Characterization of Emissions and Residue from Measures to Improve Efficiency of In Situ Oil Burns

Abstract

Simulated in situ oil burning tests were conducted in a 14 m × 2.4 m × 2.4 m tank to characterize variations in boom length/width aspect ratios, the use of injection air, nozzle angle, and presence or absence of waves on combustion efficiency. Tests were done with approximately 35 L of unweathered Alaska North Slope oil within an outdoor, fresh water, 63 m3 tank. The combustion plume was sampled with a crane-suspended instrument system. Emission measurements quantified carbon monoxide, carbon dioxide, particulate matter less than 2.5 μm (PM2.5), and total carbon. Post-burn residue samples were collected with pre-weight oil absorbent to determining oil mass loss and total petroleum hydrocarbons (TPH) in the residue. Plume measurements of modified combustion efficiencies (MCET) ranged from 85% to 93%. Measurement of residual, unburnt oil showed that the oil mass loss ranged from 89% to 99%. A three-fold variation in PM2.5 emission factors was observed from the test conditions where the emission factors decreased with increased MCE. The TPH in the residue were found to decrease with increased oil mass loss percentage. In terms of combustion efficiency and oil consumption, results suggest that the most effective burns were those that have high length to width boom aspect ratios and added injection air.