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Gasification is a multiphase process that converts the solid fuels into useful synthetic gas. Despite the potential of biomass gasification as a clean technique to produce a high caloric value syngas, it is not as well looked upon as its advantages suggest. In the present study, an ASPEN plus model of biomass gasification was developed with considering the kinetics of the reactions and tar cracking mechanism. Firstly, the model was validated against the experimental data in the literature. Next, a parametric study was done to investigate and evaluate the performance and produced gas composition of air–steam gasification of biomass. The effect of various operational parameters, such as the reaction temperature, equivalence ratio (ER) and steam/biomass ratio (S/B) on the gas product composition, products yield and the gasifier performance was investigated. The results showed that the increase of reaction temperature not only can enhance the H2 content in the gas stream, but inhibit the formation of tar. The achieved optimal conditions for production of maximum H2 content (16.18 vol %) were as follows: reaction temperature of 800 °C, S/B of 0.8 and ER of 0.211. [ABSTRACT FROM AUTHOR]

Steam gasification is considered as a clean route to produce H2-rich syngas and other energy products such as methanol. However, environmental issues and technical problems related to tar formation have become serious challenges in commercialization of biomass gasification. In the present study, an ASPEN plus® model was developed to convert the municipal solid waste (MSW) into a H2-rich syngas in the presence of steam as gasification agent. Different operation conditions, temperatures (750–900 °C) and steam flow rates (SFRs) (0.138–0.312 kg/h) were studied for their effects on the gas compositions, product yields and gasifier performances. The results indicated that the H2 content increased by increasing the gasification temperature. When the temperature was raised from 750 to 900 ℃, the gas yield rose by 29.8% due to the enhanced endothermic reactions. Furthermore, with the increase in gasification temperature, the tar yield declined with respect to the tar cracking reaction. The addition of steam significantly improved H2 production by simultaneously promoting the water–gas shift reaction and tar cracking reactions. To summarize, the present model provided positive predictions of the MSW gasification in terms of tar elimination and H2-rich syngas production. [ABSTRACT FROM AUTHOR]