Carbonate Effects on Sodium Hydroxide Dosage

Hydrogen sulfide, H2S, causes major odor problems at wastewater treatment facilities. A primary method of removing hydrogen sulfide from air is to use a wet scrubber. In a wet scrubber the air stream comes in contact with a liquid scrubbing solution. In order for hydrogen sulfide to enter into solution, the pH of the scrubbing solution must be raised. Sodium hydroxide (NaOH) also known as caustic soda, is typically used in odor control systems to raise the pH of the scrubbing liquid. Neglecting carbonate effects leads to incorrectly low dosages for the amount of sodium hydroxide needed to raise the pH.