A general model for air gasification of heterogenous municipal solid waste

Abstract

Sustainable management of municipal solid waste (MSW) is crucial due to its huge volume and cash flow. Among the different waste-to-energy solutions, gasification is considered an interesting option compared to incineration, which is the most common technology to valorise MSW, because of higher efficiency, lower environmental impacts, and producing hydrogen or other biofuel and biochemical products. However, mechanical–biological treatment of MSW results in heterogenous materials mainly composed of plastics, paper, and textiles, which troubles a reliable study of gasification. Hence, a flexible model of a fluidized bed air gasifier is developed in Aspen Plus in this work based on the experimental data from the literature to estimate the syngas properties from residual MSW of composting facilities.The developed model gives a low heating value (LHV) of the syngas in the range 4.2–7.3 MJ/Nm3 considering the characteristics of the residual MSW from a real composting facility, which is in line with the experimental values reported in the literature. Furthermore, a sensitivity analysis is performed varying the composition of the residual waste from the mechanical–biological treatment to support preliminary feasibility analyses of energy production from heterogeneous materials. The results showed a good capability of the model in predicting the energy performance of the fluidized bed gasifiers varying feedstock materials and equivalence ratios.