What is Reverse Osmosis?
Reverse Osmosis commonly knowns as RO, is a technology to remove dissolved solids and impurities from water by a semi-permeable membrane which allows the water passing through but reject the majority of other contaminants. The RO membranes require water to be under high pressure (greater than osmotic pressure) to achieve the goal. The water that passes through the RO membrane is called "permeate" and the dissolved salts that are rejected by the RO membrane is called "concentrate".
To understand the purpose and process of Reverse Osmosis you must first understand the naturally occurring process of Osmosis.
Osmosis
Osmosis is the movement of a solvent across a semipermeable membrane toward a higher concentration of solute from the lower side. Osmosis is a naturally occurring phenomenon and one of the most important processes in nature. It is a process where a weaker saline solution will tend to migrate to a strong saline solution. Examples of osmosis are when plant roots absorb water from the soil.
Reverse Osmosis
Reverse Osmosis is the process of Osmosis in reverse. Whereas Osmosis occurs naturally without energy required, to reverse the process of osmosis you need to apply energy to “push”. A reverse osmosis membrane is a semi-permeable membrane that allows the water molecules passing through but reject the majority of dissolved salts, organics, bacteria and pyrogens. However, you need to ‘push‘ water through the RO membrane by applying pressure(greater than the osmotic pressure) in order to desalinate (demineralize or deionize) water in the process, allowing pure water through while rejecting a majority of contaminants.
Single Pass RO Pure Water System
According to the times of raw water passing through the RO membrane, RO device can be devided into the single or double or even multilevel pass RO. Different times of passing through membrane will result different quality permeate water.
A complete RO system includes pretreatment & RO unit. The flow chart of a standard single pass RO is as following:
Main Components
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CNP Water Pump | Grundfos Water pump | DOW RO Membrane |
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Ionpure EDI Module (Siemens) | Stainless Steel Pipe Parts | SEKISUI Clean-PVC |
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Schneider Electronic Parts | Siemens PLC Controller | Electrical Control Cabinet |
Successful Cases
http://www.rxd-purewatersystem.com/