Review and prospects of surfactant-enhanced spray dust suppression: Mechanisms and effectiveness

Surfactant-enhanced water spray technology, one of the most economical and efficient dust suppression technologies, is widely used for dust control in mining. Unfortunately, current research on this technology appears to be scattered, and the results do not provide an effective approach for coal dust control. Aimed at addressing this problem by critically reviewing coal dust agglomeration mechanisms and dust suppression effectiveness, this review summarized four steps for droplets capturing coal dust, and two agglomeration mechanisms(immersion and distribution mechanisms) are illustrated based on them. In addition, the dust suppression effect is categorized as either indirect dust suppression or direct dust suppression, depending on the coal dust removal effect. The suppression results show that surfactants can significantly improve the indirect dust suppression, the direct dust suppression efficiency of surfactant-enhanced water spray technology is generally between 80 % and 95 % and can be increased by approximately 40 % compared to the conventional spray dust reduction efficiency, and the suppression efficiency for respirable coal dust (below PM10) is approximately 1 % lower than that of total dust. In the discussion on the challenges and further research directions, relative motion and capture of fine particles, effect evaluation methods and standard, relationship between direct and indirect dust suppression effects, as well as field application technology, are suggested as the main challenges and directions for improving the efficiency of this technology.