Preparation and performance evaluation of environment-friendly biological dust suppressant

Enzyme-induced carbonate precipitation (EICP) is an economical and eco-friendly technology. The purpose of this study is to evaluate EICP technology for the control of coal dust pollution in open-pit coal mines. A biological dust suppressant was prepared by using urease extracted from soybean. The optimal proportion of biological dust suppressant was determined and the dust consolidation effect of biological dust suppressant was evaluated. The results show that when the volume ratio of urease and CaCl2-urea solution is 1: 3 and the concentration of CaCl2-urea solution is 0.6 mol/L, the precipitation ratio (PR) (83.83%) in coal dust is the highest. Moreover, the mineralization product is calcite-type CaCO3. In the wind erosion-resistance test, when the angle between the air flow and the sample is 0° and the concentration of CaCl2-urea is 0.6 mol/L, the weight loss of coal dust is 2.56%. The corrosive and toxicological properties of biological dust suppressant show that it is non-toxic, less corrosive and weakly alkaline (pH = 7.70). The above results indicate that EICP is a promising coal dust control technology. [Display omitted] •Enzyme-induced carbonate precipitation technology is applied to controlling coal dust from open pit mines.•Enzyme-induced carbonate precipitation is a green and high-efficient dust suppression technology.•The urease activity was high and the precipitation ratio can reach 83.83%.•The coal dust loss in the wind erosion-resistance test is as low as 2.56%.