SEAWATER DESALINATION -
INEVITABLE TECHNOLOGY OF THE FUTURE
Seawater desalination, the process of purifying saline water, is on the cusp of new technology that is proving to be a reliable solution to freshwater scarcity.Written by: Azam Khan
There is 70% water on the earth's surface, 3% is fresh and drinkable; out of that 3%, 2% belongs to ice caps, underground reservoirs, glaciers, etc. Recent statistics reveal 1 out of 3 people don't have access to clean drinking water. The dwindling sources and the essential need for freshwater have instigated a push for new ways to clean salty ocean water.
THE PROCESS OF DESALINATION
Desalination is a method of cleaning saltwater for human consumption. Currently, there are two types of popular desalination methods: Thermal Desalination and Reverse Osmosis.
Thermal desalination is boiling seawater and creating purified steam; the steam is condensed and collected to produce high-purity water. Reverse osmosis doesn't need heat. It starts with extracting water from wells employed on the shoreline or an intake structure deployed into the ocean. Water pumps through a semi-permeable barrier consisting of polyamide, polysulfone layers, and a polyester base, where freshwater passes through the membrane and the remaining byproduct, brine, is discarded.
PREVENTING A POTENTIAL
The ONLY SOLUTION FOR
Freshwater resources are incredibly scarce and continue to shrink by the day. Our oceans are great water resources, and desalination offers a viable and workable solution to cleaning salty water. If we can bring them into everyday use, we can tackle the issue.
Water scarcity is more of a pressing issue in the Middle East and North Africa; therefore, there is a concentration of desalination plants in these two areas, with around 5000 currently active in that region. One notable mention in this regard is IDWT (International Desalination Water Treatment Group). They were the first to introduce desalination plants in the Sinai Peninsula and are aiming to expand their efforts in these regions.
Desalination is appealing; however, there are few significant concerns. For one, it takes a tremendous amount of energy to break the bond between water and salt and can be 25 times more energy-intensive than other water cleaning approaches. The second concern is its cost intensiveness; beyond the environmental costs to produce the energy needed to power the project, costs of equipment and repairs are also ample.
Furthermore, desalination can be potentially devastating for marine life as it takes extensive amounts of water from ocean reservoirs. It produces a threat by shrinking water reservoir and discharging brine into the ocean, which is a more concentrated salt solution and is doubly baleful for marine life. Globally we are producing 37 billion gallons a day of brine, and there is currently no proper method of handling it. Recent studies reveal for every litre of water we have; we dispose of 1.5 litres of brine.
NEW TECHNOLOGIES ON THE HORIZON
With the drawbacks mentioned above, we continue to use this method for two main reasons. Firstly, it is a trusted purification method known to us, and the water supply of the ocean is enormous. Secondly, with climate change, a growing population and scarce water resources, there is a cause for concern as the depletion of clean water can lead to the spread and transmission of waterborne diseases, environmental and economic decline, and other detrimental matters.
However, scientists are developing a new technology that will make the process more energy-efficient. Capacitive Deionization, also known as CDI, uses electrodes to attract salt ions and uses them to produce electricity. In addition to that, Stanford researchers have developed a method of using brine, instead of discharging it into the ocean, by splitting the sodium and chlorine and forming other chemicals, respectively, made for different industrial usages.
Desalination offers an excellent option to balance the supply and demand of water. However, it is not the ultimate solution but a promising one if the industry can overcome desalination challenges.
With a leading presence in the Middle East and North Africa, the IDWT Group offer comprehensive solutions for a range of water-related issues. Their product catalogue includes essential chemical supply, filtration, water treatment plants, desalination, demineralization, and ZLD.