Effects of various frequencies and powers of ultrasound on cleaning of flat sheet membrane during and after microfiltration

Abstract

A B S T R A C TMembrane processing has found many applications in various industries as an advanced method of separating materials in liquid or gas. The greatest obstacle in using membrane filtration technology is fouling, particularly in porous membranes. The fouling phenomenon is the result of organic and inorganic materials depositing on the surface and pores of membrane. In this study, the effect of ultrasound frequency (37, 80 kHz, and tandem) and amplitude of sonication (30, 60, and 90%) were evaluated on flux recovery during and after microfiltration. Results showed that the 37 kHz and tandem frequencies significantly improved the permeate flux at earlier minutes, particularly when tandem frequency was applied. In addition, the permeate flux was increased as the sonication power increased. However, the interaction effects between frequency and sonication power showed that the ultrasound frequencies were more effective than sonication power on flux recovery. Furthermore, the calculation of fouling percentage showed that both low frequencies and high amplitude together significantly reduced the fouling agents during the cleaning process. However, there were no remarkable statistical effects among the same levels of sonication power during the cleaning process. The interaction effects of various frequencies and powers of ultrasound on cleaning membranes were evaluated and more cleaning efficiency was observed in comparison to sonication power when low frequency applied.

Hollow Fibers Filtration and Cleaning Processes Under Ultrasound and Gas Bubbling Combination

“…Maskooki et al . () obtained similar results in cleaning of flat sheet membrane by ultrasonic waves. They reported that ultrasound irradiation causes to a significant improvement in flux recovery during cleaning of fouled membranes.…”

“…Evaluating the cleaning effects of ultrasound (US) and gas bubbling (GB) treatments on fouled membranes, forward flushing was performed using deionized water under the US and GB treatments for 30 min (Maskooki et al . ).…”

“…; Maskooki et al . ). Generally, the source power of ultrasound with low frequencies and high intensities are used in the range of 20–100 kHz, and up to 1,500 W, respectively.…”

Ultrafiltration of Cherry Concentrate Under Ultrasound with Carbonated Feed as a New Fouling Control Method

“…; Maskooki et al . ). The effect of the US ‐assisted is based on detaching the foulants by cavitation and microstream mechanisms (Li et al .…”

“…The use of low frequencies of US has been studied as an alternate technology for enhancing permeation flux in filtration processes. US can be used either during the filtration to enhance the permeation or as a cleaning technique to improve the cleaning efficiency (Kyll€ onen et al 2005;Muthukumaran et al 2006;Maskooki et al 2015). The effect of the US -assisted is based on detaching the foulants by cavitation and microstream mechanisms (Li et al 2002;Kobayashi et al 2003;Lamminen et al 2004).…”