Article
Engineering, Chemical
Saurabh Gupta, Santanu De
Summary: The hydrodynamics of a compact dual fluidized bed gasifier designed for high-ash coal were studied, investigating the effects of fluidization numbers from various aeration ports and secondary aeration on solids circulation rate and holdup. The study also looked into the performance of solids recycle systems for different types of solids discharge from the bubbling fluidized bed to the riser, affecting the density operation in the riser. An intense solids backmixing near the riser exit was observed for high gas velocity and high-density operation of the riser, which was alleviated by using secondary aeration.
Article
Engineering, Chemical
Ming Jiang, Yu Zhang, Yaxiong Yu, Qiang Zhou
Summary: A scale-independent modeling method for filtered drag force in fluidized gas-solid flows is proposed, showing excellent performance in a priori and a posteriori tests across different fluidized regimes. Correction methods to consider the material properties were tested but found to be unsuitable for the cases considered.
Article
Engineering, Chemical
Casey Q. LaMarche, Ray Cocco, S. B. Reddy Karri, Steven R. Dahl, Christine M. Hrenya
Summary: Measurements of gas-solid particle flow in a large-scale stripper unit are reported for the purpose of validating numerical methods for multiphase flow modeling. The experiments use a higher number of particles compared to previous studies and provide comprehensive measurement data.
CHEMICAL ENGINEERING SCIENCE
(2022)
Article
Engineering, Chemical
Yongli Wu, Qinfu Hou, Zheng Qi, Aibing Yu
Summary: The DEM-PNM approach couples discrete element method and pore network model to simulate particle-fluid flow. Reasonable flow patterns in gas fluidization and lateral gas injection were successfully simulated. However, the accuracy of the method is lower in dilute flow regions and some important factors are not considered.
CHEMICAL ENGINEERING SCIENCE
(2021)
Article
Engineering, Chemical
Pavitra Singh, Pankaj Kalita, Pinakeswar Mahanta, Plabon Tamuly
Summary: The SL-GSVR vortex reactor shows high heat and mass transfer efficiency, making it suitable for pharmaceutical and food processing industries, especially in food grain drying and preservation. Comparison between numerical and experimental results indicates improved bed uniformity, reduced system cost and complexity, as well as enhanced product quality in the SL-GSVR reactor.
JOURNAL OF THE TAIWAN INSTITUTE OF CHEMICAL ENGINEERS
(2021)
Article
Engineering, Chemical
Aristeidis Nikolopoulos, Christos Samlis, Myrto Zeneli, Nikos Nikolopoulos, Sotirios Karellas, Panagiotis Grammelis
Summary: Particles tend to clog and aggregate under fluidization conditions, forming meso-scale structures that affect gas-solid transport phenomena. The use of an ANN-EMMS drag scheme in CFD modeling shows improved accuracy in predicting pressure drop and CO2 concentration compared to conventional methods.
CHEMICAL ENGINEERING SCIENCE
(2021)
Article
Engineering, Environmental
Jethro Daniel Pascasio, Sunki Chung, Mokyeon Cho, Jaeyoung Lee
Summary: This article discusses the development strategies for electrochemical nitrogen reduction reaction (eNRR), including catalyst design, electrolyte, and reactor types. It provides new insights into the scale-up science for eNRR and the future commercialization of the electrocatalytic ammonia synthesis process.
CHEMICAL ENGINEERING JOURNAL
(2023)
Article
Physics, Multidisciplinary
Abram H. Clark, Emily E. Brodsky, John Nasrin, Stephanie E. Taylor
Summary: We computationally study the frictional properties of sheared granular media subjected to harmonic vibration applied at the boundary. We find that weakening requires the absolute amplitude squared of the displacement to be sufficiently large relative to the confining pressure and that a previously unrecognized second process dependent on dissipation contributes to shear weakening under vibrations. This analysis provides a basis for predicting flows subjected to arbitrary external vibration.
