Low temperature emission system having turbocharger bypass

摘要

An exhaust system for an engine is disclosed. The exhaust system may have a NOx reducer located to receive exhaust from the engine, and a bypass circuit configured to selectively pass supercharged air to the NOx reducer. The exhaust system may also have a valve disposed within the bypass circuit to regulate the flow of supercharged air, and a controller in communication with the valve. The controller may be configured to move the valve to pass the supercharged air and cool the exhaust received by the NOx reducer. The controller may also be configured to move the valve to reduce the passing of the supercharged air and remove sulfur compounds from the NOx reducer.