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Engineering â€ș Mechanical Engineering

Coal Combustion and Slurry Processing

Works Count: 29283

Description

This cluster of papers focuses on the technology and utilization of coal water slurry, including its rheological behavior, combustion characteristics, stability improvement using surfactants, environmental impact, utilization of petrochemicals, microwave irradiation for property enhancement, and waste material utilization for energy efficiency.

Keywords

Coal Water Slurry; Rheology; Combustion; Stability; Surfactants; Environmental Impact; Petrochemicals; Microwave Irradiation; Waste Utilization; Energy Efficiency

Sludge Reduction Technologies in Wastewater Treatment Plants

2010-01-01
Paola Foladori , Gianni Andreottola , Giuliano Ziglio
Sludge Reduction Technologies in Wastewater Treatment Plants is a review of the sludge reduction techniques integrated in wastewater treatment plants with detailed chapters on the most promising and most widespread 
 Sludge Reduction Technologies in Wastewater Treatment Plants is a review of the sludge reduction techniques integrated in wastewater treatment plants with detailed chapters on the most promising and most widespread techniques. The aim of the book is to update the international community on the current status of knowledge and techniques in the field of sludge reduction. It will provide a comprehensive understanding of the following issues in sludge reduction: principles of sludge reduction techniques;process configurations;potential performance;advantages and drawbacks;economics and energy consumption.This book will be essential reading for managers and technical staff of wastewater treatment plants as well as graduate students and post-graduate specialists.ISBN: 9781843392781 (Print)ISBN: 9781780401706 (eBook)
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Pulverized-Coal Combustion and Gasification

1979-01-01
L.D. Smoot , David T. Pratt

Analysis of Biogeochemical Cycling Processes in Walker Branch Watershed

1989-01-01
Dale W. Johnson , R.I. Van Hook

Proceedings of the 20th International Conference on Fluidized Bed Combustion

2010-01-01
Grace Gar‐Lee Yue , Hai Zhang , Changsui Zhao +1 more

Mathematical model for heat transfer limitations of heat pipe

2011-07-16
Patrik Němec , Alexander Čaja , Milan Malcho

Improving stability of concentrated coal–water slurry using mixture of a natural and synthetic surfactants

2013-04-10
Debadutta Das , Jibardhan Meher , Pramila Kumari Misra

The energetics of flocculation and redispersion by polymers

1964-04-01
Thomas W. Healy , Victor K. La Mer

Filtrational combustion of gases. Present state of affairs and prospects

1993-01-01
V. S. Babkin
Abstract Abstract
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Properties of sodium lignosulfonate as dispersant of coal water slurry

2007-06-07
Dongjie Yang , Xueqing Qiu , Mingsong Zhou +1 more

An experimental study of stability of oil–water emulsion

2004-08-24
Gonglun Chen , Daniel Tao

Combustion of coal–water suspensions

2010-10-31
Agnieszka Kijo–Kleczkowska

Effect of coal particle size distribution, volume fraction and rank on the rheology of coal–water slurries

2003-10-15
Feridun Boylu , Hatice Dinçer , GĂŒndĂŒz AteƟok

The Surface Characteristics and Reactivity of Residual Carbon in Coal Gasification Slag<sup>†</sup>

2009-08-19
Xianglong Zhao , Cai Zeng , Yanyan Mao +6 more
In a slagging entrained-flow coal gasifier, a large portion of the inorganic matter will form liquid slag that may have strong physical and chemical interactions with char. Understanding the char−slag 
 In a slagging entrained-flow coal gasifier, a large portion of the inorganic matter will form liquid slag that may have strong physical and chemical interactions with char. Understanding the char−slag interaction is important for improving the modeling and design of gasifiers. This paper reports the characteristics of residual carbon in both coarse and fine slag from a typical entrained-flow coal water slurry gasifier. The surface characteristics of slag and residual carbon in slag were evaluated by scanning electron microscopy and energy dispersive X-ray spectroscopy. The reactivity of the residual carbon in slag was compared through thermal gravimetric analysis. It was observed that fine inorganic matters in the slag tend to exist in spherical shape whereas residual carbons tend to stay as loose floccule. A melting test on fine carbon−slag mixture validated that inorganic matters have a tendency to agglomerate into large carbon-free spheres when melting in a carbon powder matrix due to surface tension change. It was also found that the reactivity of the carbon in fine slag was lower than carbon in coarse slag, which implies the formations of the carbon in fine and coarse slag are different.

Co-firing of oil sludge with coal–water slurry in an industrial internal circulating fluidized bed boiler

2009-01-27
Jianguo Liu , Xiumin Jiang , Lingsheng Zhou +2 more

Modeling and simulation of an entrained flow coal gasifier

1984-01-01
Rakesh Govind , Jogen Shah
Abstract A mathematical model has been developed to simulate the Texaco downflow entrained‐bed pilot‐plant gasifier using coal liquefaction residues and coal‐water slurries as feedstocks. This model describes the physical and 
 Abstract A mathematical model has been developed to simulate the Texaco downflow entrained‐bed pilot‐plant gasifier using coal liquefaction residues and coal‐water slurries as feedstocks. This model describes the physical and chemical processes occurring in an entrained coal gasifier. The gasification kinetics describes different complex reactions occurring in the gasifier and the hydrodynamics describes mass, momentum and energy balances for solid and gas phases. Temperature, concentration and velocity profiles along the reactor height were obtained by solving the mass, momentum and energy balances. Parameter studies were made to provide a better understanding of the reactor performance for various inlet feed conditions utilizing the model.

