Fouling mitigation for hollow-fiber UF membrane by sonication

Effects of ultrasound parameters on ultrasound-assisted ultrafiltration using cross-flow hollow fiber membrane for Radix astragalus extracts

“…Accordingly, less power is required at low frequency to achieve a desired flux enhancement. Similar effect of ultrasonic power on permeate was reported by Li et al [12] for hollow fiber UF membranes. The finding that lower frequency is more effective on hollow fiber UF membranes is in agreement with what had been observed by Kobayashi et al [17] and Lamminen et al [18] on flat sheet membranes.…”

“…HFM can be broken at a high power ultrasound irradiation. Similar phenomenon has been observed by Li et al [12]. Accordingly, HFM should be used at a condition of not very high ultrasound intensity.…”

“…All those techniques have some limitations. For example, gas sparging is time consuming due to the interruption of operation process for cleaning [12]; electrical techniques used for permeate flux enhancement may induce the electrolysis effect [13].…”

Sonochemical control of fouling formation in membrane ultrafiltration of wastewater: Effect of ultrasonic frequency

“…OM has been characterized through UV 254 [19] which was measured using a dual-beam spectrophotometer (Perkin Elmer, Lambda 12 Model) with a 1 cm quartz cell. The turbidity was measured after each treatment by a Turbidimeter (HACH, Model 2100).…”

“…The high temperatures and pressures generated at the collapsing spots are also a source of • OH radicals, which may produce the oxidation of organic pollutants and molecules at the gas-liquid interface [12,17,18]. Therefore, these sonochemical reactions can degrade through chemical oxidation the organic matter (OM) in water [19] and wastewater [20][21][22][23] as well as decompose chemical compounds and microbial cells [17,[19][20][21][22][23][24][25][26]. Moreover, OM is described as the major foulant type in water treatment [13].…”