Device and method for efficiently removing oil from raffinate in molybdenum ore hydrometallurgy process

Abstract

The invention discloses a device and a method for efficiently removing oil from raffinate in a molybdenum ore hydrometallurgy process, and relates to the technical field of hydrometallurgy. The oil removal method comprises the following steps: measuring the oxidation-reduction potential Eh and the oil content of the raffinate; adjusting the redox potential Eh of the raffinate to be less than or equal to 450mV; h2O2 is added into the raffinate, and a constant-temperature stirring reaction is carried out; and when the oil content in the raffinate is detected to be less than 10mg / L through sampling, starting a liquid discharge pump, filtering the reacted raffinate through a bag filter, and discharging the filtered raffinate to a storage pool. The oil removal method provided by the invention is short in treatment flow, low in reagent consumption, high in oil removal efficiency and beneficial to industrial application. The oil removal device provided by the invention mainly comprises a raffinate feeding tank, a reactor, an iron agent dosing system, an H2O2 dosing system, a liquid discharge system, a bag filter and a storage pool. And through online monitoring feedback, automation and continuity of the efficient oil removal process of the raffinate water in the molybdenum ore hydrometallurgy process are realized.

Description

Technical Field

[0001] The present invention relates to the technical field of hydrometallurgy, and in particular to a device and method for efficiently removing oil from raffinate water during the hydrometallurgical process of molybdenum ore. Background Art

[0002] Due to its excellent physical, chemical, and mechanical properties, molybdenum, both as a single element and in its alloys, has broad applications and promising development prospects in key sectors such as metallurgy, agriculture, electrical engineering, chemical engineering, environmental protection, and aerospace. It also holds particular application value in defense, military, and nuclear industries, making it a crucial strategic resource. During the hydrometallurgical smelting of molybdenum minerals, extraction processes are commonly used to separate and recover molybdenum from the leachate. The raffinate contains not only molybdenum, iron, silicon, calcium, phosphorus, and sulfur, but also excess sulfuric acid and a small amount of organic phase (oil). This oil primarily originates from extractants, modifiers, and diluents such as trioctyldecyl tertiary amine, di(2-ethylhexyl) phosphate, tributyl phosphate, and kerosene. The presence of oil can lead to the following problems during the reuse of the raffinate: 1) When using the residual acid in the raffinate for preleaching, the oil film adsorbs mineral powder and floats on the slurry surface. This agitation generates a large amount of foam, which expands the slurry volume and causes "bubbling." 2) Using the raffinate to wash the filter cake slows filtration and results in poor washing results. The current extraction process oil removal technologies mainly include ultrasonic flotation, fiber ball filtration, inclined plate oil separation, activated carbon adsorption, resin adsorption and oxidation, etc., which use physical and chemical means to adsorb, separate, enrich and decompose the oil in the aqueous phase during the extraction process.

[0003] The oil removal methods used in the prior art and the problems therein are: 1) lime is used in production to neutralize the raffinate water to a pH of 7-8, and then activated carbon is used for adsorption and oil removal, so that the oil content in the water is controlled below 10 mg / L. This method seriously affects the recycling of process water and waste acid, causing both reagent waste and potential safety hazards; 2) the oil-containing aqueous phase is treated with a coalescing filter element and then enters an oil-water separator for oil-water separation. The separated dissolved oil solution is subjected to adsorption and oil removal by a macroporous adsorption-type oil removal resin. This method is mainly suitable for the degreasing process of high-value solutions such as product liquids. The oil removal resin needs to be resolved using 3 BV of ammonia water and 2 BV of The residual ammonia in the resin is replaced by clean water, which has the problems of high treatment cost, large amount of wastewater, poor operating environment, etc.; 3) The raffinate is sequentially subjected to a multi-stage combined treatment process such as medium-temperature gas flotation coalescence, high-temperature steam demulsification, high-temperature steam-low-temperature air metal fiber coalescence filtration, and activated carbon adsorption for oil removal. This method requires heating and cooling the raffinate during the treatment process. The high-temperature steam temperature is 115℃~450℃, the medium-temperature circulating exhaust gas temperature is 45℃~115℃, and the low-temperature air temperature is -25℃~32℃. The temperature change range is large, the equipment requirements are high, the energy consumption is large, and the treatment cost is high; 4) The raffinate is sequentially subjected to a clarification tank for standing, dissolved air flotation, 5) Degreasing the raffinate by a combination of processes such as persulfate advanced oxidation. This method introduces sodium ions during the oxidation and decomposition of organic matter using sodium persulfate. The increase in the concentration of monovalent cations will reduce the leaching rate of molybdenum, which is not conducive to the reuse of the raffinate water. 5) Degreasing the raffinate by a combination of processes such as centrifugal or ultrasonic oscillation physical means of demulsification, kerosene capture, clarification, precision filtration, fiber adsorption, and activated carbon adsorption. This method involves many degreasing devices, a complex and lengthy treatment process, low treatment efficiency, and is not suitable for industrial application. 6) Degreasing the raffinate by ozone catalytic oxidation-sodium hypochlorite secondary oxidation. This method requires the use of ozone and sodium hypochlorite, is highly irritating, has a poor manual operating environment, and has a safety system. The number is low; the oxidizing property is strong and chloride ions are introduced at the same time, which has high requirements for equipment and a small scope of application; 7) the finished extract liquid is subjected to a process of standing oil separation, nano-bubble flotation, ultrasonic demulsification, ozone oxidation, etc. for deep deoiling. This method has high deoiling efficiency, but the process is long and the processing cost is high. It is suitable for treating finished liquid and is not suitable for a large amount of raffinate water; 8) the raffinate is subjected to a process of natural clarification, flotation, ultrasonic demulsification, activated carbon adsorption, etc. for deoiling, and then reused after neutralization with calcium hydroxide. This method has a complex raffinate deoiling process and produces a large amount of oil-containing activated carbon, which poses a safety hazard; the neutralization process introduces a large amount of calcium ions, which are prone to scaling in the system after reuse; the reagent material consumption is large and the processing cost is high.

