Article
Energy & Fuels
Ramin Khodabandehlou, Dominik Kirschenmann, Ronny Schimpke, Andreas Richter, Massoud Massoudi Farid, Hamid Reza Norouzi, Stefan Guhl, Afsanehsadat Larimi, Navid Mostoufi
Summary: This study investigates ash agglomeration as a potential problem in fluidized bed gasifiers. The results show that the defluidization temperature for ash agglomeration increases with the gas velocity, but remains constant after a certain fluidization number.
Article
Engineering, Chemical
Fangfang Wu, Yeju Han, Kunsen Lin, Chiou-Liang Lin, Jia-Hong Kuo
Summary: In the incineration process, agglomeration occurs due to the combustion of wastes with adhesion materials like alkalis and earth alkalis. Understanding the properties of sand bed materials is important for the defluidization process. This study analyzed the composition of sand and found that defluidization time decreases with increasing particle size. A model using Support Vector Regression was effective in predicting defluidization time.
Article
Engineering, Environmental
Xu Zhang, Jun Li, Zheng Zou, Huigang Zhang, Dong Yan, Zhan Du, Zhaohui Xie, Qingshan Zhu
Summary: We propose a novel force balance model to predict the defluidization phenomena of ilmenite particles in a fluidized bed reactor. The model is based on the cohesion forces of iron nuclei on the particle surface, which increase with the extent of reduction and eventually trigger defluidization. The predicted surface coverage of particles agrees well with experimental results.
CHEMICAL ENGINEERING JOURNAL
(2023)
Article
Energy & Fuels
Elmeri Pienihakkinen, Christian Lindfors, Taina Ohra-aho, Juha Lehtonen, Tom Granstrom, Minna Yamamoto, Anja Oasmaa
Summary: This study investigated fast pyrolysis of hydrolysis lignin in fluidized bed units, identifying technical challenges related to lignin degradation rates, secondary reactions in the vapor phase, pressure buildup, and deposit formation. The carbohydrate content of hydrolysis lignin was found to impact processability, with lower carbohydrate content leading to more challenges such as clogging and bed agglomeration. Solutions such as adding a rotating mixer or feeding raw material in different sections of the reactor were proposed to overcome these challenges.
Article
Pharmacology & Pharmacy
Hao Fu, Kaixuan Teng, Jie Zhao, Sheng Zhang, Haibin Qu
Summary: A novel approach using diffuse reflectance near-infrared spectroscopy was developed to detect bed fluidity in gas-solid fluidized beds. Two indicators, bubble proportion and skewness, were investigated to characterize bed fluidity. The results show that both indicators are sensitive to changes in bed fluidity and can be used for monitoring and early warning of bed fluidization in a granulation process.
Article
Energy & Fuels
T. McCann, E. J. Marek, Yaoyao Zheng, J. F. Davidson
Summary: This study investigates the combustion of waste glycerol in a fluidised bed. The results show that continuous burning of industrial glycerol is possible, but agglomeration of bed material should be taken into consideration. Moreover, glycerol can be autonomously burned in a fluidised bed without supplying heat.
Article
Engineering, Chemical
Frederik Zafiryadis, Anker Degn Jensen, Weigang Lin, Elisabeth Akoh Hove, Morten Boberg Larsen, Hao Wu
Summary: This study utilizes the Eulerian-Lagrangian multiphase particle-in-cell method to simulate the injection of a gas-liquid spray into a gas-solid fluidized bed. The model accurately predicts the gas temperature distribution within the injection region, but discrepancies may arise due to the presence of wet particle agglomerates in the spray region.
CHEMICAL ENGINEERING SCIENCE
(2022)
Article
Biochemistry & Molecular Biology
Gary Reineccius, Shardul Patil, Vaidhyanathan Anantharamkrishnan
Summary: This research compares granulation to spray drying/agglomeration for producing flavoring particles. The study finds that granulation produces better properties, such as improved oxidation resistance, higher density, without the need for a two-step process.
Article
Engineering, Chemical
Yoshiro Adachi, Masayuki Horio
Summary: The study found that using coarse spherical alumina particles as the bed material in a fluidized bed can effectively prevent defluidization during the calcination process and somewhat impact the magnetic properties. Adjusting the Fe/Sr ratio in RM was effective in eliminating unreacted Fe2O3 residues.
