The Alteration And Optimization Of Cemented Whole Tailings Gravity Transport Backfilling System

The application of traditional cemented tailings backfilling technology boosts the development of backfilling technology. However, a series of severe problems come forth as the technology are applied widely: low strength of backfill, long maintenance cycle, low utilization of tailings and regular blocking and breaking of transportation pipes. Based on the theories of Engineering Fluid Mechanics, two-phase hydrodynamics, Computational Fluid Dynamics and pipeline gravity transport, combining the actual situation former vertical sand backfilling system of Hunan province Huangshaping Lead-Zinc Mining Limited Company (Huangshaping Mine for short), the FLOTRAN CFD module of ANSYS was used to build tow-dimension models to reconstruct the pipelines and study the characteristics of pipeline gravity transport systematically. Main research content and results are as follows:1) The pipeline flow characteristics are analyzed. Through the analysis and study of rheological models and solid-liquid two-phase flow, features of gravity fluid transportation are revealed. Related theories and experience formula are referred for parameters determination.2) The mechanism of abrasion and breaking of gravity fluid transport pipeline is analyzed. By analysis of abrasion and gravity transportation mechanism, main factors for abrasion and part-filled pipe flow and the destroying manners of phase transition are obtained.3) Present status of backfilling system is analyzed. The history and evolution of the backfilling system in Huangshaping Mine is set forth briefly, and present status of backfilling system is analyzed including the settings of backfilling station and pipelines underground. The basic character, proportion and mechanics tests of filling material are studied too.4) Problems and alternation schemes of pipeline are studied. On the basis of analyzing the pipeline system of Huangshaping Mine, problems of pipeline system are found and alternation schemes of ground filling station are brought forward accordingly; optimization lay models of filling pipeline are studied and the alternation schemes of underground pipeline are also put forward.5) ANSYS numerical analysis of gravity transportation system. With the basic analysis of gravity transportation system, essential FLOTRAN CFD analysis method is put forward, FLOTRAN CFD module of ANSYS is applied to simulate original gravity pipeline transport system to gain the direct data for abrasion and breaking of pipeline. Numerical analysis is also carried for the alternation schemes and optimization of pipe flow parameters are done as well.