Is it possible to purify ocean water

But what if we could make seawater safer to drink? It turns out that we can and the process is called desalination. Desalination is a process that removes dissolved minerals including but not limited to salt from seawater, brackish water, or treated wastewater. A number of technologies have been developed for desalination, including reverse osmosis RO , distillation, electrodialysis, and vacuum freezing.

So why is seawater such an attractive water resource that we go through all those costly process to make it safe to drink? Here are a few reasons Seawater provides an unlimited, reliable water supply for coastal populations worldwide; brackish water is a plentiful, relatively drought-proof water resource for inland populations and reduces dependency on imported water. And, of all the Earth's water, 97 percent is salt water, only 1 percent is fresh water available for humans to drink, and 2 percent is frozen.

To date, only a limited number of desalination plants have been built along the California coast, primarily because the cost of desalination is generally higher than the costs of other water supply alternatives available in California e. However, as drought conditions occur and concern over water availability increases, desalination projects are being proposed at numerous locations in the state.

Desalination costs are decreasing as technology improves and more plants are built. There is increasing regional scarcity, though. The problem is that the desalination of water requires a lot of energy.

Salt dissolves very easily in water, forming strong chemical bonds, and those bonds are difficult to break. Energy and the technology to desalinate water are both expensive, and this means that desalinating water can be pretty costly.

It's hard to put an exact dollar figure on desalination—this number varies wildly from place to place, based on labor and energy costs, land prices, financial agreements, and even the salt content of the water.

That's about as much as two people in the U. But switch the source to a river or an aquifer , and the cost of a cubic meter of water can plummet to 10 to 20 cents, and farmers often pay far less.

That means it's still almost always cheaper to use local freshwater than to desalinate seawater. This price gap, however, is closing. For example, meeting growing demand by finding a new source of water or by building a new dam in a place like California could cost up to 60 cents per cubic meter of water.

As such, this cost figure is expected to continue to rise, which is why California is now seriously considering desalination and why the city of Tampa, Fla. The International Desalination Association says that as of there were about 13, desalination plants operating around the world.

They pumped out approximately A lot of these plants are in countries like Saudi Arabia, where energy from oil is cheap but water is scarce. There are two basic methods for breaking the bonds in saltwater: thermal distillation and membrane separation. The answer probably depends on where you live.

Given the high costs of freshwater importation and reclamation, desalinating seawater is an increasingly attractive option for water-stressed areas.

The potential for desalination is limited mostly by social, political, environmental and economic considerations, which vary from place to place. Any way you look at it, the rising tide of desalination seems likely to remain a growing part of our water portfolio for years to come.

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Mobile Newsletter chat avatar. Mobile Newsletter chat subscribe. Wilderness Survival. Why can't we convert salt water into drinking water? See pictures of ocean currents. How and where is desalination used today? The Cost of Desalination There's little doubt that the world needs more drinking water. How does reverse osmosis work? How much water is there on Earth?

Gleick, J. Washington DC: Island Press. Gold, M. Special Reference Briefs Series No. SRB Department of Agriculture. Climate Change Impacts, Adaptation and Vulnerability. Cambridge University Press. Vice President, Poseidon Resources. Personal correspondence.