Emission behavior, environmental impact and priority-controlled pollutants assessment of volatile organic compounds (VOCs) during asphalt pavement construction based on laboratory experiment.

Volatile organic compounds (VOCs) release from asphalt pavement construction is a potential emission source. The detailed emission behaviors were simulated in the laboratory, and the corresponding environmental impact was investigated as well. A set of dedicated devices were applied to mirror 3 representative scenarios namely mixture plant, transportation and paving processes with VOCs emission concentrations varied from 4.24 mg/m3 to 104.16 mg/m3. Ozone formation potential (OFP) and secondary organic aerosol (SOA) were built to evaluate the environmental impact, indicating that the reactive ability differed in the specified substances. The alkenes (n ≤ 4) and aldehydes, alkanes (n ≥ 6) and alkylbenzenes with relative lower concentration were the main sources for the OFP and SOA generation, and they contributed to more than 62% OFP and 97% SOA respectively. The top 10 contributors to concentration, OFP and SOA had been identified. For the complex species existed in VOCs emission and the lack of VOCs control standards, this study provided possible access to screen priority-controlled pollutants based on information entropy method, in terms of both environmental and human health impact. In addition, the first-class priority-controlled species had been determined, urgently needing more attention in the future VOCs management during asphalt pavement construction.