Comparative Life Cycle Assessment of Water Disinfection Processes Applicable in Low-Income Settings

Access to safe, sufficient water for health and sanitation
is a
human right, and the reliable disinfection of water plays a critical
role in addressing this need. The environmental impact and sustainability
of water disinfection methods will also play a role in overall public
health. This study presents an investigation of the environmental
life cycle impacts of four ultraviolet disinfection systems utilizing
ambient solar radiation directly and indirectly for water disinfection
in comparison to chlorination and water delivery for application in
low-income settings. Product inspection and existing literature were
used to define a life cycle functional unit of 1 m3 of
water for each system, which allowed quantification of material use,
infrastructure requirements, and life cycle of the original components
of each system and those needed to keep them operational for the studied
lifespans (1, 5, 10, and 20 years) and scales (30, 100, 500, and 1000
L per day). For all studied cases, chlorine had the lowest impact
in all impact categories, but end-user acceptance of chlorine in some
settings is low, driving interest in low-impact alternatives. Disinfection
based on low-pressure mercury lamps had the next lowest normalized
impact in most categories and may represent a viable alternative,
particularly for long-term (10+ years), high production (500+ liters
per day) scenarios.