Fate and Remediation of Ammonium-n In Pit Toilet Blackwater

Abstract

Pit toilets satisfy the sanitation requirement in regions with no access to piped sewerage facilities. Black water discharged from pit toilets is a major source of groundwater pollution. The primary focus of the thesis is to understand the fate of ammonium-N in blackwater generated in pour flush pit toilets, in blackwater contaminated soils in vicinity of leach pits that are subject to moisture evaporation and lastly develop a methodology to reduce nitrate contamination of aquifers by blackwater released from leach pits of pour flush toilets. In the first part of the study, the characteristics of black water from a pour flush pit toilet located in Mulbagal town, Karnataka, India, for nitrogenous constituents and other physico-chemical parameters are examined. The impact of moisture evaporation on fate of ammonium-N reactions in blackwater contaminated soils is next investigated in this study. Methodology for in-situ removal of soluble N fraction from blackwater in leach pit of pit toilet is developed. Guided by results from laboratory experiments, design for modified twin pit toilet is proposed that reduces the contamination load on groundwater