Removal of dissolved oxygen from boiler feed water for corrosion prevention in power stations
Boiler/turbine operation in power stations typically involves mechanical deaeration of the boiler feed water to reduce the dissolved oxygen content to less than 1 ppm. However, even traces of dissolved oxygen can cause severe pitting problems in the boiler tanks. Complete removal is achieved by the addition of an oxygen scavenger. However, the scavengers used are unstable at high temperatures and, depending on the type of scavenger used result in scale formation or the production of Class 2 carcinogens. PCR allows the scavenger to be contained downstream of the membrane so that water can be deoxygenated without coming into direct contact with the scavenger. This process allows the dissolved oxygen concentration to be reduced to parts per billion levels.