Principle of Reverse Osmosis Desalination Technology

Natural water contains a large number of dissolved impurities, which cannot be removed by conventional filtration methods.

Reverse osmosis desalination technology adopts reverse osmosis membranes with selective permeability. By applying a pressure higher than the osmotic pressure of the solution on the raw water side of the membrane, only water molecules are allowed to pass through the reverse osmosis membrane, while other substances are intercepted and separated.

Advantages

The key reverse osmosis membrane elements of our reverse osmosis water treatment equipment adopt world-famous brands such as Dupont and GE. The equipment features the following advantages:

1. The equipment is capable of long-term continuous operation with a high and stable water desalination rate, requiring no periodic regeneration.

2. The entire treatment process only consumes power for the high-pressure pump, without consuming chemical materials such as acid and alkali. It features low operating cost and zero discharge of chemical pollutants.

3. The equipment is simple to operate, can be started and stopped at any time, and is easy to realize automatic control together with pure water tanks and other supporting equipment.

4. The equipment is compact in size and low in height, suitable for installation in ordinary-height factory buildings.

Raw Water Requirements

Water Quality: It is generally applicable to municipal water supply that complies with GB5749 standard. The main indicators are as follows:

turbidity ≤ 1 NTU,

iron ≤ 0.3 mg/L,

residual chlorine ≤ 0.3 mg/L.

For areas with unstable water supply quality and non-municipal water sources, corresponding enhanced pretreatment measures shall be adopted according to actual conditions.

Temperature: 10~45℃.

Pressure: Under full-load operation of the equipment, the stable inlet water pressure shall be 0.2~0.3 MPa.

Functions of Pretreatment Equipment

Raw water must go through pretreatment before entering the reverse osmosis treatment equipment. The pretreatment process and requirements are related to factors such as the type of raw water and local environmental conditions. The commonly equipped pretreatment devices for pure water equipment and their functions are as follows:

Sand Filtration

Remove suspended solids, particles and other impurities in water. Coagulant dosing is required when necessary.

Activated Carbon Adsorption

Remove colloids and residual chlorine in water.

Precision Filtration

Further deeply remove suspended solids in water.

Iron Removal

Prevent iron from depositing on the membrane surface and causing irreversible membrane fouling and blockage.

Softening or Scale Inhibitor Dosing

Prevent the deposition of insoluble salts such as calcium and magnesium.

Ultrafiltration

Remove suspended solids, colloids and other impurities in water, and even partial microorganisms and pyrogens.

Treatment Process and Effluent Water Quality：