Energy Efficient Forward Osmosis to Maximize Dewatering Rates

Area of Science:

• Membrane Science and Technology
• Chemical Engineering
• Water Treatment Technologies

Background:

• Forward osmosis (FO) is an energy-efficient dewatering process driven by osmotic pressure.
• Conventional FO systems face performance limitations due to draw solution dilution and feed solution concentration.
• Addressing these limitations is crucial for enhancing FO's industrial applicability.

Purpose of the Study:

• To propose and evaluate a novel hybrid FO module configuration.
• To improve the osmotic driving force and overall performance of FO systems.
• To reduce energy consumption in FO-based concentration and resource recovery.

Main Methods:

• Development of a hybrid FO module with series-flow feed solution and parallel-flow draw solution.
• Utilizing an experimentally validated FO module model for simulations.
• Employing reverse osmosis (RO) simulation tools for comparative analysis.

Main Results:

• The proposed draw solution split distribution (DSSD) achieved an enrichment ratio of 12.5.
• DSSD demonstrated reduced energy consumption of 0.137 kWh/m³ compared to conventional FO.
• The DSSD configuration outperformed conventional FO and matched RO performance at significantly lower energy costs.

Conclusions:

• The novel DSSD configuration offers superior dewatering capacity and energy efficiency.
• This hybrid FO approach presents a promising solution for industrial concentration and resource recovery.
• Potential applications include food processing, beverage production, pharmaceuticals, and agriculture.