scholarly journals A Holistic Review on Biomass Gasification Modified Equilibrium Models

Energies ◽  
2019 ◽  
Vol 12 (1) ◽  
pp. 160 ◽  
Author(s):  
Sérgio Ferreira ◽  
Eliseu Monteiro ◽  
Paulo Brito ◽  
Cândida Vilarinho
Keyword(s):  
Mathematical Models ◽  
Thermodynamic Equilibrium ◽  
Model Prediction ◽  
Biomass Gasification ◽  
Correction Factors ◽  
Equilibrium Models ◽  
Gasification Process ◽  
Empirical Correction ◽  
Holistic Review ◽  
Almost All

Biomass gasification is realized as a settled process to produce energy in a sustainable form, between all the biomass-based energy generation routes. Consequently, there are a renewed interest in biomass gasification promoting the research of different mathematical models to enlighten and comprehend gasification process complexities. This review is focused on the thermodynamic equilibrium models, which is the class of models that seems to be more developed. It is verified that the review articles available in the literature do not address non-stoichiometric methods, as well as an ambiguous categorization of stoichiometric and non-stoichiometric methods. Therefore, the main purpose of this article is to review the non-stoichiometric equilibrium models and categorize them, and review the different stoichiometric equilibrium model’s categorization available in the literature. The modeling procedures adopted for the different modeling categories are compared. Conclusion can be drawn that almost all equilibrium models are modified by the inclusion of empirical correction factors that improves the model prediction capabilities but with loss of generality.

Mathematical Modeling of a Biomass Steam Gasifier—A Modified Equilibrium Approach

2018 ◽  
Vol 140 (4) ◽  
Author(s):  
Thomas Gröbl ◽  
Heimo Walter
Keyword(s):  
Mathematical Modeling ◽  
Mathematical Models ◽  
Present Article ◽  
Equilibrium Model ◽  
Conversion Process ◽  
Thermochemical Conversion ◽  
Equilibrium Models ◽  
Gasification Process ◽  
Equilibrium Approach ◽  
Made In

A large potential is contributed to the energetic utilization of biomass, whereby thermochemical gasification seems to be especially interesting. In order to contribute to a better understanding of the thermochemical conversion process in the gasifier, mathematical models are used. An intensive effort is made in development of mathematical models describing the gasification process and a large number of models, considerably differing in their degree of simplification, and their applications are reported in literature. In the present article, a brief review of models applied, mainly focused on equilibrium models, is provided and a robust and flexible modified stoichiometric equilibrium model, for modeling a novel gasifier, is presented.

scholarly journals Biomass to Syngas: Modified Non-Stoichiometric Thermodynamic Models for the Downdraft Biomass Gasification

Energies ◽  
2020 ◽  
Vol 13 (21) ◽  
pp. 5668
Author(s):  
Hafiz Muhammad Uzair Ayub ◽  
Sang Jin Park ◽  
Michael Binns
Keyword(s):  
Crop Residues ◽  
Biomass Gasification ◽  
Thermochemical Conversion ◽  
Equilibrium Models ◽  
Gaseous Fuels ◽  
Gasification Process ◽  
Model Predictions ◽  
Experimental Values ◽  
Solid Biomass ◽  
Stoichiometric Models

Biomass gasification is the most reliable thermochemical conversion technology for the conversion of biomass into gaseous fuels such as H2, CO, and CH4. The performance of a gasification process can be estimated using thermodynamic equilibrium models. This type of model generally assumes the system reaches equilibrium, while in reality the system may only approach equilibrium leading to some errors between experimental and model results. In this study non-stoichiometric equilibrium models are modified and improved with correction factors inserted into the design equations so that when the Gibbs free energy is minimized model predictions will more closely match experimental values. The equilibrium models are implemented in MatLab and optimized based on experimental values from the literature using the optimization toolbox. The modified non-stoichiometric models are shown to be more accurate than unmodified models based on the calculated root mean square error values. These models can be applied for various types of solid biomass for the production of syngas through biomass gasification processes such as wood, agricultural, and crop residues.

