Characteristics of carbonyl compounds from boilers fired different types of fuel

To explore the emission characteristics of carbonyl compounds (CCs) from boilers with different fuel types, the exhausts from the stacks of 14industrial boilers, whose fuel type included coal, biomass, petroleum coke and natural gas, and 2coal-fired utility boilers were sampled in the study. 21CCs were analyzed by a PFPH-derivatization-GC/MS method. The results showed that the composition of CCs in the exhausts varied significantly among different fuel types of boilers (One-way ANOVA, F=4.458, P=0.028coal-fired utility boilers>coal-fired industrial boilers>gas-fired boilers>biomass-fired boilers, with the total mass concentrations of (6306.25±1335.35), (5745.96±2864.62), (5313.57±2959.36), (2461.38±1052.35), and (1341.18±616.46) μg/m3, respectively. Furthermore, among all types of boilers, low-molecular-mass-weight CCs, (e. g. formaldehyde, aldehyde, acetone and propanal) were the most important contributors to the total CCs of the exhaust, which occupied 87.56%, 91.36%, 92.94%, 78.70%, and 45.84% in the exhausts of petroleum-coke-fired, coal-fired utility, coal-fired industrial, gas-fired boilers and biomass-fired boilers, respectively. At last, ozone formation potential (OFP) was evaluated by maximum incremental reactivity (MIR) and total hydroxyl radical (OH) reactivity by CCs, respectively, revealing that formaldehyde, propionaldehyde, acetaldehyde are the key species with high OFP and (OH) reactivity. © 2020, Editorial Board of China Environmental Science. All right reserved.