Article: Advantages Of Cleaning Without A Venturi In Pulse Jet Baghouse Collectors

By Brian Mathews, Project Engineer, Scientific Dust Collectors

A venturi has been associated with reverse pulsejet baghouse dust collectors since the 1950's, and has become the industry standard design for the reverse-jet cleaning system of baghouse dust collectors. While the reversejet with venturi does provide some advantages when compared to other methods such as reverse-air or mechanical-shaker cleaning systems, the venturi itself has some disadvantages that are often overlooked. The reverse-jet cleaning system with venturi allows for continuous cleaning of the dust collector with almost no moving parts, compared to the reverse-air and mechanical-shaker, which have a significant amount of moving parts. The reverse-jet system utilizes compressed air traveling through an orifice. As the compressed air leaves the orifice, it becomes a jet of air traveling at the speed of sound, Mach 1.0. This jet of air expands under the Law of Conservation of Momentum at a cone angle of about 15° until it is stopped by the throat of the venturi. The typical venturi is approximately 6 inches long, has a throat diameter of 1 ¾", and placed 2 to 3 inches away from the outside of the purge tube (blow pipe).