Fouling of heat exchangers

1997-05-01
T. R. Bott , L. F. Melo

Shedding of ash deposits

2008-11-21
Ana Ćœbogar , Flemming Frandsen , Peter Arendt Jensen +1 more

A method of calculating fluid inclusion volumes based on vapor bubble diameters and P-V-T-X properties of inclusion fluids

1983-05-01
Robert J. Bodnar

Numerical simulations of the slagging characteristics in a down-fired, pulverized-coal boiler furnace

2009-10-07
Qingyan Fang , Huajian Wang , Yan Wei +3 more

Effect of hydrothermal dewatering on the slurryability of brown coals

2012-01-03
Yujie Yu , Jianzhong Liu , Ruikun Wang +2 more

Mathematical models in the applied sciences

1998-12-01
A. C. Fowler
Part I. Introduction: 1. Mathematical modelling Part II. Methods: 2. Non-dimensionalisation 3. Asymptotics 4. Perturbation methods Part III. Classical Models: 5. Heat transfer 6. Viscous flow 7. Solid mechanics 8. 
 Part I. Introduction: 1. Mathematical modelling Part II. Methods: 2. Non-dimensionalisation 3. Asymptotics 4. Perturbation methods Part III. Classical Models: 5. Heat transfer 6. Viscous flow 7. Solid mechanics 8. Electromagnetism Part IV. Continuum Models: 9. Enzyme kinetics 10. The Belousov-Zhabotinskii reaction 11. Spruce budworm infestations 12. Chemical reactors 13. Groundwater flow 14. Convection in a porous medium 15. River flow 16. One-dimensional two-phase flow Part V. Advanced Models: 17. Alloy solidification 18. Ice sheet dynamics 19. Chemosensory respiratory control 20. Frost heave in freezing soils References.

The effect of coal properties on the viscosity of coal–water slurries

2002-09-01
GĂŒndĂŒz AteƟok , Feridun Boylu , Ayhan Ali Sirkeci +1 more

Comb‐like polymers. Structure and properties

1974-01-01
N.A. Platé , Valery P. Shibaev

Solvent extraction process development and on-site trial-plant for phenol removal from industrial coal-gasification wastewater

2006-01-20
Chun Yang , Yu Qian , Li‐Zhi Zhang +1 more

A Theory of Differential Thermal Analysis and New Methods of Measurement and Interpretation

1955-08-01
S. L. Boersma
A new‐type nickel‐block sample holder for use in differential thermal analysis is described. A simple machine to aid in the interpretation of complex curves is suggested. A new‐type nickel‐block sample holder for use in differential thermal analysis is described. A simple machine to aid in the interpretation of complex curves is suggested.

Occurrence of the Release Reaction during Preparation and Storage of Platelet Concentrates

1981-09-01
Edward L. Snyder , A. Hezzey , Alfed J. Katz +1 more
To determine the degree of damage occurring during preparation and storage of platelet concentrates, the percent release of B-thromboglobulin (BTG) and percent leakage of the cytosolic protein lactic dehydrogenase was 
 To determine the degree of damage occurring during preparation and storage of platelet concentrates, the percent release of B-thromboglobulin (BTG) and percent leakage of the cytosolic protein lactic dehydrogenase was determined sequentially from phlebotomy to the end of storage for 72 h at 20-24 degrees C. The effect of storage temperature, pH, and radiation was also evaluated. The results showed that during preparation of platelet concentrate a large degree of release was found after resuspension of the platelet button formed after the high-speed centrifugation. During storage the percent BTG release increased from 18.1 to 40.2% (p less than 0.05). The percent release seen during storage at 4 degrees C (72 h) was 19.2%, while that seen for platelets subjected to temperature cycling at 4-37 degrees C was 24.9%. Both of these values were significantly less (p less than 0.05) than that seen for concentrates stored at room temperature. A negative correlation between pH and BTG release was found (r = -0.64). Irradiation to 10,000 rad did not induce the release reaction or lactic dehydrogenase leakage. We conclude that the degree of in vitro platelet release is dependent on the preparative manipulations, and gentler protocols for preparation and storage of platelets should be investigated.

Combustion turbine dynamic model validation from tests

1993-01-01
L. N. Hannett , Alimul Haque Khan
Studies have been conducted on the Alaskan Railbelt System to examine the hydrothermal power system response after the hydroelectric power units at Bradley Lake are installed. The models and data 
 Studies have been conducted on the Alaskan Railbelt System to examine the hydrothermal power system response after the hydroelectric power units at Bradley Lake are installed. The models and data for the generating units for the initial studies were not complete. Typical models were used, but their response appeared to be faster than judged by operating experience. A testing program was felt to be necessary so that accurate models could be obtained for the dynamic simulation studies. The testing method used for the combustion turbine governors, the models derived from tests, and comparison of those models with typical models are discussed. Simulation results revealed that the typical models were more optimistic.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>

Influence of Slurry Parameters on the Characteristics of Spray‐Dried Granules

1999-07-01
William J. Walker , James S. Reed , Surendra Kumar Verma
A systematic study has been performed to determine how the characteristics of granules prepared by spray drying aqueous alumina slurries are influenced by processing parameters: binder type (PEG Compound 20M 
 A systematic study has been performed to determine how the characteristics of granules prepared by spray drying aqueous alumina slurries are influenced by processing parameters: binder type (PEG Compound 20M or PEG‐8000), solids loading (30 or 40 vol%), ammonium polyacrylate deflocculant level (0.35‐1.00 wt%), and spray‐dryer type. Correlations between slurry rheology and granule characteristics have been made, and a model for granule formation is presented. The packing density of the primary particles within the granules is lower for slurries with higher yield stress and is dependent on the slurry solids loading. Granules prepared using 0.35 wt% deflocculant (0.14 mg/m 2 ), which correspond to high slurry yield stress, are of solid morphology, whereas higher deflocculant levels result in hollow granules that contain a single large open pore or crater. The degree to which particles are able to rearrange during drying influences the final granule density and is determined by the strength of the floc structure, as indicated by the slurry yield stress. When the yield stress is low, a crater may form from the inward collapse of the surface of a forming granule when the particle packing density in a droplet continues to increase after the droplet size becomes fixed by the formation of a rigid shell, leaving an internal void with internal pressure lower than that of the surrounding atmosphere.

