Environment-friendly and safe barite impurity removal acid boiling process

Abstract

The invention discloses an environment-friendly and safe barite impurity removal acid boiling technology, and belongs to the technical field of barite impurity removal, and the technology comprises the following steps: 1, barite raw material pretreatment: barite grinding and crushing, microwave treatment, low-temperature freezing and salt washing treatment; 2, spraying an environment-friendly anti-corrosion coating on the inner surface of the acid cooking pool; 3, the pretreated barite raw materials are added into an acid cooking pool in two layers, after the lower-layer barite raw materials are added, the lower-layer barite raw materials are evenly poured with sulfuric acid, then the upper-layer barite raw materials are added, and then the surface layers of the upper-layer barite raw materials are evenly poured with sulfuric acid; 4, after barite enters the pool, the opening of the acid cooking pool is covered with a polyethylene film; step five, performing acid cooking for 5-6h; and 6, filtering, deacidifying, washing and drying the acid-boiled material to obtain the purified barite. By optimizing the acid boiling process, the purity of the purified barite is higher than 98%.

Description

Technical Field

[0001] This invention relates to the field of barite impurity removal technology, specifically to an environmentally friendly and safe acid boiling process for barite impurity removal. Background Technology

[0002] Barite, composed of barium sulfate (BaSO4), is widely used in petroleum, chemical, paint, and filler industries. Natural barite often contains many impurities, such as quartz, calcite, dolomite, clay minerals, and iron oxide, thus requiring purification to remove these impurities.

[0003] The acid boiling process for removing impurities from barite involves reacting acid with impurities (such as carbonates, metal oxides, and silicates) to dissolve or convert them into separable substances, thereby increasing the purity of barite.

[0004] However, the following technical drawbacks still exist: First, high-concentration acid solutions (such as 98% sulfuric acid) have high reaction efficiency, but they are also highly corrosive to the acid boiling tank, so the acid boiling tank needs to be frequently treated for corrosion resistance; second, the purity of barite still needs to be further improved, so the acid boiling process needs to be optimized.

[0005] Based on this, the present invention designs an environmentally friendly and safe acid boiling process for removing impurities from barite to solve the above problems. Summary of the Invention

[0006] In view of the above-mentioned shortcomings of the existing technology, the present invention provides an environmentally friendly and safe acid boiling process for removing impurities from barite.

[0007] To achieve the above objectives, the present invention provides the following technical solution: An environmentally friendly and safe acid leaching process for removing impurities from barite includes the following steps: Step 1: Pretreatment of barite raw materials, including grinding and crushing, microwave treatment, low-temperature freezing and salt washing of barite; Step 2: Spray an environmentally friendly anti-corrosion coating on the inner surface of the acid boiling tank. The environmentally friendly anti-corrosion coating is prepared from the following raw materials in parts by weight: 60-70% phenolic epoxy resin, 6-10% glass flakes, 3-isocyanate-propyltriethoxysilane-modified graphene oxide, 6-10% nano-grade barium sulfate, and the balance is an additive (curing agent). Step 3: Add the pretreated barite raw material in two layers in the acid boiling tank. After adding the lower layer of barite raw material, first pour 10% sulfuric acid evenly over the lower layer of barite raw material, then add the upper layer of barite raw material, and then pour 10% sulfuric acid evenly over the surface of the upper layer of barite raw material for natural penetration. Step 4: After completing the process of adding barite to the tank, cover the opening of the acid boiling tank with polyethylene film to seal its surroundings. Step 5: Turn on the steam generator and acid mist absorption tower. The steam generator produces steam, which indirectly heats the sulfuric acid in the acid boiling tank, raising the reaction temperature to 90~100℃ and accelerating the removal of impurities. The acid boiling process lasts for 5~6 hours. The generated acid vapor enters the acid mist absorption tower through the top pipe of the acid boiling tank. After filtration, recovery, and concentration, the acid vapor is used to obtain sulfuric acid. Step 6: After acid cooking, the material is filtered to remove acid, washed, and dried to obtain purified barite; the resulting wastewater flows into an acid-base neutralization tank, where caustic soda is added to react until the pH reaches 7, and after passing the test, it is discharged into an industrial water storage tank.

[0008] Furthermore, in step one, barite is ground and crushed to pass through a sieve of 200-300 mesh to obtain barite powder.

[0009] Furthermore, in step one, the microwave treatment process is as follows: the barite powder is first treated under microwave conditions with a power of 650~800W for 5~12 minutes, and then treated under microwave conditions with a power of 800~950W for 1.5~3 minutes.

