Recycling treatment method for wastewater of uranium-molybdenum ore acid-method oxygen pressure leaching process

Abstract

The invention relates to the field of industrial wastewater treatment, in particular to a resource treatment method for wastewater of a uranium-molybdenum ore acid method oxygen pressure leaching process. The invention provides a uranium-molybdenum ore acid process oxygen pressure leaching process wastewater resourceful treatment method. The method comprises a manganese sand filter, a dosing stirring system 1, an asbestos plate frame filter, a dosing stirring system 2, a dosing stirring system 3, fluorine removal special resin, softening resin, a multi-section multi-stage RO system, an extraction system, an adsorption system and a multi-effect evaporator. According to the integrated process, turbidity, silicon and hardness in the process wastewater are removed synergistically, heavy metal ions are removed through a five-step method, finally, the process wastewater is recycled, the leaching rate of uranium and molybdenum is not affected, resource utilization of the process wastewater is achieved, consumption of natural water resources is reduced, and the water using cost can also be reduced.

Description

Technical Field

[0001] The invention relates to the field of industrial wastewater treatment, and in particular to a method for resource-based treatment of wastewater from an acid-based oxygen pressure leaching process of uranium-molybdenum ore. Background Art

[0002] With the accelerated development of industrialization and informatization, the demand for energy and chemical products in social production is also increasing, especially uranium used for nuclear fuel and nuclear industry development. Uranium is also used in nuclear science research and the development of new reactor technology. As a key metal in industry, molybdenum has a wide range of uses and importance in the steel industry, aerospace industry, electronics and electrical industry due to its excellent physical and chemical properties. The main source of uranium and molybdenum resources is still traditional land mining, and associated uranium-molybdenum ore is a typical uranium and molybdenum co-developed mineral. However, the mineral processing process is complicated, the extraction rate of target resources is not high, the demand for water is large, and the post-treatment of "industrial waste" and other problems have brought challenges to the maximum recovery rate of mineral development and resource utilization. In particular, the treatment of industrial wastewater generated after ore washing and separation, grinding and slurry mixing, and hydraulic transportation in the process has attracted great attention. On the one hand, process wastewater needs to consider its environmental issues. Wastewater contains a variety of ions. If it is not effectively treated, it will pose a serious threat to the ecological environment and human health. On the other hand, considering the economic benefits, the treated water can be reused in the production process, reducing the consumption of natural water resources and the cost of water use. Therefore, in the process of uranium and molybdenum mineral processing, how to achieve zero discharge of wastewater treatment and realize the recycling of water in the production line is a key issue in the mineral mining industry, and it is also a research demand and research goal in the chemical and material fields.

[0003] The current process wastewater reuse has the following problems:

[0004] Question 1: The process water is circulated in a closed-loop system for many times. The soluble impurity ions in the wastewater accumulate continuously during the circulation process, which has a serious impact on the leaching rate of molybdenum by oxygen pressure acid leaching.

[0005] The process water is circulated in the closed-loop system for many times, resulting in a gradual increase in the ion concentration in the wastewater. + 、Na + NH4 +The accumulation of molybdenum leads to a significant decrease in the leaching rate of molybdenum, which usually decreases by 6%-8%. On the one hand, monovalent cations usually have a high solubility, and their interaction with common precipitants is weak, and they will not easily form insoluble compounds like multivalent cations. Moreover, monovalent cations usually have a weak adsorption capacity on the surface of adsorption materials, and are difficult to effectively remove by adsorption. Many commonly used adsorption materials (such as activated carbon, zeolite, etc.) have poor adsorption capacity for monovalent cations. Therefore, they are difficult to remove from wastewater by simple physical methods (such as precipitation or filtration) and adsorption. On the other hand, there are often multiple ions in wastewater with high ionic strength, and there will be a competitive effect between monovalent cations and other multivalent cations or cations, resulting in reduced removal efficiency. Therefore, the reuse of process water seriously affects the leaching rate of molybdenum.

[0006] Question 2: Process water cannot be discharged directly.

[0007] Process wastewater contains a variety of heavy metal ions, which will pose a serious threat to the ecological environment and human health if not effectively treated. Therefore, process wastewater cannot be discharged directly.

[0008] Process wastewater can neither be recycled nor discharged directly. How to make resource utilization of process wastewater is a technical challenge.

[0009] The existing technology has the following technical difficulties in comprehensively solving the above problems:

[0010] Technical Difficulty 1: Impact of high salinity on reverse osmosis.

[0011] First, high salinity will increase the osmotic pressure, causing the reverse osmosis operating pressure to be too high, resulting in high operating costs and affecting the service life of the reverse osmosis membrane; second, high salinity will cause the reverse osmosis system to produce water with a high salt content, which cannot achieve the purpose of high desalination; third, various metal ions affect each other and interfere with the desalination rate of the reverse osmosis membrane; finally, various metal ions will produce precipitation with anions during reverse osmosis concentration, causing reverse osmosis blockage and, in severe cases, the reverse osmosis membrane to be scrapped.

[0012] Technical difficulty 2: The impact of high turbidity on reverse osmosis.

[0013] The process wastewater contains silica gel and other ingredients, which leads to high turbidity of the water. The reverse osmosis membrane requires the inlet turbidity to be less than 1NTU. If the turbidity exceeds this value, it will cause pollution and blockage of the reverse osmosis, causing the reverse osmosis membrane to be unable to operate normally, seriously affecting the service life of the reverse osmosis membrane.

[0014] Technical difficulty 3: The impact of high hardness on reverse osmosis.

[0015] High hardness water will have a serious impact on the reverse osmosis system, mainly manifested in the formation of scale on the membrane surface by hardness ions such as calcium and magnesium, leading to membrane blockage, decreased water permeability and reduced desalination efficiency. This not only increases the operating pressure and energy consumption of the system, but also shortens the service life of the membrane, resulting in increased maintenance costs.

[0016] Technical difficulty 4: The various components in the wastewater influence and interfere with each other, making it difficult to treat them as resources.

[0017] High turbidity affects the removal of other components; the various heavy metal ions contained in the wastewater affect the removal of calcium and magnesium ions; calcium and magnesium ions affect the removal of other heavy metal ions; multiple ions lead to high salt content, which makes the treatment process complicated. It is not possible to achieve water reuse by simply adding reverse osmosis and multi-effect evaporation. It is difficult to fully reduce the ion strength in process wastewater by using technologies other than reverse osmosis. Process wastewater treatment needs to be strictly controlled to avoid the impact of the previous treatment process on the subsequent treatment process. Summary of the invention

[0018] In view of the above technical problems and their technical difficulties, the following technical ideas are proposed (see Figure 1 ):

[0019] Regarding technical difficulty 1: it is necessary to use different processes in steps to remove metal ions: first, remove high turbidity substances such as silicon by adding magnesium ions; second, use the double alkali method to remove metal ions such as calcium, magnesium and iron; finally, further remove metal ions such as calcium and magnesium through softening resin, and then use fluororesin to remove fluoride ions in the water.

