Application And Research Of New Slag Based Cementitious Material In The Industrial Test Of Mine Filling

Mineral resources are the material basis of national economic development and social security.At the same time of mining mineral resources,it is inevitable to produce a large number of solid waste.Among them,tailings,as the most harmful solid waste with the largest discharge,will form tailings pond,occupy land resources and pollute the environment if it is not treated effectively.At present,the best way to deal with tailings is to fill the tailings back to the ground as filling aggregate.The traditional filling cementitious material is cement,but the early strength of cement filling body is not enough to meet the current mining and filling cycle speed,and the price of cement is rising,which brings huge filling cost pressure to mining enterprises.In this paper,a new type of slag based cementitious material proposed by the research team of the project team,which can adapt to the current mining and filling cycle speed and replace cement to reduce the filling cost of mining enterprises,is applied and studied in industrial tests.Taking the industrial test of graded tailings filling in a lead-zinc mine as the engineering application background,a series of research works are carried out,such as field investigation,basic theoretical analysis,indoor experiment,sample collection and field industrial test.The feasibility of industrial application of graded tailings filling of slag based cementitious material is verified.The main research contents and conclusions are as follows:(1)Investigate the classification and processing methods of different tailings by mining enterprises,and use XRF,XRD,laser particle size analysis and other methods to analyze the physical and chemical properties of different tailings samples.Based on the analysis of the research and development test results of the new slag-based cementitious material,it is concluded that the quality of the whole tailings is unstable and the water content is high at the current stage,which is not easy to control.The graded tailings is a good graded sand,which is relatively in line with the current requirements of filling equipment and filling technology.It is decided to use the graded tailings as the filling aggregate for the industrial test of fillingnew materials.(2)According to the filling quality of the Mine and the requirements of various indicators,laboratory tests were conducted on the compressive strength and fluidity of this new material filler,cement filler.The laboratory test results show that the new material has a lime-sand ratio of 1:4,a slurry concentration of 76%,and a 3d compressive strength of the filler test block in the laboratory is 3.18 MPa,which can meet the requirements of 3 days3 MPa.The lime-sand ratio is 1:6,the slurry concentration is 74%,and the 28 d compressive strength of the stuffing block in the laboratory is 3.16 MPa,which can meet the requirements of 28 days 3MPa.And the fluidity of the new material filling body is better than that of the cement filling body,and the new material can be filled at a high concentration.The results of the test were analyzed for range and variance,and it was concluded that the two factors,the rubber-sand ratio and the concentration,had a significant effect on the strength and fluidity of the new material filler,cement filler.The influence degree of these two factors on the compressive strength of the filling body is as follows: the cement sand ratio is greater than the concentration;the influence degree on the fluidity of the filling body is as follows: the concentration is greater than the cement sand ratio.(3)The project team successfully set up a new material production line,and introduced the equipment conditions,production processes,and production precautions of the production line.The analysis of the production line silo blockage and powder wall-hanging problem is that in order to avoid such problems,the storage time,temperature,humidity and storage height of new materials should be controlled.It also systematically introduces the industrial test process and precautions of new material filling.(4)The results of industrial sampling on-site sampling show that the new material can adapt to the existing filling system and can smoothly perform filling production.The compressive strength indicators can meet the filling strength indicators of the ore,and have superior fluidity compared to cement.From the indicators of strength and fluidity,the new material can replace cement for filling production.(5)A comparison test of beneficiation of new material fillers and cement fillers was carried out.The test results show that the incorporation of new material fillers and cementfillers will affect the beneficiation,and the degree of influence is basically the same when the amount of the same is the same When the blending amount is 2%,the effect on ore dressing is not obvious.Therefore,if the new material is used as a filling material instead of cement,it will not have a great impact on beneficiation.(6)A comparative analysis of the filling benefits of new materials and cement.New materials can be made stronger and faster than cement by adjusting the filling ratio during the construction period,which is suitable for the current rapid recovery and filling cycle.The use of new materials for industrial filling can achieve both environmental protection and efficient use of solid waste resources,and fully respond to national environmental protection calls,which is of great significance to environmental protection.Compared with cement,the annual cost of filling is expected to save RMB 9.608 million.