High Seas Oil Recovery Systems Development and Testing

Abstract

ABSTRACT The nature of high seas oil spills required the development of special devices which would operate and recover oil in the rough water environment. The importance of fast response to these situations dictated certain size and weight requirements and the oil spills predicted, dicated the recovery rate capability. These specifications are outlined and a history of events leading to the development and test of prototype systems is discussed. Certain of the oil recovery techniques are mentioned. Devices carried to prototype or advanced laboratory model level are discussed Examples are: the Free Vortex, the Weir- Basin, and the Disc-Drum. Attention is given to the theory of operation of these systems. Oil tests and sea tests of these devices are discussed. The capability of these systems as a result of recent design changes and tests is covered. INTRODUCTION The increased size of oil tankers, the density of traffic on the high seas, increased offshore drilling for oil and recent incidents of oil spills have all pointed to the urgent need for oil pollution control. In the event of a massive spill on the open sea, the Coast Guard will play an important role in the control, recovery, and disposal of this oil. It is the purpose of this paper to discuss the Coast Guard's approach to the solution of the problem of recovering spilled oil from the surface of the sea. Many oil recovery techniques were studied and tested. Those most promising ideas were constructed into prototype systems scaled in size to meet the rates of recovery of oil which would combat the size spill anticipated. Two such recovery devices were constructed and tested in inland pools with oil and on the high seas in calm and rough conditions. The Disc-Drum and the Weir-Basin techniques have proven quite capable of meeting the oil recovery rates projected. One of these devices, the Disc-Drum system, has been able to withstand all the rigorous testing thus far completed. A third technique, the "Free Vortex", is still undergoing research and development. This system has recently shown considerable improvement and may yet become a very useful tool as an oil recovery device both for high seas use and inland waters. DISCUSSION A massive oil spill is one wherein millions of gallons of oil are released, possibly due to a casualty of a tanker at sea or an emission of oil to the sea from an offshore drilling rig. The classic example of the kind of spill referred to is the Santa Barbara Channel offshore oil spill which caused costly damage to beaches, wildlife, recreational marine facilities and other valuables along the shore. The primitive unprepared techniques used in an attempt to recover the oil were extremely inefficient, ineffective and very costly. It is commonly agreed that if spills could be contained and recovered and not allowed to reach the beaches it could save millions of dollars in beach cleanup and restoration costs. Oil recovery from the open water is, therefore, a highly desirable objective.