摘要:
A method (10) for injecting ammonia (NH3) into exhaust gas upstream of a catalyst of an aftertreatment system includes the steps of determining whether a regeneration event is imminent (14) on the basis of predetermined parameters, and determining whether dosing parameters are met (22). The method (10) further includes the steps of calculating an amount of NH3 to fill the catalyst (18) and adjusting a quantity of NH3 dosed (22) before the regeneration event occurs.
摘要:
A method for injecting ammonia into an exhaust gas stream downstream of a diesel engine includes providing an exhaust gas passageway (11) from the diesel engine to an ambient (14). The exhaust gas passageway (11) includes an NOx Slip Catalyst (NSC) 20 downstream of an NOx Particulate Filter (NPF) 18. The method includes emitting exhaust gas (EG) through the exhaust gas passageway (11), and selectively injecting ammonia (NH3) upstream of the NPF 18, upstream of the NSC (20), both upstream of the NPF and the NSC, or not injecting ammonia, depending on the temperature of the exhaust gas at the NPF and at the NSC.
摘要:
A method for injecting ammonia into an exhaust gas stream downstream of a diesel engine includes providing an exhaust gas passageway (11) from the diesel engine to an ambient (14). The exhaust gas passageway (11) includes an NOx Slip Catalyst (NSC) 20 downstream of an NOx Particulate Filter (NPF) 18. The method includes emitting exhaust gas (EG) through the exhaust gas passageway (11), and selectively injecting ammonia (NH3) upstream of the NPF 18, upstream of the NSC (20), both upstream of the NPF and the NSC, or not injecting ammonia, depending on the temperature of the exhaust gas at the NPF and at the NSC.
摘要:
A system and method of effective regeneration of a diesel particulate filter used in the exhaust system of a diesel engine during low engine operating temperatures, is disclosed. Generally speaking, a catalytic burner system and method used in filter regeneration on a diesel engine comprises a burner diesel oxidation catalyst (BDOC) coupled to an exhaust flow of the diesel engine, a mixer fluidly coupled to the BDOC, a diesel oxidation catalyst (DOC) fluidly coupled to the mixer, and a diesel particulate filter (DPF) fluidly coupled to the DOC, wherein the BDOC directs the exhaust flow through the mixer, the DOC and the DPF during a regeneration cycle of the DPF under low engine temperature operating conditions.
摘要:
A process and apparatus for oxidizing components of a feed gas mixture in a heat regenerative reactor are provided. The heat regenerative reactor comprises a vessel having a two ends, the interior of which defines an unfired heat exchange/reaction zone containing a gas-permeable bed comprising heat exchange material in which the components of the feed gas mixture are oxidized. A gas handling system selectively introduces the feed gas mixture into one end of the vessel and discharges reacted gas through the other end of the vessel such that the direction of gas flow through the vessel may be reversed. At the time of flow reversal, a bypass system introduces the feed gas mixture into the vessel at a point intermediate the two ends of the vessel so that the feed gas mixture bypasses a portion of the gas-permeable bed. During bypass, a purging system purges unreacted feed gas mixture from the heat exchange/reaction zone. The process and apparatus described herein provides for continuous processing of the feed gas mixture while avoiding the discharge of unreacted feed gas at the time of flow reversal.