太阳能直热式海水淡化系统热经济孤立化研究

The Research of Thermo Economic Isolation on Direct Heated Solar Seawater Desalination System

为了提高直热式太阳能海水淡化系统的设计与操作,运用热经济孤立化方法,对直热式太阳能海水淡化系统进行分析,获得了系统最优化操作参数。同时讨论了设备使用年限、最高海水温度、进料海水单价对年度化费用的影响。结果表明:当拉格朗日乘子分别为$4.85/kJ、$0.59/kJ、$0.40/kJ、$0.19/kJ时,系统实现热经济孤立化。此时,闪蒸温度为58.6℃,蒸发温度为35℃时,年度化费用为$4 332.81/a。年度化费用随设备使用年限的增加而减小,随最高海水温度的升高而降低,随进料海水单价的升高而增加。

Applied the method of thermo economic isolation, the direct heated solar seawater desalination system is analyzed to obtain the optimum operation parameters. Besides, the effects of equipment life, the highest seawater temperature and exergy price of feed seawater on annual cost were discussed. The results show that when Lagrange multipliers are ￥4.85/kJ、￥0.59/kJ、￥0.40/kJ、and ￥0.19/kJ, the system＇s thermo economic isolation is realized. Flash temperature is 60 ℃, evaporation temperature is 35 ℃ and annual cost is ￥4 332. 81/year under this condition. The annual cost declines with extending of equipment life and increasing of the highest seawater temperature and mounts up with rising of exergy price of feed seawater.