摘要:
A method of operating a syngas generator within a desired temperature range, despite a need for intermittent syngas output, involves switching between operating the syngas generator in a rich mode and a lean mode. Operation of the syngas generator in both the rich mode and the lean mode sustains the operating temperature of the syngas generator within that desired temperature range, particularly for non-catalytic reactors. The method of switching from the lean mode to the rich mode of operation can include decreasing the oxygen-to-carbon ratio of reactants supplied to the syngas generator. The flow rate of one or more of the reactant streams supplied to the syngas generator can be actively controlled in order to switch operation of the syngas generator between the rich and lean modes.
摘要:
Vorrichtung zur Verminderung der Emission von polychlorierten Dibenzo-Dioxinen und polychlorierten Dibenzo-Furanen die an mindestens einem übergangsmetallhaltigen Katalysator entstanden sind, wobei der übergangsmetallhaltige Katalysator auf einem Partikelfilter, der in der Abgasableitung einer Brennkraftmaschine verbaut ist, angebracht ist und von diesem nicht zerstörungsfrei getrennt werden kann. Zur Verminderung der Emission ist zwischen dem übergangsmetallhaltigen Katalysator und dem Abgas auf der Reingasseite mindestens ein Molekularsieb, das polychlorierte Dibenzo-Dioxine und polychlorierte Dibenzo-Furane zurückhält, angeordnet. Weiter ist vorgesehen, dass die Anströmseite des Molekularsiebes und/ oder die Vorrichtung stromauf zum Molekularsieb eine Oxidationsaktivität für Kohlenwasserstoffe, polychlorierten Dibenzo-Dioxinen und polychlorierten Dibenzo-Furanen aufweist.
摘要:
An NOX occluding and reducing catalyst 7 is arranged in an exhaust gas passage 2 of an engine 1 so as to occlude, reduce and purify NOX contained in an exhaust gas. An H2 sensor 33 is arranged in the exhaust gas passage on a downstream side of the NOX occluding and reducing catalyst 7 and a hydrogen component concentration of the exhaust gas is detected. When an amount of NOX occluded in the NOX occluding and reducing catalyst is increased to a predetermined value, an electronic control unit (ECU) 30 of the engine operates the engine at a rich air-fuel ratio, and a regenerating operation, by which a rich air-fuel ratio exhaust gas is supplied to the NOX occluding and reducing catalyst, is executed so as to reduce and purify NOX which is occluded in the NOX occluding and reducing catalyst. At the time of executing the regenerating operation, when the H2 sensor 33 detects hydrogen components in the exhaust gas, ECU 30 finishes the regenerating operation. Due to the foregoing, it is possible to accurately judge the time for terminating the regenerating operation of the NOX occluding and reducing catalyst.
摘要翻译:在发动机1的排气通路2中配置有NOX吸留还原催化剂7,以吸留,还原净化废气中含有的NOX。 H 2传感器33布置在NO X吸留还原催化剂7的下游侧的排气通道中,并且检测排气的氢成分浓度。 当在NOx吸留还原催化剂中吸留的NOX量增加到预定值时,发动机的电子控制单元(ECU)30以浓空燃比操作发动机,并且执行再生操作,通过该再生操作, 向NOx吸留还原催化剂供给浓空燃比排气,以便还原和净化吸留在NOx吸留还原催化剂中的NOx。 在执行再生操作时,当H2传感器33检测到排气中的氢成分时,ECU30结束再生操作。 由此,能够准确地判断NOX吸留还原催化剂的再生动作结束时刻。
摘要:
An exhaust aftertreatment system comprising two or more branches, at least one of which contains a NOx adsorber-catalyst. The branches unite downstream into a trailing conduit that contains an ammonia-SCR catalyst. Ammonia generated by the NOx adsorber-catalyst during regeneration is stored for later use by the SCR catalyst. One advantage of this configuration is a continuous or near continuous presence of oxygen within the trailing exhaust conduit. The continuous presence of improves the efficiency of the SCR catalyst. Another concept is to configure a multi-branch exhaust aftertreatment system without valves, dampers, or other electronically controlled devices adapted to selectively alter the distribution of the exhaust between the branches. The absence of such devices generally results in a comparatively balanced division of exhaust between the branches. One benefit of this configuration is improved reliability as compared to systems that use valves.
摘要:
An exhaust gas purifying apparatus for an internal combustion engine having an exhaust system. The apparatus includes a NOx purifying device provided in the exhaust system. This device removes NOx from exhaust gases when a concentration of oxygen in the exhaust gases is higher than a concentration of reducing components in the exhaust gases; generates ammonia and retains the generated ammonia when the concentration of reducing components in the inflowing exhaust gases is higher than the concentration of oxygen; and purifies NOx with the retained ammonia when the concentration of reducing components in the inflowing exhaust gases is lower than the concentration of oxygen. A residual amount of ammonia retained in the NOx purifying device is estimated. The concentration of reducing components in the exhaust gases is switched with respect to the concentration of oxygen according to the estimated residual amount.
摘要:
Es wird eine Abgasreinigungsanlage zur Reinigung des Abgases einer vorzugsweise mager betriebenen Brennkraftmaschine, insbesondere eines in Kraftfahrzeugen verwendeten Dieselmotors vorgeschlagen, in der ein SCR-Katalysator angeordnet ist und mit einer Reduktionsmittelversorgung, wobei von der Reduktionsmittelversorgung Ammoniak eingangsseitig des SCR-Katalysators in das Abgas der Brennkraftmaschine zugebbar ist, wobei die Reduktionsmittelversorgung eine Ammoniak-Erzeugungseinheit zur Erzeugung des in das Abgas der Brennkraftmaschine (1) zugebbaren Ammoniaks aufweist. Erfindungsgemäß ist die Ammoniak-Erzeugungseinheit zur Umsetzung von mit Luft oder sauerstoffhaltigem Abgas zugeführtem Stickstoff zu Ammoniak ausgebildet.
摘要:
A very high efficiency NO x aftertreatment system for use in lean burn engines is disclosed. A lean NO x adsorber is fluidly connected to a selective catalytic reduction catalyst to use the ammonia formed within the NO x adsorber, during regeneration of the NO x adsorber while periodically operating the engine in a fuel-rich combustion mode, to reduce NO x remaining in the exhaust gas stream after passage through the NO x adsorber during normal operation of the engine in a lean burn combustion mode.
摘要:
An exhaust system for an internal combustion engine, the exhaust system comprising, a lean NOx trap, a NOx storage and reduction zone on a wall flow monolithic substrate having a pre-coated porosity of 50% or greater, the NOx storage and reduction zone comprising a platinum group metal loaded on one or more first support, the or each first support comprising one or more alkaline earth metal compound, and a selective catalytic reduction zone on a monolithic substrate, the selective catalytic reduction zone comprising copper or iron loaded on a second support, the second support comprising a molecular sieve.