Basic Wastewater Operator Practice Exam

What is the primary purpose of chlorination in a wastewater treatment process?

1. To promote anaerobic digestion

2. To increase dissolved oxygen levels

3. To disinfect the water

4. To enhance sedimentation

The correct answer is: To disinfect the water

Chlorination is primarily employed in wastewater treatment to disinfect the water. This process involves adding chlorine or chlorine compounds which effectively kill harmful pathogens and bacteria present in the wastewater. The goal is to reduce or eliminate microorganisms that could pose a health risk to humans and the environment upon discharge into water bodies or when the treated water is reused. Disinfection is a critical step in ensuring the safety of treated effluent, which may be released back into the ecosystem or used for irrigation and other purposes. While chlorination does not directly contribute to promoting anaerobic digestion, increasing dissolved oxygen levels, or enhancing sedimentation, it plays a vital role in preventing the spread of waterborne diseases and maintaining public health standards.