[0004] Therefore, there is an urgent need to provide a device and method for efficiently removing oil from the residual water in the molybdenum ore hydrometallurgy process to solve the problems existing in the prior art. Summary of the Invention

[0005] In view of the limitations of the existing technology, the purpose of the present invention is to provide a device and method for efficiently removing oil from the extract water during the molybdenum ore hydrometallurgy process, aiming to solve the problems in the existing technology such as complex and lengthy treatment process, high equipment requirements, poor operating environment, low treatment efficiency, large consumption of reagents and materials, generation of a large amount of oil-containing waste, high treatment cost, poor solution reusability, and being unfavorable for industrial application.

[0006] To achieve the above-mentioned object of the invention, the technical solution adopted by the present invention is: a method for efficiently removing oil from raffinate water in a molybdenum ore hydrometallurgy process, comprising the following steps:

[0007] Determination: Measure the redox potential Eh and oil content of the raffinate water; when the redox potential Eh of the raffinate water is ≤450mV, skip the adjustment step and directly enter the dosing reaction step; when the redox potential Eh of the raffinate water is >450mV, enter the adjustment step;

[0008] Adjustment: Start stirring and add iron to the raffinate water through the iron dosing system until the redox potential of the raffinate water Eh ≤ 450mV;

[0009] Dosing reaction: add H2O2 to the raffinate water through the H2O2 dosing system and stir the reaction at a constant temperature;

[0010] Detection: Detect the oil content in the raffinate water after the dosing reaction. When the oil content is less than 10 mg / L, turn on the drainage pump, filter the raffinate water after the reaction through a bag filter, and then discharge it to the storage tank.

[0011] Furthermore, the redox potential Eh of the raffinate water is adjusted to be between 360 mV and 440 mV.

[0012] Furthermore, the iron agent includes iron powder, iron filings or ferrous sulfate.

[0013] Furthermore, H2O2 is an H2O2 solution with a mass percentage concentration of 20% to 40%.

[0014] Furthermore, the amount of H2O2 added is 7 mL to 12 mL H2O2 per 100 mg of oil.

[0015] Further, after adding H2O2, the reaction was stirred at a constant temperature of 60°C to 80°C for 5min to 60min.

[0016] Furthermore, the raffinate water comes from the raffinate water in the molybdenum ore hydrometallurgy process.

[0017] Furthermore, the raffinate water contains sulfuric acid, molybdenum, iron, oil and trace elements; the trace elements include one or more of uranium, silicon, calcium, phosphorus, sulfur and arsenic; the oil includes one or more of trioctyldecyl tertiary amine, di(2-ethylhexyl) phosphate, tributyl phosphate and kerosene.

[0018] Furthermore, in the raffinate water, the sulfuric acid concentration is 5g / L to 50g / L, the ΣFe content is 1g / L to 10g / L, and the oil content is ≤200mg / L.

[0019] A device for efficiently removing oil from raffinate water during molybdenum ore hydrometallurgy is disclosed. The device is used in the above-mentioned method for efficiently removing oil from raffinate water during molybdenum ore hydrometallurgy. The device comprises a raffinate water feeding trough, a reactor, an iron agent dosing system, an H2O2 dosing system, a drainage system, a bag filter and a storage tank. The reactor main body is a constant temperature stirring tank equipped with a liquid inlet, a liquid outlet, a sampling port, a constant temperature heating device, an online temperature monitoring system, an online redox potential monitoring system, a variable frequency adjustable speed mechanical stirring device, a liquid level meter and a dosing port.