PHYSICAL REVIEW LETTERS
(2023)
Article
Thermodynamics
Pavitra Singh, Pinakeswar Mahanta, Pankaj Kalita
Summary: This study focuses on enhancing fluidization capacity and optimizing a lab-scale gas-solid vortex reactor without-slit numerically. By increasing the length to diameter ratio (L/D) from 0.2 to 1.2, the reactor capacity of the lab-scale GSVR reactor was significantly enhanced.
INTERNATIONAL COMMUNICATIONS IN HEAT AND MASS TRANSFER
(2021)
Article
Engineering, Chemical
Musango Lungu, John Siame, Lloyd Mukosha
Summary: The study uses the open source code MFIX to conduct CFD-DEM and TFM simulations of a fluidized bed experiment. Results show similar predictive capabilities of both modeling approaches for flow characteristics and particle velocity distribution, but differences in pressure drop and fluctuating quantities predictions. TFM simulations demonstrate more accurate predictions of particle granular temperature, while CFD-DEM simulations perform closer to experimental values. Overall, CFD-DEM simulations take twice as long as TFM simulations.
Article
Chemistry, Analytical
Jonas Koch, Daniel Scheps, Matthias Gunne, Oliver Boscheinen, Christian Frech
Summary: In the process development and characterization, scaling up chromatographic steps is challenging due to the assumptions of constant column properties. This work demonstrates the scalability to larger column volumes by applying a mechanistic model calibrated with a pre-packed 1 ml column. The model's relationship between the normalized gradient slope and the eluting salt concentration enables successful scaling with similar eluting salt concentrations, peak heights, and shapes. Improved predictions are achieved by considering radial inhomogeneities in packing quality in scale-up simulations.
JOURNAL OF SEPARATION SCIENCE
(2023)
Article
Engineering, Chemical
Masayuki Horio, Takami Kai, Takuya Tsuji, Hiroyuki Hatano
Summary: This paper provides an overview of the development of fluidization technology in Japan over the past 100 years. Japan was an early adopter of Winkler coal gasification technology and a participant in the formation of chemical engineering. However, it lagged behind in the development of fluidized catalytic cracking technology due to worsening international relations. Academic research on fluidization began in Japan in 1952. The paper reviews the global progress of chemical engineering and fluidization research, discusses the three-stage scheme in the development of fluidization knowledge, and reviews the research and technological developments in post-war Japan.
Article
Thermodynamics
Pavitra Singh, Pinakeswar Mahanta, Pankaj Kalita
Summary: The main objective of this study is to develop a best-performing gas-solid vortex reactor (GSVR) dryer and compare the effect of spiral versus conical chimney outlet on capacity enhancement. The computational fluid dynamics analysis showed that the solid loading capacity of the GSVR with a spiral chimney is 27% higher than that with a conical chimney. Additionally, capacity enhancement appears to be simpler and easier with a spiral chimney outlet due to its symmetric nature of construction.
INTERNATIONAL COMMUNICATIONS IN HEAT AND MASS TRANSFER
(2021)
Article
Engineering, Chemical
Ted M. Knowlton, Dale L. Keairns, Wen -Ching Yang
Summary: This paper primarily discusses the development of fluidization in North America in the 20th century. It chronicles the development of fluidization from the early 1920s to the early 2000s, focusing on the influence of Fluid Catalytic Cracking and World War II in jump-starting fluidization in the 1940s. The paper also explores the contribution of universities in the United States and Canada to the fluidization community, as well as historical controversies regarding pneumatic conveying and fluidized bed jets.
Article
Energy & Fuels
Shaoqi Chen, Ruixuan Li, Keying Ma, Yuanyuan Shao, Jesse Zhu
Summary: A new pilot-scale gas-driven inverse liquid-solid fluidized bed with a central draft tube (GDFB-II) was studied. The hydrodynamic characteristics of the GDFB-II were carefully studied using particles of different diameters and densities. Three flow regimes including packed bed, fluidized bed, and circulating bed regimes were identified and demarcated by the initial fluidization gas velocity (U-g, U-if) and the minimum circulating gas velocity (U-g, U-mc). The effects of the draft tube diameter and the gas injection tube diameter on the system behavior were also investigated.
