Development of an Innovative Circulating Fluidized-Bed with Microwave System for Controlling NOx

Received: November 25, 2011
Revised: February 2, 2012
Accepted: February 2, 2012
Download Citation: RIS|BibTeX|https://doi.org/10.4209/aaqr.2011.11.0213  

Cite this article:
Chang, Y.Y., Yan, Y.L., Tseng, C.H., Syu, J.Y., Lin, W.Y. and Yuan, Y.C. (2012). Development of an Innovative Circulating Fluidized-Bed with Microwave System for Controlling NOx. Aerosol Air Qual. Res. 12: 379-386. https://doi.org/10.4209/aaqr.2011.11.0213

ABSTRACT

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-NO_x 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 NO_x 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 NO_x 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 NO_x was about 77%.

Keywords: Nitrogen oxides; Microwave; Activated carbon; Circulating fluidized-bed