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Fill up with biodiesel, please

May 14, 2004

One day, petroleum and fuels derived from it will be exhausted. Moreover, every time we take to the road in our vehicle, the mark we leave on the natural environment is huge. Nowadays, new alternatives to fossil fuels are being developed. One of these is biodiesel, a fuel produced from vegetable oil. For a month now this biodiesel can be found in certain service stations in the Basque Country.

After producing the mixture, the fuel is delivered to the service station to be sold to customers. Currently, in the Basque Country, it is being marketed at three service stations: in Bilbao (Bizkaia), in Vitoria-Gasteiz (Araba) and in Andoain (Gipuzkoa). These service stations supply a mixture, known as Bionor Mx-15, consisting of 15 % biodiesel and 85 % gas oil, and can be used in all types of diesel engines. The Bionor company forecasts an annual production of about 30,000 tons.

Bionor Transformaci'³n is made up of AZTI, the Basque scientific research foundation, the Basque Energy Authority, plus a series of smaller companies within the sector. According to Miguel Angel Garc'­a, Director General of Bionor, one of the advantages of biodiesel is the improvement in combustion, whereby the soot or burnt material - which is what come out the exhaust pipe - is reduced by approximately 55 %. At the same time, the disagreeable smell that petrol sometimes has disappears. Biodiesel is a product that lubricates the engine and, due to its detergent power, cleans it, and so we can say that it lengthens the life of the motor and reduces maintenance costs. Another of the advantages is that the CO2 cycle is neutralised given that, on being expelled through the exhaust pipe, it is taken up by plant life which subsequently produces the oil which we use as the raw material.

From the kitchen to the treatment plant
The Rafrinor and Ecogras companies have been given the task of collecting this oil and taking it to the treatment plant where solid material and excess water are removed. The pre-treated oil is then taken to the Bionor Transformation plant at the Berantevilla in Araba. Here the oil is transformed into methyl ester, i.e. biodiesel and glycerine. This involves an automated process. After weighing the lorry on the weighbridge, the oil is stored in tanks and then piped into the centrifuges where sediments are separated. The clean oil is then passed to the drying process where humidity is removed. This product is then taken to the reactor.

In order to produce a good reaction, it is important that the proportions of oil and the reactants are exact. Moreover, according to Luis Ferreiro, Manager at Bionor, the fact that the raw material is not a consistent one has to be taken into account. The process is a well-tried one. The reaction is simple: triglycerides plus alcohol produces a mixture of methyl esters and glycerol. The reaction takes place rapidly and it is over in an hour, when finally we obtain two fractions: one organic, which is the mixture of methyl esters - the biodiesel, and an aqueous one which will be the glycerol.

Subsequently, in a decanter, the two fractions of the reaction are separated and then the biodiesel is washed and dried and taken to despatch tanks. At this point, an outside body inspects the product and takes samples of it in order to certify that it complies with the regulations. It is then distributed to the outlets.

Elhuyar Fundazioa