[0020] Technical Difficulty 2: Sand filtration, precision security filter and drug-added flocculation and sedimentation process are combined to reduce the turbidity of wastewater to below 1NTU to meet the water inlet requirements of reverse osmosis membrane. Large suspended solids and impurities in wastewater are removed by sand filtration, and then further filtered using precision security filters to ensure that the turbidity of inlet water reaches below 1NTU. Combined with the drug-added flocculation and sedimentation process, the tiny particles in the water are aggregated into larger precipitates by adding flocculants, which is convenient for subsequent filtration and treatment. This process can significantly reduce the turbidity of water and meet the water inlet standards of the reverse osmosis system. Finally, since the presence of silicon will form silicon scale on the surface of the reverse osmosis membrane, which seriously affects the performance and life of the membrane, it is necessary to specifically remove silicon from the water during turbidity control. By adding magnesium sulfate and using sodium hydroxide to adjust the pH of the solution, silicon is separated from the wastewater in the form of precipitation, further protecting the reverse osmosis membrane.

[0021] Technical Difficulty 3: The double alkali method combined with softening resin reduces the concentration of calcium and magnesium ions in the wastewater and increases the concentration multiple of the reverse osmosis membrane. The double alkali method (such as using sodium carbonate and sodium hydroxide) is used to adjust the alkalinity of the wastewater so that the calcium and magnesium ions react with the alkali to form insoluble precipitates (such as calcium carbonate and magnesium hydroxide), thereby reducing the concentration of calcium and magnesium ions in the water. After the double alkali method, the wastewater is further removed by softening resin to remove residual calcium and magnesium ions. This method can effectively increase the concentration multiple of the reverse osmosis membrane, avoid membrane scaling problems, extend the service life of the membrane and improve the overall treatment efficiency.

[0022] Regarding technical difficulty 4: First, use a manganese sand filter to remove turbidity and a portion of various heavy metal ions; then, add magnesium sulfate and combine with asbestos plate and frame filter to remove silicon and a portion of heavy metal ions; again, add sodium carbonate, adjust the pH with sodium hydroxide, and use amidoxime-modified polyacrylonitrile hollow fiber membrane to remove calcium and magnesium ions and a portion of heavy metal ions after uranium extraction from seawater; again, add sulfuric acid to adjust the pH and remove carbonate; again, enter the special fluorine removal resin to remove fluoride ions; again, enter the softening resin to further remove calcium and magnesium ions and a portion of heavy metal ions; again, enter the multi-stage and multi-level RO system for concentration and separation, the RO produced water is returned to the production process, and the RO concentrated water is extracted to recover molybdenum; again, use special fibers for adsorption to further remove heavy metal ions; finally, use multi-effect evaporation to obtain solid salts such as potassium sulfate and sodium sulfate, and the solid salts such as potassium sulfate and sodium sulfate are separated and purified through multiple crystallizations, and the condensed water from the multi-effect evaporation is returned to the production process.

[0023] The components of process wastewater influence and help each other, and their treatment methods should fully consider the mutual influence, and the treatment plan should be a systematic and overall plan. Based on the above invention concept, the present invention makes full use of the synergy between the processes, complements each other, and interacts to form a whole, rather than a simple combination, to systematically remove turbidity, silicon and hardness in process wastewater, and remove heavy metal ions in five steps, ultimately realizing the reuse of process wastewater and the resource utilization of process wastewater.

[0024] In order to realize the resource utilization of process water, a variety of collaborative treatment processes are used. The specific collaborative treatment processes are as follows:

[0025] Process synergy 1: Step-by-step synergistic removal of multiple heavy metal ions: (1) Use manganese sand filter to remove part of the multiple heavy metal ions for the first time, and remove turbidity to prepare for the subsequent removal of heavy metal ions; (2) Add magnesium sulfate and adjust the pH with sodium hydroxide to remove multiple heavy metal ions for the second time, and remove silicon at the same time to fully ensure the progress of subsequent processes; (3) Add sodium carbonate and adjust the pH with sodium hydroxide to remove multiple heavy metal ions for the third time, and remove calcium and magnesium at the same time to prepare for multi-stage and multi-level RO concentration and separation, and to ensure that the fifth removal of multiple heavy metal ions can proceed smoothly; (4) Use softening resin to remove multiple heavy metal ions for the fourth time, and remove the remaining calcium and magnesium ions at the same time to fully ensure the multi-stage and multi-level RO concentration multiples; (5) Use special fibers for adsorption to remove multiple heavy metal ions for the fifth time, and purify salt at the same time to fully ensure the resource utilization of process water.

[0026] Process synergy 2: Multi-stage multi-stage RO synergistic concentration and separation (see Figure 2 ): 1-stage 1 RO system uses ordinary RO membrane, controls the operating pressure at 1MPa-2.5MPa, and concentrates 2-4 times. The water produced by the 1-stage 1 RO system enters the 2-stage RO system. The 2-stage RO system uses ordinary RO membrane, controls the operating pressure at 0.8MPa-1.5MPa, and concentrates 1-3 times. The water produced by the 2-stage RO system enters the 3-stage RO system. The 3-stage RO system uses ordinary RO membrane, controls the operating pressure at 0.7MPa-1.2MPa, and concentrates 3 times. The produced water of the 3-stage RO system is reused in the production process, and the concentrated water of the 1st stage RO system enters the 2nd stage RO system. The 2nd stage RO system adopts ordinary RO membrane, and the operating pressure is controlled at 3MPa-5MPa, and the concentrated water is 2-4 times. The produced water of the 2nd stage RO system, the produced water of the 1st stage RO system and the concentrated water of the 3rd stage RO system are mixed and enter the 2nd stage RO system. The concentrated water of the 2nd stage RO system enters the 3rd stage RO system. The 3rd stage RO system adopts high-pressure RO membrane, and the operating pressure is controlled at 6MPa-9MPa, and the concentrated water is 2-4 times. The concentrated water of the 3rd stage RO system enters the 4th stage RO system. The 4th stage RO system adopts ultra-high-pressure RO membrane, and the operating pressure is controlled at 10MPa-12MPa, and the concentrated water is 0.5-1 times. The produced water of the 4th stage RO system, the produced water of the 3rd stage RO system, the concentrated water of the 2nd stage RO system and the process wastewater from the softening resin are mixed and enter the 1st stage RO system; one is to enable the process water to be reused in the production process without affecting the leaching rate of uranium and molybdenum, and the other is to increase the content of molybdenum and salt.

