对增湿除湿型太阳能海水淡化装置中填充空心塑料小球作为堆积床的传质系数进行了实验测试,并与其他材料堆积床的传质系数进行了比较。介绍了测试装置的结构和工作过程,给出了传质系数随不同运行参数的变化关系。实验结果表明,该空心塑料小球由于具有较大的润湿表面和内部具有储水多孔材料,因而具有较高的蒸发传质系数。在系统冷却水和喷淋温度分别为25℃和80℃时,传质系数比使用方木条时提高了约8%。实验结果还说明,喷淋量及循环风量对传质系数的影响一般是正向的,喷淋量及风速增加,传质系数将增加,但风速达到一定程度后,增加循环风量使传质系数增加幅度变小。
This paper performed experimental tests on the mass transfer coefficient of humidification and dehumidification solar desalination device filled with hollow plastic ball as a packed bed and compared with the mass transfer coefficients of other material packed beds.We introduce the structure and operation of the test device and present the relationship of the mass transfer coefficient changing with different operating parameters.The experimental result indicates that this hollow plastic ball has a relatively high evaporation mass transfer coefficient due to the relatively high wet surface and interior porous water storage material.When the cooling water system and spray temperatures are25℃ and 80℃,the mass transfer coefficient is about 8%higher than that using square wood as a packed bed.The experimental result also indicates that the effect of spraying amount and circulating flow on the mass transfer coefficient is generally positive,i.e.,the mass transfer coefficient increases with the spraying amount and wind speed.However,when the wind speed reaches a certain extent,the increase of mass transfer coefficient with the circulating flow will become smaller.In addition,the concentration of sea water also has a great influence on the mass transfer coefficient.