Tuesday, March 24, 2009

Super-tanker and the risk of oil spill at sea

23248.JPGSuper tankers have been part of oil trading since 1960s. They are responsible for delivering oil and gas from refineries or producing facilities to other ports around the world. The competition among companies and the increasing demand for oil and gas has been the driving force for the increasing size of the oil carriers.
Frequently these supertankers besides having to cross large oceans such as the Pacific and the Atlantic, they have to pass by narrow yet busy straits and ports. The availability of modern navigational equipment does not guarantee that the supertankers will be free from any risk of collision with other smaller ships or boats. It is the ships' crews who have to safely guard their ships to the unloading ports. Last year, there was a tanker accident in South Korea. Oil spill from this tanker caused huge environmental damage to the coral reef, the sea, the beach as well as the fisherman villages near the area of the accident. Early this year, a cargo vessel loaded with Portland cements, and full with fuel oil in its tanks, collided with a tug boat in Jakarta bay of Indonesia. The vessel sank and spill fuel oil into the sea. Some crews lost their lives. While beach clean up can be done immediately, the destruction in the coral reef environment takes tens or even hundreds of years to recover.
Naval architects, when designing, oil tanker are guided with rules from classification societies, marpol and state regulations. They usually design tankers that have several sections or cargo holds. Collision bulkhead is also drawn at the forward end of the ship. In addition, they also provide double bottom to ensure that the tankers are still safe in case of experiencing grounding. Double bottom, collision bulkhead and double hull are not fully safe in protecting the supertankers during incidents of collision or grounding. When a supertanker experiences severe damage on its collision bulkhead, cofferdam, and double bottom, it will definitely spill oil into the sea.
Another way that we can do to reduce the negative impact of oil spill at sea is to limit the size of supertanker. It is not wise to just follow the request of ship owner by designing 500,000 tons supertanker. Size restriction is needed to ensure that the tankers that we design will not cause massive pollution in busy ports or straights. 
by Charles Roring in Manokwari of West Papua - Indonesia