CANADIAN JOURNAL OF CHEMICAL ENGINEERING
(2021)
Article
Thermodynamics
Saurabh Gupta, Santanu De
Summary: This study investigates the gasification of low-grade, sub-bituminous coal in a pilot-scale bubbling fluidized bed reactor. The effects of equivalence ratio and steam/coal ratio on the composition of the syngas, carbon conversion, cold gas efficiency, and agglomeration behavior are studied.
Article
Engineering, Chemical
Eric Otto, Robert Duerr, Gerd Strenzke, Stefan Palis, Andreas Bueck, Evangelos Tsotsas, Achim Kienle
Summary: Fluidized bed spray agglomeration is a significant industrial particle formation process, and mathematical process modeling plays a crucial role in analyzing mechanistic processes, intensification, and control. This study focuses on the influence of seven operational parameters on particle size distribution and introduces a general method for obtaining a quantitative formulation of the dependency between agglomeration rate and process conditions.
ADVANCED POWDER TECHNOLOGY
(2021)
Article
Energy & Fuels
T. Leffler, M. Eriksson, B. Leckner, F. Lind, F. Winquist, P. Knutsson
Summary: The thermal conversion of biomass fuel mixes in fluidized beds can cause agglomeration. To counteract agglomeration, bed material is gradually exchanged with virgin bed material, and this results in increased disposal of used bed material. Furthermore, the bed material exchange represents a costly option, as it involves a cost for virgin bed material, for landfill, and for unplanned downtime of the plant. This paper presents a novel method for the evaluation of bed material quality: the electronic tongue (ET). Evaluation of bed material quality can contribute toward decreasing the cost of unnecessary exchanges of bed material. The proposed method was tested on bed material sampled on an almost daily basis from a commercial fluidized bed boiler during several months of operation. A two-electrode ET was used for the evaluation of the bed material quality. The analysis relied on pulsed voltammetry measurements and multivariate data analysis with Principal Component Analysis (PCA). The results suggest that it is possible to follow bed material changes and that the ET, after further development, may be used to optimize the material flows connected to the bed material. Further research is being conducted to optimize the ET's performance and its application in monitoring bed material.
Article
Biochemistry & Molecular Biology
D. Lee, B. Yoo
Summary: This study investigated the effects of adding maltodextrin during agglomeration on the physical, rheological, and structural properties of different types of water-soluble cellulose gums. The results showed that different cellulose gums exhibited varying flowability and cohesiveness in the presence of MD, and the concentration of MD influenced their porosity and dynamic moduli.
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
(2021)
Article
Chemistry, Applied
Victor Purnomo, Duygu Yilmaz, Henrik Leion, Tobias Mattisson
Summary: This study investigated the defluidization phenomena of oxygen carriers under highly reducing conditions, finding that iron-based oxygen carriers were more prone to defluidization while manganese-based materials were less affected.
FUEL PROCESSING TECHNOLOGY
(2021)
Review
Engineering, Chemical
Raul Favaro Nascimento, Mariana Ferreira Avila, Osvaldir Pereira Taranto, Louise Emy Kurozawa
Summary: This study conducted a bibliometric analysis to examine the global panorama and trends in agglomeration in a fluidized bed over the past four decades. China, Sweden, Germany, Canada, and the United States were identified as the most productive countries in terms of publications. Keyword analysis revealed the importance of fluidization, biomass, granulation, defluidization, and coating in agglomeration in fluidized beds. The study also found that the main focuses of publications were granulation and combustion, and research emphasis is progressing towards evaluating operating parameters and measurement techniques to enhance theoretical approaches in agglomeration in fluidized beds.
Article
Chemistry, Applied
Tenna Frydenberg, Claus Erik Weinell, Kim Dam-Johansen, Eva Wallstrom, Soren Kiil
Summary: In order to reduce the usage of copper compounds in coatings, researchers have explored the use of silica aerogel-encapsulated copper pyrithione (CuPT). Experimental results show that this method does not compromise the mechanical properties and antifouling performance of the coatings. The CuPT loading of the silica aerogels does not significantly affect the water absorption and rheology of the coatings, but it does reduce the hardness of the coatings. Moreover, the coatings containing silica aerogel-encapsulated CuPT exhibit higher antifouling resistance compared to coatings without encapsulated CuPT.
