The present invention relates to use of a lubrication oil that forms water-soluble ash when combusted in an engine system, where the engine system comprises an internal combustion engine; an exhaust gas system comprising a diesel particulate filter to capture particulate matter from the exhaust gases, including the water-soluble ash; and an exhaust gas conduit to lead exhaust gases from the internal combustion engine to the exhaust gas system, and to collect condensed water formed by a cold start and/or a cold operation of the internal combustion engine and lead the condensed water through the diesel particulate filter, thereby dissolving and removing the water-soluble ash from the diesel particulate filter.

An engine system comprising an internal combustion engine operated by a fuel and lubricated by a lubrication oil comprising at least one additive that renders ash formed by combustion of the lubrication oil ammonia-soluble ash; an exhaust gas system for cleaning an exhaust gas flow from the internal combustion engine , the exhaust gas system comprising a diesel particulate filter to capture particulate matter from the exhaust gases, wherein the particulate matter comprises the ammonia-soluble ash; an exhaust gas conduit to lead exhaust gases from the internal combustion engine through the exhaust gas system; and an injection device to add a solvent comprising ammonia or an ammonia-forming compound into the exhaust gas flow upstream of the diesel particulate filter, wherein the exhaust gas conduit collects the solvent and lead the solvent through the diesel particulate filter, thereby dissolving and thus removing the ammonia-soluble ash from the diesel particulate filter.

Method and system for removal of particles such as soot, ash and heavy metals, and optionally additionally NO.sub.X and SO.sub.X being present in exhaust gas from an engine or process equipment.

A particulate filter for trapping the particulate matter which is contained in the exhaust gas is provided inside an engine exhaust passage. Additional fuel is secondarily injected from a fuel injector in an engine expansion stroke or exhaust stroke or hydrocarbons are secondarily added from an addition valve which is provided upstream of the particulate filter in the exhaust pipe. An amount of hydrocarbons which come from the fuel injector or addition valve and then adhere in the form of a liquid to the inflow end of the particulate filter, and an amount of particulate matter which reaches the inflow end of the particulate filter are respectively estimated. A degree of clogging at the inflow end of the particulate filter is estimated based on the amount of hydrocarbons and the amount of particulate matter.

An exhaust gas treating device includes a honeycomb structure including an inner honeycomb structure body, an outer honeycomb structure body disposed at a position which surrounds a part of a circumference of the inner honeycomb structure body and is away from the inner inflow end face of the inner honeycomb structure body, and plugging portions arranged in parts of cells; a can member which stores the honeycomb structure and has an inlet and a second outlet for an exhaust gas; and an opening/closing valve to open and close the second outlet of the can member.

A control device is configured to estimate a soot deposition amount (PM deposition amount) in a DPF for an exhaust purification device that is configured to purify exhaust of a diesel engine using the DPF, and determine a regeneration timing for the diesel engine based on the estimated PM deposition amount. As a technique of determining the regeneration timing, the control device employs a first determination technique of detecting that the PM deposition amount is a first threshold or more and a state in which the PM deposition amount is the first threshold or more has continued for a first predetermined time and a second determination technique of detecting that the PM deposition amount is a second threshold (>the first threshold) or more and a state in which the PM deposition amount is the second threshold or more has continued for a second predetermined time.

A method of operating a particulate matter sensor includes accumulating particulate matter on the sensor, thereby changing resistance between electrodes of the sensor. The sensor provides a signal that varies based upon an amount of the particulate matter on the sensor and includes a measurement cycle that includes a deadband zone in which the resistance is greater than a first predetermined value, followed by an active zone in which the resistance is less than or equal to the first predetermined value, followed by a regeneration zone. A first bias voltage is applied across the electrodes during the deadband zone and a second bias voltage which is less than the first bias voltage is applied across the electrodes during the active zone. An output that is representative of the amount of the particulate matter is calculated after an end of the deadband zone is reached and prior to an end of the measurement cycle.

A particulate filtering apparatus for dry filtering exhaust gases of a diesel engine includes at least two compartments independently arranged in parallel with respect to a flow of the exhaust gases. Each of the compartments is equipped with at least one shut-off valve for regulating the flow of gas passing through the compartment and further includes one or more filters adapted to hold the particulate and an emission device to generate a countercurrent gas pulse flow at the one or more filters. A central control unit operates and controls the at least one shut-off valve and of said emission device. Each of the at least two compartments further includes an injector operably controlled by the central control unit for the inlet of hot gases into the at least two compartments.

A method for execution with an exhaust-gas particle filter which is operated with an exhaust-gas aftertreatment system, wherein the exhaust-gas particle filter has a filter wall along which exhaust gas is conducted for filtering purposes; wherein the method includes a regeneration phase with the steps: a) setting a soot load on the exhaust-gas particle filter, wherein the set soot load effects the formation of a soot layer on ash deposited on the filter wall; and b) subsequently mobilising the deposited ash by burning off the formed soot layer during the course of an active regeneration of the exhaust-gas particle filter.

An estimated trapped amount (PM) that is an estimated value of an amount of particulate matter that is trapped in a particulate filter arranged in an engine exhaust passage is calculated based on an engine operating state, and PM removal control is performed when the estimated trapped amount exceeds an upper limit amount. Reference temperature increase control is performed to remove the particulate matter from the particulate filter, and an actual temperature that is the temperature of the particulate filter while the reference temperature increase control is being performed is detected. A reference temperature that is the temperature of the particulate filter when it is assumed that the reference temperature increase control has been performed when the amount of particulate matter trapped in the particulate filter is a reference initial trapped amount is stored in advance. The estimated trapped amount is corrected based on the actual temperature and the reference temperature.