Organic contaminant removal with no adsorbent recycling based on microstructure modification in coal slime filtration

In coal preparation plants, the tailing coal slime filter cake contains large amounts of super fine particles. It can be hypothesized that the large quantity of organically contaminated water may be purified by a capable filtration process. Meanwhile, the treatment process would be an adsorbent recycling free process, with a roasting process followed in the industry. In this study, methyl blue (MB) was selected as the target organic contaminant, and its removal by filtration was investigated. Meanwhile, the adsorption capacity of MB on Tween-80-modified filter cake was discussed and the spatial structure of the filter was analyzed by micro-CT. With an increasing Tween-80 concentration, the adsorption efficiency of the MB initially increased and reached the maximum adsorption value when the Tween-80 concentration was 60 mg/L, and there was no negative effect on solid-liquid separation. The micro-CT test results indicate that after the modification of Tween-80, the spatial structure of the filter cake was greatly improved, resulting in a relatively stronger adsorption capacity and a higher filtration efficiency. These findings of this study are of great significance for reducing the pollution of water resources and improving the filtration efficiency in the coal washing plant.