A method for resource treatment of wastewater from the acid oxygen pressure leaching process of uranium molybdenum ore

Abstract

The present invention relates to the field of industrial wastewater treatment, and particularly to a method for resource treatment of wastewater from the acid oxygen pressure leaching process of uranium molybdenum ore. The present invention provides a method for resource treatment of wastewater from the acid oxygen pressure leaching process of uranium molybdenum ore, including a manganese sand filter, a dosing and stirring system 1, an asbestos plate frame filter, a dosing and stirring system 2, a dosing and stirring system 3, a special defluorination resin, a softening resin, a multi-stage and multi-level RO system, an extraction system, an adsorption system, and a multi-effect evaporation. The integrated process of the present invention collaboratively removes turbidity, silicon, and hardness in the process wastewater, removes heavy metal ions by a five-step method, ultimately enables the reuse of the process wastewater without affecting the leaching rates of uranium and molybdenum, realizes the resource utilization of the process wastewater, reduces the consumption of natural water resources, and can also reduce the water use cost.

Description

Technical Field

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

[0002] With the accelerated development of industrialization and informatization, the social production's demand for energy and chemical products is also increasing continuously. Especially for uranium used in nuclear fuel and the development of the nuclear industry, and uranium is also used in nuclear scientific research and the development of new reactor technologies. Molybdenum, as a key metal in the industry, has wide uses and importance in the steel industry, aerospace industry, electronics and electrical industries due to its excellent physical and chemical properties. The main sources of uranium and molybdenum resources are still traditional land mining, and associated uranium molybdenum ore is a typical mineral for co - development of uranium and molybdenum. However, the mineral processing technological process is complex, the extraction rate of target resources is not high, the water demand is large, and problems such as the post - treatment of "industrial three wastes" bring challenges to the maximum recovery rate of mineral development and resource utilization. Especially, the treatment problem of industrial wastewater generated after ore washing and separation, grinding and pulp adjustment, and hydraulic transportation in the technological process has attracted great attention. On the one hand, environmental protection issues need to be considered for process wastewater. The wastewater contains various ions, which will pose a serious threat to the ecological environment and human health if not effectively treated. On the other hand, considering economic benefits, the treated water can be reused in the production process again, reducing the consumption of natural water resources and also lowering the water use cost. Therefore, in the process of uranium molybdenum mineral processing, how to achieve zero discharge of wastewater treatment and realize the recycling of water in the production line is a key problem in the mineral mining industry and also a research requirement and research goal in the chemical and materials fields.

[0003] There are the following problems in the reuse of the existing process wastewater:

[0004] Problem 1: The problem that during the multiple - cycle of process water in a closed - loop system, the easily soluble impurity ions in the wastewater accumulate continuously during the cycle, which seriously affects the leaching rate of oxygen pressure acid leaching of molybdenum.

[0005] The multiple - cycle of process water in a closed - loop system results in a gradual increase in the ion concentration in the wastewater. Monovalent cations in the water body of the production link, such as K + , Na + , NH4 +The accumulation leads to a significant decrease in the leaching rate of molybdenum, and the decrease amplitude usually reaches 6% - 8%. On the one hand, monovalent cations usually have high solubility, and their interaction with common precipitants is weak. They do not form insoluble compounds as easily as polyvalent cations, and monovalent cations usually have weak adsorption ability on the surface of adsorption materials and are difficult to be effectively removed by adsorption method. Many commonly used adsorption materials (such as activated carbon, zeolite, etc.) have poor adsorption ability for monovalent cations. Therefore, it is very difficult for them to be removed from wastewater by simple physical methods (such as precipitation or filtration) and adsorption method. On the other hand, there are often various ions in wastewater, with high ionic strength, and there will be a competitive effect between monovalent cations and other polyvalent cations or cations, resulting in a reduction in the removal efficiency. Therefore, the reuse of process water seriously affects the leaching rate of molybdenum.

[0006] Problem 2: The problem that process water cannot be directly discharged.

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

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

[0009] The existing technologies have the following technical difficulties in comprehensively solving the above problems:

[0010] Technical difficulty 1: The influence of high salinity on reverse osmosis.

[0011] First of all, high salinity will increase the osmotic pressure, resulting in too high operating pressure of reverse osmosis, leading to high operating costs and affecting the service life of reverse osmosis membranes; secondly, high salinity will cause the salt content of the produced water in the reverse osmosis system to be high, failing to achieve the purpose of high - level desalination; thirdly, various metal ions affect and interfere with the desalination rate of reverse osmosis membranes; finally, various metal ions will produce precipitates with anions during reverse osmosis concentration, resulting in reverse osmosis blockage, and seriously leading to the scrapping of reverse osmosis membranes.