[0020] Compared with the prior art, the present invention has at least the following beneficial effects:

[0021] The oil removal method for extracting raffinate water from a molybdenum ore hydrometallurgy process provided by the present invention has the advantages of a simple and continuous treatment process, environmentally friendly reagents, low reagent consumption, low treatment cost, high oil removal efficiency, good oil removal effect, no introduction of other impurity ions, a friendly operating environment, environmental protection, conducive to industrial application, and minimal impact on the original process system. The oil removal method provided by the present invention is applied to the efficient oil removal process of extracting raffinate water from a molybdenum ore hydrometallurgy process. The oil content in the extracting raffinate water after treatment is less than 10 mg / L, which can meet the process water reuse requirements of the molybdenum ore hydrometallurgy process. The present invention uses a reactor to automatically perform extracting raffinate water oil removal treatment, has an online monitoring function, a high degree of automation, can operate continuously, and has high treatment efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0023] Figure 1 The present invention provides an apparatus for efficiently removing oil from raffinate water during the hydrometallurgical process of molybdenum ore. DETAILED DESCRIPTION

[0024] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only some of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative efforts shall fall within the scope of protection of the present invention.

[0025] A first aspect of the present invention provides a method for efficiently removing oil from raffinate water during a molybdenum ore hydrometallurgy process, comprising the following steps:

[0026] Step 1: Determination

[0027] Measure the redox potential Eh and Fe of the raffinate water 2+ concentration and oil content; when the redox potential Eh of the raffinate water is ≤450mV, the second adjustment step can be skipped and the third dosing reaction step can be directly entered; when the redox potential Eh of the raffinate water is >450mV, the adjustment step can be entered;

[0028] Step 2: Adjustment

[0029] Start stirring and add iron to the raffinate water through the iron dosing system until the redox potential of the raffinate water Eh ≤ 450mV;

[0030] Step 3: Dosing reaction

[0031] According to the oil content in the raffinate water, H2O2 is added to the raffinate water through the H2O2 dosing system and stirred at a constant temperature for reaction;

[0032] Step 4: Detection

[0033] Detect the oil content in the raffinate water after the dosing reaction. When the oil content is less than 10 mg / L, start the drainage pump, filter the raffinate water after the reaction through a bag filter, and then discharge it into the storage tank.

[0034] The oil removal method provided by the present invention uses hydrogen peroxide and iron to oxidatively decompose the oil in raffinate water, resulting in a short, rapid, and efficient process. By adjusting the redox potential (Eh) of the raffinate water to determine the addition of iron and H2O2, and by rationally adding reagents, this method not only reduces reagent consumption and significantly lowers material processing costs, but also achieves high treatment efficiency. The oil content in the raffinate water after treatment is significantly reduced to less than 10 mg / L, meeting the requirements for process water reuse in molybdenum ore hydrometallurgy.

[0035] In some feasible embodiments, the redox potential Eh of the raffinate water is adjusted to be between 360 mV and 440 mV.

[0036] Specifically, the redox potential Eh of the raffinate water is adjusted to be between 360mV and 440mV by adding iron agent, so that Fe2+ The concentration is between 0.5g / L and 5g / L. 2+ It acts as a catalyst. If the content is too low, the reaction speed will be too slow and the efficient purpose cannot be achieved. If the content is too high, although it can promote the reaction, the efficiency increase is not very large, but it will cause an increase in the amount of iron agent used, wasting resources. From the perspective of reaction speed and resource conservation, the present invention preferably adjusts the redox potential Eh of the raffinate water to between 360mV and 440mV, and most preferably adjusts the redox potential Eh of the raffinate water to between 380mV and 420mV.

[0037] In some feasible embodiments, the iron agent includes iron powder, iron filings, or ferrous sulfate.

[0038] Specifically, by adding iron powder, iron filings or ferrous sulfate, the Fe 2+ The presence of a small amount of Fe 2+ It can start the reaction and act as a catalyst.

[0039] In some feasible implementations, H2O2 is an H2O2 solution with a mass percentage concentration of 20% to 40%.

[0040] Specifically, the H2O2 concentration is directly related to the dosage and reaction rate. When the H2O2 concentration is too low, the reaction rate is slow and the dosage required is high. When the H2O2 concentration is too high, local side reactions are likely to occur, the reaction process is violent, and large amounts of gas may be generated, even causing explosions. 30% H2O2 is most preferred in the present invention.

[0041] In some feasible embodiments, the amount of H2O2 added is 7 mL to 12 mL H2O2 per 100 mg of oil.

[0042] Specifically, H2O2 reacts with Fe 2+ The reaction occurs, generating hydroxyl radicals, which then oxidize and degrade the organic matter (oil). When the amount of H2O2 added is small, the reaction rate is slow, the organic matter is not fully oxidized, and the oil in the aqueous phase cannot be completely removed. When the amount of H2O2 added is too large, the reaction is violent, and H2O2 directly decomposes, inhibiting the generation of hydroxyl radicals, reducing the oil removal efficiency of the rectification process, posing a safety risk, and also resulting in a huge waste of reagents. Therefore, the preferred amount of H2O2 added in the present invention is 7mL to 12mL of H2O2 for every 100mg of oil.

