Making Biodiesel

The Process

Biodiesel or FAME – fatty acid methylesters is now readily accepted as an alternative fuel for diesel engines. FAMEs are produced from renewable sources and exhibit an ecologically friendly profile of a combustion fuel. They can be blended with classic diesel fuel in any ratio and can be used in diesel engines without any necessity to modify the engine while maintaining or improving engine performance.

The key feature of the process is the transesterification of degummed vegetable oil by methanol in the presence of an alkaline catalyst in a one-step operation occurring at elevated temperature and pressure, followed by subsequent final treatment consisting of, extraction of glycerine, dry washing and final polishing. Using the process recommended by EuroFuelTech no ecologically harmful waste or wastewaters are produced.

 

Transesterification is the displacement of alcohol from an ester by another alcohol in a process similar to hydrolysis, except that an alcohol is used instead of water.

This process has been widely used to reduce the viscosity of biological fats and oils (triglycerides).

How do I use this chemistry to make biodiesel?

From our smallest processor to our largest multi processor installtions EuroFuelTech equipment follows the same principles.

  • First the oil which forms your feedstock may need pre-treating such as the removal of particulates or water using equipment such as centrifuges or oil driers
  • The oil is heated in pre-heating tanks
  • Methanol and NaOH (or KOH) are added to the methoxide mixer (liquid methylate can also be used)
  • After methoxide has been prepared and added to the processor, pre-heated oil is pumped into the processor
  • The temperature is raised and the processor operates under pressure to prevent loss of methanol vapour and allow rapid transesterification to take place in a single step
  • After the correct temperature has been reached, the processor automatically maintains it during the chemical reaction. The whole process finishes in approximately 60 minutes.
  • The mixture is purged from the processor
  • The process of separating the biodiesel and glycerol using centrifuges or settling tanks is undertaken.
    Following the removal of glycerine from the biodiesel, it is transferred to a washing station where it is passed through ion echange resins that remove dissolved contaminants
  • Methanol Recovery Units complete extraction of most of the Methanol from the Glycerine and the Biodiesel
  • Throughout the process wherever methanol is present we recommend blanketing all tanks with a source of nitrogen (preferably a nitrogen generator), this important safety feature also benefits the process due to the drying quality of nitrogen
  • In order to be sure that the biodiesel is 100% clean, it is polished, that includes filtration down to 1 micron.


The resultant biodiesel is ready to be used and, provided the specifications of ingredients have been met and the process followed correctly, it will meet the EN14214 standards.