Large-Scale Field Experiments on Enhancing In-Situ Burning with Fire Whirls

Area of Science:

• Combustion science
• Environmental engineering
• Fluid dynamics

Background:

• Fire whirls show promise for cleaner, efficient combustion in applications like oil spill remediation.
• Existing research on fire whirl emissions is limited, primarily from small-scale lab experiments.

Purpose of the Study:

• To investigate the potential of fire whirls for enhancing in-situ burning of crude oil spills.
• To address a research gap by conducting large-scale controlled fire whirl experiments and comparing them to pool fires.

Main Methods:

• Conducted a large-scale experiment using a 1.5-meter crude oil pool with varying slick thicknesses (15 mm, 40 mm) on water.
• Generated fire whirls within a 5-meter-tall, three-wall structure under different wind conditions.
• Measured flame geometry, velocity, temperature, heat flux, mass consumption, and emissions, comparing results to standard pool fires.

Main Results:

• Fire whirls exhibited nearly double the flame height of pool fires, increasing burning rates by 40% and reducing soot emissions by 40%.
• Achieved 95% fuel consumption efficiency in a 15 mm slick thickness fire whirl, but premature extinguishment occurred in thicker slicks (40 mm).
• Observed that fire whirl efficiency is currently limited to calm ambient conditions.

Conclusions:

• Fire whirls demonstrate superior performance over pool fires for in-situ burning, particularly in reducing emissions.
• Optimizing fire whirl configurations for large-scale oil spills requires further research into ambient conditions, scaling, and boilover effects.
• Continued research is crucial to enhance fire whirl efficacy and mitigate detrimental emissions in real-world scenarios.