Which process is primarily responsible for the removal of soluble organic matter?

The removal of soluble organic matter is primarily achieved through secondary treatment. This stage follows primary treatment, where physical processes are used to remove larger solids. Secondary treatment typically involves biological processes, such as activated sludge systems or trickling filters, where microorganisms break down organic matter into simpler compounds.

In this stage, the microorganisms consume the organic materials dissolved in the wastewater, effectively reducing the biochemical oxygen demand (BOD) and total suspended solids. The outcome is a significant decrease in the concentration of soluble organic materials, transforming the wastewater into a more manageable state before it undergoes further treatment or is discharged into the environment. This biological degradation process is essential for ensuring that the remaining wastewater is more environmentally friendly and meets required discharge standards.