An aftertreatment system for reducing constituents of an exhaust gas having a sulfur content includes: an oxidation catalyst; a filter disposed downstream of the oxidation catalyst; and a controller configured to, in response to determining that the filter is to be regenerated and a desulfation condition being satisfied: cause a temperature of the oxidation catalyst to increase to a first regeneration temperature that is greater than or equal to 400 degrees Celsius and less than 550 degrees Celsius, cause the temperature of the oxidation catalyst to be maintained at the first regeneration temperature for a first time period, and after the first time period, cause the temperature of the oxidation catalyst to increase to a second regeneration temperature equal to or greater than 550 degrees Celsius.

A method and installation for removing a gas from a flow of a gas mixture. A first liquid (82) is introduced in the flow (106) for evaporative cooling and saturation of the gas mixture. Small droplets of a second liquid (84) are provided which are capable of adsorbing and dissolving said gas and of a size small enough not to be sedimented by gravitation and big enough to be centrifugally separated. The small droplets are sprayed into the flow for adsorbing and dissolving said gas into the droplets, and the small droplets are centrifugally separated from the flow.

An exhaust catalyst management apparatus to be applied to a vehicle includes a differential pressure sensor and one or more processors. The differential pressure sensor detects an accumulation state of an exhaust-containing substance in a catalyst device. The one or more processors are coupled to the differential pressure sensor and a vehicle outside sensor. The one or more processors determine whether or not travel environment is suited to carrying out an output control for removal, based on a result of the detection of surroundings of the vehicle by a vehicle outside sensor. Upon determining that the travel environment is suited to carrying out the output control for removal, the one or more processors carry out the output control for removal, while the vehicle is traveling, in accordance with a result of the determination of the accumulation state of the exhaust-containing substance in the catalyst device.

A method and modular desulfurization-decarbonization apparatus for removing contaminants from exhaust gas is described. The apparatus comprises discrete modular units with distinct functions. The modular units may be housed in standard shipping containers and installed on cargo ships. The modules can be removed and replaced while docking with minimal disruption to ship and port operations.

A gas purification apparatus includes: a housing to which a gas is introduced; a filter portion for removing an impure substance in the gas from the gas, the filter portion being disposed inside the housing; and a gas purification agent for removing a removal target substance in the gas from the gas, the gas purification agent being disposed, inside the housing, on the filter portion or in a space at a downstream side of the filter portion with respect to a flow of the gas.

A method and modular desulfurization-decarbonization apparatus for removing contaminants from exhaust gas is described. The apparatus comprises discrete modular units with distinct functions. The modular units may be housed in standard shipping containers and installed on cargo ships. The modules can be removed and replaced while docking with minimal disruption to ship and port operations.

The present invention is applied to an exhaust system provided with a three-way catalyst and a NOx catalyst which are provided in an exhaust passage of an engine and to which sulfur components in exhaust adhere and release the attached sulfur components by rich components in exhaust, and NOx sensors provided downstream of the catalysts. The NOx sensor is a limiting current type sensor. It is determined whether a sulfur release state is present in which a sulfur component is released from the three-way catalyst and the NOx catalyst. When it is determined that it is in the state of sulfur release, reaction suppression processing for suppressing the reaction between oxygen and sulfur components in the pump cell electrodes and the monitor cell electrodes of the NOx sensors is performed.

An exhaust gas cleaning system comprises a first sub system including a scrubber unit comprising a scrubber arranged to wash the exhaust gas with a scrubber fluid, and a centrifugal separator arranged in communication with the scrubber unit for receiving the scrubber fluid after washing and separate it into a first and a second fraction, which second fraction is more polluted than the first fraction. The exhaust gas cleaning system further comprises a second sub system including a membrane filter arranged in communication with the centrifugal separator for receiving the first fraction output from the centrifugal separator and separating it into a third and a fourth fraction, which fourth fraction is more polluted than the third fraction. A method for cleaning exhaust gas onboard a ship involves cleaning an exhaust gas onboard a ship.

Methods and installations for treatment of exhaust gases from marine diesel engines, in particular for reduction of the sulphur oxides (SO.sub.x) in such gases, where the reaction products resulting from the mixing of an alkaline aerosol with the exhaust gases are separated-out by means of one or more rotating centrifugal separator rotors (20) of the kind comprising a stack of narrowly spaced separation discs (22).

A gas purification apparatus includes: a housing to which a gas is introduced; a filter portion for removing an impure substance in the gas from the gas, the filter portion being disposed inside the housing; and a gas purification agent for removing a removal target substance in the gas from the gas, the gas purification agent being disposed, inside the housing, on the filter potion or in a space at a downstream side of the filter portion with respect to a flow of the gas.