Method and reaction device for synchronously and efficiently removing iron and organic matters

Abstract

The application discloses a method and a reaction device for synchronously and efficiently removing iron and organic matters, and belongs to the technical field of hydrometallurgy. The method comprises the following steps: taking a leaching solution of a zinc hydrometallurgy purification process, adjusting the pH by using a neutralizing agent a, maintaining the pH between 3.6-4.0, then conveying the solution to a leaching solution storage tank for preheating and stirring, after reaching a set temperature of 50-95 DEG C, injecting the solution into an iron removal reactor, adjusting the pH to be 4.0-5.0, introducing an oxidizing agent, controlling the flow rate to be 10-300 L / h, deeply removing the organic matters and iron ions in the solution, and after the reaction is finished, aging for 1-4 h, and then performing solid-liquid separation. The reaction device comprises a leaching solution storage tank, an iron removal reactor, an oxidizing agent supply system and the like. The application can efficiently and synchronously remove the iron ions and the organic matters in the solution, can greatly reduce the iron removal time, can reduce the catalyst and oxidizing agent consumption, has a good removal effect, and has a good application prospect.

Description

Technical Field

[0001] This invention belongs to the field of hydrometallurgical technology, and particularly relates to a method and reaction device for simultaneous and efficient iron precipitation and organic matter removal, which is applicable to solution purification treatment in zinc smelting process. Background Technology

[0002] In hydrometallurgical zinc refining, after the zinc concentrate is roasted and leached with hot acid or directly with oxygen pressure, zinc enters the leachate, while iron, which is associated with the ore, also dissolves into the solution. The presence of iron ions severely affects subsequent electrolysis processes, leading to reduced current efficiency and decreased cathode zinc quality. Therefore, it is essential to efficiently remove iron ions during the neutral leaching stage. Currently, the mainstream industrial iron removal methods include the jaundice process, the goethite process, and the hematite process. The jaundice process produces slag with low iron content and large volume, and because it adsorbs toxic elements such as arsenic, it is classified as hazardous solid waste, and long-term storage will put enormous pressure on the environment. Although the goethite process produces slag with slightly higher iron content, it is still classified as hazardous solid waste and is difficult to treat. While the hematite process can produce slag with relatively high iron content (classified as general solid waste), this method has extremely high equipment requirements, requiring operation under high temperature and pressure, resulting in extremely high technical barriers and energy consumption.

[0003] Furthermore, to improve the quality of electrolytic zinc and recover valuable metals, various organic substances (such as gums, β-naphthol, tannic acid, and various extractants) are often added during the production process. Excessive organic substances can lead to reduced current efficiency, increased energy consumption, and decreased product quality. Currently, methods for removing organic substances mainly include air flotation, activated carbon adsorption, ultrasonic demulsification and oil removal, membrane separation, and oxidation processes. However, these are usually carried out separately from the iron removal process, resulting in long process flows, complex operations, and high costs. Therefore, developing a technology that can simultaneously and deeply remove iron and organic substances, is simple, environmentally friendly, and cost-effective, has become an urgent problem to be solved in the hydrometallurgical zinc smelting industry. Summary of the Invention

[0004] Technical problem solved: In view of the technical problems existing in the prior art, the present invention provides a method and reaction device for simultaneous and efficient iron precipitation and organic matter removal, which has the advantages of simple process, high iron removal efficiency, low slag volume and environmental friendliness.

[0005] Technical solution: The present invention provides a method for simultaneous and efficient iron deposition and organic matter removal, comprising the following steps: Step 1: Take the leaching solution from the wet zinc smelting purification process. The initial pH value of the leaching solution is 2.0-3.6. Add neutralizing agent a to adjust the pH to 3.6-4.0. Transfer the adjusted solution to the leaching solution storage tank for preheating and stirring. After the solution temperature reaches 50-95℃, inject the solution into the iron removal reactor and adjust the pH of the solution to 4.0-5.0 in the iron removal reactor. Step 2: Introduce an oxidant into the iron removal reactor, control the oxidant flow rate to be 10-300 L / h, and react for 0.5-4 h to allow the organic matter in the solution to react with and be removed from the iron ions. Step 3: After the reaction is complete, the reaction slurry is aged for 1-4 hours, followed by solid-liquid separation to obtain a purified zinc solution and an iron-containing precipitate.