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

[0013] Process wastewater contains components such as silica gel, resulting in high turbidity of water. The reverse osmosis membrane requires the influent turbidity to be less than 1 NTU. When the turbidity exceeds this value, it will cause pollution and fouling of reverse osmosis, resulting in the reverse osmosis membrane being unable to operate normally and seriously affecting the service life of the reverse osmosis membrane.

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

[0015] High-hardness water can have a serious impact on the reverse osmosis system. The main manifestations are that hardness ions such as calcium and magnesium form scale on the membrane surface, resulting in 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, leading to an increase in maintenance costs.

[0016] Technical difficulty 4: The components in the wastewater interact and interfere with each other, making it difficult to carry out resource treatment.

[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 in turn affect the removal of other heavy metal ions; the multiple ions result in a high salt content, making the treatment process complex. It is not possible to achieve water reuse simply by reverse osmosis and multi-effect evaporation. Using technologies other than reverse osmosis for treatment is difficult to sufficiently reduce the ionic strength in the process wastewater. The treatment of process wastewater requires strict control to avoid the impact of the pre-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 concepts are proposed (see Figure 1 ):

[0019] Regarding technical difficulty 1: It is necessary to remove metal ions step by step using different processes. First, add magnesium ions to remove high-turbidity substances such as silicon; second, use the double-alkali method to remove metal ions such as calcium, magnesium, and iron; finally, further remove calcium and magnesium and other metal ions through softening resin, and then use fluorine resin to remove fluoride ions in the water.

[0020] Regarding technical difficulty 2: The combined process of sand filtration, precision security filter, and chemical dosing for flocculation and precipitation reduces the wastewater turbidity to below 1 NTU, meeting the inlet water requirements of the reverse osmosis membrane. Remove large particulate suspensions and impurities in the wastewater through sand filtration, and then use a precision security filter for further filtration to ensure that the inlet water turbidity reaches below 1 NTU. Combining the chemical dosing for flocculation and precipitation process, add flocculants to aggregate the tiny particles in the water into larger precipitates for subsequent filtration treatment. This process can significantly reduce the turbidity of water and meet the inlet water standard of the reverse osmosis system. Finally, due to the presence of silicon, silicon scale will form on the surface of the reverse osmosis membrane, seriously affecting the performance and life of the membrane. Therefore, silicon in the water needs to be specifically removed 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 a precipitate to further protect 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 synergy for removing multiple heavy metal ions: (1) Use a manganese sand filter to remove a part of multiple heavy metal ions for the first time, and at the same time remove turbidity to prepare for further removing 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 at the same time remove silicon 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 at the same time remove calcium and magnesium to prepare for multi-stage and multi-level RO concentration and separation, and to ensure the smooth progress of the removal of multiple heavy metal ions for the fifth time; (4) Use softening resin to remove multiple heavy metal ions for the fourth time, and at the same time remove the remaining calcium and magnesium ions to fully ensure the concentration multiple of multi-stage and multi-level RO; (5) Use specific fibers for adsorption to remove multiple heavy metal ions for the fifth time, and at the same time purify the salt to fully ensure the resource utilization of process water.

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

[0027] The technical concept of the present invention is realized through the following technical solutions. The present invention provides a method for resource treatment of acid pressure leaching process wastewater of uranium-molybdenum ore, including the following steps:

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

[0029] Step 2: Magnesium sulfate is added to the chemical dosing and mixing system 1, and the pH is adjusted to 8 - 10 with sodium hydroxide. The stirring speed is controlled at 30 Hz - 50 Hz and stirred for 10 min - 60 min, then the stirring speed is adjusted to 5 Hz - 10 Hz and stirred for 5 min - 30 min. It then enters the asbestos plate frame filter. The operating pressure of the asbestos plate frame filter is 0.05 MPa - 0.2 MPa, and the filtrate enters the chemical dosing and mixing system;

[0030] Step 3: Sodium carbonate is added to the chemical dosing and mixing system 2, and the pH is adjusted to 8 - 10 with sodium hydroxide. The stirring speed is controlled at 30 Hz - 50 Hz and stirred for 10 min - 60 min, then the stirring speed is adjusted to 5 Hz - 10 Hz and stirred for 5 min - 30 min. It is then filtered through a amidoxime - modified polyacrylonitrile hollow fiber membrane for uranium extraction from seawater. The amidoxime - modified polyacrylonitrile hollow fiber membrane for uranium extraction from seawater uses a negative pressure suction form for solid - liquid separation, and the produced water of the amidoxime - modified polyacrylonitrile hollow fiber membrane for uranium extraction from seawater enters the chemical dosing and mixing system 3;

[0031] Step 4: Sulfuric acid is added to the chemical dosing and mixing system 3, and the pH is adjusted to 6 - 7. The stirring speed is controlled at 30 Hz - 50 Hz and stirred for 10 min - 60 min, then it enters the special resin for defluorination;

