Fine particle emission profile for a large coke production facility based on highly time-resolved fence line measurements

Abstract

This paper presents a fine particle emission profile for a large metallurgical coke production facility. The profile is developed from highly time-resolved, ambient air quality measurements made at a fence line site adjacent to the plant. A fence line approach was employed because the coke plant has hundreds of stacks and other emission points, making it difficult to develop an integrated, facility-wide emission profile using stack sampling techniques. Continuous or semi-continuous measurements of PM 2.5 mass, PM 10 mass, SO 2, NO x , organic and elemental carbon (OC and EC), particle size and number, 11 trace metals, wind direction and wind speed were made. Background pollutant levels were also measured. A combination of highly time-resolved meteorology and air quality data were used to determine when the coke facility emissions influenced the sampling site. Concentrations for most pollutants at the fence line site were one to two orders of magnitude higher than background levels when the facility plume heavily influenced the fence line site. Highly time-resolved measurements are essential to resolve these relatively short-duration, large spikes in pollutant concentrations. Simply measuring wind direction is insufficient. From these highly time-resolved measurements an average PM 2.5 emission profile for the coke facility was developed. The profile is dominated by OC (40%±9% of PM 2.5 mass emissions) and EC (25%±5% of PM 2.5 mass emissions). Significant contributions of certain trace metals were also observed, including As, Zn, Se, and Pb. The particle emissions are dominated by the fine fraction, with PM 2.5 estimated to contribute 84%±14% of the PM 10 mass.