Yacht barnacle inhibitor system

Abstract

A defouling system for pleasure yachts and the like. An oxygen-depleting gas is bubbled into the water in close proximity to the hull. Various barriers in the water can be positioned to reduce diffusion of oxygen to the hull surface.

Description

CROSS-REFERENCE TO OTHER APPLICATION [0001] This application claims priority from 60 / 515,203 filed Oct. 28, 2003, which is hereby incorporated by reference.BACKGROUND AND SUMMARY OF THE INVENTION [0002] The present invention relates to systems and methods for controlling fouling, i.e. the growth of aquatic fauna (such as barnacles) on the wetted surfaces of ships and boats. [0003] Background: Barnacles and Fouling [0004] Barnacles, mussels, and algae have evolved to thrive underwater on the surfaces of rocks and in crevices. When these marine organisms grow on the hulls of marine vessels, the result is a significant increase in the surface roughness of the hulls known as fouling. Fouling creates drag on the vessels that reduces maneuverability and speed per unit of fuel used. Fouling also increases overall fuel costs and reduces operational time at sea during dry dock maintenance. [0005] The traditional remedy has been a regular visit to the dry dock where barnacles and other organi...

AI Technical Summary

Benefits of technology

[0004] Barnacles, mussels, and algae have evolved to thrive underwater on the surfaces of rocks and in crevices. When these marine organisms grow on the hulls of marine vessels, the result is a significant increase in the surface roughness of the hulls known as fouling. Fouling creates drag on the vessels that reduces maneuverability and speed per unit of fuel used. Fouling also increases overall fuel costs and reduces operational time at sea during dry dock maintenance.

[0010] Fouling is not limited to macroscopic animals; fouling by bacteria can also be a problem. Bacterial fouling can accelerate corrosion, leading to pitting and even failure of metal alloy welds.

[0017] It has previously been discovered that oxygen depletion using bubbled nitrogen can slow the growth of bilge fauna. The disclosed embodiments apply this mechanism to the slightly less confined environment, namely the water which surrounds a boat in its slip.

[0018] In various embodiments, moving elements can be used to reduce wave-assisted diffusion of oxygenated water into the slip and / or to the hull surface.

[0019] The disclosed innovations, in various embodiments, provide one or more of at least the following advantages:

Problems solved by technology

When these marine organisms grow on the hulls of marine vessels, the result is a significant increase in the surface roughness of the hulls known as fouling.

Fouling creates drag on the vessels that reduces maneuverability and speed per unit of fuel used.

Fouling also increases overall fuel costs and reduces operational time at sea during dry dock maintenance.

The downside to TBT is that in waters contaminated with the antifouling agent, whelks were starting to show sex-changing disorders, and oysters developed abnormally thick shells.

Although these mixtures work well in the short term, the best formulations only last up to three years and do not match the five-year lifetime of the self-polishing TBT coating.

Therefore, there is fear that they too could cause environmental problems.

Some copper-based antifouling paints also give off toxic fumes during application.

However, none have yet been shown to be as long-lasting and effective as traditional metal-ion compounds.

Fouling is not limited to macroscopic animals; fouling by bacteria can also be a problem.

Bacterial fouling can accelerate corrosion, leading to pitting and even failure of metal alloy welds.

However, the functional requirements of ship and boat hulls are quite different.

When the vessel is underway, the flow of water can cause erosion of the antifouling paint.

It has previously been discovered that oxygen depletion using bubbled nitrogen can slow the growth of bilge fauna.

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