Which substance is commonly used to control the pH of boiler water?

Caustic soda, also known as sodium hydroxide, is commonly used to control the pH of boiler water because it effectively raises the pH levels, helping to prevent corrosion of the boiler's metal components. Maintaining an appropriate pH level is crucial for the operation of boilers; a too low pH can lead to acidic conditions that accelerate corrosion, while a too high pH can cause scale formation and reduce the efficiency of heat transfer.

In boiler water treatment, using caustic soda allows for adjusting the alkalinity and ensuring that the water chemistry remains balanced, which is essential for the longevity and efficiency of the boiler system. This makes caustic soda not only an effective pH control agent but also a necessary substance in ensuring safe and optimal boiler operation.