Air Toxic Emissions Characterization of Natural Gas Processing Plants

Abstract

Abstract The U.S. Environmental Protection Agency (EPA) is developing air toxic regulations for oil and natural gas production, with the proposed rule scheduled for promulgation in 1997. The EPA is also scheduled to promulgate air toxic regulations for industrial combustion sources by the year 2000. In addition, several states have air toxic regulatory initiatives that affect the gas industry. Because these regulations could have large economic and operational impacts on the gas industry, the Gas Research Institute (GRI) has initiated a multiphase research program. One of the objectives of this program is to determine potential sources of air toxic emissions in the natural gas industry, the quantities of air toxics emitted, and individual species emitted from typical equipment. The primary objective of the testing conducted in this program at gas processing plants was to assess potential air toxic and criteria pollutant emissions associated with combustion equipment, including characterizing the following emission sources: internal combustion (IC) engines, gas turbines, incinerators, heaters, and boilers. The pollutant classes evaluated include aldehydes, criteria pollutants, volatile organic compounds, semi-volatile organic compounds, metals, and reduced sulfur compounds. In addition, unit operational data were obtained during testing. To date, eight field measurement campaigns have been conducted at natural gas pipeline and gas processing facilities. Three (3) of these campaigns involved testing at sour gas processing plants, while two (2) other campaigns focused on emission sources at sweet gas plants. The emission test results for these programs are summarized in this paper. In addition to emissions characterization, the effects of maintenance and performance tuning on emission levels was investigated during one campaign. Results on emissions, efficiency, and cost impacts associated with maintenance and tuning activities conducted on three engines, two incinerators, and two process heaters are reported.