JOURNAL OF COATINGS TECHNOLOGY AND RESEARCH
(2023)
Article
Engineering, Chemical
Mohamadali Mirzaei, Peter Arendt Jensen, Mohammadhadi Nakhaei, Hao Wu, Sam Zakrzewski, Haosheng Zhou, Weigang Lin
Summary: The Dense Discrete Phase Model coupled with an agglomeration model is developed and validated for the simulation of industrial cyclones with high solid loads. The performance of the model is influenced by sub-models, model parameters, and numerical parameters. A sensitivity analysis was conducted to optimize the model's performance, identifying the turbulence model and particle-particle restitution coefficient as having the strongest influence. The study recommends a set of sub-models, model parameters, and numerical parameters for accurately predicting the hydrodynamics of large-scale highly loaded cyclones.
Article
Thermodynamics
Hao Luo, Xinyan Liu, Lukasz Niedzwiecki, Xiaoqin Wu, Weigang Lin, Bona Lu, Wei Wang, Hao Wu
Summary: This study analysed the effects of model dimensionality, particle shrinkage, and boundary layer reactions on particle-scale modelling of biomass char conversion under pulverized fuel combustion conditions using six models. The 1D_SPM_BH model with consideration of intra-particle heat and mass transfer, particle shrinkage, and boundary layer reactions was found to be the most appropriate model for biomass char conversion. The 0D_Cons model provided a good approximation for small particle size at specific temperatures, while the 0D_SPM model overestimated the char conversion rate. Considering intra-particle heat and mass transfer improved the model prediction of char conversion time and reaction contributions, and boundary layer reactions had a significant effect on char conversion prediction for large particles and high temperatures.
PROCEEDINGS OF THE COMBUSTION INSTITUTE
(2023)
Article
Engineering, Environmental
Mohamadali Mirzaei, Sonnik Clausen, Hao Wu, Sam Zakrzewski, Mohammadhadi Nakhaei, Haosheng Zhou, Kasper Martin Jonck, Peter Arendt Jensen, Weigang Lin
Summary: A hybrid multiphase model (Dense Discrete Phase Model, DDPM) coupled with a k-omega sst turbulence model, which includes gas-solid heat exchange, was developed to simulate industrial-scale cyclone preheaters with high solid loadings. The model was validated by experimental measurements, including pressure drop, gas and particle exit temperature, local gas velocity profiles (measured using LDA), and gas temperature profiles (measured using thermocouple and FTIR). The model showed reasonable agreement with the experimental data and accurately captured major trends caused by changes in operating parameters.
CHEMICAL ENGINEERING JOURNAL
(2023)
Article
Energy & Fuels
Emil O. Lidman Olsson, Daniel Schmid, Oskar Karlstrom, Kasper Enemark-Rasmussen, Henrik Leion, Songgeng Li, Peter Glarborg, Kim Dam-Johansen, Hao Wu
Summary: Biomass can be converted into heat, power, and biofuels through thermal conversion processes, but the presence of phosphorus in certain types of biomass can lead to operational or environmental issues when released. The mechanisms behind phosphorus release and high-temperature phosphorus chemistry need to be understood in order to efficiently recover phosphorus from biomass residues. This study investigated the release of phosphorus from wheat bran char and sunflower seed char under various gas environments and temperatures.
Article
Engineering, Chemical
Haiwei He, Chuigang Fan, Songgeng Li, Weigang Lin
Summary: This study proposes a reductive decomposition method for phosphogypsum to produce CaO under a CO2 atmosphere, aiming to avoid the presence of CaS in the product. Thermogravimetric tests combined with thermodynamic analysis reveal three reaction stages: CaSO4 reduction, reaction between CaS and CaSO4, and CaS oxidation by CO2. The reaction path is influenced by the C/CaSO4 molar ratio and temperature. Experiments conducted in a fluidized bed reactor show that over 96.2% of CaSO4 in phosphogypsum can be decomposed into CaO at 1000°C and a C/CaSO4 molar ratio of 1.0 within 83.7 minutes. Phosphogypsum decomposition in air or nitrogen leads to lower CaO production. Additionally, kinetic analyses of CaS oxidation with CO2 in the presence of CaSO4 are performed to understand the effect of the CaS-CaSO4 reaction on the CaS-CO2 reaction.
