Most of the people now a days are switching to reverse osmosis water purifying systems for consuming safe and pure water. The reverse osmosis process is the most unique and advanced purifying technology that is used by various water treatment plants in order to purify water. There are several companies who have launched their purifying systems for commercial use, which utilizes reverse osmosis process.

The reverse osmosis process is the reverse of osmosis process. In osmosis process the solution is filled up in a tank and pressure is applied from the side where the concentration of particles is less. It can also be defined as the process in which there is a spontaneous flow of water from the diluted side to the much-concentrated side when the both sides are separated by a thin membrane. The reverse osmosis process has a lot of similarity with the membrane filtration treatment process. During the removal process in membrane filtration, there is a straining which results in size exclusion. Therefore regardless of the efficient operational parameters, the tiny microorganisms are excluded from the whole filtration process. Whereas in reverse osmosis, there is a very thin membrane that does not allows tiny microorganisms like bacteria and virus to pass through it.

complete reverse osmosis filtration process has various filters. With due course of time and purifying large volumes of water, the thin membrane and other filters become less efficient and then there generates a need to replace these filters. The water purifier companies have the replacement filters and can replace the ineffective filter upon request.

new replaced filters can have a six-stage purification level and might consist of the following filters:

• A sediment filter to restrict all waste particles like calcium carbonate and rust

• A second sediment filter to restrict smaller particles and has relatively much smaller pores

• A carbon filter to restrict all organic chemicals like chlorine and others, which might reduce the efficiency of the tiny film composite reverse osmosis membrane.

• Another second carbon filter to trap the remaining chemicals those are not removed by the previous reverse osmosis membrane

• Further a ultra-violet lamp is also installed for disinfecting various tiny microorganisms that might escape the reverse osmosis membrane filtration.

e replacement filters might also have a cellulose triacetate membrane instead of the carbon pre-filter. The cellulose triacetate membrane is prone to rotting if it is not protected from chlorinated water, while the thin film cellulose membrane is prone to breakage if they are not prevented from chlorinated water. Therefore a post carbon filter is used to remove the chlorinated water from the final purified water.