ANALYSIS OF CLEARIFIER SLUDGE GENERATION AND COMPRESSIBILITY AS A BASIS FOR SLUDGE REMOVAL OPTIMIZATION

Abstract

Clarifiers in Water Treatment Plants (WTPs) generate sludge through the accumulation of suspended particles and chemical coagulants, making sludge estimation essential for efficient plant operation. This study investigates the relationships between clarifier influent characteristics, sludge generation, and sludge compressibility to optimize sludge discharge operations. A quantitative experimental approach was employed by measuring turbidity, Total Suspended Solids (TSS), and sludge volume through Imhoff cone sedimentation tests conducted at intervals of 10–120 minutes. Twenty samples were purposively collected
from the clarifier inlet over two weeks. Linear regression analysis revealed a strong relationship between turbidity and TSS (R² = 0.9936), expressed as TSS (mg/L) = 1.2634 × Turbidity (NTU) + 2.3212. TSS also strongly correlated with sludge volume (R² = 0.9269), following the equation Sludge Volume (mL/L) = 0.06 × TSS (mg/L) − 0.782. Sedimentation observations indicated a transition from flocculent settling to compression settling at higher TSS concentrations, resulting in reduced sludge volume due to interparticle pressure. These findings supported the development of a dynamic mathematical model of sludge accumulation and compressibility, integrated into a Microsoft Excel-based monitoring dashboard. The proposed approach provides a practical tool for estimating sludge generation, supporting sludge discharge scheduling, and improving operational control of WTP clarifiers.