Fuel compatibility

At the present moment, almost of methanol has been produced from natural gas through steam reforming followed by synthesis from hydrogen and carbon monoxide. Methanol is a promising fuel in future, because it is easily handled as liquid fuel, compatible with the existing infrastructure of motor vehicles, and wide application for direct burning and fuels for fuel cells. Furthermore, it is widely used for bulk chemicals. 

Millions of alternative fuel compatible vehicles on the road, dominated by ethanol compatible vehicles... 

In practice, the user prefers the densest possible motor fuel that is compatible with the specifications, for it gives him the best volume NHV and highest fuel economy. It is estimated that an increase in density of 4 to 5% brings a reduction in consumption of 3 to 5%. Finally for the refiner, a margin of 50 thousandths accorded for the density of each type of gasoline, makes an acceptable compromise, while a tightening of the specification would be too constraining. 

Revised fuel system materials for methanol compatibility... 

Long-chain esters of pentaerythritol have been used as pour-point depressants for lubricant products, ranging from fuel oils or diesel fuels to the high performance lubricating oils requited for demanding outiets such as aviation, power turbines, and automobiles. These materials requite superior temperature, viscosity, and aging resistance, and must be compatible with the wide variety of metallic surfaces commonly used in the outiets (79—81). 

Climate and Environmental Factors. The biomass species selected for energy appHcations and the climate must be compatible to faciUtate operation of fuel farms. The three primary climatic parameters that have the most influence on the productivity of an iadigenous or transplanted species are iasolation, rainfall, and temperature. Natural fluctuations ia these factors remove them from human control, but the information compiled over the years ia meteorological records and from agricultural practice suppHes a valuable data bank from which to develop biomass energy appHcations. Ambient carbon dioxide concentration and the availabiHty of nutrients are also important factors ia biomass production. 

High Heat- Value Gas. High heat-value (high Btu) gas (7) has a heating value usually in excess of 33.5 MJ/m (900 Btu/fT). This is the gaseous fuel that is often referred to as substitute or synthetic natural gas (SNG), or pipeline-quaHty gas. It consists predominantiy of methane and is compatible with natural gas insofar as it may be mixed with, or substituted for, natural gas. 

The gas turbine power plant which has revolutioni2ed aviation derives basically from the steam turbine adapted to a different working fluid. The difference is cmcial with respect to fuel because steam can be generated by any heat source, whereas the gas turbine requires a fuel that efficiently produces a very hot gas stream and is also compatible with the turbine itself. The hot gas stream results from converting chemical energy in fuel directly and continuously by combustion in compressed air. It is expanded in a turbine to produce useful work in the form of jet thmst or shaft power. 

Compatibility and Corrosion. Gas turbine fuels must be compatible with the elastomeric materials and metals used in fuel systems. Elastomers are used for O-rings, seals, and hoses as well as pump parts and tank coatings. Polymers tend to swell and to improve their sealing abiUty when in contact with aromatics, but degree of swell is a function of both elastomer-type and aromatic molecular weight. Rubbers can also be attacked by peroxides that form in fuels that are not properly inhibited (see Elastomers, synthetic Rubber, natural). 

Fouling organisms attach themselves to the underwater portions of ships and have a severe impact on operating costs. They can increase fuel consumption and decrease ship speed by more than 20%. Warships are particularly concerned about the loss of speed and maneuverabiHty caused by fouling. Because fouling is controUed best by use of antifouHng paints, it is important that these paints be compatible with the system used for corrosion control and become a part of the total corrosion control strategy. 

Being acidic, fluorocarbon ionomers can tolerate carbon dioxide in the mel and air streams PEFCs, therefore, are compatible with hydrocarbon fuels. However, the platinum catalysts on the fuel and air elec trodes are extremely sensitive to carbon monoxide only a few parts per million are acceptable. Catalysts that are tolerant to carbon monoxide are being explored. Typical polarization curves for PEFCs are shown in Fig. 27-64. 

An on-line supercritical fluid chromatography-capillary gas chromatography (SFC-GC) technique has been demonstrated for the direct transfer of SFC fractions from a packed column SFC system to a GC system. This technique has been applied in the analysis of industrial samples such as aviation fuel (24). This type of coupled technique is sometimes more advantageous than the traditional LC-GC coupled technique since SFC is compatible with GC, because most supercritical fluids decompress into gases at GC conditions and are not detected by flame-ionization detection. The use of solvent evaporation techniques are not necessary. SFC, in the same way as LC, can be used to preseparate a sample into classes of compounds where the individual components can then be analyzed and quantified by GC. The supercritical fluid sample effluent is decompressed through a restrictor directly into a capillary GC injection port. In addition, this technique allows selective or multi-step heart-cutting of various sample peaks as they elute from the supercritical fluid... 

The question of the compatibility of metals and alloys with carbon and carbonaceous gases has assumed considerable importance in connection with the development of the gas-cooled nuclear reactor in which graphite is used as a moderator and a constituent of the fuel element, and carbon dioxide as the coolant. Tests of up to 1 000 h on a series of metals and nickel-containing alloys under pressure contact with graphite at 1 010°C" showed that only copper was more resistant than nickel to diffusion of carbon and that the high-nickel alloys were superior to those of lower nickel content. The more complex nickel-chromium alloys containing titanium, niobium and aluminium were better than the basic nickel-chromium materials. 

In addition to fuel and targets(15J6) from SRP reactors, SRP also reprocesses a wide variety of fuels from offsite research reactors and a wide range of unirradiated plutonium scrap materials.(17) Following customary Savannah River practice, initial processing of each offsite material is designed to transform the actinides to a solution that is compatible with one of the solvent extraction cycles in either of the separations areas. A major advantage of this practice is that the... 

The urea distribution network in Europe, around year 2006, would be limited to one distribution point for a 500 km radius area (heavy-duty vehicles compatibility - data to be checked and actualized), and would not allow a co-fueling strategy whose interests are the simultaneous fuel/urea filling up at the service-station and the minimization of the urea tank volume. Today, it is difficult to anticipate the consequences of EuroV. 

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