[0006] Preferably, the leaching solution contains zinc ions at a concentration of 1-100 g / L, total iron at a concentration of 1-5 g / L, and organic matter at a concentration of 1-5 g / L; the organic matter includes gum, soapberry powder, β-naphthol, tannic acid, and extractant P. 204 Extractant N 235 One or more of them.

[0007] Preferably, the neutralizing agent a is one of zinc metal oxide or carbonate; the oxidizing agent is one or more of compressed air, oxygen, and ozone.

[0008] The present invention also discloses a reaction apparatus for the above method, comprising: The leachate storage tank is equipped with a heating element, a feed pipe, a first mixing inlet, and a second mixing inlet; An iron removal reactor is connected to a leachate storage tank via a threaded interface. The reactor has an inner cylinder with a top plate at its top. A first mixing outlet and a second mixing outlet are located at the lower end of the inner cylinder. A neutralizing agent inlet is located on the side wall of the inner cylinder. An oxidant supply system, comprising a gas supply device, a gas pipeline, and a flow meter, is used to quantitatively supply oxidant to the iron removal reactor; A control unit is electrically connected to a pH electrode disposed within the iron removal reactor, and is used to monitor and adjust the pH value during the reaction process.

[0009] Preferably, the iron removal reactor is provided with a reactor cap on top and a corrosion-resistant lining on its inner wall; The iron removal reactor is provided with a tilting mechanism and a lifting device on both sides, and the tilting mechanism and the lifting device are connected to the iron removal reactor through a connecting mechanism.

[0010] Preferably, both the leachate storage tank and the iron removal reactor are equipped with an automatic stirring mechanism, and the stirring speed is adjustable.

[0011] Preferably, the gas supply device is an air compressor, an industrial oxygen tank, or an ozone generator; the gas enters the inner cylinder of the reactor through the first air inlet and the second air inlet; The industrial oxygen tank is equipped with a flow meter and a pressure valve; the ozone generator panel is equipped with a power supply, an oxygen source starter, and an ozone starter.

[0012] Preferably, the iron removal reactor is also equipped with an explosion-proof device and an exhaust port; the gas transmission pipe is made of corrosion-resistant material, and the flow meter has an accuracy of ±1%.

[0013] Preferably, the main body of the reaction device is made of polypropylene or stainless steel, with a temperature resistance range of -20 to 150°C; the corrosion-resistant lining is made of silicon carbide.

[0014] Preferably, a centrifugal pump is also connected to the feed pipe, the centrifugal pump being used to pump the leachate into the leachate storage tank.

[0015] Compared with the prior art, the present invention has at least the following beneficial effects: 1. This invention achieves simultaneous, deep, and efficient removal of iron and organic matter in a single process. Compared to traditional iron removal methods, the reaction time is shortened by 10-50%. The concentration of liquid iron after iron removal can be reduced to below 0.004 g / L, and the iron removal rate can reach over 99.6%, far superior to traditional iron removal methods. The residual TOC content in the solution is below 10 mg / L, and the removal effect of organic matter is significant. This invention combines two purification steps into one, simplifying the process, shortening the process flow, and reducing equipment investment and operating costs. The reaction conditions are mild (atmospheric pressure, 50-95℃), eliminating the need for expensive high-temperature and high-pressure equipment, resulting in low investment and operating costs and easy industrialization. 2. The iron slag produced by this invention has a high iron content, good filtration performance, and low slag volume. It can be used as a general solid waste for resource utilization (such as as a raw material for ironmaking) according to its properties. This avoids the environmental risks of generating hazardous waste slag by traditional iron removal methods, realizes high-value resource utilization of iron slag, reduces storage costs and environmental risks, and is in line with the concept of green metallurgy. 3. This process can effectively treat leachates containing various types of organic matter (gum, tannic acid, extractants, etc.) and has good versatility. 4. The reaction device has a high degree of automation, and the control system can achieve precise control of key parameters, ensuring stable operation and ease of use. Attached Figure Description

