Biodiesel is one way of using veg-oil for diesel fuel. It's not for Dummies because it uses flammable, toxic chemicals to convert the veg oil to biodiesel, and the toxic waste products should be disposed responsibly, not just dumped down the drain.
The other way is to use veg-oil directly. Up to 20% VO requires little or no modifications to engines with inline IPs [see below]. Greater concentrations of VO require more complicated systems to heat the oil fuel, especially at cold start up, to prevent cylinder and piston deposits and engine damage.
Using Unmodified Vegetable Oils as a Diesel Fuel Extender -
A Literature Review
www.uidaho.edu/bae/biodiesel/raw vegetable oils_literature review.doc
By
Sam Jones and Charles L. Peterson
Graduate Research Assistant and Professor and Interim Head
Department of Biological and Agricultural Engineering
University of Idaho, Moscow, Idaho 83843
Abstract
This paper is a review of literature concerning using vegetable oils as a replacement for diesel fuel. The term vegetable oils as used in this paper refers to vegetable oils which have not been modified by transesterification or similar processes to form what is called biodiesel. The oils studied include virgin and used oils of various types including soy, rapeseed, canola, sunflower, cottonseed and similar oils. In general, raw vegetable oils can be used successfully in short term performance tests in nearly any percentage as a replacement for diesel fuel. When tested in long term tests blends above 20 percent nearly always result in engine damage or maintenance problems. Some authors report success in using vegetable oils as diesel fuel extenders in blends less than 20 percent even in long term durability studies. Degumming is suggested by one author as a way to improve use of raw oils in low level blends. It is apparent that few, if any, engine studies using low-level blends of unmodified vegetable oils, < 20%, have been conducted.
Results of engine and vehicle testing of semi-refined rapeseed oil
http://www.regional.org.au/au/gcirc/6/214.htm
Kevin P. McDonnell, Shane M. Ward & Paul B. McNulty
University College Dublin, Dept of Agricultural & Food Engineering, Earlsfort Terrace.
Dublin 2, Ireland.
ABSTRACT
The renewed interest in environmentally compatible fuels has led to the choice of rapeseed oil as the main alternative to diesel fuel in Europe. The objective of this research was to produce and test an economic and high quality non-esterified rapeseed oil suitable for use as a diesel fuel extender. This was achieved by acidified hot water degumming combined with filtration to five microns. This rapeseed oil, designated as a Semi Refined Oil (SRO), has a high viscosity in comparison with diesel. Hence SRO fuel can only be used as a diesel fuel extender, with inclusion rates of up to 25 %.
SRO proved to be a suitable diesel fuel extender, at inclusion rates up to 25 %, when used with direct injection combustion systems (viz. tractor type engines). Power output (at 540 rev/min at the power take off shaft) was reduced by c. 0.06% for every 1% increase in SRO inclusion rate, and brake specific fuel consumption (BSFC) increased by c. 0.14% per 1% increase in SRO inclusion rate (viz. a 25% SRO/diesel blend had a 1.5% decrease in power and a 3.5% increase in BSFC compared with diesel). These values are in accordance with the lower energy density of rapeseed oil fuels compared with diesel. Chemical and viscosity analysis of engine lubrication oil (after c. 170 hours per fuel tested), including metal contamination as an indicator of engine wear occurring, showed that there was no measurable effect on engine lubricating oil due to SRO inclusion in diesel oil. When SRO was used to fuel IDI engines (viz. light duty commercial vehicles), power was considerably reduced mainly due to inadequate air/fuel mixing.
KEYWORDS: Biodiesel, SRO, Injector Fouling, Engine Tests
CONCLUSION:
It was concluded that SRO can be used as a diesel fuel extender in unmodified direct injection diesel engines. The only practical difference observed in this study is that the injectors require more frequent servicing compared with diesel operation. The technology for producing SRO is relatively simple and hence offers the possibility of small, locally based production units as well as economic mass production units. Rape methyl ester [aka. biodiesel] requires major investment in industrial plant. For example, a rape methyl ester plant with a throughput of 36 000 tonnes per annum has an estimated capital cost of $18 million compared with approximately $3 million for an equivalent SRO rapeseed oil plant. Thus at road side diesel station, a 25% SRO/diesel blend would cost approximately $ 0.68/litre as compared to $0.73/litre for a 25% rape methyl ester/ diesel blend. Further work is required to determine if this cost advantage (7%) for a 25% SRO/diesel blend is sufficient to contravene any negative aspects of engine performance.