A Study Of High Density Total Tailings Backfill Technology In Huangmei Phosphorus Mine

After years of phosphate mining in Huangmei, as there is no method of mining used properly, neither effective treatment in goaf of mining, parts has generated a large area of subsidence and collapse. At the same time, the concentrator tailings of phosphate ore, which annually productivity is55～60%, are poured into the tailings reservoir directly and the capacity have been saturated. The worse, tailing seepage water which has come to the lower reaches of the mine has an enormous impact on the lives of the residents. In order to solve the above problem, based on the specific situation of Huangmei phosphate mine, we came to the study of technology, the key of which is the study of high density tailings backbackfilling technology.By field research, literature search, laboratory testing, process design, and integrated means, we have the in-depth analysis and research of total tailings backfilling ratio of Huangmei phosphorus mine and backfilling system programme design and the mining field backfilling technology. The main research results and conclusions are as following several aspects:(1)By the investigation and the analysis of geological conditions of mine engineering, hydrological geological conditions and the mining status, and evaluation of the existing mining method, determination has been reached that total tailings cemented backbackfilling of horizontal layering method fit Huangmei phosphorus mine.(2)By backfilling material Proportioning laboratory testing, on physico-chemical properties analysis of backfilling materials, and ultimately determines an optimal combination of backfilling ratio. Results show slurry density of78%, the first step, pillar with lime-sand ratio of1:8slurry backfilling, and compressive strength1.73Mpa,28days later. The second step, stope uses non-cemented total tailings backfilling, compressive strength, the28days later, of which is0.24Mpa. The thick of Adhesive surface is20cm. And lime-sand ratio of each layer is1:6and the compressive strength,28days later, is2.55Mpa. It got the flow feature experimentation of the optimized proportion slurry, to determine slump, diffusibility, which show that the optimized proportion slurry with good performance of transmission, meet the requirements of pumping transportation requirements. (3) Through the design of high density tailings backfilling system in Huangmei phosphate mine with large stowing gradient, industrial filliing pump is applied to pressure transmission backfilling slurry and make sure the reliability and stability of pipeline transportation system.(4) Selection test of Stope is at Ⅱp phosphate layer,which locates the level of160meters, between the exploration lines10～11, where the upward horizontal slicing and filling as industry tests happens.we have the comprehensive analysis by the field test on water treatment technology in Stope, sealing technology of Stope backfilling and pipeline laying technology of Stope backfilling.(5) The total investment of the backfilling system is3.4715million yuan. The cost of integrated ore mining is73.65yuan per ton. After the promotion of backfilling method, recovery rate can reach80～85%. Mine service life can be extended7or8years, and the output value will add up about2.03-2.25billion yuan, economic benefits of which are obvious. While it addressses the issues like the tailings stacked the covering ground, tailings management, and environmental pollution, which provides an important safeguard to achieve comprehensive sustainable development of mine.