机械通风冷却塔变工况节能分析

Energy-saving analysis of mechanical ventilation cooling tower under variable conditions

采用麦克尔焓差方程建立数学模型,对200 t/h机械通风逆流冷却塔进行分析,研究了多种因素对冷却塔变工况的影响,并评价了变水流量及变风量的节能效果。分析结果表明:大气压力、干球温度的变化对冷却塔选型及运行影响很小,湿球温度、散热量、水流量以及风量的变化对其影响较大;同等情况下,水泵变频的节能效果优于风机变频。

A mathematic model of 200 t/h counter-flow cooling tower with mechanical ventilation is established by using Merkel enthalpy difference equation. The influence of various factors on the cooling tower’s off-design condition is studied, and the energy-saving effect of variable water flow and variable air flow is evaluated. The results show that the changes of atmospheric pressure and dry bulb temperature have little influence on the selection and operation of cooling tower, while the changes of wet bulb temperature, heat dissipation, water flow and air flow have great influence on it. Under the same conditions, the energy-saving effect of pump frequency conversion is better than that of fan frequency conversion.