Florida Wastewater Practice Test

What is the ideal temperature range for an aerobic digester’s operation?

1. 20-30°C

2. 30-40°C

3. 40-50°C

4. 10-20°C

The correct answer is: 30-40°C

The ideal temperature range for an aerobic digester's operation is between 30-40°C. This temperature range is optimal for facilitating the growth of aerobic microorganisms, which play a critical role in the digestion process. At this temperature, the metabolic activities of these microorganisms are enhanced, leading to more efficient breakdown of organic matter, better conversion of waste into stable end products, and overall improved treatment efficacy. Operating an aerobic digester at this ideal range also helps in maintaining the balance of microbial populations within the system. When the temperature is too low, such as in the 10-20°C range, microbial activity slows down, leading to inefficient digestion and potential issues such as odor problems and increased retention time. Conversely, if the temperature rises beyond the 40-50°C range, it may create a stressful environment for the microorganisms, which can reduce their activity or even cause mortality in sensitive species. Therefore, 30-40°C is considered the most suitable range for maximizing the performance and stability of aerobic digesters.