Abstract:
A method is provided for predicting NOx loading at a DeNOx catalyst by which a NOx amount actually stored in the DeNOx catalyst can be precisely predicted and to an exhaust system which controls a regeneration timing of the DeNOx catalyst and amount of a reducing agent which is injected by using the method. The method may include calculating mass flow of NOx stored at the DeNOx catalyst, calculating mass flow of NOx thermally released from the DeNOx catalyst, calculating mass flow of NOx chemically released from the DeNOx catalyst, and calculating NOx amount actually stored at the DeNOx catalyst by using the mass flow of NOx stored at the DeNOx catalyst, the mass flow of NOx thermally released from the DeNOx catalyst, and the mass flow of NOx chemically released from the DeNOx catalyst.
Abstract:
A system for purifying an exhaust gas and an exhaust system having the same while preventing degradation of a selective reduction catalyst may include an exhaust pipe connected to an engine, the exhaust gas generated at the engine passing through the exhaust pipe, a particulate filter mounted on the exhaust pipe, coated with a selective reduction catalyst adapted to reduce nitrogen oxides contained in the exhaust gas by an injection of a reducing agent, and adapted to trap particulate matters contained in the exhaust gas, and one or more injectors adapted to inject the reducing agent and/or oxygen storage capacity material together or separately into the exhaust gas passing through the exhaust pipe.
Abstract:
A catalyst for NOx storage and reduction may include a carrier that contains alkali metal and Al, or alkali earth metal and Al, a NOx storage element of alkali metal, alkali earth metal or rare earth element, and one or more noble metals that are selected from the group consisting of Pt, Pd, Ru, Ag, Au and Rh. The catalyst for NOx storage and reduction shows excellent NOx storage and reduction capability, maintains excellent storage and reduction capability especially before and after deterioration and sulfation, and shows excellent catalytic activity under low temperature environment, while maintaining unusually high hydrophobicity.
Abstract:
An exhaust device for a diesel vehicle may include a diesel fuel catalyst provided downstream of a turbocharger, a hydrocarbon Selective Catalyst Reduction (SCR) catalyst provided downstream of the diesel fuel catalyst, a catalyst-coated diesel particulate filter provided downstream of the hydrocarbon SCR catalyst, and a secondary fuel injector provided on an exhaust gas pipe between the turbocharger and the diesel fuel catalyst.
Abstract:
An exhaust purification system for an internal combustion engine, and a desulfurization method for the same, recovers purification performance of a denitrification catalyst by removing sulfur poisoned at the denitrification catalyst in an exhaust system. The exhaust purification system may include an exhaust pipe through which an exhaust gas flows, the exhaust gas being generated at the internal combustion engine having a first injector injecting a fuel to a combustion chamber, a second injector mounted at the exhaust pipe and additionally injecting the fuel, a particulate filter mounted at the exhaust pipe downstream of the second injector and filtering particulate matters (PM) in the exhaust gas, a denitrification catalyst mounted at the exhaust pipe downstream of the particulate filter and reducing nitrogen oxide contained in the exhaust gas, and a control portion performing desulfurization of the denitrification catalyst when a desulfurization entering condition and a desulfurization condition are satisfied during regenerating the particulate filter.
Abstract:
An exhaust system may include an exhaust line through which exhaust gas that is formed in an engine is exhausted, a nitrogen oxide purification catalyst that is disposed on the exhaust line to reduce nitrogen oxide that is included in the exhaust gas, an injector to additionally inject fuel into the exhaust line or a cylinder, and a fuel cracking catalyst that is disposed between the injector and the nitrogen oxide purification catalyst to crack the fuel that is injected through the injector, to transform the injected fuel into a high efficiency reducing agent, and to raise the temperature of the latter part thereof through an oxidation reaction.
Abstract:
A purification system for variable post injection in LP EGR, the system includes a turbo charger disposed downstream of a diesel engine, a DPF (catalyzed particulate filter) disposed downstream of the turbo charger, a NOx reduction apparatus disposed upstream or downstream of the DPF, a bypass line diverged from the DPF for mixing exhaust gas and air inflowing the turbo charger, a exhaust gas control portion disposed downstream of the DPF for controlling flowing of the exhaust gas and a lean/rich controlling portion for controlling lean/rich of the exhaust gas.
Abstract:
A method for predicting a NOx amount, may include determining a reference NOx amount according to a driving condition of an engine, primarily correcting the reference NOx amount according to an exhaust gas recirculation (EGR) ratio, and secondarily correcting the primarily corrected NOx amount according to an environmental factor and the driving condition.
Abstract:
An apparatus for purifying exhaust gas may include a CPF device primarily oxidizing hydrocarbon and carbon monoxide in the exhaust gas by using a first DOC, and trapping and regenerating particulate material (PM), a DOC device mounted downstream of the CPF device, secondarily oxidizing the HC and the CO in the primarily oxidized exhaust gas by using a second DOC, and oxidizing nitrogen monoxide into nitrogen dioxide by using the second DOC, a nozzle mounted downstream of the DOC device, and dosing a reducing agent to the exhaust gas secondarily oxidized by the DOC device, and a selective catalytic reduction device mounted downstream of the nozzle, and reducing nitrogen oxide in the exhaust gas into nitrogen gas) by using the NO2 generated in the DOC device and the reducing agent.
Abstract:
A catalyst for NOx storage and reduction may include a carrier that contains alkali metal and Al, or alkali earth metal and Al, a NOx storage element of alkali metal, alkali earth metal or rare earth element, and one or more noble metals that are selected from the group consisting of Pt, Pd, Ru, Ag, Au and Rh. The catalyst for NOx storage and reduction shows excellent NOx storage and reduction capability, maintains excellent storage and reduction capability especially before and after deterioration and sulfation, and shows excellent catalytic activity under low temperature environment, while maintaining unusually high hydrophobicity.