Straight fuel is hydrophobic; that is, it won’t blend with water, so any water that gets into the tank usually sinks to the bottom. Ethanol is hydrophilic so water that enters the tank will be absorbed by the fuel. Ethanol 10 fuel added to a tank with water in it immediately can become a whole tank of waste as the water being absorbed puts the fuel off spec. This can become very expensive when you clients come back and want their vehicle fixed because water destroyed the fuel pump in their brand new car!
Understanding and controlling the impacts of this additive on your fuel and your tanks is important to your business.
The American Petroleum Institute* refers to three critical outcomes of water pollution in fuel ethanol mixes:
- · Phase separation
- · Micro-organisms
- · Accelerated Corrosion and Conductivity
Phase Separation
Small quantities of water can be dissolved in a gasoline-ethanol blend, but beyond a certain concentration (.5‰ @ 60 degrees F), saturation will be achieved. Any additional water beyond this point, even a small amount, will cause the ethanol to separate from the gasoline and form a separate solution with the water.
Micro Organisms
Water is needed for bacteria growth. Ethanols attraction of water creates a healthy environment for microorganisms and they are happy to take the oxygen from the water and feed on the hydro carbons in the fuel. This is what gums up your filters and causes microbial induced corrosion (MIC) in your tanks.
Accelerated Corrosion and Conductivity
Compared to gas and hydrocarbon fuels, ethanol has a high electrical conductivity and oxygen content. The properties of ethanol lends itself to the creation of electrolysis inside your tank . Ultimately this leads to metal loss in various components – Turbines and piping – that are not normally adversely affected by gasoline. Fine particles of metal will suspend in the fuel and will clog your filters. Many who see this fine suspension will assume it is bacteria and a hum bug kit may confirm that hypothesis. However, the fine particulate is metal that is being released from your equipment by electrolysis and bacteria will cling to the particulate creating the false impression that it is simply bacteria. It is an indication of a bigger problem and without galvanic protection on these gasoline tanks they and the equipment will degrade faster than originally planned for.
Maintenance is the Solution
Controlling the water in a tank is the key to living with ethanol in gasoline tanks. Sampling should be done annually in addition to daily tank monitoring. Water indicated in a tank should be removed immediately.
