Study On Two-Step Backfilling Mining In XingLong Phosphate Mine

With the continuous strict requirements of national safety and environmental protection and the development of green mines,filling mining method will be widely used.Continuous mechanized mining,low cost,low loss are the core research topics of filling mining technology.The two-step open-field backfill method is the main mining method for mining medium solid and medium thick ore bodies.The method is divided into two steps,the pillar is filled with cement and the room is not filled with cement,which can maximize the ore recovery rate.How to determine the strength of cementing body scientifically and reasonably becomes the key of backfill.By means of theoretical deduction and numerical simulation,a two-step stoping followed by backfilling mining method is designed for xinglong phosphate mine.Through the three-dimensional numerical analysis of the mining process,the characteristics of ground pressure were studied,and the stope structure parameters and backfill strength parameters were determined.According to the site condition of xinglong phosphate mine,the source of filling material is determined and the material balance is calculated.Carry out mechanical properties research of filling materials and determine the filling material ratio;Design mine filling scheme and establish downhole mobile filling system;To carry out research on mining rapid tunneling technology to improve mining efficiency;The two-step stoping scheme is optimized and the artificial cemented pillar is combined with dry filling to support the cavity.The goaf of xinglong phosphate mine is planned and the goaf of mine is treated according to the test results of filling mining method.Establish safety monitoring system to monitor and control the test stope and goaf to ensure safety.Xinglong phosphate rock in filling mining method is adopted to improve the whole layer after exploration,ore block comprehensive recovery rate reached 87%,test area from11000 tons of ore,more than 75% of recovery rate at the beginning of the design,the technology in xinglong phosphate rock,after implementation,only in a recovery rateincrease,enterprises can more recycling each year 48000 tons of phosphate rock,comprehensive grade of 26%,the average selling price 280 yuan/ton,the enterprise can increase the economic income more than 13.44 million yuan a year,economic benefit is good.At the same time,compared with the original mining method,87,000 tons of resources can be utilized,which accounts for 12% of the annual consumption of resources,and the resource improvement benefits are remarkable.At present,the reserves of the mine are about 10 million tons,and the total amount of resources is expected to be more than 1 million tons,which can create economic benefits of nearly 200 million yuan.