Article
Thermodynamics
Robin Streier, Ines Veckenstedt, Thomas Deck, Karl Lampe, Viktor Scherer
Summary: Superstoichiometric oxygen combustion, also known as pure-oxy-fuel, is a novel concept that can reduce CO2 emissions in cement clinker production. In this study, we simulate the influence of superstoichiometric combustion combined with different refuse-derived fuel (RDF) compositions and particle sizes on process parameters and cement clinker quality in a rotary kiln. The results show that similar clinker qualities can be achieved compared to a standard air-fired kiln.
COMBUSTION SCIENCE AND TECHNOLOGY
(2023)
Article
Thermodynamics
Mengmeng Zhou, Shuai Wang, Kun Luo, Jianren Fan
Summary: In this study, the co-firing of biomass and coal in an oxy-fuel bubbling fluidized bed combustor was investigated using numerical simulations. The results revealed the effects of solid fuel injection and gas flow on gas-solid fluxes and gas product distributions.
Article
Thermodynamics
Yuyang Chen, Shiliang Yang, Jianhang Hu, Hua Wang
Summary: In this study, the hydrodynamics and thermochemical characteristics of dense reactive flow in a 0.1 MWth pilot-scale CFB were simulated. The impacts of key operating parameters on gas thermal properties, gas species distribution and gas-solid flux were studied. The results showed non-uniform distributions of gas-solid flow dynamics and thermochemical variables in the riser, with combustible gases mainly concentrating in the left area.
Article
Green & Sustainable Science & Technology
Hetian Chi, Miguel A. Pans, Chenggong Sun, Hao Liu
Summary: In this study, the use of molochite and dolomite as bed additives in a fluidised bed combustor was investigated to counter agglomeration during the combustion of wheat straw and miscanthus pellets. The results showed that dolomite was superior to molochite in prolonging defluidisation time when firing wheat straw. Lime addition to fuel had the most significant improvement on combustion performance for both fuels. The oxy-fuel combustion atmosphere had a great impact on the effectiveness of dolomite but little influence on the effectiveness of molochite.
Article
Thermodynamics
Runjuan Kong, Wei Li, Haigang Wang, Qiangqiang Ren
Summary: This research investigates the energy efficiency of a pressurized oxy-fuel combustion system through simulations and optimizations. The pressurized circulating fluidized bed (CFB) oxy-fuel combustion technology is found to improve the net electric generation efficiency, and various parameters are optimized to further enhance the system's net efficiency.
Article
Thermodynamics
Ali Cemal Benim, Cansu Deniz Canal, Yakup Erhan Boke
Summary: Computational investigation of swirling pulverized coal and biomass flames for oxy-combustion reveals that the Reynolds Stress Model (RSM) captures unsteady dynamics better than the k-epsilon model. Predicted velocities show better agreement with measurements using RSM. However, both models underestimate the measurements, with discrepancies quantified in peak values of axial velocity. Biomass flame is predicted to be nearly twice as long as coal flame.
Article
Thermodynamics
Hendrik Nicolai, Paulo Debiagi, Xu Wen, Louis Dressler, Anna Massmeyer, Johannes Janicka, Christian Hasse
Summary: This work introduces a new approach based on Large-Eddy Simulation (LES) coupled with a flamelet description of the gas-phase and seamless detailed solid-fuel kinetics, and applies it to a self-sustained oxy-fuel coal combustion chamber. The approach enables a detailed description of the turbulent flow field, mixing, and heat transfer, including thermal radiation and the radiative transport equation. The flamelet description of the gas phase allows for accurate and computationally efficient representation of turbulence-chemistry interactions. Coupled with a solid-fuel kinetic mechanism, it allows for seamless simulation of the particle conversion process.
COMBUSTION AND FLAME
(2022)
Article
Energy & Fuels
C. Pieper, S. Wirtz, S. Schaefer, V. Scherer
Summary: This study investigates the impact of coatings on the cement clinker production process within a rotary kiln through CFD simulations. Results show that a thin coating profile can increase gas phase temperatures and reduce free lime content of the final product, while a heavy coating may lower local gas phase temperatures and result in a slight increase in free lime content in the clinker.
