脱硫设施对2种燃煤锅炉排放VOCs的影响

利用GC-MS，对我国7家典型燃煤电厂和2家焦化厂燃煤锅炉在脱硫工艺设施前后排放烟气中的VOCs进行了分析，并计算了燃煤电厂锅炉的排放因子和VOCs的排放量。2种锅炉在脱硫后VOCs的浓度分别为85~1 374 μg·m⁻³和27~45 μg·m⁻³。脱硫设施对VOCs的排放影响受多种因素影响，包括脱硫设施的种类、VOCs的性质、脱硫浆液等。通过计算得到各企业的臭氧生成潜势值(OFP)，为17~2 640 μg·m⁻³，其中苯系物对臭氧生成的贡献最大。计算得到燃煤电厂的排放因子为2.37 g·GJ⁻¹，每年因火力发电排放的VOCs为4.2×10⁴ t。以上结果可为燃煤电厂的VOCs控制设备和工艺选择提供参考。

Effect of desulfurization on VOCs emission from two kinds of coal-fired boilers

The VOCs in the flue gas before and after wet flue gas desulfurization (WFGD) in 7 typical coal-fired power plants and 2 coking plants in China were investigated by GC-MS, and the emission factors and the VOCs emissions of thermal power plants were calculated. The concentrations of VOCs after WFGD in coal-fired power plants and coking plants were 85~1 374 μg·m−3 and 27~45 μg·m−3, respectively. The impact of WFGD on VOCs emissions is affected by many factors, including kinds of desulfurization, the nature of VOCs, and desulfurization water. The ozone formation potential (OFP) of each plant was calculated, which was in the range of 17~2 640 μg·m−3. Aromatic hydrocarbons contributed the most to ozone generation. The calculated emission factor of coal-fired power plants was 2.37 g·GJ−1, and the annual amount of VOCs emitted by thermal power generation is 42 000 t. Results from this research can provide reference for pollution control of VOCs in coal-fired power plants.