[0016] Figure 1 This is a process flow diagram of the method of the present invention; Figure 2 This is a curve showing the effect of different pH values ​​on iron removal rate and TOC removal rate when air is used as an oxidant in Example 1 of the present invention. Figure 3 The curves showing the effect of different amounts of tannic acid added on iron removal rate and TOC removal rate when air is used as an oxidant in Example 1 of this invention are shown. Figure 4This is a comparison chart showing the simultaneous removal effects of iron and tannic acid in Example 2 (oxygen as oxidant) and Example 3 (ozone as oxidant) of the present invention; Figure 5 This is a front view of the structure of the reaction apparatus of the present invention; Figure 6 for Figure 5 Main view of the structure of the leachate storage tank; Figure 7 for Figure 6 Partial top-view cross-section of the leachate storage tank; Figure 8 for Figure 5 Left cross-sectional view of the iron removal reactor; Figure 9 for Figure 5 Top view of the iron removal reactor; Figure 10 This is a schematic diagram of the industrial oxygen tank structure of the present invention; Figure 11 This is a top view of the ozone generator of the present invention.

[0017] Reference numerals: 1. Automatic stirring mechanism; 2. Leachate storage tank; 3. Heating element; 4. First mixing inlet; 5. Second mixing inlet; 6. First air inlet; 7. Explosion-proof device; 8. Air compressor; 9. Iron removal reactor; 10. Neutralizing agent inlet; 11. Reactor inner cylinder; 12. Second mixing outlet; 13. Support leg; 14. First mixing outlet; 15. Threaded interface; 16. Gas supply pipe; 17. Flow meter; 18. Feed pipe; 19. Second air inlet; 20. Connecting mechanism; 21. Corrosion-resistant lining; 22. Top plate; 23. Exhaust port; 24. Tilting mechanism and lifting device; 25. pH electrode; 26. Reactor cap; 27. Centrifugal pump; 28. Pressure valve; 29. ​​Industrial oxygen tank; 30. Ozone generator; 31. Power supply; 32. Oxygen source starter; 33. Ozone starter. Detailed Implementation

[0018] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the following will be described in conjunction with the accompanying drawings. Figures 1-11 The technical solutions of the embodiments of the present invention are clearly and completely described. Obviously, the described embodiments are only a part of the embodiments of the present invention, not all of them. All other embodiments obtained by those skilled in the art based on the described embodiments of the present invention are within the scope of protection of the present invention.

[0019] like Figure 1 As shown, this invention discloses a method for simultaneously and efficiently depositing iron and removing organic matter, comprising the following steps: (a) Leachate pretreatment: The leaching solution from the wet zinc smelting purification process contains zinc ions at a concentration of 1-100 g / L, total iron at a concentration of 1-5 g / L, and organic matter at a concentration of 1-5 g / L. The organic matter includes gum, soapberry powder, β-naphthol, tannic acid, and extractant P. 204 Extractant N 235 One or more of the following are used: the initial pH of the leachate is 2.0-3.6. First, neutralizing agent A is added to the leachate to adjust the pH to 3.6-4.0. Neutralizing agent A is one of zinc metal oxide or carbonate. Then, the adjusted solution is transferred to a leachate storage tank for preheating and continuous stirring. After the solution temperature reaches 50-95℃, the solution is injected into the iron removal reactor, where the pH is adjusted to the optimal reaction range of 4.0-5.0. The core purpose of pretreatment is to create optimal conditions for the reaction between organic matter and iron ions. Too high a pH will lead to zinc loss, while too low a pH will affect the reaction efficiency between organic matter and iron.

[0020] (II) Oxidation reaction: An oxidant (compressed air, oxygen, or ozone) is introduced into the iron removal reactor, and the flow rate of the oxidant is controlled at 10-300 L / h by a flow meter, and the reaction is carried out for 0.5-4 h. During this process, ferric ions (Fe³⁺) in the solution undergo complexation precipitation and catalytic oxidation reactions with organic matter, so as to achieve simultaneous deep removal of organic matter and iron ions.

