Cross flow diesel particulate trap

摘要

Cross flow diesel particulate traps are disclosed in which a cylindrical canister contains a plurality of individual ceramic trap elements. The canister is provided with inlet openings along one side and outlet openings along another side which respectively communicate with inlet and outlet spaces formed between individual ceramic trap elements. The traps are provided with inlet and outlet plenums which communicate with the respective canister openings for directing exhaust gases through the canister and for collecting the exhaust gases. In one embodiment, the inlet plenum is divided by partitions into zones and a diverter valve directs regeneration gases to selected zones canister regeneration. Ceramic trap elements are disclosed adapted for use in a diesel exhaust gas particulate trap formed with a disc-shaped body of open cell ceramic material with opposite faces terminated by partially surrounding peripheral walls which define inlet and outlet gaps at the respective sides of the element. A membrane layer having a pore size substantially smaller than that of the remainder of the body is formed at the outlet surface of the trap element.