浸没式膜过滤技术处理渤海海水的效果研究

EFFECT OF SUBMERGED MEMBRANE FILTRATION TECHNOLOGY ON THE TREATMENT OF SEAWATER OF THE BOHAI SEA

采用经澄清工艺处理后的渤海曹妃甸近岸表层海水进行浸没式膜过滤技术处理效果及稳定性研究。通过中试,优化选择了浸没式膜过滤系统的最佳运行压力,考察了出水指标。结果表明,浸没式膜过滤系统采用恒压运行,优化运行压力为-75 k Pa,产水通量不低于56 L/(m2·h),适当的气水反冲洗和气擦洗可有效的缓解膜堵塞的问题;浸没式中空纤维膜对大于700 nm颗粒粒径的细微悬浮物截留效果较好,系统出水浊度为0.15 NTU、UV254为0.003 cm-1、CODMn为0.29 mg/L、SDI平均为2.42,Fe3+的质量浓度平均为0.05 mg/L、活性硅酸盐的质量浓度为1.54μg/L。出水指标完全满足反渗透进水的要求,可用于海水淡化预处理。

Effect and stability of submerged membrane filtration technology were studied on treatment of coastal surface seawater of Caofeidian,the Bohai Sea,with application of a clarification process.The optimum operating pressure of this submerged membrane filtration system was selected and optimized,and water discharged indicators were investigated through the pilot test.The results showed that：when it was running under a constant pressure,the optimum operating pressure was-75 k Pa and permeate flux was not less than 56 L/（m^2·h）; Appropriate air and water backwash and gas scrubbing could alleviate the problem of clogging of the membrane effectively; Submerged hollow fiber membrane had a good rejection to the micro suspended solids which hold particle size greater than 700 nm; In its effluent,the turbidity was 0.15 NTU,UV254 was 0.003 cm^-1,CODMnwas 0.29 mg/L,the average of SDI was 2.42,average mass concentration of Fe3＋was 0.05 mg/L,and mass concentration of active silicate was 1.54 μg/L.Water discharged met the requirements of reverse osmosis inflow and the system could be used for the pretreatment of the further desalination.