Article
Energy & Fuels
Yinfei Liao, Zhe Yang, Maoyan An, Yijun Cao, Xiaodong Hao, Xingwei Song, Hourui Ren, Aosheng Yang, Luojian Chen
Summary: The study investigated the spreading behavior of different collectors in low-rank coal flotation, finding that the spreading speed and coefficient varied in a certain order. The molecular kinetic model provided insights into the contact angle relaxation and contact line movement during the spreading process.
Article
Energy & Fuels
Kanghao Zheng, Wenjun Zhang, Yijiang Li, An Ping, Feng Wu, Guangyuan Xie, Wencheng Xia
Summary: In this study, a coal tar-based collector was used to remove unburned carbon (UC) from fly ash through flotation process. The adsorption mechanism of the collector on the UC particle surface was characterized, and it was found that the oxygen-containing functional groups and aromatic ring compounds in the collector significantly enhanced the floatability of UC.
Article
Chemistry, Physical
Andre R. Augustyn, Robert W. M. Pott, Margreth Tadie
Summary: Surfactin, a biosurfactant, has been found to have both collecting and depressant characteristics on coal surfaces at different pH and concentration levels, showing potential as a green chemistry substitute for synthetic surfactants in froth flotation applications.
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
(2021)
Article
Energy & Fuels
Yinfei Liao, Zhe Yang, Maoyan An, Longfei Ma, Aosheng Yang, Yijun Cao, Luojian Chen, Hourui Ren
Summary: This study investigated the interaction between oil collector drop and coal particle in low-rank coal flotation. Different collectors were used and their interaction mechanisms were revealed through measurements such as wetting heats and FTIR analysis. The results showed that mixed collector obtained higher flotation efficiency.
Article
Green & Sustainable Science & Technology
Yinfei Liao, Maoyan An, Xiaodong Hao, Xingwei Song, Zhe Yang, Hourui Ren, Zechen Liu
Summary: This study investigated the feasibility of using surface functionalized polystyrene nanoparticles as collectors for low rank coal flotation. Different nanoparticles were prepared and characterized, with TFPNs and HFPNs showing significant improvement in flotation recovery compared to PNs and diesel oil. The results suggest that the surface functionalization degree plays a crucial role in enhancing the performance of nanoparticles in LRC flotation.
JOURNAL OF CLEANER PRODUCTION
(2021)
Article
Energy & Fuels
Yali Cheng, Fanfei Min, Hui Li, Jun Chen, Xiaoheng Fu
Summary: This study investigated the effects of reagent interaction on the performance of froth using a self-made test device. The results showed that different collectors and frothers had an impact on the foaming and stability of the froth, and the concentration of the reagent also affected the maximum foam height and half-life of the three-phase froth.
Article
Engineering, Chemical
Chun Yong Ng, Hangil Park, Liguang Wang
Summary: The study demonstrates the effectiveness of using sound for improving coal flotation performance. It shows that sound can enhance the final combustible recovery, flotation rate constant and separation efficiency rate in different operating conditions, without significant impact on product ash content.
MINERALS ENGINEERING
(2021)
Article
Chemistry, Physical
Siyuan Yang, Yanling Xu, Cheng Liu, Diallo A. D. Soraya, Chao Li, Hongqiang Li
Summary: The study found that the combined collector of NaOl and SPA in ilmenite flotation has a synergistic effect, leading to improved adsorption energy and collection performance.
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
(2021)
Article
Energy & Fuels
Hui Duan, Hong-hao Chang, Ling-xiao Gao, Yue-xian Yu, Xian-jun Lyu, Xiang-nan Zhu
Summary: This study investigated the influence of oxidation degree on the floatability and functional group composition of coal, and analyzed the feasibility of using waste engine oil as a renewable collector for fine coal flotation. FTIR analysis showed that oxidation degree had no significant effect on functional group types. However, XPS analysis indicated that with increasing oxidation degree, the content of C-C/C-H groups decreased significantly, leading to a notable decrease in floatability. The results also demonstrated that renewable collector could be successfully used for the flotation of fine coal, providing a potential alternative to eliminate the environmental threat of waste engine oil.
Article
Mining & Mineral Processing
S. A. Kondrat'ev, T. A. Khamzina
Summary: The literature review reveals that the time of induction is preferable to the wetting angle as a criterion for coal floatability. The authors analyze the kinetics of coal flotation based on the surface properties of heteropolar collectors in relation to the gas-liquid interface. The correlation between the spreading velocity of collectors on water surface and the coal flotation kinetics is determined using fat coal slurries as a case-study. It is found that the flotation activity of the collector is governed by its properties relative to the gas-liquid interface.
JOURNAL OF MINING SCIENCE
(2023)
Article
Engineering, Chemical
Liang Shen, Jiabao Gong, Yifang Liu
Summary: In this study, the combined method of grinding and collector gasification flotation was used to prepare ultra-clean coal. The effects of grinding time on coal samples were investigated, and the optimal conditions were determined. The results showed that this method achieved higher concentrate yield and lower concentrate ash content compared to the traditional flotation method.
Article
Engineering, Chemical
Mengni Zhang, Gan Cheng, Yang Lu, Yijun Cao, Ee Von Lau
Summary: This study introduces ozone and ultraviolet oxidation methods to modify waste cooking oil collector and analyzes their effects on the flotation performance of long-flame coal. Shorter ozone oxidation time resulted in better performance and higher separation efficiency compared to UV oxidation. UV oxidation increased the oxygen-containing functional groups in the collector and improved the reactions on the coal surface, leading to increased contact angle.
MINERALS ENGINEERING
(2023)
Article
Energy & Fuels
Gan Cheng, Mengni Zhang, Yang Lu, Haijun Zhang, Ee Von Lau
Summary: A novel emulsified waste fried oil collector (EWFOC) was prepared and compared to common collector (diesel) and waste fried oil collector (WFOC) in flotation experiments on low-rank coal. EWFOC showed better flotation performance, leading to a significant reduction in WFOC dosage and improved hydrophobicity of the coal. The improved performance of EWFOC is attributed to its stable dispersion and attachment to coal particles.
Article
Energy & Fuels
Mohana Rao Kadagala, Suresh Nikkam, Sunil Kumar Tripathy
Summary: This study examined the application of biodegradable collectors in high-ash oxidized Indian coal. The results showed that KP collectors had higher flotation efficiency and ash reduction rate, providing an important pathway for the effective separation of coking coal.
INTERNATIONAL JOURNAL OF COAL PREPARATION AND UTILIZATION
(2023)
Article
Energy & Fuels
Zhe Yang, Yinfei Liao, Maoyan An, Hourui Ren, Xiaodong Hao, Xingwei Song, Zechen Liu
Summary: WSMO is an effective collector for promoting LRC flotation by improving the hydrophobicity of the LRC surface and enhancing flotation efficiency.
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.