Study on adsorption and dust suppression mechanism of urease-producing bacteria on coal-soil mixed dust

Air pollution prevention and control is the primary problem faced by coal mines, in which coal and soil dust are the most serious pollution. However, different coal-soil ratios inevitably affect the dust suppression efficiency of microbial dust suppressants. In this paper, the adsorption mechanism of Bacillus X4 (B.X4), a urease-producing bacteria, on different coal-soil ratios dust surface was investigated to clarify the impact mechanism on the dust suppression of microbial dust suppressants. Both scanning electron microscopy (SEM) and adsorption isotherms showed that B. X4 could adsorb on dust surface and the adsorption was single-layer adsorption. The adsorption kinetic indicated that the adsorption was chemical adsorption. With the increase of soil dust content, the better the adsorption and consolidation effect, the better the dust suppression effect. Zeta potential, scanning electron microscope, Energy dispersive spectrometer (SEM-EDS), and X-ray diffractometer (XRD) results all demonstrated that CaCO3 was formed in dust treated with microbial dust suppressants, which could effectively cement the dust and suppress its flying. [Display omitted] •Adsorption of urease-producing bacteria on dust was a single chemical adsorption.•Dust suppression was positively correlated with bacterial adsorption on dust.•CaCO3 was generated to cement dust after adding microbial dust suppressants.