The Use Of Biodiesel
October 1, 2007 In my previous column, I discussed the basics of biodiesel and some of the quality issues surrounding this fuel. Diesel fuel is an organic material, and various types of microorganisms can live and grow at the fuel/water interface in diesel. This is why there are additives that should be used when diesel is stored for long periods of time.
Biodiesel is more highly oxygenated and has higher microbial activity, creating sludge that can plug filters. It also has a greater affinity for water than petroleum diesel. One tractor manufacturer recommends that when biodiesel is used, storage tanks should be treated with moisture dispersant. The manufacturer also recommends that a biocide be added.
Additionally, biodiesel can have a cleaning effect that loosens accumulated sediment in both storage tanks and equipment fuel tanks. The U.S. Department of Energy says “B20 is sufficiently diluted so that most (cleaning effect) problems are insignificant.”
Another tractor manufacturer says that field reports have indicated that this problem is a possibility even with B5, especially if diesel fuel storage and handling systems are old or have not been carefully maintained. If your on-farm fuel storage is due for replacement, it should be done before you shift to biodiesel.
Seals And Fuel Line Issues
Despite the fact that these problems are typically associated with older equipment, engine manufacturers have expressed concern about the effects of biodiesel on seals and fuel line hoses. Biodiesel should not be stored for over three months and the same is true for equipment that has biodiesel in its fuel system. It has been suggested that before long-term storage, operators should run the engine on pure diesel fuel for 20 to 30 minutes to flush the biodiesel out of the fuel system.
Since biodiesel has a higher cloud point than petroleum diesel, it can be a problem in colder temperatures. Recommendations include using B6 though B20 only if the outside temperature is 16°F and above and using blends over B20 only if the temperature is over 41°F. Furthermore, storage tanks should be protected from direct sunlight or frost. A number of manufacturers recommend that oil and oil filter change intervals be reduced when using biodiesel.
Using Incentives
In Europe, several countries have introduced tax incentatives to use biodiesel, which makes it cheaper than petroleum diesel and has led to growers to want to use B100 as their diesel fuel. Thus, European tractor manufacturers have been running test programs to evaluate engine performance and durability with various blends and B100.
New Holland has announced that most of its equipment equipped with mechanical fuel injection systems and a number of engines with electronic injection systems can run on B100. The B100 must meet the European standard EN14214 and the engines must use an adaptation kit and a specific maintenance program.
In addition, certain models of SisuDiesel engines used in AGCO tractors are approved for B100 fuel. The fuel must meet either the ASTM D6751 or the European EN 14214 standards. The company says that when any blend greater than B5 is used, oil, oil filter, and fuel filter change intervals should be reduced by 50%.
Since the use of biodiesel in agricultural equipment is a new development, the practices for its use are still developing. Growers should check with their equipment dealers and manufacturers for specific recommendations on the use of biodiesel in engine-powered equipment. An overall recommendation is not enough since different engines in a manufacturer’s line may have different limits on biodiesel use, due to differences such as fuel injec-tion systems.
Subscribe Today For
