> Manufacturers Common Position Statement

Fatty Acid Methyl Ester Fuels
As a Replacement or Extender for Diesel Fuels
Diesel Fuel Injection Equipment Manufacturers
Common Position Statement 2007

Please note that this statement supersedes all previous joint statements

Background:

Diesel fuel injection equipment (FIE) manufacturers fully support the development of alternative sources of fuel for compression ignition engines. In Europe and in the United States of America, as well as in other countries, fuel resources such as rapeseed methyl ester (RME) and soybean methyl ester (SME), collectively known as fatty acid methyl esters (FAME), are being used as alternatives and extenders for mineral oil derived fuels. Furthermore, the EU Biofuels Directive 2003/30/EC requires member states to ensure that a minimum proportion of biofuels or other renewable fuels are placed on the market.

 

The FIE manufacturers are aware of issues particular to FAME fuels, and have been active in the generation of standards for these fuels. At the time of the first common position statement in 2000 there existed national standards for vegetable oil methyl esters (VOME) in Austria, Italy, Germany and France. The European FAME standard EN14214 was ratified in 2003 and supersedes these national standards.

EN14214 provides the minimum requirements for FAME quality whether used as pure FAME or as a blend component. FAME may be currently blended in quantities of up to 5% in European diesel fuel according to the EN590 specification. In order to reduce the risk of premature failure of the fuel system FAME must conform to EN 14214.  Increasing biodiesel production capacities in the EU have enabled legislative authorities to consider increasing the maximum biodiesel blending level from 5 to 10 percent. Activities are ongoing to standardize and validate biodiesel blends with up to 10 percent biodiesel (B10) in the EU. The FIE industry considers it as essential to maintain the fuel stability level of EU-B5 (IP 20h acc. to modified EN14112) also for future B10 blends. In any case an approval of B10 requires positive validation of B10 specific issues additionally.

 

To date, experience in Europe has been mainly associated with the methyl esters of rapeseed oil. Whether or not the service experience with these fuels will apply/extend to all FAMES (like those derived from soybean, tallow and used frying oil) has yet to be determined.

 

FIE Manufacturers Concerns:

FAMEs are derived from a wide range of base stocks, resulting in a similarly wide range of finished fuel characteristics.

 

Amongst the concerns of the FIE manufacturers are the following fuel characteristics:

• free methanol - water
• free glycerine
• mono, di- and triglycerides
• free fatty acids
• total solid Impurity level
• alkali/alkaline earth metals
• oxidation stability

 

All FAMES are less stable than mineral oil derived fuels. FAMEs are readily "bio-degradable" in the event of accidental spillage or leakage, which is claimed to be a marketing advantage. On the other hand, the reduced thermal oxidative stability is of major concern to the FIE manufacturers, as the products of fuel ageing can be potentially harmful to the fuel system.

Tests have shown that fuel deterioration can take place in the fuel supply chain and in the vehicle fuel system. Fuel ageing is accelerated in the presence of heat, oxygen, water, metal ions and other impurities. The products of oxidative ageing have been shown to be, corrosive (e.g. organic acids like formic and acetic acids and acids of higher molecular weight). Polymerisation products are also formed and can drop out.

 

A detailed list of potential problems for FIE systems from FAME is presented below.

 

Blends with FAME:

A particular concern is the oxidation stability of FAME blends with sulphur-free diesel fuel (S <10 ppm), which is already available in some parts of Europe and will become more widely used step by step. The oxidation stability of blends as B5 can greatly decrease when using sulphur-free diesel or 15 ppm sulphur diesel such as introduced in U.S.A. in June 2006.

 

In some countries, introduction of unesterified biogenic fuel is examined as a blending component. FIE manufacturers do not agree to this.

 

The FIE manufacturers request their customers to support their efforts to obtain good oxidation stability for biodiesel blends worldwide.

 

Diesel Fuel Injection Equipment Manufacturers
Common Position Statement on Fatty Acid Methyl Ester (FAME)

Fuels as a Replacement or Extender for Diesel Fuels

January 2007

 

 

 

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Fuel Injection Equipment — Potential Problems with FAME,

(Non-exhaustive list)

 

 

 

Fatty Acid Methyl Ester Fuels — Joint FIE Manufacturers Statement, issued January 2007