Dust control system design: Knowing your exhaust airflow limitations and keeping dust out of the system
Designing an effective dust control system starts with controlling dust generation in your process, a topic the author covered in his October 2003 Powderand Bulk Engineering article. This article covers two more factors in designing the dust control system: knowing your system's exhaust airflow limitations and -- contradictory as it seems -- keeping dust out of the system.
A typical dust control system in a dry bulk solids plant includes an exhaust fan, a dust collector, and ductwork leading to one or more dust-controlled openings (that is, capture hoods or enclosures; also called pickup points) at a process's dust sources. In operation, the exhaust fan draws exhaust airflow through each dust-controlled opening to capture dust at the source. The dust is conveyed in the airflow through the ductwork and into the dust collector, where filters collect the dust and the cleaned air is recycled to the plant or exhausted.