What biological process is primarily used in wastewater treatment plants to reduce organic matter?

The biological process primarily used in wastewater treatment plants to reduce organic matter is aerobic digestion. This process involves microorganisms that thrive in the presence of oxygen to break down organic pollutants in wastewater. The microorganisms metabolize the organic matter into simpler compounds, which can then be more easily removed, resulting in cleaner effluent.

Aerobic digestion is favored in wastewater treatment because it is highly effective at reducing biochemical oxygen demand (BOD) – a measurement of the amount of organic material in water. The presence of oxygen ensures that these microorganisms can efficiently utilize the organic compounds as a food source, leading to a significant reduction in harmful substances.

In contrast, other methods listed, such as pyrolysis, involves thermal decomposition and is not used directly for treating wastewater. Filtration is a physical process that removes solids but does not target organic matter degradation. Electrodialysis is a method for desalination and separating ions but does not address the biological breakdown of organic compounds in wastewater.