Effects of CaCl₂, Al(OH)₃, And NH₄H₂PO₄ on the Explosion Intensity of Pulverized Coal

ABSTRACT

Herein, the ability of three explosion inhibitors (Al(OH)₃, CaCl₂, and NH₄H₂PO₄) to prevent the occurrence of coal-dust explosions was compared at mass fractions of 30 wt% and 50 wt%. The effects of the three explosion inhibitors on the parameters characterizing the explosion intensity of pulverized coal, such as the maximum explosion pressure, pressure rise rate caused by the explosion, and the explosion index, were investigated. The results demonstrate that with increasing mass fractions of CaCl₂ and NH₄H₂PO₄, the explosion intensity of pulverized coal decreases. Notably, an increase in the mass fraction of Al(OH)₃ did not reduce the explosion intensity. Furthermore, 50 wt% NH₄H₂PO₄ content considerably decreased the values of both the maximum explosion pressure during a single explosion (P_ex) and the maximum rate of explosion pressure rise in a single dust explosion experiment [(dp/dt)_ex]. The maximum decrease in P_ex after adding NH₄H₂PO₄ was observed to be 62.79%, which is 35.87% and 47.70% higher than that obtained after adding CaCl₂ and Al(OH)₃, respectively. Furthermore, the maximum decrease in (dp/dt)_ex after adding NH₄H₂PO₄ when compared with the pulverized coal was 93.07%, which is 10.23% and 45.51% higher than that obtained after adding CaCl₂ and Al(OH)₃, respectively. Therefore, the order of the explosion suppression performance was as follows: NH₄H₂PO₄ > CaCl₂ > Al(OH)₃.

KEYWORDS:

• Explosion intensity
• explosion inhibitor
• explosion pressure
• pressure rise rate caused by explosion
• explosion prevention

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

The work was supported by the Fundamental Research Funds for the Central Universities [2021YJSAQ18]; The NHC Key Laboratory for Engineering Control of Dust Hazard [KLECDH20220101].