Tank Cleaning vs. Fuel Polishing


Tank cleaning and fuel polishing are two different processes. The question often asked, “Which one is better?” Are there any advantages to one over the other? Cost can be a determining factor as well as site downtime, if any. Tank cleaning is generally more expense. It usually requires fuel be removed and a chemical agent applied during cleaning. Once the tank cleaning process is completed, the old contaminated fuel is filtered back into the tank or new fuel is delivered. Either way the costs are higher than simply polishing fuel in place.

Opponents on either side of the cleaning and filtration industry will argue their points, but the solution is often determined by cost of service and downtime. Let’s be honest, for many tank owners cleaning versus polishing is a matter of economics. If the only economically feasible solution is to polish the fuel – then do it. It is better than leaving contaminated fuel in the tank. Ignoring the problem will only increase the cost of ownership.

However, there are times when a tank is so contaminated that it requires a tank cleaning with pressure and chemicals. Having been in the field cleaning tanks and filtering fuel for years, I have found around 20% of the tanks serviced needed tank cleaning in addition to fuel polishing.

Welcome to Dixons CleanFuel Blog

before and after sampleIn 2016, the EPA released their investigation on corrosion. In it, they say “corrosion increases servicing and equipment maintenance costs.”  For the power generation industry, this can mean increased maintenance by as much as 30%.  In the same study, they observed 83 percent of the inspected diesel fuel tanks had moderate to severe corrosion and less than 25% of the owners had any knowledge of it.

Cummins notes that the “wear of internal parts of the fuel system will decrease the life of the components and may even cause malfunctions that could result in severe damage to the other engine components.”  The picture above shows injectors pitted by corrosion caused by bad diesel fuel.  Diesel fuel is more susceptible to degradation than a decade ago.  Knowing the problems associated with diesel fuel creates a serious dilemma for every tank owner, especially those associated with backup power generation.  It is more important now than ever before to have in place a fuel quality management program.  A good program will include:

  1. Monthly bottom sampling of fuel.
  2. Quarterly fuel testing of samples.
  3. Immediate removal of any water present.
  4. Proper use of corrosion inhibitors and biocides.
  5. Yearly tank and fuel cleaning.

Without a fuel quality management program, you will have higher maintenance costs and possible liability issues because of damage caused by bad fuel.  Additionally, fuel economy can suffer by as much as 25%.  When Hurricane Sandy hit the Northeast, backup generation failed because of bad fuel.  Almost 75% of generators either failed to start or stopped shortly after startup.  Ninety percent of those that failed were due to bad fuel.  Fuel quality management is an absolute must.  Our CleanFuel blog is dedicated to bringing you the most up-to-date information on fuel mainenance issues and solutions.

“Bulk storage diesel fuel requires full filtering every six months to one year” Caterpillar