Laboratory Demonstration and Preliminary Techno-Economic Analysis of an Onsite Wastewater Treatment System

TitleLaboratory Demonstration and Preliminary Techno-Economic Analysis of an Onsite Wastewater Treatment System
Publication TypeJournal Article
Year of Publication2020
AuthorsLena Trotochaud, Rebecca M. Andrus, Kayana J. Tyson, Graham H. Miller, Claire M. Welling, Patrick E. Donaghy, Joseph D. Incardona, William A. Evans, Paul K. Smith, Tim L. Oriard, Ian D. Norris, Brian R. Stoner, Jeremy S. Guest, and Brian T. Hawkins
JournalEnvironmental Science & Technology
Date Published12/2020
KeywordsBlackwater, electrochemical disinfection, granular activated carbon (GAC), ISO 30500, nonsewered sanitation system (NSSS), onsite wastewater treatment system (OWTS), techno-economic analysis, ultrafiltration

Providing safe and reliable sanitation services to the billions of people currently lacking them will require a multiplicity of approaches. Improving onsite wastewater treatment to standards enabling water reuse would reduce the need to transport waste and fresh water over long distances. Here, we describe a compact, automated system designed to treat the liquid fraction of blackwater for onsite water reuse that combines cross-flow ultrafiltration, activated carbon, and electrochemical oxidation. In laboratory testing, the system consistently produces effluent with 6 ≤ pH ≤ 9, total suspended solids (TSS) < 30 mg/L, and chemical oxygen demand (COD) < 150 mg/L. These effluent parameters were achieved across a wide range of values for influent TSS (61-820 mg/L) and COD (384-1505 mg/L), demonstrating a robust system for treating wastewater of varying strengths. A preliminary techno-economic analysis (TEA) was conducted to elucidate primary cost drivers and prioritize research and development pathways toward commercial feasibility. The ultrafiltration system is the primary cost driver, contributing >50% of both the energy and maintenance costs. Several scenario parameters showed an outsized impact on costs relative to technology parameters. Specific technological improvements for future prototype development are discussed.

Short TitleEnviron. Sci. Technol.