Explosion Pressure and Minimum Explosible Concentration Properties of Metal Sulfide Ore Dust Clouds

Yun-Zhang Rao,Yao Yu,Wei Xu,Bo-Yun Yuan,Chun-Yu Xiao,Chang-Shun Tian

doi:10.1155/2020/7980403

Abstract

The explosion pressure and minimum explosible concentration (MEC) properties of metal sulfide ore dust clouds are valuable for the prevention and control of metal sulfide ore dust explosions. In this study, a 20 L explosion sphere vessel was used to investigate the effect of sulfur content, particle size, and concentration on the explosion pressure and minimum explosible concentration of metal sulfide ore dust clouds. Four samples with different sulfur contents were selected (30%–40%, 20%–30%, 10%–20%, and 0%–10%). Before and after the explosion, samples were tested by X-ray diffraction. The results indicate that the metal sulfide ore dust is explosive dust with St1 grade explosion pressure. With an increase in concentration, the maximum explosion pressure increased at first and then decreased. With an increase in sulfide content, the explosion pressure of metal sulfide ore dust increased, while the minimum explosible concentration decreased. As particle size decreased, the MEC also decreased. The sulfur content, particle size, and concentration of metal sulfide ore dust were the main factors affecting the explosion hazard.

Highlights

Metal sulfide ores are widely applied in industrial production of products, such as jewelry, automobile parts, and electronic equipment. e most common metal sulfide ores are pyrite
Explosion pressure and minimum explosible concentration (MEC) are important parameters to characterize the severity of dust explosion consequences. e explosion characteristic parameters of the metal sulfide dust ore clouds were investigated using a 20 L explosion sphere vessel (TD-20L DG, Safety Engineering Research Center of Northeastern University, China; implementing Standards of GB/T 164251996, ISO 6184/1-1985, and ASTM E 1226-2005 [28,29,30]), which comprised a 20 L stainless steel spherical container, a 0.6 L dust container, a dust dispersion system, a pressure detection system, an automatic ignition system, a wireless data transmission system, and a data acquisition system (Figure 5). e explosion chamber was partially vacuumed to 0.04 MPa, and the dispersing air pressure was set to 2.1 MPa [31]
Sample A500 of the ultra-high sulfur group (A) was added because the sulfur content of the ultra-high sulfur group was higher than 30%, which reached the sulfur concentration standard

Summary

Introduction

Metal sulfide ores are widely applied in industrial production of products, such as jewelry, automobile parts, and electronic equipment. e most common metal sulfide ores are pyrite. Erefore, studying explosion characteristics of metal sulfide ore dust is important for preventing and controlling major hazardous accidents in various industries. E risk and strength of the explosion of sulfur dust decrease with increasing particle size [11]. At the same dust concentration, Pmax and Kst all increase with decreasing particle size [14]. For Pmax and (dP/dt)max of sulfur dust, the effect of dust mass concentration is stronger than that of ignition energy, and the effect of ignition energy is stronger than that of particle size [11]. Four metal sulfide ore dusts were investigated using a 20 L explosion sphere vessel to examine the Pmax and MEC of metal sulfide ore dust clouds and factors influencing dust explosion parameters. Comprehensive experimental data and phenomenon analysis of the explosion of sulfide mine dust clouds are provided, and the mechanisms influencing sulfide mine dust cloud explosions are revealed based on existing theories

Materials and Experimental Methods

Results and Discussion

Conclusions e main results of the study are as follows: