Abstract: A reagent dosing system for dosing a reagent into the exhaust gas stream of an internal combustion engine includes a reagent tank for storing a supply of reagent; an injector module including an atomizing dispenser and a positive-displacement metering pump which draws reagent from the reagent tank and delivers it to the dispenser; a supply line coupling the reagent tank to the injector module; a dosing control unit operable to control the injector module to inject reagent into the exhaust gas stream; and an additional priming pump arranged, in use, to urge reagent along the supply line toward the injector module under selected conditions.

Abstract: A reagent dosing system for dosing a reagent into the exhaust gas stream of an internal combustion engine includes a reagent tank for storing a supply of reagent; an injector module including an atomising dispenser and a positive-displacement metering pump which draws reagent from the reagent tank and delivers it to the dispenser; a supply line coupling the reagent tank to the injector module; a dosing control unit operable to control the injector module to inject reagent into the exhaust gas stream; and an additional priming pump arranged, in use, to urge reagent along the supply line toward the injector module under selected conditions.

Abstract: A method of dosing a reagent into an exhaust gas stream of an internal combustion engine having an SCR catalyst, the method comprising injecting reagent from a reagent tank into the exhaust gas stream at a position upstream of the SCR catalyst using a reagent injector in accordance with a first dosing schedule in order to remediate a predetermined proportion of NOx in the exhaust gas stream, the first dosing schedule being associated with a first range of engine operating conditions; and injecting reagent from the reagent tank into the exhaust gas stream at a position upstream of the SCR catalyst using a reagent injector in accordance with a second dosing schedule in order to enable heat transfer between the reagent injector and said injected reagent, the second dosing schedule being associated with a second range of engine operating conditions.

Abstract: A method of dosing a reagent into an exhaust gas stream of an internal combustion engine having an SCR catalyst, the method comprising injecting reagent from a reagent tank into the exhaust gas stream at a position upstream of the SCR catalyst using a reagent injector in accordance with a first dosing schedule in order to remediate a predetermined proportion of NOx in the exhaust gas stream, the first dosing schedule being associated with a first range of engine operating conditions; and injecting reagent from the reagent tank into the exhaust gas stream at a position upstream of the SCR catalyst using a reagent injector in accordance with a second dosing schedule in order to enable heat transfer between the reagent injector and said injected reagent, the second dosing schedule being associated with a second range of engine operating conditions.