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TOMORROW’S FUELS
Which will be the fuels to means and length term? Masterful OCU-Compra 312, February-2007 In the graph
the world-wide petroleum reserves can be seen entered at the end of year 2005? The data of the table and other many related to the production, export and the economy in general of petroleum and derived can be consult in the work " A economía do petróleo se un transporte insostentable" of Xoan Ramon Doldán Garci'a, published by INEGA (2005). These reserves will be exhausted inexorably in approximately 100 years or before, according to advance the incorporation from new the most developed countries to the material development, reason why it is necessary to plan the transition to the substitution of some energies. Next the different fuel possibilities are transformed specially for all type of motors and for the automotion. MOTORS OF DIESEL CYCLE Biodiesel § Origin: esterification of fats or vegetal oils (colza, etc.) § Characteristic: similar to the gasohol, although something more viscous and of minor to be able power. Synthetic gasohol § is obtained by gas conversion of synthesis (carbon hydrogen and monoxide) in liquid fuel; the synthesis gas, as well, takes place from natural gas, petrochemical coal, biomass or derivatives (tar, bitumens, coke). § Is better than the classic gasohol because it does not have sulfur, being able to mix itself with first in lubricants for injection motors. Gasohol § Is the heavy fraction of the distillation of petroleum. § By its high density, produces a 10% more of energy, to equal volume, that the gasoline. Traditionally the gasohol motors were more lasting than those of gasoline; nevertheless, it is not clear that the present motors of gasohol injection maintain this characteristic with respect to those of gasoline. Pure vegetal oil § is vegetal oils without chemical treatment. § is more viscous than the gasohol and biodiesel, reason why important adaptations in the motors, sometimes too complicated need for the present motors of inyeccción. Dimetil ether (DME) § is obtained from the natural gas, of the coal, remainders and wood. § Is a gas liquefied to 10 atmospheres, that can be injected directly the cylinders of the motors diesel, although to being the less viscous it produces a greater wearing down of the injection systems besides to need the double volume that the one of gasohol to produce a certain amount of energy. MOTORS OF OTTO CYCLE Gasoline § Is "a slight" fraction of the distillation of petroleum. § Permits the addition of substances to improve the engine efficiency. Ethanol § is obtained fermenting sugar of cane or beet, or starch. § Can be used
pure or mixed with gasoline (in The ethanol produces a 30% of energy less than the gasoline, causing in addition greater corrosion than this one in the motor. Metanol § is made from the natural gas. § Is similar to the ethanol but more corrosive toxic and, reason why its use is minor than this one. Natural gas § Proceed directly from natural deposits. § Its precise
use of a great compression up to 200 atmospheres, to liquefy themselves and
to cool off to Hydrogen § is obtained from fossil fuels, of the natural gas and by electrolysis of the water. § In the
combustion only produces water, avoiding therefore the gas discharges with
effect conservatory. It has a serious problem when having to be used to an
enormous pressure and temperatures of Liquefied petroleum gas (LPG) § is obtained from petroleum like by-product of the extraction of hydrocarbons. § This gas is
liquid to low pressure (8 atmospheres) to room temperature. The vehicles that
use it can also use gasoline, which facilitates its use. A problem is the
great volume that needs the tank gas. In |