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In the past two decades, advancements in thermochemical technologies have improved biomass gasification for distributed power generation, enhancing efficiency, scalability, and emission control. This study aims to optimize syngas production from biomass gasification by comparing two computational models: a quasi-equilibrium thermodynamic model implemented in Aspen Plus and an artificial neural network (ANN) model. Operating at 850 °C with varying steam-to-biomass (S/B) ratios, both models were validated against experimental data. Results show that hydrogen concentration in syngas increased from 19.96% to 43.28% as the S/B ratio rose from 0.25 to 0.5, while carbon monoxide concentration decreased from 24.6% to 19.1%, consistent with the water–gas shift reaction. The ANN model provided rapid predictions, showing a mean absolute error of 3% for hydrogen and 2% for carbon monoxide compared to experimental data, though it lacks thermodynamic constraints. Conversely, the Aspen Plus model ensures mass and energy balance compliance, achieving a cold gas efficiency of 95% at an S/B ratio of 0.5. A Multivariate Statistical Analysis (MVA) further clarified correlations between input and output variables, validating model reliability. This combined modelling approach reduces experimental costs, enhances gasification process control and offers practical insights for improving syngas yield and composition. [ABSTRACT FROM AUTHOR]

The present paper deals with the process analysis of a biomass-to-electricity industrial plant. Starting from the process simulation by means of Aspen Plus software, this work discusses the technical, environmental, and economic performance of a biomass integrated gasification combined cycle (BIGCC) power plant. To enable a safe integration, a mid-to-high temperature cleaning system has been implemented to target reference inorganic contaminants that hinder the use of syngas in commercial applications, namely hydrochloric acid, and hydrogen sulphide. The actual effectiveness of the overall system has been evaluated by performing a holistic assessment of a 7 MWe BIGCC using hazelnut shells as biomass and equipped with sorbent reactors to remove the target contaminants before entering the power generation section of the plant. [ABSTRACT FROM AUTHOR]

Global warming, along with increasing global energy demands, has led to the need for a sustainable and low-carbon-based energy economy. In addition to renewable energy technologies, such as biomass, solar, hydro, and wind, another possible strategy to mitigate climate change is the capture/conversion and recycling of CO2. In recent years, many methods for both CO2 capture (mainly adsorption, absorption, and membrane) and conversion (many electrolysis, catalyst, and plasma) have been investigated. Conversion technology is less studied but seems to be very promising. Within that, non-thermal plasma technology has received much interest because it works at low temperatures and atmospheric pressure, and there is no need for high temperature and high electricity consumption, which are typical of the catalyst and electrolysis conversion processes, respectively. Therefore, in order to optimize this emerging technology, simulative kinetic models have been developed with the aim of maximizing both energy efficiency and CO2 conversion. In the present paper, an overview of the most common non-thermal plasma technologies was carried out to highlight the advantages and disadvantages of each method. Then, an overview of the most significant kinetic models available in literature was carried out to point out the main reactions occurring during CO2 conversion and also the parameters that most affect the performance of a plasma reactor during CO2 conversion. Then, a brief recap of the literature available on economic studies of the plasma process is given. [ABSTRACT FROM AUTHOR]

Carbon Capture and Utilization (CCU) is a viable solution to valorise the CO2 captured from industrial plants' flue gas, thus avoiding emitting it and synthesizing products with high added value. On the other hand, using CO2 as a reactant in chemical processes is a challenging task, and a rigorous analysis of the performance is needed to evaluate the real impact of CCU technologies in terms of efficiency and environmental footprint. In this paper, the energetic performance of a DME and methanol synthesis process fed by 25% of the CO2 captured from a natural gas combined cycle (NGCC) power plant and by the green hydrogen produced through an electrolyser was evaluated. The remaining 75% of the CO2 was compressed and stored underground. The process was assessed by means of an exergetic analysis and compared to post-combustion Carbon Capture and Storage (CCS), where 100% of the CO2 captured was stored underground. Through the exergy analysis, the quality degradation of energy was quantified, and the sources of irreversibility were detected. The carbon-emitting source was a 189 MW Brayton–Joule power plant, which was mainly responsible for exergy destruction. The CCU configuration showed a higher exergy efficiency than the CCS, but higher exergy destruction per non-emitted carbon dioxide. In the DME/methanol production plant, the main contribution to exergy destruction was given by the distillation column separating the reactor outlet stream and, in particular, the top-stage condenser was found to be the component with the highest irreversibility (45% of the total). Additionally, the methanol/DME synthesis reactor destroyed a significant amount of exergy (24%). Globally, DME/methanol synthesis from CO2 and green hydrogen is feasible from an exergetic point of view, with 2.276 MJ of energy gained per 1 MJ of exergy destroyed. [ABSTRACT FROM AUTHOR]

Summary: Any possible sustainable way to meet climate targets relies on carbon capture and storage (CCS). Many literature works focus on the comparison between CCS approaches and technologies, also utilizing thermodynamic analysis to evaluate the inefficiencies of the processes, to understand and locate the additional consumption of primary energy, and, eventually, to provide a rigorous instrument for comparison. In this article, we provide a comprehensive assessment of the energy consumption and exergy destruction in CCS and propose a general and novel methodology that allows to unify the various available approaches. According to our calculations, the lowest energy and fuel penalties can be achieved with precombustion capture schemes. The minimum values found are around 8% to 9% for energy penalty, very close to the minimum achievable penalty of 3%. In addition, this results into a fuel penalty of 10% against the thermodynamic limit of 3.5% to 4%. The postcombustion scheme shows slightly worse performance that can be improved with mechanical energy‐driven processes (such as cryogenic separation or adsorption process) that, if optimized, can reach a work of separation quite below 1 MJ/kg CO2. The methodology and results can be useful for engineers as well as for decision‐makers to evaluate the optimal technological pathways of decarbonization. [ABSTRACT FROM AUTHOR]