Article
Engineering, Chemical
Jingwei Geng, Zhuo Yang, Yujie Tian, Bona Lu, Wei Wang
Summary: To investigate the effects of macroscale constraints on fluidization, fine-grid simulations were used to compare the periodic domain and realistic bed. The differences were highlighted by examining force balance conditions in the gas-phase, solid-phase, and mixture. The influence of the bounding wall was implicitly included through markers such as gas-phase pressure gradient and turbulent kinetic energies.
CHEMICAL ENGINEERING SCIENCE
(2023)
Article
Engineering, Chemical
Chunhua Zhang, Bona Lu, Xiaoshuai Yuan, Hua Li, Mao Ye, Wei Wang
Summary: This study investigated the effects of kinetic models and coke content on the reactive predictions of MTO fluidized beds, identifying the underlying reasons for the deviation from experimental results. It was found that coke content distribution plays a critical role in reaction predictions, and considering a reasonable coke content distribution led to better predictions in methanol conversion and selectivity to light olefins.
Article
Engineering, Chemical
Zhuo Yang, Bona Lu, Wei Wang
Summary: In this study, a generic EMMS drag model was developed using Artificial Neural Network (ANN) to simulate dense fluidized beds under a wide range of operating conditions and material properties. The model's algorithm was optimized to efficiently provide a large dataset and the performance of ANN was tested by training with different numbers of data and hidden layer structures. The EMMS-ANN model showed reasonable prediction and good applicability to a wide range of dense fluidization.
CHEMICAL ENGINEERING SCIENCE
(2021)
Article
Engineering, Environmental
Zheng Zou, Yu Ge, Jingyi Zhu, Junwu Wang, Qingshan Zhu, Hongzhong Li
Summary: This study analyzed the application of MCFBR for the reduction of MnO2 ore and established a computational model for the hydrodynamics and reaction characteristics of multi-chamber fluidized bed. The simulation results showed that the model could accurately calculate the gas-solid reaction behavior compared to the traditional model. Furthermore, the quantitative effects of partition configuration, fluidized structure, and operating condition on the solids conversion rate were estimated.
CHEMICAL ENGINEERING JOURNAL
(2023)
Article
Engineering, Chemical
Areej Javed, Yongli Ma, Mingyan Liu
Summary: A flow model for the gas-liquid-solid circulating fluidized bed with a mesoscale flow structure has been established in this study. The study validates the bubble hydrodynamics calculated by the energy-minimization multiscale model using empirical correlations. The results show that the drag coefficient has a significant impact on bubble hydrodynamics, and the new EMMS model offers the best agreement with experimental data.
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
(2022)
Article
Engineering, Chemical
Caixia Han, Youhao Xu, Bona Lu, Hao Wu, Wei Wang
Summary: This study investigates the flow regime transition and regulation mechanism in diameter-transformed reactors using multiscale CFD simulations and twelve-lump kinetics. The results show that a high-concentration choking plateau appears in the new reactor when considering reactions, while it becomes a slowly ascending slope under cold-model conditions. Changing the particle circulating mode can stabilize the flow behaviors and product yield.
Article
Engineering, Chemical
Xingchi Liu, Aiqi Zhu, Lina Yang, Ji Xu, Hua Li, Wei Ge, Mao Ye
Summary: Particle scale information of commercial fluidized beds is crucial for their design and optimization, but difficult to obtain accurately through in-situ measurements or continuum-based numerical simulations. This study integrates the newly developed MTO reaction model with the EMMS-DPM method to investigate the evolution of coke content distribution on catalysts and optimize the operation of a commercial MTO reactor.
Article
Engineering, Chemical
Jingwei Geng, Yujie Tian, Wei Wang
Summary: In this work, a two-level averaging approach is proposed for mesoscale drag modeling in gas-solid fluidization. The method defines the mean drag at the fine-grid scale and the unified EMMS drag at the coarse-grid scale by performing a series expansion with respect to the phase mean points. The effectiveness of the method is validated through comparisons with simulations at different scales.
