操作条件对NF90膜软化水过程的影响

Influences of Operating Conditions on Water Softening with NF90 Membrane

以模拟硬水为水样,针对压力、温度和pH值等操作因子对NF90型纳滤膜软化水过程的影响进行了试验研究。结果表明,在处理暂时硬度为300 mg.L-1(以CaCO3计)的硬水时,NF90膜有较高的通量和Ca2+截留率,适用于水质软化过程。在操作压力为0.5～2.0 MPa、温度为13℃～37℃、水样pH值为6.0～8.0的条件下,膜通量随操作压力、温度的升高而升高,但受pH值的影响不大。在试验条件范围内,Ca2+的截留率均>97%。

Influences of the operating pressure, temperature and pH values on softening the slmulated bicaroonate solutions with NF90 membranes were reported in the paper. The results indicated that when filtrating solutions with hardness of 300 mg·L^-1 （calculated as CaCO3）,the NF90 membrane was suitable for water softening as it had high flux and Ca^2＋ rejections. When the operating pressures were 0.5-2.0 MPa, the temperatures ranged in 13℃-37℃, and the feeding pH values ranged in 6.0-7.5,the membrane flux increased with the increase of operating pressure and the temperature, but was slightly influenced by the feeding pH values. The Ca^2＋ rejections were all more than 97% under the experimental conditions.