摘要
采用超滤膜(UF)为核心,以混凝作为预处理措施,对混凝-超滤工艺处理径流雨水的特性和膜通量变化与污染现象进行了研究,并对聚合硫酸铁(PFS)单独混凝、UF、PFS-UF组合工艺进行了对比;在优化混凝基础上,考察了混凝-UF对常规水质指标及总磷、生物可同化有机碳(AOC)、可生物降解溶解性有机碳(BDOC)等生物稳定性指标的去除效果.结果表明,混凝可有效去除TOC、UV254和总磷,混凝剂投加量与污染物去除近似呈线性关系.各混凝剂除浊效能均良好.综合考虑混凝处理效率与经济性,实验采用混凝方案为10 mg·L-1的PFS.PFS、UF、PFS-UF工艺除浊率均在95%以上,PFS和UF对TOC和UV254的去除较为接近,采用PFS-UF可提高去除率13%—15%;PFS-UF处理后雨水的AOC、BDOC分别降低至61.8μg·L-1、0.19 mg·L-1,残余总磷可降至3.8μg·L-1,雨水生物稳定性明显提高.PFS、UF和PFS-UF对颗粒物的去除率分别达80.5%、99.6%和99.9%.膜通量的变化和SEM图分析表明,混凝在一定程度上减轻了UF膜污染;形成的凝胶层具有一定整体强度,水力清洗时易于清除,膜通量恢复较好;但同时凝胶层的产生也增大了透膜阻力,PFS-UF工艺的周期内膜通量衰减有增加的趋势.
As an available water resource,rainwater has drawn growing concerns. UF membrane was adopted as a core technique and coagulation as a pretreatment process in this study. The characteristic of purification and the variation of membrane flux were studied,and PFS,UF,PFSUF process were compared. Removal of routine water indexes and biological stability indexes such as phosphorus,AOC,BDOC was examined on the basis of coagulation optimization. Results indicated that coagulation was efficient to remove TOC,UV254 and phosphorus. There was a linear dependence between the coagulant dosage and removal efficiency. Turbidity could be eliminated efficiently by AS,PAC and PFS. 10 mg·L- 1PFS was considered as the preferable coagulation scheme in this study. Removal of turbidity was above 95% using PFS,UF,PFS-UF. A similar removal rate ofTOC and UV254 was achieved by PFS and UF process respectively. But in PFS-UF process it increased by 13% to 15%. AOC and BDOC was cut down to 61. 8 μg·L- 1and 0. 19 mg·L- 1,which contributed to biological stability considerably. Removal of particulate matters by PFS,UF and PFS-UF was 80. 5%,99. 6% and 99. 9%,respectively. The variation of membrane flux and SEM experiments stated that coagulation eased the contamination of UF membrane. The formed gel layer had a certain strength and was removed easily by backwash,which was propitious to the recovery of membrane flux. But the resistance was accreted and the attenuation of membrane flux was accelerated also.
出处
《环境化学》
CAS
CSCD
北大核心
2015年第6期1142-1149,共8页
Environmental Chemistry
基金
广东省研究生教育创新计划项目(2013JGXM-ZC01)
广东省科技计划项目(2013B020800005)资助
关键词
雨水
混凝
超滤(UF)
生物稳定性
颗粒物.
runoff rainwater coagulation ultrafiltration（UF） biological stability particulate matter
