Effect of CaCl₂, Al(OH)₃ and NH₄H₂PO₄ on the explosion sensitivity of pulverized coal

ABSTRACT

In this paper, the effects of 30 wt%, 50 wt% aluminum hydroxide, calcium chloride and ammonium dihydrogen phosphate three explosion inhibitors on the two sensitivity parameters of the minimum explosion concentration and the minimum ignition energy of pulverized coal were investigated. It was found that for the same explosion inhibitor, the higher the content of explosion inhibitor, the higher the increase of MEC and MIE of pulverized coal-explosion inhibitor. At the same time, dust reduction measures should be taken in time when the coal dust concentration will be close to 70 g/m³. It was found that for the same explosion inhibitor, the higher the content of explosion inhibitor, the higher the increase of MEC and MIE of pulverized coal-explosion inhibitor. In the meantime, dust reduction measures should be taken in time when the coal dust concentration will be close to 70 g/m³. Furthermore, 150 g/m³ was the critical concentration of the ignition energy of pulverized coal. In order to prevent the occurrence of coal dust explosion accidents, it was necessary to resolutely prevent the concentration of pulverized coal from approaching this value on site. In addition, when the pulverized coal-explosion inhibitor concentration was 100 g/m³-250 g/m³, whether it was 30 wt% NH₄H₂PO₄ or 50 wt% NH₄H₂PO₄, the ignition energy required for mixing with pulverized coal was greatly increased. Overall, in the concentration range of 30–50 wt%, 50 wt% NH₄H₂PO₄ was more advantageous in the suppression of coal dust explosion.

KEYWORDS:

• Minimum explosive concentration
• minimum ignition energy
• explosion inhibitor
• explosion sensitivity
• explosion prevention

Disclosure statement

No potential conflict of interest was reported by the author(s).

Supplementary material

Supplemental data for this article can be accessed online at https://doi.org/10.1080/15567036.2022.2077862

Additional information

Funding

This work was supported by the Fundamental Research Funds for the Central Universities [2021YJSAQ18].

Notes on contributors

Jiangshi Zhang

Jiangshi Zhang is a professor in China University of Mining and Technology-Beijing, his main research direction is dust control and safety management.

Xiaofeng Ren

Xiaofeng Ren is a PhD student in China University of Mining and Technology-Beijing, his main research direction is dust control and dust explosion.

Yanhui Wang

Yanhui Wang is a master student in China University of Mining and Technology-Beijing, his main research direction is dust control.

Jianhua Liu

Jianhua Liu is a master student in China University of Mining and Technology-Beijing, his main research direction is dust control.

Lei Fang

Lei Fang is a PhD student in China University of Mining and Technology-Beijing, his main research direction is dust control.