A new small-scale dust cloud minimum ignition energy apparatus

Abstract

Dust explosions pose a serious threat to safety and capital in many process industries. The proper management of this hazard is partially reliant on accurate ignitability data for flammable dusts. The minimum ignition energy (MIE) of a dust is one such quantification, which quantifies the likelihood of ignition for a flammable dust based on experimental evidence. Since the industrial revolution, many experimental methods have been developed for testing the MIE of ignitable dusts. This manuscript presents a novel, small-scale device for testing dust cloud MIEs. This device was designed to be modular and to easily integrate into the existing hardware of the popular Kühner MIKE3 MIE testing device. Since the Kühner MIKE3 is a well-trusted device that produces repeatable MIE results, the new small-scale device was designed specifically to return comparable MIEs. The device was designed to create a dust dispersion similar in dynamics to those of the Kühner MIKE3, such that ignition behavior in the two devices would be similar. A novel technique of using high-speed video to holistically analyze in-tube dust dispersions is presented. Experimental data from the video technique was used to optimize the dispersion dynamics in the small-scale device. Functionality of the small-scale device was verified by the testing of three control dusts in both the new small-scale device and the MIKE3, with MIE results in agreement for each dust. The small-scale device presented in this work is fast and simple to operate and requires much less sample than traditional MIE testing methods. These features make it ideal for testing expensive or hazardous dusts., or dusts for which sample quantity is limited.