Papers by Eliseu Monteiro
Biomass pre-treatment techniques for the production of biofuels using thermal conversion methods – A review
Energy Conversion and Management
Heat Transfer Simulation in the Mould With Generalized Curvilinear Formulation
Residual Stress, Fitness-For-Service, and Manufacturing Processes, 2003
A large number of mould manufactures need to reduce cost production. In fact, the production of a... more A large number of mould manufactures need to reduce cost production. In fact, the production of a part by foundry techniques is influenced by its complex geometry configuration, which affects the solidification conditions and subsequent cooling. The simulation of heat transfer phenomena between metal and mould helps to reduce or even eliminate the need of corrective alterations of the mould. This approach will help to reduce its cost. The main objective of this paper is to describe the development of a finite volume method in order to simulate the heat transfer phenomena during the phase change process. Because of the mould design complexity, the finite volume is described using the generalized curvilinear formulation.Copyright ?? 2003 by ASME
Energies, 2019
The first part of the current reported work presents experimental results of brewers’ spent grain... more The first part of the current reported work presents experimental results of brewers’ spent grains gasification in a pilot-scale downdraft gasifier. The gasification procedure is assessed through various process characteristics such as gas yield, lower heating value, carbon conversion efficiency, and cold gas efficiency. Power production was varied from 3.0 to 5.0 kWh during the gasification experiments. The produced gas was supplied to an internal combustion engine coupled to a synchronous generator to produce electricity. Here, 1.0 kWh of electricity was obtained for about 1.3 kg of brewers’ spent grains pellets gasified, with an average electrical efficiency of 16.5%. The second part of the current reported work is dedicated to the development of a modified thermodynamic equilibrium model of the downdraft gasification to assess the potential applications of the main Portuguese biomasses through produced gas quality indices. The Portuguese biomasses selected are the main represent...
Lecture Notes in Electrical Engineering, Jun 3, 2018
Gasification of wastes is considered a promising alternative for energy generation due to its low... more Gasification of wastes is considered a promising alternative for energy generation due to its lower environmental impacts when compared with conventional landfilling and incineration. Valorisation of such wastes improves sustainability of resource management and of energy production. However, an appropriate characterisation of wastes in terms of physical and chemical properties is essential for the prediction of their behaviour during gasification, allowing to identify possible problems for the environment and installed equipment and also to define which materials present a greater energy potential. This study aimed to characterise 10 different fractions from municipal, construction and demolition wastes received in different fluxes by a Portuguese waste management company. These fractions included wood (44.83 wt%), plastic (22.15 wt%), paper/card (0.04 wt%), mixtures of paper and plastic (14.67 wt%) and sewage sludge (18.31 wt%). For this purpose, determination of density, proximate and ultimate analysis, higher heating value (HHV), thermogravimetric profiles and inorganic composition of ashes were performed for each fraction. Analysis revealed that plastics and their mixtures with paper/card possess the highest HHV's (25-45 MJ/kg db), thus exhibiting a greater capacity for energy production. High levels of ashes found in dried sewage sludge (50 wt % db) indicate that a lot of by-product will be generated after gasification, possibly increasing the treatment costs. A gasification unit operating at 50 kg/h and admitting a mixture of all these wastes would generate 109.7 kW of total power, having capacity to receive more waste fluxes along the year.
Energies, Nov 27, 2023
Hydrogen produced sustainably has the potential to be an important energy source in the short ter... more Hydrogen produced sustainably has the potential to be an important energy source in the short term. Biomass gasification is one of the fastest-growing technologies to produce green hydrogen. In this work, an air-blown gasification model was developed in Aspen Plus ® , integrating a water-gas shift (WGS) reactor to study green hydrogen production. A sensitivity analysis was performed based on two approaches with the objective of optimizing the WGS reaction. The gasifier is optimized for carbon monoxide production (Case A) or hydrogen production (Case B). A CO 2 recycling stream is approached as another intensification process. Results suggested that the Case B approach is more favorable for green hydrogen production, allowing for a 52.5% molar fraction. The introduction of CO 2 as an additional gasifying agent showed a negative effect on the H 2 molar fraction. A general conclusion can be drawn that the combination of a WGS reactor with an air-blown biomass gasification process allows for attaining 52.5% hydrogen content in syngas with lower steam flow rates than a pure steam gasification process. These results are relevant for the hydrogen economy because they represent reference data for further studies towards the implementation of biomass gasification projects for green hydrogen production.
Hydrogen supply chain: Current status and prospects
Energy Storage
In the current world energy scenario with rising prices and climate emergencies, the renewable en... more In the current world energy scenario with rising prices and climate emergencies, the renewable energy sources are essential for reducing pollution levels triggered by carbon‐based fuels. Hydrogen rises in the world energy scenario as an important non‐carbon‐based energy able to replace fossil fuels. For this reason, the rapid development of hydrogen‐related technology has been seen in recent years. This review paper covers hydrogen energy systems from fossil fuel‐based hydrogen production, biomass and power from renewable energy sources, to hydrogen storage in compressed gases, liquefied and solid materials, and hydrogen‐based power generation technology. It represents a quiet complete set of references that may be effective in increasing the prospects of hydrogen as a fuel in the coming years. The main conclusions drawn are that natural gas and coal supply nearly all of the current hydrogen. The commercially available technologies for hydrogen production are steam methane reforming...
