A review of emission characteristics and risk assessments of volatile organic compounds in petrochemical industry areas

As the petrochemical industry grows, environmental and human health issues associated with petroleum refining and chemical processes also increase. Consequently, several studies have been conducted on this topic. However, the results of the current research vary, and a comprehensive review is lacking. This study summarized the volatile organic compounds (VOCs) emission and risk assessments in the petrochemical industry based on data collected from previous studies. A discussion of VOC emission characteristics is provided. The effects of VOCs on human health, ozone formation potential (OFP), and secondary organic aerosol (SOA) are also reviewed. According to this review, the VOC emission characteristics are related to the raw materials and processes. Moreover, research methods can lead to certain biases. In entire petrochemical plants, alkanes were the largest contributors to VOC emissions, with n-pentane, n-butane, and propane frequently appearing in the top five emission lists. Among the process unit areas, alkanes were the major contributors, except for the delayed coking unit, where aromatics significantly contributed. Regarding the risks associated with VOC emissions, benzene, and 1,3-butadiene are common carcinogens impacting human health. 1,3-Butadiene, benzene, and acrolein are major contributors to noncarcinogenic risk. OFP is related to VOC emissions and their corresponding reactivities. Alkenes, alkanes, and aromatics are major contributors to OFP. Aromatics were the largest contributors to SOA concentration. In the future, research methods on the characteristics and risks of VOC emissions need to be further improved. More precise sampling techniques and advanced analytical instruments should be employed to better characterize VOC emissions. Overall, this study considered the characteristics of VOC emissions from petrochemical industrial areas, as well as the risks to the environment and health to provide a reference for the control of VOCs.