Ultrasound Assisted Ultrafiltration membrane Cleaning Process
Date Issued
2007
Date
2007
Author(s)
Lin, Shan-Shian
DOI
zh-TW
Abstract
The most concerned issue in membrane filtration process is membrane fouling that causes permeate flux decline, reduces operation period and increases operation cost. In this study, ultrasound (US) assisted filtration and cleaning process was applied for fouling prevention and cleaning in ultrafiltration (UF) systems fouled by humic acid. Low frequency (20 kHz) probe type ultrasound propagated on the top of flat-sheet polyethersulfone (PES) membrane. Flux measurement indicates that US assisted membrane filtration operated at lower pressure and using smaller MWCO of membrane were effective for recovery of flux decline due to fouling.
Ultrasound assisted cleaning (UAC) process was applied in pulse mode. After fouling by humic acid,using different MWCO of fouled membranes treated in UAC process respectively. The results show that UAC process achieved high flux recovery (96~99 %), particularly for smaller MWCO of membrane. The data results suggest cavitation bubbles collapse phenomena, which can easily ensues fragmentation or abrasion on surface fouling. Operation was re-iterated 4 times on membrane reuse experiment, which performed in terms of quantity (flux recovery) and quality (TOC rejection rate). The result was barely changing in quantity and quality. Operating at high pressure, some damages were observed by SEM images. However, no damage to the membrane was observed.
Subjects
超音波輔助清洗程序
超濾薄膜
氣穴現象
間歇式操作
Ultrasound assisted cleaning process
Ultrafiltration
Cavitation
Type
thesis