[0027] The technical concept of the present invention is realized by the following technical scheme. The present invention provides a method for resource treatment of wastewater from an acid-based oxygen pressure leaching process of uranium-molybdenum ore, comprising the following steps:

[0028] Step 1: The process water enters the manganese sand filter, which is made of fiberglass and controlled by an automatic multi-way valve. The water inlet pressure is controlled at 0.1MPa-0.3MPa, and the permeate enters the dosing and stirring system 1;

[0029] Step 2: Add magnesium sulfate to the dosing and stirring system 1, adjust the pH to 8-10 with sodium hydroxide, control the stirring speed to 30Hz-50Hz, stir for 10min-60min, then adjust the stirring speed to 5Hz-10Hz, stir for 5min-30min, enter the asbestos plate frame filter, the operating pressure of the asbestos plate frame filter is 0.05MPa-0.2MPa, and the filtrate enters the dosing and stirring system;

[0030] Step 3: adding sodium carbonate into the dosing stirring system 2, adjusting the pH value to 8-10 with sodium hydroxide, controlling the stirring speed to 30Hz-50Hz, stirring for 10min-60min, and then adjusting the stirring speed to 5Hz-10Hz, stirring for 5min-30min, filtering through the amidoxime-modified polyacrylonitrile hollow fiber membrane for uranium extraction from seawater, using the amidoxime-modified polyacrylonitrile hollow fiber membrane for uranium extraction from seawater to perform suction solid-liquid separation, and the amidoxime-modified polyacrylonitrile hollow fiber membrane for uranium extraction from seawater produces water that enters the dosing stirring system 3;

[0031] Step 4: Add sulfuric acid into the dosing and stirring system 3, adjust the pH to 6-7, control the stirring speed to 30Hz-50Hz, stir for 10min-60min, and enter the defluorination special resin;

[0032] Step 5: The diameter of the resin tank of the special defluorination resin is controlled at 0.5m-1m, the height is controlled at 1m-2m, the flow rate is controlled at 0.5m / s-5m / s, and the process wastewater from the special defluorination resin enters the softening resin;

[0033] Step 6: The diameter of the resin tank for softening resin is controlled at 0.5m-1m, the height is controlled at 1m-2m, the flow rate is controlled at 0.5m / s-5m / s, and the process wastewater from the softening resin enters the multi-stage multi-stage RO system;

[0034] Step 7: Multi-stage multi-level RO system: The process wastewater from the softening resin enters the 1st stage 1 RO system. The 1st stage 1 RO system adopts ordinary RO membrane, controls the operating pressure at 1MPa-2.5MPa, and concentrates 2 times to 4 times. The water produced by the 1st stage 1 RO system enters the 2nd stage RO system. The 2nd stage RO system adopts ordinary RO membrane, controls the operating pressure at 0.8MPa-1.5MPa, and concentrates 1 times to 3 times. The water produced by the 2nd stage RO system enters the 3rd stage RO system. The 3rd stage RO system adopts ordinary RO membrane, controls the operating pressure at 0.7MPa-1.2MPa, and concentrates 3 times. The produced water of the 3-stage RO system is reused in the production process, the concentrated water of the 1-stage 1-stage RO system enters the 2-stage RO system, the 2-stage RO system adopts ordinary RO membrane, the operating pressure is controlled at 3MPa-5MPa, and the concentrated water is 2-4 times. The produced water of the 2-stage RO system, the produced water of the 1-stage 1-stage RO system and the concentrated water of the 3-stage RO system are mixed and enter the 2-stage RO system, the concentrated water of the 2-stage RO system enters the 3-stage RO system, the 3-stage RO system adopts high-pressure RO membrane, the operating pressure is controlled at 6MPa-9MPa, and the concentrated water of the 3-stage RO system enters the 4-stage RO system, the 4-stage RO system adopts ultra-high-pressure RO membrane, the operating pressure is controlled at 10MPa-12MPa, and the concentrated water is 0.5-1 times. The produced water of the 4-stage RO system, the produced water of the 3-stage RO system, the concentrated water of the 2-stage RO system and the process wastewater from the softening resin are mixed and enter the 1-stage 1-stage RO system, and the concentrated water of the 4-stage RO system enters the extraction system;

[0035] Step 8: The extraction system performs extraction, and the process wastewater from the extraction system enters the adsorption system. The adsorption system uses special fibers for adsorption. The filling diameter of the special fibers is controlled at 0.2m-1m, the height is controlled at 1m-5m, and the flow rate is controlled at 0.5m / s-4m / s. The process wastewater from the special fibers enters the multi-effect evaporation;

[0036] Step 9: Multi-effect evaporation is used to obtain solid salts such as potassium sulfate and sodium sulfate. The solid salts such as potassium sulfate and sodium sulfate are separated and purified through multiple crystallization. The condensed water from the multi-effect evaporation is reused in the production process.

[0037] Technical description: Step 1: In step 1, the process water passes through a manganese sand filter and the inlet pressure is controlled at 0.1MPa-0.3MPa, mainly to remove turbidity and some heavy metal ions.

[0038] Step 2: In step 2, magnesium sulfate is added to the dosing stirring system 1, and the pH is adjusted to 8-10 with sodium hydroxide in order to remove silicon and a part of heavy metal ions; the stirring speed is controlled at 30Hz-50Hz, stirred for 10min-60min, and then the stirring speed is adjusted to 5Hz-10Hz, stirred for 5min-30min, in order to allow magnesium sulfate, sodium hydroxide and silicon and various heavy metal ions to fully react and produce more precipitates; the operating pressure of the asbestos plate and frame filter is controlled at 0.05MPa-0.2MPa in order to obtain precipitates such as magnesium silicate.

[0039] Step 3: In step 3, sodium carbonate is added to the dosing stirring system 2, and the pH is adjusted to 8-10 with sodium hydroxide in order to remove calcium and magnesium ions and a portion of heavy metal ions; the stirring speed is controlled at 30Hz-50Hz, stirred for 10min-60min, and then the stirring speed is adjusted to 5Hz-10Hz, stirred for 5min-30min, in order to allow sodium carbonate, sodium hydroxide, calcium and magnesium ions and various heavy metal ions to fully react, and remove more calcium and magnesium ions and various heavy metal ions.

[0040] Step 4: In step 4, sulfuric acid is added to the dosing stirring system 3, and the stirring speed is controlled at 30Hz-50Hz and stirred for 10min-60min to remove the residual carbonate ions; the pH is adjusted to 6-7 to keep the process water neutral and slightly acidic to prepare for the removal of fluoride ions.

