Abstract: Directing exhaust gas around a catalyst may pre-heat the catalyst and may thereby bring the catalyst quickly in its operating temperature range. An exhaust gas treatment system for treating the exhaust gas may include a first flow path, a second flow path, and a control system. The first flow path may include a catalyst. The second flow path may be coaxially arranged in heat exchange relation with respect to the first flow path. The control system may be configured to control the flow of exhaust gas through the first flow path or the second flow path dependent upon the catalyst temperature.

Abstract: For exhaust gas recirculation in internal combustion engines operating, for example, with low sulphur marine diesel oil, an exhaust gas cooler with a cooling unit may be applied that uses a liquid injection system to maintain clean and/or clean a cooling surface of the cooling unit. The liquid injection system may provide liquid into an exhaust gas passage upstream of and or along a condensation starting region the cooling surface, thereby reducing the formation of films and deposits from particulate matter and condensing liquid of an evaporated liquid within the exhaust gas such as sulphuric acid and/or water, as those deposits could otherwise at least partially block the exhaust gas cooler.

Abstract: Directing exhaust gas around a catalyst may pre-heat the catalyst and may thereby bring the catalyst quickly in its operating temperature range. An exhaust gas treatment system for treating the exhaust gas may include a first flow path, a second flow path, and a control system. The first flow path may include a catalyst. The second flow path may be coaxially arranged in heat exchange relation with respect to the first flow path. The control system may be configured to control the flow of exhaust gas through the first flow path or the second flow path dependent upon the catalyst temperature.

Abstract: For exhaust gas recirculation in internal combustion engines operating, for example, with low sulphur marine diesel oil, an exhaust gas cooler with a cooling unit may be applied that uses a liquid injection system to maintain clean and/or clean a cooling surface of the cooling unit. The liquid injection system may provide liquid into an exhaust gas passage upstream of and or along a condensation starting region the cooling surface, thereby reducing the formation of films and deposits from particulate matter and condensing liquid of an evaporated liquid within the exhaust gas such as sulphuric acid and/or water, as those deposits could otherwise at least partially block the exhaust gas cooler.