AN EXPERIMENTAL INVESTIGATION ON SEWAGE TREATMENT PLANT

Abstract

Sewage water treatment aimed at optimizing purification methods and ensuring environmentally compliant discharge. With increasing urbanization and pressure on water resources, efficient treatment technologies are essential to mitigate pollution, protect public health, and promote sustainable development. The objective is to assess the performance of conventional and advanced treatment methods and identify the most effective combination for municipal wastewater purification. Raw sewage samples were collected from a local treatment facility and analyzed for pollutants, including Biological Oxygen Demand (BOD), Chemical Oxygen Demand (COD), Total Suspended Solids (TSS), pH, turbidity, and microbial content. The experimental setup followed a three-tier treatment process: primary (physical sedimentation), secondary (biological treatment via activated sludge), and tertiary (disinfection using chlorination and ultraviolet irradiation). Each stage was controlled for variables such as retention time, aeration rate, and chemical dosage. The primary treatment removed coarse solids and reduced turbidity by approximately 45%. In the secondary stage, aerobic microorganisms facilitated biodegradation, reducing BOD and COD levels by up to 80–85%. Tertiary treatment, applied to refine effluent quality, achieved over 95% pathogen elimination, validating its effectiveness for safe reuse or discharge. A comparative analysis revealed the UV disinfection system to be more consistent and less chemically intensive than chlorination. Further observations examined the role of aeration dynamics, sludge age, and temperature in biological treatment efficacy. The study also explored economic viability, suggesting that hybrid systems with solar-powered UV units could be ideal for decentralized rural applications. Recommendations include regular monitoring, design optimization based on influent characteristics, and integration with circular water economy models.