Exploring the Operation Factors that Influence Performance of a Spiral-Wound Forward Osmosis Membrane Process for Scale-up Design

Abstract

Forward osmosis (FO) technology has increasingly attracted attention owing to its low operational energy and low fouling propensity. Despite extensive investigations on FO, very few module-scale FO studies on the operation and design of the FO process have been conducted. In this paper, a simple and practical FO process design parameter called normalized membrane area is suggested based on a performance analysis of spiral-wound FO elements. The influence of operation factors on operating pressures and water recovery was investigated using 8-inch spiral wound elements in the continuous operation mode. The membrane area was adjusted by series connection of FO elements to a maximum value of 46 m2 (three elements). The feed and draw flow rates were varied between 5 and 15 LPM under various feed (10, 20, and 30 g/L) and draw (58.4 and 233.8 g/L) concentration combinations. The analysis of flow rates (feed, draw, and permeate flow rates) indicated not only high flow channel resistance on the draw side but also high permeate flow rates can induce higher operating pressures owing to strong mutual interaction of the feed and the draw streams. Feed water recovery was focused on as a key performance index, and the experimental recovery (RExp) and theoretical maximum recovery (RTh) values were compared. The results revealed the significance of the feed flow rate and the membrane area in terms of enhancing the water recovery performance. In addition, a clear relationship was observed between the membrane area normalized by the initial feed flow rates and the water recovery ratio (RExp/RTh), even though the applied operation conditions were different. Finally, an empirical equation to estimate the required membrane area of spiral-wound FO was proposed for the FO process design. The equation can be used to predict water recovery of FO systems as well, for example, if an FO system is operated at 0.08 m2L−1h of the normalized membrane area, the system is expected to offer 78% of the RTh value.

Economic Analysis of Membrane-Based Separation of Biocatalyst: Mode of Operation and Stage Configuration

“…In this case, at a fixed membrane area, the amount of permeate falls as the flux declines. So, to obtain the targeted permeation, the unit operation has to be designed for the plateaued rather than initial flux in order to provide for sufficient membrane area. , …”

“…So, to obtain the targeted permeation, the unit operation has to be designed for the plateaued rather than initial flux in order to provide for sufficient membrane area. 53,54 2.5. Effect of Stage Configuration on the Cost Components.…”

Performance Comparison of Spiral-Wound and Plate-and-Frame Forward Osmosis Membrane Module

“…Two pilot-scale FO systems were adopted for investigating SW FO and PF FO membranes. The schematic diagram and details about the FO systems are provided in our previous study [15,22]. Briefly, the FO systems were equipped with magnetic flow meters, digital pressure gauges, and conductivity meters at the inlet and outlet of FS and DS sides, and the online data were recorded using a connected computer.…”

Effect of Flowrate and Pressure on the Crossflow Filtration in Textile Wastewater Treatment by Commercial UF Membrane

“…According to the Malaysian Department of IOP Publishing doi:10.1088/1755-1315/1303/1/012022 2 Statistics, the textile industry contributed 0.5% to the country's GDP growth in 2022, with a compound annual growth rate (CAGR) of 4.2% [2]. Currently, Malaysia has over 662 factories engaged in textile manufacturing and finishing [3,4].…”