Optimal design of an electrochemical reactor for blackwater treatment.

Journal Article (Journal Article)

Electrolysis of blackwater for disinfection and nutrient removal is a portable and scalable technology that can lessen the need for cities to construct large-scale wastewater treatment infrastructure and enable the safe onsite reuse of blackwater. Several systems for treating wastewater from single toilets are described in the literature, but there are few examples of systems designed to use electrolysis to treat blackwater from nearby toilets, which is a situation more common in densely packed urban living environments. In order to scale a single toilet electrolysis system to one that could service multiple toilets, computational fluid dynamic analysis was used to optimize the electrochemical reactor design, and laboratory and field-testing were used to confirm results. Design efforts included optimization of the reactor shape and mixing to improve treatment efficiency, as well as automated cleaning and salt injection to reduce maintenance and service requirements. PRACTITIONER POINTS: Design of a reverse polarity mechanism to enable in situ electrode cleaning and improve long-term electrode performance. Optimization of a hopper design and drainpipe location to collect and remove flaking precipitates and mitigate maintenance issues. Design of an automated salt injection system to guarantee sufficient chloride levels for producing adequate chlorine residuals for consistent disinfection.

Full Text

Duke Authors

Cited Authors

  • Varigala, S; Krishnaswamy, S; Lohia, CP; Hegarty-Craver, M; Grego, S; Luettgen, M; Cid, CA

Published Date

  • January 2021

Published In

Volume / Issue

  • 93 / 1

Start / End Page

  • 148 - 158

PubMed ID

  • 32516457

Pubmed Central ID

  • PMC7818490

Electronic International Standard Serial Number (EISSN)

  • 1554-7531

International Standard Serial Number (ISSN)

  • 1061-4303

Digital Object Identifier (DOI)

  • 10.1002/wer.1374

Language

  • eng