Abstract:

In order to extend the service life of the tailings pond and treating the goaf，it is urgently

necessary to carry out experimental research on phosphate filling in Jinsha phosphate mine，providing basic

data for the process design of the backfill system. By sampling of filling materials，the physical and chemical

properties parameters of phosphate tailings were tested and analyzed. Based on the flow performance，bleed⁃

ing rate，and filling ratio test of the filling slurry，the influence of factors such as filling concentration and

sand-ratio on the mechanical properties of the backfill was comprehensively determined. Furthermore，the

strength growth mechanism of the backfill was analyzed by SEM-EDS microscopic test method. The main

reason for the strength growth of the backfill was that the cement hydrated to form fibrous C-S-H gel，over⁃

lapped with fine tailings particles to form a whole，and filled the internal pores of the specimen. The re⁃

search results can provide reference for determining the cemented filling parameters of tailings in similar

phosphate mines in China.

Key words:

phosphate tailings, cemented backfill, fluidity performance, bleeding rate, backfill

strength