Review of Emissions from Oil Fires

Abstract

The concern over emissions often dominates concerns regarding in-situ burning of oil spills. This paper reviews the results of emission measurement from both test fires and full-scale fires. More than 50 meso-scale burns of crude and diesel were conducted to study various aspects of diesel and crude oil burning in-situ. Extensive sampling and monitoring of these burns were conducted at downwind stations, and in the smoke plume. Later, the burning characteristics of heavy oils and emulsified heavy oils were studied. More than 15 meso-scale burns of these heavy oils were conducted. Measurements of the volatile components and particulates were made. Finally, some measurements were made on the in-situ burns carried out during the 2010 Deepwater Horizon spill.In summary, these measurements found that PAHs were found to be lower in the soot than in the starting oil, although somewhat higher concentrations of the larger molecular PAHs were found in the soot and residue. Particulates in the air were measured by several methods and were only found to be greater than recommended exposure levels at ground level if an inversion was present . Combustion gases including carbon dioxide and carbon monoxide did not reach exposure level maximums. Volatile organic compound (VOCs) emissions were found to be extensive from fires, but the levels were lower than an evaporating crude oil spill. Carbonyls, including aldehydes and ketones, were found to be higher from diesel burns than from crude oil burns.Measurement of the highly toxic compounds, dioxins and dibenzofurans, were made during the test fires. None were found. Similar results were found for the 2010 Deepwater Horizon burns.Water under the burns was analysed in the case of some of the test fires; no compounds of concern could be found at the detection levels of the methods. The burn residue was analysed for the same compounds as the air particulate samples. The concentrations of PAHs were lower in the residue than in the original oil, although the concentrations of some higher molecular weight species increased slightly. Furthermore, in all burns it was found that emissions of any type, did not exceed that of health concerns at distances greater than about 1 km, if the smoke plume did not impact the ground.