Tennessee Wastewater Operator Practice Exam

Mixer aerators improve process efficiency by providing what additional benefit?

1. Increased water temperature

2. Extra mixing energy along the tank floor

3. Reduction of odor

4. Adequate chemical dosing

The correct answer is: Extra mixing energy along the tank floor

Mixer aerators play a crucial role in wastewater treatment processes by enhancing both aeration and mixing within the tank. The significant benefit of providing extra mixing energy along the tank floor is critical for maintaining uniformity in the treatment process. This additional mixing helps to evenly distribute the microorganisms and chemicals throughout the wastewater, ensuring that all particles are adequately treated. The enhanced mixing effect also promotes better contact between the wastewater and the air being introduced, which facilitates improved oxygen transfer rates. This is essential for the aerobic treatment processes where microorganisms break down organic matter in the presence of oxygen. The uniform distribution of energy along the bottom of the tank allows for a reduction in dead spaces where stagnant water could occur, further improving the efficiency of the overall treatment process. In summary, the primary advantage of mixer aerators lies in their ability to provide extra mixing energy along the tank floor, optimizing both aeration and mixing for effective wastewater treatment.