Method and device for treating and recycling copper-containing acid wastewater of mines

Abstract

The invention relates to a method and a device for treating and recycling copper-containing acid wastewater of mines. The method comprises the following steps: mixing two wastewaters, namely copper pit water and raffinate, in a certain volume proportion, so as to form mixed acid wastewater; carrying out fractional precipitation on valuable heavy metals in the mixed acid wastewater by virtue of a combined medicament, so as to reduce neutralizing residue and recycle copper; recycling copper in the acid wastewater through the synergic effect generated in a metabolic process of chemical precipitates and sulfate reducing bacteria; and preparing a compound fertilizer from organic sludge generated by virtue of a biochemical method, and reusing the compound fertilizer in the rehabilitation and afforesting of the mines. According to the device for implementing the method, hydrogen sulfide circulating and absorbing equipment is additionally arranged, a reaction device is optimized, and combinedfillers of a bioreactor are optimized, so that the conversion efficiency of sulfate reducing bacteria to SO4<2-> is increased, and the repeated cyclic utilization of hydrogen sulfide is realized. A process adopted in the method is environment-friendly and has good universality to working conditions of the mines, so that the method has the advantages that the recycling rate of copper in the acid wastewater is more than or equal to 92%, the reduction amount of the neutralizing residue is more than or equal to 70%, the storage capacity pressure of tailings can be effectively reduced, and the like.

Description

technical field [0001] The invention relates to the technical field of mineral processing, in particular to a method and device for the treatment and recycling of copper-containing acidic waste water in mines, which is suitable for mineral processing applications. Background technique [0002] A large amount of copper-containing acid mine wastewater (AMD) is produced during the mining process of copper-bearing ores, mainly from: (1) mine acid water containing heavy metal ions in the mine during the tunnel mining process; (2) a large amount of rainwater in rainy areas to sulfide A large amount of acid wastewater is produced on the surface of copper ore; (3) running, running, dripping and leakage of leachate from the heap leaching site during the production process; (4) raffinate is discharged into the sewage pool to become acid mine wastewater. The cost of using traditional lime neutralization method to treat AMD is high, among which the neutralization cost of raffinate treat...

AI Technical Summary

Problems solved by technology

[0005] Chinese patent CN104071945A discloses "a treatment device and method for heavy metal acid wastewater in mines". The device includes a sedimentation tank, a reduction device, a desulfurization device, a PRB device, and a pH adjustment tank. The sedimentation tank is used to precipitate solid impurities in the wastewater Separation treatment to improve the process effect of the subsequent process; the reduction device is used to provide an anaerobic environment for the rapid reproduction of SBR and improve the reduction efficiency of sulfate in wastewater; the desulfurization device is connected to the upper part of the reduction device for effective microbial reduction process Desulfurization treatment is performed on the waste gas generated in the waste water; the PRB device is used to remove heavy metals in the wastewater; the pH adjustment tank is used to realize the pH adjustment of the treated wastewater, so that the pH of the treated wastewater is stabilized within a reasonable range; among them, for the sedimentation tank, reduction device, PRB The device and the pH adjustment pool, each device realizes the orderly flow of liquid between different devices through the sequential water conduit system and the pump system in the water conduit system, but it does not utilize the hydrogen sulfide produced in the SRB reduction process Instead, it is used as waste gas for direct desulfurization treatment, resulting in waste of resources

The whole process can reduce the operating cost by 30-50%, but it will cause the pH value of the multi-stage reflux to be low, which will have an adverse effect on the graded precipitation effect of heavy metals, and the water quality of the wastewater is strictly limited, and the controllability of the process is poor. High COD wastewater as a carbon source failed to further biochemically degrade the effluent from the SRB reactor and treat excess sludge

Images