Preparation and Storage of Platelet Concentrates: II. STORAGE VARIABLES INFLUENCING PLATELET VIABILITY AND FUNCTION

1976-11-01
Sherrill J. Slichter , Laurence A. Harker
S ummary . Factors affecting the viability and function of stored platelet concentrates have been investigated in a blood component programme. It was found that platelets could be maintained for 
 S ummary . Factors affecting the viability and function of stored platelet concentrates have been investigated in a blood component programme. It was found that platelets could be maintained for up to 72 h without bacterial contamination under the following conditions: (1) surgical skin preparation at venipuncture site; (2) blood collection in CPD or ACD anticoagulant in a closed bag system; (3) centrifugation of PRP at 3000 g for 20 min; (4) storage in Fenwal PL‐146, Cutter CL‐2383, or McGaw plastic bags; (5) resuspension of the platelet pellet in 70 ml residual plasma; (6) storage at 22± 2°; and (7) constant gentle mixing throughout storage. Platelet viability as determined by recovery and survival is largely maintained, as is platelet function measured by template bleeding time. Both viability and function of concentrated platelets stored at 4° are severely compromised.

Full-scale application of the SHARON process for treatment of rejection water of digested sludge dewatering

2001-06-01
Jan‐Willem Mulder , Mark C.M. van Loosdrecht , C. Hellinga +1 more
At the Rotterdam Dokhaven WWTP the first full-scale application of the SHARON process has been constructed. In the SHARON process, rejection water from dewatering of digested sludge is treated for 
 At the Rotterdam Dokhaven WWTP the first full-scale application of the SHARON process has been constructed. In the SHARON process, rejection water from dewatering of digested sludge is treated for N-removal. It concerns a highly active process operating without sludge retention. The single tank reactor is intermittently aerated. Due to differences in growth rate nitrite oxidisers are washed out of the system while ammonia oxidisers can be maintained, resulting in N-removal over nitrite. The SHARON process has been selected after comparison with several other techniques. The feed of the SHARON tank is concentrated, with ammonia concentrations over 1 g N/l. The first results show that conversion rates of 90% are quite possible with N-removal mainly via the nitrite route. The process was shown to be stable. Due to the high inlet concentrations pH control is of great importance, preventing process inhibitions. The acidifying effect of nitrification can be compensated completely by CO2 stripping during aeration and by denitrification. Heat production by biological conversions appeared to be significant, due to the high inlet concentrations, and contributes to the optimal operating temperature of 30-40°C.

Physicochemical Properties of Oil-Based Nanofluids Containing Hybrid Structures of Silver Nanoparticles Supported on Silica

2011-02-04
Subelia Botha , Patrick Ndungu , Bernard Jan Bladergroen
The structural, rheological, thermal, and dielectric properties of transformer oil-based nanofluids containing silica and silver supported on silica were investigated. Thermal conductivity was found to increase with silica concentration. The 
 The structural, rheological, thermal, and dielectric properties of transformer oil-based nanofluids containing silica and silver supported on silica were investigated. Thermal conductivity was found to increase with silica concentration. The greatest enhancement was seen with silver nanoparticles supported on silica at very low weight percent of silica.

Advances in Polymer Science

1981-11-01

Relationship between enhanced dewaterability and structural properties of hydrothermal sludge after hydrothermal treatment of excess sludge

2017-01-21
Liping Wang , Aimin Li , Yuzhi Chang

Effects of hydrophilic groups of nonionic surfactants on the wettability of lignite surface: Molecular dynamics simulation and experimental study

2018-05-29
Jianying Guo , Lei Zhang , Shengyu Liu +1 more

Molecular dynamics simulation and experimental characterization of anionic surfactant: Influence on wettability of low-rank coal

2020-06-29
Zongqi Liu , Gang Zhou , Shuailong Li +3 more

Fluidized Bed Combustion

2009-04-23
Energy production and fluidized bed combustion technology development development of fluidized bed combustion boilers fundamental processes in fluidized bed combustion boiler furnaces hydrodynamics of gas-solid fluidization heat and mass transferin 
 Energy production and fluidized bed combustion technology development development of fluidized bed combustion boilers fundamental processes in fluidized bed combustion boiler furnaces hydrodynamics of gas-solid fluidization heat and mass transferin fluidized beds fundamental processes during coal combustion in fluidized beds fluidized bed combustion applications fluidized bed combustion in practice investigation of coal suitability for fluidized bed combustion harmful matter emissions fromfluidized bed combustion boilers.

Analytical Pyrolysis of Natural Organic Polymers

1998-01-01
Serban C. Moldoveanu
Part 1: An Introduction to Analytical Pyrolysis. 1. Introduction and Nomenclature. Pyrolysis as a chemical process. The scope of analytical pyrolysis. Analytical pyrolysis applied to natural organic polymers. 2. The 
 Part 1: An Introduction to Analytical Pyrolysis. 1. Introduction and Nomenclature. Pyrolysis as a chemical process. The scope of analytical pyrolysis. Analytical pyrolysis applied to natural organic polymers. 2. The Chemistry of the Pyrolytic Process. General remarks. Elimination reactions in pyrolysis. Rearrangements taking place in pyrolysis. Oxidations and reductions taking place in pyrolysis. Substitutions and additions taking place in pyrolysis. Typical polymer degradations during pyrolysis. Pyrolysis in the presence of additional reactants or with catalysts. 3. Physico-Chemical Aspects of the Pyrolytic Process. Thermodynamic factors in pyrolytic chemical reactions. Kinetic factors in pyrolytic chemical reactions. Models attempting to describe the kinetics of the pyrolytic processes of solid samples. Pyrolysis kinetics for uniform repetitive polymers. Pyrolytic processes compared with combustion. Pyrolysis process compared to ion fragmentation in mass spectrometry. Theoretical approaches for chemical pyrolytic reactions. 4. Instrumentation Used for Pyrolysis. The temperature control of the pyrolytic process. Curie point pyrolysers. Resistively heated filament pyrolysers. Furnace pyrolysers. Radiative heating (laser) pyrolysers. Other pyrolyser types. Comparison of analytical performances of different pyrolyser types. 5. Analytical Techniques Used with Pyrolysis. The selection of the analytical techniques and the transfer of the pyrolysate to the analytical instrument. Pyrolysis-gas chromatography (Py-GC). Mass spectrometers as detectors in pyrolysis-gas chromatography. Pyrolysis-mass spectrometric (Py-MS) techniques. Data interpretation in pyrolysis - mass spectrometry (Py-MS). Infrared spectroscopy (IR) used as a detecting technique for pyrolysis. Other analytical techniques in pyrolysis. Part 2: Analytical Pyrolysis of Organic Biopolymers. 6. Analytical pyrolysis of polyterpenes. Natural rubber. Vulcanized rubber. Other polyterpenes. 7. Analytical Pyrolysis of Polymeric Carbohydrates. Monosaccharides, polysaccharides and general aspects of their pyrolysis. Cellulose. Chemically modified celluloses. Amylose and amylopectin. Pectins. Gums and mucilages. Hemicelluloses and other plant polysaccharides. Algal polysaccharides. Microbial polysaccharides. Lipolysaccharides from the cell surface of bacteria. Fungal polysaccharides. Glycogen. Chitin. Proteoglycans. 8. Analytical Pyrolysis of Polymeric Materials with Lipid Moieties. Classification of complex lipids and analytical pyrolysis of simple lipids. Complex lipids. 9. Analytical Pyrolysis of Lignins. Lignin. Lignocellulosic materials. Chemically modified lignins. 10. Analytical Pyrolysis of Polymeric Tannins. Polymeric tannins. 11. Analytical Pyrolysis of Caramel Colors and of Maillard Browning Polymers. Pyrolysis of caramel colors. Sugar-ammonia and sugar-amines browning polymers. Sugar-amino acid browning polymers. 12. Analytical Pyrolysis of Proteins.

