集中供热系统板式热交换器污垢清洗后的能效特性研究

Energy Effficiency Characteristics of Plate Heat Exchanger in District Heating System after Fouling Cleaning

污垢降低热交换器传热系数,增加流动阻力,显著影响热交换器及供热系统的能效特性。为了研究污垢对集中供热系统换热站中板式热交换器的影响,本文对西安市5个居民小区的换热站的10台板式热交换器清洗前和清洗后分别进行了测试,对比其清洗前、后的传热流动与能效特性,估算了清洗后板式热交换器每个供暖季的节能量。实验表明清洗后板式热交换器传热系数、能效水平分别提高了11.6%和17.7%,相同传热量下换热机组的水泵运行功率平均减小38.1%,并可降低一次侧进回水温度,节能效果显著。

Fouling decreases heat transfer coefficient, increases the flow resistance, and significantly affects the energy efficiency of the heat exchangers. To investigate the influence of fouling on the plate heat exchanger in substation of the district heating system, this paper conducted performance tests on 10 plate heat exchangers in 5 communities in Xi’ an before and after cleaning respectively. The heat transfer and flow resistance of the plate heat exchangers before and after cleaning were compared, and the energy saving of each heating season after cleaning is estimated. The experimental results show that the heat transfer coefficient and energy efficiency of the plate heat exchanger are increased by 11. 6% and 17. 7% respectively, the operation power of the water pump in the heat exchange unit is reduced by 38. 1%, and the temperature of the primary inlet and return water can be reduced, which leads to remarkable energy saving.