TY - GEN
T1 - The research of the influence of primary air ratio on the combustion in a lignite-fired Ultra Supercritical boiler
AU - Sha, Long
AU - Liu, Hui
AU - Jiao, Feng
AU - Cao, Qingxi
AU - Xin, Nana
AU - Wu, Shaohua
PY - 2009
Y1 - 2009
N2 - The Computational Fluid Dynamics (CFD) code PHOENICS was applied to evaluate the combustion process in the furnace of a 1000MW dual circle tangential firing single furnace lignite-fired Ultra Supercritical (USC) boiler. The influence of different primary air ratios (35%, 39% and 43%) on the flow and mixing characteristics of the gas-solid two-phase flow and the combustion process in the furnace was focused on. The results indicate that in the furnace with double tangential firing, the flow field shows two well-symmetrical ellipses at different primary air ratios. The surface temperatures of the burners at which, the long axis of the ellipses pointed, are much higher than those in the other four corners. Thus the phenomena of 'Hot corners' and 'Cold corners' arise. In practical operating, the flow erodes the walls in the hot corner which may lead to high temperature corrosion and slagging. With the increase of primary air ratio, the average concentration of NO x at the outlet of furnace rises while the char distributions in the furnace are similar. By the comparisons of the characteristics of the airflow, the temperature distributions, the NO x formation amounts and the char burnout rates, the situation with the 35% primary air ratio is preferable. The results of this paper have great value because of the support they lend to the design of USC lignite-fired boilers.
AB - The Computational Fluid Dynamics (CFD) code PHOENICS was applied to evaluate the combustion process in the furnace of a 1000MW dual circle tangential firing single furnace lignite-fired Ultra Supercritical (USC) boiler. The influence of different primary air ratios (35%, 39% and 43%) on the flow and mixing characteristics of the gas-solid two-phase flow and the combustion process in the furnace was focused on. The results indicate that in the furnace with double tangential firing, the flow field shows two well-symmetrical ellipses at different primary air ratios. The surface temperatures of the burners at which, the long axis of the ellipses pointed, are much higher than those in the other four corners. Thus the phenomena of 'Hot corners' and 'Cold corners' arise. In practical operating, the flow erodes the walls in the hot corner which may lead to high temperature corrosion and slagging. With the increase of primary air ratio, the average concentration of NO x at the outlet of furnace rises while the char distributions in the furnace are similar. By the comparisons of the characteristics of the airflow, the temperature distributions, the NO x formation amounts and the char burnout rates, the situation with the 35% primary air ratio is preferable. The results of this paper have great value because of the support they lend to the design of USC lignite-fired boilers.
KW - Combustion
KW - Dual circle tangential firing
KW - NO
KW - Numerical simulation
KW - Primary air ratio
UR - https://www.scopus.com/pages/publications/84869978521
U2 - 10.1109/APPEEC.2009.4918904
DO - 10.1109/APPEEC.2009.4918904
M3 - 会议稿件
AN - SCOPUS:84869978521
SN - 9781424424870
T3 - Asia-Pacific Power and Energy Engineering Conference, APPEEC
BT - 2009 Asia-Pacific Power and Energy Engineering Conference, APPEEC 2009 - Proceedings
T2 - 2009 Asia-Pacific Power and Energy Engineering Conference, APPEEC 2009
Y2 - 27 March 2009 through 31 March 2009
ER -