摘要
采用3种不同无纺布作为支撑体的聚偏氟乙烯(PVDF)超滤膜为基膜,以哌嗪为水相单体、均苯三甲基酰氯(TMC)为有机相单体,通过界面聚合的方法制备出聚酰胺(PA)管式复合纳滤膜。配制质量浓度为2000~70000 mg/L的Na_(2)SO_(4)溶液,在0.4~1.5 MPa的测试压力下运行PVDF/PA管式膜组件,研究高盐与高压对该管式复合膜分离性能的影响,通过扫描电镜和荷电性测试结果分析高压对管式纳滤膜的影响。结果表明,管式纳滤膜的通量随着测试压力的增大、Na_(2)SO_(4)溶液质量浓度的减小而增大;截留率则随运行压力的增加呈先增加后减小的趋势,随Na_(2)SO_(4)溶液质量浓度的增加而减小;无纺布的强度和性能对管式纳滤膜的应用性能也有很大影响。在2000~10000 mg/L的原液中,运行压力最好选择0.6 MPa;在20000~70000 mg/L的原液中,运行压力优先选择1.0 MPa。运行压力不能超过管式纳滤膜能承受的最大压力,但要高于硫酸钠溶液的渗透压,才能更好地发挥管式纳滤膜的分离性能。
Polyvinylidene fluoride(PVDF)ultrafiltration membranes with three different non-woven fabrics as the support were used as the base membrane,and polyamide(PA)tubular composite nanofiltration membranes were prepared by interfacial polymerization using piperazine as the aqueous phase monomer and trimethyl benzene chloride(TMC)as the organic phase monomer.Na_(2)SO_(4) solutions with mass concentrations ranging from 2000 to 70000 mg/L were prepared,and PVDF/PA tubular membrane were operated at test pressures of 0.4 to 1.5 MPa.The effects of high salt and high pressure on the separation performance of the tubular composite membrane were investigated.The effects of high pressure on tubular nanofiltration membrane were analyzed by scanning electron microscopy and charge test results.The results showed that flux of the tubular nanofiltration membrane increased with the increase of pressure,the decrease of mass concentration of Na_(2)SO_(4) solution.The retention rate tended to increase and then decrease with the increase of the operating pressure,and decreased with the increase of the mass concentration of Na_(2)SO_(4) solution.The strength and performance of non-woven fabric also had a great influence on the application performance of tubular nanofiltration membrane.In the raw solution of 2000-10000 mg/L,the operating pressure of 0.6 MPa was preferred.In the raw solution of 20000-70000 mg/L,the operating pressure of 1.0 MPa was preferred.The operating pressure should not exceed the maximum pressure that the tubular nanofiltration membrane can withstand,but should be higher than the osmotic pressure of sodium sulfate solution in order to better utilize the separation performance of tubular nanofiltration membrane.
作者
李士伟
刘恩华
杨利娟
胡苏皓
LI Shiwei;LIU Enhua;YANG Lijuan;HU Suhao(Laboratory of Hollow Fiber Membrane Material and Membrane Process,Tianjin Polytechnic University,Tianjin 300387,China;Tianjin Hipure Membrane Technology Co.,Ltd.,Tianjin 300304,China)
出处
《工业水处理》
CAS
CSCD
北大核心
2022年第8期128-135,共8页
Industrial Water Treatment
基金
天津市科技计划项目(16PTGCCX00070)。
关键词
管式纳滤膜
高浓度盐
工业废水
tubular nanofiltration membrane
high concentration salt
industrial wastewater
