Abstract:
PURPOSE: An exhaust gas purification device is provided to completely oxidize HC and CO included in the exhaust gas by mounting a DOC unit between a CPF unit and a SCR unit. CONSTITUTION: An exhaust gas purification device comprises a smoke reducing unit(30), a diesel oxidation catalyst(40), a blow nozzle(50) and an optional catalytic reduction unit(60). The smoke reducing unit oxidizes hydrocarbon and carbon monoxide included in the exhaust gas using a first diesel oxidation catalyst. The smoke reducing unit collects and reproduces the particulates. The diesel oxidation catalyst is installed in the backend of a CPF unit and oxidizes HC and CO using a second DOC. The diesel oxidation catalyst oxidizes the nitrogen oxide to nitrogen dioxide using second DOC. The blow nozzle is established at the DOC unit backend and spays the reducing agent on the exhaust gas from the DOC unit. The optional catalytic reduction unit is installed the backend of the blow nozzle and restores the nitric oxide within the exhaust to the nitrogen gas.
Abstract:
PURPOSE: A DPF(Diesel Particulate Filter) for a vehicle is provided to equalize the inlet velocity distribution of the exhaust gas of an engine by positioning a unit cell with large cell density and small porosity in the center and a unit cell with small cell density and large porosity toward the radial direction in order. CONSTITUTION: In a DPF(10) for a vehicle having a plurality of lattice-shaped cell structures, the cell density of the cell structure divided in the DPF gradually gets smaller from the center to the radial direction and the porosity gets larger gradually. The cell density and porosity of an A area of one cell structure formed in the center of the DPF is 300 and 52%, respectively. The cell density and porosity of a B area of the cell structure composed of at least unit cells(11) is 200 and 52%, respectively. The cell density and porosity of a C area of the cell structure formed in the radial direction of the B area is 100 and 60%, respectively.
Abstract:
본 발명은 GPF내부의 온도 조건을 이용하여 GPF가 손상되지 않도록 CDA적용 기통수를 결정토록 하는 CDA 적용 차량의 GPF 손상 방지방법에 관한 것이다. 본 발명에 따른 CDA 적용 차량의 GPF 손상 방지방법은, GPF(30, Gasoline Particulate Filter)의 차압을 주기적으로 측정하고 측정된 GPF(30)의 차압에 따라 GPF(30) 내부의 수트(soot) 퇴적량을 산출하는 GPF차압 모니터링단계(S110)와, 상기 GPF차압 모니터링단계(S110)에서 측정된 GPF(30)의 차압을 GPF(30)를 재생하도록 미리 설정된 재생필요차압과 비교하는 차압비교단계(S120)와, 상기 차압비교단계(S120)에서 GPF내의 차압이 재생필요차압보다 높으면, GPF차압에 따른 수트 퇴적량과 CDA운전에 따른 각 CDA모드별 배기가스의 평균 산소농도에 의해, 각 CDA(Cylinder De-activation)모드에 따른 GPF내의 온도를 산출하는 GPF 온도 산출단계(S130)와, 산출된 GPF온도를 이용하여 상기 GPF가 파손되지 않은 온도 이내에서 CDA적용 실린더수를 결정하는 CDA 모드 설정단계(S140)를 포함한다.
Abstract:
PURPOSE: A desulfurization method of a nitrogen oxide absorbing catalyst system is provided to simplify the regeneration logic of desulfurization by deciding the desulfurization time based on the number of success in the regeneration of DPF(Diesel Particulate Filter), since all the trace sulfur compounds included in the exhaust gas ejected when the ultra low sulfur diesel oil is used become poison to an LNT(Lean NOx Trap) catalyst. CONSTITUTION: A desulfurization method of a nitrogen oxide absorbing catalyst system comprises the following steps: determining(S110) whether the number of the success of DPF regeneration reaches the predetermined number of the success of DPF regeneration or not; performing(S120) desulfurization by terminating the DPF regeneration when the number of success of the DPF regeneration reaches the predetermined number of success of the DPF regeneration; entering the desulfurization mode; terminating(S160) the desulfurization after performing the desulfurization for the predetermined time; calculating and calibrating(S170) the amount of the collected PM-10(fine dust) in the DPF generated during the time of desulfurization after the termination of the desulfurization; determining the time for the following DPF regeneration; and comparing the temperature(T) of the inside of the nitrogen oxide absorbing catalyst with the deterioration temperature(X) of the nitrogen oxide absorbing catalyst during the time of the desulfurization. [Reference numerals] (S100) Normal NO_X purification operation mode; (S110) Reaching a predetermined number of success of DPF regeneration?; (S120) Immediately entering a desulfurization mode after terminating the DPF regeneration; (S130) Maintaining a lambda(λ) value below a predetermined value; (S140) LNT catalyst inside temperature(T) > Deterioration temperature(X) ?; (S150) Desulfurization for a predetermined time?; (S160) Terminating the desulfurization; (S170) Calculating and correcting the amount of PM collected in a DPF caused by PM produced during the desulfurization; (S180) Switching the mode to a normal lean operation for preventing overheating of catalyst; (S190) LNT catalyst inside temperature(T) ≤ Predetermined temperature(Y)
Abstract:
PURPOSE: A device and method for purifying secondary injection exhaust gas from vehicle is provided to improve the purifying efficiency of exhaust gas following with the dynamic operation of an engine. CONSTITUTION: A device and method for purifying secondary injection exhaust gas from vehicle comprises a harmful material purification catalyst(10), a secondary injection system, and a controller(40). The harmful material purification catalyst is installed in the fixed position of an exhaust pipe(6) connected to an engine(2). The secondary injection system supplies reducing agent or fuel to catalyst. The controller determines an operation section according to engine RPM and fuel ejection amount under a secondary spray condition. The controller determines a secondary fuel injection pattern by applying a secondary ejection map based on the operation section. The controller purifies NOx and particulate matters by supplying fuel or reducing agent to catalyst using the secondary injection system.
