Energy

Biodiesel

Recycled vegetal oils, animal fats and kitchen fats can be transformed into biodiesel by using a series of technologies in order to activate those chemical reactions, at low temperatures, that lead to the formation of compounds called esters. Esters can be liquid or solid; they are soluble in organic solvents and have a pleasant smell. Then they are transformed into biodiesel and glycerine. Glycerine is a secondary product that can be used for the production of hand creams, toothpaste and lubricants. Biodiesel can be directly used, since it does not require any type of intervention on the systems that apply it (motors and burners). It is used for motor propulsion (diesel engines) both as pure and mixed with the common gas oil and for heating. The use of biodiesel reduces the energy dependence on fossil fuels, the greenhouse gases emissions and health risks due to air pollution. It is not toxic and it is biodegradable within 30 days. Diesel mixed with biodiesel has a triple biodegradability. Biodiesel contains traces of sulphur, that are in line with the new parameters established by EPA (Environmental Protection Agency) and that will be applied from the year 2006. It is safe to be handled and transported: it can be stored in the same tanks as the diesel and pumped with the same equipment, except when it is cold (it is necessary to use tank heaters or shakers). It can be completely mixed with diesel and for this reason it is a very flexible additive. Biodiesel, since it is an oxygenated product, helps to complete combustion. The reduction of polluting emissions is proportionate to its concentration in mixtures. One of biodiesel disadvantages is the emission of NOX: studies are being carried out to mitigate this problem. The performance of engines that use pure biodiesel, however, are 8-15% lower than traditional diesel, due to the different energy contents. In order to solve the above-mentioned problems, a 20% mixture of biesel and biodiesel is used. A mixture of biodiesel, ethanol (up to 15% in volume) and an additive (to help the two substances mix) is called e-diesel. The mixture is prepared by means of a spray-mixing, a process that does not require any particular equipment nor temperature control. E-diesel largely reduces the emission of particulates as compared to traditional diesel.