An exhaust gas treatment apparatus is provided for use together with a diesel engine in an indoor environment, where the diesel engine is part of, e.g., a vehicle or other machinery. A method of controlling such an exhaust gas treatment apparatus is also provided.

A controller alternately repeats a desorption process of desorbing sulfur compound deposited on an NSR catalyst by supplying fuel from a direct injection valve to exhaust gas, and a pausing process of pausing fuel supply from the injection valve to the exhaust gas. The controller executes a cooling fuel addition for adding engine fuel from the addition valve of the exhaust passage to cool the addition valve during execution of the pausing process, and prohibit the cooling fuel addition during execution of the desorption process. The controller calculates a target temperature of the addition valve at the time of start of the desorption process such that the temperature of the addition valve during execution of the desorption process does not exceed an allowable upper limit temperature and calculates the addition amount at the time of cooling fuel addition.

In a deterioration diagnosis apparatus for a selective catalytic reduction (SCR) catalyst in which when an air fuel ratio of a mixture to be combusted in an internal combustion engine is a lean air fuel ratio, inducement processing is executed which is to induce a water gas shift reaction in a pre-stage catalyst, by changing the air fuel ratio of the mixture from the lean air fuel ratio to a predetermined rich air fuel ratio, and diagnosis processing is executed which is to diagnose deterioration of the SCR catalyst based on an output difference between two air fuel ratio sensors at the time of the execution of the inducement processing, when the SCR catalyst is in a state of being subjected to sulfur poisoning resulting from the execution of the S purge processing of the pre-stage catalyst, diagnosis processing is not executed.

An apparatus for purifying an exhaust gas includes an engine, an exhaust pipe, a first lean NOx trap (LNT) adapted to absorb nitrogen oxide (NOx) contained in the exhaust gas, to release the absorbed NOx, and to reduce the NOx contained in the exhaust gas or the released NOx or to generate ammonia (NH.sub.3), a second LNT adapted to absorb the NOx, to release the absorbed NOx, and to reduce the NOx contained in the exhaust gas or the released NOx or to generate the NH.sub.3, and a selective catalytic reduction (SCR) catalyst adapted to temporarily absorb the NH.sub.3 and to reduce the NOx contained in the exhaust gas, wherein the second LNT is positioned such that an average temperature of the second LNT is lower than that of the first LNT by 50-150 C. based on an average temperature of the exhaust gas.

An exhaust purification system for an internal combustion engine provided with an SO.sub.X storing and releasing catalyst and a particulate filter arranged downstream of the SO.sub.X storing and releasing catalyst. SO.sub.X release processing is performed for releasing SO.sub.X stored in the SO.sub.X storing and releasing catalyst. The SO.sub.X released by the SO.sub.X release processing is supplied to the particulate filter. The larger a time integral showing a sum of products of a temperature of the particulate filter and a time during which it is maintained at that temperature from when SO.sub.X release processing was performed, or the greater the number of times the filter regeneration processing is performed, the greater the concentration of SO.sub.X released by the SO.sub.X release processing.

The present invention relates to an apparatus for reducing greenhouse gas emission in a vessel, and a vessel including the same, which are capable of satisfying IMO greenhouse gas emission regulations by separating and discharging NO.sub.X, SO.sub.X, and CO.sub.2 from exhaust gas exhausted from a vessel engine and increasing CO.sub.2 solubility and CO.sub.2 removal efficiency by removing CO.sub.2 after removing SO.sub.X.

An improved instrument for counting nanoparticles suspended in a gas, particularly in a combustion gas, incorporates a counter device such as a Condensation Particle Counter, incorporates a pre-treatment stage to remove substances which can cause nucleation and false results, comprising a flow through monolith carrying an oxidation catalyst and an absorber, wherein the monolith has a call density of no more than 400 cells per square inch and an open area of at least 80%.

A cleaning system for reducing SOx and particulate matter in exhaust gases from a marine combustion engine, burner or boiler. The cleaning system comprises first and second scrubber process loops having first and second scrubber, respectively, and first and second water circulation tanks, respectively. Water from the first tank is evaporated to water vapor inside the first scrubber by contact with the exhaust gases, whereby the water vapor and the exhaust gases form humid exhaust gases. The humid exhaust gases are transferred to the second scrubber, wherein water from the second tank condensates the water vapor in the humid exhaust gases. A reflux of water from the second scrubber process loop to the first scrubber process loop is provided. At least 60% and more preferred at least 90% of a total amount of alkaline agent supplied to the cleaning system is supplied to the second scrubber process loop.

A pollutant reduction device and method are provided. The pollutant reduction device comprises: an exhaust gas pipe for discharging exhaust gas of a combustion engine; a cleaning water supply pipe for supplying cleaning water; a scrubber for spraying the cleaning water, which is supplied through the cleaning water supply pipe, at the exhaust gas flowing in through the exhaust gas pipe; and a cleaning water discharge pipe for discharging the cleaning water inside the scrubber and supplying the same to a ballast water tank.

An exhaust gas aftertreatment system for a vehicle operated by a combustion engine, in particular for a watercraft, includes a turbine of an exhaust turbocharger in an exhaust line, and at least one storage device, by which at least some of the sulphur pollutants contained in the exhaust gas can be stored and/or put into intermediate storage, at least for a defined period of time. According to the invention, particularly for storing the sulphur pollutants in the high-pressure region, the at least one storage device is arranged in the exhaust line upstream of the at least one turbine in a high pressure region of the exhaust line.