Spurting NH₄H₂PO₄ Powder to Prevent the Propagation of Gas Explosion along the Duct

ABSTRACT

An active system was designed to detect the flame automatically and spurting out the extinguishing agent to prevent the propagation of flame after gas explosion. The effects of both nitrogen and ABC powder (NH₄H₂PO₄) on explosion prevention were examined. The extinguishant was continually spurted into the duct through the nozzles. At the same time, it was blown downstream by the blast wave. The suppression zone was formed both near and downstream of the nozzles, where distributed the nitrogen and ABC powder with high concentration. By increasing the amount of ABC powder and nitrogen pressure, the flame was quenched and the propagation of explosion was prevented in this region. The influences of upward venting and different nozzle positions were also studied. It is more conducive to explosion prevention with the condition of upward venting than that of without upward venting. The critical amount of ABC powder needed to prevent the flame was proportional to the flame speed at the position of the nozzle. Less ABC powder was required to successfully prevent the explosion when the nozzles were set to the position where the flame speed was lower.

KEYWORDS:

• Methane
• explosion prevention
• nitrogen
• ABC powder
• flame

Additional information

Funding

The work was supported by the National Natural Science Foundation of China [Nos. 51974107, 51674103, 51774059] and supported by the National Key Research and Development Program of China [No. 2018YFC0808103].