PERFORMANCE EVALUATION OF STPs BASED ON DIFFERENT TECHNOLOGIES IN DELHI/NCR

Abstract

India faces a number of water and wastewater issues and water related health hazards. These problems arise primarily due to the increasing level of qualitative and quantitative depletion of water resources owing to over-utilization and continuous discharge of wastewater. Sewage Treatment Plants (STPs) have been constructed in most places to reduce the degradation of water quality of the receiving water bodies by reducing the total pollution load on the same and to ensure a healthy environment both aesthetically along with preserving the ecosystem involved. However, the purpose of establishing the STPs is not met until their effectiveness in treating sewerage is ensured which has been observed as a major concern throughout the Country. In view of a varied experience with different technologies under the various river action plans that have been initiated from time to time, a need for a case study was perceived to assess technologically and financially suitable options for sewage treatment. Technologies which are being used in other parts of the world are being deployed in India on a large scale and it is well established that each technology has its own merits and demerits. Therefore, their techno-economic viability under Indian conditions needs to be proven and will depend on prevailing local conditions, urban settings, community acceptability, etc. The work carried out in this report presents the results of the evaluation carried out for the techno-economical and environmental performance with particular emphasis on six (6) STPs based on different treatment technologies such as Upflow Anaerobic Sludge Blanket (UASB), Sequential Batch Reactor (SBR), BIOFOR, Activated Sludge Process (ASP), Activated Sludge Process combined with BIOFOR (ASP + BIOFOR) and Oxidation ditch located in Delhi/NCR region for handling and treating the domestic wastewater generated from the designated localities under specific STPs. The parameters which were monitored under the study included pH, Total Suspended Solids (TSS), Biochemical Oxygen Demand (BOD), Chemical Oxygen Demand (COD), Mixed Liquor Suspended Solids (MLSS), Total Coliform (TC) and Fecal Coliform (FC). In addition to the evaluation of the performance of the STPs based on different treatment technologies, the same were also analyzed for the capital cost, operation and maintenance costs, energy requirements and land requirement, which is primarily based on the data as obtained from various STPs in the Ganga River Basin and information collected as well as compiled from various sewage treatment technology providers.