Plant Operation Practice Test

What is added to the boiler water to change scale-forming salts into non-adhering sludge?

1. Corrosion inhibitors

2. Detergents

3. Slag

4. pH stabilizers

The correct answer is: Slag

The addition of certain substances to boiler water is essential for maintaining optimal operating conditions. In this case, the correct approach for managing scale-forming salts involves treating them to prevent scale buildup on boiler components. Slag, which is formed from the reaction of certain additives with scale-forming salts, helps convert these materials into non-adhering sludge. This transformation is critical because adhering scale can lead to heat transfer inefficiencies, increased fuel consumption, and potential damage to the boiler system over time. By creating sludge that can be easily removed, the efficiency of the boiler is maintained, and the risk of operational issues is minimized. While the other options mentioned may have their roles in boiler water treatment, they do not perform the specific function of treating scale-forming salts into a manageable form like non-adhering sludge. Corrosion inhibitors focus on preventing corrosion within the boiler, detergent functions primarily in cleaning processes, and pH stabilizers are used to maintain a balanced pH in the water, but none of these specifically convert scale-forming salts into sludge.