[0021] (III) Post-processing: After the reaction, the reaction slurry is aged for 1-4 hours to promote flocculation and growth of the precipitate. Then, solid-liquid separation (such as filtration and sedimentation) is performed to obtain a purified zinc solution with extremely low iron content (e.g., below 0.004 g / L) and low total organic carbon (TOC) residue (e.g., below 10 mg / L), as well as a precipitate with high iron content that is easy to filter. The iron-containing precipitate can be washed and used as a raw material for ironmaking for resource utilization. Furthermore, alkali treatment (such as sodium hydroxide solution) can be used to dissolve the precipitate, reducing processing costs.

[0022] The working principle of this invention lies in: creatively utilizing Fe 3+ Dual interaction mechanisms with organic matter: ① Complexation precipitation mechanism: Fe in solution 3+ It rapidly undergoes coordination reactions with abundant active functional groups (such as hydroxyl -OH, carboxyl -COOH, etc.) in organic molecules to generate stable organic-iron composite precipitates with a three-dimensional network structure. These precipitates are large and dense flocs with excellent settling and filtration performance, far exceeding that of traditional ferric hydroxide colloids, thus achieving highly efficient precipitation and separation of iron while simultaneously encapsulating and immobilizing organic matter within the precipitate. ② Catalytic oxidation mechanism: Fe 3+It can act as a catalyst, activating functional groups in organic molecules and catalyzing the introduction of oxidants (such as O2 and O3) to generate stronger oxidizing species (such as hydroxyl radicals), which attack the organic molecular chains, causing them to break, open rings, or even mineralize into CO2 and H2O, thereby deeply degrading TOC in the solution. These two mechanisms promote each other, forming a synergistic "catalytic cycle" that achieves the simultaneous and efficient removal of iron and organic matter.

[0023] like Figures 5-11 As shown, the present invention also discloses a reaction apparatus for the above method, comprising the following main structural components: The leachate storage tank 2 is located at the top of the iron removal reactor 9 and is used to receive, store, preheat, and initially regulate the leachate. The leachate storage tank 2 is equipped with a heating element 3, a feed pipe 18, a first mixing inlet 4, and a second mixing inlet 5. A centrifugal pump 27 is also connected to the feed pipe 18, which pumps the leachate into the leachate storage tank 2. The leachate storage tank 2 is equipped with an automatic stirring mechanism 1 with adjustable stirring speed.

[0024] The iron removal reactor 9, serving as the core reaction vessel, is connected to the leachate storage tank 2 via a threaded interface 15. Support feet 13 are circumferentially distributed at the bottom of the iron removal reactor 9. An inner reactor cylinder 11 is installed inside the iron removal reactor 9, and an automatic stirring mechanism 1 with adjustable stirring speed is installed within the inner reactor cylinder 11. A top plate 22 is installed at the top of the iron removal reactor 9, and a first mixing outlet 14 and a second mixing outlet 12 are correspondingly located at the lower end of the inner reactor cylinder 11. A neutralizing agent inlet 10 is installed on the side wall of the inner reactor cylinder 11, and an oxidant distributor can also be installed within the inner reactor cylinder 11. A reactor cap 26 is installed at the top of the iron removal reactor 9 to facilitate heat preservation and prevent heat loss; a corrosion-resistant lining 21 made of silicon carbide is installed on its inner wall, suitable for acidic environments. The iron removal reactor 9 is also equipped with an explosion-proof device 7 and an exhaust port 23 to prevent localized high pressure and thermal expansion and contraction, ensuring operational safety.

[0025] Tilting mechanisms and lifting devices 24 are provided on both sides of the iron removal reactor 9. The tilting mechanisms and lifting devices 24 are connected to the iron removal reactor 9 through the connecting mechanism 20 to facilitate the tilting adjustment of the iron removal reactor 9 for slag discharge or maintenance.

