Zinc cyanide barren solution treatment method

Abstract

The invention relates to a method for treating zinc-containing cyanide barren solution, comprising the following process steps and conditions: sulfuration acidification reaction, first adding soluble sulfide to the zinc-containing cyanide barren solution, then adding concentrated sulfuric acid to carry out acidification reaction, and adjusting the pH value of the solution , add PAM, set aside for settling, solid-liquid separation Ⅰ, separate sediment Ⅰ, tail gas and supernatant, and transport sediment Ⅰ to the zinc smelting enterprise for comprehensive recycling; to neutralize the sediment, first add Alkali, adjust the pH value to 9.0-11.5 for neutralization and precipitation, then solid-liquid separation II, separate sediment II and tail water, sediment II and cyanide tailings are treated together, tail water is returned to the cyanide system for reuse, and tail gas recovery , send the tail gas produced in the first step to the absorption tower through negative pressure, add lye, separate the absorption liquid and empty the purified gas, and return the absorption liquid to neutralize the precipitation. It has the ability to efficiently remove Zn, Cu, Fe and other metals, efficient recovery of cyanide, toxic and harmful gas absorption treatment, comprehensive recovery of Zn and Cu in sediment, short process flow, simple and safe operation, easy to implement, etc., suitable for zinc-containing cyanide barren solution in gold smelting industry Handle the application.

Description

technical field [0001] The invention relates to a hydrometallurgical method, in particular to a method for treating zinc-containing cyanide barren liquid, which is suitable for the treatment and application of zinc-containing cyanide barren liquid in the gold smelting industry. Background technique [0002] The cyanide gold extraction process is widely used in the field of gold production, such as "raw ore → ore grinding → cyanide → zinc powder replacement" and "gold concentrate → roasting → cyanide → zinc powder replacement" and other production processes produce a large amount of Cyanide barren solution, most gold production enterprises conduct closed-circuit circulation on cyanide barren solution, and heavy metal ions such as copper and zinc in the barren solution gradually accumulate, which will lead to low recovery index of gold extraction by cyanide and increased consumption of sodium cyanide , seriously affecting normal production. [0003] In order to realize the re...

AI Technical Summary

Problems solved by technology

The two-step precipitation method is represented by the "acidification precipitation method for treating cyanide-containing wastewater" disclosed in Chinese patent CN1144194A. It includes two processes of acidification precipitation and neutralization precipitation. The pH values ​​of the two processes are respectively controlled at 1.5-2.5 and 9.5- Within the range of 10.5, some impurities in the poor cyanide solution can be removed, and cyanide and some valuable metals can be recovered, but zinc cannot be effectively removed, so that the accumulation of zinc in the poor cyanide solution will affect the cyanide gold extraction index and other deficiencies; The three-step precipitation method is represented by the "three-step precipitation treatment process for cyanide-containing barren solution" disclosed in Chinese patent CN101386454B. It is optimized on the basis of the two-step precipitation method, and a zinc removal precipitation process is added, that is, acidification precipitation, Zinc removal precipitation, neutralization precipitation, the three processes control the pH value in the range of 1.5-3.0, 5.5-6.5 and 10.0-13.0 respectively. The three-step precipitation method makes up for the shortcomings of the two-step precipitation method that cannot effectively remove zinc, but its existence The process involves three solid-liquid separations, narrow range of process parameters for zinc removal pH control, inconvenient operation, and imprecise control.

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