Engineering · Steam — Water Treatment
Dissolved oxygen in boiler feedwater is harmful chiefly because it causes:
- AFoaming
- BPitting corrosion of boiler metal✓ Correct
- CScale formation
- DCarryover of water into the steam
Explanation
Dissolved oxygen attacks steel and causes localized pitting. It is removed by the deaerator and chemically scavenged (e.g., with sodium sulfite or hydrazine).
Authority: Steam Plants (USCG engineering topic)
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