Basic Wastewater Operator Practice Exam

Which process utilizes microorganisms to break down organic matter in activated sludge systems?

1. Oxidation

2. Filtration

3. Photosynthesis

4. Hydrolysis

The correct answer is: Oxidation

The process that utilizes microorganisms to break down organic matter in activated sludge systems is oxidation. In this context, oxidation refers to the biochemical processes carried out by microorganisms, such as bacteria, that convert organic compounds into simpler substances. This is a critical part of the wastewater treatment process, as it effectively reduces the concentration of organic pollutants and helps to stabilize the waste. Microorganisms in activated sludge systems thrive in an aerobic environment, where they consume organic matter for energy, thus oxidizing it into carbon dioxide, water, and biomass. This not only helps to reduce the organic load on the wastewater but also promotes the growth of useful microbial populations that aid in further treatment processes. In contrast, filtration primarily involves separating solids from liquids without necessarily breaking them down. Photosynthesis refers to the process by which plants and some microorganisms convert light energy into chemical energy, utilizing carbon dioxide and water, which is not relevant in the context of organic matter breakdown in wastewater. Hydrolysis is a different step in the degradation process where complex organic materials are broken down into simpler compounds, often preceding oxidation, but it does not directly involve the same microbial activity associated with oxidation in activated sludge systems. Overall, oxidation is fundamental in achieving the desired treatment outcomes within activated sludge processes, making it the