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Experimental Study on DeNOx Characteristics of Urea-SCR System  

Ham, Yun-Young (Department of Mechanical & Automotive Engineering, Woosuk University)
Lee, Seong-Ho (SK Energy Corporation)
Jung, Hong-Seok (SK Energy Corporation)
Shin, Dong-Hyun (SK Energy Corporation)
Publication Information
Transactions of the Korean Society of Automotive Engineers / v.17, no.2, 2009 , pp. 180-186 More about this Journal
Abstract
To meet the NOx limit without a penalty of fuel consumption, urea SCR system is currently regarded as promising NOx reduction technology for diesel engines. SCR system has to achieve maximal NOx conversion in combination with minimal $NH_3$ slip. In this study, as a basic research to develop an algorithm for urea injection control, the characteristics of engine out NOx emission and behavior of NOx reduction during steady-state and transient conditions were investigated using 2L DI diesel engine. Test results show that on increasing the catalyst temperature the variations in the outlet NOx concentration are faster and maximal allowable $NH_3$ storage exponentially decreases. For change from a low to high engine load, it can be seen that a few seconds after load-step is required to reach full NOx conversion and the adsorbed amount of $NH_3$ at lower temperature desorb during the next temperature increase, causing $NH_3$ slip. Engine out NOx emission needs to be corrected because NOx emissions just after step load is lower than that of steay state condition.
Keywords
Nox; Urea; SCR(Selective Catalyst Reduction); $NH_3$; steady state condition; transient condition;
Citations & Related Records
Times Cited By KSCI : 1  (Citation Analysis)
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