Bioremediation of pit toilet sewage

Rao, Sudhakar M and Arkenadan, Lydia and Mogili, Nitish V and Atishaya, Saksham K and Anthony, Priscilla (2017) Bioremediation of pit toilet sewage. In: Journal of Environmental Engineering and Science, 12 (2). pp. 26-33. ISSN 1496-2551

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Abstract

The paper examines the efficacy of anaerobic, aerobic and denitrification reactions in reducing organic carbon (C), ammonium and nitrate concentrations in pit toilet sewage. The anaerobic character of pit toilet sewage causes nitrogen (N) to prevail as ammonium rather than as nitrate ions. Anaerobic decomposition of organic carbon is initially resorted to reduce competition for ammonium oxidation during subsequent aerobic treatment of sewage. A mixture of air-dried cattle manure, sand and gravel is used as a biobarrier medium for nitrate reduction. Cattle manure serves as an affordable organic carbon source; sand particles act as a medium for attached bacterial growth, while gravel improves the permeability of the barrier. Batch tests showed that anaerobic reactions reduce chemical oxygen demand (COD) concentration in pit toilet sewage by 85%. Comparatively, aerobic reactions reduce ammonium concentration in sewage by 77% through assimilation, nitrification and adsorption; 6-10 h of contact between the biobarrier mix and nitrate leads to acceptable levels of denitrification (residual nitrate concentration < 45 mg/l). A modified twin-pit toilet that facilitates anaerobic decomposition of sewage in the first pit and aerobic treatment and denitrification of sewage in the second pit is constructed at Mulbagal town, Karnataka, India.

Item Type:	Journal Article
Publication:	Journal of Environmental Engineering and Science
Publisher:	ICE Publishing
Additional Information:	The Copyright of this article belongs to the ICE Publishing
Keywords:	Bioremediation; Denitrification; Fertilizers; Gravel; Manures; Mining laws and regulations; Nitrates; Organic carbon; Pollution; Sewage treatment; Aerobic treatment; Ammonium concentrations; Ammonium oxidation; Anaerobic decomposition; Anaerobic reactions; Environment; Nitrate concentration; Nitrate reduction; Chemical oxygen demand
Department/Centre:	Division of Mechanical Sciences > Centre for Sustainable Technologies (formerly ASTRA) Division of Mechanical Sciences > Civil Engineering UG Programme
Date Deposited:	15 Jun 2022 05:52
Last Modified:	15 Jun 2022 05:52
URI:	https://eprints.iisc.ac.in/id/eprint/73558

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