Apparatus for fine coal separating water cleaning, and thickening from coal washing waters

摘要

Modern coal preparation plants dispose large quantities of dilute coal tailings what entails socio-economic and environmental problems. By introducing oil and flocculant to these tailings, clean coal and water are recovered, and the amount of solid tailings material to be disposed is reduced. Light oil is used as an agglomeration liquid, and flocculant as a clarification and densification reagent (for rapid settlement). Slurry treated with light oil and flocculant forms three consecutive phases: coal particle micro-agglomerates, clarified water and inorganic material which settles at the bottom. This paper presents a process designed to recover clean coal and washing water by use of oil and flocculant. The results in this work show that up to 60% of the fine coal can be removed from the tailings. This indicates that the proposed method is effective in separating coal from dilute tailings. This process is effectively achieved by simultaneous coal agglomeration, water clarifying, and refuse thickening in one step. In all the experiments conducted, the ash content of coal slimes were drastically reduced which shows the effectiveness of this method.