Fuels for power plants

Table 10.6 shows some of the major components of fuels that are used in power plants. The coal and heavy fuel are the conventional fuels for power plants, while the Orimulsion is a relative new product from Venezuela, which is attractive owing to a higher hydrogen content that leads to reduced emission of CO2. 

CCL [Catalytic coal liquids] A catalytic process developed by Gulf Oil Corporation. The main objective is the production of clean-burning liquid fuels for power plants. 

Natural gas is considered to be one of the cleanest fuels for power plants and potentially for automobiles. The composition of natural gas varies widely depending strongly on its source. A gas sample may contain anywhere from... 

In 2002, a prominent collection of scientists wrote, Biomass plantations can produce carbon-neutral fuels for power plants or transportation, but photosynthesis has too low a power density ( 6 W/m2) for biofuels to contribute significantly to climate stabilization. These researchers find the scale of our growing energy demand so daunting that they conclude that none of today s current options for renewable energy or energy efficiency are up to the... 

The capacity of a power plant is assumed to be lOOMW. Fuel for power plants is produced by the liquefaction and gasification of eucalyptus. Its heat of combustion is assumed to be 16.7MJ/kg-dry basis. The annual growth rate of biomass in a plantation area is assumed to be 1.25kg-dry woodW. The plantation - harvesting cycle is 10 years. The area of the plantation site required for the lOOMW plant is calculated to be about 600km. ... 

Problem Nuclear engineers use chlorine trifluoride in the processing of uranium fuel for power plants. This extremely reactive substance is formed as a gas in special metal containers by the reaction of elemental chlorine and fluorine. 

Many passes are made, each increasing the fraction of UFg until a mixture is obtained that contains enough UFg. This isotope-enrichment process was developed during the latter years of World War II and produced enough for two of the world s first three atomic bombs. The principle is still used to prepare nuclear fuel for power plants. 

Coal is an important fuel for power plants. Its transportation in the form of slurry has received considerable attention since the successful construction of the Black Mesa Pipeline (Figure 11-1). In fact, one of the longest slurry pipelines is the ETSl coal pipeline, built in 1979. It spans a distance of 1670 km (1036 miles), uses a 965 mm (38 in) pipe, and transports 23 million metric tons/year (25 US tons/year). In Russia, the Siberian coal pipeline is 260 km (163 mi) long and transports 4 million tons of coal a year from Siberian mines. 

Conventional fossil fuel-fired power plants, nuclear power faciUties, cogeneration systems, and combined-cycle faciUties all have one key feature in common some type of steam generator is employed to produce steam. Except for simple-cycle cogeneration faciUties, the steam is used to drive one or... 

Fossil Fuel-Fired Plants. In modem, fossil fuel-fired power plants, the Rankine cycle typically operates as a closed loop. In describing the steam—water cycle of a modem Rankine cycle plant, it is easiest to start with the condensate system (see Fig. 1). Condensate is the water that remains after the steam employed by the plant s steam turbines exhausts into the plant s condenser, where it is collected for reuse in the cycle. Many modem power plants employ a series of heat exchangers to boost efficiency. As a first step, the condensate is heated in a series of heat exchangers, usually sheU-and-tube heat exchangers, by steam extracted from strategic locations on the plant s steam turbines (see HeaT-EXCHANGETECHNOLOGy). 

Sulfuric acid (H1SO4) and ammonium bisulfate (NH4HSO4) contribute importantly to ambient acid aerosols, particularly in geographic locations where sulfur-rich coal is used for power plant fuel, such as the eastern United States.Studies on animals and human subjects have shown that H2SO4 and NH4HSO4 alter mucociliary transport in a dose-dependent fashion and... 

An economic externality exists whenever the wellbeing of some individual is affected by the economic activities of others without particular attention to the welfare of that individual. For example, smog-related illnesses such as bronchitis and exacerbated cases of childhood asthma have been blamed, to some extent, on the emissions of nitrogen oxides from automobiles and large fossil-fuel-burning power plants. These illnesses have high treatment costs that are not... 

Fhosphoric acid does not have all the properties of an ideal fuel cell electrolyte. Because it is chemically stable, relatively nonvolatile at temperatures above 200 C, and rejects carbon dioxide, it is useful in electric utility fuel cell power plants that use fuel cell waste heat to raise steam for reforming natural gas and liquid fuels. Although phosphoric acid is the only common acid combining the above properties, it does exhibit a deleterious effect on air electrode kinetics when compared with other electrolytes ( ) including such materials as sulfuric and perchloric acids, whose chemical instability at T > 120 C render them unsuitable for utility fuel cell use. In the second part of this paper, we will review progress towards the development of new acid electrolytes for fuel cells. 

The fuel eell is a nineteenth eentuiy invention in the twentieth eentury it heeame the heart of an eleetroehemical power plant and power souree, whieh is now in a stage of advaneed technology development. Its first and only applieation since the early 1960s, has been as an auxiliary power souree for spaee flights by the National Aeronautics and Space Administration (NASA). During the past decade, development for terrestrial (eivihan and defense) applieations has led to its commercialization and research on utilization in a variety of applications. Programs in the United States, Japan, Europe, and some other eoimtries are focused on the development of fuel cell power plant/power sources for (1) base-load,... 

The enthusiasm for developing DMFCs (the fuel cell researcher s dream) evolved in the 1960s, which was really the boom period for R D activities on all types of fuel cell technologies, mainly because of NASA s vital need for fuel cell power plants for space vehicles. As early as the 1960s it was recognized that the major challenges in developing DMFCs... 

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