California Wastewater Treatment Operator Practice Exam 2025 – All-in-One Guide to Master Your Certification

Controlling pH levels during the wastewater treatment process is essential for maintaining optimal conditions for biological treatment and ensuring compliance with regulatory standards. Utilizing chemical additives or biological processes is the most effective method for achieving pH control.

Chemical additives such as acids (e.g., sulfuric acid) or bases (e.g., sodium hydroxide) can be introduced into the wastewater to directly adjust the pH to desired levels. This is particularly important when the wastewater has extreme pH values that could inhibit microbial activity or interfere with treatment processes.

Biological processes also play a significant role in regulating pH. Certain microorganisms can produce acids or alkalies as metabolic byproducts, influencing the pH of the surrounding environment. For instance, during anaerobic digestion, the breakdown of organic materials can lead to a production of volatile fatty acids, potentially lowering the pH. Conversely, other biological processes, like the growth of photosynthetic algae, can increase pH by consuming carbon dioxide during photosynthesis.

In contrast, aeration alone primarily focuses on oxygen transfer to support aerobic microorganisms and does not directly address pH levels. Adjusting temperature may affect the rate of biochemical reactions, but it is not a control method for pH itself. Reducing flow rates can alter the treatment