Author(s)

Yueqi Shi, Changhong Li, Zhiwen Song and Peng Liu

Corresponding Author

Yueqi Shi

ABSTRACT

Due to the continuous improvement of the beneficiation process, the grain size of the tailings sand is decreasing day by day. The proportion of the total tailings of many mines below the 74um particle size exceeds 50%, These pose new challenges to the stability of the tailings sand during the storage process.. This paper takes the tailings sand of Chenkeng tailings reservoir area under the pit of Mukeng Mining Company as the research object, and selects the different ratios of cement cement, fly ash, blast furnace slag and desulfurization gypsum as test variables. For the experimental variables, the curing orthogonal test was carried out to comprehensively analyze the effects of various levels on the solidification effect of tailings sand. The results show that: (1) the cohesion and internal friction angle of the sample after 7 days of curing In terms of comprehensive consideration of the main influencing factors of the two, the best curing agent ratio is 3% of cement clinker, 1.5% of fly ash, 2% of blast furnace slag, and 1% of desulfurized gypsum. After the agent, the cohesive force of the ultrafine tailings sand is raised from the original 27.00 kPa to 50.53~161.94 kPa, and the internal friction angle is raised from the original 25.53° to 29.41~35.58°. The solidified tailings sand sample Cohesion and its uniaxial compressive strength There is a certain positive correlation between degrees. (2) When the content of curing agent is between 4.5 and 7%, the permeability coefficient of the cured sample will continue to decrease, but the decreasing trend will gradually slow down. The permeability coefficient of the sample after curing was measured to be between 5.00×10-6~1.61×10-5 cm/s.

KEYWORDS

Ultrafine tailings, solidification, orthogonal test, strength characteristics