Arkansas Boiler Operator Practice Exam

What efficiency benefit does a feedwater heater provide before water enters the boiler?

1. It decreases the steam pressure required

2. It increases the temperature of the feedwater

3. It purifies the water completely

4. It filters excess steam

The correct answer is: It increases the temperature of the feedwater

A feedwater heater plays a crucial role in improving the efficiency of a boiler system by increasing the temperature of the feedwater before it enters the boiler. By utilizing waste heat from the flue gases or from the steam that would otherwise be vented, the feedwater heater elevates the temperature of the water entering the boiler. This process is significant because higher feedwater temperatures lead to improved thermal efficiency in the boiler operation. When the feedwater is pre-heated, it requires less energy to reach the boiling point. As a result, the boiler can operate more efficiently, producing steam with less fuel consumption. This not only conserves energy but can also lead to reduced operational costs. Additionally, it minimizes thermal shock to the boiler components and helps maintain overall system efficiency and longevity. The other options do not directly address the primary role of a feedwater heater. While decreasing steam pressure might be an operational consideration, it is not a direct benefit of a feedwater heater. Purifying water completely is not achievable solely through a feedwater heater, and filtering excess steam is not its function. Thus, the increase in temperature provided by the feedwater heater is the key factor in its efficiency benefit in boiler operations.