The Mining Technology Optimizing Research Of Remnant Orebody With Remnanted Old Workings

The remnant orebody with remnanted old workings mining is a quite complex engineering. Supported by Hunan science & technology planned project-The research of Synthesized recyclation technology and two transverse subjects and combined to the actual condition of the remnant orebody mining with remnanted old workings of Hunan XinLong limited liability company, by use of the research methods of fuzzy optimal, academic analyze, numerical simulation, field experimentation validation, this paper conducted research on some issues about the mining technology optimizing of XinLong remnant orebody with remnanted old workings.According to the mining technology condition, it chosed four representative mining plans-Pillarless sublevel caving system, layer falling mining, mining method of downward slice and consolidated fill and Ming with fringedrift and Roadways across the vein. Turned the diversified fuzzy or subjective factors to numerical species, it quantificated and analyzed the evaluating indicators of the four mining plans and enduced the best mining plan to the mining with fringedrift and Roadways across the vein.The ore's activity during the process of ore drawing is the typical flowing of loosening body. Based on the former research of the loosening body activity discipline, it numerically simulated the ore's activity by computer and found out diversification of the loss ratio and coefficient of recovery under the different height of lift and the different millhole width between centres. The result indicated that the ore's coefficient of recovery obviously decreased with the widening of the millhole width between centres and the ore's loss ratio obviously increased with the heightening of the height of lift. In order to advance the coefficient of recovery and depress the loss ratio, it should minimize the height of lift and the millhole width between centres, but that would increase the quantities and cost. So there should be a reasonable height of lift and a reasonable millhole width between centres.After the underground ore mined, the upside rock is out of support. The rock body inner stress original equilibrium state was broken. The rock body internal stress was redistributed. The rock beside the goof was displaced, distorted and broken. It simulated the ore and wall rock stress condition of the two mining sequence by computer and made sure that the forward mining sequence was better than the backward mining sequence. The reason was that from view of the control situation of the roof the entire process of inter-charged was relatively stable and conducive to the stability of the roof control in forward-mining sequence, from the view of the safety of roadway excavation wearing clock roadway excavation environmental stress superposition were relatively uniform and won't cause major security problems in forward-mining sequence, from the view of the ore drawing conditions and ore loss rate, the no mining and supporting ore of the former four-mining step was released at the fifth step, and the Loose ore would likely be a large agglomeration of compaction and ore conditions would worsen and the loss rate was increased.Residual mining security issues generally included security problem in the mining process and the destruction of the surface environment after mining. Based on the investigation of the current main problems of domestic remnant ore mining, it analyzed the security technology problem in the mining process, proposed several effective solution in light of these problems and provided an effective guarantee for the mining safety production.