[0026] An oxidant supply system is used to stably deliver and precisely control the oxidant flow rate to the iron removal reactor. The oxidant supply system includes a gas supply device, a gas pipeline 16, and a flow meter 17, for quantitatively supplying oxidant to the iron removal reactor 9. The gas supply device is an air compressor 8, an industrial oxygen tank 29, or an ozone generator 30. Gas enters the reactor inner cylinder 11 through a first inlet 6 and a second inlet 19. The industrial oxygen tank 29 is equipped with a flow meter 17 and a pressure valve 28. The ozone generator's panel is equipped with a power supply 31, an oxygen source starter 32, and an ozone starter 33. The gas pipeline 16 is made of corrosion-resistant material, and the flow meter 17 has an accuracy of ±1%.

[0027] The control unit is linked with the pH electrode 25 installed in the iron removal reactor 9, the temperature sensor installed in the leachate storage tank 2, and multiple flow meters used to measure the flow rate of gas or liquid, so as to realize the automatic monitoring and adjustment of key parameters such as reaction pH, temperature, and oxidant flow rate, and ensure the stability of process conditions.

[0028] Both the leachate storage tank 2 and the iron removal reactor 9 are equipped with an automatic stirring mechanism 1, with adjustable stirring speed to ensure uniform mixing of the solution; the main body of the reaction device is made of polypropylene or stainless steel, with a temperature range of -20-150℃.

[0029] The working principle or method of the reaction device of the present invention: The leachate is pumped into the leachate storage tank 2 through the feed pipe 18 by the centrifugal pump 27; the heating element 3 is activated and the automatic stirring mechanism 1 is started to uniformly preheat the solution to the set temperature. After preheating, the threaded interface is opened and the solution flows into the iron removal reactor 9 through the first mixing inlet 4 and the second mixing inlet 5; the pH electrode 25 monitors the pH in real time, and the control unit drives the feeding system to add neutralizing agent through the neutralizing agent inlet 10 to precisely adjust the pH to the set range. Subsequently, the oxidant (from the air compressor 8, industrial oxygen tank 29 or ozone generator 30) is controlled by the gas supply pipe 16 and the flow meter 17 and is introduced into the inner cylinder of the reactor from the first air inlet 6 and the second air inlet 19, and the reaction is continuously stirred; after the reaction, the slurry is discharged into the aging tank through the first mixing outlet 14 and the second mixing outlet 12, and is purified by solid-liquid separation.

[0030] The method and reaction apparatus provided by this invention have the following basic process flow: Figure 1 As shown, the core lies in creating optimal initial reaction conditions through specific pretreatment, and then using an oxidant at a suitable temperature and pH to initiate and maintain a synergistic precipitation-oxidation reaction between Fe³⁺ and organic matter. The invention will be further described in detail below with reference to specific embodiments.

[0031] Example 1: This example uses air as the oxidant, and the specific steps are as follows: (1) Take 1L of leaching solution from the wet zinc smelting purification process. Its composition is 1g / L zinc ion concentration, 1g / L total iron concentration, 1g / L tannic acid concentration, and the initial solution pH value is 3.55. Adjust the pH to 4.0±0.2 with zinc oxide. Pump the solution into the leaching solution storage tank for preheating. At the same time, turn on the agitator to fill the solution to about 60% of the volume from the bottom of the leaching solution storage tank. After the temperature reaches 70℃, inject it into the iron removal reactor 9 from the first mixing inlet 4 and the second mixing inlet 5. Further adjust the pH value to 4.5±0.2. (2) Compressed air is introduced as an oxidant, with a flow rate of 100 L / h, and the reaction is carried out for 1.5 h; (3) After the reaction is complete, the slurry is aged for 2.5 hours and then solid-liquid separation is carried out.

[0032] The test results showed that the iron removal rate was 99.85% and the residual TOC in the solution was 4 mg / L.

[0033] The reaction apparatus used in this embodiment is as follows: Figure 5-9 As shown, the leachate is transported to the leachate storage tank 2 by centrifugal pump 27, and after preheating, it is injected into the iron removal reactor 9 through the first mixing inlet 4 and the second mixing inlet 5; the oxidant is introduced by air compressor 8 through air pipe 16, and the flow rate is controlled by flow meter 17; the neutralization dosage is automatically adjusted according to the pH control system; after the reaction is completed, the slurry enters the aging tank from the first mixing outlet 14 and the second mixing outlet 12 for aging, and then solid-liquid separation is performed.

