Future of Water Purification
While putting a glass of brackish, brown water into a machine and getting clear, clean water on the other side seems like something out of a futuristic movie, scientists are closer to that than we think. From desalinating sea water into drinkable water to providing fresh water for places that have never had clean drinking water, science has been working to ensure that everyone has access to good, healthy water.
Each year, 3.5 billion gallons of fresh water are produced by desalination plants. This means that three and a half billion gallons of fresh water are produced by factories that take the salt out of salt water. They get the salt water or brackish water from oceans or from the mouths of rivers, and then use certain processes to rid the water of the salt and impurities that make it impossible for people to drink otherwise.
The two processes used the most often in desalination are reverse osmosis and multistage flash distillation. Reverse osmosis works on the scientific principle that when enough pressure is applied to sea water, the fresh water will pass through a semi-permeable membrane. This is how the water is separated from the salt. Multistage flash distillation occurs when sea water is boiled and piped into a low pressure room where it instantly turns into steam, separating the fresh water from the salt. This is done several times to make sure all the salt is gone.
There are other processes used for desalination as well, though not as frequently because they are expensive. Science is also exploring new ways of desalinization such as freezing the water and rinsing away the salt from between the ice crystals. Most desalinization plants are located in places where there is scarce water, like deserts and islands, and while they are expensive to run, science is getting closer to an answer.
Two years ago, a company based in Switzerland came up with a small, easy to carry, simple to use, electricity and replaceable part-free device that filters water instantly for people to drink for under three dollars. This company produced the LifeStraw, certainly a futuristic idea for the time, but the device does everything stated above.
The LifeStraw uses a system of filters inside a 25 cm long and 2.9 cm wide blue tube with top and bottom caps and a string so the user can wear it around his neck. All the user needs to do is put the bottom end into the water and suck water through to the other end to get the clean water they wish to drink. The LifeStraw lasts for 700 liters of water, or two liters a day for a year, which is the estimated amount of water a person drinks per year.
This miraculous invention has been purchased mostly by aid organizations who then hand them out to people in third world countries who have never had access to drinking water. One sixth of the world�s population has never had clean drinking water, and it leads to deaths from bacterial diseases like dysentery, cholera, and typhoid. But this is slowly being helped with the LifeStraw.
While the Vestergaard Frandsen Group has yet to mass produce the LifeStraw, they are working on a way to make them even more economical. The owner of the company hopes to not only mass produce the LifeStraw, but to get one to every person in countries with bad water, and to replace them every year.
Sono Arsenic Filter
In February of 2007, Abul Hussam, a professor at George Mason University in Fairfax, was awarded the one million dollar prize of the Grainger Challenge Prize from the National Academy of Engineering. Hussam�s million dollar invention was the Sono arsenic filter, a system that was made to filter arsenic out of ground water.
Several years ago, aid agencies unwittingly caused a problem by raising money for programs to dig wells for water in Eastern India and Bangladesh. What the charities didn�t know was that the well water would be tainted heavily with arsenic, and people who had been drinking the water without filtration had been getting sick, shortening the life expectancy to thirty five years from arsenic poisoning.
Hussam invented the Sono arsenic filter, which is being produced for about forty dollars in Bangladesh, with over 30,000 already installed in villages in East India. The filter works by passing the water though porous iron, which has a chemical bond with arsenic, removing almost every trace of the arsenic. Hussam is spending 70% of his prize money to distribute more of his water filters for free, 25% on more research, and 5% is being donated to the George Mason University.
Science is already making leaps and bounds in the world of water purification and filtration, though there is certainly more out there. Desalinization, as well as other forms of filtration, especially for third world countries, is becoming more important as more people die every year from drinking the harsh natural water.