Aspen Plus has become one of the most common process simulation tools for both academia and industrial applications In the last decade, the number of the papers on Aspen Plus modeling of biomass gasification has significantly increased This review focuses on recent developments and studies on modeling biomass gasification in Aspen Plus including key aspects such as tar formation and model validation Accordingly, challenges in modeling due to specific assumptions and limitations will be highlighted to provide a useful basis for researchers and end-users for further process modeling of biomass gasification in Aspen Plus

https://onlinelibrary.wiley.com/doi/epdf/10.1002/ceat.202000068

Challenges and Opportunities of Modeling Biomass Gasification in Aspen Plus: A Review

Wet organic waste treatment via hydrothermal processing: A critical review.

Bioenergy production is one of the most reliable strategies for replacing fossil fuels and reducing CO2 emissions. Gasification-based bioenergy generation has been extensively studied; however, it is still facing the challenges of limited energy efficiencies, especially upon small-scale development. Concentrated solar thermochemical gasification of biomass (CSTGB) where the endothermic reactions of gasification are driven by concentrated solar thermal energy serves as a promising solution to improve the efficiency of gasification. This review summarized recent development in modeling concentrated solar thermochemical gasification of biomass, the method of concentrated solar thermal for gasification, and applications and development of concentrated solar thermal biomass gasification. The influences of operating parameters toward the performance of the technology were studied, which determine the optimum parameters for maximizing the energy conversion efficiency of the technology. CSTGB could improve the utilization of biomass feedstocks and the total energy efficiency by 30% and 40%, respectively by effectively storing solar energy in the producer gas as compared to conventional gasification.

Concentrated solar thermochemical gasification of biomass: Principles, applications, and development

Experimental investigation of syngas composition variation along updraft fixed bed gasifier

Carbon gasification in molten alkali carbonate salts over CO2 is a process to produce gaseous fuels with mitigating the greenhouse effect. Alkali carbonate salts can facilitate Boudouard reaction, which is difficult to occur even at high reaction temperature if the catalyst is absent. Alkali carbonate allows easily carbon−CO2 contact by changing the reaction interface from gas-solid to gas-liquid. This review focused on CO2 utilization for alkali carbonate gasification and biomass/coal co-gasification. CO2 gasification of biomass and coal with the alkali carbonate salts enhances the carbon conversion rate and CO yield. Furthermore, alkali carbonate salts gasification of biomass and coal could reduce reaction temperature, activation energy, and tar formation in the product gas. The factors that influence the carbon conversion rate were discussed, such as reaction temperature, CO2 concentration, alkali carbonate addition, and char feeding mode. On the other hand, blending coal with biomass is considered as potential fuel base for CO2 co-gasification and displays an advantage for improving the coal char reactivity. The alkali and alkaline earth metals (AAEMs) present in biomass ash acted as a natural catalyst to increase the coal reactivity and CO production. The catalytic effect in the co-gasification enhances by raising the percentage of biomass in the blend. In contrast, the inhibiting effect in co-gasification could be attributed to silica and alumina reactions with AAEMs to form aluminosilicates complexes.

A brief review of CO2 utilization for alkali carbonate gasification and biomass/coal co-gasification: Reactivity, products and process

Oxygen-enriched air gasification of biomass materials for high-quality syngas production

The adsorption mechanism of Cd2+ on different cleavage planes of montmorillonite was investigated using density functional theory (DFT) calculations and molecular dynamics (MD) simulations. The most stable adsorption energies of Cd2+ on the (001) and (010) surfaces were −88.74 kJ/mol and −283.55 kJ/mol, respectively. On the (001) surface, Cd2+ was adsorbed on the centre of the silicon–oxygen ring by electrostatic interactions, whereas on the (010) surface, Cd2+ was adsorbed between two ≡Al–OH groups and formed two covalent bonds with O, which was mainly due to the interaction between the Cd s and O p orbitals. Upon the partial substitution of Na+ by Cd2+, Cd2+ was adsorbed on the (001) surface as inner-sphere surface complexes, with a hydration number of 5.01 and a diffusion coefficient of 0 m2/s. Whereas, when Cd2+ completely replaced Na+, part of the Cd2+ moved from the inner-sphere surface complexes to the outer-sphere surface complexes owing to its competitive adsorption. In this case, its hydration number became 6.05, and the diffusion coefficient increased to 1.83 × 10−10 m2/s. This study provides the theoretical background necessary for the development of montmorillonite-based adsorbents.

/pdf/understanding-cd2-adsorption-mechanism-on-montmorillonite-3752b3fl.pdf

J. Du

Papers

Oxygen-enriched air gasification of biomass materials for high-quality syngas production

Understanding Cd2+ Adsorption Mechanism on Montmorillonite Surfaces by Combining DFT and MD