Abstract: The unclassified tailings flocculation sedimentation technology is the key technology of filling slurry preparation in filling mining.In order to study the flocculation sedimentation law of unclassified tailings in Yinzhushan Lead-zinc-silver Mine，the static and dynamic flocculation sedimentation test was carried out，and the orthogonal test and data fitting research method were used to analyze the influence of flocculant，whole tailings concentration and feeding speed on the flocculation sedimentation of unclassified tailings.The results show that the optimum type selection of flocculant is 12 million molecular weight APAM，the optimum concentration of flocculant is 1.354‰，the optimum mass concentration of total tailings is 25.162%， the optimum unit consumption of flocculant is 37.925 g/t，and the optimum feeding speed ( dry tailings ) is 0.7 t/(m²·h).The test results can provide technical support for the selection of thickener in this mine.

Key words: unclassified tailings, flocculation sedimentation, flocculant, numerical fitting