Fuel, Vol.225, 554-562, 2018
Emission of volatile organic compounds (VOCs) during coal combustion at different heating rates
The emission of volatile organic compounds (VOCs) during coal combustion at different heating rates in a power plant boiler, a drop tube furnace and a TGA reactor was studied. TD-GC/MS and online FTIR were used to measure VOCs during coal combustion. This study shows that the combustion temperature has a distinct effect on VOC composition. Larger VOC concentrations were detected in the flue gas collected at higher furnace temperatures in a drop tube furnace. Higher furnace temperatures led to a faster heating rate and a shorter residence time for the flue gas in the furnace, resulting in increased VOC generation. In the power plant boiler study, passing the flue gas through the SCR system increased the oxidation of hydrocarbons and reduced VOC emissions by 61%. Moisture effects in the WFGD and WESP systems reduced the VOCs by 10-15%. The ESP might release a small amount of the condensed VOCs on the surface of the fly ash. Overall, the APCD systems in a power plant can reduce VOC emissions. This study used measurements obtained during coal combustion at three different heating rates to generate a complete VOC emission profile. In addition, this study demonstrates the ability of air pollution control devices to reduce VOC emissions.