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

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

[0034] Step 7: Multi-stage and multi-level RO system: The process wastewater coming out of the softening resin enters the 1st-stage and 1st-level RO system. The 1st-stage and 1st-level RO system uses ordinary RO membranes, with the operating pressure controlled at 1 MPa - 2.5 MPa, and the concentration factor is 2 - 4 times. The water produced by the 1st-stage and 1st-level RO system enters the 2nd-level RO system. The 2nd-level RO system uses ordinary RO membranes, with the operating pressure controlled at 0.8 MPa - 1.5 MPa, and the concentration factor is 1 - 3 times. The water produced by the 2nd-level RO system enters the 3rd-level RO system. The 3rd-level RO system uses ordinary RO membranes, with the operating pressure controlled at 0.7 MPa - 1.2 MPa, and the concentration factor is 3 times. The water produced by the 3rd-level RO system is recycled for the production process. The concentrated water of the 1st-stage and 1st-level RO system enters the 2nd-stage RO system. The 2nd-stage RO system uses ordinary RO membranes, with the operating pressure controlled at 3 MPa - 5 MPa, and the concentration factor is 2 - 4 times. The water produced by the 2nd-stage RO system, the water produced by the 1st-stage and 1st-level RO system, and the concentrated water of the 3rd-level RO system are mixed and then enter the 2nd-level RO system. The concentrated water of the 2nd-stage RO system enters the 3rd-stage RO system. The 3rd-stage RO system uses high-pressure RO membranes, with the operating pressure controlled at 6 MPa - 9 MPa, and the concentration factor is 2 - 4 times. The concentrated water of the 3rd-stage RO system enters the 4th-stage RO system. The 4th-stage RO system uses ultra-high-pressure RO membranes, with the operating pressure controlled at 10 MPa - 12 MPa, and the concentration factor is 0.5 - 1 times. The water produced by the 4th-stage RO system, the water produced by the 3rd-stage RO system, the concentrated water of the 2nd-level RO system, and the process wastewater coming out of the softening resin are mixed and then enter the 1st-stage and 1st-level RO system. The concentrated water of the 4th-stage RO system enters the extraction system;

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

[0036] Step 9: The multi-effect evaporation obtains 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 recycled for the production process.

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

[0038] Step 2: Add magnesium sulfate to the chemical dosing and stirring system 1, and adjust the pH to 8 - 10 with sodium hydroxide to remove silicon and some heavy metal ions. Control the stirring speed at 30 Hz - 50 Hz and stir for 10 min - 60 min, then adjust the stirring speed to 5 Hz - 10 Hz and stir for 5 min - 30 min to allow magnesium sulfate, sodium hydroxide, silicon and various heavy metal ions to react fully and produce more precipitates. Control the operating pressure of the asbestos plate frame filter at 0.05 MPa - 0.2 MPa to obtain precipitates such as magnesium silicate.

[0039] Step 3: Add sodium carbonate to the chemical dosing and stirring system 2, and adjust the pH to 8 - 10 with sodium hydroxide to remove calcium and magnesium ions and some heavy metal ions. Control the stirring speed at 30 Hz - 50 Hz and stir for 10 min - 60 min, then adjust the stirring speed to 5 Hz - 10 Hz and stir for 5 min - 30 min to allow sodium carbonate, sodium hydroxide to react fully with calcium and magnesium ions and various heavy metal ions, and remove more calcium and magnesium ions and various heavy metal ions.

[0040] Step 4: Add sulfuric acid to the chemical dosing and stirring system 3, control the stirring speed at 30 Hz - 50 Hz and stir for 10 min - 60 min to remove the residual carbonate. Adjust the pH to 6 - 7 to make the process water slightly acidic while maintaining neutrality, in preparation for the removal of fluoride ions.

[0041] Step 5: Control the diameter of the resin tank of the fluoride - removing special resin at 0.5 m - 1 m, the height at 1 m - 2 m, and the flow rate at 0.5 m / s - 5 m / s to remove fluoride ions.

[0042] Step 6: Control the diameter of the resin tank of the softening resin at 0.5 m - 1 m, the height at 1 m - 2 m, and the flow rate at 0.5 m / s - 5 m / s to further remove calcium and magnesium ions and some heavy metal ions, fully ensure the concentration multiple of the multi - stage and multi - level RO system, and reduce the energy consumption of multi - effect evaporation.

