Which substance is not typically added to furnace flue gases for acid dew point reduction ?
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Answer: D. None of these
Explanation
All listed substances act as alkaline neutralizing agents to combat sulfur trioxide in flue gases. Ammonia reacts with sulfur trioxide to form ammonium sulfate powder, preventing liquid acid condensation. Fine dolomite and other alkaline powders neutralize acid vapors and raise the overall dew point threshold. Acid dew point corrosion occurs when sulfur trioxide in flue gases condenses on cooler metal surfaces. Injecting neutralizing additives into the exhaust gas stream effectively reduces sulfuric acid vapor concentrations. Selecting the appropriate additive depends on operating temperatures, fuel sulfur content, and ash disposal.
Power plants burning high sulfur fuels inject chemical additives to protect air heaters from severe corrosion. Controlling acid dew point problems extends equipment lifespan and reduces unexpected maintenance downtime. Using alkaline powders helps meet environmental emission standards while preventing catastrophic heat exchanger failures. Ammonia is a proven additive that reacts with sulfur trioxide to neutralize acidic flue gas components. Fine dolomite is commonly injected to react with sulfur oxides and prevent low temperature corrosion. Alkaline powders are widely used neutralizing agents, meaning none of the listed items are incorrect.
- Subject
- Engineering
- Category
- Chemical Engineering
- Topic
- —
- Difficulty
- medium
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