Pollutant emission performance of additive-upgraded high-sulfur coal in CFB combustion
LIANG Bin
LIU Zhongpan
WU Qiong
ZHENG Yuangang
BAI Haolong
SONG Hua
WANG Chuanzhi
LAN Tian
Abstract：A technology was proposed to upgrade the high-sulfur coal by utilizing the composite chemical additives.The technology aimed at achieving SO2 emission no higher than the base-coal when it was co-fired with the additive-upgraded high sulfur(AUHS) coal.Furthermore,when the AUHS was co-fired with the base-coal,the SO2 produced from both the base-coal and high sulfur coal could be reduced to meet the strictest emission standard,e.g.ultra low emission standard(i.e.＜35 mg/Nm3).To validate the technologic concept,experimental tests with a base-coal,a high-sulfur coal and their blend were combusted in a 1 MW pilot circulating fluidized bed(CFB)test facility.The results show that the SO2 emission is almost same as that of base-coal when 30％ high-sulfur coal co-fired with the additives.Further experiments demonstrate that co-firing the additive-containing high-sulfur coal with a blend of high sulfur coal and basecoal(total high sulfur coal is 30％) with an overall stoichenmistric ratio of 2.5 reduces the SO2 emission to 21.5 mg/Nm3.It is lower than the current national ultralow emission standard of 35 mg/Nm3.The in-situ sulfur removal efficiency is 98.8％.In addition,the additives used to upgrade the high sulfur coal also inhibit the production of other gaseous pollutants,such as N2 O,NH3,HCN,HC1,HF,CH4 and CO reflected by the lower emissions of these pollutants.The investigation confirms that the technology presenting in this study is one of the most effective and economic solutions for clean utilization of high sulfur coals.
Keywords：circulating fluidized bedcoal combustionhigh-sulfur coalupgradepollutant emission
Publication Date：2017-01-01