CHEMICAL ENGINEERING AND PROCESSING-PROCESS INTENSIFICATION
(2022)
Article
Energy & Fuels
Yuxin Liu, Wenlei Dong, John Chew, Michael Pekris, Benzhuang Yue, Xiaozhi Kong
Summary: This article presents a new design of the front plate of a brush seal to mitigate the slipping of bristles caused by highly swirling inlet flow in gas turbine engines. Computational fluid dynamics is used to investigate the effects of angled ribs on the swirl and flow channeling of the bristle pack. The results show that ribs inclined at 20 degrees and with a height-to-spacing ratio of 0.4 are the most effective for the seal geometry under study. The findings have significant implications for brush seal design and can mitigate operational risk of swirl-induced instability.
FRONTIERS IN ENERGY RESEARCH
(2022)
Article
Engineering, Chemical
Allan S. Issangya, S. B. Reddy Karri, Ray A. Cocco, Ted Knowlton, Jia Wei Chew
Summary: This study measures the density and solid flux profiles of CFB risers, and discovers different types of solid flow patterns and multiple fluidization regimes. The findings suggest that commercial FCC risers may operate in similar regimes as observed in this study.
CANADIAN JOURNAL OF CHEMICAL ENGINEERING
(2023)
Review
Engineering, Environmental
Allan S. Issangya, Ray Cocco, Jia Wei Chew
Summary: Fluidized bed strippers are important in FCC and fluid coking processes. They can effectively remove hydrocarbon vapors from catalyst particles, preventing product loss and high temperatures in the regenerator. Various types of baffles are used in these strippers. Disk and donut strippers in FCC applications have been the focus of attention. Previous studies have investigated stripping efficiency, solids mass flux, stripping gas velocity, flooding, and other flow dynamics issues. Commercial stripper operating problems have been identified and diagnostic methods have been proposed. However, fundamental theories on mass transfer in strippers are lacking.
CHEMICAL ENGINEERING JOURNAL
(2023)
Article
Engineering, Chemical
Huang Teik Lay, Chi Siang Ong, Rong Wang, Jia Wei Chew
Summary: The study demonstrates that the DLVO approximation methods used to predict interfacial foulant-membrane interactions are sensitive to the boundary condition assumptions. Both the Poisson-Boltzmann (P-B) and linear superposition approximation (LSA) equations can quantify electrostatic interaction energy, but the LSA equation provides more accurate predictions in various filtration tests.
JOURNAL OF MEMBRANE SCIENCE
(2023)
Article
Chemistry, Physical
Meilan Pan, Junjian Li, Xue Zhang, Subiao Liu, Jia Wei Chew, Bingjun Pan
Summary: The introduction of axial coordination in the Co-N-4 site of single-atom cobalt catalyst can alter its spatial structure and transform it into an active center, leading to improved catalytic activity. The catalyst with axial coordination showed higher reaction kinetics and turnover frequencies in the electroreduction of nitrobenzene.
JOURNAL OF MATERIALS CHEMISTRY A
(2023)
Article
Engineering, Environmental
Fuweng Zhang, Kaiqiao Wu, Damiano La Zara, Michael J. Quayle, Feilong Sun, Gunilla Petersson, Staffan Folestad, Jia Wei Chew, J. Ruud van Ommen
Summary: By depositing different materials as nanoscale films onto micronized budesonide powders using atomic/molecular layer deposition (ALD/MLD) coatings, the flow properties of the powders can be altered and improved. Inorganic nanofilms deposited via ALD can reduce inter-particle forces, leading to improved drug delivery performance.
CHEMICAL ENGINEERING JOURNAL
(2023)
Article
Energy & Fuels
Juan Pablo Santana, Carlos I. I. Rivera-Solorio, Jia Wei Chew, Yong Zen Tan, Miguel Gijon-Rivera, Ivan Acosta-Pazmino
Summary: Numerical simulations were conducted to evaluate the technical and economic feasibility of a solar water desalination system using a hybrid CPVT collector and a VMD process. The CPVT collector with a triangular receiver and PV cells facing the reflecting surface was found to be advantageous in generating more electricity with less surface area. The optimal surface area of collectors and input temperature of the VDM module were determined through parametric analysis.
