Pure and safe drinking water is vital for human health. That is why a range of technologies are used to treat drinking water for consumption. What many people don’t know is that the common methods are only good at removing impurities, and they are very ineffective in eliminating the life threatening viruses and bacteria. This is a cause of concern as more and more people are falling to water borne diseases. This is after they have applied the best water treatment methods. This is why; water purification through reverse osmosis holds such potential and promise. This technology is widely used in bottled water, as it is very effective in removing the impurities, thus giving it a very pleasant taste. However, nowadays, reverse osmosis water purification is creeping into households as specially made reverse osmosis water filters are flooding the markets. The main principle behind reverse osmosis is the use of a permeable membrane to block all solute on one side leaving the solvent to pass to the other side. This results in water that is pure and safe. If you are looking towards investing in such a water filter then go through the article below for information on reverse osmosis water purification.
Reverse Osmosis Water Purification
- In this process, semipermeable membranes are used to demineralize the water.
- The water is forced at high pressure through a membrane. This membrane contains pores that are big enough to allow only small molecules to pass through. As such, it is very effective in eliminating a wide range of contaminants.
- The membrane has pores of approximately 0.0005 micron size and so it can remove many bacteria and viruses.
- Two types of membranes are used in reverse osmosis water purification. One is the Thin Film Composite (TFC) and the other Cellulose Triacetate (CTA).
- TFC filters have a higher filtration rate than CTA filters.
- However, TFC filters are more susceptible to degradation by chlorine while CTA membranes start rotting if not protected by chlorine. So, the filters using CTA membranes require a carbon post-filter to remove the chlorine from the purified water.
The Reverse Osmosis Filtration System
- The system is composed of an array of Granular Activated Carbon (GAC) pre-filters and the reverse osmosis membrane.
- It can also contain a storage tank and a faucet to deliver the water for collection.
- The filtration system consists first of a sediment filter. The basic function of this filter is to trap rust and calcium carbonate.
- The next layer is also a sediment filter but with much smaller pores.
- The third layer is the activated carbon filter. This filter traps the organic chemicals and chlorine.
- After the third layer, reverse osmosis (RO) filters are present which are either of TFM or of CTA.
- A second carbon filter can be placed to remove those chemicals that couldn’t be blocked by the RO membrane.
- The last is a ultra-violet lamp that eliminates any organisms that have been left by the filtration process.
How The Filtration System Works?
- The contaminated water is passed through the membrane, which blocks the contaminants.
- To push the water through the membrane the water system provides a pressure approximately of 40 psi.
- High quality reverse osmosis filtration system uses a process known as ‘cross flow’ by which the membrane can clean itself.
- The contaminants are swept away down an outlet.
- Reverse osmosis water filtration is eco friendly. During the process, there is no production of harmful chemicals.
- It consumes less power.
- They are small in size.
- The purified water has a pleasant taste as reverse osmosis removes the minerals.
- It does not corrode.
- The treatments require enormous amounts of water for a return of only 5 to 10 %.
- It also takes a long time to treat the water.
- It is also quite expensive to use in homes.