March 2009 Vol. 236 No. 3

TechNotes

Coming Biofuel Blends Heighten Need For Fuel Tank Cleaning And Maintenance

Although there are currently no regulatory requirements around tank cleaning, it is an industry understanding that ongoing preventative maintenance of fuel tanks can help service station operators prepare for ethanol-blended products of the future.

There are many reasons to invest in periodic tank cleaning, but these reasons top most operator lists: maintain a quality product, reduce maintenance problems, gain and keep customer loyalty and satisfaction, receive long-term returns on tank system investments, reduce or eliminate phase-separation concerns while preparing for ethanol-blended fuels.

Cleaning Tanks

Many tank-cleaning experts recommend cleaning tanks via a multi-step process. The first step removes debris from the tank. Then, the fuel is passed through three cycles. Next, the product is pumped and filtered and sent through a coalesce cycle which extracts water from the product. The reclaimed product is then re-introduced back into the tank. This process can be done using onsite mobile trailers.

Alternative Fuels

Tank cleaning is especially important as service stations prepare to accept ethanol-blended products. According to Crompco, LLC, ethanol doesn’t react well when it mixes with water. Ethanol is said to absorb water, and when a water-saturated ethanol product becomes heavy and falls to the bottom of the tank, the two substances separate. Crompco says this is called phase separation. Phase separation begins with as little as ½ of 1% of water content, according to Crompco. The firm points out that equates to only 40 gallons of water in every 8,000 gallons worth of product. The result of phase separation is contamination and an unusable product.

Reclaiming Contaminated Product

Companies like Crompco and others can reclaim separated product via a specialized product polishing process. Chuck Pedano of Crompco says, “We can remove the ethanol and water and bring the product back to a usable state.”

He adds, “Through independent pre-recovery and post-recovery sampling, we provide a product lab analysis for a final determination of how the customer can use that product once it’s been polished.”

The lab analysis outlines the water content, percentage of ethanol and octane. This information is given to the customer and–based on the analysis–the station can decide how to reuse the product.

“To avoid the issues caused by dirty tanks, tank cleaning should be an integral part of every service station’s preventative maintenance program,” recommends Pedano.

Like any well-run business, tanks and tank systems must be prepared for the blended fuels. Pedano maintains that “at the moment tank cleaning is not regulated, but as we progress into an era where alternative fuels become commonplace, preventative maintenance, cleaning and testing of tanks and systems will become the rule rather than the exception.”