Fuel suppliers have issued guidance for farmers, landowner and contractors who say biodiesel is causing low fuel pressure and blocking filters in tractors.

Some farmers have suggested the problems are related to an increase in the Fatty Acid Methyl Ester (Fame) content of diesel fuel, which influences its performance.

Since FAME is a powerful solvent and is hygroscopic (attracts and holds on to water) it can cause the following problems:

• Material incompatibility – Rubbers, plastics, and surface coatings will degrade when they are in contact with FAME.
• Clogged Filters – The residual deposits can cause the water particulate filters in the tank to get clogged.
• Water Contamination – Owing to the hygroscopic nature of FAME, it is more likely to hold on to water, which can cause growth of microbes / bacteria / bugs in the fuel.
• Degradation of Fuel – Oxidation and hydrolysis can cause the gradual degradation of fuel which can damage the machinery.
• Cold flow premature waxing and precipitation problems

How to get prepared?

Here are a few best practices to minimise the harmful effects of FAME (Biodiesel):

• Keep the tank clean – Make sure that your tank is professionally cleaned each time you take delivery of FAME (Biodiesel). It is important to remove water, solid deposits or mould growth before filling the tank with FAME (Biodiesel). If you are not able to clean the tank professionally, make sure that you thoroughly check the condition of your tank and fix any issues immediately.
• Check tank for bacteria – Since there is an increased risk of bacterial growth, it is important to do regular tank checks to ensure that there is no growth of bacteria in the tank. If there is a bacterial growth, it can be solved either by emptying and cleaning the tanks. You can even use additives and filters to prevent the growth of bacteria in the long term.
• Check tank for degradation – Make sure you check the tank regularly for any degradation in structure, material of the tank or any surface coatings used.
• Check for cracks and leaks – This is particularly relevant for older fuel storage tanks. Check the tank for any signs of leakage or damage and get it fixed.
• Check the particulate and water filters – There is an increased possibility that the addition of FAME will cause premature blocking of filters from time to time on dispensing tanks especially during the winter. Therefore, it is good practice to regularly change any filters.
• Check all components – Make sure that the pipework, seals, pumps and other components are checked regularly. And, if there are any leaks, get it fixed immediately.
• Prevent water ingress – Water is the biggest threat to FAME (Biodiesel) as it is hygroscopic. Make sure your tank is protected against water ingress caused by rain. So, water needs to be drained off regularly. Once water is in the fuel, it can cause corrosion of equipment and allow growth of bacteria. You can even use a water identifying paste to check if there is water content in the fuel.
• Ensure there is no moisture – Make sure your tank is brimful ensuring that there is very little air in the tank which can potentially cause moisture. Ensure that the bottom of the tank is drained of water. It’s a good practice to install appropriate breathers to keep ambient humidity out or arrange for a steady stream of dry air to be fed across the space on top of the tank.
• Avoid storage of FAME (Biodiesel) for long periods – Ideally, FAME (Biodiesel) should not be stored for more than 6 months as it has limited shelf life.
• Use of additives – You can use additives to bring your fuel up to performance specifications. Its best to get a trained professional to do this for you.
• Buy fuel from a reputed distributor – It is always good practice to purchase fuel from a reputed distributor who is certified to meet all local standards.

FRAM Farmers have identified this as an industry wide problem. They have identified that the problems seem to be worse in East Anglia and Scotland. 

At the moment industry bodies are lobbying Oil Companies to try and resolve these problems on behalf of farmers.