Recovery of Oil Trapped in Ship-Wrecks: the DIFIS Concept
A method for the prompt and cost-effective intervention and remediation of tanker wrecks dealing with eventual leaks and recovering the fuel trapped in their tanks, even at considerable depths, is described. The method is of general applicability as long as the trapped pollutant does not dissolve and is of lower density than sea water. It relies on gravity to channel the flow of spilt fuel to-wards the surface. Instead of channeling the flow direct-ly to the surface, the fuel-water mix is directed to a buffer reservoir/separator some 30-50 m below the sea surface so as not to be affected by rough weather. This is achieved by means of a light, quickly deployable flexible structure that should stay in place until all the tanks of the wreck are emptied and the pollution threat eliminated. The buffer reservoir, into which the spilt fuel is channelled, is provided with standard equipment through which shuttle vessels, weather permitting, can recover the fuel rapidly, using standard off-shore equipment and procedures.