Recovery of Oil Trapped in Ship-Wrecks: The Difis Concept

Abstract

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 towards the surface. Instead of channeling the flow directly 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.

Recovery of oil‐pollutant from shipwrecks: DIFIS project

“…It is placed of about 30 m below the sea surface so that it is not affected by the weather conditions (sea waves, wind resistance) and it is designed to have large capacity and positive buoyancy. The DIFIS structure consists of seven basic components which are (Cozijn et al, 2008):…”

“…It is placed of about 30 m below the sea surface so that it is not affected by the weather conditions (sea waves, wind resistance) and it is designed to have large capacity and positive buoyancy. The DIFIS structure consists of seven basic components which are (Cozijn et al , 2008):The Buffer Bell (BB): a tank made of metal or composite for the temporary storage of recovered oil (Figure 1). The riser tube (RT): a vertical lightweight pipe for the connection of the Buffer Bell to the dome covering the shipwreck (Figure 2).…”

A combined particle filter and deterministic approach for underwater object localization using markers

“…Offshore gas and oil industry would also profit from autonomous manipulation systems since tasks such as valve activation, component deployment, hazardous waste disposal as well as the installation and maintenance of sub sea architectures could be performed by I-AUVs without continuous human intervention. In the DIFIS (Double Inverted Funnel for Intervention on Ship wrecks) project, for instance, I-AUVs could be used to attach mooring lines of the flexible funnel to hooks on anchors located on the sea floor in order to contain pollutants from the ship wreck and to channel low density spilt fuel to the water surface [1], [2].…”