ABSTRACT
Design of exhaust systems for dust control poses special problems stemming principally from the need to keep ducts free of settled dust and debris which would impede the flow or air and render the system ineffective. The most common method of design is based on the fact that in most cases dust particles can be prevented from settling in either horizontal or vertical ducts if air velocities are maintained above certain values. Many fine dusts cannot be satisfactorily handled in exhaust systems of conventional design. Arrangements can be readily incorporated into the design of an exhaust system to reject very large inertials when velocities of 2,000 to 3,000 fpm are found adequate for transport of the resulting mixture of fine dust and small inertials. Adjustable blast gates in a dust exhaust system are seldom of value and are usually disadvantageous. When installed, they should be used for "shutoff" purposes only.
