Today, Xiao Bian will explain to you what are the pre-treatment methods for filling aggregates in tailings paste filling station?Filling aggregate, we also call tailings, referred to as tailings, tailings before filling, in order to avoid pollution of groundwater, we must first concentrate to the required concentration.
Concentration value: depending on the filler gradation composition and density, coarse aggregate mass concentration is high, but for fine materials, the concentration of about 60% can reach the paste state.
Concentration methods are divided into three types: horizontal sand silo natural filtration, vertical sand silo flocculation concentration, deep cone thickener dynamic concentration. (Figure below)
1. Natural filtration of horizontal sand bin
2. Flocculation and concentration of filling aggregate
3. Dynamic concentration of deep cone thickener
Pre-treatment of filling aggregate:
The vertical sand bin was first used for classifying tailings. For the whole tailings, due to the slow settling speed, the sand concentration in the vertical sand bin is unstable and the overflow water is muddy.
For example, the feed concentration of vertical sand bin of a tungsten ore is about 30%, while the solid content of overflow water reaches 20%, and the concentration effect is poor. After that, a deep cone thickener is used.
The deep cone thickener is added with a mechanical rake frame system, with large diameter, long concentration time and stable sand release. But to prevent the filling during the suspension of the pressure rake accident.
Is the tailings directly concentrated in the vertical sand bin or deep cone thickener or is it initially concentrated by the high-efficiency thickener before entering the vertical sand bin or deep cone thickener?
The lower the concentration, the faster the sedimentation rate. If the tailings can flow into the vertical sand bin or deep cone thickener by itself, it is recommended that the tailings not be concentrated by the thickener (the concentration of sand supply is preferably 15%; If pumping is required, in order to reduce the energy consumption of tailings transportation and backwater, it can be concentrated to about 40% by a high-efficiency thickener, then diluted after entering the vertical sand bin or deep cone thickener.
Note: For the above documents, please refer to the PPT of Zhang Qinli's speech by the Mining and Metallurgical Research and Design Institute of Hunan CUHK Design Institute.