[0043] In some feasible embodiments, after adding H2O2, the reaction is stirred at a constant temperature of 60°C to 80°C for 5 minutes to 60 minutes.

[0044] Specifically, temperature has a significant impact on the rate of chemical reactions. When the temperature is too low, the reaction rate is slow, reducing oil removal efficiency. When the temperature is too high, H₂O₂ decomposes directly and accelerates the consumption of hydroxyl radicals, leading to increased reagent consumption and reduced oil removal efficiency. The preferred temperature for this invention is 60°C to 80°C.

[0045] In some feasible embodiments, the raffinate water comes from the raffinate water in the molybdenum ore hydrometallurgy process.

[0046] Specifically, during the molybdenum extraction process from molybdenum ore hydrometallurgy, extractants, modifiers, and diluents are required. Consequently, the composition of the raffinate water is complex and contains a large amount of oil. During the reuse process, the slurry volume expands, causing "bubbling" and slowing the filtration rate when the raffinate water is used to wash the slurry filter cake. The oil content in the raffinate water treated by the method of the present invention is significantly reduced to <10 mg / L, meeting the process water reuse requirements of the molybdenum ore hydrometallurgy process. Furthermore, the method of the present invention utilizes environmentally friendly reagents, significantly improving the reusability of the raffinate water in the molybdenum ore hydrometallurgy process.

[0047] In some feasible embodiments, the raffinate water from the molybdenum ore hydrometallurgy process contains sulfuric acid, molybdenum, iron, oil and trace elements; wherein the trace elements include one or more of uranium, silicon, calcium, phosphorus, sulfur and arsenic; the oil includes one or more of trioctyldecyl tertiary amine, di(2-ethylhexyl) phosphate, tributyl phosphate and kerosene; the sulfuric acid concentration is 5g / L~50g / L, the ΣFe content is 1g / L~10g / L, and the oil content is ≤200mg / L.

[0048] Specifically, for the raffinate water from the molybdenum ore hydrometallurgy process, the oil content in the raffinate water treated by the method of the present invention is significantly reduced to <10 mg / L, and no other impurity ions are introduced. The raffinate water after oil removal can be returned to the prepreg tank through the production system for use as slurry prepreg pulping, and the residual acid therein can be utilized to reduce the amount of sulfuric acid used in the leaching process; it can also be returned to the solid-liquid separation washing process to wash the filter cake, saving resources and greatly reducing the production cost of the enterprise.

[0049] A second aspect of an embodiment of the present invention provides a device for efficiently removing oil from raffinate water during molybdenum ore hydrometallurgy, which is used for the above-mentioned method for efficiently removing oil from raffinate water during molybdenum ore hydrometallurgy, and includes a raffinate water feeding trough, a reactor, an iron agent dosing system, an H2O2 dosing system, a drainage system, a bag filter and a storage tank; the reactor main body device is a constant temperature stirring tank, equipped with a liquid inlet, a liquid outlet, a sampling port, a constant temperature heating device, an online temperature monitoring system, an online redox potential monitoring system, a variable frequency adjustable speed mechanical stirring device, a liquid level meter and a dosing port.

[0050] Specifically, the oil removal device provided by the present invention offers low processing costs, environmentally friendly operation, and minimal impact on existing process systems. The present invention utilizes a reactor to automatically remove oil from raffinate water, features online monitoring, and boasts a high degree of automation, continuous operation, and high processing efficiency. The oil removal device provided by the present invention offers advantages such as a simple and continuous processing process, high oil removal efficiency, excellent oil removal results, no impurities introduced, environmental friendliness, and suitability for industrial applications.

[0051] Example 1 Condition Screening (I) A Device for Efficiently Removing Oil from Raffinate Water During Molybdenum Ore Hydrometallurgy

[0052] like Figure 1 As shown, the device includes a raffinate feed tank, a reactor, an iron dosing system, an H2O2 dosing system, a drainage system, a bag filter, and a storage tank. The reactor body is a constant-temperature stirring tank equipped with a liquid inlet, a liquid outlet, a sampling port, a constant-temperature heating device, an online temperature monitoring system, an online redox potential monitoring system, a variable-frequency adjustable-speed mechanical stirring device, a liquid level gauge, and a dosing port.

[0053] The raffinate water enters the reactor from the liquid inlet through the feed trough. The main device of the reactor is a constant temperature stirring tank, which can perform continuous or intermittent raffinate water deoiling treatment. Iron powder, iron filings or ferrous sulfate and H2O2 are added to the reactor through the iron agent dosing system and the H2O2 dosing system respectively. After a period of constant temperature stirring reaction, samples are taken through the sampling port to detect the oil content of the raffinate water. When the oil content is less than 10 mg / L, the drainage pump is turned on, and the raffinate water after the dosing reaction is sent to the bag filter through the liquid outlet and drainage system for filtration, and then discharged to the storage tank for standby use. The raffinate water after deoiling can be returned to the prepreg tank through the production system for use as slurry pre-impregnation pulping or returned to the solid-liquid separation washing process to wash the filter cake.

