The Wengfu Phosphate Datangpo Mine Paragraph Mining Method Parameters Optimized

Sublevel drilling-stage room and subsequent filling mining method is suitable for caving the mid-steady, inclined-steeply, mid-thick-thick ore body and surrounding rock. The mining methods have some sections such as sub-developing, sub-drilling, stage extracted ore, mining ore room by stage and subsequent filling. This method not only can effectively control the ore boundaries, flexibility and strength, but also has small ore loss. So in recent years it becomes widely accepted and has been applied in many iron ore and non-metallic mine.DaTang ore in WengFu phosphate mine is mid-steady inclined-steeply belong to moderate steady and inclined thick solid ore body (a seam, G sandwich, b seam referred to as ore body.).Above 920 mid-stage of Datang ore block, the exposed surface serious weathers. So it used the sub-caving and the body back mining method.According to statistics, during the production of the mine caving, the integrated recovery is 65% and dilution rate is 27.6%. Obviously this method goes with high ore loss ratio and dilution, indelibility surrounding rock, and the ore grad adjustment is difficult to manage.This matter seriously affects the overall economic benefits of mining.In order to eliminate the middle 850m stone G layer, clamp allocate the proportion of a and b layer, improve ore mineral recovery and achieve good economic benefit, we put forward the Sublevel drilling-stage room and subsequent filling mining method after many research.In the established mining methods, reasonable mining structural parameters played a crucial role on mine safety production and economic benefits.This article studies the geologic report and summarizes the production practice and estimates the rock quality grading index. Then it takes the quality grading index for main basis, and uses Hoek-Brown to study rock mechanics parameters. To get better stope structure parameters, this article uses Flac3D to simulate three stope structure parameters schemes. According to the ore mining technical conditions, we numerical analysis simulates the decoration in the condition of keeping the mine height, and keeps the step ore 20m width, two-step ore 10m, step ore 20m, two-step ore 20m, step ore 30m,two-step ore 30m. According to simulate the stress distribution, stress concentration position, maximum tension stress, maximum compressive stress and the position and shape of the plasticity, we get the best size. They are:the room is 70m height(including the bottom construction), the length of room is the thickness of ore, step ore is 20m width, two-step ore is 20m width, the pillar is 10m height. Under the structural parameters, the room is safer, and the size of stope is bigger and it is better for mining and fits the mining technical conditions. The industrial tests indicate that the recovery rate will increase from 65% to 90.6% and the impoverishment rate will deduce from 27.6% to 7.21%, if we change the mining method to filling ore room method. The method can get better economic benefits. The result indicates that the new scheme fits this mine and the parameters are reasonable, it can increase the recovery rate, reduce the impoverishment rate. At the same time, the research result can offer reference for similar mines.