Determination of Explosion Venting Requirements for Municipal Solid Waste Shredders

摘要

A gas explosion test program has been conducted in a realistic full-scale mock-up of a municipal solid waste shredder. The 2200-cubic feet mock-up simulates a horizontal-shaft hammermill (including rotating shaft, discs, and hammers, but without trash) with a large inclined feed hood. Varying amounts of propane have been injected into the shredder and the resulting gas concentrations generated by rotor-induced mixing have been measured. Eight propane explosion tests have also been conducted with varying volumes of near-stoichiometric propane-air mixtures and various hammermill shaft speeds. Test results indicate that venting through the top of the shredder effectively keeps pressures under 6 psig (41 kPa) at shredder shaft speeds of 250-660 rpm and 16 hammers, but allows pressures to reach 10-15 psig (69-103 kPa) at a shaft speed of 900 rpm with 48 hammers.