Research on Optimization of the Upper Particle Size Limit of Gangue in Slurry Backfill Based on Interference Settlement

Abstract

With the increasing demand for gangue disposal in China, gangue slurry filling technology, as a necessary technical means for harmless disposal of gangue under low interference conditions, has been widely promoted in Western China, Mongolia, and Shaanxi regions. In order to optimize the upper limit particle size of gangue slurry under interference settlement conditions to ensure the safety of pipeline transportation, the article systematically carried out the gangue slurry characteristics and static settlement test, studied the interference settlement conditions of gangue slurry in the suspension of coarse particles characteristics, and analysis of the gangue particles obtained by the settling speed of engineering verification. The results show that gangue slurry has coarser particles, complex components, and high solid content characteristics, and its static settlement characteristics cannot truly restore the flow state in the pipeline. The particle settling velocity is affected by the concentration of slurry, rheological parameters, gangue particle size, and gangue fine particles of the density of the suspension medium through the mechanical derivation method to obtain the gangue particle settling velocity calculation formula. Moreover, take indoor large-scale tests and field applications for double verification, the upper limit of particle size of 3.00 mm under the condition of the maximum sinking speed of 1.092 × 10⁻⁶ m/s can realize the start with the material did not happen to plug the pipe accident, the field test of the neighboring grouting filling effect is good.