Time:2019.08.14
Operating conditions and modes of operation are closely related to membrane fouling rates. Operating conditions that directly affect membrane fouling include membranes
Flux, operating pressure, membrane flow rate and operating temperature.
(1) Membrane flux or operation pressure
MBR has two modes of operation: one is constant membrane flux, and the other is constant operating pressure.
When a constant membrane flux mode of operation is employed, the membrane flux is the key point to the long-term stable operation of the MBR system. There is a critical membrane flux, when the actual membrane flux is higher than the critical value, membrane fouling is increased.
When operating with a constant operating pressure, there is a critical operating pressure. If the operating pressure is above the critical, would cause rapid membrane fouling.
The critical operating pressure decreases as the pore size of the membrane increases.
(2) Membrane flow rate
Increasing the degree of water flow on the surface of the membrane can effectively reduce the deposition of particulate matter on the membrane surface and slow down membrane fouling.
But the water flow velocity is not as large as possible. When the velocity reaches a critical value, its further increase will not good for the ability. Moreover, the excessive flow velocity may also cause the sludge particles to be broken by breaking the activated sludge flocs, increasing the SMP to aggravate membrane fouling.
(3) Temperature
Temperature also has an effect on the filtration separation process of the membrane. Temperature per liter a 1°C increase can cause a 2% increase in membrane flux.
(4) Mode of operation
For the integrated MBR, the operation mode of the suction pump can effectively slow down the development of membrane fouling.