[0054] (2) Condition screening

[0055] The main components of the extractant of a molybdenum ore processing enterprise are di(2-ethylhexyl) phosphate, tributyl phosphate and kerosene. The oil content in the raffinate water is 102.36 mg / L. The other main chemical components are: H2SO4 content is 23.51 g / L, Eh is 574 mV, ΣFe content is 1.26 g / L (Fe 2+ The content of sludge is 0.212 g / L), the content of Mo is 0.025 g / L, the content of P is 0.073 g / L, the content of Ca is 0.546 g / L, and the content of Si is 0.383 g / L. 1. The effect of the redox potential (Eh) of the raffinate water on oil removal

[0056] Use (1) oil removal device, the method is as follows:

[0057] Step 1: Feed

[0058] The feed pump is started to pump the raffinate water to be treated into the reactor. The volume of the raffinate water pumped in is less than or equal to 2 / 3 of the reactor volume, which is 3000 L in this embodiment.

[0059] Step 2: Adjustment

[0060] The reactor was mechanically stirred at 80 rpm, and the raffinate water to be treated was heated to 70° C. Ferrous sulfate was slowly added through the hopper to adjust the redox potential (Eh) of the raffinate water to 340 mV, 360 mV, 380 mV, 400 mV, 420 mV, 440 mV, and 460 mV, respectively. Stirring was continued for 20 minutes after the redox potential stabilized.

[0061] Step 3: Dosing reaction

[0062] 30.7 L of H2O2 with a mass percentage concentration of 30% was added through a dosing pump, the solution temperature in the reactor was maintained at 70°C, and stirred at constant temperature for 30 minutes.

[0063] Step 4: Detection

[0064] The raffinate water after the dosing reaction was sampled and analyzed to detect the oil content. The test results are shown in Table 1.

[0065] Table 1

[0066] Oxidation-reduction potential (Eh) Oil content 340mV 11.13mg / L 360mV 5.31mg / L 380mV 5.61mg / L 400mV 5.62mg / L 420mV 5.66mg / L 440mV 9.22mg / L 460mV 15.66mg / L

[0067] As can be seen from Table 1, under the same reaction time, temperature and H2O2 dosage conditions, the redox potential (Eh) of the raffinate water can meet the oil removal requirements in the range of 360mV to 440mV. When Eh ≥ 460mV, the oil removal efficiency is relatively reduced. This is because the low initial catalyst concentration reduces the reaction rate; when Eh ≤ 420mV, the oil removal efficiency does not change significantly with the decrease of Eh. When Eh ≤ 340mV, the excess catalyst causes part of the H2O2 to directly decompose, reducing the reagent utilization rate and the oil removal effect. In order to reduce the cost of reagent consumption, the present invention preferably adjusts the Eh range to 360mV to 440mV, and more preferably adjusts the Eh range to 380mV to 420mV.

[0068] 2. Effect of H2O2 concentration on oil removal

[0069] Use (1) oil removal device, the method is as follows:

[0070] Step 1: Feed

[0071] The feed pump is started to pump the raffinate water to be treated into the reactor. The volume of the raffinate water pumped in is less than or equal to 2 / 3 of the reactor volume, which is 3000 L in this embodiment.

[0072] Step 2: Adjustment

[0073] The reactor was mechanically stirred at 80 rpm, and the raffinate water to be treated was heated to 70° C. Ferrous sulfate was slowly added through the hopper to adjust the redox potential (Eh) of the raffinate water to 400 mV. After the redox potential stabilized, stirring was continued for 20 minutes.

[0074] Step 3: Dosing reaction

[0075] 30.7 L of H2O2 with mass percentage concentrations of 10%, 20%, 30%, 40% and 50% were added through a dosing pump, the solution temperature in the reactor was maintained at 70°C, and stirred at constant temperature for 30 minutes.

[0076] Step 4: Detection

[0077] The raffinate water after the dosing reaction was sampled and analyzed to detect the oil content. The test results are shown in Table 2.

[0078] Table 2

[0079] <![CDATA[Concentration of H2O2]]> Oil content 10％ 35.41mg / L 20％ 20.13mg / L 30％ 5.62mg / L 40％ 4.35mg / L 50％ 5.82mg / L

[0080] As can be seen from Table 2, when the H2O2 concentration is less than 30%, the oil removal effect is not ideal. This is because the H2O2 concentration is too low and the effective ingredients cannot meet the oil removal requirements under the same dosage conditions. When the H2O2 concentration is ≥30%, the oil content can meet the requirement of oil content less than 10 mg / L after oil removal. The oil removal effect does not change significantly with the increase of H2O2 concentration. Since excessively high concentrations of H2O2 will self-decompose or induce side reactions during the process, in order to save reagent consumption and safety considerations, 30% to 40% H2O2 is most preferred in the present invention.

