Article
Green & Sustainable Science & Technology
Vincenzo Bianco, Mateusz Szubel, Beata Matras, Mariusz Filipowicz, Karolina Papis, Szymon Podlasek
Summary: This paper discusses the design optimization of an air manifold for biomass-fired batch boilers, focusing on reducing entropy generation and improving device performance. By comparing four different design options, a method to effectively reduce entropy generation is identified, and the acceptability of design improvements is confirmed through monitoring velocities and pressure drops.
Review
Engineering, Chemical
Hong Huang, Yan Gao, Hunan Chen, Yiying Wu, Jiayi Wang, Chenglong Yu, Jianlong Li, Changwei Zou
Summary: This work provides an overview of the fuel types, characteristics, and air pollutants emitted from the combustion of industrial biomass boilers. It identifies the deficiencies in existing research and suggests the need for further investigation into biomass fuel, combustion process, and emitted pollutants. The review serves as a scientific basis for accurately evaluating industrial biomass boilers and effectively preventing and controlling pollution.
Article
Thermodynamics
B. Rajh, M. A. Gomez, C. Alvarez-Bermudez, N. Cid, J. L. Miguez
Summary: This paper introduces two models for simulating packed bed biomass combustion, one based on a 1D experimental method and the other on an analytical 3D method. The performance of these models is tested through the simulation of a 60-kW wood pellet boiler under different operating conditions. The results show that both models have similar overall behavior, but the 1D model is more sensitive to the char oxidation correlations.
ENERGY CONVERSION AND MANAGEMENT
(2022)
Article
Chemistry, Physical
Qiang Lyu, Ruru Wang, Yongbo Du, Yinhe Liu
Summary: Co-firing NH3 in coal-fired power plants is a promising strategy for global decarbonization, but the contradiction between high temperature and low NOx emission limits its utilization. This study conducted 3-dimensional numerical simulations on coal/NH3 co-firing cases in a full-scale boiler, investigating the effects of NH3 blending ratio, O-2 enrichment combustion, and deep air-staging technology. The results show that the burnout properties of NH3 are good in the co-firing boiler, and higher NH3 blending ratio leads to lower furnace temperature. Enriching O-2 concentration can compensate for temperature decline, but results in increased NOx concentrations. Combining O-2 enrichment and deep air-staging combustion can create a high temperature and strong reducing atmosphere, reducing NO emissions and improving overall efficiency.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2023)
Article
Thermodynamics
Zhenhua Yuan, Zhichao Chen, Bo Zhang, Xuelin Gao, Jiawei Li, Yanyu Qiao, Zhengqi Li
Summary: In this study, the slagging trends in the pre-combustion chamber (PCC) under different excess air coefficients were investigated using CFD simulation. It was found that the collision rate, deposition rate, and sticking rate of particles on the PCC walls increased exponentially with the increase of excess air coefficient, indicating a rapid growth in wall abrasion. However, when the excess air coefficient was 0.3, the deposition rate and sticking rate of particles on the PCC walls were much larger due to the presence of a sizable annular recirculation zone, leading to the worst slagging trend. Therefore, it is recommended to adjust the excess air coefficient between 0.5 and 0.9 to improve the safety of boiler operation.
Article
Thermodynamics
Xianqiang Su, Lun Ma, Qingyan Fang, Chungen Yin, Huiyong Zhuang, Yu Qiao, Cheng Zhang, Gang Chen
Summary: The distribution of primary air along the grate length significantly affects combustion and pollutant formation behaviors in the furnace. Reasonable air supply facilitates complete combustion in both the fuel-bed and freeboard, and helps to suppress the formation of NO.
APPLIED THERMAL ENGINEERING
(2024)
Article
Thermodynamics
Marek Pronobis, Robert Wejkowski, Sylwester Kalisz, Szymon Ciukaj
Summary: The aim of this work is to analyze the feasibility of converting a pulverized coal boiler to 100% biomass combustion using torrefied PKS. By replacing hard coal with torrefied biomass, CO2 emissions can be practically eliminated, and the problem of coal shortages in Europe can be reduced. However, there are challenges to address such as boiler fouling, grinding new fuel, changing NOx emissions, and exhaust gas dew point. Measurements and calculations were conducted to assess the risks of slagging and fouling and to evaluate the potential use of Dunino halloysite for protection against corrosion. The results show that the combustion of PKS leads to higher flue gas temperatures compared to coal combustion.