[0041] Step 5: In step 5, the diameter of the resin tank of the special defluorination resin is controlled at 0.5m-1m, the height is controlled at 1m-2m, and the flow rate is controlled at 0.5m / s-5m / s in order to remove fluoride ions.

[0042] Step 6: In step 6, the diameter of the resin tank for softening the resin is controlled at 0.5m-1m, the height is controlled at 1m-2m, and the flow rate is controlled at 0.5m / s-5m / s. This is to further remove calcium and magnesium ions and a part of heavy metal ions, fully ensure the concentration multiples of the multi-stage and multi-stage RO system, and reduce the energy consumption of multi-effect evaporation.

[0043] Step 7: In step 7, the 1st stage RO system of section 1 adopts ordinary RO membrane, controls the operating pressure at 1MPa-2.5MPa, and concentrates 2-4 times. The water produced by the 1st stage RO system enters the 2nd stage RO system. The 2nd stage RO system adopts ordinary RO membrane, controls the operating pressure at 0.8MPa-1.5MPa, and concentrates 1-3 times. The water produced by the 2nd stage RO system enters the 3rd stage RO system. The 3rd stage RO system adopts ordinary RO membrane, controls the operating pressure at 0.7MPa-1.2MPa, and concentrates 3 times. The produced water of the 3-stage RO system is reused in the production process, and the concentrated water of the 1st stage RO system enters the 2nd stage RO system. The 2nd stage RO system adopts ordinary RO membrane, and the operating pressure is controlled at 3MPa-5MPa, and the concentrated water is 2-4 times. The produced water of the 2nd stage RO system, the produced water of the 1st stage RO system and the concentrated water of the 3rd stage RO system are mixed and enter the 2nd stage RO system. The concentrated water of the 2nd stage RO system enters the 3rd stage RO system. The 3rd stage RO system adopts high-pressure RO membrane, and the operating pressure is controlled at 6MPa-9MPa, and the concentrated water is 2-4 times. The concentrated water of the 3rd stage RO system enters the 4th stage RO system. The 4th stage RO system adopts ultra-high-pressure RO membrane, and the operating pressure is controlled at 10MPa-12MPa, and the concentrated water is 0.5-1 times. The produced water of the 4th stage RO system, the produced water of the 3rd stage RO system, the concentrated water of the 2nd stage RO system and the process wastewater from the softening resin are mixed and enter the 1st stage RO system; one is to enable the process water to be reused in the production process without affecting the leaching rate of uranium and molybdenum, and the other is to increase the content of molybdenum and salt.

[0044] Step 8: The extraction system in step 8 performs extraction in order to extract and recover molybdenum; the process wastewater from the extraction system enters the adsorption system, and the adsorption system uses specific fibers for adsorption. The filling diameter of the specific fibers is controlled at 0.2m-1m, the height is controlled at 1m-5m, and the flow rate is controlled at 0.5m / s-4m / s, in order to further remove various heavy metal ions and purify salts.

[0045] Step 9: In step 9, multi-effect evaporation is used to obtain solid salts such as potassium sulfate and sodium sulfate. The solid salts such as potassium sulfate and sodium sulfate are separated and purified through multiple crystallizations in order to obtain industrial salts with higher purity and increase the added value of the obtained industrial salts. The condensed water from multi-effect evaporation is reused in the production process in order to reuse more process water in the production process, so that the process water can be recycled, the consumption of natural water resources can be reduced, and the cost of water use can also be reduced.

[0046] Beneficial effects: (1) The integrated process synergistically removes turbidity, silicon and hardness in process wastewater, and the five-step method removes heavy metal ions, ultimately allowing the process wastewater to be reused and realizing resource utilization of process wastewater; (2) Process water can be recycled without affecting the leaching rates of uranium and molybdenum; (3) Process water is reused more in the production process, and process water is recycled, reducing the consumption of natural water resources and the cost of water use. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] Figure 1 : Process flow chart.

[0048] Figure 2 : Multi-stage and multi-stage RO collaborative concentration and separation flow chart. DETAILED DESCRIPTION

[0049] The present invention is described in detail below in conjunction with specific embodiments. The following embodiments will help those skilled in the art to further understand the present invention, but are not intended to limit the present invention in any form. It should be noted that, for those of ordinary skill in the art, several variations and improvements may be made without departing from the concept of the present invention. These all belong to the protection scope of the present invention.

[0050] Example 1

[0051] A method for resource treatment of wastewater from an acid-based oxygen pressure leaching process of uranium-molybdenum ore, comprising the following steps:

[0052] Step 1: The process water enters the manganese sand filter, which is made of fiberglass and controlled by an automatic multi-way valve. The water inlet pressure is controlled at 0.1MPa-0.3MPa, and the permeate enters the dosing and stirring system 1;

[0053] Step 2: Add magnesium sulfate to the dosing and stirring system 1, adjust the pH to 8-10 with sodium hydroxide, control the stirring speed to 30Hz-50Hz, stir for 10min-60min, then adjust the stirring speed to 5Hz-10Hz, stir for 5min-30min, enter the asbestos plate frame filter, the operating pressure of the asbestos plate frame filter is 0.05MPa-0.2MPa, and the filtrate enters the dosing and stirring system 2;

[0054] Step 3: adding sodium carbonate into the dosing stirring system 2, adjusting the pH value to 8-10 with sodium hydroxide, controlling the stirring speed to 30Hz-50Hz, stirring for 10min-60min, and then adjusting the stirring speed to 5Hz-10Hz, stirring for 5min-30min, filtering through the amidoxime-modified polyacrylonitrile hollow fiber membrane for uranium extraction from seawater, using the amidoxime-modified polyacrylonitrile hollow fiber membrane for uranium extraction from seawater to perform suction solid-liquid separation, and the amidoxime-modified polyacrylonitrile hollow fiber membrane for uranium extraction from seawater produces water that enters the dosing stirring system 3;

[0055] Step 4: Add sulfuric acid into the dosing and stirring system 3, adjust the pH to 6-7, control the stirring speed to 30Hz-50Hz, stir for 10min-60min, and enter the defluorination special resin;

[0056] Step 5: The diameter of the resin tank of the special defluorination resin is controlled at 0.5m-1m, the height is controlled at 1m-2m, the flow rate is controlled at 0.5m / s-5m / s, and the process wastewater from the special defluorination resin enters the softening resin;

[0057] Step 6: The diameter of the resin tank for softening resin is controlled at 0.5m-1m, the height is controlled at 1m-2m, the flow rate is controlled at 0.5m / s-5m / s, and the process wastewater from the softening resin enters the multi-stage multi-stage RO system;

