Zinc hydrometallurgy short-process purification and impurity removal method

Abstract

The invention relates to a zinc hydrometallurgy short-process purification and impurity removal method which comprises the following steps: (1) mixing a purification and impurity removal reagent and a waste electrolyte in a preparation reactor to prepare mixed slurry with the concentration of 0.1-50g / L; (2) lifting the leached middle supernatant solution in the zinc hydrometallurgy process into a high-efficiency heat exchanger by adopting a lifting pump for heating, and keeping the temperature of the middle supernatant in a heater at 50-80 DEG C; and (3) inputting the mixed slurry obtained in the step (1) into a high-efficiency reactor through a reagent pump, inputting the hot medium-supernatant obtained in the step (2) into the high-efficiency reactor through a booster pump, carrying out equivalence purification reaction on the mixed slurry and the hot medium-supernatant, and filtering to respectively obtain purified liquid and purified residues. According to the method, the impurities in the zinc hydrometallurgy system can be efficiently removed, the production efficiency is improved, the zinc loss in the smelting process is reduced, then resource recycling of valuable metal cobalt and nickel is achieved, meanwhile, pollution to the environment is relieved to a certain degree, and the production cost is reduced.

Description

Technical Field

[0001] The invention relates to the field of purification of hydrometallurgical zinc smelting, and in particular to a short-process purification and impurity removal method for hydrometallurgical zinc smelting. Background Art

[0002] At present, hydrometallurgical zinc smelting plants generally adopt the traditional three-stage zinc powder replacement + antimony salt purification process. With the rapid development of the hydrometallurgical zinc industry, the raw materials of the hydrometallurgical zinc system have become diversified, the raw material composition has become more complex, and the content of harmful impurities has gradually increased. In order to improve the purification effect, the amount of zinc powder added to the solution has to be increased, resulting in increased zinc powder consumption and gradually increased costs. In addition, the copper-cadmium slag and nickel-cobalt slag produced contain a large amount of zinc powder, which brings huge pressure to the production system and causes great waste of resources. Summary of the invention

[0003] The technical problem to be solved by the present invention is to provide a short-process purification and impurity removal method for hydrometallurgical zinc smelting which can reduce production cost and improve production efficiency.

[0004] In order to solve the above problems, a short-process purification and impurity removal method for hydrometallurgical zinc smelting according to the present invention comprises the following steps: (1) Mix the purification and impurity removal reagent with the waste electrolyte in a preparation reactor to prepare a mixed slurry with a concentration of 0.1~50g / L; (2) The supernatant solution in the leaching process of hydrometallurgical zinc smelting is lifted to a high-efficiency heat exchanger for heating by a lifting pump, and the temperature of the supernatant in the heater is maintained at 50℃~80℃; ⑶ The mixed slurry obtained in step ⑴ is input into the high-efficiency reactor through a reagent pump, and the hot supernatant obtained in step ⑵ is input into the high-efficiency reactor through a booster pump. The two are subjected to purification reaction in equal amounts, and purified liquid and purified residue are obtained by filtration.

[0005] The purification and impurity removal reagent in step (1) refers to one or a mixture of zinc powder and sodium thiamethoxam.

[0006] The waste electrolyte in step (1) refers to the waste electrolyte produced by the hydrometallurgical zinc electrolysis process.

[0007] In step (3), the high-efficiency reactor includes a shell; a high-efficiency agitator is arranged in the shell, and the rotating shaft of the high-efficiency agitator extends out of the top of the shell and is connected to the stirring motor; a discharge pipe with a discharge port is arranged on one side of the shell, and a sampling port and a liquid inlet pipe with a liquid inlet are respectively arranged on the bottom; a feeding pipe with a reagent inlet is connected to the liquid inlet; the liquid inlet is connected to the liquid outlet I of the booster pump; the reagent inlet is connected to the liquid outlet II of the reagent pump; the discharge port is provided with a concentration probe integrating four elements of Cu, Cd, Co and Ni, and the concentration probe is connected to a concentration signal conversion computer and is interlocked with the reagent pump frequency regulator.

[0008] The sampling port and the reagent inlet are both provided with control valves.

[0009] The sampling port and the reagent liquid inlet are respectively arranged on both sides of the liquid inlet.

[0010] Compared with the prior art, the present invention has the following advantages: 1. The present invention conducts efficient mixing reaction on the mixed slurry of the purification and impurity removal reagent and the waste electrolyte and the supernatant in a high-efficiency reactor, realizes the equivalent efficient reaction of impurities and the purification reagent in a very short time, and forms fine-particle purification slag which gradually forms condensed large-particle purification slag under stirring, thereby realizing the efficient removal of impurities such as copper, cadmium, cobalt, nickel and the like in the supernatant of hydrometallurgical zinc smelting.

