Decentralized treatment and recycling of greywater from a school in rural India

Abstract

Rural areas in developing countries face the twin challenges of water scarcity and risk of groundwater contamination due to lack of water treatment options. A decentralized greywater treatment system for reuse is an option that addresses both of these challenges. This study reports the performance of a decentralized greywater treatment and reuse system which was constructed and operated for over 12 months in a government-managed school in rural India. The handwash and kitchen wash wastewater streams were treated separately due to differences in the initial greywater characteristics. The treatment stages included pre-treatment using screens and grease traps, slow sand biofiltration combined with anaerobic sludge bioreactor, and aeration before the final ozone-based disinfection stage. The treated water at the end of all these stages was used for toilet-flushing in the school. The treatment system was operated for one year and sampling was performed to investigate the system performance. The overall treatment system showed removal efficiencies of 99 %, 98 %, 66 %, 73 %, 98 %, 96 % and >99.99 % for the parameters of turbidity, total suspended solids, nitrate, total phosphorus, biological oxygen demand (5 days), chemical oxygen demand and fecal coliform respectively. This study quantifies the performance of each subsystem and demonstrates for the first time that a decentralized greywater treatment can be operated effectively and economically in a rural Indian setting.

Granular media filtration for on-site treatment of greywater: A review

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Evaluating the performance of horizontal sub-surface flow constructed wetlands: A case study from southern India

“…45 " 44 "" %; 76 ! 34 " 03 "" +) located in Berambadi village, Chamarajanagar district, Karnataka (Subramanian et al, 2020). The area receives an annual rainfall of 915 mm and has an average annual temperature of 22.9 ºC (Sekhar, 2016).…”

Scenario-based life-cycle cost assessment to support sustainable investment in rural communal sanitation facilities: application to a school-based sanitation facility

“…The data and analysis presented here were collected throughout the design, construction, and post-construction phase of a decentralised wastewater treatment (DWWT) and sanitation facility in the Berambadi village school located in a part of the Chamarajanagar district that is 5 h away from any major city in the State of Karnataka, India (Figure 1) (Subramanian et al 2020). This project was funded by the Hydronation International Initiative of the Scottish Government as part of a wider effort to support research and innovation that contributes to progress towards SDG6.…”