CN-116732337-B - Method for combined leaching of high-silicon zinc roasted ore and high-sulfur zinc oxide powder

Abstract

The invention relates to a method for combined leaching of high-silicon zinc roasted ore and high-sulfur zinc oxide powder, belonging to the technical field of hydrometallurgy. The method comprises the steps of neutral leaching high-sulfur zinc oxide powder to obtain zinc oxide powder leaching slag and zinc powder leaching liquid, mixing the zinc powder leaching liquid with high-silicon zinc calcine to obtain zinc ore leaching slag and zinc ore leaching liquid, mixing the zinc powder leaching slag with the zinc ore leaching slag, carrying out low-acid leaching to obtain low-leaching slag and low-leaching liquid, carrying out hot acid leaching on the low-leaching slag to obtain hot-dipping slag and hot-dipping liquid, carrying out high-acid leaching on the hot-acid slag to obtain lead silver slag products and high-leaching liquid, neutralizing and reducing the hot-dipping liquid by high-sulfur zinc oxide powder to obtain neutralization liquid and neutralization slag, and mineralizing and precipitating iron by the neutralization liquid to obtain hematite products and iron-removing liquid. The invention can effectively control the leaching of silicon in the leaching process of the high-silicon zinc calcine, synchronously realize the oxidation leaching of sulfide in zinc oxide powder and the reduction leaching of zinc ferrite in zinc calcine, and simplify the leaching process of zinc roasted ores and zinc oxide powder.

Inventors

• DENG ZHIGAN
• CHEN PEIYIN
• YAN CHUANMING
• WU JUN
• LI MINTING
• ZHAO XI
• Zhao Xiongyu
• ZENG PENG
• WEI CHANG
• YANG RONGJING
• LIU JIANPING
• LI XINGBIN
• MA YUNSHAN

Assignees

• 昆明理工大学
• 云南金鼎锌业有限公司

Dates

Publication Date

20260505

Application Date

20230615

Claims (8)

