Photochemical ozone formation from petroleum refinery emissions

Abstract

Atmospheric emissions from the Marathon oil refinery at Robinson, Illinois were investigated during June and July 1977. Surface and aerial measurements were used to provide an integrated, three dimensional monitoring network. Concentrations of ozone, oxides of nitrogen, sulfur dioxide, methane, carbon dioxide, individual non-methane hydrocarbons and halocarbons were recorded on a routine basis. In addition, meteorological parameters such as wind speed, wind direction, solar radiation and mixing height were also measured. The field monitoring study focused on three major areas: 1. (1) characterization of gaseous components within the refinery effluent, especially nonmethane hydrocarbons and nitrogen oxides; 2. (2) natural sunlight bag irradiation experiments to examine ozone forming potential of refinery emissions and 3. (3) aerial measurements of changes in plume chemistry during the first six to eight hours of transport. Results indicate levels of hydrocarbons and nitrogen oxides were elevated downwind of the refinery. Concentrations within the effluent exceeded background values by as much as 300- and 10-fold, respectively. Irradiations of captured refinery emissions suggest excess photochemical ozone can be produced in the first 6 h, with amounts varying according to NMHC/NO x , ratios and initial NMHC concentrations. Real-time measurements on board the aircraft documented instances of ozone buildup in the refinery plume as it drifted downwind.