[0034] Example 2: This example uses oxygen as the oxidant, and the specific steps are as follows: (1) Take 1L of leaching solution from the wet zinc smelting purification process. Its composition is 10g / L zinc ion concentration, 1g / L total iron concentration, and 2g / L tannic acid concentration. The initial solution pH value is 3.5. Adjust the pH to 3.5±0.2 with zinc oxide. Pump the solution into the leaching solution storage tank for preheating. At the same time, turn on the agitator to fill the solution to about 60% of the volume from the bottom of the leaching solution storage tank. After the temperature reaches 80℃, inject it into the iron removal reactor 9 from the first mixing inlet 4 and the second mixing inlet 5. Further adjust the pH value to 4.0±0.2. (2) Introduce oxygen as an oxidant, control the flow rate at 20 L / h, and react for 1.5 h; (3) After the reaction is complete, the slurry is aged for 2.0 hours and then solid-liquid separation is carried out.

[0035] The test results showed that the iron removal rate was 99.8% and the residual TOC in the solution was 3 mg / L.

[0036] In the reaction apparatus used in this embodiment, the oxidant is introduced from the industrial oxygen tank 29 through the gas supply pipe 16, and the rest of the structure and operation mode are the same as in embodiment 1.

[0037] Example 3: This example uses ozone as an oxidant. The specific steps are as follows: (1) Take 1L of leaching solution from the wet zinc smelting purification process. Its composition is 10g / L zinc ion concentration, 1g / L total iron concentration, and 1g / L tannic acid concentration. The initial solution pH is 3.0. Adjust the pH to 3.5±0.2 with zinc oxide. Pump the solution into the leaching solution storage tank for preheating. At the same time, turn on the agitator to fill the solution to about 55% of the volume from the bottom of the leaching solution storage tank. After the temperature reaches 70℃, inject it into the iron removal reactor 9 from the first mixing inlet 4 and the second mixing inlet 5. Further adjust the pH to 4.0±0.2. (2) Ozone was introduced as an oxidant, with a flow rate of 10 L / h, and the reaction was carried out for 1.0 h; (3) After the reaction is complete, the slurry is aged for 1.0 h, and then solid-liquid separation is carried out.

[0038] The test results showed that the iron removal rate was 99.8% and the residual TOC in the solution was 1.6 mg / L.

[0039] In the reaction apparatus used in this embodiment, the oxidant is introduced from the ozone generator 30 through the gas supply pipe 16, and the rest of the structure and operation mode are the same as in embodiment 1.

[0040] Example 4: This example uses ozone as an oxidant to treat a high-zinc and high-iron solution. The specific steps are as follows: (1) Take 1L of leaching solution from the wet zinc smelting purification process. Its composition is 100g / L zinc ion concentration, 4g / L total iron concentration, and 2g / L tannic acid concentration. The initial solution pH value is 3.52. Adjust the pH to 3.5±0.2 with zinc oxide. Pump the solution into the leaching solution storage tank for preheating. At the same time, turn on the agitator to fill the solution to about 55% of the volume from the bottom of the leaching solution storage tank. After the temperature reaches 70℃, inject it into the iron removal reactor 9 from the first mixing inlet 4 and the second mixing inlet 5. Further adjust the pH value to 4.0±0.2. (2) Introduce ozone as an oxidant, control the flow rate at 10 L / h, and react for 40 min; (3) After the reaction is complete, the slurry is aged for 1.0 h, and then solid-liquid separation is carried out.

[0041] The test results showed that the iron removal rate was 99.88% and the residual TOC in the solution was 3.6 mg / L.

[0042] The reaction apparatus used in this embodiment is the same as that in Embodiment 3. The apparatus operates stably and is suitable for the purification of high zinc and high iron solutions.

