An Estimate of Mercury Emissions to the Atmosphere from Petroleum

Wilhelm, S. M., "An Estimate Mercury Emissions to the Atmosphere from Petroleum", Environ. Sci. Tech., Vol. 35, 24:4704 (2001).

ABSTRACT

An estimate of the contribution of mercury to the atmospheric environment from petroleum processed in the United States is constructed from recent data. The estimate is based on a mass balance approach for mercury in crude oil, in refined products and in waste streams (air, water, solid waste) from refineries. Although there are insufficient data at present to have a high degree of confidence in the mean amount and range of mercury concentrations in crude oil or in refined products, the framework of the estimate should assist direction for the acquisition of additional data.

Based on selected data that put the estimated mean concentration of total mercury in crude oil close to 10 ppb, it is calculated that the total amount of mercury in U.S. petroleum processed yearly is slightly over 8,000 kg/year. Of this amount, approximately 6,000 kg/year is estimated to be emitted to the atmosphere from combustion of liquid hydrocarbon fuels, which represents about 10 percent of the U.S. yearly emission rate of atmospheric mercury from coal combustion. The material balance predicts that the amount of mercury in air emissions from all U.S. refineries is on the order of 1,500 kg/year based on the assumption that fugitive mercury emissions from refineries are negligible.

Atmospheric emissions of mercury from fuel oil burned in the U.S. are estimated in the U.S. EPA Mercury Report to Congress to be approximately 10,000 kg/year and this estimate may be in error on the high side by a factor of 3 to 10. If the mean amounts of mercury in U.S. distillate and residual fuel oils are in the range of 5-15 ppb, as suggested by more recent data, then U.S. fuel oil combustion should contribute no more that about 1,000 to 3,000 kg/year (emission ratio = 1) of mercury to the atmospheric burden.



Order the entire paper