Environmental assessment of sewage effluent disinfection system: electron beam, ultraviolet, and ozone using life cycle assessment

摘要

Purpose This study assesses the impacts of three different disinfection processes of sewage effluent, namely the electron beam (E-beam), ultraviolet (UV), and ozone systems, on the environment by using life cycle assessment (LCA). Methods The LCA employed was the comparative LCA which consists of three parts according to life cycle stages. Electricity consumption was the reference flow that can yield 99% disinfection efficiency for microorganisms present in a l×10~5 m~3day~（-1） sewage treatment plant effluent over 20 years. Results The comparison of the LCA results indicated that the environmental impact of the UV disinfection system was the lowest, followed by the E-beam and ozone disinfection systems. The key issues of the E-beam, UV, and ozone disinfection systems are electricity consumption and SF_6 usage, electricity consumption and UV lamp, and electricity consumption and liquid oxygen feeding system, respectively. Conclusions Electricity consumption is the key input parameter that determines the LCA results.