Heating systems economics

The alternative of lower cost r-f systems, ie, induction and r-f heating systems at 40 MH2 and below, should be considered (96) (see also Furnaces, electric). More extensive discussions of the economic aspects of microwave systems and payback calculations are available (97,98). 

The variation in temperature across the top and bottom halves of the mold is a function of the press platen size, the flatness of the mold and platen surfaces at the two mold/platen interfaces, the mold construction, and the platen heating system. The larger the platen size, the more difficult it is to maintain a constant temperature across the platen. Therefore, one solution to the problem is to use a large number of molding presses with a relatively small platen size, for example, four presses with platens 355 x 355 mm will have approximately the same production capacity as one press with a 710 x 710 mm platen. In reality, for high-volume production, large presses are more economical from the cost point of view and the floor space required. 

Heat transfer systems are normally provided to utilize available process heat, to economize heat for distillation purposes or to preheat fuel supplies before usage. They are generally considered a secondary process support system to the main production process, however they may be so critical to the process that they might be considered a single point failure if not adequately designed. 

Air-to-air flue economizers are also available for about 1/5 the cost but these save much less energy and are usually not tied into the central heating system. They are best for heating spaces near the flue. 

The economics of power generation can be highly improved if the heat, which otherwise would be wasted, can be sold. Therefore the combined heat-power systems ( co-generation ) provide a solution with maximum economic benefits. The best way of waste heat utilization is the use of heat in a district heating system, which can take up the substantial heat load. 

Conversion of hunters and other design aspects of heating systems and appliances to pure hydrogen, or to a hydrogen-enriched natural or substitute natural gas supply, while costly and inconvenient, is certainly not in the economically insurmountable category. Similar alterations over the years were made in Ihe United States when communities switched from manufactured gas (about 5tlr- hydrogettt to natural gas. Such switchovers arc ever) more recent in European communities. 

Economics Basis is a 200,000-tpy standard plant, West German conditions, December 2000, including compressor station, incinerator for wastewater and offgas, hot-oil heating system and catalyst... 

With regard to the heat market, a light-water reactor (LWR) of the size of the German Biblis A reactor (1200 MW(e)) has the potential to provide 10,(XX) GJ/h low-temperature heat in the CHP mode. Since hot water and process steam cannot be transported directly over long distances, nuclear power can be economically used only in areas with large heat consumption density like chemical industrial complexes, or in long-distance heating systems [4]. With respect to the latter, some of the candidate systems are operated at lower temperatures and could be used in connection with an LWR, if the catalyst conversion processes can be properly controlled [14]. 

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