Environmental performance of waste incineration plants with biogasification and methanation

Abstract

Methanation is a promising method of utilizing CO₂ derived from waste incineration, and can promote decarbonization of the city gas and heat utilization sectors by replacing fossil-based methane with carbon-neutral synthetic methane derived from waste. In this study, models of waste incineration plants with biogasification and methanation were built, and sensitivity analysis was conducted to evaluate the methane production potential and environmental performance. The methane production of the models with methanation was about 1.4 to 1.9 times that of the model with biogasification only. If waste incineration plants with biogasification and methanation are built to meet the cumulative demand for plant reconstruction by 2050 in the Kinki region, they can produce up to about 150 million Nm³ of methane per year. The model in which hydrogen required for methanation is produced from surplus electricity and the model in which hydrogen is procured externally without restrictions show advantage in different situations depending on the emission factor of grid electricity and other factors.