Micro Bacterial Growth in Diesel Fuel
The use of bio products in modern diesel fuels has introduced a problem in fuel storage.
This is not necessarily new news, but it continues to challenge some of our clients and so an explanation of the problem seems to be appropriate.
Water has always been the enemy of mineral fuels, but generally any water would eventually fall out of suspension and accumulate at the bottom of the tank where it could be safely and effectively drawn off. Modern fuels now comprise of a mixture of mineral and bio matter; it is the introduction of the bio component that is presenting some difficulties. Bio products are hygroscopic, meaning that they readily absorb water.
There are several microbes that can live in water but feed off the hydrocarbons in mineral fuels. As explained above, water would traditionally fall to the bottom of the tank leaving a small interface between the free water and mineral fuel where microbes could live and feed. Whilst not ideal this was generally manageable.
The introduction of bio matter in mineral fuel means that water is now more readily miscible with the mineral fuel by way of the hygroscopic nature of the bio products. The result is that microbes can now more readily exist within bulk fuel storage.
Microbes present multiple issues to the fuel in storage as follows:
• Microbial colonisation presents itself as a jelly like mass that can block filters in both the fuel dispensing equipment and the vehicle’s engine.
• Microbes excrete waste that can build up in the bottom of the tank and quickly deteriorate the quality of the fuel as well as affect the inner skin of the fuel storage tank.
• The presence of microbes in fuel storage can affect the quality of the fuel and impact the chemical specification.
• Microbial contamination can result in uneconomical and poor vehicle running and can damage the vehicle injector system.
The problem is not as widespread as one might expect. When bio mass was first introduced into mineral fuels it was predicted that contamination would become a significant and ongoing issue. Certainly, there is evidence that it is an ongoing issue, but it is far less significant than was first expected. What is prominent however is the random way in which contamination problems present themselves.
As with everything prevention is better; and in this case far cheaper, than cure. We therefore recommend the following steps:
• Use a reputable fuel supplier. Never use cheap fuel that might have come off the back of a lorry.
• Use fuel quickly, we recommend that fuel is always used within 1 to 2 months of receipt, there is much less chance of contamination affecting fuel that is stored for a shorter time.
• Store fuel in a modern totally enclosed fuel storage tank.
• Try to run a tank to a reasonably low level before accepting a new load of fuel.
• Test fuel for contamination on an annual basis and more regularly if problems are suspected.
• React to a suspected contamination problem promptly.
There are many different solutions to the problem of fuel contamination available on the market, however we believe that the only absolutely effective means of eradicating a contamination problem; once it exists, is to empty and manually clean the interior of the tank and associated pipework. The attached before and after photos of a tank clean are evidence of this.
At Cameron Forecourt, we offer the following services:
• Provide advice regarding the safe storage and use of fuel.
• Spot or regular fuel quality testing to indicate the prevalence of microbial growth in fuel storage.
• Filter inspection, cleaning and replacement.
• Fuel storage tank cleaning.
• Fuel polishing.
If you would like to discuss your fuel storage issues, please do not hesitate to contact us.