Article
Chemistry, Physical
Mustafa Ilbas, Ozan Kekul, Abdulkadir Bektas, Serhat Karyeyen
Summary: In this study, the combustion of pure ammonia in a model combustor was investigated to explore ammonia-fueled applications. The effects of oxygen enrichment on flame characteristics, temperature profiles, and NO profiles during ammonia combustion were evaluated, and compared with the combustion of air-ammonia mixture. The results showed that the use of an oxidizer with 100% oxygen content provided better flame stability in pure ammonia combustion. The most stable flame for oxy-ammonia combustion was achieved with an excess oxygen coefficient of 1.0 or 1.2, and the lowest NO levels were observed under fuel-rich conditions. The air-ammonia combustion resulted in a significant decrease in temperature and NO emissions, but flame stabilities were unsatisfactory except under fuel-rich conditions. The oxy-enrichment condition is considered a promising method for pure ammonia combustion, provided that NO emissions can be optimized with NO reduction methods.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2022)
Article
Energy & Fuels
Seyed Morteza Mousavi, Hesameddin Fatehi, Xue-Song Bai
Summary: This paper presents a numerical study on flow, reactions, and NOx emissions from a biomass boiler, utilizing detailed reaction mechanisms and CFD simulations. The study identifies different pathways for NOx formation and evaluates the performance of the Selective Non-Catalytic Reduction (SNCR) method, showing a reduction of up to 63% in NOx emissions.
Article
Green & Sustainable Science & Technology
Michael Barbour, Devin Udesen, Sam Bentson, Anamol Pundle, Casey Tackman, David Evitt, Paul Means, Peter Scott, Dean Still, John Kramlich, Jonathan D. Posner, Daniel Lieberman
Summary: Nearly 40% of the world's population relies on biomass stoves for indoor cooking, which can lead to harmful emissions. Proper air injection technology has been found to significantly reduce emissions and improve combustion efficiency. Forced air injection shows potential for both emission reductions and increased burn rate in biomass stoves.
ENERGY FOR SUSTAINABLE DEVELOPMENT
(2021)
Article
Thermodynamics
Halina Pawlak-Kruczek, Jakub Mularski, Michal Ostrycharczyk, Michal Czerep, Marcin Baranowski, Tadeusz Maczka, Krzysztof Sadowski, Patryk Hulisz
Summary: This study investigates the combustion of pulverized coal with unburned char recovered from the ash of an industrial boiler. Two plasma burners are installed to improve the combustion efficiency and reduce the amount of unburned fuel. CFD modeling and laboratory tests are used to analyze the combustion behavior, and the results show that the use of plasma burners improves the mixing and temperature distribution, resulting in higher temperatures at the combustion chamber outlet.
Article
Thermodynamics
Ryno Laubscher, Schalk van der Merwe
Summary: This study introduces a computational fluid dynamics model of a semi-suspension fired bagasse boiler, which accurately predicts steam and gas temperatures with relative errors of less than 2%. The model is able to simulate heat transfer processes and investigate heat flux distributions in heat exchangers, providing valuable insights into boiler performance.
THERMAL SCIENCE AND ENGINEERING PROGRESS
(2021)
Article
Thermodynamics
Jingyuan Zhang, Tian Li, Henrik Strom, Terese Lovas
Summary: In the study, a transient 3D model utilizing a new coupling approach for fixed bed biomass combustion is presented. The model, formulated as an Eulerian-Lagrangian framework with optimized sub-models, is validated through laboratory-scale experiments and sensitivity analysis, showing good agreement with experimental measurements and discussing the coupling effects.
COMBUSTION AND FLAME
(2022)
Article
Thermodynamics
Rafal Kobylecki, Robert Zarzycki, Zbigniew Bis, Marcin Panowski, Mateusz Winski
Summary: By optimizing fuel spreading and secondary air distribution, significant improvement of boiler performance and reduction of fouling rate can be achieved.
Article
Environmental Sciences
Yarima Torreiro Villarino, Leticia Perez Rial, Angela Rodriguez-Abalde
Summary: The study demonstrates the feasibility of using residual biomass as an energy source for micro-cogeneration, and validates the efficiency of obtaining electricity and heat at low temperatures through micro-cogeneration tests.
JOURNAL OF ENVIRONMENTAL MANAGEMENT
(2022)
Article
Thermodynamics
J. P. Paredes-Sanchez, J. L. Miguez, D. Blanco, M. A. Rodriguez, J. Collazo
Article
Energy & Fuels
Miguel A. Gomez, Sergio Chapela, Joaquin Collazo, Jose L. Miguez
Article
Engineering, Multidisciplinary
Roberto Bellas, Arturo Gonzalez-Gil, Miguel A. Gomez, Jacobo Porteiro, Jose L. Miguez
Review
Energy & Fuels
Jose Luis Miguez, Jacobo Porteiro, Raquel Perez-Orozco, David Patino, Miguel Angel Gomez
Article
Chemistry, Applied
Cesar A. Bermudez, Jacobo Porteiro, Luis G. Varela, Sergio Chapela, David Patino
FUEL PROCESSING TECHNOLOGY
(2020)
Article
Green & Sustainable Science & Technology
Raquel Perez-Orozco, David Patino, Jacobo Porteiro, Jose Luis Miguez
Article
Energy & Fuels
Sergio Chapela, Jacobo Porteiro, Jose Luis Miguez, Frank Behrendt
Review
Green & Sustainable Science & Technology
Jose Luis Miguez, Jacobo Porteiro, Frank Behrendt, Diana Blanco, David Patino, Alba Dieguez-Alonso
Summary: This review evaluates the impact of additives on the combustion behavior of biomass with high ash-forming species, focusing on emissions and deposits formation. Due to the high variability in biomass composition, using additives to reduce emissions and deposits is crucial for different biomass types and combustion conditions.
