Method for recovering gold and copper from copper ore biological dump leaching tailings

Abstract

The invention relates to a method for recovering gold and copper from copper ore biological dump leaching tailings. The method for recovering the gold and the copper from the copper ore biological dump leaching tailings comprises the following and sequential steps that medium conversion is performed, wherein the waste copper ore biological dump leaching tailings are subjected to three-stage mediumconversion without dump disassembly, the mine alkaline wastewater, with assistance of lime and sodium hydroxide solution, is sprayed to the tailings, and the pH value of the solution flowing from thebottom of a dump is controlled to be greater than 10.5 so as to obtain the medium-converted waste copper ore biological dump leaching tailings; cyaniding spray leaching is carried out, wherein four-stage cyaniding spray leaching is carried out on the medium-converted waste copper ore biological dump leaching tailings, and spraying is carried out by using sodium cyanide solution to obtain a pregnant liquid; and oxidizing and cyanogen breaking are carried out to recover the copper, wherein a cyanide-breaking agent is added to carry out cyanogen breaking and copper removal, cyanogen-broken copper-removed slag pulp is subjected to thickening sedimentation solid-liquid separation to obtain a filtrate and a copper concentrate product, and overflows and the filtrate are mixed and then are adsorbed by activated carbon to obtain adsorbed barren solution and a gold-loaded carbon product. The method has the advantages that the investment is small, the time is short, the cost is low, the gold content of the final tailings is lower than 0.07g / t, the total recovery rate of the copper is higher than 35%, an industrial production line can be formed, the operation is simple, the adaptability is high, and the environmental friendliness is achieved; and the method is suitable for comprehensive recovery and application of nonferrous metallurgy solid waste residues.

Description

technical field [0001] The invention relates to a method for comprehensive utilization of mine solid waste, in particular to a method for recovering gold and copper from copper ore biological heap leaching tailings, which is suitable for comprehensive recovery of nonferrous metallurgical solid waste. Background technique [0002] Gold can not only be used as a reserve fund to maintain currency and economic stability, but also widely used in various fields such as computers, communication equipment, jet engines, electrical appliances, integrated circuits, semiconductor systems and electronic equipment. my country is the largest producer and consumer of gold and copper in the world, but the resource self-sufficiency rate is less than 50%. With the depletion of easy-to-handle gold and copper resources, the contradiction between supply and demand of gold and copper resources is very prominent. A large amount of gold-bearing copper waste tailings exists in the tailings after biol...

AI Technical Summary

Problems solved by technology

At present, this waste copper ore bioheap leaching tailings has not been exploited vigorously. The main problem is that the processing technology of this kind of resources is difficult, because cyanide will reduce the recovery rate of soluble copper mineral gold, increase the amount of cyanide and Increase the cost of subsequent wastewater treatment. In addition, the value of such resources per ton is small. If traditional gold and copper extraction processes such as sulfuric acid leaching of copper + cyanide leaching of gold or roasting acid leaching of copper + cyanide leaching of gold or biological leaching Copper + cyanide leaching gold or pressure oxidation copper leaching + cyanide leaching gold treatment, it is difficult to achieve economically beneficial development, and even the loss outweighs the gain

[0003] In recent years, scholars at home and abroad have begun to study and discuss the comprehensive utilization of waste gold-containing copper tailings, and have achieved phased results. For example, the Chinese patent CN101812587B discloses a "wet leaching method for copper-containing tailings". Add a certain concentration of ammonium salt after the copper-containing tailings are treated with alkali, and then carry out heap leaching and stirring leaching according to the particle size of the copper-containing tailings to obtain a leachate with a high copper concentration, and finally use conventional extraction, electrowinning process or direct Metal copper is recovered by electrowinning, and the solution containing ammonium salt returns to leaching, but this method has the disadvantages of large investment, unfriendly environment and copper resources not being comprehensively recycled; Smelting slag combined with bioheap leaching for comprehensive recovery of gold and copper", this process first crushes copper smelting slag, then wraps low-grade refractory gold concentrate on the surface of copper smelting slag, and builds a heap after the ore particles are solidified. After acid treatment, biological heap leaching is carried out, and the leachate is sprayed circularly. The copper-enriched liquid is recovered by conventional extraction and electrowinning process. The adsorption process recovers gold, but this process exists: the copper blue or other cyanide soluble copper minerals that are not fully leached in the bioheap leaching stage will be leached into the precious liquid in large quantities during the cyanide leaching of gold, and activated carbon adsorption At the same time, gold and copper will compete for adsorption, resulting in many disadvantages such as low gold adsorption rate, high copper content in gold-loaded carbon, low desorption-electrodeposition efficiency of gold-loaded carbon, and cumbersome gold mud purification process.

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