Reagent dosing system and method of dosing reagent
View Patent ↗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.
1. A reagent dosing system for dosing a reagent into the exhaust gas stream of an internal combustion engine, the system comprising:
a reagent tank for storing a supply of reagent;
an injector module comprising 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.
2. A system according to claim 1 , wherein the dispenser and the metering pump are integrated within the same unit.
3. A system according to claim 1 , wherein the priming pump is operable at or during a start-up mode.
4. A system according to claim 1 , wherein the priming pump is operable continuously or intermittently during running of the engine.