不同燃料类型锅炉羰基化合物的排放特征

为探究不同燃料类型锅炉羰基化合物排放特征，选取以煤、生物质、石油焦和天然气为燃料的14台工业锅炉和2台燃煤电站锅炉作为研究对象，采用气袋-PFPH衍生-GC/MS方法采集和分析烟气中的21种羰基化合物.结果表明，不同燃料类型锅炉烟气中羰基化合物呈现明显差异（One-way ANOVA，F=4.458，P=0.028<0.05），其中羰基化合物质量浓度（9%基准氧量）排序是石油焦 > 电站锅炉 > 煤 > 天然气 > 生物质，分别为（6306.25±1335.35），（5745.96±2864.62），（4784.85±1698.20），（3589.51±1534.676），（1341.18±616.46）μg/m³.不同燃料类型的锅炉烟气中羰基化合物组分特征有明显差异性，但甲醛、乙醛、丙酮和丙醛等低分子量的羰基化合物均占比较大，燃石油焦、燃煤电站、燃煤、燃天然气和燃生物质锅炉中低碳羰基化合物总占比分别达到87.56%，91.36%，92.94%，78.70%和45.84%.最后，采用最大增量反应活性（MIR）和OH消耗速率评价烟气中羰基化合物物种的化学反应活性，结果表明，甲醛、丙醛、乙醛等低碳羰基化合物为关键活性物种.

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=0.028<0.05). The total mass concentration of CCs (based on 9% oxygen content) was ranked as petroleum-coke-fired boilers > coal-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.