Process Safety and Environmental Protection, Vol.109, 357-364, 2017
Experimental study on the dust filtration performance with participation of water mist
To study the influence of water mist on the dust filtration performance, a lab-scale experimental dust collector system was built and tested for dust laden air filtration pressure drop and dust emission concentration during the collector operation with a water mist spraying rate of 0-3200 mL/h. Next, filtration performance was evaluated and the morphology of dust deposition on the filter was analyzed. Moderate water mist was found to be beneficial in decreasing pressure drop, prolonging the filtration cycle, reducing the dust emission and improving the filtration performance. Conversely, an excess water mist accelerated the pressure drop increasing rate, raised the filter cleaning frequency and decreased the filtration performance. Additionally, the influence of water mist on the filtration performance was found to be mainly due to the changing of filtration pressure drop. The dust deposition morphology analysis showed that a moderate water mist brought a more open dust cake, and thereby led to the decrease of pressure drop; whereas an excess water mist gave rise to the liquid bridge in the cake, leading to the increase of pressure drop. (C) 2017 Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.
Keywords:Coal dust;Dry-type filtration;Water mist;Liquid bridge;Dust cake structure;Deposition morphology