CHEMICAL ENGINEERING SCIENCE
(2022)
Article
Engineering, Chemical
Li-Tao Zhu, He Lei, Bo Ouyang, Zheng-Hong Luo
Summary: This work systematically investigates the applicability of mesoscale drag models in various flow regimes and optimizes the operational and fluidization quality of a fluidized bed reactor through bed internals design and evaluation of bed size effects.
CHEMICAL ENGINEERING SCIENCE
(2022)
Article
Green & Sustainable Science & Technology
Mukesh Upadhyay, Vijay Mohan Nagulapati, Hankwon Lim
Summary: Circulating fluidized bed (CFB)-based co-pyrolysis is a potential technology for producing synthetic fuel and chemical co-products. Computational fluid dynamics (CFD) tools are valuable for understanding gas-solid flow hydrodynamics and optimizing reactor operations. This study developed an artificial neural network (ANN) model based on a wide CFD simulation campaign to predict axial solid holdup in CFB riser. The ANN model showed good performance and low mean square error values when compared with experimental data.
JOURNAL OF CLEANER PRODUCTION
(2022)
Article
Chemistry, Multidisciplinary
Riccardo Uglietti, Daniele Micale, Damiano La Zara, Aristeidis Goulas, Luca Nardi, Mauro Bracconi, J. Ruud van Ommen, Matteo Maestri
Summary: This study demonstrates the potential of combining numerical and experimental approaches in understanding catalytic reactors, particularly fluidized beds. Through experiments and data analysis, the effectiveness of the in-house first-principles multiscale Computational Fluid Dynamic-Discrete Element Method (CFD-DEM) model is validated, and the fundamental insights that can be achieved through detailed numerical methods are reported. The integration of experimental information and numerical simulations allows for optimal design and scale-up procedures for reactor configurations with promising prospects in the energy transition.
REACTION CHEMISTRY & ENGINEERING
(2023)
Article
Engineering, Environmental
Chunhua Zhang, Bona Lu, Wei Wang, Mengxi Liu, Chunxi Lu, Mao Ye
Summary: In this study, a population balance model (PBM) combined with multiscale computational fluid dynamics (CFD) was used to simulate the evolution of coke distribution in a methanol-to-olefins fluidized bed reactor. The predicted wide and uneven distribution of coke content showed good agreement with experimental data. The mass fractions of the desired products, ethylene and propylene, and their selectivity ratio were also well predicted. The reasonable prediction suggests that coupling PBM with multiscale CFD is helpful to understand and optimize MTO reactors.
CHEMICAL ENGINEERING JOURNAL
(2022)
Article
Engineering, Chemical
Ping Li, Nana Wang, Ruiyang Xu, Jianmin Chang, Hui Si
Summary: This study explores the pneumatic feeding characteristics of a fluidized bed to enhance understanding of biomass pyrolysis. By analyzing the pneumatic feeding mechanism from aspects including feed gas, feed biomass particles, and pneumatic feeding, it is revealed how the feed gas promotes particle diffusion, mixing, and deeper penetration into the bed. A dynamic model of pneumatic feeding into the fluidized bed reactor is established to integrate particle interaction, diffusion, mixing, and fluidization.
Article
Engineering, Chemical
Ehsan Zhalehrajabi, Kok Keong Lau, Thomas Hagemeier, Alamin Idris
Summary: The hydrodynamics of urea fluidized bed were simulated using CFD and image processing technique. Sensitivity analyses on model parameters were conducted to select the appropriate drag models. The results showed that the predictions of Gidaspow model for particle velocity and granular temperature were in good agreement, while the predictions of Syamlal-O'Brien model were underestimated. Further analysis indicated that particle velocity increased with higher air inlet velocity and decreased with larger particle sizes. The study also highlighted the importance of considering humidity at high pressures.
Article
Engineering, Chemical
Hao Zhang, Wanbing Qiao, Xizhong An, Xinglian Ye, Jiang Chen
Summary: This study investigates the fluidization characteristics of a gas-solid fluidized bed reactor containing ternary particles using coupled computational fluid dynamics and discrete element method simulations. The results show that increasing the superficial gas velocity can enhance the overall mixing degree and mitigate the discrepancy caused by particle shape.
