Question 422Steam Plants - Assistant Engineer

The correct answer is A) treating the water with chemical scavengers. Dissolved oxygen in boiler water can lead to corrosion and pitting of the boiler metal. To remove dissolved oxygen, chemical scavengers such as hydrazine or sodium sulfite are added to the boiler water. These chemicals react with and remove the dissolved oxygen, preventing the corrosive effects. The other options are incorrect because: B) dumping and refilling the boiler weekly would not effectively remove dissolved oxygen, C) passing the water through absorbent filters would not chemically react with and remove the dissolved oxygen, and D) frequent surface and bottom blows would primarily remove sediment and impurities, not dissolved oxygen.