Question 69Steam Plants - 1st Asst/Chief

The correct answer is A) caustic embrittlement. Excessive alkalinity in boiler water, usually caused by excessive use of sodium hydroxide (caustic soda) for pH control, can lead to a condition known as caustic embrittlement. This occurs when the high pH causes the steel in the boiler to become brittle and susceptible to cracking or failure. The other options are incorrect because: B) is related to oxygen scavenging, not alkalinity; C) describes precipitation of scale due to hardness, not alkalinity; and D) is a general effect of scale formation, not specifically due to excessive alkalinity.