The accumulation of water in the bottom of fuel storage tanks and fuel handling systems is a common problem throughout the fuel industry. Condensate water and process water, in combination with the fuel hydrocarbon, can serve as a medium to support the growth of various microorganisms.
Some of these microorganisms are anaerobic and have the ability to live in low oxygen or oxygen-free environments, such as the bottom of a fuel storage tank or a low point in a fuel pipeline where water settles. Anaerobic bacteria, including sulfate reducing bacteria (SRB), and acid producing bacteria can be present in this type of environment. Compounds such as hydrogen sulfide and low molecular weight organic acids produced by these organisms can corrode iron and copper and will affect fuel odor and color.
Over time, large microbial colonies, or plaques, can develop on the bottom and sidewalls of fuel storage tanks. Microbiologically influenced corrosion (MIC) can develop below these plaques and lead to under-deposit corrosion, pitting and tank wall perforation producing tank leaks.
Nalco Champion biocides are broad spectrum in scope, attenuating and killing a wide range of microorganisms. Both fuel-soluble and water-soluble biocides are available. These biocides are registered with the U.S. Environmental Protection Agency for use in gasoline, diesel fuel, heating oil and residual fuels.