EFFICIENCY EVALUATION OF SEWAGE TREATMENT PLANTS IN DELHI

Abstract

Water is one of the integral natural resources that is essential for the existence of life in all forms on the Earth. Extension of Civil Engineering into the specialization of Environmental Engineering has taken place because of the presence of conventional topics like water supply/shortage, releasing of effluents, sewage which also requires an individual’s attention on a regular basis, leading to the introduction of how they can be treated. The dire need to conserve the presently available water resources has also led to the initiation of tertiary treatment of wastewater. Urban drainage system is considered as an important means to remove effluents, treat wastewater and polluted discharge, so as to prevent the city from unhygienic conditions that may take a serious toll on public health in the long run. One of the prime domains of urban drainage system is Sewage treatment plants (STP).

In this thesis, we first analyze the wastewater in major STPs present in Delhi. The verification of presence of these STPs is done by Delhi Jal Board (DJB) . We take the data of nearly 17 major treatment plants out of the 29 plants that we took under consideration. From the data acquired by Delhi Pollution Control Committee (DPCC), we calculate the efficiency of individual treatment plants on the basis of physical and chemical parameters, which will help us to determine the overall performance of the plant. Once we have the performance measures of the STPs, we compare the different technologies used in their working. Few of the technologies on which these STPs are based are Oxidation pond treatment process, Extended Aeration, Physical Chemical Biological removal treatment, Activated sludge process (ASP) etc. which eventually helps us to draw trends and make inferences related to the most underperforming and most suitable STPs.

Our study shows that the best results for STPs under consideration were majorly obtained from extended aeration process and activated sludge process (ASP) in fewer instances.