Novel technology for synergetic dust suppression using surfactant-magnetized water in underground coal mines

Coal dust is an increasingly serious problem in underground coal mines. This research developed and tested a novel dust prevention technology of surfactant-magnetized water that utilizes the synergy between magnetization and surfactants to markedly improve the wettability of water, resulting in better dust suppression than water sprays alone. The technology was systematically studied in laboratory and field conditions. A compound surfactant was developed as part of the new technology and was effective at low dosage (0.03 wt%, approximately one-sixth that of conventional alternatives). The new surfactant exhibited excellent synergetic effects with magnetization, with reduced surface tension (28.07 mN m(-1), 7.2% lower than that of the original solution). A new type of magnetic apparatus was designed and formed the core of the novel dust suppression technology. The magnetic device produces a powerful and consistent magnetic field (300-350 mT) to achieve effective magnetization of water flow. In field tests, the new technology increased respirable dust and total dust suppression efficiencies by 44.94% and 31.79%, respectively, compared to that of water spray. And the new technology effectively improves the atmosphere in mechanized underground coal mines, contributing to a safer and healthier working environment. (C) 2017 Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.