Dynamic Modeling for Temperature Prediction in a Fluidized Bed Biomass Gasification Process

2021 ◽  
Author(s):  
Ibtihaj Khurram Faridi ◽  
Evangelos Tsotsas ◽  
Wolfram Heineken ◽  
Marcus Koegler ◽  
Abdolreza Kharaghani
Keyword(s):  
Fluidized Bed ◽  
Dynamic Modeling ◽  
Biomass Gasification ◽  
Temperature Prediction ◽  
Gasification Process

scholarly journals Integrating LCA with Process Modeling for the Energetic and Environmental Assessment of a CHP Biomass Gasification Plant: A Case Study in Thessaly, Greece

Eng ◽  
2020 ◽  
Vol 1 (1) ◽  
pp. 2-30
Author(s):  
Ioannis Voultsos ◽  
Dimitrios Katsourinis ◽  
Dimitrios Giannopoulos ◽  
Maria Founti
Keyword(s):  
Life Cycle Assessment ◽  
Life Cycle ◽  
Moisture Content ◽  
Process Simulation ◽  
Energy Savings ◽  
Biomass Gasification ◽  
Lower Efficiency ◽  
Technical Parameters ◽  
Gasification Process ◽  
Gasification Plant

The energetic and environmental performance of a cogeneration biomass gasification plant, situated in Thessaly, Greece is evaluated via a methodology combining process simulation and Life Cycle Assessment (LCA). Initially, the gasification process of the most common agricultural residues found in the Thessaly region is simulated to establish the effect of technical parameters such as gasification temperature, equivalence ratio and raw biomass moisture content. It is shown that a maximum gasification efficiency of approximately 70% can be reached for all feedstock types. Lower efficiency values are associated with increased raw biomass moisture content. Next, the gasifier model is up-scaled, achieving the operation of a 1 MWel and 2.25 MWth cogeneration plant. The Life Cycle Assessment of the operation of the cogeneration unit is conducted using as input the performance data from the process simulation. Global Warming Potential and the Cumulative Demand of Non-Renewable Fossil Energy results suggest that the component which had the major share in both impact categories is the self-consumption of electricity of the plant. Finally, the key conclusion of the present study is the quantification of carbon dioxide mitigation and non-renewable energy savings by comparing the biomass cogeneration unit operation with conventional reference cases.

scholarly journals Fitting mathematical models to lactation curves from holstein cows in the southwestern region of the state of Parana, Brazil

2015 ◽  
Vol 87 (1) ◽  
pp. 503-517 ◽  
Author(s):  
Abílio G.T. Ferreira ◽  
Douglas S. Henrique ◽  
Ricardo A.M. Vieira ◽  
Emilyn M. Maeda ◽  
Altair A. Valotto
Keyword(s):  
Mathematical Models ◽  
Milk Production ◽  
Information Criterion ◽  
The State ◽  
Holstein Cows ◽  
Suitable Model ◽  
Almost All ◽  
Quality Of Fit ◽  
Wood Model

The objective of this study was to evaluate four mathematical models with regards to their fit to lactation curves of Holstein cows from herds raised in the southwestern region of the state of Parana, Brazil. Initially, 42,281 milk production records from 2005 to 2011 were obtained from "Associação Paranaense de Criadores de Bovinos da Raça Holandesa (APCBRH)". Data lacking dates of drying and total milk production at 305 days of lactation were excluded, resulting in a remaining 15,142 records corresponding to 2,441 Holstein cows. Data were sorted according to the parity order (ranging from one to six), and within each parity order the animals were divided into quartiles (Q25%, Q50%, Q75% and Q100%) corresponding to 305-day lactation yield. Within each parity order, for each quartile, four mathematical models were adjusted, two of which were predominantly empirical (Brody and Wood) whereas the other two presented more mechanistic characteristics (models Dijkstra and Pollott). The quality of fit was evaluated by the corrected Akaike information criterion. The Wood model showed the best fit in almost all evaluated situations and, therefore, may be considered as the most suitable model to describe, at least empirically, the lactation curves of Holstein cows raised in Southwestern Parana.

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