How much TSS is typically removed during primary treatment?

During primary treatment of wastewater, typically 50-70% of total suspended solids (TSS) is removed. This level of removal is achieved through processes such as sedimentation, where heavier solids settle to the bottom of a treatment tank, and flotation methods that separate solids from the liquid. The primary treatment focuses on the physical separation of solids from the liquid phase, which results in a significant reduction in TSS.

This range of removal is effective for targeting larger particles and organic matter, thus reducing the load on subsequent treatment processes. It is essential to understand that while primary treatment addresses a substantial portion of TSS, higher percentages of removal, such as those indicated in other options, are typically achieved in secondary treatment stages that employ biological processes.