外文翻译饮用水处理通过用金属膜制成的凝固—微滤来去除天然有机物质毕业论文.docVIP

外文资料 Removal of natural organic matter (NOM) in drinking water treatment by coagulation–microfiltration using metal membranes Torove Leiknes?, Hallvard ?degaard, H?vard Myklebust Department of Hydraulic and Environmental Engineering, NTNU, Norwegian University of Science and Technology, S.P. Andersensvei 5, N-7491 Trondheim, Norway Abstract Drinking water sources in Norway are characterized by high concentrations of natural organic matter (NOM), low pH, low alkalinity and low turbidity. The removal of NOM is therefore in many cases a general requirement in producing potable water. Drinking water treatment plants are commonly designed with coagulation direct filtration or with NF spiral wound membrane processes. This study has investigated the feasibility and potential of using inorganic metal microfiltration membranes in a submerged membrane configuration with coagulation pre-treatment for drinking water production. Variations in operating modes and conditions were tested, from dead-end operation to semi sequencing batch operation using air scouring and backwashing cycles for membrane cleaning and fouling control. Fluxes around 180 LMH at trans membrane pressures below 0.3 bar where achieved over production cycles in excess of 50 h. Treatment efficiencies in general showed 95% colour removal, ～85% UV removal, 65–75% TOC removal and 0.2 NTU turbidity and non-detectable suspended solids in the permeate. The initial results show that MF metal membranes is an interesting alternative to sand filtration in coagulation/direct filtration for treating drinking water. Keywords: Natural organic matter、Coagulation–microfiltration、 Metal membranes 1. Introduction About 90% of Norwegian drinking water supplies are from surface water sources, generally from lakes which typically have very low turbidity, alkalinity and hardness but high colour resulting from natural organic matter (NOM). One of the major problems of using surface water sources in northern climates is high content o