Abstract:
An apparatus and a method for controlling a smoke catalyst filtering unit for a vehicle are provided to prevent the catalyst filtering unit from being blocked by the smoke generated in a failure of an engine. An apparatus for controlling a smoke catalyst filtering unit for a vehicle includes a catalyst filtering unit(16), a bypass pipe, a bypass valve(22), and a control unit. The catalyst filtering unit is connected to a diesel engine and is installed in an exhaust gas pipe through which exhaust gas is discharged to purify smoke. The bypass pipe is branched out from the front end of the catalyst filtering unit so that the exhaust gas can be bypassed without passing through the catalyst filtering unit. The bypass valve opens and closes the bypass pipe. If the smoke is excessively discharged due to a problem of the diesel engine, the bypass valve is opened to bypass the smoke and the operation of an EGR(Exhaust Gas Recirculation) system is stopped by the control unit.
Abstract:
A method and an apparatus for controlling regeneration of a simultaneous NOx-PM reduction apparatus, comprising a lean NOx trap and a catalytic particulate filter are provided to improve regeneration efficiency by performing regeneration under the two-step exhaust gas temperature condition including a mild regeneration step where the inner temperature of the catalytic particulate filter is equal to or lower than 700 Deg.C and a strong regeneration step where the inner temperature of the catalytic particulate filter is equal to or higher than 800 Deg.C. An apparatus comprises a first exhaust gas temperature sensor(120) for detecting the temperature of exhaust gas of an engine(160); a second exhaust gas temperature sensor(125) for detecting the temperature of exhaust gas flowing between a lean NOx trap and a catalytic particulate filter in a simultaneous NOx-PM reduction apparatus(100); a catalytic particulate filter temperature sensor(130); a differential pressure sensor(135) for measuring the pressure drop of the simultaneous NOx-PM reduction apparatus; an oxygen sensor(140) for detecting the oxygen density of the exhaust gas of the engine; a NOx sensor(145) for detecting the NOx density of the exhaust gas; and a control unit for controlling regeneration of the simultaneous NOx-PM reduction apparatus on the basis of the signals received from the sensors.
Abstract:
본 발명은 질소산화물 및 입자상 물질 동시 저감 시스템에 관한 것으로서, 전방으로 CPF가 설치되고, 그 후방에는 NOx 흡장촉매와 DOC가 직렬 설치되며, 상기 CPF 전방의 배기 파이프에서 분기되어 NOx 흡장촉매의 전방에 출구를 가지는 배기가스 배관이 설치되되, 이 배기가스 배관에는 DFC와 이 DFC 전단으로 디젤 연료를 분사하는 2차 분사노즐이 설치되는 한편, 상기 DFC 전방의 배기가스 배관상에 위치되는 배기가스 분배밸브와 상기 DOC 후방(NOx 흡장촉매 후방)에 위치되는 NOx 센서가 설치되어, ECU가 NOx 센서의 신호로부터 재생시점을 판단하게 되면 상기 배기가스 분배밸브를 개방함과 아울러 상기 2차 분사노즐을 작동시켜 NOx 흡장촉매의 재생이 이루어지도록 한 질소산화물 및 입자상 물질 동시 저감 시스템에 관한 것이다. 이러한 본 발명에 의하면, CPF와 NOx 흡장촉매의 효율과 연비를 동시에 높일 수 있으며, NOx 흡장촉매의 재생시에 환원제로 작용하는 연료를 NOx 흡장촉매에 직접 분사하던 것에 비해 촉매의 열화가 방지되는 장점이 있게 된다. 또한, 엔진에서의 연료 후분사에 의해 전방의 CPF에서 산화반응이 일어나 온도가 상승하는 바, 탈황 과정에 필요한 온도가 쉽게 달성되는 장점이 있다. 질소산화물, 입자상 물질, NOx 흡장촉매, 연료분해촉매