Patent attributes
Methods, constructions, and systems for treating engine emissions. An engine includes a crankcase, an air intake, a blow-by vent, and an exhaust port; the crankcase emits blow-by gases through the blow-by vent, and the engine produces an exhaust stream through the exhaust port. The blow-by gases are directed through a blow-by filter to produce filtered gases. The filtered gases are directed back into the air intake of the engine; and the exhaust stream is treated with at least one of a catalytic converter, a flow through filter, and a diesel particulate filter. Total particulate matter (PM) emissions of a turbo-charged diesel engine having an engine crankcase and an exhaust tailpipe are reducible. The total emissions includes particulate matter matter emissions from the engine crankcase added to the particulate matter emissions from the exhaust tailpipe. The method includes filtering blow-by gases and directing filtered blow-by gases back into the engine; and treating the exhaust stream with a catalyst; whereby the total emissions are reduced by greater than 25% when compared to the same engine that does not filter blow-by gases nor treat the exhaust stream. Usable systems include: a blow-by filter in gas-flow communication with a blow-by vent of an engine crankcase; a diesel oxidation catalyst arrangement in gas-flow communication with an exhaust port of an engine crankcase, a diesel particulate filter (active or passive), a flow through filter, and combinations thereof.