Particulate filtration system

A particulate filtration system for filtering particulate matter from a gas, the particulate filtration system comprising a filtration unit having a flow path therethrough, the filtration unit comprising:

• a frustoconical-shaped filtration element comprising a first end, an oppositely-disposed second end larger than the first end, an opening in the second end and so as to define a filtration element outlet having a circular cross-sectional area, means for sealing the first end, a frustoconical-shaped exterior surface, a frustoconical-shaped interior surface radially inward from the exterior surface, and a frustoconical-shaped interior cavity between the first and second ends and surrounded by the interior surface;
• a housing enclosing the filtration element and coaxial therewith, the housing comprising a first end, an oppositely-disposed second end larger than the first end, a frustoconical-shaped wall between the first and second ends of the housing, surrounding the filtration element, and having a frustoconical-shaped interior surface radially outward from the frustoconical-shaped exterior surface of the filtration element, an opening in the second end of the housing defining a filtration unit inlet and having a circular cross-sectional area, and means for sealing the first end of the housing;
• an annular-shaped passage defined by and between the exterior surface of the filtration element and the interior surface of the housing and fluidically connected to the filtration unit inlet, the annular-shaped passage having a cross-sectional area that decreases along the flow path in a direction away from the filtration unit inlet;
• and
• an outlet member at the second end of the filtration element coaxial and fluidically connected to the interior cavity of the filtration element, the outlet member defining an outlet passage that is coaxial with the filtration unit inlet and with a shape chosen from the group consisting of frustoconical and arcuate, the outlet passage defining a filtration unit outlet and having a circular cross-sectional area that decreases along the flow path in a direction away from the filtration element and toward the filtration unit outlet;
• wherein the filtration unit inlet, the annular-shaped passage, the filtration element, and the outlet passage define the flow path through the filtration unit and are sized and shaped relative to each other to contour flow through the filtration system by decreasing flow velocity through the filtration element so as to reduce face velocity and reduce differential pressure across the filtration element, and by increasing flow velocity between the filtration unit inlet and the filtration element outlet and further increasing flow velocity between the filtration element outlet and the filtration unit outlet.