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
(2023)
Review
Engineering, Chemical
Frederik Zafiryadis, Anker Degn Jensen, Weigang Lin, Elisabeth Akoh Hove, Morten Boberg Larsen, Hao Wu
Summary: This paper provides a thorough and up-to-date review of experimental and numerical investigations of gas-liquid sprays into gas-solid fluidized beds. It presents a phenomenological description of the prevalent mechanisms of gas-liquid injection under different operating conditions and identifies suitable computational fluid dynamic models for simulating the mechanisms involved in gas-liquid-solid interactions, along with recommendations for future work.
Article
Engineering, Chemical
Mohamadali Mirzaei, Sonnik Clausen, Hao Wu, Mohammadhadi Nakhaei, Haosheng Zhou, Kasper Jonck, Peter Arendt Jensen, Weigang Lin
Summary: The Dense Discrete Phase Model (DDPM) was used with Oka's erosion model to investigate erosion caused by solid particle impacts in an industrial cyclone preheater. The model's predictions of flow pattern and temperature profile were validated with measurements in an industrial cyclone preheater, as well as against results from a lab-scale cyclone in the literature. The model also successfully predicted the erosion patterns observed in the industrial cyclone preheater, and parametric studies showed that gas flow rate and inlet temperature had the greatest impact on erosion.
Article
Chemistry, Applied
Ziyou Li, Huichao Bi, Claus Erik Weinell, Giulia Ravenni, Lidia Benedini, Kim Dam-Johansen
Summary: Pyrolyzed and gasified biochar nanoparticles (BCN) were incorporated into zinc epoxy coatings to enhance their barrier protection and zinc utilization rate. The BCN-modified formulations showed improved anticorrosive performance, especially on formulations with lower zinc content. The enhanced performance was attributed to the filling of micropores and extra electrical connections provided by BCN. This study provides a sustainable solution for enhancing the anticorrosive performance of zinc epoxy coatings.
PROGRESS IN ORGANIC COATINGS
(2023)
Review
Multidisciplinary Sciences
Isabel Pol Segura, Navid Ranjbar, Anne Juul Damo, Lars Skaarup Jensen, Mariana Canut, Peter Arendt Jensen
Summary: There is a growing interest in alternative cements to reduce the environmental impact of cement production. One promising option is alkali-activated materials, which have similar performance to traditional cement and can significantly reduce CO2 emissions. This paper reviews relevant technologies for alkali-activated cement production and discusses considerations for mixing and casting concrete. It also provides an overview of the market, including commercialized products, CO2 emissions, costs, and future considerations. Alkali-activated materials can reduce CO2 emissions by over 68% compared to Portland cement but are estimated to be 2 to 3 times more expensive.
Article
Chemistry, Multidisciplinary
Giovanni Aprile, Ajinkya V. Pandit, Jody Albertazzi, Ayse Eren, Gerard Capellades, Alpana A. Thorat, Janaka C. Gamekkanda, Thomas Vetter, Tommy Skovby, Gurkan Sin, Hao Wu, Kim Dam-Johansen, Allan S. Myerson
Summary: Continuous crystallization is crucial in the pharmaceutical industry's transition to continuous manufacturing, but developing a process using data from continuous operation is material-intensive and requires multiple experiments. A novel tubular crystallizer configuration presented in this study reduces material requirements and reactor footprint, allowing effective mimicking of long residence times with plug flow conditions.
CRYSTAL GROWTH & DESIGN
(2023)
Article
Polymer Science
Shu Li, Huichao Bi, Claus Erik Weinell, Kim Dam-Johansen
Summary: This study investigated the water uptake behavior of a commercial epoxy coating on steel panels and free films through non-destructive techniques. The results revealed the absorption and leaching processes of water in the coating film and provided insights into the water uptake mechanisms.
JOURNAL OF APPLIED POLYMER SCIENCE
(2023)
Article
Chemistry, Applied
Shujie Lin, Huichao Bi, Claus Erik Weinell, Seyednezamaddin Azizaddini, Kim Dam-Johansen
Summary: Underwater cleaning is becoming increasingly important in biofouling prevention. This study introduces a laboratory scale self-designed automated underwater cleaning system (AUCS) that can achieve force monitoring during the cleaning process. The effects of brush type and cleaning frequency were investigated on different coatings, showing varying fouling resistance and cleaning efficiency. The results from field testing also revealed the superior performance of certain brush types in terms of fouling resistance and cleaning efficiency.
