Marine Tank Cleaning

Cleaning a Tank the Old Fashioned Way

• Cleaning a tank "the old-fashioned way" involves getting down into the tank, scrubbing with a brush and rags, then using a pump--or a wet/dry vacuum, if you're working on a smaller tank--and removing any sludge, dirt, or water from cleaning, then disposing of the dirty rags and the water in an approved shore facility.

  The approved shore facility is an essential, no matter what kind of tank cleaning you're engaging in. Fines under the Clean Water Act can range up to $50,000 per occurrence, meaning that the approved shore facility will be your best friend during the tank cleaning effort.

The Problems of Confined Space

• "Confined space" are two words that say a lot, including the fact that you will be in a potentially claustrophobic situation, which is a hazard.

  They also mean that you must let someone know where you are, have a watchman standing guard over you in case you pass out from some noxious fume, and that you have to be tied to a safety line, so (a) you can find your way out, (b) communicate with your watchman by pulling on the rope, if necessary, and (c) be hauled out by your safety line if you pass out.

Commercial Cleaners as an Alternative

• You can clean your tanks yourself, or you can hire it out. Most marinas and nearly all shipyards will have someone who has the equipment and the certifications required by OSHA and the other federal safety watchdogs to enter and clean your tanks.

  A word on those certifications: if they look bogus, they probably are. Every organization certifies its own people for confined space entry, according to their corporate standards. While there are training courses, some offered by reputable organizations, there is no uniform system for issuing credentials. The Federal government has only specified one type of cleaning credential, mentioned below.

  The only problem with commercial cleaners is that, if the job is small enough, you can probably do it yourself. The biggest value of commercial cleaners is that they warranty their work.

The Basics of Tank Cleaning

• Be certain that no explosive or combustible fumes exist in the tank, either by having the tank evaluated by a marine chemist or by using a flame safety lamp and following the directions for its use to the letter.

  After the tank is evaluated as being gas-free, start by scrubbing the overhead of the tank. Work your way down the sides, pushing sludge, loose paint and gunk in front of your brush or scrub pad. When you get to the bottom, you'll need a strong pump to suck the sludge out of the bottom and pump it up to the deck receptacle or to the approved shore facility. You may even have to stage pumps every 10 or 15 feet if the sludge is thick enough.

  Crude oil is not removed the same way. There is special training and a federal certification required for cleaning tanks that have carried crude oil and it usually only appears as a special endorsement on the license to a U.S. Merchant Marine Officer.

The Butterworth Machine

• The Butterworth Machine is the standard for self-contained tank cleaning in the marine industry. Built by Butterworth Systems, it works like the shower cleaning systems in home bathrooms. Turn the system on, and a sprayer head revolves in the tank, spraying a cleaner or a stabilizer at high pressure, to clean product from the walls. Pumps are then used to "vacuum up" the product washed down from the tank walls.