Annex 34-1: Analysis of Biodiesel Options
Use of fatty acid methyl esters (FAME) as a substitute diesel fuel is on the rise around the world. In the US, for example, the volume of biodiesel used in transportation has grown by a factor of 6 to 7 times in four years, and in Europe the situation is similar. Such a rosy outlook for biofuels is not without technical hurdles, though. Methyl esters face some serious technical barriers, i.a. poor oxidative stability, incompatibility with some elastomers, low-temperature flow properties, and higher NOx emissions.
The transesterification process is limited in feedstocks to using oils derived from vegetable, animal, and waste fats. If we are to achieve greater impact of bio-derived fuels, we must utilize all varieties of feedstocks and produce a broader slate of fuel choices, ranging from gasoline replacements to diesel replacements. Therefore, the world’s attention is turning to concepts of more diverse manufacturing processes, and the notion of a flexible biorefinery is coming into being.
Purpose and Objective
IEA Advanced Motor Fuels Agreement (AMF) has been running Annexes on biodiesel, i.e. Annex XIII “Emission performance of selected biodiesel fuels” and Annex XXX “Bio-safety Assessment: Animal Fat in Biodiesel”. Research on advanced motor fuels, especially biofuels, is abundant in today’s changing world of energy. However, research on production potential and end-use aspects tend to be more or less separated. Alternative motor fuels are today’s reality, and thus it is important to improve links and understanding between forums focusing on production potential and usability factors of different motor fuel options.
The overall objective of this annex was to provide a better picture for the IEA-AMF of where the biodiesel industry is going in the future – how technical barriers will be overcome, what bio-derived fuels will replace significant quantities of diesel fuel, what will be the feedstocks for those fuels, and what will be the processes by which the fuels will be made. The potential of different biodiesel options will be linked to end-use aspects.
Fuels, Engines, and Emission Consulting (FEEC), USA