Enhancement of permeate flux by gas slugs for crossflow ultrafiltration in tubular membrane module

Journal Article · Sun Nov 01 04:00:00 EST 1998 · Separation Science and Technology

DOI:https://doi.org/10.1080/01496399808545276· OSTI ID:293019

Cheng, T W; Yeh, H M; Gau, C T ^[1]

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1. Tamkang Univ., Tamsui (Taiwan, Province of China). Dept. of Chemical Engineering

Flux enhancements by gas slugs for dextran T500 solutions ultrafiltrated in a ZrO{sub 2}/carbon tubular membrane module were measured and are discussed for various resistances of the concentration boundary layer. These resistances are functions of the liquid velocity, the transmembrane pressure, and the feed concentration in the liquid-phase ultrafiltration. When the boundary layer resistance is low, the flux enhancement by gas slugs is limited. For a liquid ultrafiltration system with a severe concentration polarization, or operated in conditions of low liquid velocity, high transmembrane pressure, and high feed concentration, flux enhancement by gas slugs is very significant if the gas velocity exceeds a certain threshold. This threshold gas velocity depends on the extent of the concentration polarization in the single liquid-phase ultrafiltration system. It is concluded that the same permeate flux obtained in single liquid-phase ultrafiltration with a higher crossflow velocity can also be achieved with a lower liquid velocity by introducing gas slug of moderate velocity, and lead to reduced energy consumption.

• Sponsoring Organization: USDOE
• OSTI ID: 293019
• Journal Information: Separation Science and Technology, Journal Name: Separation Science and Technology Journal Issue: 15 Vol. 33; ISSN 0149-6395; ISSN SSTEDS
• Country of Publication: United States
• Language: English

Related Subjects

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATION
AUGMENTATION
GAS FLOW
MEMBRANE TRANSPORT
MEMBRANES
SEPARATION PROCESSES
TWO-PHASE FLOW
ULTRAFILTRATION