Article
Energy & Fuels
Shiquan Shan, Xichuan Cai, Kun Li, Qi Zhang, Zhijun Zhou, Yanwei Zhang
Summary: This paper studies the radiative energy characteristics of oxy-fuel combustion of pulverized coal, focusing on spectral distribution characteristics. Experimental results show that the intensity of radiative energy and exergy increase with oxygen ratio and combustion temperature, while different atmospheres have little effect on radiation characteristics. One-dimensional calculation can better reveal proportional characteristics of spectral radiation.
Article
Energy & Fuels
Hendrik Nicolai, Paulo Debiagi, Johannes Janicka, Christian Hasse
Summary: Oxy-fuel combustion combined with carbon capture technologies has the potential to rapidly reduce CO2 emissions in coal-fired power plants. However, the combustion of solid fuels in an oxygen-carbon dioxide environment is not fully understood. This study aims to analyze the impact of oxygen content on thermo-chemical conversion by applying a recently developed approach to a range of oxy-fuel swirl flames.
Article
Thermodynamics
Juraj Raic, Christian Gaber, Philipp Wachter, Martin Demuth, Hannes Gerhardter, Mario Knoll, Rene Prieler, Christoph Hochenauer
Summary: Glass furnaces pose a continuous challenge for CFD simulations due to the complex description of multiple phases. Research identified unsuitable oxy-fuel combustion models and a lack of advanced coupling methods. A 3D CFD simulation model for an oxy-fuel glass furnace with electric boosting introduced significant improvements, resulting in accurate temperature predictions of less than 1.93% and 3.81% of experimental data for the combustion chamber and glass tank, respectively.
APPLIED THERMAL ENGINEERING
(2021)
Article
Energy & Fuels
H. Nicolai, X. Wen, F. C. Miranda, D. Zabrodiec, A. Massmeyer, F. di Mare, A. Dreizler, C. Hasse, R. Kneer, J. Janicka
Summary: This paper investigates a self-sustained swirl-stabilized pulverized coal combustion chamber and validates numerical models under different atmospheres. The simulations show good agreement with measurement data, demonstrating the suitability of the model for predicting coal combustion in both air and oxy-fuel atmospheres.
Article
Thermodynamics
Haoran Sun, Guirong Bao, Shiliang Yang, Jianhang Hu, Hua Wang
Summary: The research investigated the effects of ring-type internals on the particle-scale characteristics in the riser of the circulating fluidized bed using the multiphase particle-in-cell method. The results showed that the incorporation of internals significantly influenced the distribution and motion of gas and particles, and increasing the internal number or reducing the aperture ratio improved the sand temperature in the riser.
ENERGY CONVERSION AND MANAGEMENT
(2023)
Article
Engineering, Chemical
Guoqing Lian, Wenqi Zhong
Summary: The CFD-DEM coupled with heat transfer and chemical reaction sub-models was used to simulate oxy-char combustion in a fluidized bed. The study investigated the thermal conversion characteristics of char, including reaction rate, combustion temperature, and heat transfer. Results showed that convection heat and radiation heat were the main contributors, while conduction heat played an insignificant role.
Review
Energy & Fuels
Chen Ge, Shiyuan Li, Linwei Wang
Summary: Oxy-fuel circulating fluidized bed combustion (Oxy-CFBC) is a promising and sustainable technology for carbon capture, utilization, and sequestration in coal-fired power plants. In the past 15 years, research on Oxy-CFBC has rapidly developed, from lab-scale to industrial-scale facilities. This paper reviews the research status of Oxy-CFBC, including models, heat transfer, combustion characteristics, pollutant formation and emission, and system optimization. It also analyzes different fuels and the differences in NOx emission and desulfurization mechanism between air combustion and oxy-combustion modes. The review highlights the importance of gas staging and oxygen staging in reducing NO emissions, and discusses new generation technologies and challenges for future research and industrial application of Oxy-CFBC.
