Dust Reduction Capabilities of Five Commercially Available Bag Valves

摘要

The dust-reduction capabilities of five commercially available bag valves were evaluated by the Bureau of Mines for use in mineral processing plants. The five valves were made of (1) standard paper, (2) polyethylene, (3) extended polyethylene, (4) double trap (paper), and (5) foam. The valves were evaluated at a mineral processing plant during the bag loading, conveying, and pallet loading process. For the overall process, the extended polyethylene valve was the most effective at reducing product blowback, and resulted in lower dust concentrations for bag-generated dust. When compared to the standard paper, it gave a 62-pct reduction in respirable dust at the bag operator location, and a 66-pct reduction at the bag stacker location. The cost of the extended polyethylene valve is less than 1 cent per bag higher than that of the standard paper valve. The high dust reductions and slight cost increase make it an attractive choice for the mineral processing industry.