By forcing salt water against polymer membranes that trap salt ions and allow fresh water through, reverse osmosis (RO) desalination is an effective water treatment technique. It is relatively expensive, however, due to the energy used to push water molecules through the membrane. But a remarkable facility in Israel, is demonstrating that desalination may be an increasingly practical and cost-effective solution to water security.
The Sorek Desalination Facility, a mega-scale plant built for the Israeli government by Israel Desalination Enterprises (IDE), incorporates engineering improvements that make it more efficient than previous RO facilities. It is the first large desalination plant to use pressure tubes that are 16 inches in diameter rather than eight inches. Therefore, it needs less space and only a fourth of the piping and hardware of a traditional plant, reducing costs. The facility also utilizes a novel pressure center design, double-line intake, and proprietary energy recovery system designed by IDE for increased efficiency and reduced energy consumption. In fact, today its energy consumption is among the lowest in the world for large-scale desalination plants.
“This is indeed the cheapest water from seawater desalination produced in the world,” Raphael Semiat, a chemical engineer and desalination expert at the Israel Institute of Technology told the MIT Tech Review. Sorek sells water to the Israeli water authority for 58 cents per cubic meter, which is a lower price than that offered by most conventional desalination plants. The plant produces 627,000 cubic meters of water daily.
Desalination technology seems to be amidst a current of technological improvement. Specialists believe that sensor-driven optimization, new types of atom-thick membranes, and energy efficient pumps may soon allow desalination plants to be half the size of traditional plants and use dramatically less energy.
There has also been a concurrent surge in deployments. India, Egypt, South Africa, and Mexico have recently dedicated increased funding for plant development.
Stateside, drought-threatened states like California have invested in a number of desalination facilities. In fact, we’ve been drinking desalinated water at Water Efficiency magazine’s headquarters in Santa Barbara, California since May 29th, when the Charles E. Meyer Desalination Plant was recommissioned. While you’d be hard pressed to find anyone that’s even noticed the shift in the city’s water sources, I for one think it tastes like the future.
What are your thoughts: Is RO desalination a feasible solution to water scarcity?
