26 Mar Would you Drink Seawater?
Most of Earth is made up of water. Seawater that is. Seawater this is undrinkable. It’s crazy to think how much water is on Earth, yet, it’s undrinkable for those who need it the most. Sometimes it’s a cruel irony and this situation is just that.
People have been trying to remove salt from seawater for more than 65 years. The process to remove this salt is called desalination, and today almost 20,000 facilities across the world are making salt water drinkable to sustain growing population number. Sounds great and all, but this process is under major scrutiny because of the potential harm to marine environments and contribution to global warming. Is desalination worth it?
What About Desalination?
Desalination begins with boiling seawater and recovering droplets of fresh water in a process known as thermal desalination. Cleaner, more energy-efficient technologies such as reverse osmosis have become more prevalent. The big exception is the Middle East, where countries rely on fossil fuel-based thermal plants for two-thirds of their desalination needs. The region accounts for roughly 90 percent of thermal treatment of seawater worldwide, according to the International Energy Agency.
Since 2015, about 20,000 desalination plants had a combined production capacity of 86.55 million cubic meters a day. This is roughly 1 percent of the world’s need. Saudi Arabia produces the biggest share of desalinated water, followed by the U.S., the United Arab Emirates, China, Spain and Kuwait, according to the International Desalination Association (IDA).
With the positives from above come negatives. Early criticism focused on the super-heated effluent that many thermal plants discharged back into the sea and how it could kill corals and other marine life. The IDA says desalination facilities now cool this bilge so that it no longer poses such a threat. Another environmental concern centers around the use of fossil fuels to power desalination. A study published in January ignited controversy about “toxic chemicals” in the brine that desalination plants pour into oceans.
The brine may contain harmful residues from anti-scaling and anti-fouling chemicals used in the plants, according to the study by the Hamilton, Canada-based UN Institute for Water, Environment and Health. Desalination creates enough of the pollutant each year to cover the whole state of Florida with 1 foot of brine. Brine can also deplete water oxygen, suffocating marine organisms and disrupting food chains.
Many wonder if desalination can be completed without causing harm to the oceans and environment. It can possibly be done with wider adoption of membrane technologies. This looks like the best way to reduce brine.
Time will tell if the solvent covering 71 percent of the Earth’s surface will be safe to drink in the years to come.