tank is started to collect the organic matter waste and the like on the surface of the slurry and discharge them through the sludge suction port. The collected organic matter waste can be used as fertilizer.

[0065] 3) After the fluorogypsum is put in, continue to add 1.25 kg of calcium propionate powder, and stir the slurry at 100 r / min for 2 min to fix the free fluorine in the fluorogypsum paste.

[0066] 4) According to the actual pH value of the slurry, add calcium hydroxide (pure lime powder) with a fineness of 325-800 meshes to adjust the pH value of the slurry to 12, and stir at 100 r / min for 2 min to fix the heavy metals in the fluorogypsum, so as to obtain safe fluorogypsum paste.

[0067] 5) The safe fluorogypsum paste is quickly dried at 160℃ for 15 min until there is no attached water in the safe fluorogypsum, and all the dihydrate gypsum is converted into β hemihydrate gypsum. Since there are a large number of pores in the fluorogypsum paste, the material can be quickly dehydrated.

[0068] 6) The dried material is very crisp and easy to break, and can be directly finely ground to 400-800 meshes by using a ball mill or a Raymond mill to obtain safe fluorogypsum fine powder.

[0069] The safe fluorogypsum fine powder obtained in Example 1 and the fluorogypsum raw powder before treatment are sent for detection, and the results are shown in Table 1.

[0070] Table 1 Detection data of fluorogypsum leaching solution after treatment of Example 1 and fluorogypsum leaching solution before treatment As can be seen from Table 1, the metal elements in the fluorogypsum treated by the treatment method of the present application are greatly reduced, and the fluoride is significantly reduced, which indicates that the metal elements are effectively removed and solidified, and the pH value of the leaching solution is 7, which indicates that it almost does not contain acid.

[0071] The present application uses a wet reaction, in a solution system, the residual acidic substances, soluble fluorine and heavy metals in the fluorogypsum are rapidly released.

[0072] It should be noted that the treatment method of examples 2-3 obtains the effect of fluorogypsum equivalent to example 1.

[0073] The key point 1 of the present application: first, calcium carbonate reacts with acidic fluorogypsum, calcium carbonate and acidic substances in acidic fluorogypsum produce a metathesis reaction, rapidly consume hydrogen ions, and raise the pH value from 1-2 to 5-6; at the same time, the generated CO2 gas has a flotation effect in the fluorogypsum slurry, impurities, oil stains, flotation agents, heavy metals and other impurities in the fluorogypsum are wrapped together with the CO2 gas, and are collected and cleaned by the float rod, which greatly removes impurities and increases whiteness.

[0074] The key point 2 of the present application: using calcium formate, calcium acetate, calcium propionate or calcium ascorbate to fix fluorine ions in the system to generate CaF2 and other insoluble substances to fix free fluorine. The fluorogypsum becomes a truly safe and environmentally friendly building gypsum powder.

[0075] The key point 3 of the present application: using calcium hydroxide instead of calcium oxide can fix the residual heavy metals in fluorogypsum, and can also raise the pH value of the gypsum slurry to 10-12 to prevent the presence of residual acid. Excess calcium hydroxide can be directly carbonized without affecting the stability of the subsequent building fluorogypsum powder.

[0076] The key point 4 of the present application: the conventional calcium oxide mixing method is a solid-solid reaction method, which generally requires more than 7 days for a cycle. Since the calcium fluoride and calcium sulfate in the product are insoluble or slightly soluble, an attached layer is easily generated, which has the risk of incomplete reaction. The present method uses a fluorogypsum water-dissolving wet reaction, which is a solid-liquid reaction method, and can obtain safe fluorogypsum powder within 1h, which is short in time and high in efficiency.

[0077] The specific embodiments of the present application described above do not constitute a limitation on the scope of protection of the present application. Any other corresponding changes and modifications made in accordance with the technical concept of the present application shall be included in the scope of protection of the claims of the present application.

Claims

1. A method for processing safe fluorogypsum powder, characterized in that, Includes the following steps: S1. Add fluorogypsum to water containing calcium carbonate and stir. S2, then add the organic acid calcium salt and continue stirring; S3. Then add calcium hydroxide and continue stirring to obtain the treated fluorogypsum.

2. The method for processing safe fluorogypsum powder according to claim 1, characterized in that, In step S2, the organic acid calcium salt is added and stirred for 2 to 3 minutes at a speed of 50 to 100 r / min; and / or, in step S1, fluorogypsum is added to water containing calcium carbonate and stirred for 10 to 20 minutes at a speed of 10 to 30 r / min.

3. The method for processing safe fluorogypsum powder according to claim 1, characterized in that, In step S3, calcium hydroxide is added and stirring is continued for 2 to 3 minutes at a speed of 50 to 100 r / min.

4. The method for processing safe fluorogypsum powder according to claim 1, characterized in that, In step S2, the organic acid calcium salt is one or more of calcium formate, calcium acetate, calcium propionate, and calcium ascorbate.

5. The method for processing safe fluorogypsum powder according to claim 1, characterized in that, In step S3, calcium hydroxide is added and stirring is continued to adjust the pH of the slurry to 10-12.

6. The method for treating safe fluorogypsum powder according to claim 1, characterized in that, In step S1, the calcium carbonate added to the water containing calcium carbonate has a fineness of 325 mesh to 800 mesh.

7. The method for processing safe fluorogypsum powder according to claim 1, characterized in that, In step S1, the mass ratio of calcium carbonate in water to added fluorogypsum is (20-150):(850-980).

8. The method for processing safe fluorogypsum powder according to claim 1, characterized in that, In step S2, the mass ratio of the added organic acid calcium salt to fluorogypsum is (1-3):(850-980).

9. The method for processing safe fluorogypsum powder according to claim 1, characterized in that, In step S3, the added calcium hydroxide has a fineness of 325 mesh to 800 mesh.

10. The method for processing safe fluorogypsum powder according to claim 1, characterized in that, After step S3, the process further includes drying the treated fluorogypsum at 120°C to 160°C for 15 min to 30 min.

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