[0081] 3. Effect of H2O2 addition on oil removal

[0082] Use (1) oil removal device, the method is as follows:

[0083] Step 1: Feed

[0084] The feed pump is started to pump the raffinate water to be treated into the reactor. The volume of the raffinate water pumped in is less than or equal to 2 / 3 of the reactor volume, which is 3000 L in this embodiment.

[0085] Step 2: Adjustment

[0086] The reactor was mechanically stirred at 80 rpm, and the raffinate water to be treated was heated to 70° C. Ferrous sulfate was slowly added through the hopper to adjust the redox potential (Eh) of the raffinate water to 400 mV. After the redox potential stabilized, stirring was continued for 20 minutes.

[0087] Step 3: Dosing reaction

[0088] Add 18.4 L, 21.5 L, 24.6 L, 27.6 L, 30.7 L, 33.8 L, 36.8 L, and 40.0 L of H2O2 with a mass percentage concentration of 30% through a dosing pump, maintain the solution temperature in the reactor at 70°C, and stir at constant temperature for 30 minutes.

[0089] Step 4: Detection

[0090] The raffinate water after the dosing reaction was sampled and analyzed to detect the oil content. The test results are shown in Table 3.

[0091] Table 3

[0092] <![CDATA[Dosage of H2O2]]> <![CDATA[H2O2 dosage corresponding to every 100 mg of oil]]> Oil content 18.4L 6mL 15.32mg / L 21.5L 7mL 9.86mg / L 24.6L 8mL 7.17mg / L 27.6L 9mL 6.42mg / L 30.7L 10mL 5.62mg / L 33.8L 11mL 5.55mg / L 36.8L 12mL 4.43mg / L 40.0L 13mL 4.23mg / L

[0093] As shown in Table 3, when less than 7 mL of H₂O₂ is added per 100 mg of oil, the amount of H₂O₂ is insufficient to meet the oil removal requirements, and the oil removal effect falls short of production requirements. When ≥7 mL of H₂O₂ is added per 100 mg of oil, the oil content can be reduced to less than 10 mg / L after oil removal, and the oil removal effect improves with increasing H₂O₂ dosage. When ≥12 mL of H₂O₂ is added per 100 mg of oil, further increasing the H₂O₂ dosage results in a more gradual change in the oil removal effect. Considering the effects of other impurities and conserving reagent consumption, the present invention preferably adds 7 to 12 mL of H₂O₂ per 100 mg of oil.

[0094] 4. Effect of reaction temperature on oil removal

[0095] Use (1) oil removal device, the method is as follows:

[0096] Step 1: Feed

[0097] The feed pump is started to pump the raffinate water to be treated into the reactor. The volume of the raffinate water pumped in is less than or equal to 2 / 3 of the reactor volume, which is 3000 L in this embodiment.

[0098] Step 2: Adjustment

[0099] The reactor was mechanically stirred at 80 rpm, and the raffinate water to be treated was heated to 50°C, 60°C, 70°C, 80°C, and 90°C, respectively. Ferrous sulfate was slowly added through the hopper to adjust the redox potential (Eh) of the raffinate water to 400 mV. After the redox potential stabilized, stirring was continued for 20 minutes.

[0100] Step 3: Dosing reaction

[0101] 30.7 L of H2O2 with a mass percentage concentration of 30% was added through a dosing pump, and the solution temperatures in the reactor were maintained at 50°C, 60°C, 70°C, 80°C, and 90°C, respectively, and stirred at constant temperature for 30 minutes.

[0102] Step 4: Detection

[0103] The raffinate water after the dosing reaction was sampled and analyzed to detect the oil content. The test results are shown in Table 4.

[0104] Table 4

[0105] Reaction temperature Oil content 50℃ 42.37mg / L 60℃ 9.16mg / L 70℃ 5.62mg / L 80℃ 4.77mg / L 90℃ 12.31mg / L

[0106] As shown in Table 4, when the reaction temperature is ≤50°C, the chemical reaction rate decreases, and within the same reaction time, the oil content in the treated water cannot meet production requirements. When the reaction temperature is 60°C to 80°C, the chemical reaction rate increases with increasing reaction temperature, and the oil content in the treated water is consistently less than 10 mg / L, decreasing with increasing temperature. When the reaction temperature is ≥90°C, due to the excessively high temperature, some H2O2 directly decomposes, resulting in reagent waste and reduced oil treatment effectiveness in the water. Taking all factors into consideration, the preferred reaction temperature for the present invention is 60°C to 80°C.

