Membrane Seperation Process

Reverse osmosis (RO) is a filtration method that removes many types of large molecules and ions from solutions by applying pressure to the solution when it is on one side of a selective membrane. The result is that the solute is retained on the pressurized side of the membrane and the pure solvent is allowed to pass to the other side. To be "selective," this membrane should not allow large molecules or ions through the pores (holes), but should allow smaller components of the solution (such as the solvent) to pass freely.
In the normal osmosis process the solvent naturally moves from an area of low solute concentration, through a membrane, to an area of high solute concentration. The movement of a pure solvent to equalize solute concentrations on each side of a membrane generates a pressure and this is the "osmotic pressure." Applying an external pressure to reverse the natural flow of pure solvent, thus, is reverse osmosis. The process is similar to membrane filtration. However, there are key differences between reverse osmosis and filtration. The predominant removal mechanism in membrane filtration is straining, or size exclusion, so the process can theoretically achieve perfect exclusion of particles regardless of operational parameters such as influent pressure and concentration. Reverse osmosis, however, involves a diffusive mechanism so that separation efficiency is dependent on solute concentration, pressure, and water flux rate. Reverse osmosis is most commonly known for its use in drinking water purification from seawater, removing the salt and other substances from the water molecules.


Advantages of RO
Operating cost less than DM plant for TDS higher than 600ppm.
Ease of operation
Variation in TDS does not significantly alter performance of RO
Better purification
In addition to dissolved salts, RO removes colloids, organics and bacteria
Varied applications
       RO can be used to recycle and reuse treated waste water.
Superior Performance
Variation in TDS does not significantly after performance of Reverse Osmosis
Better Purification
Modular in Construction
Expand Capacity at Minimunm Cost
In addition to dissolved salts, RO Remove Colloids, Organics and Bacteria
RO can be used to recycle and reuse treated waste water
Reduction in Total Dissolved Solids (TDS)
Recovery of water for reuse from
   Cooling Tower blowdown
   Boiler blowdown
   Treated Effluents (Industrial/Sewage)
Retrofitting for performance enhancement of existing DM plant
Recycle of treated waste water

Special Features

- Product flow rate 1.2 - 60 m3/h.

- Salt rejection ranges from 90 - 98% depending upon feed water composition.

- Product recovery ranges from 50 - 80% based on feed water composition.
- Electrical 415 V, 3 ph, 50 Hz.

- Concentrate discharge directed to drain at 'O' psi.

- Possible to hook up sophisticated instruments and controls


- Modular design - capacity can be increased to suit  requirements.

- Fully assembled skid, tested prior to shipment, ease of installation and beneficial use.

- Non-corrosive low pressure piping – virtually maintenance free.

- Low on energy consumption.

- User friendly unit - does not require continuous monitoring.


- Ultra pure water for electronic industries

- Ultrapure water for pharmaceutical industries

- Process water for manufacturing plants

- Boiler feed water

- Beverage and food processing industry

- Drinking water

- Waste water
- Bio-technology

- Mineral water


- Poly propylene cartridge housing pre-filter.

- FRP pressure vessels.

- Spiral wound membrane elements of polyamide type.

- 16 stainless steel multistage pump.

- TEFC pump motor.

- 316 stainless steel high pressure piping

- Low feed pressure switch for pump protection.

- High feed pressure switch for membrane & pump protection.

- Motor starter with disconnect switch.

- Motor contactor with thermal overload protection.
- Sample valves for feed, product and concentrate.

- Concentrate check valve.

- Product check valve.

- Automatic feed shut-off valve.

- Cleaning connections.

- Full control panel instrumentation.

- Pump discharge pressure indicator.

- Feed and concentrate pressure indicator.

- Product and concentrate flow meters.

- Conductivity meter.

- Power on light.

- Fault alarm.

- Post shutdown system flush.

Ultra filtration is a method of removing very small particles from liquid. A membrane used with this method usually has pores that are 0.01 to 0.001 microns in size. This is small enough to remove most bacteria, viruses, high molecular weight substances, and polymer-type molecules. During ultra filtration the flow of liquid gets split into two streams, which is known as cross-flow separation. One stream goes through the porous membrane and is then called permeate, and the other is concentrated in the particles and other matter that have been unable to penetrate the membrane.

The process is commonly used for treating drinking water in compliance with strict standards. Many organisms have become resistant to other methods of disinfecting water, but an ultra filtration system removes pathogens by moving water through a membrane, physically removing each organism. The membranes themselves are often formed into small, hollow fibers that are less than a millimeter (about 0.04 inches) in diameter, which are bundled by the thousands in a filter housing. Modules that contain the membranes come in a variety of configurations, including spiral-wound, plate-and-frame, and tubular. The type and concentration of material that needs to be removed helps determine what kind of configuration is used.

Ultra filteration is low pressure crossflow membrane process for separating selective molecular weight species from a feed system.
The separation is based on selective MWCO (Molecular weight cut-off)
Water, Salts and Low molecular weight species selectively pass through the membrane for discharge, reuse or further treatment.
Ultrafilteration selectively removes
Suspended Solids
Oil and Grease
Metal Hydroxides

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