Study on Filling Pipeline Optimization Based on Full Pipe Transportation
Mine filling technology is an important technical means for the construction of green mines,and full pipe transportation is a very important technology in the filling operation of underground metal mines.Full pipe transportation can minimize the contact area between filling slurry and air,reduce the impact on the filling pipeline,extend the service life of the filling pipeline,and improve the efficiency of mining filling operations.Aiming at the problem of the long distance between the newly discovered edge ore body and the filling station in Fankou lead-zinc mine and the high difficulty of transportation,the surface pipeline SL1 and underground pipeline L2-2 in the mine design plan were selected as the research objects to study the optimization plan of the filling pipeline in Fankou lead-zinc mine.Firstly,using theoretical formulas and based on the filling data of Fankou lead-zinc mine,the filling line and full pipe rate of SL1 pipeline and L2-2 pipeline were calculated when transporting graded tailings and fine tailings,respectively.The comparison was made using the optimal full pipe rate of 0.8 as the standard.The results show that both pipelines are in a state of under pipe when transporting graded tailings,and are in a state of over pipe when transporting fine tailings,which do not meet the optimal full pipe rate and need optimization.Secondly,through formula derivation and calculation,the ideal horizontal pipe diameter and the hydraulic slope after diameter change when transporting different slurry were obtained.Finally,numerical simulation was used to verify the calculation results of pipe diameter optimization.A pipeline model was constructed using CFD.The vertical pipeline was taken as 5 m,the horizontal pipeline was 23 m,the total length of the pipeline was 28 m,and the curvature radius at the bend of the pipeline was 0.55 m.The horizontal pipe diameter was changed.Fluent software was used to simulate the full pipe transportation before and after the diameter change,and key data such as flow velocity and full process resistance were obtained when transporting graded tailings and fine tailings.By comparing and analyzing the pressure of the pipeline and the maximum outlet flow rate,it is concluded that SL1 and L2-2 can transport graded tailings by gravity after optimizing the pipe diameter,while fine tailings can't be transported by gravity.However,the pumping pressure is significantly reduced,so the calculation results are reasonable.Therefore,this optimization plan is relatively reasonable and has strong guiding significance for mining filling operations.