FILTRATION SYSTEM FOR DIESEL ENGINE EXHAUST - II

摘要

A filtration system operative to remove oxidizable particulates from the exhaust gas of a diesel engine is disclosed. The system has a filter element to trap and collect particulates in the exhaust gas, ignition means supplied with energy for a period only sufficient to ignite a leading portion of the particulate collection, and means for conducting a flow of gas with excess oxygen thorugh the filtration means immediately following ignition without addition of other energy, the flow of gas with excess oxygen being utilized to support the continued oxidation of the ignited particulate collection. The ignition means may comprise (a) apparatus for adding excess hydrocarbon fuel either to (i) the gas flow through the intake manifold of the engine, (ii) the exhaust gas exiting from the engine, or (iii) a separate supply of compressed air, and (b) a supplementary heated catalyst located between the exhaust manifold of the engine and the filter element for acting upon the hydrocarbon rich gas flow, the catalyst being effective to bring about ignition of the hydrocarbon rich gas and produce a heated exhaust gas high enough in temperature to ignite at least a portion of the particulates in the filter element.