[0058] Step 7: Multi-stage multi-level RO system: The process wastewater from the softening resin enters the 1st stage 1 RO system. The 1st stage 1 RO system adopts ordinary RO membrane, controls the operating pressure at 1MPa-2.5MPa, and concentrates 2 times to 4 times. The water produced by the 1st stage 1 RO system enters the 2nd stage RO system. The 2nd stage RO system adopts ordinary RO membrane, controls the operating pressure at 0.8MPa-1.5MPa, and concentrates 1 times to 3 times. The water produced by the 2nd stage RO system enters the 3rd stage RO system. The 3rd stage RO system adopts ordinary RO membrane, controls the operating pressure at 0.7MPa-1.2MPa, and concentrates 3 times. The produced water of the 3-stage RO system is reused in the production process, the concentrated water of the 1-stage 1-stage RO system enters the 2-stage RO system, the 2-stage RO system adopts ordinary RO membrane, the operating pressure is controlled at 3MPa-5MPa, and the concentrated water is 2-4 times. The produced water of the 2-stage RO system, the produced water of the 1-stage 1-stage RO system and the concentrated water of the 3-stage RO system are mixed and enter the 2-stage RO system, the concentrated water of the 2-stage RO system enters the 3-stage RO system, the 3-stage RO system adopts high-pressure RO membrane, the operating pressure is controlled at 6MPa-9MPa, and the concentrated water of the 3-stage RO system enters the 4-stage RO system, the 4-stage RO system adopts ultra-high-pressure RO membrane, the operating pressure is controlled at 10MPa-12MPa, and the concentrated water is 0.5-1 times. The produced water of the 4-stage RO system, the produced water of the 3-stage RO system, the concentrated water of the 2-stage RO system and the process wastewater from the softening resin are mixed and enter the 1-stage 1-stage RO system, and the concentrated water of the 4-stage RO system enters the extraction system;

[0059] Step 8: The extraction system performs extraction, and the process wastewater from the extraction system enters the adsorption system. The adsorption system uses special fibers for adsorption. The filling diameter of the special fibers is controlled at 0.2m-1m, the height is controlled at 1m-5m, and the flow rate is controlled at 0.5m / s-4m / s. The process wastewater from the special fibers enters the multi-effect evaporation;

[0060] Step 9: multi-effect evaporation to obtain solid salts such as potassium sulfate and sodium sulfate, which are separated and purified through multiple crystallization, and the condensed water from the multi-effect evaporation is reused in the production process;

[0061] Technical description: This embodiment is to recycle process water without affecting the leaching rates of uranium and molybdenum.

[0062] Example 2

[0063] This embodiment is basically the same as the method for resource treatment of wastewater from an acid-based oxygen pressure leaching process of uranium-molybdenum ore described in Example 1, except that: in step 1, the water inlet pressure of the manganese sand filter is controlled at 0.15 MPa; in step 2, magnesium sulfate is added to the dosing stirring system 1, the pH is adjusted to 8.5 with sodium hydroxide, the stirring speed is controlled at 30 Hz, stirred for 30 minutes, and then adjusted to 10 Hz, stirred for 30 minutes, and then entered the asbestos plate frame filter, and the operating pressure of the asbestos plate frame filter is 0.1 MPa.

[0064] Technical description: In this embodiment, the water inlet pressure of the manganese sand filter in step 1 is controlled at 0.15MPa in order to remove turbidity and a part of heavy metal ions; in step 2, magnesium sulfate is added to the dosing stirring system 1, and the pH is adjusted to 8.5 with sodium hydroxide, the stirring speed is controlled at 30Hz, stirred for 30min, and then the stirring speed is adjusted to 10Hz, stirred for 30min, and then enters the asbestos plate frame filter. The operating pressure of the asbestos plate frame filter is 0.1MPa, in order to allow magnesium sulfate, sodium hydroxide and silicon and various heavy metal ions to fully react and obtain precipitates such as magnesium silicate.

[0065] Example 3

[0066] This embodiment is basically the same as the method for resource treatment of wastewater from an acid-based oxygen pressure leaching process of uranium-molybdenum ore described in Example 2, except that: in step 3, sodium carbonate is added to the dosing stirring system 2, the pH is adjusted to 10 with sodium hydroxide, the stirring speed is controlled at 45 Hz, stirred for 60 minutes, and then the stirring speed is adjusted to 5 Hz and stirred for 30 minutes.

[0067] Technical description: In step 3, sodium carbonate is added to the dosing stirring system 2, and the pH is adjusted to 10 with sodium hydroxide. The stirring speed is controlled at 45 Hz and stirred for 60 minutes. Then the stirring speed is adjusted to 5 Hz and stirred for 30 minutes. This is to allow sodium carbonate and sodium hydroxide to fully react with calcium, magnesium and various heavy metal ions, and to remove more calcium, magnesium and various heavy metal ions.

[0068] Example 4

[0069] This embodiment is basically the same as the method for resource treatment of wastewater from the acid oxygen pressure leaching process of uranium-molybdenum ore described in Example 3, except that: in step 4, sulfuric acid is added to the dosing stirring system 3, the pH is adjusted to 6, the stirring speed is controlled at 50 Hz, and the stirring is performed for 60 minutes.

[0070] Technical description: In step 4, sulfuric acid is added to the dosing stirring system 3, the pH is adjusted to 6, the stirring speed is controlled at 50 Hz, and the stirring is performed for 60 minutes. This is to keep the process water neutral and slightly acidic, in preparation for the removal of fluoride ions.

[0071] Example 5

[0072] This embodiment is basically the same as the method for resource treatment of wastewater from the acid oxygen pressure leaching process of uranium-molybdenum ore described in Example 4, except that: in step 5, the diameter of the resin tank of the special defluorination resin is controlled at 0.5m, the height is controlled at 1.5m, and the flow rate is controlled at 3m / s.

[0073] Technical description: In step 5, the diameter of the resin tank for the fluorine removal resin is controlled at 0.5m, the height is controlled at 1.5m, and the flow rate is controlled at 3m / s in order to remove fluoride ions.

[0074] Example 6

[0075] This embodiment is basically the same as the method for resource treatment of wastewater from the acid oxygen pressure leaching process of uranium-molybdenum ore described in Example 5, except that: in step 6, the diameter of the resin tank for softening the resin is controlled at 1m, the height is controlled at 2m, and the flow rate is controlled at 4m / s.

[0076] Technical description: In step 6, the resin tank for softening the resin is controlled at 1m in diameter, 2m in height, and 4m / s in flow rate in order to further remove calcium and magnesium ions and a portion of heavy metal ions, fully ensure the concentration multiples of the multi-stage and multi-stage RO system, and reduce the energy consumption of multi-effect evaporation.

