Scenarios for carbon capture integration in a waste-to-energy plant

Abstract

In this work, the performance of an amine-based post-combustion carbon capture system using MEA (monoethanolamine) integrated to a Waste-to-Energy (WtE) plant is studied. WtE plants are affected by fluctuations at different time-scales, due to changes in waste properties as well as variations in district heat demand. A dynamic model of the combined plant is used to study the effect of flue gas fluctuations on capture plant operation, and the effect of integrating the capture plant into the WtE plant.When the two plants are considered separately, the heat requirement of the capture plant corresponds to 27% of the nominal thermal capacity of the WtE plant. When integrating the two plants, steam extraction from the boiler drum to provide the heat necessary to the capture plant reduces the power and district heat production of the WtE plant by 30% and 6% respectively, while extraction from the turbine causes a reduction of 8% and 12%. By modifying the condensers’ temperature, it is possible to maintain 96% of the original district heat production. By performing carbon capture only when excess heat is available, it is possible to capture 47% of the CO2 emitted by the WtE plant, while reducing the power production by only 5%.