The basic processes are shown in Fig. 10.1. Personnel and equipment are transported to the site. In most cases, fire-resistant boom is deployed downwind of the spill and a tow begun. When enough oil collected in the boom, it is ignited using an igniter. The boom tow is resumed and continued until the fire is extinguished or the tow is stopped for operational reasons. The burning and progress of the tow are monitored by personnel on aircraft and on a larger ship from which an overview of the slick and conditions is possible. The monitoring crew can also direct the boom tow vessels to slick concentrations upwind. During the burn, monitoring normally includes estimating the area of oil burning at specific time intervals so that the total amount burned can be estimated. The amount of residue is similarly estimated. Particulate matter downwind might be monitored to record the possible exposure levels.

The burn could be stopped in an emergency by releasing one end of the boom tow or by speeding up the tow so that oil is submerged under the water. If the burning stops because there is not enough oil in the boom, the tow can be resumed going downwind and then turning around into the wind before reigniting. After the burn operation is finished for the day or for the single burn, the burn residue should be removed from the boom. As the burn residue is very viscous, a heavy oil skimmer may be required if there is a large amount of material. A small amount of residue can be removed by hand using shovels or sorbents.

The burning that took place at the Deepwater Horizon was an example of a successful burn campaign at sea. Indeed, there were about 400 successful burns carried out during the Deepwater Horizon spill and this removed a significant part of the oil on the water. The basic technique was to collect oil in a fire-resistant boom (hereinafter called fire boom) and then ignite the oil and slowly pull the fire boom forward to push the oil to the rear or wait if the winds and currents were doing this. The oil was spotted using a fixed-wing aircraft. Two shrimp boats (about 100-ft-long) towed about 150 m (500 ft) of fire boom at about ½ to ¾ knot to avoid loss of the oil through entrainment under the boom. The tow lines were about 100 m (about 300 ft) for the safety of the tow crews. This is shown in Fig. 10.24. Once sufficient oil had been collected for a burn and marine and air monitoring approved, ignition was requested. A small boat carrying two persons would approach from upwind and an igniter dropped over the edge of the boom. The igniters were made from a plastic jar (about 1 L) of diesel fuel, a marine flare, and some Styrofoam floats. The flare once activated burned down to the bottle of gelled diesel fuel, which started burning and acted as a primer to ignite the oil.

Once lit, the heavy, weathered oil would burn until most oil was removed. The burn was monitored from the air by trained observers and from larger vessels in the area. The amount burned was gauged by estimating the burning area in the boom and multiplying by the burning rate.

Many precautions were taken during the burn. Extensive training was given to the crews and several practice sessions were undertaken. Particulate emissions from the burns were monitored.

Oil can also sometimes be burned without containment and by using natural containment features such as oceanic fronts, ice, or shorelines to contain oil.