[0010] Furthermore, in step one, the low-temperature freezing process is as follows: after cooling the microwave-treated barite powder to 30~40℃, it is placed in an environment of 0~-15℃ for freezing treatment for 30~50 minutes, and then taken out and restored to room temperature.

[0011] Furthermore, in step one, the salt washing method is as follows: barite powder is placed in an 8-11 wt% NaCl solution, ultrasonically assisted treatment is performed at room temperature for 3-5 minutes, filtered, washed, and dried at a low temperature of 60-70℃. The salt washing wastewater is neutralized, heavy metal ion precipitation is performed, filtered, evaporated and concentrated, and NaCl is recovered by crystallization.

[0012] Furthermore, in step two, the dry film thickness of the environmentally friendly anti-corrosion coating is 100~120 μm.

[0013] Furthermore, in step two, the preparation method of 3-isocyanate-propyltriethoxysilane-modified graphene oxide is as follows: 10g of graphene oxide is dispersed in 1L of N-methylpyrrolidone, and then 25~30g of 3-isocyanate-propyltriethoxysilane is slowly added. The mixture is stirred and reacted at 55~58℃ for 2~5h. After centrifugation, washing, and drying, the graphene oxide is obtained.

[0014] Furthermore, in step two, the preparation method of the environmentally friendly anti-corrosion coating is as follows: weigh phenolic epoxy resin, add an appropriate amount of solvent to dissolve it, and then add additives, glass flakes, nano-sized barium sulfate and 3-isocyanate-based propyltriethoxysilane-modified graphene oxide in sequence, and ultrasonically stir evenly to obtain the environmentally friendly anti-corrosion coating.

[0015] Furthermore, in step three, the thickness ratio of the lower layer of barite raw material to the upper layer of barite raw material is controlled at 4~5:2~3.

[0016] Furthermore, in step three, after adding the lower layer of barite raw material, 10% sulfuric acid is added for the first time, and the 10% sulfuric acid is used to evenly pour onto the lower layer of barite raw material. The amount of sulfuric acid added is sufficient to completely impregnate the lower layer of barite raw material. After adding the upper layer of barite raw material, 10% sulfuric acid is added for the second time, and the 10% sulfuric acid is used to evenly pour onto the surface of the upper layer of barite raw material. The mass of the sulfuric acid added for the second time is 0.4 to 0.6 times the mass of the sulfuric acid added for the first time.

[0017] Compared with existing technologies, the advantages of this invention are as follows: By optimizing the acid boiling process, the purity of the purified barite exceeds 98%. This invention significantly reduces the sulfuric acid concentration and reduces the corrosiveness of subsequent concentrated acid additions by spraying an environmentally friendly anti-corrosion coating onto the inner surface (metal material) of the acid boiling tank. The coating's resistance to acid (10% sulfuric acid, 100℃) immersion (GB / T 30648.1-2014) was tested, and no serious corrosion, rust, blistering, or cracking was observed after immersion for 240 hours. Detailed Implementation

[0018] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0019] Example 1: An environmentally friendly and safe acid leaching process for removing impurities from barite, comprising the following steps: Step 1: Pretreatment of barite raw materials, including grinding and crushing, microwave treatment, low-temperature freezing and salt washing of barite; In this process, barite is ground and crushed to pass through a 200-mesh sieve to obtain barite powder; The microwave processing procedure is as follows: barite powder is first treated under microwave conditions with a power of 650W for 12 minutes, and then treated under microwave conditions with a power of 800W for 3 minutes. The low-temperature freezing process is as follows: after the barite powder is microwave-treated, it is cooled to 30°C and then placed in an environment of -15°C for freezing treatment for 30 minutes. After being taken out, it is restored to room temperature. The salt washing method is as follows: barite powder is placed in an 8wt% NaCl solution and ultrasonically treated for 5 minutes at room temperature. After filtration, it is washed and dried at a low temperature of 60℃. The salt washing wastewater is neutralized, heavy metal ion precipitation is carried out, filtered, evaporated and concentrated, and NaCl is recovered by crystallization. The mother liquor is recycled to reduce raw material waste and environmental pollution.