RENEWABLE & SUSTAINABLE ENERGY REVIEWS
(2021)
Article
Engineering, Mechanical
Ruben Carranza Fernandez, Thomas Tobie, Joaquin Collazo
Summary: Increasing gearbox power density is crucial for reducing the cost of wind energy. The load carrying capacity of gears is strongly influenced by surface conditions. Additional finishing methods such as shot peening and superfinishing can significantly enhance gear load capacity, yet these effects have not been adequately addressed in current standards.
INTERNATIONAL JOURNAL OF FATIGUE
(2022)
Article
Agricultural Engineering
Natalia Cid, David Patino, Raquel Perez-Orozco, Jacobo Porteiro
Summary: Biomass combustion emits hazardous particulate matter (PM) that poses risks to human health. Electrostatic precipitators (ESPs) are considered an effective mitigation technology, but there is a lack of comprehensive analysis and solution consolidation. This study tested an easily attachable ESP design and analyzed its performance in capturing PM emissions from a pellet boiler. The results showed that increasing voltage improved separation efficiency, and a thinner discharge electrode achieved better efficiency and stable operation.
BIOMASS & BIOENERGY
(2022)
Article
Computer Science, Artificial Intelligence
A. Larranaga, S. L. Brunton, J. Martinez, S. Chapela, J. Porteiro
Summary: Machine learning has been widely adopted in engineering, and this paper develops a model capable of predicting the performance of enhanced microsurface geometries for cooling electronic and power systems. The design of such geometries usually requires expensive simulations, so a simplified subset of basic shapes is used. To explore more diverse geometries, an algorithm is developed based on a comprehensive database, enabling estimation of various quantities of interest with relative errors below 10% and 2%. This demonstrates the utility of machine learning in rapidly predicting the performance of novel enhanced microsurfaces.
MACHINE LEARNING-SCIENCE AND TECHNOLOGY
(2023)
Article
Energy & Fuels
Juan Jesus Rico, Raquel Perez-Orozco, Jacobo Porteiro, David Patino
Summary: This study investigates the effects of adding a zirconium porous medium on emissions from a laboratory-scale biomass combustor, focusing on particulate matter and volatile organic compounds. A unique sampling train using active carbon adsorption was designed to capture volatiles, and thermogravimetric analysis showed the porous medium's affinity for lighter organic compounds. The retention time of the sample was also examined, revealing significant degradation after three to six hours of storage. Analysis of particulate matter emissions demonstrated a correlation with volatile organic compounds, with lower solid particle emissions resulting in minimized volatile release.
Article
Engineering, Mechanical
Ruben Carranza Fernandez, Thomas Tobie, Sascha Rommel, Joaquin Collazo
Summary: Gearbox power density is crucial for wind energy competitiveness. As wind turbines increase in size to lower the cost of energy, the role of bending fatigue in gearbox design becomes more significant. While shot peening is commonly used to enhance bending capacity, other techniques like root grinding and superfinishing have not been fully explored. This study investigates the tooth root bending strength of carburized gears under different root finishing conditions and finds that superfinishing has no significant impact after shot peening. On the other hand, root grinding prior to shot peening shows potential for increased bending capacity, but the possibility of high cycle subsurface failures must be considered.
INTERNATIONAL JOURNAL OF FATIGUE
(2023)
Article
Engineering, Electrical & Electronic
Natalia Cid, David Patino, Jacobo Porteiro, David Eiroa
Summary: The combustion of fuels results in the emission of particulate matter and the occurrence of fouling and slagging phenomena. It is important to identify the shape of particle layers to develop solutions for cleaning or preventing deposition on affected areas. A measurement procedure has been proposed to determine the thickness and profile of particle/ash layers deposited on surfaces.
IEEE TRANSACTIONS ON INSTRUMENTATION AND MEASUREMENT
(2021)
Article
Energy & Fuels
Raquel Perez-Orozco, David Patino, Jacobo Porteiro, Juan Jesus Rico
