Recycling and harmless treatment method for cyaniding tailing slurry

Abstract

The invention discloses a recycling and harmless treatment method for cyaniding tailing slurry. In the method, the cyaniding tailing slurry containing cyanogen, thiocyanate, heavy metal and arsenic and liquid containing hydrogen peroxide are subjected to direct mixing treatment; the method utilizes high specific surface area of micro-fine granular ore to add the contact opportunity between the thiocyanate and the hydrogen peroxide and the contact area between gas phase and liquid phase through surface adsorption to accelerate a speed of oxidation-reduction reaction and an acidifying and stripping speed, utilizes metallic substances contained in slag to accelerate the reaction rate of the oxidation-reduction reaction without the addition of catalyst, and can reduce cost; meanwhile, in neutralization, Fe3+ in the slag is utilized to meet the requirement of arsenic precipitation without the addition of an arsenic precipitation reagent; when residual cyanides is removed from the hydrogen peroxide liquid, the hydrogen peroxide liquid and cyano complexes which are difficult to remove through the oxidation-reduction reaction form sediment so that the residual thiocyanate is further removed; the method can make the conversion rate of the thiocyanate in the ore slurry more than or equal to 88 percent; and compared with the treatment of filter pressing clear liquid of homogeneous ore slurry, the total reclaiming rate can be increased by over 20 percent.

Description

technical field [0001] The invention belongs to the technical field of mine environmental protection and comprehensive management, and relates to a resourceful and harmless treatment method for cyanide tailings slurry. The method is mainly aimed at cyanided tailings slurry containing cyanide, rhodanide, heavy metal, arsenic and other pollutants. The method uses hydrogen peroxide and cyanide tailings slurry containing cyanide, thiocyanide, heavy metals, arsenic and other pollutants to be treated under different pH conditions, so that the conversion rate of thiocyanate in the slurry into cyanide is ≥ 88%, and cyanide, COD, heavy metals, arsenic and other pollutants meet the requirements of comprehensive sewage discharge standards. Background technique [0002] The cyanide tailings slurry produced by the gold industry and other industries contains a variety of harmful pollutants, among which cyanide, rhodanide (a kind of COD), heavy metals, and arsenic are the main common poll...

AI Technical Summary

Problems solved by technology

However, the natural degradation method and the Inco method have poor treatment effects on thiocyanate, and cannot make the treated tailings slurry press filter liquid meet the COD national discharge standard, and at the same time, the removal effect on arsenic and heavy metals is poor

Although the ozone method can recover the useful substances and has a good treatment effect on the above pollutants, its infrastructure cost and operating cost are high, and the utilization rate of ozone is low. Difficult for industrial application

In addition, there are many methods at home and abroad to treat the press filter liquid containing cyanide, thiocyanate, heavy metals and arsenic tailings slurry, but after press filter, the filter residue containing 20-30% water remains in the tailings pond. There will be safety and environmental risks during the storage process: first, cyanide, thiocyanate, arsenic and heavy metals will still be released when the filter residue is leached by rainwater, polluting groundwater; second, the cyanide released by the leaching of filter residue by rainwater Compounds, thiocyanate, arsenic and heavy metals will cause cyanide, thiocyanate, arsenic and heavy metals in the discharge liquid of the tailings pond to exceed the standard, pollute the ground water, and cause the tailings stock to be a safety hazard. This kind of safety hazard in the rainy season especially serious

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