PROGRESS IN ORGANIC COATINGS
(2023)
Article
Chemistry, Applied
Mads Juhl, Michael Z. Hauschild, Kim Dam-Johansen
Summary: When developing sustainable products in the coatings industry, conducting Life Cycle Assessments (LCA) provides guidance for choosing a sustainable path. This study focuses on the sustainability performance of protective coatings, using the coating of an offshore wind turbine tower as a case study. The assessment reveals that the majority of environmental impacts, including climate change, stem from the manufacturing of the steel. Therefore, prioritizing a durable coating system that protects the steel and prolongs its lifetime, reducing the need for repairs, is crucial for sustainability. The development path includes substituting toxic substances, using zinc-rich epoxy or zinc silicate coatings instead of thermal sprayed metal, replacing organic solvents with water, reducing steel usage, substituting organic binders with alternatives with lower carbon footprints, and facilitating the recycling of structural materials for reuse.
PROGRESS IN ORGANIC COATINGS
(2024)
Correction
Chemistry, Applied
Jia Liu, Juntong Dong, Xiaodan Li, Teng Xu, Zhenguo Li, Jeffrey Dankwa Ampah, Mubasher Ikram, Shihai Zhang, Chao Jin, Zhenlong Geng, Tianyun Sun, Haifeng Liu
FUEL PROCESSING TECHNOLOGY
(2024)
Article
Chemistry, Applied
Seba Alareeqi, Daniel Bahamon, Kyriaki Polychronopoulou, Lourdes F. Vega
Summary: This study explores the potential application of single-atom-alloy (SAA) catalysts in bio-oils hydrodeoxygenation refining using density functional theory (DFT) and microkinetic modeling. It establishes the relationships between stability, adsorptive properties, and activity structures for bio-oil derivatives, providing guidance for the synthesis of cost-effective SAA combinations.
FUEL PROCESSING TECHNOLOGY
(2024)
Article
Chemistry, Applied
Bin Hu, Wen -Ming Zhang, Xue-Wen Guo, Ji Liu, Xiao Yang, Qiang Lu
Summary: This study explored the pyrolysis behaviors and mechanisms of different monosaccharides, including arabinose, galactose, galacturonic acid, and glucuronic acid. The roles of structural differences in these monosaccharides were analyzed, and it was found that glucuronic acid undergoes a special C-C bond breaking reaction during pyrolysis. The findings provide a deep understanding of the pyrolysis chemistry of hemicellulose and the role of different branches.
FUEL PROCESSING TECHNOLOGY
(2024)
Review
Chemistry, Applied
Youwei Zhi, Donghai Xu, Guanyu Jiang, Wanpeng Yang, Zhilin Chen, Peigao Duan, Jie Zhang
Summary: Hydrothermal carbonization (HTC) is an effective method for the harmless disposal of municipal sludge (MS) and offers potential applications for the obtained products. Optimizing reaction conditions, coupling with other waste materials, and combining different processes can improve the performance of HTC. Furthermore, HTC contributes to energy recovery and enhances the quality of life cycle assessment.
FUEL PROCESSING TECHNOLOGY
(2024)
Article
Chemistry, Applied
Jia Wang, Jianchun Jiang, Dongxian Li, Xianzhi Meng, Arthur J. Ragauskas
Summary: This study presents a scalable process for converting holocellulose and cellulosic wastes into advanced oxygen-containing biofuels with high furan, cyclic ketone, and ethanol content. By combining hydropyrolysis and vapor-phase hydrodeoxygenation using Pd/Al2O3 as a catalyst, the researchers achieved high yields and conversions. The integrated process holds great promise for biomass waste conversion into advanced biofuels.
FUEL PROCESSING TECHNOLOGY
(2024)
Article
Chemistry, Applied
Florian Held, Jannis Reusch, Steffen Salenbauch, Christian Hasse
Summary: The accurate prediction and assessment of soot emissions in internal combustion engines are crucial for the development of sustainable powertrains. This study presents a detailed quadrature-based method of moments (QMOM) soot model coupled with a state-of-the-art flow solver for the simulation of gasoline engines. The model accurately describes the entire cause-and-effect chain of soot formation, growth and oxidation. Experimental validation and engine cycle simulations are used to identify the root cause of observed soot formation hotspots.
FUEL PROCESSING TECHNOLOGY
(2024)
