Study on influencing factors of Coal Microbial Flotation Desulfurization

Abstract

This study systematically investigates the influence of various factors on microbial flotation desulfurization of coal, with a particular focus on removing organic sulfur. The parameters examined encompass particle size, pretreatment time, bacteria species, bacterial concentration, forms of sulfur occurrence, ash yield, and coal rank. The study aims to develop a thorough understanding of the desulfurization process and establish a theoretical framework for advancing clean coal technology and efficient coal utilization. Stringent control was maintained over parameters such as particle size, pretreatment time, bacterial species, and bacterial concentration. Various forms of sulfur and coal rank were considered to evaluate their impact on desulfurization. Correlation analysis was conducted to investigate the relationship between ash yield reduction and the extent of desulfurization. Thiobacillus ferrooxidans and Rhodotorula mucilaginosa were employed in the experimental setup to assess their efficacy in microbial flotation desulfurization. The results demonstrate that microbial flotation desulfurization achieved the highest removal efficiency for organic sulfur, reaching 79.65%. Notably, the desulfurization of organic sulfur exhibited an increasing trend with decreasing coal rank. Correlation analysis reveals a positive correlation between ash yield and desulfurization, suggesting that high mineral matter content in coal facilitates microbial flotation desulfurization and enhances biological oxidation. Comparative analysis of single strain and mixed strain experiments revealed varying degrees of improvement in desulfurization extent, with the mixed-bacteria system exhibiting the most effective removal of organic sulfur, which suggests that Rhodotorula mucilaginosa can significantly enhance microbial flotation desulfurization. Overall, this research provides systematic insights into the influence of process conditions and geological factors on coal desulfurization. The study establishes a theoretical foundation for the development of clean coal technology and the efficient utilization of coal resources, contributing to the advancement of environmentally friendly practices in the coal industry.