Increasing the amount of limestone in the scrubber slurry is expected to do what with sulfur dioxide emissions?

Increasing the amount of limestone in the scrubber slurry is expected to do what with sulfur dioxide emissions?

• A. The amount of sulfur dioxide released will increase.
• B. The amount of sulfur dioxide released will decrease.
• C. The amount of nitrogen oxides released will decrease.
• D. There will be no change in emissions of sulfur dioxide.

Answer: (B)

Wet scrubbers remove sulfur dioxide by reacting it with a limestone (calcium carbonate) slurry to form calcium sulfite or calcium sulfate (gypsum). Increasing the amount of limestone in the slurry provides more reactive material to capture SO2 as the exhaust gas passes through the scrubber. With more limestone available, more SO2 can be converted and retained in the slurry, so less sulfur dioxide exits to the atmosphere. The process primarily targets SO2, not nitrogen oxides, so changing limestone won’t directly affect NOx emissions.

Wet scrubbers remove sulfur dioxide by reacting it with a limestone (calcium carbonate) slurry to form calcium sulfite or calcium sulfate (gypsum). Increasing the amount of limestone in the slurry provides more reactive material to capture SO2 as the exhaust gas passes through the scrubber. With more limestone available, more SO2 can be converted and retained in the slurry, so less sulfur dioxide exits to the atmosphere. The process primarily targets SO2, not nitrogen oxides, so changing limestone won’t directly affect NOx emissions.