Abstract: In order to effectively control overburden fractures due to coal mining, and protect the surface environments and building facilities, the optimized application of the current super-high water material filling system was studied. Firstly, the effects of surface subsidence reduction by filling with super-high water materials were analyzed. Then according to the shortcomings of the existing filling system technology, the high-speed eddy current pulping system was designed and developed, and the adaptive matching of slurry flow was realized by establishing flow matching model. The optimized filling system was applied to a working face that was filled with super-high water materials. The effects were tested from the strength of filling samples obtained from different sampling sites and the surface subsidence reduction of filling area. The results show that the pulping time the optimized filling system needs is just one-fourth of that the original system requires, that the strength error of filling body samples in different sampling sites is less than 5%, so the pulping effect is stable, and that the amount of surface subsidence is about 78 mm, within the Ⅰ degree damage, which shows that the optimized system has good effect in decreasing ground subsidence.

Key words: backfill mining, super-high water material filling system, reducing surface subsidence, high speed pulping, flow adaptive matching