冷却塔低温余热利用系统

Low temperature waste heat utilization system for cooling towers' attachments

针对冷却塔低温余热利用系统,给出了系统有机工质选取原则和热管换热器设计思路,建立了系统热力学模型。以低温热源参数、冷却水温度、戊烷类工质参数为系统初始参数,通过系统热力学模型计算得出系统最大热效率>13%。若冷却塔低温余热利用系统用于发电,每年运行时间按照7 000h,年发电量为700 000kW,电价按照0.5元/(kW·h)计算,年收益可达35万元,相当于减少CO2排放量650t,经济和环保效益显著。

By establishing thermodynamic model and system performance evaluation system for waste heat utilization system of cooling towers＇ attachment,the selecting principle of organic fluids was investigated,and the design theory of the heat pipe heat exchangers was studied.Taking the condition with low temperature heat source temperature of 85℃,the flow rate of 100t/h,the cooling water temperature of 25℃and the pentane as the fluid as the example,corresponding calculation was carried out.The results show that,the heat efficiency of the system was larger than 13%;the annual power generation was 7.0×10^5 kWh if the working time is 7.0×10^3 h per year;assuming the electricity price is 0.5yuan/（kW·h）,the annual economic benefit can reach up to 3.5×10^5 yuan;at the same time,the CO2 emission can be reduced by 650 t.