what is ro plant and what is the role of mebrane in tha ro plant explain the whole system with flow chart.?

Answer 1

Reverse osmosis is the process of pushing a solution through a filter that traps the solute on one side and allows the pure solvent to be obtained from the other side. More formally, it is the process of forcing a solvent from a region of high solute concentration through a membrane to a region of low solute concentration by applying a pressure in excess of the osmotic pressure. This is the reverse of the normal osmosis process, which is the natural movement of solvent from an area of low solute concentration, through a membrane, to an area of high solute concentration when no external pressure is applied. The membrane here is semipermeable, meaning it allows the passage of solvent but not of solute.

The membranes used for reverse osmosis have a dense polymer barrier layer in which separation takes place. In most cases the membrane is designed to allow only water to pass through this dense layer while preventing the passage of the solute (e.g. salt). This process requires that a high pressure be exerted on the high concentration side of the membrane, usually 2 - 14 bar (30 - 200 pounds per square inch) for fresh and brackish water, and 40 - 70 bar [(600 - 1000 psig)] for seawater, which has around 24 bar (350 psi) natural osmotic pressure which must be overcome.

This process is best known for its use in desalination (removing the salt from sea water to get fresh water) and has been used in this way since the early 1970s. Its first practical demonstration was done by Sidney Loeb and Srinivasa Sourirajan from UCLA in the California town of Coalinga.

http://science.howstuffworks.com/question29.htm

For schematic diagram,pl. click:
http://www.zenon.com/image/resources/glossary/reverse_osmosis/reverse_osmosis.jpg
http://www2.hawaii.edu/~nabil/H2osch2.gif

Answer 2

no flow charts in a text box

RO (reverse osmosis) is the process of creating pure water from impure.

it was discovered that if a very thin water tight film was used to seperate impure and pure water then the pure water would transfer across the barrier to become impure, this process is called osmosis.

it was discovered that the osmosis process could be reversed by pressurisng the impure water above the pressure of the pure water, thus creating fresh water from impure.

the membrane is the barrier that allows the osmosis process to occur, seperating the impure and pure water.