ELECTRONIC CONTROLLED ENGINE EXHAUST TREATMENT SYSTEM TO REDUCE NOX EMISSIONS

摘要

A system and method is provided for treating engine exhaust gases produced b y an internal comubistion engine (12). The internal combustion engine (12) has an exhaust gas recirculation circuit that diverts engine exhaust gas from an engine exhaust gas manifold (58) to an engine air intake manifold (69). An exhaust gas recirculation valve (66) is further provided for controlling the amount of engine exhaust gas diverted toward the engine air intake manifold (69). Additionally, a small meter pump (67) is provided to create a pressure differential sufficient to introduce a finely tunable and controllable amoun t of engine exhaust gas into the engine air intake manifold (69).