Analysis on Physical and Mechanical Properties of Red Mud Materials and Stockpile Stability after Dilatation

Abstract

Red mud is the tailings generated from the production process of aluminum industry and is mainly stacked in open-air at present, so how to ensure the stability of red mud stockpile is very important. Regarding mud stockpile of Guizhou Aluminum Factory as the research object, this paper studies the physical and mechanical properties of Bayer red mud from wetting process, Bayer red mud from drying process, and sintering red mud through laboratory test and finally analyzes its stability under extreme rainfall condition in this region by the Geo-Studio software. The research results show that the red muds in different processes have big difference in physical and mechanical properties. The strength of sintering red mud is about 4.2 times of that of Bayer red mud from wetting process on average, and the strength of Bayer red mud from drying process is about 1.5 times of that of Bayer red mud from wetting process on average. So, the sintering red mud can be used as the subdam of red mud stockpile, to reduce the risk of collapse and dam break. The stability coefficients of the mixed stocking method under three rainfall conditions are 2.611, 2.597, and 2.631, respectively, all of which are above 1.0. It reveals that the dilatation scheme of using the sintering red mud with good engineering properties to stockpile the Bayer red mud is feasible. It can not only guarantee the safety and stability of red mud stockpiles, but also reduce the risk of red mud dam break and the capital investment of red mud yard.