[0043] Example 5: This example uses ozone as an oxidant to treat a solution containing various organic compounds. The specific steps are as follows: (1) Take 1L of leaching solution from the wet zinc smelting purification process. Its composition is 60g / L zinc ion concentration, 3g / L total iron concentration, and 0.2g / L gelatin concentration. The initial solution pH value is 3.2. Adjust the pH to 3.5±0.2 with zinc oxide. Pump the solution into the leaching solution storage tank for preheating. At the same time, turn on the agitator to fill the solution to about 50% of the volume from the bottom of the leaching solution storage tank. After the temperature reaches 70℃, inject it into the iron removal reactor 9 from the first mixing inlet 4 and the second mixing inlet 5. Further adjust the pH value to 4.0±0.2. (2) Ozone was introduced as an oxidant, with a flow rate of 10 L / h, and the reaction was carried out for 1.0 h; (3) After the reaction is complete, the slurry is aged for 1.5 hours and then solid-liquid separation is carried out.

[0044] The test results showed that the iron removal rate was 99.78% and the residual TOC in the solution was 7.0 mg / L.

[0045] The reaction apparatus used in this embodiment is the same as that in Embodiment 3. The apparatus operates stably and can efficiently remove various organic substances and iron ions from the solution.

[0046] Example 6: This example uses ozone as an oxidant to treat a solution containing β-naphthol. The specific steps are as follows: (1) Take 1L of leaching solution from the wet zinc smelting purification process. Its composition is 100g / L zinc ion concentration, 5g / L total iron concentration, 3g / L tannic acid concentration, and 0.1g / L β-naphthol concentration. The initial solution pH value is 2.7. Adjust the pH to 3.5±0.2 with zinc oxide. Pump the solution into the leaching solution storage tank for preheating. At the same time, turn on the agitator to fill the solution to about 55% of the volume from the bottom of the leaching solution storage tank. After the temperature reaches 70℃, inject it into the iron removal reactor 9 from the first mixing inlet 4 and the second mixing inlet 5. Further adjust the pH value to 4.0±0.2. (2) Ozone was introduced as an oxidant, with a flow rate of 15 L / h, and the reaction was carried out for 1.5 h; (3) After the reaction is complete, the slurry is aged for 1.0 h, and then solid-liquid separation is carried out.

[0047] The test results showed that the iron removal rate was 99.62% and the residual TOC in the solution was 10 mg / L.

[0048] The reaction apparatus used in this embodiment is the same as that in Example 3. The apparatus operates stably and can effectively remove β-naphthol, tannic acid and iron ions from the solution.

[0049] Example 7: This example uses ozone as an oxidant to treat a high-concentration solution containing various organic compounds. The specific steps are as follows: (1) Take 1L of leaching solution from the wet zinc smelting purification process. Its composition is 100g / L zinc ion concentration, 5g / L total iron concentration, 2g / L tannic acid concentration, 0.1g / L β-naphthol concentration, and 0.1g / L gelatin concentration. The initial solution pH value is 2.3. Adjust the pH to 3.5±0.2 with zinc oxide. Pump the solution into the leaching solution storage tank for preheating. At the same time, turn on the agitator to fill the solution to about 55% of the volume from the bottom of the leaching solution storage tank. After the temperature reaches 75℃, inject it into the iron removal reactor 9 from the first mixing inlet 4 and the second mixing inlet 5. Further adjust the pH value to 4.5±0.2. (2) Compressed air is introduced as an oxidant, with a flow rate of 50 L / h, and the reaction is carried out for 2.0 h; (3) After the reaction is complete, the slurry is aged for 2.0 hours and then solid-liquid separation is carried out.

[0050] The test results showed that the iron removal rate was 99.60% and the residual TOC in the solution was 10 mg / L.

[0051] The reaction apparatus used in this embodiment is the same as that in Embodiment 3, and can efficiently process high-concentration zinc smelting leachate containing a variety of organic substances.

[0052] The above are preferred embodiments of the present invention. It should be noted that, for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A method for simultaneously and efficiently depositing iron and removing organic matter, characterized in that, Includes the following steps: Step 1: Take the leaching solution from the wet zinc smelting purification process. The initial pH value of the leaching solution is 2.0-3.