Grain boundary discontinuous precipitation reactions

1981-01-01
D. B. Williams , E. Butler

Cavitation erosion of materials

1986-01-01
A. Karimi , Juliette Martin

34th International Symposium on Combustion

2012-01-01
R. Lemaire , C. BRUHIER , H. . KOUICHI +2 more

Fundamentals of coal combustion : for clean and efficient use

1993-01-01
L.D. Smoot

Impact of Mineral Impurities in Solid Fuel Combustion

2002-01-01
Rajender Gupta , Terry Wall , Larry Baxter

Advances in the Science of Victorian Brown Coal

2004-01-01
Chun‐Zhu Li

Modeling Engine Spray and Combustion Processes

2003-01-01
Gunnar Stiesch

Influence of temperature conditions of hydrocleaning process on fuel oil quality

2025-06-24
Ekaterina Sergeevna Akishina , Sergey Aleksandrovich Zhelnov , Dmitry Vyacheslavovich Kozirev +1 more | Oil and gas technologies and environmental safety
Hydrogenation processes of oil residue refining are widely studied by Russian and foreign scientific groups, but so far they have practically not been implemented at domestic refineries. Due to the 
 Hydrogenation processes of oil residue refining are widely studied by Russian and foreign scientific groups, but so far they have practically not been implemented at domestic refineries. Due to the increased requirements for the quality of petroleum products, including fuel oil, as well as an increase in the proportion of heavy fractions, there is an urgent issue of upgrading and increasing secondary processes for refining residual raw materials and increasing the proportion of light fractions. One of the relevant processes is the catalytic hydrotreating of fuel oil. There are many scientific approaches to studying the hydrotreating process, such as modification of catalysts, improvement of related process equipment and implementation schemes, optimization of operating parameters, as well as automation and environmental safety issues. Also, an equally important part of the research is the preservation of the commercial appearance of fuel oil after the hydrogenation process. The study of optimal modes of hydrogenation processes of residual raw materials is necessary for quality control of the products. Optimization of the process of hydrodesulfurization of fuel oil in the future should lead to the production of products with better characteristics, such as low pour point, lower viscosity and reduced coking capacity, which will make the fuel more suitable for use in various industries. The paper presents the results of tests of fuel oil for basic qualitative indicators, such as pour point, density, coking ability and kinematic viscosity after hydrotreating with varying process temperatures from 340-360 °C. The research was carried out on two catalysts TK-743 from Haldor Topsoe and HR-1246 Impulse, which are designed for hydrotreating residual fractions. Based on the results obtained, it can be seen that the temperatures used in the hydrotreating process not only do not worsen the fuel oil, but also have a positive effect on its quality.

Analytical method for determining the temperature dependence of the thermal conductivity coefficient

2025-06-22
Ya.P. Saliy , Б.ĐĄ. Đ”Đ·ŃƒĐœĐŽĐ·Đ° | Physics and Chemistry of Solid State
The paper developed an analytical method for determining the temperature dependence of the thermal conductivity coefficient, which is based on the approximation of the temperature field obtained using an infrared 
 The paper developed an analytical method for determining the temperature dependence of the thermal conductivity coefficient, which is based on the approximation of the temperature field obtained using an infrared thermal imaging camera by the solution of the inhomogeneous stationary equation of thermal conductivity. From the obtained experimental dependences, it is shown that the proposed method based on the stationary heat flux can be used to determine the temperature dependence of the thermal conductivity coefficient for solids: metals, multicomponent alloys, semiconductors and dielectrics. The temperature dependences of the thermal conductivity of test samples of fluoroplastic and steel were obtained. According to these experimental results, the thermal conductivity of fluoroplastic increases, and the thermal conductivity of steel decreases with increasing temperature.

Enhancing the flowability of woody biomass slurries in wet biorefineries

2025-06-21
Sampath Gunukula , Glenn Matamoros , Ehsan Ullah Sardar +2 more | Biomass and Bioenergy

Modeling of Turbulent Non-Isothermal Flow in a Heating Network Pipe

2025-06-18
U. K. Zhapbasbayev , Daniyar Bossinov , M.A. Pahomov +1 more | Bulletin of the Karaganda University Physics Series
The article presents a mathematical model of turbulent non-isothermal flow of viscoplastic fluid in a pipewith a sudden expansion of the heat network. Heat exchange of non-isothermal flow of viscoplastic 
 The article presents a mathematical model of turbulent non-isothermal flow of viscoplastic fluid in a pipewith a sudden expansion of the heat network. Heat exchange of non-isothermal flow of viscoplastic fluid withcold environment leads to an increase in its viscosity and yield strength. Shvedov-Bingham rheological modelrepresents the viscoplastic state of fluid. The Reynolds Stress Model (RSM) turbulence model describes theproperties of anisotropy of the velocity components of pulsating motion in a pipe with a sudden expansion. Inaddition, the ability to predict turbulence anisotropy of the RSM model is used to construct a linear model ofturbulent viscosity. Calculation data are obtained for different values of Reynolds and Bingham numbers. Thecalculation results show that with an increase in the Bingham number, the circulation zone decreases behindthe section of the sudden expansion of the pipe. The results of the comparison of the radial profiles of thenormalized axial mean and fluctuation velocity with the experimental data along the pipe with sudden expansionare given. The results show the anisotropic property of the axial and radial profiles of the velocity of fluctuationmovement, which are in agreement with the data of the DNS (Direct Numerical Simulation) model.

