Ammonia dosing in condensate water

Ammonia dosing is a common method used to maintain pH in boiler water, and it is recommended for most HRSGs to maintain pH at 25 degree centigrade temperature within a range of 9.6—10.0.

Ammonia is a cheaper material used to maintain pH in boiler water, and it is known to scavenge dissolved oxygen and protect copper alloys from ammonia.

The purpose of ammonia dosing is to control the pH of water, which is kept slightly alkaline to avoid corrosion from chloride and other salts. A low ppb of dissolved oxygen can cause severe corrosion by pitting, so a slight residual of hydrazine is kept in the system.