Article
Construction & Building Technology
Bodil Hokfors, Dan Bostrom, Erik Viggh, Rainer Backman
ADVANCES IN CEMENT RESEARCH
(2015)
Article
Engineering, Chemical
Matias Eriksson
INTERNATIONAL JOURNAL OF MINERAL PROCESSING
(2016)
Article
Construction & Building Technology
Bodil Hokfors, Matias Eriksson, Erik Viggh
ADVANCES IN CEMENT RESEARCH
(2014)
Article
Energy & Fuels
Matias Eriksson, Markus Carlborg, Markus Brostrom
Article
Construction & Building Technology
Erik Viggh, Matias Eriksson, Bodil Wilhelmsson, Rainer Backman
Summary: Analytical methods were studied for characterizing cement raw meal during heating in different atmospheres. It was found that replacing limestone with 10% slag affected the formation of incipient belite and clinker liquid precursors in the temperature range of 600-1050 degrees C. The results showed that the presence of slag favored the reduction of quartz and C2S in comparison to sand in the samples, suggesting that silicon dioxide in slag did not react in this temperature range.
ADVANCES IN CEMENT RESEARCH
(2021)
Article
Energy & Fuels
Karin Sandstrom, Markus Brostrom, Matias Eriksson
Summary: This study delves into the interaction between coal ash and limestone during calcination, revealing that the interface between ash and quicklime affects the microstructure of quicklime and reduces the amount of reactive CaO. The laboratory methodology proves to be useful in enhancing the understanding of ash-quicklime interactions.
Article
Energy & Fuels
Karin Sandstrom, Matias Eriksson, Markus Brostrom
Summary: Net CO2 emissions from quicklime production can be reduced by using renewable solid fuels or sustainably produced electricity. A study on the effects of new heat sources shows that olive pomace ash has a more severe impact on the microstructure of quicklime compared to a mixture of conventional coal and solid biofuel. The presence of potassium in olive pomace ash leads to significant coarsening of the quicklime microstructure, potentially decreasing available CaO and reactivity. The findings highlight the importance of considering heat source options in industrial quicklime production.
Article
Geochemistry & Geophysics
Katarzyna Cwik, Markus Brostrom, Krister Backlund, Kenneth Fjader, Emil Hiljanen, Matias Eriksson
Summary: This paper presents an industrial case study on the thermal decrepitation of limestone in quicklime production. The study analyzes the correlation between chemical composition and thermal decrepitation, as well as the differences in decrepitation behaviors of limestone samples with similar chemical compositions. The results show that there is no strong correlation between chemical composition and thermal decrepitation. Additionally, the study reveals that the presence of a fracture network in the limestone can stabilize it and reduce thermal decrepitation.
Article
Materials Science, Ceramics
Naresh Kumar Wagri, Markus Carlborg, Matias Eriksson, Charlie Ma, Markus Brostro, Britt M. Andersson
Summary: This study investigates the use of MgO-based refractories in lime kilns, which can withstand high temperatures and chemical environments. The growing interest in reducing CO2 emissions has led to the exploration of bio-based fuels as alternatives to fossil fuels. The potential for refractory corrosion from potassium-rich biomass ash was examined by studying the infiltration of olive pomace ash into magnesia/spinel refractories. It was found that molten ash infiltrated the refractories, causing an attack on the spinel components by potassium.
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
(2023)
Article
Construction & Building Technology
Jose Aguirre Castillo, Markus Brostroem, Matias Eriksson
Summary: The use of high-temperature X-ray diffraction (HT-XRD) was assessed for studying the mass transfer and burnability of raw meal constituents in forming clinker phases and determining the amount of free lime (calcium oxide). The results showed that HT-XRD produced good results for evaluating burnability and provided insight into early reactions in a cement kiln. The size of quartz particles was found to affect crystal expansion and the formation of silica polymorphs, leading to variations in the formation of C2S. However, the influence of β-quartz on the reduction of free lime still lacks sufficient knowledge.
ADVANCES IN CEMENT RESEARCH
(2023)
Article
Energy & Fuels
Naresh Kumar Wagri, Markus Carlborg, Matias Eriksson, Charlie Ma, Markus Brostrom, Britt M. Andersson
Summary: This study examined the interaction between coal ash and three commercially available MgO-based refractory materials. The results showed that molten silicates infiltrated the refractories and diffused to a depth of 2.8mm through grain boundaries and pores. The study also revealed the formation of Mg2SiO4 corrosion product and the dissolution or dislocation of refractory components.
Article
Engineering, Multidisciplinary
Matias Eriksson, Bodil Hokfors, Rainer Backman
JOURNAL OF ENGINEERING TECHNOLOGY
(2015)