Cake Moisture Estimation Based on Image Analysis and Regression Model for Controlling the Compression Time of Filter Press in Sludge Dewatering

2025-06-17
Poltak Sandro Rumahorbo , Nobuhiro Yazawa , Hiroki Ito +6 more | Processes
This study proposes practical methods for estimating the moisture content of sludge, represented by the cake moisture, in the filter press dewatering process. Because the cake moisture and filtrate volume 
 This study proposes practical methods for estimating the moisture content of sludge, represented by the cake moisture, in the filter press dewatering process. Because the cake moisture and filtrate volume are difficult to measure directly, the proposed approaches utilize indirectly measurable data, including drain outlet images and the differential pressure during the compression phase. By analyzing the correlations between these parameters and the cake moisture, estimation models were developed using mathematical approximations. In the image-based approach, image processing techniques were applied to isolate the dewatered region, and the relationship between the pixel count and actual filtrate volume was analyzed to estimate the cake moisture based on the calculated filtrate volume per minute. In the pressure-based approach, two models were proposed: one that directly estimates the cake moisture from the differential pressure, and another that models the relationship among the differential pressure, filtrate volume, and cake moisture. Unlike complex machine learning techniques, the proposed methods employ simple and interpretable mathematical functions, offering both practicality and reliability. Validation using real-world operational data confirmed the accuracy and effectiveness of the proposed approaches.

The use of bottom and a mixture of bottom and fly ash from wood-sunflower biomass combustion in concrete production

2025-06-17
Jakub Jura , MaƂgorzata Ulewicz | Archives of Civil Engineering
As part of the research, concrete mixes containing the addition of bottom ash as well as bottom and fly ash mixtures from the combustion of biomass only were made. The 
 As part of the research, concrete mixes containing the addition of bottom ash as well as bottom and fly ash mixtures from the combustion of biomass only were made. The ashes were obtained from the combustion of 80% of wood and 20% of sunflower in a fluidized bed boiler. In the study, the elemental composition of ashes was determined by testing with an XRF X-ray spectrometer. Ashes in the amount of 10, 20 and 30% of the cement mass were used as a substitute for sand for testing concrete samples. During the preparation of concrete mixes, tests of consistency and air content in the mixes were carried out. Concrete samples were tested in terms of e.g. compressive strength, water absorption or frost resistance. The compressive strength of the samples with the addition of bottom ash was lower than the strength of the control samples. The use of a mixture of ashes allowed to improve this property and each of the samples obtained a higher compressive strength than samples without the addition of ash. The addition of ashes significantly improves the frost resistance of concrete, i.e. reduces the decrease in the compressive strength of concrete after frost resistance tests. The absorbability of the samples, regardless of the amount and type of added ash, changed slightly in relation to the control samples.

Influence of terminal group structure in hydrophilic long side chains of polycarboxylate dispersants on the properties of coal water slurry: experimental and simulation insights

2025-06-17
Jianpeng Chen , Xiaoyu Wang , Tingao Jiang +5 more | International Journal of Coal Preparation and Utilization

Basic Characteristics of Two-Phase Flow of Air and Water at a Temperature of 60°C in a Horizontal Mini Channel

2025-06-15
Sudarja Sudarja , Sukamta Sukamta , Goma Ilham Putra Arsiwinarto +4 more | Journal of Advanced Research in Fluid Mechanics and Thermal Sciences
Gas-liquid two-phase flow in capillary channels is commonly found in microelectronic cooling systems, heat exchangers, and small-scale refrigeration systems. This study aims to bridge the gaps of the previous studies 
 Gas-liquid two-phase flow in capillary channels is commonly found in microelectronic cooling systems, heat exchangers, and small-scale refrigeration systems. This study aims to bridge the gaps of the previous studies by investigating two-phase flow in horizontal mini channels using air-water mixtures at a high temperature of 60°C. The fundamental characteristics of flow patterns, void fractions, and pressure gradients in horizontal mini channels with an inner diameter of 1.6 mm and a length of 130 mm were analyzed. Gas superficial velocities ranged from 0 to 66.3 m/s, while liquid superficial velocities ranged from 0.025 to 4.935 m/s. Flow patterns were visualized using high-speed imaging, while void fraction data were analyzed through digital image processing with MATLAB. Five primary flow patterns were identified: plug, bubbly, slug-annular, annular, and churn. The results revealed that the void fraction escalated with the rise in gas superficial velocity in plug and bubbly flow patterns. However, no consistent trend was observed in slug-annular, annular, and churn flow patterns due to the high slip ratio between gas and liquid velocities. Additionally, the pressure gradient rose with higher superficial velocities of both gas and liquid. These findings provide crucial insights into the dynamics of two-phase flow in mini channels, offering practical implications for optimizing thermal systems and enhancing the efficiency of small-scale heat exchangers.

Experimental Study on Slurry Ice Formation in Right Circular Cylinder and Its Empirical Model

2025-06-14
Sirachat Aruxvanit , Tanongkiat Kiatsiriroat , Thoranis Deethayat +1 more | Journal of Current Science and Technology
Slurry ice has the potential to serve as a secondary working fluid for cooling purposes or as a cold storage medium due to its high energy intensity. In the latter 
 Slurry ice has the potential to serve as a secondary working fluid for cooling purposes or as a cold storage medium due to its high energy intensity. In the latter application, it can overcome the drawbacks associated with using regular ice, such as ice bridging and insulation, thereby enhancing heat transfer between the exchanger surface and the surrounding medium. However, the solidification process depends on various factors, including the concentration of the freezing point depressant, the freezing point of the working medium, the size and shape of the storage medium, and its thermal properties. This study investigated the formation of slurry ice using water-ethanol and water-propylene glycol mixtures with different concentrations of freezing point depressants. The experiments were conducted in a freezer at temperatures around -15 and -20oC. The findings revealed that higher concentrations of freezing point depressants resulted in a faster growth rate of ice, however when the concentration exceeded 8 wt%, the opposite effect was observed. To better understand the process phenomena, a set of new empirical models was developed using polynomial curve fitting of related parameters in dimensionless forms to predict the amount of slurry ice formed over time. The results from the models showed good agreement with the experimental data across different concentrations of freezing point depressants and container sizes.

