An effective way to remove oil from the surface of water is through controlled burning, called in-situ burning. In-situ burning can remove approximately 100 gallons/day/square foot of surface area under ideal conditions. By removing oil from the water surface, we are protecting birds, marine mammals, turtles, and the sensitive Florida coast from the effects of the oil spill.
Burning oil spills produces a visible black smoke plume that may be seen for many miles. The burning of oil converts oil into its primary combustion products, carbon dioxide and water, with a small percentage of unburned and residue by-products. Typically, 90-95 percent of the smoke is carbon dioxide, particulates account for 5-10 percent, with the remainder being primarily carbon monoxide, nitrous oxides and sulfur dioxide. These emissions are rapidly dispersed and diluted downwind of the burn. For this reason, in-situ burning is conducted only when the winds are blowing away from or at sufficient distance from population centers.
In-situ burning is always conducted under controlled conditions. First, two ships deploy a specially constructed fire boom between them, one end attached to each ship. The boom can be anywhere between 300-500 feet long. The boom takes on a U configuration as it is towed by the two ships at about three-fourths of a knot. Oil is gathered inside the U, moved to a location away from the main spill and is set on fire. By controlling the rate of speed of the ships, the rate of the burn can be increased, decreased, or even extinguished. The residues left in the boom after the burn is over will be recovered by conventional means.
Ignition of the oil can be accomplished in a number of different ways. One way is with a Heli-torch. A Heli-torch is a device that is attached to a helicopter and aerial releases burning gelled fuel on the oil. Additionally, specially designed pyrotechnic devices (such as a Pyroid igniter or Dome igniter) can be released by hand from one of the ships towing the boom and allowed to float back to the oil, or it may be dropped by a helicopter on the oil.
In-situ burning can only be conducted when the weather conditions are favorable. Generally, if the sea is two to three feet or less, in-situ burning is possible. If the seas get too high, in-situ burning will be discontinued.
Florida Department of Environmental Protection Office of Emergency Response (850)245-2010
September 24, 2019 - 11:22am
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The Florida Department of Environmental Protection is the state’s lead agency for environmental management and stewardship – protecting our air, water and land. The vision of the Florida Department of Environmental Protection is to create strong community partnerships, safeguard Florida’s natural resources and enhance its ecosystems.