What characterizes the anaerobic process in wastewater treatment?

The anaerobic process in wastewater treatment is characterized by its operation in the absence of oxygen. This process relies on microorganisms that thrive in environments devoid of oxygen to break down organic matter, converting it into biogas, which primarily consists of methane and carbon dioxide. This method is particularly effective for the treatment of sludge and helps in stabilizing it, reducing odor, and producing renewable energy in the form of biogas.

Anaerobic treatment is advantageous for handling high-strength wastewater because the microbial processes are often more efficient in such conditions compared to aerobic processes. By not requiring oxygen, anaerobic treatment can also lead to lower operational costs, as it reduces the need for aeration and other oxygen supply methods.

In comparison, the other options do not accurately describe the anaerobic process. Utilizing sunlight reflects a photosynthetic process, which is not applicable to anaerobic conditions. Chemical treatment methods involve the addition of chemicals to facilitate reactions that typically do not engage biological processes in the same way as anaerobic digestion. Lastly, while anaerobic processes may assist in solid waste stabilization, their primary contribution is the breakdown of organic matter rather than solid waste removal per se.