[0011] 2. The method of the present invention can realize the efficient removal of impurities in the hydrometallurgical zinc smelting system, improve production efficiency, reduce zinc loss in the smelting process, and then realize the resource recovery of valuable metals cobalt and nickel. At the same time, it reduces the pollution to the environment to a certain extent, which is of great significance to improving the adaptability of the hydrometallurgical zinc smelting system, reducing production costs, and improving the economic benefits and resource utilization of enterprises. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] The specific implementation modes of the present invention are further described in detail below in conjunction with the accompanying drawings.

[0013] Figure 1 It is a process flow chart of the present invention.

[0014] Figure 2 It is a schematic diagram of a high-efficiency reactor in the present invention.

[0015] In the figure: 1- stirring motor; 2- shell; 3- high-efficiency stirrer; 4- discharge port; 5- sampling port; 6- liquid inlet; 7- reagent inlet; 8- concentration probe. DETAILED DESCRIPTION

[0016] like Figure 1 As shown, a short-process purification and impurity removal method for hydrometallurgical zinc smelting comprises the following steps: (1) Mix the purification and impurity removal reagent with the waste electrolyte in a preparation reactor to prepare a mixed slurry with a concentration of 0.1~50g / L.

[0017] Wherein: the purification and impurity removal agent refers to one or a mixture of zinc powder and sodium fumer. The specific use is adjusted according to the purification effect of hydrometallurgical zinc smelting.

[0018] Waste electrolyte refers to the waste electrolyte produced by the hydrometallurgical zinc electrolysis process.

[0019] (2) The supernatant solution in the leaching process of wet zinc smelting is lifted to a high-efficiency heat exchanger for heating by a lifting pump, and the temperature of the supernatant in the heater is maintained at 50℃~80℃.

[0020] ⑶ The mixed slurry obtained in step ⑴ is input into the high-efficiency reactor through a reagent pump, and the hot supernatant obtained in step ⑵ is input into the high-efficiency reactor through a booster pump. The high-efficiency reactor is turned on, and the two are subjected to a purification reaction in equal amounts to form a mixed slurry of purified slag and purified liquid. The mixed slurry is discharged from the high-efficiency reactor through a discharge port 4, and the mixed slurry is sent to a filtration process for filtration by a filter pump to obtain purified liquid and purified slag, respectively. The purified liquid is sent to the electrolysis section for zinc electrowinning production, and the purified slag is sent to the comprehensive recovery section for comprehensive recovery of copper, cadmium, cobalt, and nickel.

[0021] like Figure 2 As shown, the high-efficiency reactor includes a shell 2; a high-efficiency stirrer 3 is arranged in the shell 2, and the rotating shaft of the high-efficiency stirrer 3 extends out of the top of the shell 2 and is connected to the stirring motor 1; a discharge pipe with a discharge port 4 is arranged on one side of the shell 2, and a sampling port 5 and a liquid inlet pipe with a liquid inlet 6 are respectively arranged on the bottom; a feeding pipe with a reagent inlet 7 is connected to the liquid inlet pipe; the liquid inlet 6 is connected to the liquid outlet Ⅰ of the booster pump; the reagent inlet 7 is connected to the liquid outlet Ⅱ of the reagent pump; the discharge port 4 is provided with a concentration probe 8 integrating four elements of Cu, Cd, Co, and Ni, and the concentration probe 8 is connected to a concentration signal conversion computer and is interlocked with a reagent pump frequency modulator. The frequency modulator is used to adjust the reagent pump speed according to the impurity ion concentration in the solution, thereby controlling the reagent dosage and the impurity ion amount in the supernatant to always be equivalent.

[0022] The sampling port 5 and the reagent inlet 7 are both provided with control valves. The sampling port 5 and the reagent inlet 7 are respectively provided on both sides of the inlet 6.

[0023] The high-efficiency agitator 3 is different from the ordinary paddle-type agitator. It includes a two-layer wedge-shaped high-speed agitator, which can achieve full mixing of solid and liquid and crush and reshape the formed particles. It prevents zinc powder or sodium fumer from forming precipitation and wrapping the purification reagent during the wet zinc smelting purification process, thereby improving the reagent utilization rate and reaction efficiency. It can use the CMA agitator produced by Guomao Group.

[0024] Example 1 The chemical composition of the supernatant extract is shown in Table 1 below.

[0025] Table 1 Chemical composition of the supernatant Implementation steps: ⑴ 1 kg of purification and impurity removal reagent is reacted with 10 m³ of waste electrolyte in a preparation reactor to form a mixed slurry.

[0026] (2) The supernatant solution in the leaching process of wet zinc smelting is lifted to a high-efficiency heat exchanger for heating by a lifting pump, and the temperature of the supernatant in the heater is maintained at 50℃~80℃.

