Emission Characterization and Ozone Formation Potential of VOCs During the Coking Process

The concentration and chemical speciation of volatile organic compounds(VOCs) was quantitatively analyzed from three kinds of smoke,which were the fugitive emissions gas,the dust removing station smoke,and the coke quenching smoke,respectively.And two types of coke oven were test,which were top charging coke oven and tamping coke oven.In addition,Maximum Increment Reactivity(MIR) and OH loss rate(L^OH) was used to quantify the ozone formation potential(OFP) and reaction activity of various VOCs species.According to the measurement results,the concentration of VOCs in the fugitive emissions reaches to hundreds ppb,and the VOCs species in the fugitive gas are similar between top charging coke oven and tamping coke oven.Ethane,ethylene,benzene are the major VOC species,and their volume fraction percentages are 22.7% ± 2.1% and 24.2% ± 0.6% 、44.3% ± 1.9% and 54.1% ± 2.0% 、14.3% ± 3.8% and 7.3% ± 0.5%,respectively.Decane,ethylene,acetylene are the major VOC species in the dust removing station smoke.Their volume fraction percentages in the top charging coke oven and tamping coke oven are 6.5% ± 2.4% and 20.3% ± 7.5%,29.4% ± 3.3% and 39.8% ± 4.2%,31.6% ± 3.8% and 15.0% ± 3.8%,respectively.In thecoke quenching smoke,decane is the major VOC species,and its volume fraction percentage is 53.8% ± 6.3%.The alkenes especially ethylene and propene in the fugitive emissions gas and the dust removing station smoke,the alkanes especially decane in the coke quenching smoke have the highest ozone formation potential in the coking process.