National Shipbuilding Research Program. Document Technologies Available to Clean Brackish Waters to 50 PPT TBT Levels.

摘要

The purpose of this study is to identify practical technology that can be used by shipyards to remove tributyltin (TBT) from large volumes of water to levels below 50 parts per trillion. This study is based on: (1) a review of scientific and engineering literature, (2) a review of U.S. Patents, and (3) a survey of manufacturers and users. TBT based paints are the most popular antifouling paints used on the hulls of the global merchant fleet, and the market share of TBT is still growing despite its banning or partial banning in certain areas. Shipyards generate large volumes of TBT-laden washwater during normal drydock operations. TBT has been found to be highly toxic in marine environments with observable environmental impacts at levels of parts per trillion. In 1997, after 10 years of study, The United States Environmental Protection Agency (U.S. EPA) proposed a national saltwater aquatic life criteria for TBT of 10 parts-per-trillion (62 CFR 42554, August 7, 1997). After the appropriate comment period, the standard chosen will become the basis for state water quality standards and water discharge permits throughout the U.S.