[0077] Example 7

[0078] This embodiment is basically the same as the method for resource treatment of wastewater from an acid-based oxygen pressure leaching process of uranium-molybdenum ore described in Example 1, except that: in step 7, the first-stage 1-level RO system adopts an ordinary RO membrane, controls the operating pressure at 2.5 MPa, and concentrates 3 times. The water produced by the first-stage 1-level RO system enters the second-stage RO system. The second-stage RO system adopts an ordinary RO membrane, controls the operating pressure at 1.5 MPa, and concentrates 1 times. The water produced by the second-stage RO system enters the third-stage RO system. The third-stage RO system adopts an ordinary RO membrane, controls the operating pressure at 1 MPa, and concentrates 3 times. The water produced by the third-stage RO system is reused in the production process.

[0079] Technical description: In step 7, the 1st stage RO system adopts ordinary RO membrane, controls the operating pressure at 2.5MPa, and concentrates 3 times. The water produced by the 1st stage RO system enters the 2nd stage RO system. The 2nd stage RO system adopts ordinary RO membrane, controls the operating pressure at 1.5MPa, and concentrates 1 times. The water produced by the 2nd stage RO system enters the 3rd stage RO system. The 3rd stage RO system adopts ordinary RO membrane, controls the operating pressure at 1MPa, and concentrates 3 times. The water produced by the 3rd stage RO system is reused in the production process in order to enable the process water to be reused in the production process without affecting the leaching rate of uranium and molybdenum.

[0080] Example 8

[0081] This embodiment is basically the same as the method for resource treatment of wastewater from the acid oxygen pressure leaching process of uranium-molybdenum ore described in Example 7, with the difference being that in step 7, the concentrate from the 1st-stage RO system enters the 2nd-stage RO system, which adopts an ordinary RO membrane, controls the operating pressure at 5 MPa, and concentrates 3 times; the produced water from the 2nd-stage RO system, the produced water from the 1st-stage RO system, and the concentrate from the 3rd-stage RO system are mixed and enter the 2nd-stage RO system; the concentrate from the 2nd-stage RO system enters the 3rd-stage RO system, which adopts a high-pressure RO membrane, controls the operating pressure at 8 MPa, and concentrates 3 times; and the concentrate from the 3rd-stage RO system enters the 4th-stage RO system.

[0082] Technical description: In step 7, the concentrated water from the 1st stage RO system enters the 2nd stage RO system. The 2nd stage RO system adopts ordinary RO membrane, and the operating pressure is controlled at 5MPa. It is concentrated 3 times. The produced water from the 2nd stage RO system, the produced water from the 1st stage RO system and the concentrated water from the 3rd stage RO system are mixed and enter the 2nd stage RO system. The concentrated water from the 2nd stage RO system enters the 3rd stage RO system. The 3rd stage RO system adopts high-pressure RO membrane, and the operating pressure is controlled at 8MPa. It is concentrated 3 times. The concentrated water from the 3rd stage RO system enters the 4th stage RO system. This is to increase the content of molybdenum and salt step by step and reduce energy consumption.

[0083] Example 9

[0084] This embodiment is basically the same as the method for resource treatment of wastewater from the acid oxygen pressure leaching process of uranium-molybdenum ore described in Example 8, with the difference being that in step 7, the 4-stage RO system adopts an ultra-high pressure RO membrane, controls the operating pressure at 12 MPa, and concentrates by 0.5 times. The water produced by the 4-stage RO system, the water produced by the 3-stage RO system, the concentrated water of the 2-stage RO system, and the process wastewater from the softening resin are mixed and enter the 1-stage 1-stage RO system, and the concentrated water of the 4-stage RO system enters the extraction system.

[0085] Technical description: In step 7, the 4-stage RO system uses an ultra-high pressure RO membrane, controls the operating pressure at 12MPa, and concentrates by 0.5 times. The water produced by the 4-stage RO system, the water produced by the 3-stage RO system, the concentrated water of the 2-stage RO system, and the process wastewater from the softening resin are mixed and then enter the 1-stage 1-stage RO system. The concentrated water of the 4-stage RO system enters the extraction system in order to further increase the content of molybdenum and salt, in preparation for the extraction of molybdenum and multi-effect evaporation.

[0086] Example 10

[0087] This embodiment is basically the same as the method for resource-based treatment of wastewater from an acid-based oxygen pressure leaching process of uranium-molybdenum ore described in Example 1, except that: in step 1, the water inlet pressure of the manganese sand filter is controlled at 0.1 MPa; in step 2, magnesium sulfate is added to the dosing stirring system 1, the pH is adjusted to 10 with sodium hydroxide, the stirring speed is controlled at 50 Hz, stirring for 10 min, and then the stirring speed is adjusted to 5 Hz, stirring for 5 min, and then the asbestos plate frame filter is entered, the operating pressure of the asbestos plate frame filter is 0.2 MPa, and the filtrate enters the dosing stirring system 2; in step 3, sodium carbonate is added to the dosing stirring system 2, the pH is adjusted to 10 with sodium hydroxide, the stirring speed is controlled at 50 Hz, stirring for 60 min, and then the stirring speed is adjusted at 10 Hz, stirring for 5 min; in step 4, sulfuric acid is added to the dosing stirring system 3, the pH is adjusted to 6.5, the stirring speed is controlled at 50 Hz, stirring for 60 min, and then the defluorination special resin is entered; in step 5, the diameter of the resin tank of the defluorination special resin is controlled at 0.5 m, and the height is controlled The diameter of the resin tank of the softening resin in step 6 is controlled at 1m, the height is controlled at 2m, the flow rate is controlled at 4m / s, and the process wastewater from the softening resin enters the multi-stage multi-level RO system; in step 7, the process wastewater from the softening resin enters the 1st stage 1 RO system, the 1st stage 1 RO system adopts ordinary RO membrane, the operating pressure is controlled at 2.5MPa, and it is concentrated 4 times. The water produced by the 1st stage 1 RO system enters the 2nd stage RO system, the 2nd stage RO system adopts ordinary RO membrane, the operating pressure is controlled at 1.5MPa, and it is concentrated 3 times. The water produced by the 2nd stage RO system enters the 3rd stage RO system, the 3rd stage RO system adopts ordinary RO membrane, the operating pressure is controlled at 0.7MPaMPa, and it is concentrated 3 times. The water produced by the 3-stage RO system is reused in the production process. The concentrated water of the 1st stage RO system enters the 2nd stage RO system. The 2nd stage RO system adopts ordinary RO membrane, and the operating pressure is controlled at 5MPa. The concentrated water is concentrated by 2 times. The water produced by the 2nd stage RO system, the water produced by the 1st stage RO system and the concentrated water of the 3rd stage RO system are mixed and enter the 2nd stage RO system. The concentrated water of the 2nd stage RO system enters the 3rd stage RO system. The 3rd stage RO system adopts high-pressure RO membrane, and the operating pressure is controlled at 9MPa. The concentrated water enters the 4th stage RO system. The 4th stage RO system adopts ultra-high-pressure RO membrane, and the operating pressure is controlled at 12MPa. The concentrated water enters the 1st stage RO system. The concentrated water of the 4th stage RO system, the water produced by the 3rd stage RO system, the concentrated water of the 2nd stage RO system and the process wastewater from the softening resin are mixed and enter the 1st stage RO system. The concentrated water of the 4th stage RO system enters the extraction system. In step 8, the extraction system performs extraction, and the process wastewater from the extraction system enters the adsorption system. The adsorption system adopts special fibers for adsorption. The filling diameter of the special fibers is controlled at 1m, the height is controlled at 3m, and the flow rate is controlled at 0.5m / s, the process wastewater from the special fiber enters the multi-effect evaporator; in step 9, the multi-effect evaporator obtains solid salts such as potassium sulfate and sodium sulfate, which are separated and purified through multiple crystallization, and the condensed water from the multi-effect evaporator is reused in the production process.

