Membrane Contactors are used to deaerate water in a boiler. Membrane Contactors are getting increasingly popular. Membrane Contactors use a membrane which is made of hydrophobic material with pore size of the order of 0.03 micrometer.
On one side of the membrane, a gas, usually nitrogen, is passed at low pressure. On the other side, the water to be deaerated is passed. Since the membrane is hydrophobic, the water does not pass through it. But the gases which are dissolved pass through the membrane to the other side with low pressure.
The deaeration process can be controlled by varying the pressure of the gas and its concentration. The capacity of the contactor can be increased by adding more membranes. The membrane contactor method can produce water with a dissolved oxygen concentration of less than 1 ppb (parts per billion).
The advantages of using Membrane Contactors are:- Absence of Emulsions
- No Flooding even at high flow rates.
- No density difference between the fluids is required.
- High surface areas