[0043] Step 7: In step 7, the 1-stage and 1-pass RO system uses a common RO membrane, with the operating pressure controlled at 1 MPa - 2.5 MPa, and the concentration factor is 2 - 4 times. The water produced by the 1-stage and 1-pass RO system enters the 2-stage RO system. The 2-stage RO system uses a common RO membrane, with the operating pressure controlled at 0.8 MPa - 1.5 MPa, and the concentration factor is 1 - 3 times. The water produced by the 2-stage RO system enters the 3-stage RO system. The 3-stage RO system uses a common RO membrane, with the operating pressure controlled at 0.7 MPa - 1.2 MPa, and the concentration factor is 3 times. The water produced by the 3-stage RO system is recycled for the production process. The concentrated water of the 1-stage and 1-pass RO system enters the 2-stage RO system. The 2-stage RO system uses a common RO membrane, with the operating pressure controlled at 3 MPa - 5 MPa, and the concentration factor is 2 - 4 times. The water produced by the 2-stage RO system, the water produced by the 1-stage and 1-pass RO system, and the concentrated water of the 3-stage RO system are mixed and then 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 uses a high-pressure RO membrane, with the operating pressure controlled at 6 MPa - 9 MPa, and the concentration factor is 2 - 4 times. The concentrated water of the 3-stage RO system enters the 4-stage RO system. The 4-stage RO system uses an ultra-high-pressure RO membrane, with the operating pressure controlled at 10 MPa - 12 MPa, and the concentration factor is 0.5 - 1 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 and 1-pass RO system. One is to enable the process water to be recycled for the production process without affecting the leaching rates of uranium and molybdenum, and the other is to increase the contents of molybdenum and salts.

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

[0045] Step 9: In step 9, solid salts such as potassium sulfate and sodium sulfate are obtained by multi-effect evaporation. The solid salts such as potassium sulfate and sodium sulfate are separated and purified through multiple crystallization 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 recycled for the production process to enable more process water to be recycled for the production process, realize the recycling of process water, reduce the consumption of natural water resources, and also reduce the water use cost.

[0046] Beneficial effects: (1) The integrated process synergistically removes turbidity, silicon, and hardness in the process wastewater, and removes heavy metal ions by a five-step method, ultimately enabling the recycling of the process wastewater and realizing the resource utilization of the process wastewater; (2) The process water can be recycled without affecting the leaching rates of uranium and molybdenum; (3) More process water is recycled for the production process, the process water is recycled, reducing the consumption of natural water resources and also reducing the water use cost. Description of the Drawings

[0047] Figure 1 : Process flow chart.

[0048] Figure 2 : Flow chart of multi-stage and multi-level RO collaborative concentration and separation. Detailed Description of the Invention

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

[0050] Example 1

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

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

[0053] Step 2: Magnesium sulfate is added to the chemical dosing and stirring system 1, the pH is adjusted to 8 - 10 with sodium hydroxide, the stirring speed is controlled at 30 Hz - 50 Hz, and stirred for 10 min - 60 min. Then the stirring speed is adjusted to 5 Hz - 10 Hz and stirred for 5 min - 30 min, and then enters the asbestos plate frame filter. The operating pressure of the asbestos plate frame filter is 0.05 MPa - 0.2 MPa, and the filtrate enters the chemical dosing and stirring system 2;

[0054] Step 3: Sodium carbonate is added to the chemical dosing and stirring system 2, the pH is adjusted to 8 - 10 with sodium hydroxide, the stirring speed is controlled at 30 Hz - 50 Hz, and stirred for 10 min - 60 min. Then the stirring speed is adjusted to 5 Hz - 10 Hz and stirred for 5 min - 30 min, and then filtered through the amidoxime-modified polyacrylonitrile hollow fiber membrane for uranium extraction from seawater. The amidoxime-modified polyacrylonitrile hollow fiber membrane for uranium extraction from seawater performs suction solid-liquid separation in a negative pressure suction form, and the water produced by the amidoxime-modified polyacrylonitrile hollow fiber membrane for uranium extraction from seawater enters the chemical dosing and stirring system 3;

[0055] Step 4: Sulfuric acid is added to the chemical dosing and stirring system 3, the pH is adjusted to 6 - 7, the stirring speed is controlled at 30 Hz - 50 Hz, and stirred for 10 min - 60 min, and then enters the special resin for defluorination;

