Analysis of Different Types of Dry-Wet Cooling Towers,

摘要

Computer models have been developed to study the thermodynamic and economic performance of various types of combination dry-wet cooling towers. The models consider the basic thermodynamics of wet and dry heat transfer,steam turbines,and condensers,the influence of different power loading patterns and changing meteorological conditions,and the various economic parameters. In the latter category are the capital costs associated with the equipment as well as the lost capacity at extreme meteorological conditions,and the operating costs resulting from fuel consumption,cooling water usage,maintenance of the cooling systems,internal power requirements,and under-production of energy. It is found that parallel air-path towers are more flexible and effective than comparable series air path configurations. Of the different types of parallel air path towers,the most favorable one is also the simplest,namely the one in which separate dry and wet units of conventional design are utilized simultaneously. Finally,it is evident that combination dry-wet cooling towers are economical in comparison with conventional wet towers when the cost of water is sufficiently high.