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
Hao Luo, Xiaobao Wang, Xiaoqin Wu, Lukasz Niedzwiecki, Halina Pawlak-Kruczek, Xinyan Liu, Qingang Xiong
Summary: The multi-fluid model is commonly used to study heat transfer between gas and solid in bubbling fluidized beds, but it is difficult to implement a one-dimensional model considering intra-particle temperature inhomogeneity. To solve this issue, a corrected coefficient is introduced to quantitively feature the effects of intra-particle temperature inhomogeneity on external heat transfer, forming a corrected zero-dimensional model. The results show that the corrected model predicts the temperature profiles more accurately and has comparable computational efficiency compared to the original model.
CHEMICAL ENGINEERING JOURNAL
(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
Engineering, Environmental
Chuanpeng Zhang, Renshuai Zhu, Yanpei Chen, Wei Wang, Tomohiko Furuhata
Summary: The configuration-dependent dynamics of non-spherical particles were experimentally investigated in a quasi-two-dimensional gas-solid fluidized bed. It was found that the vertical velocity profiles were sensitive to the aspect ratio at low gas velocity but not at high gas velocity. The velocity distribution, particularly the rotational velocity distribution, deviated from the Maxwellian distribution. The joint probability density distribution of vertical and rotational velocity was asymmetric. Two high-probability particle configurations, two particles in a parallel or vertical arrangement, were identified by calculating various functions. The cause of this order appearance was explained through entropy theory. The drag force of the particle configurations at different angles and Re was compared, demonstrating the necessity of considering configuration-dependent drag force for non-spherical particle fluidization.
CHEMICAL ENGINEERING JOURNAL
(2023)
Article
Engineering, Environmental
Zhiwei Wang, Jiaying Huang, Wei Wang, Xinfeng Wang, Yan Wang, Baoyu Gao, Qian Li
Summary: Monocarboxylic acids were used to modulate the number of missing-linker defects in Hf-porphyrin MOFs (Hf-TCPP-X) and enhance their performance in removing norfloxacin from complex aqueous matrices. The missing-linker defects promoted the removal efficiency by facilitating photoinduced charge transfer and increasing the number of active sites. This study provides a promising route to improve the removal performance of contaminants in highly saline water through defect engineering.
CHEMICAL ENGINEERING JOURNAL
(2023)
Article
Energy & Fuels
Ivana Stanicic, Emil Ola Lidman Olsson, Hao Wu, Peter Glarborg, Inaki Adanez-Rubio, Henrik Leion, Tobias Mattisson
Summary: In this study, the interaction between zinc compounds and ilmenite particles was investigated by exposing three types of ilmenites to gas-phase Zn and ZnCl2. The results showed that the gaseous conditions, particle ash layer composition, and iron availability played an important role in the interaction between zinc compounds and ilmenite particles.
Review
Energy & Fuels
Emil O. Lidman Olsson, Peter Glarborg, Kim Dam -Johansen, Hao Wu
Summary: Phosphorus is essential for all life and its levels in biomass can cause operational problems in biomass thermal conversion. This study provides a comprehensive review of phosphorus chemistry and fate during biomass conversion. It includes an introduction to phosphorus in biomass, analytical techniques for phosphorus characterization, classification of phosphorus-rich biomass, and an overview of phosphorus transformations in biomass. The review also covers research on phosphorus in different application aspects, such as corrosion and the deactivation of SCR catalysts.
Article
Energy & Fuels
Arphaphon Chanpirak, Hao Wu, Peter Glarborg, Paul Marshall
Summary: This study investigates the effect of KCl on moist CO oxidation in a laminar flow quartz reactor. Experiments are conducted under various conditions and the results are interpreted using a chemical kinetic model. It is found that KCl reacts with SiO2 on the quartz surface, altering its condition and enhancing catalytic activity. The inhibition of CO oxidation is mainly attributed to the loss of hydrogen atoms on the reactor wall and gas-phase reactions, depending on the conditions. The most important reaction for inhibition is the chain terminating step KO2 + OH ⇆ KOH + O2, which is controlled by long-range dipole-dipole interactions.
