Impact of waste segregation on leachate characteristics in semi-aerobic landfills: a pilot-scale evaluation for sustainable waste management.

This study evaluates the effects of different residual waste compositions, derived from simulated material recovery scenarios, on leachate quality and waste stabilization in pilot-scale semi-aerobic landfills. Unlike previous studies that examined semi-aerobic landfill performance using waste streams with fixed compositions, this study investigates how waste segregation-driven changes in residual waste composition affect leachate characteristics. Three bioreactors representing recovery levels of 0%, 25%, and 50% were operated using municipal solid waste from Lima, Peru, and monitored over an 18-week period. Key physical and chemical parameters-such as temperature, settlement, pH, conductivity, BOD5, COD, total solids, and volatile solids-were monitored. Results showed that while segregation did not significantly affect organic load parameters or conductivity, it contributed to lower turbidity levels. The findings demonstrate that semi-aerobic landfill performance remained robust across different residual waste compositions while providing novel pilot-scale evidence on the relationship between waste segregation and leachate quality. This study addresses a knowledge gap relevant to regions undergoing transitions toward circular economy.