화학공학소재연구정보센터
Journal of the Institute of Energy, Vol.75, No.505, 100-106, 2002
Optimisation of advanced coal reburning for NOx control
An experimental study of advanced reburning was carried out in a down-fired 20-kW combustor using a selection of power-station pulverised coals as reburn fuel. The effect of reburn fuel fraction, initial NOx concentration and the nitrogen stoichiometric molar ratio (NSR) are reported in detail as well as the optimum configurations for advanced reburn. The effect of fuel properties such as fuel nitrogen and volatile matter was also assessed. The experimental results show that advanced reburning can result in an additional 15-25% improvement in NO reduction over and above that which can be achieved without selective non-catalytic reduction. With all operating parameters optimised within normal operating limits, it was possible to reduce the NO emission from the primary zone in total by typically around 85%. NOx reduction increased with increasing NSR and ammonia slippage was very low. The most important parameter was found to be the ammonia injection location, which is strongly influenced, by the coal type and the reburn fuel fraction.