Article
Engineering, Chemical
Henry J. Tanudjaja, Angie Qi Qi Ng, Jia Wei Chew
Summary: Protein fouling is a complex mechanism and this study used the Random Forest (RF) and Neural Network (NN) models to determine the relative influences of parameters on fouling. Results showed that membrane pore size is the most dominant influence, followed by transmembrane pressure. The NN model demonstrated modest predictive capability despite inconsistencies in experimental setups.
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
(2023)
Article
Environmental Sciences
Meilan Pan, Xue Zhang, Junjian Li, Jia Wei Chew, Bingjun Pan
Summary: In this study, a heterogeneous MoS2-coated S,N-graphene (SNG) membrane (O-MoS2@SNG) was developed through a facile strategy. The electrochemical performance of O-MoS2@SNG was optimized and exhibited superior electrocatalytic performance (>90%) of bi-sphenol A with a large permeation volume in the online electrofiltration system.
Review
Engineering, Environmental
Casey Q. LaMarche, Ben Freireich, Ray Cocco, Jia Wei Chew
Summary: Numerical methods like computational fluid dynamics (CFD) for predicting multiphase flow involving solid particles offer promising benefits to a wide range of applications. Accurate representation of the fluid-particle momentum exchange, i.e., the drag and buoyancy forces, is crucial for studying fluid-particle hydrodynamics. However, there is a lack of widely accepted guidance on the most appropriate drag correlations for flow past homogeneous suspensions of spherical particles with narrow size distributions. This review addresses this gap and highlights the need for further development and validation of drag models in industrial fluid particle flows.
CHEMICAL ENGINEERING JOURNAL
(2023)
Article
Engineering, Chemical
Jia Zheng Oor, Chi Siang Ong, Yong Zen Tan, Jia Wei Chew
Summary: A covalent organic framework (COF) - incorporated thin film composite (TFC) membrane was successfully fabricated by in-situ formation of benzene-1,3,5-tricarboxaldehyde (TFB) and graphene oxide (GO) in p-Cymene. The resulting PES-COF-GO membrane exhibited high solvent permeance and separation efficiency in organic solvents.
JOURNAL OF MEMBRANE SCIENCE
(2023)
Review
Biochemistry & Molecular Biology
Yong Zen Tan, Nur Hashimah Alias, Mohd Haiqal Abd Aziz, Juhana Jaafar, Faten Ermala Che Othman, Jia Wei Chew, Chii-Dong Ho
Summary: Nanofibrous membranes have shown promise in membrane distillation for water and wastewater treatment, but fouling and wetting are still critical issues. This mini-review discusses the understanding and limitations of fouling in membrane distillation, including organic, inorganic, and biofouling. It also highlights progress in developing anti-fouling nanofibrous membranes and modifications for improved performance. Challenges and future directions for developing anti-fouling nanofiber membranes for membrane distillation are systematically addressed.
Review
Chemistry, Multidisciplinary
Yan Liu, Yun Tian, Jianda Xu, Changfu Wang, Yun Wang, Dingzhong Yuan, Jia Wei Chew
Summary: This review summarizes the recent research progress on graphene-based electrodes in the field of ion electrosorption, especially in water desalination utilizing capacitive deionization (CDI) technology. The latest advances in graphene-based electrodes, such as 3D graphene, graphene/metal oxide composites, graphene/carbon composites, heteroatom-doped graphene, and graphene/polymer composites, are presented. Furthermore, the challenges and future possible developments in the electrosorption area are also addressed, providing insights for researchers to design graphene-based electrodes towards practical applications.
Article
Environmental Sciences
Kai K. Chen, Weiyi Li, Jia Wei Chew
Summary: This study systematically evaluated the filtration capability of NF-like membranes with different combinations of PAH- and PVAm-containing bilayers in an FO process. It was found that increasing the PVAm content in the upper part of the active layer resulted in decreased water permeability and rejection of divalent salts. The membrane coated solely with PVAm-containing bilayers exhibited the fastest flux decline in fouling tests with SA, but the fouling layer was more easily removed by crossflow. OCT characterization showed that the bridging effect of divalent cations promoted the aggregation of SA, forming a particulate layer more susceptible to shear effect. These findings provide insights for improving NF-like FO by regulating the formation of the active layer via LbL assembly.