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

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

[0058] Step 7: Multi-stage and multi-level RO system: The process wastewater coming out of the softening resin enters the 1st stage and 1st level RO system. The 1st stage and 1st level RO system uses ordinary RO membranes, and the operating pressure is controlled at 1 MPa - 2.5 MPa, with a concentration of 2 - 4 times. The water produced by the 1st stage and 1st level RO system enters the 2nd level RO system. The 2nd level RO system uses ordinary RO membranes, and the operating pressure is controlled at 0.8 MPa - 1.5 MPa, with a concentration of 1 - 3 times. The water produced by the 2nd level RO system enters the 3rd level RO system. The 3rd level RO system uses ordinary RO membranes, and the operating pressure is controlled at 0.7 MPa - 1.2 MPa, with a concentration of 3 times. The water produced by the 3rd level RO system is recycled for the production process. The concentrated water of the 1st stage and 1st level RO system enters the 2nd stage RO system. The 2nd stage RO system uses ordinary RO membranes, and the operating pressure is controlled at 3 MPa - 5 MPa, with a concentration of 2 - 4 times. The water produced by the 2nd stage RO system, the water produced by the 1st stage and 1st level RO system, and the concentrated water of the 3rd level RO system are mixed and then enter the 2nd level RO system. The concentrated water of the 2nd stage RO system enters the 3rd stage RO system. The 3rd stage RO system uses high-pressure RO membranes, and the operating pressure is controlled at 6 MPa - 9 MPa, with a concentration of 2 - 4 times. The concentrated water of the 3rd stage RO system enters the 4th stage RO system. The 4th stage RO system uses ultra-high-pressure RO membranes, and the operating pressure is controlled at 10 MPa - 12 MPa, with a concentration of 0.5 - 1 times. The water produced by the 4th stage RO system, the water produced by the 3rd stage RO system, the concentrated water of the 2nd level RO system, and the process wastewater coming out of the softening resin are mixed and then enter the 1st stage and 1st level RO system. The concentrated water of the 4th stage RO system enters the extraction system;

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

[0060] Step 9: Potassium sulfate and sodium sulfate and other solid salts are obtained by multi-effect evaporation. The potassium sulfate and sodium sulfate and other solid salts are separated and purified through multiple crystallization. The condensed water from the multi-effect evaporation is recycled for the production process;

[0061] Technical description: This embodiment is for the process water to be recycled and not affect the leaching rates of uranium and molybdenum.

[0062] Example 2

[0063] This example 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 1. The differences are as follows: In step 1, the inlet water pressure of the manganese sand filter is controlled at 0.15 MPa; in step 2, magnesium sulfate is added to the dosing and stirring system 1, the pH is adjusted to 8.5 with sodium hydroxide, the stirring speed is controlled at 30 Hz and stirred for 30 min, then the stirring speed is adjusted to 10 Hz and stirred for 30 min, and then it enters the asbestos plate frame filter. The operating pressure of the asbestos plate frame filter is 0.1 MPa.

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

[0065] Example 3

[0066] This example 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 2. The differences are as follows: In step 3, sodium carbonate is added to the dosing and stirring system 2, the pH is adjusted to 10 with sodium hydroxide, the stirring speed is controlled at 45 Hz and stirred for 60 min, then the stirring speed is adjusted to 5 Hz and stirred for 30 min.

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

[0068] Example 4

[0069] This example 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. The differences are as follows: In step 4, sulfuric acid is added to the dosing and stirring system 3, the pH is adjusted to 6, the stirring speed is controlled at 50 Hz and stirred for 60 min.

[0070] Technical description: Sulfuric acid is added to the chemical dosing and mixing system 3 in Step 4 to adjust the pH to 6, and the stirring speed is controlled at 50 Hz for 60 minutes of stirring, in order to keep the process water slightly acidic and neutral, preparing for the removal of fluoride ions.

[0071] Example 5

[0072] This example is basically the same as the method for resource treatment of uranium-molybdenum ore acid oxygen pressure leaching process wastewater described in Example 4. The differences are as follows: In Step 5, the diameter of the resin tank for fluoride removal resin is controlled at 0.5 m, the height is controlled at 1.5 m, and the flow rate is controlled at 3 m / s.

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

[0074] Example 6

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

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

[0077] Example 7

[0078] This example is basically the same as the method for resource treatment of uranium-molybdenum ore acid oxygen pressure leaching process wastewater described in Example 1. The differences are as follows: In Step 7, the 1st stage and 1st level RO system uses a common RO membrane, with the operating pressure controlled at 2.5 MPa for 3 times of concentration. The water produced by the 1st stage and 1st level RO system enters the 2nd level RO system. The 2nd level RO system uses a common RO membrane, with the operating pressure controlled at 1.5 MPa for 1 time of concentration. The water produced by the 2nd level RO system enters the 3rd level RO system. The 3rd level RO system uses a common RO membrane, with the operating pressure controlled at 1 MPa for 3 times of concentration. The water produced by the 3rd level RO system is recycled for the production process.

[0079] Technical description: In step 7, the 1st stage and 1st pass RO system uses a common RO membrane, with the operating pressure controlled at 2.5 MPa and a concentration factor of 3. The product water of the 1st stage and 1st pass RO system enters the 2nd stage RO system. The 2nd stage RO system uses a common RO membrane, with the operating pressure controlled at 1.5 MPa and a concentration factor of 1. The product water of the 2nd stage RO system enters the 3rd stage RO system. The 3rd stage RO system uses a common RO membrane, with the operating pressure controlled at 1 MPa and a concentration factor of 3. The product water of the 3rd stage RO system is recycled for the production process, so as to enable the process water to be recycled for the production process without affecting the leaching rates of uranium and molybdenum.