Influence of operational parameters on downdraft gasifier performance using municipal solid waste (MSW)-biomass blends

2025-06-14
Narsimhulu Sanke , Rupesh Kumar , Md. Aleem Pasha +2 more | Energy Sources Part A Recovery Utilization and Environmental Effects

Mechanisms of Biogas Production Under Synergistic Catalysis Between Coal and Various Minerals

2025-06-01
Daping Xia , Hang Lv , Kuo Jan +4 more | Journal of environmental chemical engineering

Thermal Decomposition of Pellets from a Mixture of Peat and Bark Waste

2025-06-01
A. P. Terekhin , Pavel Maryandyshev , Irina I. Golovanova +1 more | Lesnoy Zhurnal (Forestry Journal)
There are large peat deposits in the Arkhangelsk Region. According to the balance sheet data, there are 626 deposits, each of which has an area exceeding 10 ha. At the 
 There are large peat deposits in the Arkhangelsk Region. According to the balance sheet data, there are 626 deposits, each of which has an area exceeding 10 ha. At the same time, the Arkhangelsk Region faces the problem of efficient energy utilization of secondary energy resources, such as wood waste and bark, generated at timber industry enterprises. Thermal analysis of pellets from a mixture of peat (80 %) and bark waste from pulp and paper production (20 %) has been performed on a synchronous thermal analyzer in an argon and air environment in the temperature range of 30–700 °С. Peat has been collected in the Mezensky District of the Arkhangelsk Region, and samples of bark waste have been collected from the bark feed line to the E-75-3.9-440 DFT and KM75-40M fluidized bed boiler units installed at TPP-3 of Arkhangelsk Pulp and Paper Mill. The pellets have been obtained in a pellet-press. The elemental composition of pellets has been studied using a spectrometer. The main ash- and slag-forming elements in the samples are silicon, aluminum, calcium and iron. The thermal analysis of pellets has been carried out on a synchronous thermal analyzer in an argon and air medium with a flow rate of 20 cm3/min. To observe the drying and thermal transformations of pellets, the curves of the decrease in mass and speed of this process in the studied samples of fuel pellets have been used. It has been shown that the release of volatile substances has occurred at temperatures from 170 to 430 °C. The resulting pellets are high-calorie and low-ash biofuel. The results of the research can be applied for theoretical substantiation of the production of fuels with high combustion heat and mechanical strength in order to increase the role of local biomass in the energy sector of the Arkhangelsk Region.

Bioenergy Potential of Sea Buckthorn Branches: A Study on the Multicomponent Kinetics and Thermodynamics of Its Pyrolysis

2025-06-01
Jie Cui , Zhitong Yao , Huanxuan Li +7 more | Renewable Energy

Analysis of influencing factors on the properties of coal-to-direct liquefied diesel

2025-06-01
Zhenyu Qi , Linsheng Li , Xingbao Wang +2 more | Journal of Fuel Chemistry and Technology

Research on Fluid-Structure Interaction of Spent Fuel Storage and Transportation Basket

2025-06-01
Chen Wang , Jiaojiao Dong , Wei Qin | International Journal of Advanced Nuclear Reactor Design and Technology

Highly concentrated iron ore slurry flow through pipeline with and without chemical additive; part I: Experimental investigations and proposed model for the prediction of pressure drop

2025-06-01
Stuti Mishra , D. R. Kaushal | Journal of Hydrology and Hydromechanics
Abstract The present study comprises experimental and numerical analysis for flow of iron ore slurry (having particles with mean diameter, geometric standard deviation, and maximum static settled concentration of 55 
 Abstract The present study comprises experimental and numerical analysis for flow of iron ore slurry (having particles with mean diameter, geometric standard deviation, and maximum static settled concentration of 55 ”m, 2, and 75.2 w/w, respectively) flow through a 2-inch diameter pipeline in the flow velocity range of 1 to 3.5 m/s at high concentrations ranging from 60 to 72 % w/w without, and with chemical additive (Sodium-hexametaphosphate) at different dosages from 0.1 to 1.5% w/w of solids. The optimal dosage of chemical additive for maximum reduction in the rheological properties (absolute viscosity and yield stress) and pressure drop varies with solids concentration and increases from 0.8 to 1.2 % w/w of solids with an increase in solids concentration from 60 to 72% w/w. The critical deposition velocity also increases with an increase in solids concentration and additive dosages used in the present study in the range of 1 to 1.95 m/s. Modified Slatter’s method is proposed by replacing d 85 with a more accurate optimum particle diameter using the rheological and pilot plant pipe loop testing data collected in the present study. Based on comparison with experimental data, it is observed that the proposed modified Slatter’s method can predict the pressure drop with an error of ±15%.

Evaluation of the Surface Temperature of the Solid Phase Grains in Multiphase Flows

2025-06-01
D M Cichy , Bartosz Fikus , RadosƂaw TrębiƄski | Journal of Physics Conference Series
Abstract Multiphase flows are phenomena in which different phases of matter, such as liquid, gas and solid, occur simultaneously. One of the challenges associated with multiphase flows is the accurate 
 Abstract Multiphase flows are phenomena in which different phases of matter, such as liquid, gas and solid, occur simultaneously. One of the challenges associated with multiphase flows is the accurate prediction of the surface temperature of the solid phase grains. This temperature is critical for the chemical reactions and thermal processes that occur in such systems. For flows with a large number of particles, determining the temperature of a single grain would be numerically inefficient. Therefore, this paper attempts to derive an algebraic expression for the surface temperature of a solid phase in multiphase flows. Quadratic and cubic profiles were used to approximate the temperature distribution function within the grain. To verify the derived equations, test cases of heating of grains with spherical, cylindrical and planar symmetry were formulated and solved numerically with 1D and 3D models.

