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A solution for your dirty bilge

Inventor claims his Bilge Water Trap reduces oils

and hydrocarbons to 50 parts per million

Inventor claims his Bilge Water Trap reduces oils

and hydrocarbons to 50 parts per million

A Connecticut boater suffered from an embarrassing problem — a dirty bilge that resulted in spilled oil — and went to work on a solution.

Robert Anderson, who owns a scientific instrument company in East Norwalk, was aboard his 50-foot vessel around Memorial Day last year when a fuel oil leak announced itself to his whole marina. People started to holler and jump up and down on the dock, Anderson says, as the bilge pump on his 1966 Hatteras sportfisherman dumped oil into the water.

“Anytime the bilge pump comes on I say a little prayer that I’m not sitting in a puddle of oil and that people are noticing,” says Anderson, adding that the boat had a dirty bilge when he got it in 1978.

The twin engines on the vessel are themselves 38 years old, he says. “After the first 10 or 15 years, engines start to drip and leak,” says Anderson. “In a car it drops on the road, but in a boat it drops in the bilge.”

Some drips and leaks are not cause for a rebuild, and using a bucket to clear the top layer of scum off the bilge water just is not feasible, he says. “There’s got to be a simple fix for this,” he remembers thinking.

So Anderson, 65, went home and designed a containment tank that he displayed at boat shows this fall.

The Bilge Water Trap removes hydrocarbons from bilge water before it’s discharged overboard. It works much like a food-service grease trap, a device with which Anderson came in contact while on kitchen patrol duty in the Army in the 1960s, he says. Grease traps use the lighter weight of oil relative to water to separate the two, a process called gravimetric separation.

The Bilge Water Trap has floating coalescing balls at the top of the tank where the bilge water enters. These plastic balls attract oil but not water, Anderson says. When the oil and water mixture brushes against them, he says, the oil wants to stay.

The oil and water separate, as the lighter oil floats at the top of the containment tank, and the water trickles to the bottom and is pumped overboard.

The trapped oil should be bled off the top of the tank into a container, such as a jar, periodically. This should be done every two weeks for a boat with a dirty bilge, or from once a month to once a season for other boats, Anderson says. Bleeding off the raw oil is the only maintenance the system needs, he says.

The boat’s bilge pump powers the process, Anderson says. The tank, which mounts to a bulkhead, just has to be fitted in series with the bilge pump and through-hull outlet, and kept at least 90 percent full at all times.

The 6-gallon Bilge Water Trap is the most popular size, Anderson says. Other sizes include 3, 9, and 12 gallons. The 6-gallon trap sells for $500 and will process 15 gallons of bilge water a day.

“I’ve had [The Bilge Water Trap] in my boat all summer and I haven’t seen one bit of oil come out of the bilge,” says Anderson. “It’s a very comforting factor to know that if there’s oil in the marina it’s not from me.”

In tests performed by an independent lab, a bilge water sample containing 50 percent oils and hydrocarbons (around 500,000 parts per million) was reduced to 50 parts per million after treatment. Anderson says the discharged bilge water is “10,000 times better for $500.”

Although Environmental Protection Agency standards limit oil discharge to 15 parts per million, Anderson says that does not concern him.

“We’re not claiming in any way that we’re compliant,” says Anderson. “We’re just claiming that it’s one hell of a lot better.” He says the product will save all sorts of plant life and wildlife.

Marketing the Bilge Water Trap at boat shows has been a challenge, Anderson says.

He compares displaying a product for dirty bilges to having a booth for people with bad breath. “All the people that came in had a ‘friend’ that had a dirty bilge,” he says.

Anderson surely can understand the embarrassment.

The Bilge Water Trap is available through Buck Scientific, East Norwalk, Conn. Phone: (203) 853-9444.