1. 1. A method for leaching high-silicon zinc roasted ore and high-sulfur zinc oxide powder in a combined way is characterized by comprising the following specific steps: (1) Adding high-sulfur zinc oxide powder into waste electrolyte to perform neutral leaching to obtain zinc oxide powder intermediate leaching slag and zinc powder intermediate leaching liquid, wherein the solid-to-liquid ratio g of the high-sulfur zinc oxide powder to the waste electrolyte is 1:4-4.2, the neutral leaching temperature is 70-80 ℃, the time is 1.5-2 h, and the end point pH value is 4.8-5.1; (2) Mixing zinc powder immersion liquid and high-silicon zinc calcine to obtain slurry, introducing ferrous ions in air to oxidize the slurry, adding simulated low immersion liquid prepared by wet zinc-smelting waste electrolyte and zinc sulfate solution, slowly adding the wet zinc-smelting waste electrolyte to control the pH of the slurry to be 1.5-2.0 and react for 1-1.5 hours at the temperature of 70-80 ℃ and the initial pH of 2.5-3.0, slowly adding high-silicon zinc calcine to control the pH of the slurry to be 5.0-5.2 and react for 1-1.5 hours to obtain zinc ore immersion slag and zinc ore immersion liquid, and conveying the zinc ore immersion liquid to a wet zinc-smelting purification process, wherein the simulated low immersion liquid contains 119-122 g/L zinc and 0.51-0.55 g/L iron and has the pH value of 2.57-2.96; (3) Mixing the zinc powder leaching slag with the zinc ore leaching slag, adding a simulated iron-removing solution prepared from a wet zinc smelting waste electrolyte and a zinc sulfate solution, and performing low-acid leaching to obtain low leaching slag and low leaching liquid, wherein the low leaching liquid returns to the step (2) to replace the simulated low leaching liquid, and the simulated iron-removing solution contains 26-29 g/L of sulfuric acid, 112-116 g/L of zinc and 2.37-2.95 g/L of iron; (4) Adding the low leaching slag into a simulated high leaching solution prepared from wet zinc smelting waste electrolyte and zinc sulfate solution, and performing hot acid leaching to obtain hot leaching slag and hot leaching solution, wherein the hot leaching is used for synchronously realizing oxidation leaching of sulfide and reduction leaching of zinc ferrite, and the simulated high leaching solution contains 102-118 g/L of sulfuric acid, 52-61 g/L of zinc and 7.51-7.82 g/L of iron; (5) Adding hot acid residues into wet zinc smelting waste electrolyte to perform high acid leaching to obtain high leaching liquid and lead silver residues, and returning the high leaching liquid to the step (4) to replace the simulated high leaching liquid; (6) Neutralizing and reducing the hot leaching solution by high-sulfur zinc oxide powder to obtain a neutralization solution and neutralization residues, and returning the neutralization residues to the step (4) to be combined with the low leaching residues for hot acid leaching; (7) And (3) carrying out low-temperature hematite iron removal on the neutralization solution at the temperature of 150-160 ℃ and the oxygen partial pressure of 0.3-0.5 MPa for 3-4 hours to obtain hematite products and iron-removed liquid, and returning the iron-removed liquid to the step (3) to replace the simulated iron-removed liquid.
2. 2. The method for leaching high-silicon zinc roasted ore and high-sulfur zinc oxide powder in combination according to claim 1, wherein the sulfur content in the high-sulfur zinc oxide powder in the step (1) is more than 5 weight percent.
3. 3. The method for leaching the high-silicon zinc roasted ore and the high-sulfur zinc oxide powder in a combined manner is characterized in that when the leaching solution in the zinc powder in the step (2) is mixed with the high-silicon zinc roasted ore, the mass ratio of the high-silicon zinc roasted ore to the high-sulfur zinc oxide powder in the step (1) is 1:0.75-0.80.
4. 4. The method for combined leaching of high-silicon zinc roasted ores and high-sulfur zinc oxide powder, which is characterized in that the low-acid leaching temperature in the step (3) is 80-90 ℃, the time is 1.5-2 h, and the pH of a leaching system is 2.5-3.5.
5. 5. The method for leaching the high-silicon zinc roasted ore and the high-sulfur zinc oxide powder in a combined way, which is characterized in that the temperature of the hot acid leaching in the step (4) is 80-90 ℃, the time is 2.0-2.5 h, and the end point pH is 0.3-0.5.
6. 6. The method for combined leaching of high-silicon zinc roasted ores and high-sulfur zinc oxide powder, which is characterized in that the high-acid leaching temperature in the step (5) is 80-90 ℃, the time is 2.5-3.0 h, and the concentration of end-point sulfuric acid is 100-120 g/L.
7. 7. The method for combined leaching of high-silicon zinc roasted ores and high-sulfur zinc oxide powder, which is characterized in that the adding amount of the high-sulfur zinc oxide powder in the step (6) is 23-27% of the mass of the high-sulfur zinc oxide powder in the step (1), the neutralization and reduction temperature is 80-90 ℃, the pH of a solution is 4.0-5.0, and Fe 3+ in the neutralization solution is less than 0.2 g/L.
8. 8. The method for combined leaching of high-silicon zinc roasted ores and high-sulfur zinc oxide powder according to claim 1, wherein the concentration of iron in the solution after iron removal in the step (7) is less than 3g/L.