Numerical investigation of flue gas recirculation impacts on coal combustion and raw meal decomposition in an oxy-fuel cement precalciner

2025-06-01
Quanliang Li , Feng He , Shuxia Mei +3 more | Energy

Bio-chemical composition for inhibition of spontaneous combustion of sewage sludge and reduction of odor

2025-05-31
Qhwang-Hee Rhee , Hyun Tae Jang | Journal of the Korea Academia-Industrial cooperation Society

Investigating Polymeric Elastomers for Cavitation and Erosion Resistance

2025-05-29
Allen Skaja , Christine N. Henderson | Materials performance
Cavitation and erosion damage are observed on water infrastructure. Mitigating degradation on mild steel traditionally includes stainless-steel weld overlays, which create a galvanic corrosion cell in immersion conditions. This can 
 Cavitation and erosion damage are observed on water infrastructure. Mitigating degradation on mild steel traditionally includes stainless-steel weld overlays, which create a galvanic corrosion cell in immersion conditions. This can cause delamination of the stainless steel and subsequent loss of cavitation or erosion protection. Elastomeric coatings could be combined with stainless steel weld overlays to eliminate the galvanic corrosion cell, thus protecting and extending the service life of the repairs. This article finds that elastomers provide better cavitation and erosion resistance than ceramic-filled epoxies.

Study on the separation and quality improvement of &lt;6 mm low rank high sulfur lignite by vibration airflow dry separation bed

2025-05-28
H. Susan Zhou , Bochao Li , Xiaodong Yu +2 more | Separation Science and Technology

Effect of adding water to liquid fuel on the kinetic characteristics of its ignition

2025-05-27
Д.В. ĐĐœŃ‚ĐŸĐœĐŸĐČ , V.V. Dorokhov , V.M. Ezhov +2 more

Solid–Liquid Flow Analysis of Francis‐99 Turbine Runner: Effects of Sediment Concentration

2025-05-26
Kang Xu , Pan Xiang , Ziyao Zhou +4 more
ABSTRACT This study examines the behavior of solid–liquid two‐phase flow within the runner of the Francis‐99 turbine. Numerical simulations were carried out by Ansys Fluent software using the Mixture multiphase 
 ABSTRACT This study examines the behavior of solid–liquid two‐phase flow within the runner of the Francis‐99 turbine. Numerical simulations were carried out by Ansys Fluent software using the Mixture multiphase flow model along with the Realizable k‐Δ turbulence model to analyze the solid–liquid two‐phase flow in the turbine runner. The sediment distribution on the turbine runner surface was evaluated for different sediment concentrations (SC = 500, 1500, 2500, 5000, 8000, and 11,500 ppm). The results indicate that sediment particles within the runner primarily adhere to the surfaces of the runner blades, displaying a uniform distribution. With increasing sediment concentration, the sediment volume fraction on the turbine blade surface rises significantly. The sediment distribution on both long and short blades exhibits similarity, with peak concentration observed at the trailing edge and mid‐sections of the blades. Additionally, the sediment volume fraction is greater on the pressure side of the blades than on the suction side. This study aims to expand the research on multiphase flow characteristics of the Francis‐99 turbine.

Utilization of water/waste engine oil emulsion for the preparation of chemical additives-free coal slurry

2025-05-24
Keke Zhao , Jun Chen , May‐Hua Chang +5 more

Review: Axial Motion of Material in Rotary Kilns

2025-05-22
E R Fedorova , Vladimir Morgunov , Kirill Lobko +1 more
The article examines the parameters of axial motion of bulk material in rotary kilns, including bed height, axial velocity, and mean residence time. The review includes summary tables of experiments 
 The article examines the parameters of axial motion of bulk material in rotary kilns, including bed height, axial velocity, and mean residence time. The review includes summary tables of experiments from the scientific literature, detailing the conditions and ranges of operating parameter variations. Mathematical models from the literature are presented for each of the parameters discussed. The materials of the article cover studies from 1927 to 2025, including analysis of numerous works that were not published in international sources. Based on the review, the necessity of studying the impact of coating formation on the axial motion parameters is highlighted, along with the need for experiments on real facilities and pilot plants.

On modelling and simulation of auto-ignition in particle-laden biomass flows

2025-05-21
Uldis Strautins , Maksims Marinaki | Engineering for Rural Development
This study focuses on the safety-critical problem of auto-ignition in particle-laden flows, where biomass particles enter a computational domain, form deposition layers (“cake”), and are susceptible to ignition due to 
 This study focuses on the safety-critical problem of auto-ignition in particle-laden flows, where biomass particles enter a computational domain, form deposition layers (“cake”), and are susceptible to ignition due to thermal and chemical interactions. Such scenarios are particularly relevant in storage silos, biomass processing plants, and industrial systems, where ignition can lead to deflagration, causing safety hazards and operational disruptions. In previous works we have used the finite volume techniques implemented in the Octave/Matlab environment and have simulated the temporal evolution of solute distribution and solvent velocity in two and three dimensions. The modified equations for a system with moving particles in Lagrangian coordinates have been solved. As a result, we have observed the behaviour of different portions of particles and the appearance of certain layer-type patterns – something of a wide interest in different applications. The modular framework we have created can accommodate custom laws, offering versatility across industrial contexts. To address the current issue, we discuss the applications of particle motion equations with combustion models derived from the Navier-Stokes framework, accounting for heat transfer, species transport, and chemical reactions. The ignition mechanism is characterized by coupling the thermal energy equation with pyrolysis kinetics to simulate volatile release and heat feedback in the system. Critical parameters, such as layer thickness, oxygen concentration, heating rates, and ambient conditions, can be systematically varied to identify ignition thresholds. These findings have a potential of a framework for engineers to design safer biomass storage and processing environments by understanding and controlling the conditions that lead to ignition. This work serves as a foundation for further research on combustion-driven safety in industrial particle-laden systems.