[0020] Step 2: Spray an environmentally friendly anti-corrosion coating onto the inner surface of the acid boiling tank. This coating is prepared from the following raw materials in parts by weight: 60% phenolic epoxy resin, 10% glass flakes, 3% 3-isocyanate-propyltriethoxysilane-modified graphene oxide, 6% nano-sized barium sulfate, with the remainder being additives (curing agent). Weigh the phenolic epoxy resin, dissolve it in an appropriate amount of solvent, then sequentially add the additives, glass flakes, nano-sized barium sulfate, and 3-isocyanate-propyltriethoxysilane-modified graphene oxide. Stir ultrasonically until homogeneous to obtain the environmentally friendly anti-corrosion coating. The thickness of the environmentally friendly anti-corrosion coating is 100 μm (dry film). The preparation method of 3-isocyanate-propyltriethoxysilane modified graphene oxide is as follows: 10g of graphene oxide is dispersed in 1L of N-methylpyrrolidone, and then 25g of 3-isocyanate-propyltriethoxysilane is slowly added. The mixture is stirred and reacted at 58℃ for 2h. After centrifugation, washing and drying, the graphene oxide is obtained. Step 3: Add the pretreated barite raw material in two layers in the acid boiling tank. After adding the lower layer of barite raw material, first pour 10% sulfuric acid evenly over the lower layer of barite raw material, then add the upper layer of barite raw material, and then pour 10% sulfuric acid evenly over the surface of the upper layer of barite raw material for natural penetration. The thickness ratio of the lower barite material to the upper barite material is controlled at 2:1. After adding the lower barite material, 10% sulfuric acid is added for the first time, and the 10% sulfuric acid is used to evenly pour the lower barite material. The amount of sulfuric acid added is sufficient to completely impregnate the lower barite material. After adding the upper barite material, 10% sulfuric acid is added for the second time, and the 10% sulfuric acid is used to evenly pour the surface of the upper barite material. The mass of the second added sulfuric acid is 0.6 times the mass of the first added sulfuric acid.

[0021] Step 4: After completing the process of adding barite to the tank, cover the opening of the acid boiling tank with polyethylene film to seal its surroundings and prevent acid vapor from leaking out. Step 5: Turn on the steam generator and acid mist absorption tower. The steam generator produces steam, which indirectly heats the sulfuric acid in the acid boiling tank, raising the reaction temperature to 100°C and accelerating the removal of impurities. The acid boiling process lasts for 5 hours. The generated acid vapor enters the acid mist absorption tower through the top pipe of the acid boiling tank. After filtration, recovery, and concentration, the acid vapor is used to obtain sulfuric acid, achieving recycling. Step 6: After acid cooking, the material is filtered to remove acid, washed, and dried to obtain purified barite; the resulting wastewater flows into an acid-base neutralization tank, where caustic soda is added to react until the pH reaches 7, and after passing the test, it is discharged into an industrial water storage tank.

[0022] The purity of barite was tested to be 98.6%.

[0023] Example 2: An environmentally friendly and safe acid leaching process for removing impurities from barite, comprising the following steps: Step 1: Pretreatment of barite raw materials, including grinding and crushing, microwave treatment, low-temperature freezing and salt washing of barite; In this process, barite is ground and crushed to pass through a 300-mesh sieve to obtain barite powder; The microwave processing procedure is as follows: barite powder is first treated under microwave conditions with a power of 800W for 5 minutes, and then treated under microwave conditions with a power of 950W for 1.5 minutes. The low-temperature freezing process is as follows: after the barite powder is cooled to 40°C after microwave treatment, it is placed in an environment of 0°C for freezing treatment for 50 minutes, and then taken out and restored to room temperature. The salt washing method is as follows: barite powder is placed in an 11wt% NaCl solution and ultrasonically assisted for 3 minutes at room temperature. After filtration, it is washed and dried at a low temperature of 70℃. The salt washing wastewater is neutralized, heavy metal ion precipitation is carried out, filtered, evaporated and concentrated, and NaCl is recovered by crystallization. The mother liquor is recycled to reduce raw material waste and environmental pollution.

