As a result of testing, adaptations were made to AMPOL’s Oil Stop Bottom Oil Recovery System
(OSBORS). The OSBORS submerged oil recovery system
is a specialized package of equipment designed to remove oil that has settled on the sea floor. The heart of the system is the Tornado Motion Technologies (TMT) SUBDREDGE. The SUBDREDGE is a remote controlled, track driven vehicle that is equipped with TMT’s EDDY Pump.
OHMSETT tests included placing an array of trays on the bottom of the OHMSETT tank, 11 feet beneath the surface. Each tray was loaded with sand, obstacles including cinder blocks and stacks of flagstone; and varying quantities and viscosities of one of four grades of heavy oils ranging in centipoises from 25,000 to 437,000. The oils were deposited into the trays in various and non-uniform patterns to simulate real conditions.
On one of the trays containing approximately 200 gallons of oil, at least 90% of the oil was removed within six minutes. Other test parameters included displaying the ability to remove any free floating oil and “polish” the recovered water to an extent that it could be discharged on-site.
During the oil recovery operations, background samples were taken in to a work area to measure for re-dispersal of oil in the water and for turbidity from the operations. Analysis of these samples showed near zero turbidity and only a minute trace of oil in the surrounding water.
OSBORS’ ability to effectively remove sunken oil in the OHMSETT tests proved the system as a viable method for sunken oil recovery.