6. Add neutralizing agent a to adjust the pH to 3.6-4.

0. Transfer the adjusted solution to the leaching solution storage tank for preheating and stirring. After the solution temperature reaches 50-95℃, inject the solution into the iron removal reactor and adjust the pH of the solution to 4.0-5.0 in the iron removal reactor. Step 2: Introduce an oxidant into the iron removal reactor, control the oxidant flow rate to be 10-300 L / h, and react for 0.5-4 h to allow the organic matter in the solution to react with and be removed from the iron ions. Step 3: After the reaction is complete, the reaction slurry is aged for 1-4 hours, followed by solid-liquid separation to obtain a purified zinc solution and an iron-containing precipitate.

2. The method for simultaneous and efficient iron deposition and organic matter removal according to claim 1, characterized in that, In step 1, the leaching solution contains zinc ions at a concentration of 1-100 g / L, total iron at a concentration of 1-5 g / L, and organic matter at a concentration of 1-5 g / L; the organic matter includes gum, soapberry powder, β-naphthol, tannic acid, and extractant P. 204 Extractant N 235 One or more of them.

3. The method for simultaneous and efficient iron deposition and organic matter removal according to claim 1, characterized in that, The neutralizing agent a is one of zinc metal oxide or carbonate; the oxidizing agent is one or more of compressed air, oxygen, and ozone.

4. A reaction apparatus for use in the method of any one of claims 1-3, characterized in that, include: The leachate storage tank (2) is equipped with a heating element (3), a feed pipe (18), a first mixing inlet (4), and a second mixing inlet (5); The iron removal reactor (9) is connected to the leachate storage tank (2) through a threaded interface (15); the iron removal reactor (9) is provided with a reactor inner cylinder (11) and a top plate (22) at its top; the lower end of the reactor inner cylinder (11) is provided with a first mixing outlet (14) and a second mixing outlet (12); the side wall of the reactor inner cylinder (11) is provided with a neutralizing agent inlet (10); An oxidant supply system, comprising a gas supply device, a gas pipeline (16) and a flow meter (17), is used to quantitatively supply oxidant to the iron removal reactor (9); The control unit is electrically connected to a pH electrode (25) correspondingly disposed in the iron removal reactor (9) for monitoring and adjusting the pH value during the reaction process.

5. The reaction apparatus according to claim 4, characterized in that, The iron removal reactor (9) is provided with a reactor cap (26) on top and a corrosion-resistant lining (21) on its inner wall. The iron removal reactor (9) is provided with a tilting mechanism and a lifting device (24) on both sides. The tilting mechanism and the lifting device (24) are connected to the iron removal reactor (9) through a connecting mechanism (20).

6. The reaction apparatus according to claim 4, characterized in that, Both the leachate storage tank (2) and the iron removal reactor (9) are equipped with an automatic stirring mechanism (1), and the stirring speed is adjustable.

7. The reaction apparatus according to claim 4, characterized in that, The gas supply device is an air compressor (8), an industrial oxygen tank (29), or an ozone generator (30); the gas enters the reactor inner cylinder (11) through the first air inlet (6) and the second air inlet (19); The industrial oxygen tank (29) is equipped with a flow meter (17) and a pressure valve (28); the panel of the ozone generator is equipped with a power supply (31), an oxygen source starter (32) and an ozone starter (33).

8. The reaction apparatus according to claim 4, characterized in that, The iron removal reactor (9) is also equipped with an explosion-proof device (7) and an exhaust port (23); the gas transmission pipe (16) is made of corrosion-resistant material, and the flow meter (17) has an accuracy of ±1%.

9. The reaction apparatus according to claim 4, characterized in that, The main body of the reaction device is made of polypropylene or stainless steel, with a temperature range of -20 to 150°C; the corrosion-resistant lining (21) is made of silicon carbide.

10. The reaction apparatus according to claim 6, characterized in that, A centrifugal pump (27) is also connected to the feed pipe (18), which is used to pump the leachate into the leachate storage tank (2).

Images