Liquid fuels Liquids, storage

Direct Methanol Fuel Cell The liquid-fed direct methanol fuel cell (DMFC) is generally seen as the most viable alternative to lithium ion batteries in portable applications because DMFC systems require less ancillary equipment and can therefore potentially be more simphfied compared to an H2 PEFC. Additionally, the use of a liquid fuel simphfies storage. The DMFCs can potentially compete favorably with advanced Li ion batteries (which currently power many wireless portable apphcations) in terms of gravimetric energy density of 120-160 Wh/kg and volumetric energy density of 230-270 Wh/L. While both H2 PEFCs and DMFCs are strictly PEFCs (both use the same flexible polymer electrolyte), the DMFC feeds a liquid solution of methanol and water to the anode as fuel. The additional complexities of the low-temperature methanol oxidation reaction prevent the DMFC from... 

Confined combustion explosions (gaseous or liquid) usually occur when a flammable vapor leaks into an enclosure and mixes witJi air to form a flarmnable mix-ture, whereupon this mix+ure contacts an ignition source tliat was present before the leak occurred. This type of explosion ctm tUso occur in storage taitks or sliips where tlie vapor space above tlie stored flanunable liquid (fuel) is in tlie cxplosivity range. In tliis case, an ignition source accidentally introduced will cause an explosion. 

Hydrogen onboard storage systems for vehicles are bulkier, heavier, and costlier than those for liquid fuels or compressed natural gas, but are less bulky and less hca than presently envisaged electric batteries. Even with these constraints, it appears that hydrogen could be stored at acceptable cost, weight, and volume for vehicle applications. This is true because hydrogen can be used so efficiently that relatively little fuel is needed onboard to travel a long distance. 

The aniline clo d point is a measure of the paraffinicity of a fuel oil. A high value denotes a highly paraffinic oil while a low value indicates an aromatic, a naphthenic, or a highly cracked oil. The flash point represents the temperature to which a liquid fuel can be heated before a flash appears on its surface upon exposure to a test flame under specified conditions. A knowledge of the flash point is needed to ensure safe handling and storage without fire hazards. 

External to the boiler house, provision for the storage and handling of solid and liquid fuel is required with access for delivery vehicles. With some small boilers such as electrode or steam-coil generators, where the boiler only serves a single item of plant or process, it is practical to install them immediately adjacent to that process. The electrode boiler is eminently suitable here as no combustion gases are produced. 

A fuel gas under pressure which may be hydrogen, towns gas, acetylene or propane. With special nozzles, low-pressure acetylene or butane can be used, but it is not common practice. The use of single cylinders of fuel gas is now giving way (except under site conditions) to the gases drawn from bulk liquid storage. All modern installations use flowmeters in the gaseous feeds. 

A hydrogen fuel cell is environmentally friendly, but H2 is much more difficult to store than liquid fuels. The production, distribution, and storage of hydrogen present major difficulties, so researchers are working on fuel cells that use liquid hydrocarbon fuels. One such fuel cell is composed of layers of yttria-stabilized zirconia (YSZ), which is solid Zr02 containing around 5% Y2 O3. This cell uses the combustion of a... 

Until recently the atmospheric chemistry of nitrogen-containing compounds such as the hydrazines, which are widely used as fuels in military and space vehicles, has received comparatively little attention. N,N-dimethyIhydrazine (also UDMH = unsymmetrical dimethylhydrazine) is used in liquid-fueled rockets, and thus there Is a possibility that its use, storage, and handling could result in its release in the atmosphere. 

Incidental combustible liquid storage (e g., lube oil reservoirs, fuel day tanks, etc.) should normally not be installed within 1.8 meters (6 ft.) of an emergency exit route, especially if it is the only means of egress from an enclosure. 

If fuel cell cars run on gasoline, there is minimum disruption, but many predict that methanol will serve as a bridge to direct hydrogen. Early fuel cell cars may run on methanol, but rapid advances in direct-hydrogen storage and production could bypass any liquid fuel phase. 

Among liquid fuels (XTL), only biomass-derived hydrocarbons (BTL) are a relevant option from the perspective of lowering GHG emissions not so other fossil-based liquids (CTL, GTL). Even if CTL fuel supply paths were upgraded by carbon capture and storage, the resulting specific CCF-equivalent emissions would only be reduced to the level of conventional gasoline or diesel energy chains. 

One major advantage of DME use is that it can be stored as a high-density liquid phase at modest pressures (around 5 atm) and delivered as a gas-phase fuel in a pumpless operation. Therefore, the use of DME can potentially combine the advantages of easy fuel delivery of pressurized hydrogen and the high energy density storage of liquid fuel. In addition, DME is less toxic than methanol. 

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