Columbia Engineering researchers design new desalination method for hypersaline brines that is low-cost, efficient, and effective; could address the growing water challenges across the globe.
Hypersaline brines–water that contains high concentrations of dissolved salts and whose saline levels are higher than ocean water–are a growing environmental concern around the world. Very challenging and costly to treat, they result from water produced during oil and gas production, inland desalination concentrate, landfill leachate (a major problem for municipal solid waste landfills), flue gas desulfurization wastewater from fossil-fuel power plants, and effluent from industrial processes.
If hypersaline brines are improperly managed, they can pollute both surface and groundwater resources. But if there were a simple, inexpensive way to desalinate the brines, vast quantities of water would be available for all kinds of uses, from agriculture to industrial applications, and possibly even for human consumption.
A Columbia Engineering team led by Ngai Yin Yip, assistant professor of earth and environmental engineering, reports that they have developed a radically different desalination approach–“temperature swing solvent extraction (TSSE)”–for hypersaline brines. The study, published online in Environmental Science & Technology Letters, demonstrates that TSSE can desalinate very high-salinity brines, up to seven times the concentration of seawater. This is a good deal more than reverse osmosis, the gold-standard for seawater desalination, and can hold handle approximately twice seawater salt concentrations.
Currently, hypersaline brines are desalinated either by membrane (reverse osmosis) or water evaporation (distillation). Each approach has limitations. Reverse osmosis methods are ineffective for high-saline brines because the pressures applied in reverse osmosis scale with the amount of salt: hypersaline brines require prohibitively high pressurizations. Distillation techniques, which evaporate the brine, are very energy-intensive.
Yip has been working on solvent extraction, a separation method widely employed for chemical engineering processes. The relatively inexpensive, simple, and effective separation technique is used in a wide range of industries, including production of fine organic compounds, purification of natural products, and extraction of valuable metal complexes.
“I thought solvent extraction could be a good alternative desalination approach that is radically different from conventional methods because it is membrane-less and not based on evaporative phase-change,” Yip says. “Our results show that TSSE could be a disruptive technology–it’s effective, efficient, scalable, and can be sustainably powered.”
TSSE utilizes a low-polarity solvent with temperature-dependent water solubility for the selective extraction of water over salt from saline feeds. Because it is membrane-less and not based on evaporation of water, it can sidestep the technical constraints that limit the more traditional methods. Importantly, TSSE is powered by low-grade heat (< 70 C) that is inexpensive and sometimes even free. In the study, TSSE removed up to 98.4% of the salt, which is comparable to reverse osmosis, the gold standard for seawater desalination. The findings also demonstrated high water recovery >50% for the hypersaline brines, also comparable to current seawater desalination operations. But, unlike TSSE, reverse osmosis cannot handle hypersaline brines.
“We think TSSE will be transformational for the water industry,” he adds. “It can displace the prevailing practice of costly distillation for desalination of high-salinity brines and tackle higher salinities that RO cannot handle,” Yip adds. “This will radically improve the sustainability in the treatment of produced water, inland desalination concentrate, landfill leachate, and other hypersaline streams of emerging importance. We can eliminate the pollution problems from these brines and create cleaner, more useable water for our planet.”
Yip’s TSSE approach has a clear path to commercialization. The heat input can be sustainably supplied by low-grade thermal sources such as industrial waste heat, shallow-well geothermal, and low-concentration solar collectors. He is now working on further refining how TSSE works as a desalination method so that he can engineer further improvements in performance and test it with real-world samples in the field.
The Latest on: Desalination
via Google News
The Latest on: Desalination
- Antioch Desalination Plant: City Takes Out $15M Line Of Crediton November 28, 2020 at 2:31 am
Once construction starts on the Antioch Brackish Water Desalination Project, it should take two years to complete.
- Seawater Desalination Equipment Market Size 2020: Global Analysis, Industry Growth, Current Trends and Forecast till 2025on November 26, 2020 at 5:46 pm
Market Demand, Growth, Opportunities, Manufacturers and Analysis of Top Key Players to 2025" To Its Research Database. The global water desalination equipment market size is anticipated to reach USD ...
- City Council Approves Signing Of Credit Line For Desalination Projecton November 26, 2020 at 7:55 am
The Antioch City Council on Tuesday night approved signing a new $15 million line of credit for the construction of a desalination plant to treat brackish water drawn from the San Joaquin River.
- Beer maker backs India solar desalination plant to boost water, jobs for womenon November 26, 2020 at 5:18 am
(Thomson Reuters Foundation) - A water desalination plant powered by solar energy in a small east Indian town, backed by beer maker Carlsberg Group, could be a sustainable option for other coastal ...
- What are Desalination plants?on November 25, 2020 at 4:33 pm
On 23 November 2020, Uddhav Thackeray led Maharashtra Government gave a go-ahead to the Brihanmumbai Municipal Corporation (BMC) for setting up of a desalination plant in Mumbai's Manori to ...
- $15 million credit line will help Antioch build desalination planton November 25, 2020 at 10:00 am
Antioch’s plan to build a desalination plant to clear up the city’s brackish water got another boost this week when the City Council unanimously approved $15 million in interim financing.
- $15 million credit line will help Antioch build desalination planton November 25, 2020 at 7:58 am
Antioch’s plan to build a desalination plant to clear up the city’s brackish water got another boost this week when the City Council unanimously approved $15 million in interim financing. The almost ...
- Mumbai: Desalination to ease water stress, raise green concernson November 25, 2020 at 7:51 am
Mumbai's water need is now 4,200 MLD (million litres per day), expected to rise by 71% by 2041 MUMBAI: The state government has green-lighted a desalination plant at Manori to meet the city's ...
- Global Desalination Pumps Market 2020-2024: Size, Share, Emerging Trends, Demand, Revenue and Forecasts Researchon November 23, 2020 at 6:55 pm
Global “Desalination Pumps Market ” report presents a complete overview, market shares, and growth opportunities of ...
via Bing News