Economic and Feasibility Analysis of Process Selection and Resource Allocation in Decentralized Wastewater Treatment for Developing Regions

摘要

Highly developed urbanized areas rely on centralized wastewater treatment and an elaboratelyplanned sewerage system. For developing regions and remote areas installing a centralized plantand achieving maximum coverage with a sewerage system connecting to that plant implies highcapital cost. In such cases, it is feasible for these regions to opt for a multiple decentralizedtreatment plants. Septic tanks and wetlands are the current scenario of onsite and decentralizedsystems. These options have a large area requirement (Brissaud, 2007). More “sophisticated”options like the activated sludge process have large energy consumption. This paper overviewsvarious existing decentralized treatment systems all over the world to form deductions on thefootprint and energy consumption of these systems. It also theoretically compares the footprintand energy requirement for conventional biological unit processes based on their design for threeflow rates. Overall, this study suggests a methodology for the initial process selection during theplanning of a decentralized wastewater system.