Reverse osmosis (RO) is a compact process that has potential for the removal of ionic and organic pollutants for recycling space mission wastewater. Seven candidate RO membranes were compared using a batch stirred cell to determine the membrane flux and the solute rejection for synthetic space mission wastewaters. Even though the urea molecule is larger than ions such as Na+, Cl-, and NH4+, the...

Enhancement of the performance of a reverse osmosis (RO) unit through periodic control is studied. The periodic control manipulates the feed pressure and flow rate of the RO unit. To ensure the periodic behavior of the inputs, the manipulated variables (MV) are transformed into the form of sinusoidal functions. In this case, the amplitude and period of the sinusoidal functions become the surrog...

? Transport proteins play a critical part in solute movement because membranes constitute a barrier to free diffusion of molecules. If membranes allowed rapid diffusion of both ions and water, gradients of ions would be slight and osmotic pressure could only be achieved with enormous energy consumption. Instead, some molecules, such as water and gases, move rapidly across membranes. Unrestricte...

Forward osmosis (FO) is a promising membrane technology to combine seawater desalination and water reuse. More specifically, in a FO-reverse osmosis (RO) hybrid process, high quality water recovered from the wastewater stream is used to dilute seawater before RO treatment. As such, lower desalination energy needs and/or water augmentation can be obtained while delivering safe water for direct p...

Service experience from 27 seawater reverse osmosis (SWRO) plants confirms that there is an evident risk of corrosion if wrong steel grade is used for the high pressure piping. Neither 316L nor 317L possesses sufficient corrosion resistance. Not even highly alloyed grades like 2205 and 904L show reliable service performance. However, no corrosion has been reported for 254 SMO, which has been us...

Biology student mastery regarding the mechanisms of diffusion and osmosis is difficult to achieve. To monitor comprehension of these processes among students at a large public university, we developed and validated an 18-item Osmosis and Diffusion Conceptual Assessment (ODCA). This assessment includes two-tiered items, some adopted or modified from the previously published Diffusion and Osmosis...

A novel osmotic membrane bioreactor (OsMBR) is presented. The system utilizes a submerged forward osmosis (FO) membrane module inside a bioreactor. Through osmosis, water is transported from the mixed liquor across a semi-permeable membrane, and into a draw solution (DS) with a higher osmotic pressure. To produce potable water, the diluted DS is treated in a reverse osmosis (RO) unit; the by-pr...

Desalination that produces clean freshwater from seawater holds the promise of solving the global water shortage for drinking, agriculture and industry. However, conventional desalination technologies such as reverse osmosis and thermal distillation involve large amounts of energy consumption, and the semipermeable membranes widely used in reverse osmosis face the challenge to provide a high th...

The conversion of saltwater and brackish water into fresh through desalination has gained significant importance as a solution to the worldwide scarcity resources. Reverse Osmosis (RO) method been effectively utilized generate from sources water. This research aims examine variables that affect performance reverse osmosis process. effectiveness membrane was assessed experiments explored impact ...