Biodiesel, a substitute for conventional diesel

Reduces pollution and extends vehicle engine life

The used oil that is usually thrown down the sink at home can be recycled and turned into a completely ecological and biodegradable fuel. Although it cannot yet be found at all gas stations, this substitute for conventional diesel will be commonplace in our country in a few years. Biodiesel has several advantages over other fuels, but its main value is that it reduces pollution and extends the life of vehicle engines.

In Europe, biodiesel has been used for ten years, although in Spain it is now when it begins to be sold at gas stations as a substitute for diesel. All thanks to the recycling of waste that until now was thrown down the sink and ended up in water treatment plants. The first Spanish biodiesel plant started operating in Catalonia in 2002, and right now there are 25 gas stations that sell it in this community.
Biodiesel is made from used or virgin vegetable oils, although in Spain it is almost always made with used domestic oil. To recover this oil, there is a collection system that works with the main consumers of this product: hotels, catering companies, industrial kitchens or hospitals. «Once collected, it is taken to a waste management plant where it is recycled and cleaned. Then they bring it to the biodiesel plants”, explains Jordi Vaquer, director of Stocks del Valles, the first company of its kind to be opened in Spain.
In some cities there are experiences of home collection through the "green points", where citizens deposit their waste, including used frying oil. To guarantee its proper functioning, a greater awareness of the importance of recycling is required. In the opinion of Miguel Ángel García, general director of Bionor, a biodiesel company located in Álava, “the administration should be much more involved so that the regulations are complied with. There is a waste law that affects all companies, but currently it is not always complied with."
Once the product is treated and all the impurities and moisture it contains are removed, the used oil is sent to the plants that produce the biodiesel. After a transformation process, it becomes a methyl ester. “This fuel is made from vegetable oils. Until now, fuels were made with mineral oils, such as petroleum. Biodiesel has a similar chemical structure, the difference is that it is made with carbon chains extracted from vegetable oils”, specifies Jordi Vaquer.

Advantages of ecological fuel

This fuel is ecological because since it does not contain sulfur it contaminates much less than others, and it has been proven that in its combustion process polluting emissions are 55% lower than those of traditional diesel. Its main advantage is that it does not emit CO2, which causes the greenhouse effect. "But, in addition, it does not contain polycyclic aromatic hydrocarbons either, which are carcinogenic," explains Miguel Ángel García. "Another added value of this product is that it makes it possible to remove and recycle highly polluting waste, frying oil, which normally reaches the rivers from the drain."
For the director of Bionor, another point in his favor is that it reduces energy dependence on oil. "We have the raw material, so we can guarantee the fuel supply without depending on anyone." But it also has the advantage that its flash point is higher than that of diesel, which provides greater security in storage or in the event of an accident, since it costs more to burn.
Finally, biodiesel provides other benefits for cars, as confirmed by Jordi Vaquer. »This fuel improves engine performance because, being made with oils, it is much more lubricating than diesel and is better for vehicles. It has been proven that it extends its life and, in addition, the engine makes even less noise."
Before the scandal of dioxins in Belgian chickens broke out, the used oil was used to make animal feed, but as a result of this problem the European Union banned it. “That is why the companies that collect the oil have gone from selling it to an agricultural sector to supplying it to the fuel sector. We cannot pay a lot, so the collection service, which is now free for companies, will have small fees in a very short time”, advances the director of Bionor.

Can any car use it?

All diesel vehicles can use this fuel without making any changes to the engine, as long as it is sold mixed with diesel. In fact, at the moment no gas station sells it 100% pure. As García explains, “if it was sold unmixed, a small and simple modification would have to be made to the hoses of cars over ten years old. But it is always blended with diesel A, normally it is 15% biodiesel with 85% diesel”.
In Catalonia, the first gas stations that marketed it mixed it in a proportion of 30% biodiesel and 70% diesel, but due to the great demand they had to dilute it more and lower it to 10%. This, in Vaquer's opinion, does not mean that the fuel loses its ecological value. «It does not matter if the 6,000 tons that we produce are consumed by a single vehicle or distributed among thousands of cars in a lower dilution. What matters is that pollution is reduced, since it avoids the consumption of 6,000 tons of traditional diesel”.
Biodiesel production is currently still very small in Spain, as there are only two plants, in Catalonia and the Basque Country, which produce 6,000 and 22,000 tons respectively. But the forecast is that in the next five years a few plants will be opened, which will at least make it possible to comply with the European directives regarding renewable energies.
According to the deadlines established by this European Union regulation, by the year 2005 2% of energy consumption should come from renewable energies, including biodiesel as a substitute for diesel. By 2010 that figure rises to 12%, and in 2020 the goal is to reach 20%. The general director of Bionor acknowledges that “the possibility of substituting all oil for other energies is still very distant. For now, if we wanted to produce more biodiesel, farmers would have to grow more oilseeds to be able to have not only used oil but also virgin oil."
Countries like Germany, France, Italy or Austria have a great advantage in this matter. "Here we are just beginning," says Vaquer. In Germany, for example, there are already a thousand gas stations with pumps of this fuel. In Spain there are still few that offer it, but this is also due to reasons that have nothing to do with the low production, as explained by the Stocks del Valles plant manager. «The problem is that many gas stations are not free and are forced to buy from a single distributor, for example only from Repsol, or Petronor, etc. We cannot sell biodiesel to them, and we can only work with the free ones. So this situation makes further distribution quite difficult,” he says.
The price of biodiesel at gas stations is the same as that of traditional diesel. This fuel can also be used for heating or to produce steam, but in practice it is not profitable. «We manufacture it to be a substitute for automotive diesel because otherwise the numbers do not come out. You pay much less for diesel C for heating”, explains Miguel Ángel García. Vaquer is of the same opinion, who believes that "we can only be competitive if we manage to sell at the price of diesel".

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