[0088] Technical description: The operating parameters and processes in steps 1-9 are adjusted so that the process water can be recycled without affecting the leaching rates of uranium and molybdenum.

Claims

1. A method for recycling wastewater from an acid-based oxygen pressure leaching process of uranium-molybdenum ore, comprising the following steps: Step 1: The process water enters the manganese sand filter, which is made of fiberglass and controlled by an automatic multi-way valve. The water inlet pressure is controlled at 0.1MPa-0.3MPa, and the permeate enters the dosing and stirring system 1; Step 2: Add magnesium sulfate to the dosing and stirring system 1, adjust the pH to 8-10 with sodium hydroxide, control the stirring speed to 30Hz-50Hz, stir for 10min-60min, then adjust the stirring speed to 5Hz-10Hz, stir for 5min-30min, enter the asbestos plate frame filter, the operating pressure of the asbestos plate frame filter is 0.05MPa-0.2MPa, and the filtrate enters the dosing and stirring system 2; Step 3: adding sodium carbonate into the dosing stirring system 2, adjusting the pH value to 8-10 with sodium hydroxide, controlling the stirring speed to 30Hz-50Hz, stirring for 10min-60min, and then adjusting the stirring speed to 5Hz-10Hz, stirring for 5min-30min, filtering through the amidoxime-modified polyacrylonitrile hollow fiber membrane for uranium extraction from seawater, using the amidoxime-modified polyacrylonitrile hollow fiber membrane for uranium extraction from seawater to perform suction solid-liquid separation, and the amidoxime-modified polyacrylonitrile hollow fiber membrane for uranium extraction from seawater produces water that enters the dosing stirring system 3; Step 4: Add sulfuric acid into the dosing and stirring system 3, adjust the pH to 6-7, control the stirring speed to 30Hz-50Hz, stir for 10min-60min, and enter the defluorination special resin; Step 5: The diameter of the resin tank of the special defluorination resin is controlled at 0.5m-1m, the height is controlled at 1m-2m, the flow rate is controlled at 0.5m / s-5m / s, and the process wastewater from the special defluorination resin enters the softening resin; Step 6: The diameter of the resin tank for softening resin is controlled at 0.5m-1m, the height is controlled at 1m-2m, the flow rate is controlled at 0.5m / s-5m / s, and the process wastewater from the softening resin enters the multi-stage multi-stage RO system; Step 7: Multi-stage multi-level RO system: The process wastewater from the softening resin enters the 1st stage 1 RO system. The 1st stage 1 RO system adopts ordinary RO membrane, controls the operating pressure at 1MPa-2.5MPa, and concentrates 2 times to 4 times. The water produced by the 1st stage 1 RO system enters the 2nd stage RO system. The 2nd stage RO system adopts ordinary RO membrane, controls the operating pressure at 0.8MPa-1.5MPa, and concentrates 1 times to 3 times. The water produced by the 2nd stage RO system enters the 3rd stage RO system. The 3rd stage RO system adopts ordinary RO membrane, controls the operating pressure at 0.7MPa-1.2MPa, and concentrates 3 times. The produced water of the 3-stage RO system is reused in the production process, the concentrated water of the 1-stage 1-stage RO system enters the 2-stage RO system, the 2-stage RO system adopts ordinary RO membrane, the operating pressure is controlled at 3MPa-5MPa, and the concentrated water is 2-4 times. The produced water of the 2-stage RO system, the produced water of the 1-stage 1-stage RO system and the concentrated water of the 3-stage RO system are mixed and enter the 2-stage RO system, the concentrated water of the 2-stage RO system enters the 3-stage RO system, the 3-stage RO system adopts high-pressure RO membrane, the operating pressure is controlled at 6MPa-9MPa, and the concentrated water of the 3-stage RO system enters the 4-stage RO system, the 4-stage RO system adopts ultra-high-pressure RO membrane, the operating pressure is controlled at 10MPa-12MPa, and the concentrated water is 0.5-1 times. The produced water of the 4-stage RO system, the produced water of the 3-stage RO system, the concentrated water of the 2-stage RO system and the process wastewater from the softening resin are mixed and enter the 1-stage 1-stage RO system, and the concentrated water of the 4-stage RO system enters the extraction system; Step 8: The extraction system performs extraction, and the process wastewater from the extraction system enters the adsorption system. The adsorption system uses special fibers for adsorption. The filling diameter of the special fibers is controlled at 0.2m-1m, the height is controlled at 1m-5m, and the flow rate is controlled at 0.5m / s-4m / s. The process wastewater from the special fibers enters the multi-effect evaporation; Step 9: Multi-effect evaporation is used to obtain solid salts such as potassium sulfate and sodium sulfate. The solid salts such as potassium sulfate and sodium sulfate are separated and purified through multiple crystallization. The condensed water from the multi-effect evaporation is reused in the production process.

2. The method for resource treatment of wastewater from acid oxygen pressure leaching of uranium-molybdenum ore according to claim 1, characterized in that: In step 1, the water inlet pressure of the manganese sand filter is controlled at 0.15MPa; in step 2, magnesium sulfate is added to the dosing stirring system 1, the pH is adjusted to 8.5 with sodium hydroxide, the stirring speed is controlled at 30Hz, stirred for 30min, and then the stirring speed is adjusted to 10Hz, stirred for 30min, and then enters the asbestos plate frame filter, and the operating pressure of the asbestos plate frame filter is 0.1MPa.

3. The method for resource treatment of wastewater from acid oxygen pressure leaching of uranium-molybdenum ore according to claim 2, characterized in that: In step 3, sodium carbonate is added to the dosing stirring system 2, and the pH is adjusted to 10 with sodium hydroxide. The stirring speed is controlled at 45 Hz and stirred for 60 minutes, and then the stirring speed is adjusted to 5 Hz and stirred for 30 minutes.