[0024] Step 2: Spray an environmentally friendly anti-corrosion coating onto the inner surface of the acid boiling tank. This coating is prepared from the following raw materials in parts by weight: 70% phenolic epoxy resin, 6% glass flakes, 3.5% 3-isocyanate-propyltriethoxysilane-modified graphene oxide, 10% nano-sized barium sulfate, with the remainder being additives (curing agent). Weigh the phenolic epoxy resin, dissolve it in an appropriate amount of solvent, and then sequentially add the additives, glass flakes, nano-sized barium sulfate, and 3-isocyanate-propyltriethoxysilane-modified graphene oxide. Stir ultrasonically until homogeneous to obtain the environmentally friendly anti-corrosion coating. The thickness of the environmentally friendly anti-corrosion coating is 120 μm (dry film). The preparation method of 3-isocyanate-propyltriethoxysilane modified graphene oxide is as follows: 10g of graphene oxide is dispersed in 1L of N-methylpyrrolidone, and then 30g of 3-isocyanate-propyltriethoxysilane is slowly added. The mixture is stirred and reacted at 55℃ for 5h. After centrifugation, washing and drying, the graphene oxide is obtained. Step 3: Add the pretreated barite raw material in two layers in the acid boiling tank. After adding the lower layer of barite raw material, first pour 10% sulfuric acid evenly over the lower layer of barite raw material, then add the upper layer of barite raw material, and then pour 10% sulfuric acid evenly over the surface of the upper layer of barite raw material for natural penetration. The thickness ratio of the lower barite material to the upper barite material is controlled at 5:3. After adding the lower barite material, 10% sulfuric acid is added for the first time, and the 10% sulfuric acid is used to evenly pour the lower barite material. The amount of sulfuric acid added is sufficient to completely impregnate the lower barite material. After adding the upper barite material, 10% sulfuric acid is added for the second time, and the 10% sulfuric acid is used to evenly pour the surface of the upper barite material. The mass of the second added sulfuric acid is 0.5 times the mass of the first added sulfuric acid. Step 4: After completing the process of adding barite to the tank, cover the opening of the acid boiling tank with polyethylene film to seal its surroundings and prevent acid vapor from leaking out. Step 5: Turn on the steam generator and acid mist absorption tower. The steam generator produces steam, which indirectly heats the sulfuric acid in the acid boiling tank, raising the reaction temperature to 95°C and accelerating the removal of impurities. The acid boiling process lasts for 5.5 hours. The generated acid vapor enters the acid mist absorption tower through the top pipe of the acid boiling tank. After filtration, recovery, and concentration, the acid vapor is used to obtain sulfuric acid, achieving recycling. Step 6: After acid cooking, the material is filtered to remove acid, washed, and dried to obtain purified barite; the resulting wastewater flows into an acid-base neutralization tank, where caustic soda is added to react until the pH reaches 7, and after passing the test, it is discharged into an industrial water storage tank.

[0025] The purity of barite was tested to be 98.4%.

[0026] Example 3: An environmentally friendly and safe acid leaching process for removing impurities from barite, comprising the following steps: Step 1: Pretreatment of barite raw materials, including grinding and crushing, microwave treatment, low-temperature freezing and salt washing of barite; Among them, barite is ground and crushed to pass through a 250-mesh sieve to obtain barite powder; The microwave processing procedure is as follows: barite powder is first treated under a microwave condition with a power of 700W for 8 minutes, and then treated under a microwave condition with a power of 850W for 2 minutes. The low-temperature freezing process is as follows: after the barite powder is microwave-treated, it is cooled to 35°C and then placed in an environment of -5°C for freezing treatment for 45 minutes. After being taken out, it is restored to room temperature. The salt washing method is as follows: barite powder is placed in a 10wt% NaCl solution and ultrasonically assisted for 4 minutes at room temperature. After filtration, it is washed and dried at a low temperature of 65℃. The salt washing wastewater is neutralized, heavy metal ion precipitation is carried out, filtered, evaporated and concentrated, and NaCl is recovered by crystallization. The mother liquor is recycled to reduce raw material waste and environmental pollution.