[0080] Example 8

[0081] This example is basically the same as the method for resource treatment of waste water from the acid pressure leaching process of uranium molybdenum ore described in Example 7. The difference lies in that: in step 7, the concentrated water of the 1st stage and 1st pass RO system enters the 2nd stage RO system. The 2nd stage RO system uses a common RO membrane, with the operating pressure controlled at 5 MPa and a concentration factor of 3. The product water of the 2nd stage RO system, the product water of the 1st stage and 1st pass RO system, and the concentrated water of the 3rd stage RO system are mixed and then 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 uses a high-pressure RO membrane, with the operating pressure controlled at 8 MPa and a concentration factor of 3. The concentrated water of the 3rd stage RO system enters the 4th stage RO system.

[0082] Technical description: In step 7, the concentrated water of the 1st stage and 1st pass RO system enters the 2nd stage RO system. The 2nd stage RO system uses a common RO membrane, with the operating pressure controlled at 5 MPa and a concentration factor of 3. The product water of the 2nd stage RO system, the product water of the 1st stage and 1st pass RO system, and the concentrated water of the 3rd stage RO system are mixed and then 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 uses a high-pressure RO membrane, with the operating pressure controlled at 8 MPa and a concentration factor of 3. The concentrated water of the 3rd stage RO system enters the 4th stage RO system, so as to gradually increase the contents of molybdenum and salts and reduce energy consumption.

[0083] Example 9

[0084] This example is basically the same as the method for resource treatment of waste water from the acid pressure leaching process of uranium molybdenum ore described in Example 8. The difference lies in that: in step 7, the 4th stage RO system uses an ultra-high-pressure RO membrane, with the operating pressure controlled at 12 MPa and a concentration factor of 0.5. The product water of the 4th stage RO system, the product water of the 3rd stage RO system, the concentrated water of the 2nd stage RO system, and the process waste water from the softening resin are mixed and then enter the 1st stage and 1st pass RO system. The concentrated water of the 4th stage RO system enters the extraction system.

[0085] Technical description: In step 7, the 4-stage RO system uses ultra-high pressure RO membranes, with the operating pressure controlled at 12 MPa and the concentration factor at 0.5. The product water of the 4-stage RO system, the product 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 then enter the 1st stage and 1st level RO system. The concentrated water of the 4-stage RO system enters the extraction system to further increase the content of molybdenum and salts, preparing for the extraction and multi-effect evaporation of molybdenum.

[0086] Example 10

[0087] 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 Embodiment 1. The differences are as follows: In Step 1, the inlet pressure of the manganese sand filter is controlled at 0.1 MPa; in Step 2, magnesium sulfate is added to the dosing and stirring system 1, the pH is adjusted to 10 with sodium hydroxide, the stirring speed is controlled at 50 Hz, and stirred for 10 min. Then the stirring speed is adjusted to 5 Hz and stirred for 5 min, and then it enters the asbestos plate frame filter. The operating pressure of the asbestos plate frame filter is 0.2 MPa, and the filtrate enters the dosing and stirring system 2; in Step 3, sodium carbonate is added to the dosing and stirring system 2, the pH is adjusted to 10 with sodium hydroxide, the stirring speed is controlled at 50 Hz, and stirred for 60 min. Then the stirring speed is adjusted to 10 Hz and stirred for 5 min; in Step 4, sulfuric acid is added to the dosing and stirring system 3, the pH is adjusted to 6.5, the stirring speed is controlled at 50 Hz, and stirred for 60 min, and then it enters the special resin for defluorination; in Step 5, the diameter of the resin tank of the special resin for defluorination is controlled at 0.5 m, the height is controlled at 1.5 m, the flow rate is controlled at 2 m / s, and the process wastewater coming out of the special resin for defluorination enters the softening resin; in Step 6, the diameter of the resin tank of the softening resin is controlled at 1 m, the height is controlled at 2 m, the flow rate is controlled at 4 m / s, and the process wastewater coming out of the softening resin enters the multi-stage and multi-level RO system; in Step 7, the process wastewater coming out of the softening resin enters the 1st stage and 1st level RO system. The 1st stage and 1st level RO system uses a common RO membrane, the operating pressure is controlled at 2.5 MPa, and concentrated by 4 times. The water produced by the 1st stage and 1st level RO system enters the 2nd level RO system. The 2nd level RO system uses a common RO membrane, the operating pressure is controlled at 1.5 MPa, and concentrated by 3 times. The water produced by the 2nd level RO system enters the 3rd level RO system. The 3rd level RO system uses a common RO membrane, the operating pressure is controlled at 0.7 MPa, and concentrated by 3 times. The water produced by the 3rd level RO system is recycled for the production process. The concentrated water of the 1st stage and 1st level RO system enters the 2nd stage RO system. The 2nd stage RO system uses a common RO membrane, the operating pressure is controlled at 5 MPa, and concentrated by 2 times. The water produced by the 2nd stage RO system, the water produced by the 1st stage and 1st level RO system, and the concentrated water of the 3rd level RO system are mixed and then enter the 2nd level RO system. The concentrated water of the 2nd stage RO system enters the 3rd stage RO system. The 3rd stage RO system uses a high-pressure RO membrane, the operating pressure is controlled at 9 MPa, and concentrated by 4 times. The concentrated water of the 3rd stage RO system enters the 4th stage RO system. The 4th stage RO system uses an ultra-high-pressure RO membrane, the operating pressure is controlled at 12 MPa, and concentrated by 1 time. The water produced by the 4th stage RO system, the water produced by the 3rd stage RO system, the concentrated water of the 2nd level RO system, and the process wastewater coming out of the softening resin are mixed and then enter the 1st stage and 1st level RO system. The concentrated water of the 4th stage RO system enters the extraction system; in Step 8, extraction is carried out in the extraction system. The process wastewater coming from the extraction system enters the adsorption system. The adsorption system uses specific fibers for adsorption. The loading diameter of the specific fibers is controlled at 1 m, the height is controlled at 3 m, and the flow rate is controlled at 0.5 m / s. The process wastewater coming out of the special fiber enters multi-effect evaporation. In step 9, solid salts such as potassium sulfate and sodium sulfate are obtained through multi-effect evaporation. The solid salts such as potassium sulfate and sodium sulfate are separated and purified through multiple crystallizations, and the multi-effect evaporation condensate water is recycled for the production process.

