摘要
采用单极层状冷冻方法淡化苦咸水,可以获得回收率高、质量好的冰晶.分别取500、1.000、2.000、3.000、5.000.mg/L苦咸水在-2、-4、-6、-8、-10、-12、-14、-16、-18、-20.℃的条件下冷冻,观察分析脱盐率、冷冻温度、冷冻速率、成冰率和苦咸水浓度之间的关系,结果表明:随着冷冻速率增大或者溶液浓度增加脱盐率下降,冷冻速率主要受冷冻温度影响,成冰率主要受冷冻速率和冷冻时间的影响,而溶液浓度对冷冻速率没有明显影响.随水样浓度由低到高,其最佳冷冻温度范围分别为:-6～-10.℃、-4～-8.℃、-6～-10.℃、-2～-6.℃和-2～-8.℃.在成冰率分别为9.5%、9.3%、7.0%、7.8%和8.5%时,各水样的脱盐率达到最高值,分别为94.3%、80.6%、64.8%、68.1%和59.2%.
Ice crystals of highquality can be obtained with high recovery rate in the process of brackish water desalination with unipolar layered freezing method.Brackish water with different concentrations of salt（500 mg/L,1 000 mg/L,2 000 mg/L,3 000 mg/L,5 000 mg/L）has been frozen at temperatures from-2 ℃ to-20 ℃ at a regular interval of 2 ℃ and relationships between the factors including desalination rate,freezing temperature,freezing rate,ice growth rate,and concentration of brackish water have been analyzed.Analysis results show that desalination rate declines with the increase of freezing rate and concentration of the samples.Freezing rate mainly depends on freezing temperature.Ice growth rate is mainly determined by freezing rate and freezing time,while the solution concentration has no effect on freezing rate.The optimum freezing temperature ranges for the samples with concentrations of 500 mg/L,1 000 mg/L,2 000 mg/L,3 000 mg/L,5 000 mg/L are-6—-10 ℃,-4—-8 ℃,-6—-10 ℃,-2—-6 ℃ and-2—-8 ℃,respectively.At the optimum freezing temperature,with the ice growth rates of 9.5%,9.3%,7.0%,7.8% and 8.5%,the desalination rates for the brackish water samples reach the maximums of 94.3%,80.6%,64.8%,68.1% and 59.2%,respectively.
出处
《天津大学学报》
EI
CAS
CSCD
北大核心
2010年第5期429-434,共6页
Journal of Tianjin University(Science and Technology)
基金
科技部"十一五"科技支撑计划资助项目(2006BAK30B02)
关键词
冷冻法
苦咸水
脱盐率
冷冻速率
成冰率
freezing method
brackish water
desalination rate
freezing rate
ice growth rate
