• The Filtration Process
  • Why Fuel Goes Bad
  • Understanding Ethanol
  • Hazardous Material and Waste
  • Hydro-Treating
  • Chemicals
  • The Filtration Process

    Upon arrival on your site we set up our equipment as close to the tank as possible. The closer we can be to your tank the better so as to minimize the risk of accidents from excessive hoses and equipment. A suction hose is inserted through an access port at the top of your tank straight down to the bottom. We must have straight down access in order to guarantee our work.

    The semi-flexible suction hose will draw up and remove the bulk of the contaminants which settle at the bottom of your tank so it does not get “stirred up” during the filtration process. This hose helps Clean Fuels Technicians reach areas of your tank that our competitors may miss.

    Next we attach the suction hose to the filtration unit which is comprised of a water separator and a series of filters. These filters will remove any particles from 5/100 of a millimeter (5 microns) and up. To give you a better idea of how clean that is, typically when fuel comes from the refinery it has been cleaned down to 25 – 35 microns. At this point a biocide can be added to diesel fuels to instantly kill all bacteria and algae growing in your tank. The fuel is then returned to your tank under pressure to agitate any possible algae or debris clinging to the side walls of your tank. The fuel from your tank cycles through our filtration unit continuously until both the fuel and the tank test clean.

    When filtration is complete you may be offered to have a fuel stabilizer added to your diesel fuel if you and the technician decide it is necessary. You can expect to see a before and after sample of your fuel while we are on site.

    Why Fuel Goes Bad

    Your fuel is vulnerable to water contamination during transport and storage. Once you have water in the system, you are set for an invasion of microorganisms.

    All storage tanks are vented to the atmosphere. This venting process pulls in outside air which contains humidity and airborne, microscopic bacteria spores. Since water is heavier than fuel, it collects under the fuel, and forms an interface of fuel and water.

    Anaerobic (not needing air) microscopic bacteria spores attack the fuel/water interface, where they thrive and multiply. Once established, they entrench themselves in creating a thick layer of slimy deposits.

    Aerobic (needing air) bacteria and fungi also grow above the fuel surface, on the sides of tank walls, on internal pipe surfaces, and in filter housings. Left unchecked, microbial assault in these areas leads to accelerated pitting, and corrosion.

    For all the problems microorganisms can bring, confirming their presence (or absence) in your tanks is not always a simple matter. Growth at the interface is typically patchy and irregular. If the microorganisms are not growing directly under your sampling ports, they may go undetected.

    Under economic pressure to produce more high-value fuel from each gallon of crude oil, the refining industry has developed increasingly effective chemical agents and more sophisticated cracking methods to achieve higher yields of gasoline and diesel fuels. While economically desirable, the fuels you purchase are far less stable than those of even a decade ago, being far less tolerant to water and storage. The effect is a dramatic increase in the incidence of bacteria, sludge, and emulsion.

    Water dispersing additives are designed to break down the water molecules so it can be burned. These additives often create emulsion that is recognized by the water separators as fuel, but to the engine it is water and this leaves you with an a poorly functioning engine.

    Using a biocide to treat living bacteria in fuel tanks can cause greater problems than what you initially started with. Bacteria that is living will pass through your filters, where as dead bacteria treated with biocide will wax and clog your filters. The best way to handle bacteria is to treat the fuel and then have it Filter Flushed thus removing the dead bacteria.

    Understanding Ethanol

    In general Ethanol is mixed with gasoline at a rate of 10%, to help raise the octane level bringing it to 87 for regular, 89 for midgrade and 93 for high test. Ethanol bonds better with water than it does with gasoline so when water gets into your tank it breaks the gasoline/ethanol bond, creates a water/ethanol bond and settles to the bottom of your tank very slowly (a matter of a couple weeks). Obviously this lowers the octane level of your gasoline. Breaking this water/ethanol bond and removing or restructuring the water molecules will cause the ethanol to recreate the weaker bond with the gasoline. However, the water molecules will not leave your tank, current products simply disburse the water throughout the tank so that it is the same weight as the fuel. This can prove to be potentially problematic if the water is not restructured properly.

    This phase separation can begin due to as little as .5% water being introduced into your tank through condensation, deliveries or through open vents or damaged seals. When phase separation begins the gasoline will start to look opaque and is often described as looking like orange juice.

    In smaller tanks such as boats or generator tanks under 150 gallons, at this point in time, we recommend pump off and removal of the fuel and starting with a fresh tank. We can pump off the water-ethanol mix that has already settled but we cannot guarantee that additional water and ethanol will not continue to separate.

    In larger tanks, we can have large quantities of water and ethanol removed before we run our filtering process. Once we have cleaned the fuel it is important to understand that it will have lost some of it’s octane rating. The octane rating can be brought up by “splash blending” a higher octane fuel. Please check your local regulations to see if this is something you can do in your area.

    We are currently exploring new products, which may help reduce phase separation and maybe actually reverse the process!