4. The method for resource treatment of wastewater from acid oxygen pressure leaching of uranium-molybdenum ore according to claim 3, characterized in that: In step 4, sulfuric acid is added into the dosing stirring system 3, the pH is adjusted to 6, the stirring speed is controlled at 50 Hz, and the stirring is performed for 60 minutes.

5. The method for resource treatment of wastewater from acid oxygen pressure leaching of uranium-molybdenum ore according to claim 4, characterized in that: In step 5, the diameter of the resin tank for the special defluorination resin is controlled at 0.5m, the height is controlled at 1.5m, and the flow rate is controlled at 3m / s.

6. The method for resource treatment of wastewater from acid-oxygen pressure leaching of uranium-molybdenum ore according to claim 5, characterized in that: In step 6, the diameter of the resin tank for softening the resin is controlled at 1 m, the height is controlled at 2 m, and the flow rate is controlled at 4 m / s.

7. The method for resource treatment of wastewater from acid oxygen pressure leaching of uranium-molybdenum ore according to claim 1, characterized in that: In step 7, the first-stage RO system of section 1 adopts ordinary RO membrane, controls the operating pressure at 2.5MPa, and concentrates 3 times. The water produced by the first-stage RO system enters the second-stage RO system. The second-stage RO system adopts ordinary RO membrane, controls the operating pressure at 1.5MPa, and concentrates 1 times. The water produced by the second-stage RO system enters the third-stage RO system. The third-stage RO system adopts ordinary RO membrane, controls the operating pressure at 1MPa, and concentrates 3 times. The water produced by the third-stage RO system is reused in the production process.

8. The method for resource treatment of wastewater from acid-oxygen pressure leaching of uranium-molybdenum ore according to claim 7, characterized in that: In step 7, the concentrated water from the 1st stage RO system enters the 2nd stage RO system, which adopts ordinary RO membrane, controls the operating pressure at 5MPa, and concentrates 3 times. The produced water from the 2nd stage RO system, the produced water from the 1st stage RO system and the concentrated water from the 3rd stage RO system are mixed and enter the 2nd stage RO system. The concentrated water from the 2nd stage RO system enters the 3rd stage RO system, which adopts high-pressure RO membrane, controls the operating pressure at 8MPa, and concentrates 3 times. The concentrated water from the 3rd stage RO system enters the 4th stage RO system.

9. The method for resource treatment of wastewater from acid-oxygen pressure leaching of uranium-molybdenum ore according to claim 8, characterized in that: In step 7, the 4-stage RO system uses an ultra-high pressure RO membrane, controls the operating pressure at 12 MPa, and concentrates by 0.5 times. The water produced by the 4-stage RO system, the water produced by the 3-stage RO system, the concentrated water of the 2-stage RO system and the process wastewater from the softening resin are mixed and enter the 1-stage 1-stage RO system, and the concentrated water of the 4-stage RO system enters the extraction system.

10. The method for resource treatment of wastewater from acid-oxygen pressure leaching of uranium-molybdenum ore according to claim 1, characterized in that: In step 1, the water inlet pressure of the manganese sand filter is controlled at 0.1MPa; in step 2, magnesium sulfate is added to the dosing stirring system 1, the pH is adjusted to 10 with sodium hydroxide, the stirring speed is controlled at 50Hz, stirred for 10min, and then the stirring speed is adjusted to 5Hz, stirred for 5min, and then the asbestos plate frame filter is entered. The operating pressure of the asbestos plate frame filter is 0.2MPa, and the filtrate enters the dosing stirring system 2; in step 3, sodium carbonate is added to the dosing stirring system 2, the pH is adjusted to 10 with sodium hydroxide, the stirring speed is controlled at 50Hz, stirred for 60min, and then the stirring speed is adjusted at 10Hz, stirred for 5min; in step 4, sulfuric acid is added to the dosing stirring system 3, the pH is adjusted to 6.5, the stirring speed is controlled at 50Hz, stirred for 60min, and the defluorination special resin is entered; in step 5, the diameter of the resin tank of the defluorination special resin is controlled at 0.5m, and the height is controlled The diameter of the resin tank of the softening resin in step 6 is controlled at 1m, the height is controlled at 2m, the flow rate is controlled at 4m / s, and the process wastewater from the softening resin enters the multi-stage multi-level RO system; in step 7, the process wastewater from the softening resin enters the 1st stage 1 RO system, the 1st stage 1 RO system adopts ordinary RO membrane, the operating pressure is controlled at 2.5MPa, and it is concentrated 4 times. The water produced by the 1st stage 1 RO system enters the 2nd stage RO system, the 2nd stage RO system adopts ordinary RO membrane, the operating pressure is controlled at 1.5MPa, and it is concentrated 3 times. The water produced by the 2nd stage RO system enters the 3rd stage RO system, the 3rd stage RO system adopts ordinary RO membrane, the operating pressure is controlled at 0.7MPaMPa, and it is concentrated 3 times. The produced water of the 3-stage RO system is reused in the production process. The concentrated water of the 1st stage RO system enters the 2nd stage RO system. The 2nd stage RO system adopts ordinary RO membrane and controls the operating pressure at 5MPa. The concentrated water is concentrated by 2 times. The produced water of the 2nd stage RO system, the produced water of the 1st stage RO system and the concentrated water of the 3rd stage RO system are mixed and enter the 2nd stage RO system. The concentrated water of the 2nd stage RO system enters the 3rd stage RO system. The 3rd stage RO system adopts high-pressure RO membrane and controls the operating pressure at 9MPa. The concentrated water enters the 4th stage RO system. The 4th stage RO system adopts ultra-high-pressure RO membrane and controls the operating pressure at 12MPa. The concentrated water enters the 4th stage RO system. The produced water of the 4th stage RO system, the 3rd stage RO system The RO system produced water, the 2nd-stage RO system concentrated water and the process wastewater from the softening resin are mixed and then enter the 1st-stage 1st-stage RO system, and the 4th-stage RO system concentrated water enters the extraction system; in step 8, the extraction system performs extraction, and the process wastewater from the extraction system enters the adsorption system. The adsorption system uses special fibers for adsorption, and the filling diameter of the special fibers is controlled at 1m, the height is controlled at 3m, and the flow rate is controlled at 0.5m / s. The process wastewater from the special fibers enters the multi-effect evaporation; in step 9, the multi-effect evaporation obtains solid salts such as potassium sulfate and sodium sulfate, and the solid salts such as potassium sulfate and sodium sulfate are separated and purified through multiple crystallization, and the condensed water of the multi-effect evaporation is reused in the production process.

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