Automotive plastic waste and olive pomace valorization using the pyrolysis process
Energy Reports
On the operating parameters for hydrogen-rich syngas production in a plasma co-gasification process of municipal solid wastes and polypropylene using a constrained model in Aspen plus
Journal of the Energy Institute
An Economic Case Study of Hydrogen Energy Storage
Austin Environmental Sciences, 2021
The use of hydrogen as an energy vector has been considered as one promising way to attend societ... more The use of hydrogen as an energy vector has been considered as one promising way to attend society decarbonization. Hydrogen can be used as a chemical to store electricity and as a fuel to electric fuel cell mobility. This work makes hydrogen production potential economical evaluation of 5 real solar photovoltaic installations intended primarily for self-consumption. The surplus electrical energy can be used to produce hydrogen, which will be used later as a form of energy, potentially in an application. That provides greater economic value. Hydrogen serves as an important career to the storage of energy and can be more interesting and competitive than a battery-based solution. The results show that the use of hydrogen is only economically viable for mediumsized installations, greater than 300MW and for the production of hydrogen for mobility.
Carbonisation as a pre-treatment for RDF wastes prior to gasification
Wastes: Solutions, Treatments and Opportunities III, 2019
A review on occupational risk in gasification plants processing residues of sewage sludge and refuse-derived fuel
Occupational Safety and Hygiene VI, 2018
Biomass gasification is realized as a settled process to produce energy in a sustainable form, be... more 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 nonstoichiometric 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 tha...
On the green hydrogen production through gasification processes: A techno-economic approach
Journal of Cleaner Production
Plasma gasification process using computational fluid dynamics modeling
Energy Reports
Performance assessment of the co-gasification for sustainable management of municipal solid waste: Moroccan Case
Energy Reports
In the quest of virtuous energy system, clean energy production poses important environmental, so... more In the quest of virtuous energy system, clean energy production poses important environmental, social, and financial challenges. Among the potentially useful energy carriers, hydrogen emerges as a serious alternative to fossil fuels. Hydrogen is a clean energy vector whose use is likely to undergo significant development in the medium and long term. This article describes the current situation of municipal solid waste generation and management in Morocco. Additionally, a co-gasification plant model for hydrogen production from municipal solid waste and biomass blends was developed in Aspen Plus. A parametric analysis was carried out to study the effect of various parameters such as the temperature of gasification and the steam to feedstock ratio on syngas composition. The main findings show an increase in hydrogen molar fractions for higher temperatures (optimal values being achieved for ∼750 • C) and steam to feedstock ratios ≥1.2. The present model of the co-gasification plant could be further improved by adding a water-gas-shift reactor. This process intensification technique can contribute to the production of sustainable alternatives to the actual predominant fossil-based fuels.
Optimizing the operating conditions for hydrogen-rich syngas production in a plasma co-gasification process of municipal solid waste and coal using Aspen Plus
International Journal of Hydrogen Energy
Numerical modeling of plasma gasification process of polychlorinated biphenyl wastes
Energy Reports, 2021
International Journal of Hydrogen Energy, 2019
h i g h l i g h t s A numerical model was developed to simulate plasma gasification of solid resi... more h i g h l i g h t s A numerical model was developed to simulate plasma gasification of solid residues. The effect of operational conditions on syngas was assessed for optimized results. Accurate predictions were seen, comparing numerical results with experimental data. A balance between plasma power, syngas quality and process efficiency must be set. Syngas with lower heating value of 7.5 MJ/Nm 3 was achieved.
Renewable Energy, 2019
The need to achieve renewable alternatives for energy production is pressing and new technologies... more The need to achieve renewable alternatives for energy production is pressing and new technologies have been developed. Biomass is a feasible feedstock for thermal conversion techniques like gasification. This technique converts carbonaceous fuels into energy, producing a synthetic gas (syngas) with further commercial uses such as electricity generation, fuels or the chemical industry among others. In this work, a numerical model was developed in order to optimize the experimental parameters in the gasification of agricultural residues. Hence, oxygen content (OC) in the gasifying agent, equivalence ratio (ER) and fluidization velocity were varied so as to assess the effect of each parameter in syngas quality. Lower ER favored higher CO and H 2 yields, enhancing also the lower heating value (LHV). Higher fluidization velocity also promoted these features, as well as gasification conversion efficiency (GCE) and carbon conversion efficiency (CCE). Higher OC in the gasifying agent improve syngas quality. The optimal gasification performance was achieved for OC ¼ 40%. The results obtained in this work are essential to describe scenarios relating to the potential use of agricultural residues as a source of energy via gasification.
Renewable Energy, 2019
This study is dedicated to present a reliable numerical methodology using Aspen Plus process simu... more This study is dedicated to present a reliable numerical methodology using Aspen Plus process simulator capable of performing a sensibility analysis of the downdraft gasification of Portuguese forest residues. Effects of critical parameters, including gasification temperature and steam-to-biomass ratio (SBR) on composition of the produced gas are discussed. The sensibility analysis is conducted using Aspen Plus simulator incorporating Fortran subroutines. The model is validated by experimental data and found to be in good agreement. The results of the sensibility analysis performed using air as gasification agent indicate that higher temperatures are favourable for a produced gas with higher hydrogen content and heating value. The simulation results also demonstrate that the use of steam as gasification agent allows increasing the hydrogen content and heating value of the produced gas in comparison to the use of air as gasifying agent. The knowledge of this data is decisive to the development of projects concerning the use of Portuguese forest residues as energy source.
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Papers by Eliseu Monteiro