Texas Wastewater Class B Practice Exam

What does a plugged air diffuser in an aeration tank cause?

1. Decreased air flow and mixing

2. Improved nutrient removal

3. Increased effluent clarity

4. Stable dissolved oxygen levels

The correct answer is: Decreased air flow and mixing

A plugged air diffuser in an aeration tank primarily leads to decreased airflow and mixing. The role of the air diffuser is to introduce air into the tank, which promotes the growth of aerobic microorganisms that help in the breakdown of organic matter. When the diffuser becomes clogged, it cannot efficiently allow air to pass through, resulting in reduced oxygen levels in the tank. This decrease in airflow directly affects the mixing of the contents within the tank. Effective mixing is crucial in maintaining uniform conditions for biological processes and ensuring that the microorganisms have adequate access to both nutrients and oxygen. Thus, the consequences of a clogged diffuser highlight the importance of regular maintenance and monitoring to ensure optimal performance of the aeration system.