Reducing Water Consumption of Power Plant Utilizing Dry-Cooling Tower with Downfall Water

Authors

Abstract

The water consumption of steam power plants is one of the big challenges in the world. One of the suggested methods for reducing water in these power plants is the utilization of forced dry cooling tower. However, these types of cooling towers are dependent on weather conditions and reduced power plant efficiency. One way to solve this problem is to downfall water on it during hot hours. In this article, the forced dry and cooling towers are studied analytically. Then, with the consideration of characteristics of a power plant, the size and characteristics of dry and wet cooling towers are computed according to design temperature. These results are compared with experimental data and wet cooling towers of a power plant, and their accuracy has been verified. Only at temperatures higher than the design temperature is water falling on the tubes and fins of cooling tower. Using data from the weather station of power plant location, the numbers of hours when the ambient temperature has been higher than the design temperature are calculated and water consumption is computed. Calculations show that for a power plant of 320 MW at design temperature of 30°C, ninety seven percent (97%) of the water consumption can be saved. The loss of power output due to the use of dry cooling tower electric fans and pumps is 3.93 percent of output power.

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