[0088] Technical description: Adjusting the operation parameters and processes in steps 1-9 is to enable the recycling of process water without affecting the leaching rates of uranium and molybdenum.

Claims

1. A method for resource treatment of wastewater from the acid oxygen pressure leaching process of uranium molybdenum ore, comprising the following steps: Step 1: Process water enters a manganese sand filter. The manganese sand filter is made of fiberglass and is controlled by an automatic multi-way valve. The inlet water pressure is controlled at 0.1 MPa - 0.3 MPa, and the permeate enters the chemical dosing and stirring system 1; Step 2: Magnesium sulfate is added to the chemical dosing and stirring system 1, and the pH is adjusted to 8 - 10 with sodium hydroxide. The stirring speed is controlled at 30 Hz - 50 Hz and stirred for 10 min - 60 min, then the stirring speed is adjusted to 5 Hz - 10 Hz and stirred for 5 min - 30 min, and then it enters an asbestos plate frame filter. The operating pressure of the asbestos plate frame filter is 0.05 MPa - 0.2 MPa, and the filtrate enters the chemical dosing and stirring system 2; Step 3: Sodium carbonate is added to the chemical dosing and stirring system 2, and the pH is adjusted to 8 - 10 with sodium hydroxide. The stirring speed is controlled at 30 Hz - 50 Hz and stirred for 10 min - 60 min, then the stirring speed is adjusted to 5 Hz - 10 Hz and stirred for 5 min - 30 min, and then it is filtered through an amidoxime-modified polyacrylonitrile hollow fiber membrane for uranium extraction from seawater. The amidoxime-modified polyacrylonitrile hollow fiber membrane for uranium extraction from seawater uses a negative pressure suction form for solid-liquid separation, and the water produced by the amidoxime-modified polyacrylonitrile hollow fiber membrane for uranium extraction from seawater enters the chemical dosing and stirring system 3; Step 4: Sulfuric acid is added to the chemical dosing and stirring system 3, and the pH is adjusted to 6 - 7. The stirring speed is controlled at 30 Hz - 50 Hz and stirred for 10 min - 60 min, and then it enters a special resin for defluorination; Step 5: The diameter of the resin tank of the special resin for defluorination is controlled at 0.5 m - 1 m, the height is controlled at 1 m - 2 m, and the flow rate is controlled at 0.5 m / s - 5 m / s. The process wastewater coming out of the special resin for defluorination enters the softening resin; Step 6: The diameter of the resin tank of the softening resin is controlled at 0.5 m - 1 m, the height is controlled at 1 m - 2 m, and the flow rate is controlled at 0.5 m / s - 5 m / s. The process wastewater coming out of the softening resin enters a multi-stage and multi-level RO system; Step 7: Multi-stage and multi-level RO system: The process wastewater coming out of the softening resin enters the 1st-stage and 1st-level RO system. The 1st-stage and 1st-level RO system uses ordinary RO membranes, with the operating pressure controlled at 1 MPa - 2.5 MPa, and the concentration factor is 2 - 4 times. The water produced by the 1st-stage and 1st-level RO system enters the 2nd-level RO system. The 2nd-level RO system uses ordinary RO membranes, with the operating pressure controlled at 0.8 MPa - 1.5 MPa, and the concentration factor is 1 - 3 times. The water produced by the 2nd-level RO system enters the 3rd-level RO system. The 3rd-level RO system uses ordinary RO membranes, with the operating pressure controlled at 0.7 MPa - 1.2 MPa, and the concentration factor is 3 times. The water produced by the 3rd-level RO system is reused in the production process. The concentrated water of the 1st-stage and 1st-level RO system enters the 2nd-stage RO system. The 2nd-stage RO system uses ordinary RO membranes, with the operating pressure controlled at 3 MPa - 5 MPa, and the concentration factor is 2 - 4 times. The water produced by the 2nd-stage RO system, the water produced by the 1st-stage and 1st-level RO system, and the concentrated water of the 3rd-level RO system are mixed and then enter the 2nd-level RO system. The concentrated water of the 2nd-stage RO system enters the 3rd-stage RO system. The 3rd-stage RO system uses high-pressure RO membranes, with the operating pressure controlled at 6 MPa - 9 MPa, and the concentration factor is 2 - 4 times. The concentrated water of the 3rd-stage RO system enters the 4th-stage RO system. The 4th-stage RO system uses ultra-high-pressure RO membranes, with the operating pressure controlled at 10 MPa - 12 MPa, and the concentration factor is 0.5 - 1 times. The water produced by the 4th-stage RO system, the water produced by the 3rd-stage RO system, the concentrated water of the 2nd-level RO system, and the process wastewater coming out of the softening resin are mixed and then enter the 1st-stage and 1st-level RO system. The concentrated water of the 4th-stage RO system enters the extraction system; Step 8: The extraction system conducts extraction to recover molybdenum. The process wastewater coming out of the extraction system enters the adsorption system. The adsorption system uses specific fibers for adsorption, with the loading diameter of the specific fibers controlled at 0.2 m - 1 m, the height controlled at 1 m - 5 m, and the flow rate controlled at 0.5 m / s - 4 m / s. The process wastewater coming out of the specific fibers enters the multi-effect evaporation; Step 9: Potassium sulfate and sodium sulfate solid salts are obtained through multi-effect evaporation. The potassium sulfate and sodium sulfate solid salts are separated and purified through multiple crystallization. The condensed water from the multi-effect evaporation is reused in the production process.

