0
Ratings
0
Favorited
89
Views
1
Files
0
Shares
0
Downloads
0
Related
|
|
Author(s):Eric Reeves
Number Of Pages:19
Paper Abstract:Until recently, serious interest in the problem of ballast water and exotic organisms was largely limited to Canada, United States, and Australia. (Australia is in a sense the salt water analogue to the Great Lakes region, because the relatively isolated coastal salt waters of Australia have a unique ecosystem which has been severely affected by invasions.) However, the rest of the world is now beginning to realize that infections by ballast water are a more general problem and the United States Congress has now enacted legislation which would apply the current Great Lakes regime to all ports of the United States, and there are limited measures for control being instituted in New Zealand, Israel, Chile, the United Kingdom, Germany, Sweden, and Japan.
At this time, the only methods of ballast water management generally in use are exchange and retention. However, there are significant limitations on the effectiveness and the safety of exchange in ballast tanks as currently designed on most vessels. Retention imposes a severe economic cost in most cases. The two logical alternatives are to either alter the current designs of the tanks and piping systems to allow more effective and safe exchange or to treat the water in some fashion, whether ashore, in a specialized vessel, or on the ballasting ship. Most of the attention has focused on some form of treatment aboard the ballasting ship. The many conceivable technologies for treatment aboard ship have in turn sometimes been divided into two general categories, “physical measures” such as filtration, ultraviolet sterilization, heat, and acoustics on one hand, and “chemical measures” or biocides such as chlorine, hydrogen peroxide, sodium metabisulphite, copper and silver ions, ozone, glutaraldehyde-based chemicals or other nonoxidizing biocides, and tank coatings on the other hand.
|
|
|
|
|
|
|
|
|
|