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
Energy & Fuels
Arphaphon Chanpirak, Hamid Hashemi, Flemming J. Frandsen, Hao Wu, Peter Glarborg, Paul Marshall
Summary: In this study, the chemical coupling between moist CO oxidation and transformation of gaseous potassium salts in the presence or absence of SO2 was investigated. Experimental results showed that both KCl and KOH inhibited CO oxidation, but the inhibiting effect was reduced by the addition of SO2. The degree of sulfation of KCl and KOH by SO2 was evaluated, and it was found that KCl was only sulfated to a small degree while KOH was fully sulfated according to the results.
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
Wei Huang, Chuntao Zhang, Zongqi Li, Wendong Liang, Jikun Xu, Qingang Xiong, Hao Luo
Summary: An Eulerian-Eulerian two-fluid model incorporating the kinetic theory of granular flow was used to study the heat transfer performance in continuous oscillatory baffled crystallizers (COBC) with solid-liquid two-phase flow. The results showed that the novel COBC #6 has excellent heat transfer and particle suspension performance compared to other COBCs, highlighting the importance of optimizing the chamber connection structure. The effects of operating conditions and particle physical properties on heat transfer performance were further investigated, with results indicating that increasing oscillation Reynolds number improves radial mixing and increases heat flux.
CHEMICAL ENGINEERING SCIENCE
(2023)
Article
Engineering, Chemical
Hao Luo, Xiaobao Wang, Xinyan Liu, Lan Yi, Xiaoqin Wu, Xi Yu, Yi Ouyang, Weifeng Liu, Qingang Xiong
Summary: A corrected zero-dimensional (Cor-0D) model was developed based on a one-dimensional model to accurately simulate the pyrolysis process inside thermally-thick biomass particles. Correction coefficients for external heat transfer, particle diameter, and pyrolysis reactions were introduced by comparing predictions of the one-dimensional model with the zero-dimensional model. An artificial neural network (ANN) was used to derive an ANN-Cor-0D model by correlating the correction coefficients with convective heat transfer coefficient, particle size, gas temperature, moisture content, and particle's dimensionless temperature. The results show that the ANN-Cor-0D model has the same performance as the Cor-0D model.
CHEMICAL ENGINEERING SCIENCE
(2023)
Article
Ecology
Adil Mehmood, Muhammad Wasim Tahir, Muhammad Azam Saeed, Muhammad Yousaf Arshad, Huma Hussain, Jakub Mularski, Lukasz Niedzwiecki
Summary: The depletion of fossil-based fuels and environmental deterioration require the aggressive development of renewable energy technologies. Biomass gasification is a promising approach, and CFD modeling shows potential in advancing gasification systems. Mixing CO2 with gasification agents is explored as a potential CCU strategy. The research investigates the effect of gasifying agent composition, air-to-steam ratio, oxygen, and CO2 mixing on the quality of syngas. The results suggest that a 50%-50% air-steam mixture produces the best quality syngas, while oxygen has a negligible impact, and a mixture of air-steam-CO2 = 23%-50%-15% is optimal for high-quality syngas.
Article
Thermodynamics
Agnieszka Urbanowska, Lukasz Niedzwiecki, Mateusz Wnukowski, Christian Aragon-Briceno, Malgorzata Kabsch-Korbutowicz, Marcin Baranowski, Michal Czerep, Przemyslaw Seruga, Halina Pawlak-Kruczek, Eddy Bramer, Gerrit Brem, Artur Pozarlik
Summary: Organic solid waste is a cost-effective biomass suitable for biogas production. Hydrothermal carbonisation can improve the moisture content of digestate and convert it into a higher-quality solid fuel. Membrane separation can treat the effluent by-product and increase the concentration of organic compounds while recovering clean water. The study using polymeric membranes showed that membrane separation retains a significant amount of organics in the retentate, increasing the biomethane potential and energy recovery from the concentrated retentate.
