Furnaces solar

Solar furnace capable of generating temperatures greater than 9,300°F becomes operational in Japan for scientific research. ... 

Fibers of titanium diboride can be prepared by reaction (a) at 400°C in an electrical discharge. Adherent layers of certain metal borides on metal substrate surfaces are obtained by thermal decomposition of metal (Mo, W, Nb, Ta) halides and BBr3 on a metallic substrate using a solar furnace or induction heating ... 

Steinfeld et al. [133] demonstrated the technical feasibility of solar decomposition of methane using a reactor with a fluidized bed of catalyst particulates. Experimentation was conducted at the Paul Scherrer Institute (PSI, Switzerland) solar furnace delivering up to 15 kW with a peak concentration ratio of 3500 sun. A quartz reactor (diameter 2 cm) with a fluidized bed of Ni (90%)/Al2O3 catalyst and alumina grains was positioned in the focus of the solar furnace. The direct irradiation of the catalyst provided effective heat transfer to the reaction zone. The temperature was maintained below 577°C to prevent rapid deactivation of the catalyst. The outlet gas composition corresponded to 40% conversion of methane to H2 in a single pass. Concentrated solar radiation was used as a source of high-temperature process heat for the production of hydrogen and filamentous... 

Some early studies considered solar furnaces to drive conventional turbines, but as the efficiency of the solar cell improved, this concept seemed less practical. 

The main challenge with storing in terms of oxidation of reactive metals is the reversibility and the control of the thermal reduction process in order to produce the metal in a solar furnace, where Na and Li have a gravimetric hydrogen derrsity of 3 mass% and 6.3 mass%, respectively. 

The separation of rare earth oxides at 2500° C in a Solar furnace has been attempted [48], and Ce4+-oxide was obtained in a pure state from its mixture with lanthanum oxide. 

The successful performance of Mondouis solar furnace led to the use of its design as the prototype for the next three large single hcliostat-concentrator solar furnaces which were to he built during the next twenty years. All three of these furnaces were similar to the Montlouis furnace... 

The CNRS 1,000 kilowatt solar furnace is located at Odeillo, Font-Romeu, altitude of 5,900 feet (1798 meters) about 25 miles (40 kilometers) east of Andorra and 5 miles (8 kilometers) west of Montlouis. At this location, the sun shines as many as 180 days a year and solar intensities as high as 1,000 watts per square meter are common. The solar furnace was completed on October 1, 1970, after more than 10 years of construction. 

Figure 11 is a schematic of the CNRS 1,000-kilow att solar furnace. This furnace utilizes 63 heliostats to direct the sun s rays onto the surface of the giant parabolic concentrator. 

Fig. 11. Schematic representation of die 1000-kiluwaU solar furnace at Odeillo. Font-Romeau, France. (Centre National de la Recherche Scientifique)...

Fig. 12 Large parabolic reflector and focal building in foreground. Concentrated energy is directed at the solar furnace located within the focal building. Installation is at Odeillo, Font Romeu, France. Photo by Glenn D. Considine)...

Rg. 14. Solar energy versus distance from focal point in Odeillo solar furnace. (Georgia Institute of Technology )... 

Solar Furnaces No Longer Uncommon. The past decade has brought increased interest in using solar energy for industrial processes, not just to conserve energy or avoid the use of fossil fuels. Some of the important installations, as of the early 1990s, are listed in Table 1,... 

The time required to bring a part to trealing temperature also is an important consideration. Solar furnaces have no competition on this point. See Table 2. 

TABLE 2. SOLAR FURNACE TIME TO REACH MELTING POINT OF MATERIALS... 

The use of solar energy in chemical processing has also been investigated. Studies describe, for example, the cycloaddition reaction of a carbonyl compound to an olefin carried out in a solar furnace reactor (91) or oxidation of 4-chlorophenol in a solar-powered liber-optic cable reactor (92). The concept of using solar light for the synthesis of e-caprolactam was evaluated, and it was shown that the return on investment was better than for the conventional technology (93). Solar reactors can also be used advantageously in water treatment plants (94). 

Marcus, R. J., and H. G. Wohlers Flow systems in the solar furnace and the photolysis of nitrosyl chloride. Solar Energy 5, 121 (1961). 

Solar furnace Solar rays focused on a metal doped graphite target. Growth dynamics similar to PLV 1.4 Good quality CNTs, little amorphous carbon. Spreading not expected in the near furture... 

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