Flameless Venting Devices for Dust Explosions and Experimental Confirmation of their Efficiency

Abstract:

In a closed pulverized coal preparation system, a special device must be installed to vent flames and pressure during unexpected dust explosions. A vent flame arrestor is a key element in this device, which helps prevent a dangerous second explosion by venting flames. Traditional vent flame arrestors are designed with mounting metal fiber or rock fiber on both the sides and the top of the arrestor to cool dust flames and arrest burning dust during an explosion. This type of arrestor is widely used, but their application is still problematic, even for St1 dust at low reduced pressure (Pred). To solve these problems, we designed two types of flameless venting devices. The first is intended for St1 dust explosion venting at Pred 0.07 MPa, and was modified from an original device by adopting a labyrinth-like structure in the interior space to successively reduce the strength of the dust flame. The second is intended for St1 dust explosion venting at 0.07 < Pred 0.18 MPa, and was modified from the first type by adding a special suppressant in the interior space to make the dust flames cooler than the ignition point of the dust. Our experiments confirmed that our designs yield improved efficiency of flameless venting devices, leading to safer vent flame arrestors.

• Periodical: Advanced Materials Research (Volumes 774-776)
• Pages: 340-343
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.774-776.340
• Online since: September 2013
• Authors: Dian Hua Peng, Jian Xing Wu
• Keywords: Dust Explosion, Flame, Flameless Venting Devices, Venting

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