Mobile diesel selective catalytic reduction systems and methods

A method for reducing NOx emissions in diesel engine exhaust installed in a vehicle, comprising:

• determining at least one engine operating parameter for each of a plurality of engine operating conditions generated during normal operation of said vehicle;
• temporarily installing a NOx detector for detecting respective NOx emissions at each of said engine operating conditions;
• developing an injection strategy based on said at least one engine operating parameter at said respective operating condition of said vehicle and said respective detected NOx emissions;
• removing said NOx detector responsive to said development of said injection strategy;
• controlling the injection of a reagent into the exhaust at a variable flow rate in order to reduce NOx emissions at said various operating conditions in accordance with said injection strategy;
• wherein:
• said variable flow rate of said reagent is controlled by a reagent injection controller in accordance with said injection strategy based on input of one or more of said engine operating parameters.