Patent ID: 7819253

Claim:
An improved filtering flow box having a floor, two side walls, a rear wall, an inlet port, at least one feed-line port, a removable filter, and a mounting flange extending from a periphery of the inlet port that is configured to engage a conventional silo outlet port, the improvement comprising: (a) an entry wall extending from the floor at an angle in a range of about 120 degrees to about 150 degrees, the entry wall being opposite the rear wall and intermediate the side walls; (b) at least two filter guides extending from the side walls into the filtering flow box for removably holding the filter intermediate the entry wall and the rear wall at an angle in a range of about 30 degrees to about 60 degrees relative to the floor; and (c) a filter access port adjacent an edge of the filter for allowing access to the filter, wherein the filter slidably engages the filter guides, each of said at least two filter guides comprises an elongated upstream rail and an elongated downstream rail, wherein the rails are parallel to one another and spaced apart from one another to form a channel therebetween, and wherein an edge of the filter slidably fits within each channel.