Biodiesel in Gas Oil set to block filters
Changes to the supply of Gas Oil which come into being in October could cause major problems if end users are not aware of the steps they must take in advance.
New European Directives for Renewable Energy and Fuel Quality will require changes to the composition of Gas Oil in January 2011. Gas Oil intended for use in non-road mobile machinery will have to have a sulphur content of 10ppm or less and contain up to 7% by volume of biodiesel. This new fuel will become available from late October 2010.
Because of limitations in the production and supply structure in the UK, only one type of Gas Oil may be widely available and this will inevitably be the non-road mobile machinery grade with a significant Biodiesel content.
Potential Problems
Biodiesel is a powerful solvent, with good detergency properties, it will take up water from the surroundings; problems that may arise caused by the presence of Biodiesel in Gas Oil include:
- Material incompatibility – many common rubbers, plastics and surface coatings will degrade from contact with biodiesel
- Residual deposit flushing, causing clogged filters, etc.
- Water uptake, with enhanced potential for mould growth, producing solid matter and acids
- Fuel stability – Biodiesel can degrade over time by oxidation and hydrolysis
- Cold flow, waxing and precipitation problems
- Burner and component tolerance of Biodiesel &/or its degradation products
President of ICOM Energy Association, Barry Webster commented, “The strong detergency, solvent and hygroscopic properties of Biodiesel, compared with those of purely hydrocarbon fuels, will require consumers to take preparatory action to avoid encountering problems with the systems connected to their fuel supplies. Now is the time to contact your heating, hot water or steam maintenance company to be prepared for the changes”.
Preparation
An initial check on tank condition and suitability for Biodiesel-containing fuel should be carried out, this should include the material(s) of construction, age, condition and appearance, damaged areas, surface coating(s), etc and any obvious deficiencies should be remedied. The tank should be cleaned effectively internally and water & solid deposits or mould growth removed as efficiently as possible (this may require a specialised tank cleaning service). The materials used for pipes, tubes, seals, etc. should be investigated for Biodiesel compatibility and, if necessary, replaced with a suitable Biodiesel-resistant alternative; the security of joints in the system should also be examined, ensuring that Biodiesel-compatible sealing materials and compounds have been used. Check the material & condition of all filters and replace if necessary (this will be an ongoing requirement as Biodiesel-containing fuel is introduced to the system). Ensure that pump seals are made from Biodiesel-resistant material (preferably a fluoroelastomer).
Housekeeping
The routine checks & actions set out in the Oil Care Campaign booklet, “Get to know your oil tank” will be required more frequently for Biodiesel-containing fuel due to its strong detergency, solvent and hygroscopic properties compared with those of purely hydrocarbon fuels. Tanks should be frequently examined for signs of degradation in structure, material or coatings and for any other apparent weaknesses. Regular checks with prompt and appropriate removal and remedial action must be undertaken for any water, dirt, mould growth, etc. present in the tank. Filters should be examined and, if necessary, changed, especially following the first deliveries of Biodiesel-containing fuel. Pipework, seals, pumps and other components must be checked frequently for signs of actual, or potential, oil leaks and remedial work undertaken immediately. Burner components should be examined regularly for signs of degradation or deposit formation and remedial action initiated, if necessary. For fuel stability reasons, it is recommended that biodiesel fuel is used within 6 months of delivery.
Additional Information:
Equipment manufacturers should ensure that their service engineers and agents are made aware of the forthcoming changes in order to assess any likely issues and make any necessary updates to their systems prior to class D gas oil with a percentage of Biodiesel being introduced.
For further technical information relating to the above, contact;
ICOM Energy Association
ICOM Energy Association represents the interests of the Commercial and Industrial heating sectors; Boiler, Direct Fired Water, Warm Air, Radiant and Steam Raising Plant Manufacturers within the UK, Europe and Internationally. With over 95% of UK commercial boiler manufacturers’ sales through members, ICOM is well placed to inform the industry on key issues.
