Biodiesel standard specifications

Anon. 2007a. D 6751-06b Standard Specification for Biodiesel Fuel Blend Stock (B100) for Middle Distillate Fuels. In Annual Book of ASTM Standards (05.04). West Conshohocken PA ASTM International. 

Let s have a look at these specifications and evaluate how they relate to functionality. We can then assess how they can be related to FAME composition, and how they could be used to calculate the Lowest Cost Blend of FAME, while still complying with the requirements of the applicable Biodiesel Standard. 

Fuel density is important for blending characteristics, but also relates to emission levels, fuel consumption, and emission control systems. Similarly, the viscosity of the fuel is important. Kinematic Viscosity is included in the Biodiesel Standard because it relates directly to the injection system performance. In the Biodiesel Standards, viscosity is often set at a specific temperature point. With most fatty acid methyl esters this is never a problem, but viscosity changes at low temperature can be much more problematic. Biodiesel tends to thicken faster than fossil diesel. Specific additives might be required to deal with this. 

In the different Biodiesel Standards the specifications are linked to the fatty acid composition itself. Some characteristics may be affected by the presence of minor components, but most variation is directly linked to the FAME composition. Two questions emerge how are these relationships built, and how can we take advantage of these when making blends with the lowest possible raw material price ... 

The Biodiesel Cost Optimizer (Fig. 3.2), built as a mathematical tool, has been developed to help the biodiesel industry find a least cost formula for making FAME compositions that perform within the specifications of the applicable Biodiesel Standard. The Excel Workbook Biodiesel Cost Optimizer contains three separate sheets ... 

Standard specification for biodiesel fuel (BlOO) blend stock for distillate fuels, ASTM Standards D-6751,. ... 

Production of biodiesel with fuU conformity to international standard specification is technically difficult, especially meeting the needs of biodiesel yield of 96.5 wt.% (EN 14214)... 

ASTM International, ASTM D 6751 Standard Specification far Biodiesel Fuel Blendstock (BlOO) for Middle Distillate Fuels. ASTM International, Conshohocken, PA, USA. 

ASTM Standard specification for diesel fuel oU, biodiesel blend (B6 to B20). 2008. In Annual Book of ASTM Standards, ASTM International, West Conshohocken, Method D7467-08a. 

The specifications for biodiesel are designed to ensure that consumers will not experience operational problems from the fuel s use. ASTM and European Union have standard specifications designed for BlOO FAME used in biodiesel blending, which include GC (gas chromatographic analysis), elemental analysis, as well as physicochemical properties of the produced biodiesel [3,4]. Quality fuel will provide the consumer with improved air quality and enhanced operability. Poor quality fuel will create operability problems and increased maintenance activity. It is really necessary to look for newer approaches for the production of biodiesel particularly for variable quality feed stock employing nonedible oils or used flying oils. 

ASTM ASTM D 6751. Standard specification for biodiesel fuel blend stock (B100) for middle distUate fuels. ASTM International. West Conshohocken P... 

TABLE 2.2 Fuel Property Specifications in Biodiesel Standards... 

Induction times determined for neat fatty acid esters using the Rancimat method are also given in Tables 2.3 and 2.4. It may be noted that no unsaturated fatty ester has an induction time >3 h, which is the minimum specification in the ASTM biodiesel standard. This observation implies that antioxidant additives will almost always be necessary to attain the minimum oxidative stability specification in biodiesel standards. 

The quality of biodiesel is regulated by standards. The most important regards the content of free and bound glycerol. This cannot be modified by effective separation techniques. Therefore, the major element in design should be to obtain a composition of the mixture leaving the reaction system capable of matching the biodiesel specifications. This is difficult to achieve in view of the variety of raw materials. 

The Biodiesel Stability (BIOSTAB) project, supported by the European Commission, was initiated in 2001 to establish clear criteria and analytical methods for the monitoring biodiesel fuel stability (Various, 2003 Prankl, 2002). The resulting unified method, EN 14112 (Anon., 2003c) established a means for measuring oxidative stability utilizing the Rancimat or oxidation stability instruments. This test method was essentially developed from standards employed in the fats and oils industry to measure isothermally the induction period for oxidation of fatty derivatives. At present, both biodiesel fuel standards ASTM D 6751 (Anon., 2007a) and EN 14214 (Anon., 2003b) include an oxidative stability specification based on measurement by method EN 14112. 

Generally, test methods that should be observed are prescribed in standards such as ASTM D6751 or EN14214. However, in many cases, other test methods, usually developed by professional organizations, may be simpler, less expensive, and more suitable for process development. For example, since biodiesel is an oleochemical product, test methods developed by organizations, such as the American Oil Chemists Society (AOCS), are often well-suited, while ASTM methods were often developed specifically for petrodiesel. 

Biodiesel has been used commercially in several countries for up to 20 years, either as pure FAME or blended with petrodiesel [5]. The European and the American standards for biodiesel (EN14214 and ASTM D 6751) specify allowable limits for a large number of physical and chemical parameters. Rapeseed methyl ester (RME) meets these quality specifications, whereas FAME from other sources may have to be blended to meet the requirements [5],... 

ASTM, 2000c. D4860 Free water and particulate contamination in middle distillate fuels. In V. A. Mayer (ed.). Annual Book of ASTM Standards, Section 5, Petroleum Products and Lubricants, Vol. 05.02. Philadelphia, American Society for Testing and Materials, pp. 1113-1118. ASTM, 2000d. PS 121 Provisional specifications for biodiesel fuel (BlOO) blend stock for distillate fuels. In V. A. Mayer (ed.). Annual Book of ASTM Standards, Section 5, Petroleum Products and Lubricants, Vol. 05.04. Philadelphia, American Society for Testing and Materials,... 

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