Abstract
Aimed at the selective catalytic reduction (SCR) DeNOx system of a 660 MW coal-fired power station, which is limited by low denitrification efficiency, large ammonia consumption and over-high ammonia escape rate, numerical simulations were conducted by employing STAR-CCM+ (CFD tool). The simulations results revealed the problems existed in the SCR DeNOx system. Aimed at limitations of the target SCR DeNOx system, factors affecting the denitrification performance of SCR, including the structural parameters and ammonia injected by the ammonia nozzles, were optimized. Under the optimized operational conditions, the denitrification efficiency of the SCR system was enhanced, while the ammonia escape rate was reduced below 3ppm. This study serves as references for optimization and modification of SCR systems.
Highlights
Owing to the “poor in oil and gas, rich in coal” characteristic of China, the coal-fired power generation dominates the domestic power industry [1]
The distributions of velocity and concentration obtained by the actual operational data of the selective catalytic reduction (SCR) DeNOx system were consistent with those obtained by numerical simulations, despite slight errors induced by equipment
The following conclusions can be obtained: (1) Field distributions obtained by numerical simulations are consistent with the actual operational data, indicating th at numerical simulations can predict distributions of flue gas in the catalyst layer for design of SCR systems, facilita ting optimization of denitrification by SCR systems by elim inating non-uniform flue gas distribution and unexpected w ear
Summary
Owing to the “poor in oil and gas, rich in coal” characteristic of China, the coal-fired power generation dominates the domestic power industry [1]. In 2012, the domestic power generation was 4.97 trillion kW∙h and the coal-fired power generation was 3.91 trillion kW∙h (78.6%) [2]. Optimization methods of coal-fired furnaces reported previously do not meet requirements by current standards [3]. Among various NOx treatment methods, the SCR denitrification technology is one of the most widely applied and most effective methods [4]. The mechanism of SCR denitrification is that reducers (e.g., NH3 and urea) selectively react with NOx to generate N2 and H2O under prescribed catalysts. In denitrification processes by the selective catalytic red uction (SCR), the concentration distribution of reducers in S CR reactor and airflow distribution has a direct effect on its denitrification efficiency. The flow fields of the sy stem were analyzed using computational fluid dynamic (CF D) methods [5-6]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