    Hazardous Material and Waste

    Hazardous Materials (HAZMAT) are any material which, if improperly handled, could potentially cause serious harm to people, animals or the environment. Gasoline, Diesel, Kerosene, lube Oil and Jet Propulsion Fuel are all considered Combustible HAZMAT and as such, are labeled under Class 3 HAZMAT handling guidelines. The HAZMAT guidelines are strictly regulated by the Federal and State Governments, especially when transporting those materials.

    For example, because we work with and transport your HAZMAT, Clean Fuels Associates, Inc. Is required to have certain licenses and follow the HAZMAT guidelines very closely.

    Did you know that a person is only permitted to transport up to 119 gallons of Class 3 HAZMAT without having a Red Class 3 Placard on their vehicle? Did you know that a person is required to have a HAZMAT endorsed Commercial Drivers License whenever a HAZMAT placard is required for their vehicle?

    That’s right, any technician or driver who carries over 119 gallons of fuel or fuel waste must possess a HAZMAT endorsed Commercial Drivers License according to Federal Law. Additionally, there are state laws and Department of Transportation regulations which govern how and where that material or waste is contained, used or disposed of. Clean Fuels Associates prides itself on being 100% in compliance with all HAZMAT, Environmental and Safety laws and regulations, then going beyond what is required. Even our office staff, up to the VP of Operations has Hazardous Waste Operator and Emergency Response (HAZWOPER) certifications.


    The diesel fuel you buy is always changing in both chemical content and quality. Since October 1993, the refining process for diesel fuel was changed to include a process called Hydro-treating. This process significantly reduces the sulfur and aromatic content of the fuel making the product we buy far less stable than the fuel we bought a decade ago. It also can introduce potentially harmful amounts of water into the diesel fuel that may end up in users' tanks across the country.

    Since October 15, 2006, the government has required Ultra Low Diesel for *on-road use. This means the hydro-treating process has been further intensified to remove the equivalent of another 80 percent of the sulfur. This has further exacerbated an already serious water problem and resulted in fuel with reduced lubricity. The benefits of a cleaner environment are achieved but with additional costs to the diesel user as today's fuels are more susceptible to water and do not provide the traditionally high level of lubrication to critical engine components such as injectors and fuel pumps.

    Water in fuel can be in several forms: free water or heavy water is usually found at the bottom of tanks. Emulsified or suspended water gives the fuel a cloudy appearance. In addition to higher water content at the pump, additional water is formed by year round condensation. Water separators help with the heavy water but fall short of solving the problem of emulsion.

    Each time a diesel engine operates, regardless of the time the year, condensation forms. When the water reaches the diesel fuel injection system, the effects can be ruinous. The injectors depend on the diesel fuel for lubrication. Water further reduces lubricity as it washes away the thin oily film coating the injectors' Micro-Machined surfaces, causing enlargements of the spray holes, eroding the injector tips, and destruction of the spray pattern. In a precision part like a fuel injection pump, this damage can be enormously expensive and result in equipment downtime waiting for repair.

    * Does not yet apply to train locomotives, marine, or off road uses until December 1, 2010. In 2010, the sulfur concentrations allowed in diesel fuel for generators and other non-highway applications will migrate to the current on road standard for diesel fuel. This is considered ultra low sulfur diesel (ULSD) and has an allowable concentration of 15 ppm sulfur.


    Clean Fuels has tested a number of chemical additives and identified two specific chemicals that contribute significantly to fuel cleaning and purification that are particularly effective when used in combination with our filtering process. Warning: Using some chemicals without filtration has a potential for causing even more problems in your tank and equipment. Please consult fuel professionals before introducing chemicals into your tank on your own.

    The first chemical is a biocide used in diesel and heating oil that immediately kills and coagulates both types of bacteria present in your tanks. Use of the biocide immediately prior to filtration ensures that the coagulated residue is removed from the tank and not left to clog up injectors, nozzles and filters.

    The second chemical is a Fuel Stabilizer that is perfect for fuel in back up generator tanks to restore the diesel fuel to its optimum performance levels. Lubricity puts back the lubrication lost by elimination of the sulfur. This highly concentrated diesel fuel treatment provides a wide range of benefits by:

    • Cleaning injectors and improving fuel consumption
    • Reducing oxidation, controlling bacteria and dispensing water
    • Cleaning pre-combustion deposits from your fuel system and removing carbon deposits in combustion areas
    • Improving emissions and preventing the formation of harmful acid build-up
    • Extending the life of your fuel storage tanks while producing a premium grade diesel fuel
    • It improves cetin levels, help prevent rotary and piston fuel pump wear, reduce pintle scoring.
    • It exceeds ASTM and engine manufacturers most recent recommended lubricity standards for ultra low sulfur diesel when properly administered.
    • Ideal for lubricating blended fuels, and helps prevent fuel icing. Generator manufacturers have introduced new engine standards for equipment built since 2006 to allow the use of ULSD with reduced risk of damage to fuel lubricated components such as injectors and fuel pumps. Generators built prior to 2006 are AT RISK unless lubricating additives are used regularly after the introduction of ULSD.