Review
Chemistry, Physical
Yi Mou, Xingzhong Yuan, Haoyun Chen, Yi Yang, Huan Dai, Jing Bai, Junying Chen, Jia Wei Chew, Hou Wang, Yan Wu
Summary: Rapid industrialization and population growth have led to an unprecedented demand for safe and reliable water supplies. Traditional sewage treatment technology can no longer meet the increasingly strict standards for safe drinking water. Reticular materials have gained interest in water treatment due to their adjustable aperture, and their design and synthesis with water stability are analyzed in this review. The latest research progress of reticular materials in wastewater treatment technologies is also discussed. This review is expected to help with the design and development of reticular materials for successful water treatment.
JOURNAL OF MATERIALS CHEMISTRY A
(2023)
Article
Engineering, Chemical
Ri Zhang, Shasha Zhang, Mengyan Ding
Summary: A thin liquid film method is proposed to evaluate sand erosion in annular flow. This method considers the direct interaction between the liquid film and gas core, as well as the entrainment and deposition of droplets. The erosion rate is calculated by considering the effects of liquid entrainment and particle velocity decay. The method is fully verified by comparing with experimental data.
Article
Engineering, Chemical
Yu Suo, Xianheng Su, Wenyuan He, Xiaofei Fu, Zhejun Pan
Summary: This research investigates the mechanical properties of sandstone-shale composite through orthogonal experimental method and discrete element simulation. The results show that different lithologies and thickness ratios can affect the strength and fracture mode of the composite rock samples.
Article
Engineering, Chemical
Maurizio Troiano, Andrea El Hassanin, Roberto Solimene, Alessia Teresa Silvestri, Fabrizio Scala, Antonino Squillace, Piero Salatino
Summary: This study investigates the potential of Fluidized Bed Finishing (FBF) for square flat AlSi10Mg specimens manufactured via Laser-Powder Bed Fusion (L-PBF) additive manufacturing technology. The results show that good finishing can be achieved using rotation-assisted tests, with a maximum reduction of surface roughness by 67%. Steel particles are found to be the most effective bed material.
Review
Engineering, Chemical
Ningbo Song, Wanzhong Yin, Jin Yao
Summary: Seawater's dissolved salts and minerals have various effects on the flotation process, including influencing the characteristics and behavior of flotation factors, as well as affecting the surface of sulfide minerals. In most cases, seawater has adverse effects on the flotation of sulfide minerals, but these effects can be mitigated by adjusting the reagents.
Article
Engineering, Chemical
Kaiqiao Wu, Shuxian Jiang, Victor Francia, Marc-Olivier Coppens
Summary: In rectangular and cylindrical annular fluidized beds, pulsating gas flow can create regular bubble patterns, overcoming challenges seen in conventional units. This study provides new opportunities for modularization of fluidized bed operations.
Article
Engineering, Chemical
Shuo Li, Huili Zhang, Jan Baeyens, Miao Yang, Zehao Li, Yimin Deng
Summary: The paper assesses the behavior of cohesive Geldart C-type particles when fluidized by air with the aid of vibration. It determines that mechanical vibration is a simple and effective method to improve the fluidity of cohesive particles during fluidization.
Article
Engineering, Chemical
Zhenfei Feng, Qingyuan Zhang, Shanpan Liang, Zhenzhou Li, Fangwen Guo, Jinxin Zhang, Ding Yuan
Summary: A new micro/mini-channel heat sink (MCHS) with a combined structure of longitudinal and transverse vortex generators is designed, using Al2O3 nanofluid as the working medium. The study explores the effects of transverse vortex generator shape and longitudinal vortex generator angle on the hydraulic and thermal characteristics, comprehensive performance, entropy generation, and exergy efficiency. The results show that the triangular transverse vortex generator improves the comprehensive performance and exergy efficiency. Combined with the longitudinal vortex generator, the MCHS achieves the best comprehensive performance, entropy generation, and exergy efficiency when the Reynolds number is 742.
