New insight of ozone pollution impact from flare emissions of chemical plant start-up operations. (February 2019)

• Record Type: Journal Article
• Authors: Ge, Sijie; Zhang, Jian; Wang, Sujing; Xu, Qiang; Ho, Thomas
• Is Part Of: Environmental pollution. Volume 245(2019)
• Page Start: 873
• Page End: 882
• Publication Date: 2019-02
• Subjects: Ozone pollution -- Air-quality modeling -- Plant start-up -- Process dynamic simulation; Pollution -- Periodicals; Pollution -- Environmental aspects -- Periodicals; Environmental Pollution -- Periodicals; Pollution -- Périodiques; Pollution -- Aspect de l'environnement -- Périodiques; Pollution -- Effets physiologiques -- Périodiques; Pollution; Pollution -- Environmental aspects; Periodicals; Electronic journals; 363.73
• DOI: 10.1016/j.envpol.2018.11.048
• Languages: English
• ISSNs: 0269-7491

Abstract

Abstract: Flaring is a common and necessary operation for chemical industries, which is designed to manage dangerous process overpressure scenarios or to release and destroy off-spec products during chemical plant upsets or turnarounds. However, excessive flaring can emit large quantities of VOCs and NOx into the atmosphere, which will cause transient and localized ozone pollution events in the presence of sunlight. The objective of this study was to quantify the impact to regional air-quality due to flare emissions from chemical plant start-up operations through the coupling of dynamic process simulations via Aspen Plus and air-quality simulations via CAMx. Simulation results from case studies have indicated that the corresponding ozone increments can vary significantly from 0.2 ppb to 17.8 ppb under different temporal and spatial factors, including the start-up starting hour, starting day, and plant location. Additional ozone sensitivity simulations have also indicated that the corresponding ozone increments are higher when the plant is located in a VOC-limited area than that in a NOx -limited area. The results from this study have delivered a cost-effective air-quality control practice for plant start-ups with a minimum air-quality impact through selecting the optimal starting time within the allowable ranges. The practice has significant potential to benefit all stakeholders, including environmental agencies, chemical industries, and local communities. Graphical abstract: Highlights: Coupling chemical plant start-up simulation with regional air-quality modeling. Systematic study on ozone pollution due to chemical plant start-up operations. Cost-effective and environmentally benign strategy for ozone pollution reduction. Abstract : This study demonstrated a cost-effective air-quality control practice for plant start-ups with a minimum air-quality impact.