Development of Effective Cleaning and Pre-treatment for Membrane Filtration

膜过滤有效清洗和预处理的开发

• 批准号: 12450210
• 负责人: WATANABE Yoshimasa
• 金额: $ 5.25万
• 依托单位: Hokkaido University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 2000
• 资助国家: 日本
• 起止时间: 2000 至 2001
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-12450210/
• 关键词: Membrane Filtration; Fouling; Back Washing; Air-Scrubbing; Coagulation; Sedimentation; Ozonation; Irreversible Cake Resistance; 生物膜; 不可逆ケーキ属; AOC; マンガン酸化; アンモニア酸化; スポンジ洗浄; 膜ろ過; 膜ファフリング; 回転平膜; スポンジ; 凝集; 沈殿

Effects of coagulation/sedimentation as a pretreatment on the dead-end ultafiltration(UF) membrane was studied in terms of membrane fouling and removal efficiency of natural dissolved organic carbon, using Chitose River water. Two types of experimental runs were carried out. One was bench scale membrane filtration with Jar-test and the other was continuous membrane filtration equipped with jet mixed separator as a unit of coagulation/sedimentation. In the bench scale experiment, effects of coagulant dosage, pH and operating pressure on membrane fouling and removal efficiency of natural dissolved organic matter were investigated. In the continuous membrane filtration experiment, we also investigated the reduction of membrane fouling and the removal efficiency of natural dissolved organic matter. Coagulation/sedimentation prior to membrane filtration process increased the removal efficiency of natural dissolved organic matter and improved the membrane filterability.We investigated the ef … More fects of physical cleaning on the UF membrane fouling in dead-end and outside-inside mode operation under a constant flux. By the air-scrubbing combined with the back washing, the irreversible cake resistance was drastically decreased, comparing with the back washing only. By monitoring the increase in trans-membrane pressure and analyzing the quality of wastewater caused by physical cleaning, it may be explained that the high molecular weight humic substances and suspended particles removed by membrane were effectively lifted and sheared by air-scrubbing. From the experimental results using physical cleaning with different times of air-scrubbing and back washing, and air-scrubbing intensity, it was found that the longer the air-scrubbing and back washing and the stronger the air-scrubbing, the higher the cleaning effect. But there exists the optimum condition of physical cleaning.For the control of membrane fouling and improvement of water quality, ozoneation process was used as a pretreatment of microfiltration(MF). Effect of ozone dosage and residual ozone in MF permeate were investigated in terms of membrane fouling and removal efficiency of organic and inorganic matter. Removal efficiency of humic substances in case of pre-ozonation was 1.5-2.0 times higher compared to the case of direct filtration of Chitose river water. But, the removal of TOC in the case of pre-ozonation was somewhat lower than the case of direct filtration of Chitose river water. In case of ozone oxidation followed by air-scrubbing and ozonation alone, removal efficiency of manganese are about 90 %, 50 %, respectively. AOC in case of pre-ozonation was 2.5-8.2 times higher compared with the case of direct filtration of Chitose river water. Pre-ozonation improved the membrane filterability. Especially, when residual ozone exists in permeate, high permeate flux and low operation pressure were achieved in constant pressure mode and constant flux mode., respectively. The reasons of improved of membrane filterabilty by using pre-ozonation may be considered as follows : Firstly, degradation of high molecular weight organic matter, mainly humic substances. Secondly, the improvement of physical cleaning effect against organic and inorganic matter accumulated in the membrane. Less

使用两种类型的经验河水进行了凝结，以膜和去除效率，对膜和去除效率进行了凝血的影响用jar测试和另一个缩放膜是在基准尺度实验中配备了射流混合分离剂的连续膜。并去除有机物的凝血/粘膜效率空气灌木结合后洗涤，不可逆的蛋糕耐药性大大降低，通过监测跨膜压力的增加并分析由物理清洁引起的eWater质量从膜上取出并通过空气灌溉的结果来取出并剪切。擦洗，高效果，但最佳的物理清洁状况。为了控制膜和改善，臭氧质量，臭氧质量，wass ass ass ass ass ass ass ass ass ass ass ass ass ass ass ass ass ass ass ass ass ass ass ass ass ass ass ass ass ass ass ass wass wass as sicroftration as sicroftrations as Microftrations as Microftrations as Microftrations as was MF在MF渗透中的臭氧和无机物质的稳定性的影响。该案例是壳聚糖河水的案例。在渗透性中存在残留的臭氧，尤其是在恒定的压力模式下实现了较高的渗透和低操作的原因，尤其是膜过滤的方向。臭氧化可以如下：首先，高分子量有机物的降解，主要是腐殖质。