Biodiesel has come a long way since the first manufacturing plant opened in 1985. Major improvements in both manufacturing and engine design have aided its acceptance and use throughout the world. In the US today, B5 (conventional diesel fuel with 5% biodiesel) is used and legally labeled as conventional fuel. Diesel blends from B5 to B100 (100% biodiesel) are readily available. Like all other forms of fuel, biodiesel must be managed. There are notable differences between conventional diesel and biodiesel that make its management and use more difficult.
4 Negative Attributes to Biodiesel
- Biodiesel has lower energy content. Neat biodiesel (B100) s 8% lower than conventional diesel fuel. As biodiesel blends are lowered, energy content rises. So B20 would have an energy loss of around 2%. This may not sound like a lot, but it does add up. Engine efficiency goes down and costs to operate equipment goes up. Little can be done to compensate for the loss of energy.
- Biodiesel has poor low-temperature operability. Cloud Point is the temperature below which wax forms in diesel, giving the fuel a cloudy appearance and commonly referred to as gelling. The average cloud point of conventional diesel is 14°F. However, the cloud point of B100 can range from 23°F to 59°F depending on the feedstock it came from. The cloud point for blended diesel varys based on the amount of biodiesel. No matter the blend, the only way to compensate is to use a cold flow improver additive. The solution, use Hammond’s cold flow improvers to help overcome poor low-temperature operability.
- Biodiesel has poor long-term storage stability. When stored for more than a few months, it will destabilize. It oxidizes quickly, showing signs of accelerated aging exhibited by the formation of deposits, increased corrosion, clogged filters and clogged fuel injection systems. To increase the storage stability of biodiesel, use a Hammonds stability additive that contains increases storage stability and reduces the effect of oxidization.
- Biodiesel is more susceptible to microbial contamination. It is a food source for microbes, one that is easier to process than conventional hydrocarbons. Compared to regular diesel, biodiesel is more hygroscopic – it attracts water – more than nine times that of conventional diesel. What does that mean? Answer, more water will naturally be suspended in the fuel exacerbating the problems with microbial contamination. Microbes need water to grow. If water is present in the fuel system, it will be drawn into the fuel. Sampling, testing and treating biodiesel are all an imperative. Water bottoms must be removed immediately when found and Biobor JF fuel biocide should be used to alleviate microbial growth.
If you use and store biodiesel, plan to use both a stability additive with cold flow improver and a fuel biocide to effectively keep microbes from contaminating the fuel. Contact the experts at Hammonds Fuel Additives to determine the right additives for your specific needs.