Exhaust fluid dosing control system and method

A method for delivering an exhaust fluid reductant solution to an exhaust flow upstream of a selective catalytic reduction (SCR) apparatus, the method comprising:

• monitoring a concentration percentage of urea in the reductant solution disposed in a reductant container or inline between the reductant container and a reductant solution injector;
• based on the monitored concentration percentage of urea in the reductant solution, adjusting a dosing of the reductant solution to be injected into the exhaust flow upstream of the SCR apparatus;
• injecting the adjusted dosing of the reductant solution into the exhaust flow upstream of the SCR apparatus;
• monitoring a level of NOx or NH3 emission in the exhaust flow downstream of the SCR apparatus and verifying from the monitored level of NOx or NH3 emissions an appropriate dosing of the reductant solution into the exhaust flow upstream of the SCR apparatus;
• wherein the adjusting the dosing of the reductant solution to be injected comprises adjusting the nominal dosing to establish a quality sensed modified dosing;
• and
• wherein the injecting the adjusted dosing comprises injecting the quality sensed modified dosing.

A vehicle, comprising:

• an internal combustion engine;
• an exhaust system comprising an exhaust flow port configured and disposed to receive exhaust flow from the engine, and a selective catalytic reduction (SCR) apparatus disposed in downstream flow communication with the exhaust flow port;
• and
• a dosing control system comprising:
• a reductant tank operable to contain a reductant solution comprising urea;
• an injector disposed in operable communication between the reductant tank and the SCR apparatus, the injector being operable to inject the reductant solution from the reductant tank into a flow of exhaust upstream of the SCR apparatus;
• a urea quality sensor (UQS) configured and disposed to sense a concentration of urea in the reductant solution;
• a control module disposed in signal communication with the UQS and in operable communication with the injector, the control module comprising a processing circuit responsive to executable instructions to adjust a dosing of the reductant solution injected by the injector based on a concentration of urea in the reductant solution;
• and
• wherein the processing circuit is further responsive to executable instructions which when executed by the processing circuit facilitates an upward adjustment of the dosing of the reductant solution in response to a downward change in the concentration of urea in the reductant solution.

A non-road or stationary device, comprising:

• an internal combustion engine;
• an exhaust system comprising an exhaust flow port configured and disposed to receive exhaust flow from the engine, and a selective catalytic reduction (SCR) apparatus disposed in downstream flow communication with the exhaust flow port;
• and
• a dosing control system comprising:
• a reductant tank operable to contain a reductant solution comprising urea;
• an injector disposed in operable communication between the reductant tank and the SCR apparatus, the injector being operable to inject the reductant solution from the reductant tank into a flow of exhaust upstream of the SCR apparatus;
• a urea quality sensor (UQS) configured and disposed to sense a concentration of urea in the reductant solution;
• a control module disposed in signal communication with the UQS and in operable communication with the injector, the control module comprising a processing circuit responsive to executable instructions to adjust a dosing of the reductant solution injected by the injector based on a concentration of urea in the reductant solution;
• and
• wherein the processing circuit is further responsive to executable instructions which when executed by the processing circuit facilitates an upward adjustment of the dosing of the reductant solution in response to a downward change in the concentration of urea in the reductant solution.