What is the primary function of oxygen scavengers in water treatment?

Oxygen scavengers are chemical agents used in water treatment systems, particularly in boiler applications, to remove free oxygen from water. Free oxygen in boiler feedwater can lead to corrosion of metal surfaces, which can significantly reduce the lifespan and efficiency of the boiler system. By effectively removing this free oxygen, oxygen scavengers help to prevent corrosion and thereby maintain the integrity of the boiler components.

When water is heated in a boiler, any remaining free oxygen could react with the metals in the system, producing oxides that weaken the metal structure. Oxygen scavengers work by chemically reacting with the dissolved oxygen, thus neutralizing its potential corrosive effects. Common oxygen scavengers include compounds like sodium sulfite and hydrazine, which bind with the oxygen and remove it from the system.

Removing free oxygen is crucial for maintaining a safe and efficient operation of the boiler and preventing costly repairs or replacements due to corrosion-related failures. This is why the function of oxygen scavengers is essential in water treatment processes within power engineering.