Where Does Contamination Come From?
Fuel contamination comes from many sources including product aging, the environment, microbial infection, transportation and fuel system deficiencies. The image above showing the fuel supply chain from refining to end user demonstrates many places where contamination is likely to occur.
At every point in the transportation of fuel contamination is a concern, compounded by the growing demand for cleaner fuels. Once fuel is refined, it often goes into temporary storage prior to being conveyed to a terminal. Delivery might include pipeline, ship, barge, tanker or rail car before arriving at terminal storage. Fuels may be allowed to settle prior to being shipped to its next destination. Settling is important as it permits contaminants to fall out and be pumped off. However, if settling time is not provided contaminants are likely to be transferred to the next location. Tankers transfer fuels from terminals to intermediate storage or end users. This might include additional storage or directly into equipment.
Many of the components of a fuel distribution center are made up of low to mild carbon steel. Tanks, pipes and pumps are very susceptible to corrosion. Rust and metal particulates are often carried downstream to the end user. Water always presents a problem. Throughout the distribution system water can be transferred along with fuel. Even pipeline cleaning, called pigging can attribute to higher contamination levels. Even when filtration is a part of the distribution chain, it may not be adequate.
Of the contamination studies, most agree that particulate and water contamination serve to be ongoing challenges. Biofuels tend to test dirtier than non-biofuel samples. On average, a tank that receives 8,000 gallons of fuel a week can gain as much as 35 pounds of particulate contamination per year. This does not include the potential for water contamination. Much of the filtering done through dispensers – especially retail – proves to be inadequate for providing fuel that meets today’s engine cleanliness requirements.
For more information check out Dixon’s CleanFuel website or call us at 1-800-874-8976.