[0027] Step 2: Spray an environmentally friendly anti-corrosion coating onto the inner surface of the acid boiling tank. This coating is prepared from the following raw materials in parts by weight: 68% phenolic epoxy resin, 9% glass flakes, 5% 3-isocyanate-propyltriethoxysilane-modified graphene oxide, and 8% nano-sized barium sulfate, with the remainder being additives (curing agent). Weigh the phenolic epoxy resin, dissolve it in an appropriate amount of solvent, and then sequentially add the additives, glass flakes, nano-sized barium sulfate, and 3-isocyanate-propyltriethoxysilane-modified graphene oxide. Stir the mixture ultrasonically until homogeneous to obtain the environmentally friendly anti-corrosion coating. The thickness of the environmentally friendly anti-corrosion coating is 110 μm (dry film). The preparation method of 3-isocyanate-propyltriethoxysilane modified graphene oxide is as follows: 10g of graphene oxide is dispersed in 1L of N-methylpyrrolidone, and then 28g of 3-isocyanate-propyltriethoxysilane is slowly added. The mixture is stirred and reacted at 57℃ for 3.5h. After centrifugation, washing and drying, the graphene oxide is obtained. Step 3: Add the pretreated barite raw material in two layers in the acid boiling tank. After adding the lower layer of barite raw material, first pour 10% sulfuric acid evenly over the lower layer of barite raw material, then add the upper layer of barite raw material, and then pour 10% sulfuric acid evenly over the surface of the upper layer of barite raw material for natural penetration. The thickness ratio of the lower layer barite material to the upper layer barite material is controlled at 2:1. After adding the lower layer barite material, 10% sulfuric acid is added for the first time, and the 10% sulfuric acid is used to evenly pour the lower layer barite material. The amount of sulfuric acid added is sufficient to completely impregnate the lower layer barite material. After adding the upper layer barite material, 10% sulfuric acid is added for the second time, and the 10% sulfuric acid is used to evenly pour the surface of the upper layer barite material. The mass of the second added sulfuric acid is 0.4 times the mass of the first added sulfuric acid. Step 4: After completing the process of adding barite to the tank, cover the opening of the acid boiling tank with polyethylene film to seal its surroundings and prevent acid vapor from leaking out. Step 5: Turn on the steam generator and acid mist absorption tower. The steam generator produces steam, which indirectly heats the sulfuric acid in the acid boiling tank, raising the reaction temperature to 90°C and accelerating the removal of impurities. The acid boiling process lasts for 6 hours. The generated acid vapor enters the acid mist absorption tower through the top pipe of the acid boiling tank. After filtration, recovery, and concentration, the acid vapor is used to obtain sulfuric acid, achieving recycling. Step 6: After acid cooking, the material is filtered to remove acid, washed, and dried to obtain purified barite; the resulting wastewater flows into an acid-base neutralization tank, where caustic soda is added to react until the pH reaches 7, and after passing the test, it is discharged into an industrial water storage tank.

[0028] The purity of the barite was tested to be 98.8%.

[0029] Comparative Example 1: The difference from Example 3 is that microwave treatment was omitted in step one. The purity of barite was measured to be 89.3%.

[0030] Comparative Example 2: The difference from Example 3 is that the cryogenic freezing treatment was missing in step one. The purity of barite was measured to be 86.5%.

[0031] Comparative Example 3: Unlike Example 3, this example lacks the microwave treatment and cryogenic freezing process in step one. The purity of the barite was determined to be 85.9%.

[0032] This invention optimizes the acid leaching process, resulting in a barite purity exceeding 98%.

[0033] This invention significantly reduces the concentration of sulfuric acid and reduces the corrosiveness of the subsequent addition of concentrated acid to the acid boiling tank by spraying an environmentally friendly anti-corrosion coating on the inner surface (metal material). The coating's resistance to acid (10% sulfuric acid, 100℃) immersion performance was tested (GB / T 30648.1-2014). After immersion for 240 hours, no serious corrosion, rust, blistering, or cracking was observed.

[0034] The process of this invention is relatively environmentally friendly and safe overall, and the purified barite has high purity. The barite raw material undergoes a pretreatment process involving grinding, crushing, microwave treatment, low-temperature freezing, and salt washing to purify the barite in one step. Then, the pretreated barite raw material is added in two layers to an acid boiling tank for a second purification. A polyethylene film is used to cover the opening of the acid boiling tank to prevent acid vapor leakage. A steam generator indirectly heats the sulfuric acid in the acid boiling tank with steam. The acid vapor generated during acid boiling enters an acid mist absorption tower through a top pipe in the tank. After filtration, recovery, and concentration, the acid vapor is used to obtain sulfuric acid for recycling. The resulting wastewater flows into an acid-base neutralization tank, where caustic soda is added and reacted before being discharged into an industrial water storage tank.

