Effects of volatile organic compounds on the explosion characteristics of polyethylene dust

Abstract

This study investigated the effects of different concentrations of ethylene and propene gas on the explosion characteristics of polyethylene (PE) dust. After the addition of ethylene and propene gases, the maximum explosion pressure of PE dust increased from 6.7 barg to 9.1 and 7.6 barg by 1.4 and 1.1 times, respectively. Furthermore, the lower explosion limit (LEL) decreased; the addition of even a small amount of these inflammable gases was sufficient to produce a hazardous gas/dust hybrid mixture with low LEL. PE dust tests in a 2 vol. % propene environment revealed that an initial explosion occurred in the hybrid gas mixture, and the heat was transferred to the remainder of the incompletely mixed gas/dust mixture, thereby leading to a two-stage and more complete reaction. In addition, 2 vol. % propene tests also exhibited changes in the maximum pressure rise rate increase, resulting in strong St-2 level explosions because the propene reached its LEL of 2 vol. %. Therefore, propene underwent a complete combustion, resulting in a higher rate of pressure, and shortened time to maximum rate of pressure rise (TMRPR). Thus, the use of volatile organic compounds in dust manufacturing processes considerably increases the risk of explosion incidents.