Tennessee Wastewater Operator Practice Exam

What occurs when the blower speed is slowed down?

1. A curved line above the full speed curve is created

2. A new operating curve that is parallel and below the full speed curve is created

3. The blower becomes less efficient

4. The pressure increases significantly

The correct answer is: A new operating curve that is parallel and below the full speed curve is created

When the blower speed is slowed down, a new operating curve that is parallel and below the full speed curve is created. This phenomenon occurs due to the relationship between the blower speed and the volume of air it moves. As the speed decreases, the flow rate reduces, leading to a drop in the overall performance of the blower, but still maintaining the same efficiency characteristics. In this context, the new operating curve remains parallel to the original curve under full speed because, while the absolute flow rate is reduced, the system’s characteristics related to resistance and airflow dynamics essentially change in a uniform manner, reflecting lower airflow at reduced speeds. This concept is fundamental in understanding how blowers and similar components perform within wastewater treatment systems. The monitoring and adjustment of blower speeds are crucial for maintaining optimal operational efficiency and balancing oxygen levels in aeration processes.