The Application Research Of Phosphogypsum-based Cementing Filling Materials In Huang Mailing Mine

The phosphorus gypsum,which produced from most of phosphate enterprises,is of massive number.Stockpiling method is used to deal with phosphorus gypsum,which not only pollutes environment,but also wastes resources.With the background of the research and mining design of transition from open?pit to underground mining in Huang Mai Ling,this thesis has explored how to use the phosphogypsum?based cementing filling materials made from phosphorus gypsum to fill in the underground mine,and has studied the proportioning problem of filling materials.That will be of great significance for the utilization of phosphate gypsum in the underground mine,and provide a way of solving the problem of resource recycling of phosphorus gypsum.Based on this,the research refers to the research findings at home and abroad about the using of phosphogypsum?based cementing filling materials.By adding different materials and changing the ratio of materials to prepare the slurry,we prepare a mechanical test block,analyse the test results by using the orthogonal test method and establish mathematical models of filling mixture mechanical properties,the slumps and the cost of filling unit.With the ANSYS numerical simulation software,we test the safety mechanical parameters of filling body for underground filling,and combine with MATLAB software to analyse the proportion of materials at the lowest filling cost of the unit,with the constraint conditions of the Mechanical properties of filling body and Slurry slump.The main research results include as follow:(1)In the experiment,7 different materials were added to the filling mixture with slaked lime as a unit mass.The study found that the main factors affecting the mechanical properties of the filling body is only four:the accounting level of mass concentration,phosphorus gypsum,cement and broken rock.The main influence factor of filling mixture slump is the mass concentration,because the more water in filling mixture the better the slump is.The effect of the relative quality of cement on a unit filling cost is the most significant,but the effect of other filling materials on filling cost is not obvious.(2)By using the orthogonal test data,the analysis of the filling mixturemechanical properties,slump constant and filling unit cost was established in different mathematical models.(3)By using the ANSYS numerical simulation software,we calculated the safe value in the actual working condition,2.21 Mpa.Under the precondition of more than 160 mm of filling mixture slump and the adequate intensity of the backfilling,the MATLAB software can be used to optimize the unit filling cost of the filling mixture.When the filling mixture concentration was 75%,the pH of the water mixing was 12.6,the mixing the specific ratio of the phosphogypsum,Fly ash,Waste crushed rock,Lime respectively was 2:3.3:1.7:1,the cost of unit filling was desirable to a minimum at 20.420 yuan/m 3,at the same time the filling strength and the slump parameters respectively was 2.90 MPa and 197 mm.Through theoretical analysis,experiment research and numerical simulation,using the research methods of mathematical modeling,the function models,which refer to strength of filling body,slump constant and unit cost of filling,can be concluded;Under the premises of ensuring the transportation of filling slurry and the strength of the filling body,the ratios of various materials in the condition of the minimum unit filling cost is calculated.The research results have important practical significance for the mining design from open pit to underground mining,and it can provide a solution for other mining enterprises to recycle phosphorus gypsum.