Study on the feasibility of reusing the tailings of Huangyan Lead-Zinc Mine

There are 1#, 2# and 3# tailing ponds in Huangyan Lead-Zinc Mine, with several important villages and drinking water sources downstream of these three tailing ponds. Huangyan Area in Zhejiang Province belongs to the frontier area affected by typhoon. Although the three tailing ponds have been closed for many years, there are still potential safety hazards and inherent risks. Only by comprehensively utilizing or removing all the tailings in the tailing ponds, and restoring the original landform after dismantling the initial dam, flood discharge facilities and other tailing facilities, can the inherent safety risks of the tailing ponds be eliminated from the source and the safety of the surrounding environment be improved. Therefore, the problem of resource utilization of tailings should be solved first. There are some valuable lead-zinc minerals in the tailings of Huangyan Lead-Zinc Mine. Through the experimental study of differential flotation, isoflotability flowshee and bulk flotation, a relatively good separation index can be obtained through differential flotation. When the tailings with grinding fineness is −0.045 mm accounting for 85%, a lead-zinc mixed concentrate with yield of 1.74%, lead grade of 22.42%, zinc grade of 32.35%, lead recovery rate of 67.63% and zinc recovery rate of 57.99% is obtained through the closed-circuit process of bulk flotation, that is “the coarse concentrate is checked twice for refinement and screened once after re-grinding”. The experimental study on the production of autoclaved aerated concrete from the tailings of Huangyan Lead-Zinc Mine is carried out, and the best raw material formula and technological conditions are explored. Autoclaved aerated concrete is produced by using lead-zinc tailings as the main raw material, and the products with absolute dry bulk density B06 and strength grade A3.5 are obtained in the laboratory. The research shows that the tailings of Huangyan Lead-Zinc Mine can be used as the siliceous material for producing autoclaved aerated concrete. Combined with the market research on local usage of tailings, through scheme demonstration, the best utilization scheme of tailings is found out, which provides technological ideas and market direction for the next step of recovery and sales of tailings.