Dry/wet cooling towers with ammonia as intermediate heat exchange medium

Engineering conceptual studies were made of several dry cooling towers for a 500 MW/sub e/ power plant. The most economical method used ammonia as a heat exchange medium. The ammonia condenses the turbine steam in a condenser-reboiler while being evaporated itself. The ammonia vapor is condensed and then recycled from a dry cooling tower. The lowest cost approach utilized a water deluge on the tower during the hottest ambient conditions to effect water savings of 80 percent over an all evaporative system. The total capital, and capitalized operating cost saving for the deluged/ammonia cooling system over a conventional wet/dry tower is potentially 15 to 30 percent for a typically $30 million tower.