Water desalination and wastewater reuse using integrated reverse osmosis and forward osmosis system

Polymeric reverse osmosis (RO) and forward osmosis (FO) membranes have been predominantly used in membrane applications for water desalination. The membrane science has advanced in the past decades and various efforts have been employed to improve the membrane characteristics for enhanced water flux and impurities rejection capability. In this chapter, the progress of RO and FO membranes has been discussed in three sections: synthesis methods of RO and FO membranes, modification works done on the membranes and the formulation used for the synthesis of RO and FO membranes, with particular interest given to the incorporation of nanoparticles in the synthesis of thin film composite membrane.

Download Full-text

Structural investigation and application of Tween 80-choline chloride self-assemblies as osmotic agent for water desalination

Scientific Reports ◽

10.1038/s41598-021-96199-6 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Yasamin Bide ◽

Marzieh Arab Fashapoyeh ◽

Soheila Shokrollahzadeh

Keyword(s):

Nonionic Surfactant ◽

Choline Chloride ◽

Water Flux ◽

Forward Osmosis ◽

Tween 80 ◽

Average Diameter ◽

Feed Solution ◽

Water Desalination ◽

Draw Solution ◽

Osmotic Agent

AbstractForward osmosis (FO) process has been extensively considered as a potential technology that could minimize the problems of traditional water desalination processes. Finding an appropriate osmotic agent is an important concern in the FO process. For the first time, a nonionic surfactant-based draw solution was introduced using self-assemblies of Tween 80 and choline chloride. The addition of choline chloride to Tween 80 led to micelles formation with an average diameter of 11.03 nm. The 1H NMR spectra exhibited that all groups of Tween 80 were interacted with choline chloride by hydrogen bond and Van der Waals’ force. The influence of adding choline chloride to Tween 80 and the micellization on its osmotic activity was investigated. Despite the less activity of single components, the average water flux of 14.29 L m‒2 h‒1 was obtained using 0.15 M of Tween 80-choline chloride self-assembly as draw solution in the FO process with DI water feed solution. Moreover, various concentrations of NaCl aqueous solutions were examined as feed solution. This report proposed a possible preparation of nonionic surfactant-based draw solutions using choline chloride additive with enhanced osmotic activities that can establish an innovative field of study in water desalination by the FO process.

Download Full-text

Using Reverse Osmosis Membrane at High Temperature for Water Recovery and Regeneration from Thermo-Responsive Ionic Liquid-Based Draw Solution for Efficient Forward Osmosis

Membranes ◽

10.3390/membranes11080588 ◽

2021 ◽

Vol 11 (8) ◽

pp. 588

Author(s):

Eiji Kamio ◽

Hiroki Kurisu ◽

Tomoki Takahashi ◽

Atsushi Matsuoka ◽

Tomohisa Yoshioka ◽

...

Keyword(s):

Ionic Liquid ◽

High Temperature ◽

Energy Saving ◽

Osmotic Pressure ◽

Reverse Osmosis ◽

Forward Osmosis ◽

Solution Temperature ◽

Water Recovery ◽

Temperature Dependent ◽

Draw Solution

Forward osmosis (FO) membrane process is expected to realize energy-saving seawater desalination. To this end, energy-saving water recovery from a draw solution (DS) and effective DS regeneration are essential. Recently, thermo-responsive DSs have been developed to realize energy-saving water recovery and DS regeneration. We previously reported that high-temperature reverse osmosis (RO) treatment was effective in recovering water from a thermo-responsive ionic liquid (IL)-based DS. In this study, to confirm the advantages of the high-temperature RO operation, thermo-sensitive IL-based DS was treated by an RO membrane at temperatures higher than the lower critical solution temperature (LCST) of the DS. Tetrabutylammonium 2,4,6-trimethylbenznenesulfonate ([N4444][TMBS]) with an LCST of 58 °C was used as the DS. The high-temperature RO treatment was conducted at 60 °C above the LCST using the [N4444][TMBS]-based DS-lean phase after phase separation. Because the [N4444][TMBS]-based DS has a significantly temperature-dependent osmotic pressure, the DS-lean phase can be concentrated to an osmotic pressure higher than that of seawater at room temperature (20 °C). In addition, water can be effectively recovered from the DS-lean phase until the DS concentration increased to 40 wt%, and the final DS concentration reached 70 wt%. From the results, the advantages of RO treatment of the thermo-responsive DS at temperatures higher than the LCST were confirmed.

Download Full-text

Study of the Ecological Footprint and Carbon Footprint in a Reverse Osmosis Sea Water Desalination Plant

Membranes ◽

10.3390/membranes11060377 ◽

2021 ◽

Vol 11 (6) ◽

pp. 377

Author(s):

Federico Leon ◽

Alejandro Ramos-Martin ◽

Sebastian Ovidio Perez-Baez

Keyword(s):

Reverse Osmosis ◽

Canary Islands ◽

Ecological Footprint ◽

Sea Water ◽

Water Desalination ◽

Energy Costs ◽

Generation System ◽

Negative Part ◽

Desalination Plant ◽

Materials Used

The water situation in the Canary Islands has been a historical problem that has been sought to be solved in various ways. After years of work, efforts have focused on desalination of seawater to provide safe water mainly to citizens, agriculture, and tourism. Due to the high demand in the Islands, the Canary Islands was a pioneering place in the world in desalination issues, allowing the improvement of the techniques and materials used. There are a wide variety of technologies for desalination water, but nowadays the most used is reverse osmosis. Desalination has a negative part, the energy costs of producing desalinated water are high. To this we add the peculiarities of the electricity generation system in the Canary Islands, which generates more emissions per unit of energy produced compared to the peninsular generation system. In this study we have selected a desalination plant located on the island of Tenerife, specifically in the municipality of Granadilla de Abona, and once its technical characteristics have been known, the ecological footprint has been calculated. To do this we have had to perform some calculations such as the capacity to fix carbon dioxide per hectare in the Canary Islands, as well as the total calculation of the emissions produced in the generation of energy to feed the desalination plant.

Download Full-text