2. The resource treatment method for the wastewater from the acid oxygen pressure leaching process of uranium molybdenum ore as claimed in claim 1, wherein: In Step 7, the 1st-stage and 1st-level RO system uses ordinary RO membranes, with the operating pressure controlled at 2.5 MPa, and the concentration factor is 3 times. The water produced by the 1st-stage and 1st-level RO system enters the 2nd-level RO system. The 2nd-level RO system uses ordinary RO membranes, with the operating pressure controlled at 1.5 MPa, and the concentration factor is 1 time. The water produced by the 2nd-level RO system enters the 3rd-level RO system. The 3rd-level RO system uses ordinary RO membranes, with the operating pressure controlled at 1 MPa, and the concentration factor is 3 times. The water produced by the 3rd-level RO system is reused in the production process.

3. The resource treatment method for the wastewater from the uranium-molybdenum ore acid oxygen pressure leaching process according to claim 2, characterized in that: In Step 7, the concentrated water of the 1st-stage and 1st-level RO system enters the 2nd-stage RO system. The 2nd-stage RO system uses ordinary RO membranes, with the operating pressure controlled at 5 MPa, and the concentration factor is 3 times. The water produced by the 2nd-stage RO system, the water produced by the 1st-stage and 1st-level RO system, and the concentrated water of the 3rd-level RO system are mixed and then enter the 2nd-level RO system. The concentrated water of the 2nd-stage RO system enters the 3rd-stage RO system. The 3rd-stage RO system uses high-pressure RO membranes, with the operating pressure controlled at 8 MPa, and the concentration factor is 3 times. The concentrated water of the 3rd-stage RO system enters the 4th-stage RO system.

4. The method for resource treatment of wastewater from the uranium-molybdenum ore acid oxygen pressure leaching process according to claim 3, characterized in that: In step 7, the four-stage RO system uses ultra-high pressure RO membranes, controls the operating pressure at 12 MPa, and concentrates by 0.5 times. The water produced by the four-stage RO system, the water produced by the three-stage RO system, the concentrated water of the two-stage RO system, and the process wastewater from the softened resin are mixed and then enter the first-stage and first-level RO system. The concentrated water of the four-stage RO system enters the extraction system.

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

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