Reverse osmosis system consists of a reverse osmosis membrane, a high pressure pump and a security filter for protecting the reverse osmosis membrane.
The basic working principle of reverse osmosis is: using a special high-pressure water pump, the raw water is added to a pressure of 6-20 kg, so that the raw water permeates through the reverse osmosis membrane with a pore diameter of only 0.0001 μm under the action of pressure.
Chemical ions and bacteria, fungi, and virions cannot pass, and with the discharge of wastewater, only water molecules and solvents having a volume of less than 0.0001 μm are allowed to pass.
The filter has a filter element with a filter pore size of 5 μm. These filters filter out any particles larger than 5μm. It protects the downstream RO membrane, otherwise the surface of the RO membrane is extremely easy to scale. The more common type of permeable membrane is a polyamide membrane, and the membrane type is a wound composite membrane, and the membrane has a salt removal rate of 99.5%.
Since the RO membrane is susceptible to the pH value, residual chlorine and water temperature in the water, the RO membrane has strict requirements on the influent water quality before operation:
PH value: 3~10
Residual chlorine value: <0.1mg/L
SDI15 value: <5.0
Water temperature: <45 °C
If any of the above indicators are out of range, it is possible to deform the permeable membrane, thereby affecting the quality of the effluent and shortening the service life of the membrane. And the type of membrane is different for the influent water quality requirements. It can be confirmed according to the instructions provided by the RO membrane manufacturer before commissioning.