Article
Engineering, Chemical
Kostas Giannis, Christoph Thon, Guoqing Yang, Arno Kwade, Carsten Schilde
Summary: This study presents a 3D convolutional neural network (3D-CNN) methodology for generating realistic 3D models of particles. The method trains on 2D projections of particle images to predict their 3D shapes, and evaluates the accuracy of the predictions using Fourier shape descriptors (FSDs). This methodology has wide applications in particle shape analysis.
Article
Engineering, Chemical
Zheng-qing Zhou, Lu-jia Chai, Yu-long Zhang, Ya-bin Wang, Ze-chen Du, Tian-yi Wang, Yu-zhe Liu
Summary: The dynamic oxidation and shell-breaking processes of aluminum nanoparticles (ANPs) during heating were studied using in situ transmission electron microscopy. The results revealed that the changes in shell thickness can be divided into three stages, and the active aluminum content of ANP decreased before shell-breaking.
Article
Engineering, Chemical
Fulei Chen, Huaqing Ma, Zihan Liu, Lianyong Zhou, Yongzhi Zhao
Summary: A particle breakage model based on the particle replacement scheme, using the polyhedral model to describe particles, is proposed in this work to accurately describe the breakage of a large number of particles. Additionally, a fast-cutting algorithm is proposed to reproduce the size distribution of progeny particles determined by the breakage model. The validation and simulation results show satisfactory accuracy, efficiency, and stability of the algorithm.
Review
Engineering, Chemical
Matteo Errigo, Christopher Windows-Yule, Massimiliano Materazzi, Dominik Werner, Paola Lettieri
Summary: Gas-solid fluidized-bed systems have advantages in terms of chemical reaction efficiency and temperature control, making them widely used in industrial applications. However, the design, scale-up, and optimization of these complex units are limited by the lack of deep physical understanding. Non-invasive and non-intrusive diagnostic techniques provide a way for researchers to study these systems without affecting the flow field or directly contacting the medium under study.
Article
Engineering, Chemical
Saeed Fateh, Mohammad Behshad Shafii, Mohammad Najafi, Cyrus Aghanajafi
Summary: Applying a magnetic field to ferrofluids alters their flow characteristics and enhances heat transfer. Through visualization and quantitative investigation, it is found that the magnetic field influences the flow patterns and velocity profiles, improving fluid mixing and vorticity magnitude.
Article
Engineering, Chemical
Lei Gao, Bingbing Wei, Xiaochuan Hu, Zaifeng Yao, Yiwen Fang, Xuejian Gao
Summary: In this study, a numerical model of sand triaxial test was established using discrete element software PFC3D, and an indoor triaxial test was conducted to calibrate the numerical model. The influence of microscopic parameters on the macroscopic mechanical response of sand was analyzed. The results showed that the friction coefficient had the greatest impact on the peak strength and residual strength of the sand's stress-strain curve, and it was positively correlated. The normal tangential stiffness ratio was negatively correlated, while the porosity and boundary flexibility stiffness had minimal influence on it.
Article
Engineering, Chemical
Xuan Liu, Jie Gong, Kai Jiang, Xiaojuan Lai, Yu Tian, Kang Zhang
Summary: This study aimed to improve the performance of lignite coal water slurries (CWSs) by synthesizing a series of three-arm amphiphilic block copolymers. By controlling the relative molecular weight, hydrophilic/hydrophobic ratio, and ionic group content, the apparent viscosity of CWSs was significantly reduced and the static stability was improved. Thermogravimetric testing and XPS analysis were conducted to reveal the mechanism behind the improved performance.
Article
Engineering, Chemical
Lanka Dinushke Weerasiri, Daniel Fabijanic, Subrat Das
Summary: Fluidization at low pressure offers significant benefits for the fine chemical industry. This study investigates the behavior of bubbles and bed expansion under low pressure conditions. It is found that lower pressure leads to larger bubbles, increased bubble quantity, and higher aspect ratio. The predictability is affected by the inhomogeneous fluidization, but low pressure fluidization can generate similar bubble sizes with lower fluidizing mass compared to atmospheric pressure.