Thermal Plants

Solar-thermal technology uses tracking mirrors to concentrate sunlight onto a receiver. In turn, the receiver absorbs solar energy as heat, warming a fluid that then drives a turbine generator. Most solar-thermal plants requite cooling water. 

As pointed out in Chapter 7, the amount of CO2 produced by a thermal plant is now a major criterion of its performance, for environmental and therefore economic reasons. 

By the early 1930s, thermal cracking had achieved a fairly high level of operation. Both the Dubbs (UOP) and Tube-and-Tank (Jersey Standard) Processes represented the state of the art in the field. Between the end of World War I, when the Burton Process was still revolutionary, and the early 1930s, octane ratings of gasoline increased 36 percent. This improvement resulted from the existence of more advanced thermal plants and the increasing use of additives, espe-... 

Sensible heat losses from thermal plant should be kept to a realistic minimum by the use of correctly specified insulation. There will be a point beyond which further... 

Despite the recent debates, few would disclaim that the net environmental benefits of hydropower are far superior to fossil-based generation. Hydroelectricity is produced for an average of 0.85 US0 per kWh. In comparison with hydropower, thermal plants take less time to design, obtain approval, build and recover investment. 

Today, the largest solar power plant in the United States is the 22-year-old thermal plant in California s Mojave Desert, which has a combined total capacity of 354 mW. At Kramer Junction, California, nine solar power plants, each 30 mW or larger, have been in operation for two decades. The yearly insolation in the area is 2,940 kWh/m2. Plant efficiencies range from 10 to 17%, and their capital costs range from 2,500 to 3,500 per kWp The cost of generated electricity from these plants drops as their size increases, and ranges from 10 to 17 /kWh. 

Sulfur dioxide is generated in flue gas as a result of combustion of fossil fuel in, for example, thermal plants. Although the sulfur dioxide content in the flue gas is usually small, namely below about 0.1-0.4 vol.% [86], the volume of the produced gas is so large that considerable amounts of sulfur dioxide contaminate the atmosphere, and therefore proper desulfurization becomes important. Here, absorption of SO2 by the sodium method is considered as part of the combined chemical/biological process shown in Fig. 9.21. The process includes SO2 removal, NaHCCh recovery, and elemental sulfur production [70]. 

Kotas T J, 1995, The Exergy Method of Thermal Plant Analysis, Krieger Malabar, FL. 

A further promising field for application of pyrolysis (not a topic of this chapter) seems to be the coupling of the pyrolysis units with a thermal plant. The pyrolysis fractions can be used as precleaned feed support for the combined power plant as shown in Table 20.1 for ConTherm at Hamm-Uentrop with a capacity of 100000 l/yr high caloric feed [15, 17]. 

Laboratory of Steam Boilers and Thermal Plants, Mechanical Engineering Department, National Technical University of Athens, 9 Heroon Polytechniou Ave 15780 Zografou, Greece... 

Table 4 shows evaluation results. We can see from Table 4 that introducing the proposed systems has the potential of generating 8.67 GW and of saving 12.0% of NG (29.178 million ton) consumed in NG-firing thermal plants in Japan in the year 1993 and that it has the potential of reducing CO2 emission of 9.62 x 10 t/y. 

Location Thermal plant Cristobal Colon, Huelva... 

Thermal plants Anionic and cationic tanks Soft natural rubber, Neoprene, ebonite... 

The corrosion of the metallic materials, is one of the most damaging factors that destroy economical and ecological resources, and many problems encountered in thermal plants for... 

Many problems encountered during the operation of thermal plants for electrical power production are related to corrosion in a more or less direct way. 

RO plants are, however, much more sensitive to insufficient feedwater pretreatment than thermal plants. For this reason, it is accepted technology to use well water from wells drilled at the seashore rather than surface water as in thermal desalination. 

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