Systems Providing Drinkable Ocean Water
Experts expect that 50 percent of the world population will live in areas with water shortages by 2025. For cities in South Africa, India and China, this crisis is already becoming a reality. So what solutions are there for the shortage of this valuable resource? Water filtration systems and desalination are a few, although many water treatment solutions have not been environmentally friendly and desalination has proven to be costly. However, a lot has changed in water treatment over the years. Here are a few improvements and advancements that could prove promising for the future of potable water, including drinkable ocean water.
Water Softeners and Filtration Systems
Water softeners and filtration systems have gained a negative reputation due to the salt they use and the wastewater they produce that ends up in aquatic environments. However, advancements in these areas have led to softeners that use salt more efficiently and newer equipment reducing water usage and conserving that precious resource. New technology has decreased the usage of both water and salt by 50 percent.
Manufacturers have established ways to achieve high efficiencies by focusing on providing products that are better-performing and able to dictate the amount of water they use during maintenance functions, as well as making larger filtration cartridges that extend the replacement cycle times. Manufacturers have even designed new technology to monitor water usage in the home and adjust to match the household’s habits.
A top priority of the water treatment industry is to develop ways to address contamination while maintaining sustainability. The improvements that manufacturers are making to reverse osmosis (R.O.) systems reflect that.
R.O. systems can result in a reduction of the purchase of bottled water due to how greatly they diminish contaminants. However, the systems still have room for improvement due to the amount of wastewater they produce. The technology to reduce wastewater exists internationally and now the U.S. is looking to make the same progress.
Desalination
If people could drink from the ocean, there would be more than enough water for everyone. However, it would be necessary to remove the salt first.
There are about 2.2 billion people who do not have access to clean drinking water. For thousands of years, turning seawater into drinking water has been an option for this ongoing problem, although the process tends to be expensive and inefficient because it requires a lot of energy.
Kamalesh Sirkar, a chemical engineering professor at the New Jersey Institute of Technology, has a new process that promises to make a difference. His direct-contact membrane distillation (DCMD) system heats seawater across a plastic membrane containing tubes filled with cold distilled water. The tubes have pores so that the water vapor that collects on them can penetrate into them, but not salt. The vapor can then condense back into liquid water.
This efficient system can produce 21 gallons of drinking water per 26 gallons of seawater, which is twice as much as most existing desalination technology. The downside of DCMD is the requirement of a heat source to prevent the water temperature on either side of the membrane from equalizing, although there is the potential of recycling waste heat to run the system.
A team of international scientists has achieved a similar accomplishment by using the sun to produce high-quality potable water. This process can meet the needs of an entire family at a cost of about $100 without using electricity. This team, consisting of scientists from MIT in the U.S. and Shanghai Jiao Tong University in China, believes that its system can provide water to islands and coastal areas that do not have reliable electricity but have access to seawater. With this system, the team produced 1.5 gallons of fresh drinking water every hour for every square meter of the solar collecting area.
GivePower
Recently in Kenya, a nonprofit called GivePower has been able to successfully use solar power to create drinkable ocean water. In July 2018, a new desalination system began operations on the coast of Kiunga that can create 19,800 gallons of drinking water every day. That is enough for 25,000 people. This nonprofit’s main focus has been to provide solar-energy systems to developing countries. The organization has installed solar grids in 2,650 locations across 17 countries in places like schools, medical clinics and villages.
The success of this system is in finding a way to pull water out of the ocean in a scalable, sustainable way. The president of GivePower, Hayes Barnard, hopes to open similar facilities around the world, providing fresh water to people who struggle to get it on a daily basis.
At the rate that the population has been increasing, a freshwater crisis appears imminent. However, with the work that experts are putting into finding a solution, the possibilities for the future look bright. With environmentally friendly filtration systems and the successful production of drinkable ocean water, the population will all be able to drink deeply since there will be enough to go around.
– Janice Athill
Photo: Flickr