[0107] Example 2: A device and method for efficiently removing oil from raffinate water during molybdenum ore hydrometallurgy

[0108] (1) A device for efficiently removing oil from residual water during the hydrometallurgical process of molybdenum ore

[0109] Same as Example 1.

[0110] (2) A method for efficiently removing oil from raffinate water during molybdenum ore hydrometallurgy

[0111] The main components of the extractant of a molybdenum ore processing enterprise are trioctyldecyl tertiary amine, tributyl phosphate and kerosene. The oil content of the raffinate water is 97.31 mg / L. Other main chemical components are: H2SO4 content is 21.42 g / L, Eh is 400 mV, ΣFe content is 5.98 g / L (including Fe 2+ The content of raw materials is 3.52g / L), the content of Mo is 0.022g / L, the content of U is 0.019g / L, the content of As is 0.222g / L, the content of P is 0.067g / L, the content of Ca is 0.679g / L, and the content of Si is 0.364g / L.

[0112] Use (1) oil removal device, the method is as follows:

[0113] Step 1: Feed

[0114] The feed pump is started to pump the raffinate water to be treated into the reactor. The volume of the raffinate water pumped in is less than or equal to 2 / 3 of the reactor volume, which is 5000 L in this embodiment.

[0115] Step 2: Dosing reaction

[0116] Start mechanical stirring in the reactor at 60 rpm and heat the raffinate to be treated to 60°C. Add 50.0 L of 30% H₂O₂ via a dosing pump. Maintain the solution temperature at 60°C and stir at this constant temperature for 40 minutes.

[0117] Step 3: Detection

[0118] After the dosing reaction, the raffinate water was sampled and analyzed, revealing an oil content of 6.81 mg / L. The drainage pump was activated, sending the raffinate water through the outlet and drainage system to a bag filter for filtration. The water was then discharged to a storage tank and reused through the process water circulation system.

[0119] Example 3: A device and method for efficiently removing oil from raffinate water during molybdenum ore hydrometallurgy

[0120] (1) A device for efficiently removing oil from residual water during the hydrometallurgical process of molybdenum ore

[0121] Same as Example 1.

[0122] (2) A method for efficiently removing oil from raffinate water during molybdenum ore hydrometallurgy

[0123] The main components of the extractant of a molybdenum ore processing enterprise are trioctyldecyl tertiary amine, di(2-ethylhexyl) phosphate, tributyl phosphate and kerosene. The oil content of the raffinate water is 36.26 mg / L. The other main chemical components are: H2SO4 content is 31.53 g / L, Eh is 380 mV, ΣFe content is 2.11 g / L (Fe 2+ The content of the raw materials is 1.32g / L), the content of Mo is 0.032g / L, the content of P is 0.088g / L, the content of Ca is 0.436g / L, and the content of Si is 0.213g / L.

[0124] The oil removal device of (1) is used as follows:

[0125] Step 1: Feed

[0126] The feed pump is started to pump the raffinate water to be treated into the reactor. The volume of the raffinate water pumped in is less than or equal to 2 / 3 of the reactor volume, which is 4000 L in this embodiment.

[0127] Step 2: Dosing reaction

[0128] The reactor was stirred mechanically at 70 rpm, and the raffinate to be treated was heated to 80° C. 11.0 L of 30% H2O2 was added via a dosing pump, maintaining the solution temperature at 80° C. and stirring at this constant temperature for 20 minutes.

[0129] Step 3: Detection

[0130] After the dosing reaction, the raffinate water was sampled and analyzed, revealing an oil content of 4.37 mg / L. The drainage pump was activated, sending the raffinate water through the outlet and drainage system to a bag filter for filtration before draining to a storage tank. The water was then recycled through the process water circulation system.

[0131] Example 4: A device and method for efficiently removing oil from raffinate water during molybdenum ore hydrometallurgy

[0132] (1) A device for efficiently removing oil from residual water during the hydrometallurgical process of molybdenum ore

[0133] Same as Example 1.

[0134] (2) A method for efficiently removing oil from raffinate water during molybdenum ore hydrometallurgy

[0135] The main components of the extractant of a molybdenum ore processing enterprise are di(2-ethylhexyl) phosphate, tributyl phosphate, and kerosene. The oil content in the raffinate water is 54.18 mg / L. The other main chemical components are: H2SO4 content is 41.22 g / L, Eh is 587 mV, ΣFe content is 4.28 g / L (Fe 2+ The content of the raw materials is 0.236g / L), the content of Mo is 0.042g / L, the content of P is 0.034g / L, the content of Ca is 0.511g / L, and the content of Si is 0.384g / L.

[0136] Use (1) oil removal device, the method is as follows:

[0137] Step 1: Feed

[0138] The feed pump is started to pump the raffinate water to be treated into the reactor. The volume of the raffinate water pumped in is less than or equal to 2 / 3 of the reactor volume, which is 6000 L in this embodiment.

