As you read this, fresh water scarcity is causing some serious problems to more than a billion people around the world. But a major chunk of these people are based in arid developing countries. According to World Health Organization 750 million people around the world lack access to safe pure drinking water. This is approximately one in nine people. More than twice the population of the United States lives without access to safe water, making the current water crisis the #1 global risk, based on impact to society (as a measure of devastation), and the #8 global risk, based on likelihood (likelihood of occurring within 10 years) as announced by the World Economic Forum, January 2015.
The World Health Organization predicts that by mid-century, four billion, almost two-thirds of the world’s current population, will face severe fresh water shortages.
With human population expected to rise by another 50 percent by 2050, resource managers are increasingly looking toward alternative scenarios for quenching the world’s growing thirst. Desalination, a process through which highly pressurized ocean water or seawater is pushed through tiny membrane filters and distilled into drinking water, is being held forth by some as one of the most promising solutions to the problem.
Think about it – 71% of the earth is covered by oceans so why don’t we use ocean water to solve the water problems that we keep talking about?Removing salt from water, especially seawater in coastal communities is a viable option for solving water issues.
Desalination is the process used to remove salt and minerals from seawater or brackish water. At the moment, there are two popular technologies used for desalination process.
The first more popular technology is called membrane technology or reverse osmosis. It’s a process that uses pressure to force water through a membrane that does not allow the salt particles to pass. In some cases, instead of using pressure to drive the water through the membrane, electricity is used.
The second technology, uses a thermal process, when salt water is heated and that produces vapor, which is then condensed and collected as fresh water. It is very similar to the evaporation process of ocean water and explains why rain water is not salty.
This brings us to the very fact that desalination of salt water could provide an unlimited supply of water to the entire world’s population. And as the demand for water and the population increases, seawater desalination could provide a source of water that can meet those new demands consistently.
Contrary to popular belief that desalination is very expensive, the truth is that the costs of desalination are becoming more affordable, and the quality of the permeate produced water has been improved tremendously. One cost-effective example is an installation of a desalination plant in Singapore. In its first year of operation in 2013, the cost of desalinating water was as low as USD 0.45 per cubic meter. Combining this with the availability of water makes desalination an attractive proposition for many of us around the world.
Today, seawater desalination plants are used to convert sea water to drinking water on ships and in many arid regions of the world, and to treat water in other areas that is contaminated by natural and unnatural contaminants.
Distillation is perhaps the one water treatment technology that completely reduces the widest range of drinking water contaminants. Speaking of which, the impact of desalination is significant. In 2012, the installed global capacity for desalination totaled 27.3 cubic kilometers of generated fresh water annually. About 60% of desalination capacity treats seawater, and the rest treats other, less saline sources.
In 2014, this capacity has increased from 17.4 cubic kilometers compared to five years earlier, which essentially means that it’s been growing at an average annual rate of 9.5%.
As for desalination equipment, organizations such as Ampac USAdesign and manufacture advanced seawater desalination fresh watermakers for onshore and offshore applications. Onshore watermakers are designed for land-based applications; these seawater desalination watermakers can be fed directly from the sea or from any beach well, and convert seawater to pure fresh drinking water, which make them suitable for locations with no fresh or municipal water supplies such as remote areas, or smaller atolls and islands having no potable water sources. On the other hand, marine off-shore watermakers suit most type of boats, yachts, and military ships.
In addition, they also design and manufacture off-shore Class1-Div1 and Class1-Div2 Explosion Proof Seawater Desalination Watermakers for the oil and gas industry, as well as Emergency Portable Fresh Watermakers, and Solar Powered Brackish Water and Seawater Desalination Watermakers.
Currently, there are some large desalination plants under construction in the US. When the Carlsbad Desalination Project is completed this fall, it will be the largest desalination plant in the Western Hemisphere.This largest seawater desalination plant, a $1 billion state-of-the-art reverse osmosis, is set to begin producing 54 million gallons a day, supplying water to 300,000 residents, in early 2016.
Over 17,000 desalination plants are now operating in 150 countries worldwide, a capacity that could nearly double by 2020, according to the United Nations World Water Development Report 2014. Desalination produces 21 billion gallons of water a day, according to the International Desalination Association, providing a crucial water source in arid places such as the Middle East and Australia.