Patent ID: 8176732
Filing Date: 2012-05-15
Classification: F01N,Y02T

Abstract:
1. An apparatus for treating engine exhaust gas, comprising: an exhaust conduit for leading exhaust gases from an engine to an exhaust outlet; a particulate filter connected in the exhaust conduit to receive exhaust gas; a heat source connected in the exhaust conduit upstream of the particulate filter; a heat exchanger connected to receive exhaust gas exiting the particulate filter, the heat exchanger comprising a housing having a first inlet to receive exhaust gas from the engine and a first outlet connected to the exhaust conduit upstream of the heat source, and having second inlet to receive exhaust gas exiting the particulate filter and a second outlet connected to the exhaust conduit leading to the exhaust outlet, the heat exchanger configured to put the exhaust gas entering the second inlet in heat transfer contact with gas entering the first conduit, the heat exchanger being disposed upstream of and spaced from the heat source and particulate filter; and, a bypass conduit connected in the exhaust conduit upstream of the first inlet of the heat exchanger and downstream of the first outlet of the heat exchanger, the bypass conduit having a valve controlled for selectively directing exhaust gas into the heat exchanger or to the exhaust conduit downstream of the first outlet, bypassing the heat exchanger.