Energy, exergy and economic analysis of a poly-generation system combining sludge pyrolysis and medical waste plasma gasification

Abstract

To optimize the processes of treating medical waste and pyrolyzing sludge, we propose a new integrated system that combines plasma gasification for medical waste treatment, combined cycle power generation, and sludge pyrolysis. The medical waste is first incinerated, and then the synthesis gas from plasma gasification powers a gas turbine to generate electricity in this integrated system. The gas turbine's exhaust gas heats steam and feedwater from the HRSG to achieve a combined gas-steam cycle. Simultaneously, turbine exhaust steam energizes sludge pyrolysis, allowing for efficient conversion of medical waste into electricity in an eco-friendly manner. A hybrid design study was conducted using different methods, including energy, exergy, and economic analysis. The study revealed that the medical waste-to-energy system integration has the potential to attain 66.31% energy efficiency and 66.70% exergy efficiency. Moreover, the medical waste-electricity project has a dynamic payback period of 2.46 years and a relative net present value of 38,949.91k$. These outcomes suggest that this innovative concept is practical, advantageous, and has excellent potential for further development in the field of waste-to-energy conversion.