[0035] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions will not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. An environmentally friendly and safe acid leaching process for removing impurities from barite, characterized in that, Includes the following steps: Step 1: Pretreatment of barite raw materials, including grinding and crushing, microwave treatment, low-temperature freezing and salt washing of barite; Step 2: Spray an environmentally friendly anti-corrosion coating on the inner surface of the acid boiling tank. The environmentally friendly anti-corrosion coating is prepared from the following raw materials in parts by weight: 60-70% phenolic epoxy resin, 6-10% glass flakes, 3-5% 3-isocyanate-propyltriethoxysilane-modified graphene oxide, 6-10% nano-grade barium sulfate, and the remainder is additives. Step 3: Add the pretreated barite raw material in two layers in the acid boiling tank. After adding the lower layer of barite raw material, first use sulfuric acid to evenly pour sulfuric acid into the lower layer of barite raw material, then add the upper layer of barite raw material, and then use sulfuric acid to evenly pour sulfuric acid into the surface of the upper layer of barite raw material for natural penetration. Step 4: After completing the process of adding barite to the tank, cover the opening of the acid boiling tank with polyethylene film and seal its sides. Step 5: Turn on the steam generator and acid mist absorption tower. The steam generator produces steam, which indirectly heats the sulfuric acid in the acid boiling tank, raising the reaction temperature to 90~100℃ and accelerating the removal of impurities. The acid boiling process lasts for 5~6 hours. The generated acid vapor enters the acid mist absorption tower through the top pipe of the acid boiling tank. After filtration, recovery, and concentration, the acid vapor is used to obtain sulfuric acid. Step 6: After acid cooking, the material is filtered to remove acid, washed, and dried to obtain purified barite; the resulting wastewater flows into an acid-base neutralization tank, and after passing the test, it is discharged into an industrial water storage tank.

2. The environmentally friendly and safe acid leaching process for removing impurities from barite according to claim 1, characterized in that, In step one, barite is ground and crushed to pass through a sieve of 200-300 mesh to obtain barite powder.

3. The environmentally friendly and safe acid leaching process for removing impurities from barite according to claim 1, characterized in that, In step one, the microwave treatment process is as follows: the barite powder is first treated under microwave conditions with a power of 650~800W for 5~12 minutes, and then treated under microwave conditions with a power of 800~950W for 1.5~3 minutes.

4. The environmentally friendly and safe acid leaching process for removing impurities from barite according to claim 1, characterized in that, In step one, the low-temperature freezing process is as follows: after cooling the microwave-treated barite powder to 30~40℃, it is placed in an environment of 0~-15℃ for freezing treatment for 30~50 minutes, and then taken out and restored to room temperature.

5. The environmentally friendly and safe acid leaching process for removing impurities from barite according to claim 1, characterized in that, In step one, the salt washing method is as follows: barite powder is placed in an 8-11 wt% NaCl solution and ultrasonically assisted for 3-5 minutes at room temperature. After filtration, it is washed, dried at a low temperature of 60-70℃, and the salt washing wastewater is neutralized, heavy metal ion precipitated, filtered, evaporated and concentrated, and crystallized to recover NaCl.

6. The environmentally friendly and safe acid leaching process for removing impurities from barite according to claim 1, characterized in that, In step two, the dry film thickness of the environmentally friendly anti-corrosion coating is 100~120 μm.

7. The environmentally friendly and safe acid leaching process for removing impurities from barite according to claim 1, characterized in that, In step two, the preparation method of 3-isocyanate-propyltriethoxysilane-modified graphene oxide is as follows: 10g of graphene oxide is dispersed in 1L of N-methylpyrrolidone, and then 25~30g of 3-isocyanate-propyltriethoxysilane is slowly added. The mixture is stirred and reacted at 55~58℃ for 2~5h. After centrifugation, washing and drying, the graphene oxide is obtained.

8. The environmentally friendly and safe acid leaching process for removing impurities from barite according to claim 1, characterized in that, In step two, the preparation method of the environmentally friendly anti-corrosion coating is as follows: weigh phenolic epoxy resin, add an appropriate amount of solvent to dissolve it, and then add the additives, glass flakes, nano-sized barium sulfate and 3-isocyanate-based propyltriethoxysilane-modified graphene oxide in sequence, and stir evenly with ultrasonication to obtain the environmentally friendly anti-corrosion coating.

9. The environmentally friendly and safe acid leaching process for removing impurities from barite according to claim 1, characterized in that, In step three, the thickness ratio of the lower barite raw material to the upper barite raw material is controlled at 4~5:2~3.

10. The environmentally friendly and safe acid leaching process for removing impurities from barite according to claim 1, characterized in that, In step three, after adding the lower layer of barite raw material, 10% sulfuric acid is added for the first time. The 10% sulfuric acid is then used to evenly pour the lower layer of barite raw material, with the amount of sulfuric acid added being sufficient to completely impregnate the lower layer of barite raw material. After adding the upper layer of barite raw material, 10% sulfuric acid is added for the second time, and the 10% sulfuric acid is then used to evenly pour the surface of the upper layer of barite raw material. The mass of the sulfuric acid added the second time is 0.4 to 0.6 times the mass of the sulfuric acid added the first time.