Green Ships: Alternative Solutions
Alternatives to Beach Shipbreaking
Mothballing, a potential alternative to ship-breaking, is the practice of indefinitely storing a partially or fully decommissioned ship. The vessels are fully equipped for service, but are not currently needed. A negative aspect of mothballing is the expense required for ship upkeep. Likewise, the mothballing process may cause forms of environmental harm.
Improvements to the Shipbreaking Process
update information The preferred alternative to beach ship-recycling is dry docking. Dry docking is closely related to mothballing in terms of process, potential environmental harm, and high cost (up to $800,000 per vessel). Ships are dry docked in shipyards and harbors; these locations demand high quality waste management due to the particularly high risk associated with polluting water bodies in these places. The decommissioned ships can also be sunk to form artificial reefs, although this option is costly due to the need for the removal of "all environmental hazards...prior to sinking."
Toxic Sediments Relocation
Removing and relocating toxic sediment from ships offers an alternate step in the ship-wrecking process. Unfortunately, this process proves difficult on two fronts. First, finding a way to collect the sediment and a site in which to deposit it pose a challenge. A second dilemma comes with finding a way to decompose the sediment in an environmentally safe manner.
Electrochemical Removal of Tributyltin
A recently explored alternative step in ship-recycling is an electrochemical process that attempts to decompose tributyltin (TBT). Rather than risk removing the sediment and possibly contaminating the site at which it is stored, the electrochemical process seeks to eliminate the toxins right away.
In response to bans on TBT, recyclers tried scraping paint from the hulls of ships to remove the toxic TBT-based anti-fouling paint. Unfortunately, this proved to be a dangerous solution. The "washing, scraping, and repainting of boat hulls" jeopardized the health of shipyard workers. Furthermore, the paint dust that entered the air as a result of scraping could easily find its way into the marine environment.
Over time, ship manufacturers have experimented with a variety of paints as a replacement for TBT-based anti-fouling paints. Unfortunately, the biocides in alternative paints are not as effective as TBT, and using other compounds or metals can be costly. In the end, these alternative paints are more expensive, shorter-lasting, and less effective than their TBT-based predecessors. Consequently, ships painted with alternative paints need more frequent repainting and hull cleanings; fuel consumption may increase, and "trading revenue [suffers] while ships are dry-docked."
Ideally, an effective alternative paint could successfully break into the ship paint market - regardless of its initial cost. Providing precedent, TBT paints were actually very expensive when they first entered the market and became immediately popular. Their great effectiveness at keeping ship hulls devoid of organisms allowed ships to move faster, and in turn, to dump less fuel. This example offers hope that another kind of paint could experience similar success.
- Dodds, D. (2007). Breaking Up is Hard to Do: Environmental Effects of Shipwrecking and Possible Solutions Under India’s Environmental Regime. 20 Pac. McGeorge Global Bus. and Dev. L.J., 207, 208-236.
- Gipperth, L. (2009). The legal design of the international and European Union ban on tributyltin antifouling paint: Direct and indirect effects. Journal of Environmental Management, 90, S86-S95.
- Stichnothe, H., W. Calmano, E. Arevalo, A. Keller & J. Thöming. (2005). TBT-contaminated Sediments: Treatment in a Pilot Scale. Journal of Soils and Sediments, 5(1), 21-29. http://dx.doi.org/10.1065/jss2005.01.128