[0027] ⑶ The mixed slurry obtained in step ⑴ is input into the high-efficiency reactor through a reagent pump, and the hot supernatant obtained in step ⑵ is input into the high-efficiency reactor through a booster pump. The high-efficiency reactor is turned on, and the two are subjected to a purification reaction in equal amounts to form a mixed slurry of purified slag and purified liquid. The mixed slurry is discharged from the high-efficiency reactor through a discharge port 4, and the mixed slurry is sent to a filtration process for filtration by a filter pump to obtain purified liquid and purified slag, respectively. The purified liquid is sent to the electrolysis section for zinc electrowinning production, and the purified slag is sent to the comprehensive recovery section for comprehensive recovery of copper, cadmium, cobalt, and nickel.

[0028] The chemical composition of the supernatant after purification is shown in Table 2.

[0029] Table 2 Chemical composition of purification solution The contents of Cu, Cd, Co and Ni in the purified slag were determined after drying, see Table 3.

[0030] Table 3 Purification slag composition Example 2 The chemical composition of the supernatant is shown in Table 4.

[0031] Table 4 Chemical composition of the supernatant Implementation steps (1) 25 kg of purification and impurity removal reagent is reacted with 10 m³ of waste electrolyte in a preparation reactor to form a mixed slurry; (2) ~ (3) Same as Example 1.

[0032] After purification, the composition of the purified liquid is shown in Table 5.

[0033] Table 5 Chemical composition of purification solution The contents of Cu, Cd, Co and Ni in the purified slag were determined after drying, see Table 6.

[0034] Table 6 Purification slag composition Example 3 The chemical composition of the supernatant is shown in Table 7.

[0035] Table 7 Chemical composition of the supernatant Implementation steps: (1) 500 kg of purification and impurity removal reagent is reacted with 10 m³ of waste electrolyte in a preparation reactor to form a mixed slurry; (2) ~ (3) Same as Example 1.

[0036] After purification, the composition of the purified liquid is shown in Table 8.

[0037] Table 8 Chemical composition of purification solution The contents of Cu, Cd, Co and Ni in the purified slag were determined after drying, see Table 9.

[0038] Table 9 Purification slag composition In summary, the method of the present invention can achieve efficient purification of the supernatant in the hydrometallurgical zinc smelting system.

Claims

1. A short-process purification and impurity removal method for hydrometallurgical zinc smelting, comprising the following steps: (1) Mix the purification and impurity removal reagent with the waste electrolyte in a preparation reactor to prepare a mixed slurry with a concentration of 0.1~50g / L; (2) The supernatant solution in the leaching process of hydrometallurgical zinc smelting is lifted to a high-efficiency heat exchanger for heating by a lifting pump, and the temperature of the supernatant in the heater is maintained at 50℃~80℃; ⑶ The mixed slurry obtained in step ⑴ is input into the high-efficiency reactor through a reagent pump, and the hot supernatant obtained in step ⑵ is input into the high-efficiency reactor through a booster pump. The two are subjected to purification reaction in equal amounts, and purified liquid and purified residue are obtained by filtration.

2. A short-process purification and impurity removal method for hydrometallurgical zinc smelting as claimed in claim 1, characterized in that: The purification and impurity removal reagent in step (1) refers to one or a mixture of zinc powder and sodium thiamethoxam.

3. A short-process purification and impurity removal method for hydrometallurgical zinc smelting as claimed in claim 1, characterized in that: The waste electrolyte in step (1) refers to the waste electrolyte produced by the hydrometallurgical zinc electrolysis process.

4. A short-process purification and impurity removal method for hydrometallurgical zinc smelting as claimed in claim 1, characterized in that: In step (3), the high-efficiency reactor comprises a shell (2); a high-efficiency stirrer (3) is arranged in the shell (2), and the rotating shaft of the high-efficiency stirrer (3) extends out of the top of the shell (2) and is connected to the stirring motor (1); a discharge pipe with a discharge port (4) is arranged on one side of the shell (2), and a sampling port (5) and a liquid inlet pipe with a liquid inlet (6) are arranged on the bottom; a feeding pipe with a reagent liquid inlet (7) is connected to the liquid inlet pipe; the liquid inlet (6) is connected to the liquid outlet I of the booster pump; the reagent liquid inlet (7) is connected to the liquid outlet II of the reagent pump; the discharge port (4) is provided with a concentration probe (8) integrating four elements of Cu, Cd, Co and Ni, and the concentration probe (8) is connected to a concentration signal conversion computer and is interlocked with the reagent pump frequency modulator.

5. A short-process purification and impurity removal method for hydrometallurgical zinc smelting as claimed in claim 4, characterized in that: The sampling port (5) and the reagent inlet (7) are both provided with control valves.

6. A short-process purification and impurity removal method for hydrometallurgical zinc smelting as claimed in claim 4, characterized in that: The sampling port (5) and the reagent liquid inlet (7) are respectively arranged on both sides of the liquid inlet (6).

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