[0139] Step 2: Adjustment

[0140] The reactor was stirred mechanically at 80 rpm, and the raffinate to be treated was heated to 70°C. Reduced iron powder was slowly added through the hopper to adjust the redox potential (Eh) of the raffinate to be treated to 400 mV (Fe 2+ The content was 1.73 g / L), and stirring was continued for 20 min after the redox potential was stabilized.

[0141] Step 3: Dosing reaction

[0142] 26.0 L of H2O2 with a mass percentage concentration of 30% was added through a dosing pump, the solution temperature in the reactor was maintained at 70°C, and stirred at constant temperature for 30 minutes.

[0143] Step 4: Detection

[0144] After the dosing reaction, the raffinate water was sampled and analyzed, revealing an oil content of 7.34 mg / L. The drainage pump was activated, sending the raffinate water through the outlet and drainage system to a bag filter for filtration before draining it to a storage tank. It was then reused through the process water circulation system.

[0145] It is easy for those skilled in the art to understand that, under the premise of no conflict, the above-mentioned advantageous methods can be freely combined and superimposed. The above is only a preferred embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent replacements and improvements made within the spirit and principles of the present application should be included in the scope of protection of the present application. The above is only a preferred embodiment of the present application. It should be pointed out that for ordinary technicians in this technical field, several improvements and variations can be made without departing from the technical principles of the present application. These improvements and variations should also be regarded as the scope of protection of the present application.

Claims

1. A method for efficiently removing oil from raffinate water during molybdenum ore hydrometallurgy, characterized in that: The steps include: Determination: Measure the redox potential Eh and oil content of the raffinate water; when the redox potential Eh of the raffinate water is ≤450mV, skip the adjustment step and directly enter the dosing reaction step; when the redox potential Eh of the raffinate water is >450mV, enter the adjustment step; Adjustment: Start stirring and add iron to the raffinate water through the iron dosing system until the redox potential of the raffinate water Eh ≤ 450mV; Dosing reaction: add H2O2 to the raffinate water through the H2O2 dosing system and stir the reaction at a constant temperature; Detection: Detect the oil content in the raffinate water after the dosing reaction. When the oil content is less than 10 mg / L, turn on the drainage pump, filter the raffinate water after the reaction through a bag filter, and then discharge it to the storage tank.

2. The method for efficiently removing oil from raffinate water in a molybdenum ore hydrometallurgy process according to claim 1, wherein: The redox potential Eh of the raffinate water is adjusted to be between 360mV and 440mV.

3. The method for efficiently removing oil from raffinate water in a molybdenum ore hydrometallurgy process according to claim 1, wherein: The iron agent includes iron powder, iron filings or ferrous sulfate.

4. The method for efficiently removing oil from raffinate water in a molybdenum ore hydrometallurgy process according to claim 1, wherein: H2O2 is an H2O2 solution with a mass percentage concentration of 20% to 40%.

5. The method for efficiently removing oil from raffinate water in a molybdenum ore hydrometallurgy process according to claim 4, wherein: The amount of H2O2 added is 7mL~12mLH2O2 for every 100mg of oil.

6. The method for efficiently removing oil from raffinate water in a molybdenum ore hydrometallurgy process according to claim 1, characterized in that: After adding H2O2, stir and react at a constant temperature of 60℃~80℃ for 5min~60min.

7. The method for efficiently removing oil from raffinate water in a molybdenum ore hydrometallurgy process according to any one of claims 1 to 6, characterized in that: The raffinate water comes from the raffinate water in the molybdenum ore hydrometallurgy process.

8. The method for efficiently removing oil from raffinate water in a molybdenum ore hydrometallurgy process according to claim 7, characterized in that: The raffinate water contains sulfuric acid, molybdenum, iron, oil and trace elements; the trace elements include one or more of uranium, silicon, calcium, phosphorus, sulfur and arsenic; the oil includes one or more of trioctyldecyl tertiary amine, di(2-ethylhexyl) phosphate, tributyl phosphate and kerosene.

9. The method for efficiently removing oil from raffinate water in a molybdenum ore hydrometallurgy process according to claim 8, characterized in that: The raffinate water has a sulfuric acid concentration of 5 g / L to 50 g / L, a ΣFe content of 1 g / L to 10 g / L, and an oil content of ≤200 mg / L.

10. A device for efficiently removing oil from raffinate water during molybdenum ore hydrometallurgy, characterized in that: The device is used for a method for efficiently removing oil from raffinate water in a molybdenum ore hydrometallurgy process as described in any one of claims 1 to 9, and the device includes a raffinate water feeding trough, a reactor, an iron agent dosing system, an H2O2 dosing system, a drainage system, a bag filter and a storage tank; the reactor main body is a constant temperature stirring tank, equipped with a liquid inlet, a liquid outlet, a sampling port, a constant temperature heating device, an online temperature monitoring system, an online redox potential monitoring system, a variable frequency adjustable speed mechanical stirring device, a liquid level meter and a dosing port.

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