Description

Method for combined leaching of high-silicon zinc roasted ore and high-sulfur zinc oxide powder Technical Field The invention relates to a method for combined leaching of high-silicon zinc roasted ore and high-sulfur zinc oxide powder, belonging to the technical field of hydrometallurgy. Background Zinc smelting is mainly performed by a wet method, and the yield of the zinc smelting is more than 85% of the world zinc yield. The conventional zinc hydrometallurgy process flow comprises roasting-leaching (neutral leaching+weak acid leaching) -purifying-electro-deposition, and zinc leaching slag produced after weak acid leaching is mainly composed of zinc ferrite. The zinc leaching residue treatment method comprises a fire process and a wet process, wherein the fire process is mainly a rotary kiln volatilization method and a fuming furnace play method, has strong adaptability to raw materials, but has high energy consumption, heavy environmental burden and relatively low recovery rate of valuable metals. The hot acid and high acid leaching can effectively destroy zinc ferrite in zinc leaching slag to realize high-efficiency leaching of zinc, but when the leaching rate of zinc is improved to 95%, the leaching rate of iron is also up to more than 95%, most of iron exists in a Fe 3+ form, zinc-iron separation is needed to be carried out on the solution, and the iron removal method is divided into jarosite method, goethite method and hematite method according to the precipitation form of iron in the solution. When iron is removed by adopting a goethite method or a hematite method, fe 3+ in the solution is reduced to Fe 2+. The types of reducing agents currently applicable to industrial production are sulfur dioxide and zinc sulfide concentrate. The leaching of sulfur dioxide has the advantages of high reduction efficiency and thorough reduction, but sulfate radical is introduced in the reduction process, so that lime is needed to be used for neutralization to produce gypsum slag for balancing sulfate radical ions introduced by reduction of sulfur dioxide in order to realize acid balance. The zinc sulfide concentrate serving as the reducing agent has the advantages of small investment, low running cost and the like, but the reduction efficiency is low when the zinc sulfide concentrate is reduced at normal pressure, and the reduction leaching slag is unreacted zinc concentrate and elemental sulfur and needs to be subjected to secondary treatment. In addition, the zinc calcine obtained by the fluidized bed roasting of the high-silicon zinc sulfide concentrate contains a large amount of zinc ferrite, and also contains silicon with higher content, and the leaching of the high-silicon zinc calcine needs to take effective control measures so that the silicon enters the leaching liquid as little as possible to ensure the sedimentation and filtration of ore pulp and the subsequent purification effect. The zinc-containing lead-sulfur zinc oxide powder is obtained by adopting a technical route of photoelectric waste disposal-pyrogenic volatilization enrichment in the prior art, and because the low-grade lead-zinc oxide ore has higher silicon and sulfur content, the mineral characteristics of the zinc oxide powder produced by the method are completely different from those of the zinc oxide powder volatilized by a wet zinc leaching slag pyrogenic process, especially the sulfur content reaches 5-7%, and the contents of silver, indium, germanium and the like are extremely low. Aiming at how to solve the leaching of sulfides by high-sulfur zinc oxide powder so as to realize the efficient leaching of the zinc oxide powder, the recycling of leaching slag and other problems, the method is needed to be solved. Disclosure of Invention Aiming at the problems of low leaching rate of high-sulfur zinc oxide powder, control of silicon in the leaching process of high-silicon zinc calcine, reduction leaching of zinc ferrite and the like, the invention provides a method for jointly leaching high-silicon zinc roasted ore and high-sulfur zinc oxide powder, which is used for effectively controlling the leaching of silicon in the leaching process of high-silicon zinc oxide calcine, synchronously realizing the oxidation leaching of sulfide in zinc oxide powder and the reduction leaching of zinc ferrite in zinc calcine, simplifying the leaching process of zinc roasted ore and zinc oxide powder, improving the zinc leaching rate and improving the quality of lead silver slag. A method for leaching high-silicon zinc roasted ore and high-sulfur zinc oxide powder in a combined way comprises the following specific steps: (1) Adding high-sulfur zinc oxide powder into the waste electrolyte for neutral leaching to obtain zinc oxide powder leaching residues and zinc powder leaching liquid; (2) Mixing the zinc powder immersion liquid with high-silicon zinc calcine to obtain slurry, introducing ferrous ions in the air oxidation slurry, adding simulated low immer