Abstract: A modular dust collection and filtration apparatus including a housing forming a primary inertial and gravitational separation chamber and including first and second dust collection hoppers. A vertically extending duct is disposed in the housing and extends through a partition separating one of the hoppers from the primary separation chamber. A porous media filter element is disposed in the duct at the upper end thereof. A removable tower section of the housing is disposed around the duct to form flow passages leading to swirl vanes which introduce the flow stream into the duct. A reverse jet cleaning system includes repeat cycle timer controls for periodic reverse jet cleaning of the filter elements at different times to reduce impedance to air flow through the apparatus.