Nonsilting transport characteristics of coal slurry in a deep underground fluidization conveying pipeline under the action of a guide vane swirler

2025-05-21
Jiusheng Bao , Shaodi Zhao , Yan Hong Yin +3 more
Abstract The depth of coal mining is expected to increase continuously owing to the exhaustion of shallow coal resources. However, with the continuous increase in mining depth, transportation and lifting 
 Abstract The depth of coal mining is expected to increase continuously owing to the exhaustion of shallow coal resources. However, with the continuous increase in mining depth, transportation and lifting difficulties in deep mines have significantly increased, and traditional wire rope lifting methods can no longer meet the needs of deep transportation. Based on the principle of pipeline hydraulic lifting, a deep coal fluidization pipeline lifting system has been proposed. To address the problem of particle settlement in the horizontal connection section of large particles, a scheme involving the installation of guide vane‐type swirlers in the conveying pipeline is proposed. First, the impact of the guide vane parameters on the liquid flow field and solid particles within the pipeline was studied, and a mathematical model of the characteristic parameters of the swirler was established. Suitable guide vane parameters for the swirler were determined by considering factors such as the alleviation of particle settling, energy utilization efficiency, and the structural strength of the swirler. On this basis, the movement patterns of particles of different sizes in pipelines with and without swirlers were investigated. The study found that under conditions of high velocity and large particle size, the swirler was more effective in improving the slurry flow state within the pipeline. Subsequently, a quantitative method for determining the slurry flow state in the spiral flow pipeline was established, using the particle proportion within the pipeline section as an evaluation index, while considering flow velocity and particle size. Finally, the bench test results show that adding a swirler can reduce the critical nonsilting velocity and resistance loss of the slurry conveying pipeline by 9% and 42.9%, respectively, and we elucidate the internal mechanisms behind these reductions.

Mechanical properties of ecological composite material with oil shale ash particles

2025-05-21
Ilgar Jafarli , Armands Grickus , Igors Tipāns +1 more | Engineering for Rural Development
The need for “ecological” and “green” materials is increasing because of the strong demand to reduce the speed of climate change and decrease carbon footprint of human activities in nature. 
 The need for “ecological” and “green” materials is increasing because of the strong demand to reduce the speed of climate change and decrease carbon footprint of human activities in nature. In the cement production process high amount of CO2 is obtained as by-product. In the present research cement in a concrete mix is partially replaced by oil shale ash (OSA). OSA is a by-product itself, so utilisation of it also positively affects the environment. OSA particles have different size, and fabricating of such “ecological” concrete composite material with the concrete matrix reinforced by OSA particles is obtained. Similar situation is obtained during reinforcement of epoxy resin by OSA particles. Obtaining particle reinforced composite, the problem of precise prediction of the composite material averaged elastic properties appeared. The particles have different size, shape and are chaotically distributed in the concrete volume. Elastic properties averaging methods – theoretical models, including the rule of mixtures Voigt method, rule of mixtures Reuss method and Halpin–Tsai method, were used. Results were compared with experimental data. For that, samples (prisms 40x10x10cm) of concretes having cement replaced by 0%, 10%, 15%, 20%, 25%, 30%, 35% of OSA were fabricated and tested by the four-point bending test. The results that were obtained showed that the rule of mixtures Voigt and the rule of mixtures Reuss method as well as Halpin-Tsai methods generally slightly underestimate the value of elastic modulus for concrete-OSA, whereas the Mori-Tanaka and Halpin-Tsai methods provided closer predictions.

Rheological and stability behavior of coal–water slurry: the impact of pH with dual-impeller configurations

2025-05-20
Purushottam Karthik J , Tara Sasanka C , A. Muddu +2 more

Encapsulation techniques of sludge generated from wastewater treatment

2025-05-20
Devvrat Dhiman , Avneesh Anshul

Study on the mechanism of hydrothermal pretreatment enhancing the flotation of coal gasification fine slag

2025-05-17
Yalu Sun , Panpan Fan , Jinjin Yang +4 more

Optimization of Bottom Ash Water Slurry Flow Characteristics by using Commercial Additive

2025-05-16
Kaushal Kumar , Puja Acharya , Subhav Singh +4 more
In this study, the rheological feature of bottom ash-water slurry was investigated by using NaCl as an additive. The additive was added into the bottom ash suspension with proportions of 
 In this study, the rheological feature of bottom ash-water slurry was investigated by using NaCl as an additive. The additive was added into the bottom ash suspension with proportions of 0.2, 0.4, and 0.6% (by weight). The range of solid concentration in the suspension varied from 10 to 60 % (by weight). When compared to the normal condition or without additive, the addition of NaCl results in a very obvious reduction in the apparent viscosity of the solution. The addition of 0.4% additive shows good agreement with the reduction of energy consumption as compared to the rest of the range of velocities. Because of the reduction in energy consumption, the required pump power decreased up to a remarkable limit of approximately 20%. Sensitivity analysis demonstrates that increasing NaCl concentration reduces apparent viscosity, pressure drop, and specific energy consumption, leading to improved flow efficiency. According to the findings of the investigation, the suspension of bottom ash slurry described in the above manner has the potential to be transported in a slurry pipeline using the least amount of energy.

JUSTIFICATION OF THE MECHANISM OF THE FIRE EXTINGUISHING ACTION OF THE POWDER BASED ON AN ANALYSIS OF ITS FRACTIONAL COMPOSITION IN A NON-STATIONARY GAS-POWDER FLOW

2025-05-16
Dmitriy Kozhevin
Based on experimental data on the analysis of the distribution of particles in a non-stationary gas-powder flow by fractional composition, maps of the particle size distribution in the cloud were 
 Based on experimental data on the analysis of the distribution of particles in a non-stationary gas-powder flow by fractional composition, maps of the particle size distribution in the cloud were obtained. The analogy method is used to substantiate the similarity of the configuration of powder particles in the cloud layer with the mesh. The thermophysical characteristics of the powder layer and mesh were determined; the calculation showed that the power of heat removal by the front of the powder cloud corresponds to the power of heat removal by a metal mesh with a cell size of 1 mm. It has been experimentally confirmed that the contact time of a grid with a mesh size of 1 mm or less with the flame front does not affect the extinguishing effect; therefore, the priority mechanism for stopping combustion of powder is cooling the combustion zone in narrow channels.