Reverse osmosis by the turn of last four decades, however, became the most efficient and sophisticated manufacturing, processing, and purifying system for getting pure drinking water. Osmosis is a natural process and it occurs when two liquids of different concentration of solutes are separated by a semipermeable membrane, the liquid or solvent that passes from the low concentration zone to high solute concentration zone to make equilibrium. The name reverse osmosis itself speaks that the process here is just reverse. That means in RO system a solvent or a liquid is forced to pass from a high solute concentration zone to a low solute concentration zone through a semipermeable membrane. Naturally, a force more than osmotic pressure is required to execute reverse action. This is done to get pure water and commercial process of RO system is used by companies, hospitals, large restaurants and hotels, labs etc.
What makes up a complete RO system?
A complete reverse osmosis procedure, however, includes different components, such as:
- Pre-treatment — It requires carbon filters to eliminate carbon, filters for removing iron, manganese, and sulfur, water softeners, or anti-scalant systems.
- Storage and distribution — Ro system works slowly and therefore, a storage tank is required to store water. Generally, two types of tanks are available. One is atmospheric, it is bigger in size and another one is bladder type, a smaller one. Bladder tanks are used to store 14 to 80 gallons water and for a larger volume from 75 to 2000 gallons water, an atmospheric tank is used. While an atmospheric tank is used a booster pump will be required to re-pressure the water for distribution purpose.
- Post-treatment — Under this stage, UV disinfection is added to kill bacteria, pH is adjusted to raise the pH or deionize the water.
- Instrumentation — As the quality of water is the prime objective of RO system a number of instruments and analyzers are used to facilitate the system.
- Complete RO system components — These are:
- Backwashing carbon filter
- RO component
- Atmospheric tank
- Anti-scalant component
- UV disinfection
- .2 micron post filter
- Deionization cartridge
- Quality light
- Distribution and re-pressurization pump
Designing a commercial RO system
- The function of a commercial RO system reaches its highest level when it is attached to an open-air or atmospheric tank. If there is back-pressure from the bladder of the pressurized storage tank, the commercial RO system should deliver low TDS (Total Dissolved Solid) water. The TDs will however nearly be zero when RO is discharged to an atmospheric tank. In a manufacturing process where low TDS or zero TDS is a precondition, an atmospheric tank is by and large the solution.
- Proper pre-treatment is a precondition for the successful commercial RO system. In most cases, backwashing carbon filter and water softener are fed ahead of the system to protect the membrane from scaling.
- Several pumps and UV disinfection are used to prevent intrusion of air-borne or water-borne bacteria into the atmospheric tank.
- An atmospheric tank is required to store the pure RO water.