Water Conservation Analysis for a Cooling Tower

• Main Authors: Po-Cheng Hsieh, 謝博丞
• Other Authors: Jenq-Shing Chiou
• Format: Others
• Language: zh-TW
• Published: 2004
• Online Access: http://ndltd.ncl.edu.tw/handle/81850277162726390978

碩士 === 國立成功大學 === 機械工程學系碩博士班 === 92 === Cooling tower is the heat-exchange equipment, which reduces the temperature of recirculating cooling water by evaporating a part of recirculating water. This is why the water consumption in the cooling tower is inevitable. However, the actual water loss for a cooling tower is usually much more than it is necessary. The amount of unnecessary water loss will become enormous if many high-capacity cooling towers exist in the same water district. In this thesis, four kinds of water loss were identified for a typical open-recirculation cooling tower, which are evaporation loss, drift loss, splash loss, and blow-down loss. Based on the data collected from actual field investigation and analysis, the order of loss magnitude is sequentially to be evaporation, blow-down, splash, and drift losses. From the view point of water conservation, the largest margin to reduce the water loss is by cutting down the unnecessary evaporation loss, which can be effectively achieved if the recirculating water flow rate and the amount of cooling air can be automatically modulated by the actual weather condition and the actual cooling load. More water conservation can be realized in blow-down loss when the ultra-filtration / nano-filtration technique combined with a moderate anti-scale treatment is used to improve the quality of recirculating water, and the water quality is assured by on-line sensors.