RESEARCH ON CHARACTERISTICS AND REACTIVITY OF VOLATILE ORGANIC COMPOUNDS EMISSION FROM A COKING ENTERPRISE

The study selected a typical coking enterprise to carry out the characterization of unit VOCs emissions for four production units with high active volatile organic compounds(VOCs) components, namely, phenol refining, Gumarone, asphalt coke, and tar naphthalene. Unit VOCs exhaust was collected using a Suma tank, and 106 VOCs components were characterized and quantified by gas chromatography-mass spectrometry(GC-MS), and the contribution of each unit's VOCs emission to the generation of O₃ in the atmosphere was calculated using the maximum incremental reactivity(MIR). The results showed that: 1) aromatic hydrocarbons, halogenated hydrocarbons, and oxygenated VOCs(OVOCs) were the main featured components of the four units, and the sum of mass fractions accounted for 92.33% to 95.38%. 2) The sum of mass fractions of the top 10 VOCs species ranked by the four units ranged from 90.45 to 93.46%. Among them, benzene, acetone, methylene chloride, ethanol, and toluene were the characteristic species of VOCs emission from coking enterprises. 3) The ozone generation potential(OFP) values of the four units were 278.73 μg/m³ to 426.95 μg/m³, in an order of tar naphthalene unit(426.95 μg/m³)>phenol refining unit(410.43 μg/m³)>asphalt coke unit(294.36 μg/m³)>Gumarone unit(278.73 μg/m³). 4) The contribution of the top 10 species of the four units to OFP ranged from 96.24% to 97.97%. Benzene, toluene, m/p-xylene, ethylene, and acetone were the key active species in the industry. 5) Different coking production units had different species characterizing VOCs emissions, and the active species contributing to OFP varied. The largest active species contributing to OFP from phenol refining unit was m/p-xylene, the largest active species contributing to OFP from Gumarone and asphalt coke unit was ethylene, and the primary active species from tar naphthalene unit was toluene. It is recommended that targeted VOCs emission reduction strategies be formulated based on key active components screened in the study. To control the contribution of VOCs emissions to the OFP in the coking industry, priority should be given to the adoption of targeted measures to control the emissions of characteristic pollutant components in different installation areas, such as focusing on strengthening the collection and treatment of respiratory gases from the storage tanks of reactive materials, and the effectiveness of the implementation of the LDAR in the installations involving reactive materials.