Reverse Osmosis is a technique for the removal of the total dissolved solids in water. The separation process is derived from the naturally occurring phenomenon known as Osmosis.
The Reverse Osmosis process comprises of two waters separated by a semi-permeable membrane one of a high concentration of dissolved solids and one with a low concentration. The semi-permeable membrane will only allow pure water to pass through leaving the solids behind. If a pressure is applied to the water containing the high concentration of solids then the volume of water on the low concentration side of the membrane is increase hence pure water, known as ‘permeate’ is produced.
As this process proceeds the concentration of solids in the water on the high-pressure side is increased and if this were allowed to continue fouling would eventually occur. To prevent this a proportion of the water on the high concentration side is continually discharged to drain allowing fresh water to enter the system and dilute the solids level. The discharge water is known as the ‘reject’ water.
PWEL reverse osmosis units are supplied mounted on a steel reinforced polypropylene square section base frame with plastic front plate on which is fitted the control panel.
The reverse osmosis system comprises of the following;-
- Inlet filter housing with 5 micron cartridge elements, pre and post filter pressure gauges.
- A Grundfos low-noise, multi-stage centrifugal type inverter driven high-pressure pump.
- Low energy TFC modules with energy saving PA/PS membranes.
- GRP membrane pressure vessels with line
- Inlet control valve.
- Inlet water pressure-switch to protect the pump in the event of low pressure or no flow.
- Permeate, Concentrate and Reject flow meters.
- Pressure gauges for inlet and concentrate water pressure.