Characteristics and treatment of wastewater generated during underwater hull cleaning operations of U.S. Navy ships
Abstract
For the last 15 years the U.S Navy has been using an underwater diver-operated brush mechanism to clean marine fouling on ship hulls. During this operation, it has been shown that 1 to 2 mils of antifouling paint (which is 40-50 percent cuprous oxide by weight) are removed, resulting in the discharge of up to 1300 pounds of copper into the surrounding surface waters. This paper reviewed and summarized the recent studies which have been conducted relating to hull cleaning. Among other things, the studies measured dissolved copper in the wastewater ranging from 0.13 mg/L to 4.3 mg/L. These values exceeded the Environmental Protection Agency water quality criterion of 2.9 micro g/L for dissolved copper. Nevertheless, one study even concluded that hull cleaning wastewater may not be toxic to microalgae in the surface waters because the measured dissolved copper concentrations during hull cleanings were lower than the observed IC50 values for the microalgae. Calculations determined the approximate amount of waste that would be generated and the concentration of copper in the waste. From these estimates, four treatment technologies were discussed as possible alternatives for treatment of the wastewater containing antifouling paint: ion exchange, dissolved air flotation, crossflow microfiltration, and living and non-living biological treatment systems. In addition, an economic analysis was undertaken to compare three levels of treatment: off-site treatment by a commercial facility, on-site treatment to meet minimum sanitary sewer discharge limits using a dissolved air flotation system, and on-site treatment to meet minimum surface water limits using crossflow microfiltration and ion exchange.
Collections
Related items
Showing items related by title, author, creator and subject.
-
A Review of Alternatives to Injection of Petroleum Wastewater from Oil and Gas Extraction
Sly, Mary E. (Monterey California. Naval Postgraduate School, 2020-05-21);Petroleum refinery production wastewater is likely increasing the toxic contaminants in freshwater sources and contributing to freshwater scarcity despite regulatory guidelines, resulting in negative impacts to aquatic ... -
Characterization and treatability of hydroblast wastewater
Alexander, Kenneth C. (1988);At the present time, there are no effluent guidelines or treatment requirements for wastewater discharges resulting from the practice of hydroblasting, unless hydroblasting is performed in a graving dock. Little is known ... -
In-line treatment of metal contaminated storm water by charred microporous polymers
Kliem, John A. (Monterey California. Naval Postgraduate School, 1998);This paper examines the feasibility of using an in-line storm water treatment system to remove heavy metals from storm water discharges. There are a number of commercially available microporous carbons that have a demonstrated ...