Tennessee Wastewater Operator Practice Exam

Increasing the concentration of solids in an aerobic digester improves what aspect?

1. Gas production

2. pH stability

3. Decomposition rates

4. Operational efficiency

The correct answer is: Decomposition rates

Increasing the concentration of solids in an aerobic digester primarily enhances the decomposition rates. This occurs because a higher concentration of organic material provides more substrate for the microorganisms responsible for breakdown processes. As these microorganisms metabolize the solids, they convert them into simpler compounds and gases, effectively accelerating decomposition. Additionally, with an increased concentration of solids, the microbial population can become more optimized, leading to improved metabolic activity. This direct relationship between the concentration of solids and the rate at which microorganisms decompose organic material is vital for maximizing treatment efficiency in the digester.