Arkansas Boiler Operator Practice Exam

Why is blowdown performed in a boiler?

1. To add water to the system

2. To remove impurities and maintain efficiency

3. To cool the system down

4. To increase steam pressure

The correct answer is: To remove impurities and maintain efficiency

Blowdown is performed in a boiler primarily to remove impurities that accumulate in the boiler water over time. When water is heated to produce steam, various minerals and contaminants (like dissolved solids) can concentrate in the boiler due to evaporation. If these impurities are not removed, they can lead to scaling, corrosion, and reduced heat transfer efficiency. This accumulation can negatively impact the operational efficiency of the boiler and potentially lead to equipment failures. By conducting blowdown, water is drained from the boiler to reduce the concentration of these impurities, effectively maintaining the water quality within acceptable limits. This practice helps to ensure the boiler operates effectively, safely, and efficiently, extending its operational life and performance. Other choices, while related to boiler operations, do not accurately reflect the primary purpose of blowdown. For example, adding water to the system or cooling the system down address different maintenance needs, and increasing steam pressure does not directly relate to the blowdown process.