Can Fuel Additives Help Remove Water?

phase separation

Do fuel additives have a place in fuel quality management? If so, do they work? These are both loaded questions. The short answer to both questions is “yes.” There are literally hundreds of different fuel additives on the market today ranging from octane boosters to injection cleaners. When addressing the problems associated with fuel quality management, one issue remains paramount to solving, water! The presence of water in fuel is the biggest problem. Solve this and you are well on your way to cleaner fuel.

There is always water present in fuel, the questions are how much is too much and how do we reduce it to an acceptable level. Filtration is the best way.  Coalescing and water separation technology is the most efficient way of dealing with water. However, today’s fuels are becoming more difficult to clean even with high quality filters and filtration systems.

The question then arises what do I do with highly emulsified fuel?  Can I clean it or is it unusable? There are additives that can be used to help. If fuel becomes contaminated with water and emulsifies, the water becomes suspended in the fuel and makes the fuel cloudy. It can often require a dehazer or demulsifier additive to help drop the water out of suspension. These additives help to break the bond between the water and fuel by altering the surface tension of the fuel. The water will coalesce and fall out of the fuel, making it easier to pump off and filter.

After field testing several products commonly used on the market today, we have found one product to be excellent at dehazing or demulsifing fuel – FuelDry. Take a look at the before and after samples below.

Pre and Post testing showed the water content dropped from over 2,000 ppm to under 52 ppm.  The water dropped out of the fuel and was pumped off. If you are looking for a way to help remove water or help maintain the fuel and keep it from emulsifing, email me at for help.  Even with great filtration, sometimes additives help to reduce costs by limiting downtime and helping filtration work better.

Coalescing and Water Separation


The image above shows the progression of the product stream through a coalescer media. The emulsion is broken apart, filtering the solids, then forcing the minute water particles to coalesce (to consolidate or join up) into larger droplets. Gravity pulls the larger droplets to the bottom of the filter housing allowing it to be drained off during filtration. This is the first of two phases.

The second phase involves separation. A Teflon coated water separation filter is used to repel any fine droplets of water that happen to pass through the coalescer. This second stage acts as a secondary back-up forcing the water out of the product flow – not allowing it to pass through with the fuel. It works because Teflon is hydrophobic (literally, fear of water). The water repels off of the coated separator and falls down to the bottom of the filter housing.


Coalescer filters are designed to filter solids and separate two immiscible liquids (liquids that do not form a homogenous mixture – do not mix well). In this case, separating water from fuel. Dixon coalescing filters are made of several filtration layers designed to remove dirt particles prior to coalescence, thereby increasing filter life. Inner and outer layers are made of fiberglass impregnated with phenolic resin for added strength and bonding. Situated between these layers is a coalescing layer made of borosilicate microglass. Coalescer filters are commonly used in two stages along with a water separator to remove free and emulsified water from fuel and various types of oil.


In order to prevent carryover of small water particles pushed through during coalescence, a second filtration stage is used to ensure water removal. The separator is a cartridge placed between the coalescer and the outlet. The screen on the separator is a hydrophobic Teflon coated woven synthetic material which can be cleaned periodically.

Dixon’s new filtration products include coalescing and water separation.  Give us a all at 1-800-874-8976 or email at  You can also check out our online store to order filtration suppliers or find out more.