Effect of the Indigenous Microbial Community on Coal Flotation

Abstract

The indigenous microorganisms might have great potential to influence coal flotation, however, have never been emphasized. This study focused on the relationship between indigenous microorganisms, flotation efficiency, and pulp physicochemical properties in a coal beneficiation plant. The results showed that the microbial community in the coal flotation system had high diversity (Shannon index ranged from 6.38 to 7.38). The microorganisms were endogenous from raw coal and persisted in the flotation system with dominant taxa including Proteobacteria and Acidobacteria . The community structure of indigenous microorganisms changed with the addition of flotation reagents, especially nitrogen-containing reagents, which might be the key factors shaping community structures. Most bacteria were demonstrated by Spearman correlation analysis that had negative impacts on the flotation performance (ash content) of coal, except for Nitrososphaera . It is the first study to concentrate on the performance of indigenous microorganisms in coal flotation systems, providing guidance for the optimization of coal flotation from the perspective of microorganisms and contributing to the efficient usage of endangered energy sources.

Keywords: Coal flotation, Indigenous microorganism, Ash content, Reagent, Microbial community structure