Korea depends heavily on imports for crude oil which is the major source of energy for the national economy and life. Since crude oil is imported through shipping, it increases risk of oil spill accidents. Initial response and response operation for preventing oil spill are important in order to minimize environmental and economic damages because oil spill accidents have tremendous effects on one's nation and people.
Representative methods for removing spilled oil in most countries are mechanical recovery with oil booms and skimmers containing and recovering oil slick on waters. However, as a multitude of factors have an influence on mechanical skimming, a series of oil spill skimmer performance tests in each country are being carried out to verify actual performance of skimmers which are used for real accidents.
Therefore, this study was conducted on evaluating performance tests of oil skimmers in Korea as more considerations should be needed.
First, the evaluation method for performance of skimmers was analyzed through the comparative analysis of domestic case (KS V 3986) and international cases (America, Norway, Canada). As a result, performance of skimmers was tested considering major factors such as wave height, type of test oil and test velocity because all factors were unable to be considered at open sea.
Second, this study focused on wave height among other environmental parameters in order to confirm whether existing performance tests of oil skimmers can prove performance of skimmers in real oil spill accidents. It was tested with different waves (0m, 0.15m, 0.25m). And researched statistical data of oceanographic conditions in Korea. As the result, the average wind speed was 9.4m/s and the wave height was 0.7m respectively
Third, two types of skimmers were tested with different wave height from 0m to 0.25m in order to confirm performance of skimmers by changing wave height. From the experimental results, the oil recovery quantity of oil skimmers decreases with higher wave height. It means when oil skimmer is used at open sea, the oil recovery quantity of skimmer with 0.7m wave height is 2.8 times less than that of 0.25m wave height.
Considering oceanographic conditions in Korea, current standards for the evaluation method is not sufficient to prove performance of oil skimmers used at open sea. Therefore, this study has suggested the new evaluation method improved by considering oceanographic conditions and wave height.
Finally, although the study has focused on effects of wave height on performance of oil skimmers, further studies will be continued to examine the effects of other parameters such as thickness of oil layer, irregular wave, test velocity and measurement time on the performance of skimmers.