Volume 12, No. 3, June 2012, Pages 379-386 PDF(892 KB)
Development of an Innovative Circulating Fluidized-Bed with Microwave System for Controlling NOx
Yuan-Yi Chang1, Yeou-Lih Yan2, Chao-Heng Tseng1, Jin-Yuan Syu1, Wen-Yinn Lin1, Yu-Chun Yuan1
1 Institute of Environmental Engineering and Management, National Taipei University of Technology, 1, Sec. 3, Chung-hsiao E. Rd., Taipei, 10608, Taiwan
2 Department of Safety, Health and Environmental Engineering, National United University, 1, Lienda, Miaoli, 36003, Taiwan
Selective catalytic reduction (SCR) and selective non-catalytic reduction (SNCR) technique are widely used to control nitrogen oxides emissions. However, both techniques have a general shortcoming known as NH3 slip.
This research introduced the design of activated carbon in a circulating fluidized-bed with microwave system and developed an innovative de-NOx technique. The whole system demonstrated the capability and advantage of reducing reductant cost and continuous process. The experiments investigated microwave to regenerate activated carbon (AC) in order to increase adsorption and destruction efficiency while reducing energy consumption. In the NOx abatement process, activated carbon adsorbed NO and NO2 and then utilized microwave heating technology to regenerate itself because of microwave’s high energy utilization and strong penetration ability. The specific surface areas of AC increased from 673.03 to 834.52 (m2/g) when microwave power was increased from 0 to 550 W, respectively, in this study. Through increasing the specific surface area, the microwave treatment further improved the NOx adsorption capacity and rate.
In consequence, the results indicated that destruction efficiency of NO and NO2 at 200 ppm could reach about 80% with microwave power of 350 W and above 85% of 550 W. The destruction efficiency at 550 W for NOx was about 77%.
Nitrogen oxides; Microwave; Activated carbon; Circulating fluidized-bed.