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Artykuły w czasopismach na temat "Fly Ash Cenosphere"
1
Manоcha, L. M., K. A. Ram i S. M. Manocha. "Separation of Cenospheres from Fly Ashes by Floatation Method". Eurasian Chemico-Technological Journal 13, nr 1-2 (21.12.2010): 89. http://dx.doi.org/10.18321/ectj72.
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Fly-ashes are non-combustible mineral residues which are produced from coal in thermal power plants. Four different types of fly ashes were collected from different power station in Gujarat. Characterization through SEM shows that fly ash contains cenosphere i.e. gas bubble containing ceramic particle independent of their bulk density. Floatation technique was used for the separation of cenosphere from fly ash. Two solvents with extremely different densities were used for the separation of cenospheres. All methods gave approximately yield of less than 1 % cenosphere in fly ash. Color of cenospheres varied from gray to almost white and the value of density range from 0.4 – 0.8 g/cc. Further, chemical composition analysis revealed that cenospheres do not contain any high concentration of hazardous elements.
2
Liu, Zhongwei, Kang Zhao, Yufei Tang i Chi Hu. "Preparation of a Cenosphere Curing Agent and Its Application to Foam Concrete". Advances in Materials Science and Engineering 2019 (3.03.2019): 1–9. http://dx.doi.org/10.1155/2019/7523492.
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Cenospheres are hollow and spherical particles extracted from fly ash. Controllable separation of cenosphere particles with different densities and sizes can be realized by controlling the density of a flotation solution of cenospheres. In this paper, cenospheres were corroded by hydrofluoric acid to produce perforated pores on their shell surfaces. Then, the cenospheres were mixed with water to prepare the cenosphere curing agent. Foam concrete was prepared using ordinary Portland cement (42.5 R), vegetable protein foaming agent, fly ash, cenospheres, and the cenosphere curing agent as raw materials. The water absorption rate of the cenosphere curing agent was 156.0 wt.%, and 85% of the loaded water was released at a relative humidity of 97.4%, which met the microenvironment requirements of foam concrete. Addition of the cenosphere curing agent during foam concrete preparation has the following positive functions for foam concrete: inhibiting autogenous shrinkage, promoting the hydration degree, improving the state of the interfacial transition zone between cenospheres and the hardened cement paste, reducing the number of connected pores, relieving the stress concentration on the pore walls, and enhancing the compression strength of the foam concrete.
3
Yoriya, Sorachon, i Phattarathicha Tepsri. "Separation Process and Microstructure-Chemical Composition Relationship of Cenospheres from Lignite Fly Ash Produced from Coal-Fired Power Plant in Thailand". Applied Sciences 10, nr 16 (10.08.2020): 5512. http://dx.doi.org/10.3390/app10165512.
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The cenosphere is one becoming a focus of the power plant in terms of value addition and ash management. This study presents a systematic investigation and characterization of physical properties, morphological structures, and chemical composition of cenospheres separated from fly ash produced from the Mae Moh coal-fired power plant, Thailand. To our knowledge, this is the first report on cenospheres separation from Mae Moh class C fly ash, with high calcium content ~24 wt.%, by adopting the traditional wet separation method (using water as the medium) to separate the lightweight cenospheres. Various effects of process parameters (fly ash-to-water ratio, stirring method, ultrasonication, and size classification) were designed to examine the cenosphere recovery yield in comparison. The result has revealed the limit of physical stirring-settling effect associated with the cenospheres content by nature governing the percent recovery. The bulk cenospheres were subject to size sieving into different sized fractions, with the structure-chemical composition relationship established for more insight. The particle diameter/shell thickness ratio revealed its significant correlation with the aluminosilicate glass composition, with the relating cenosphere shell structures (single-ring and porous) mapped to compare for a better elucidation of their structure-property relationship. The phase composition was also studied.
4
Wrona, Jan, Witold Żukowski, Dariusz Bradło i Piotr Czupryński. "Recovery of Cenospheres and Fine Fraction from Coal Fly Ash by a Novel Dry Separation Method". Energies 13, nr 14 (11.07.2020): 3576. http://dx.doi.org/10.3390/en13143576.
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Aluminosilicate microspheres are a valuable fraction of coal fly ash with diverse applications due to their low density. Currently, there is no efficient and ecologically rational method of cenosphere recovery from fly ash. A combination of dry methods for the recovery of both fine ash particles and aluminosilicate microspheres from coal fly ash is presented. It is comprised of fluidised bed separation followed by screening and pneumatic separation in a free-fall air chamber. Fluidised bed separation was assisted by a mechanical activator to prevent agglomeration. This step reduced the portion of material that required further treatment by 52–55 wt.%, with the recovery of microspheres exceeding 97%. Then, the concentrates were individually subjected to pneumatic separation. The final separation product for the fly ash containing 0.64 wt.% cenospheres was a cenosphere concentrate that constituted about 17 wt.% of the initial fly ash. The recovery of cenospheres was around 81%. Usage of a combination of dry methods allowed for maintaining almost 83 wt.% of the raw material in its dry form. Furthermore, the produced fly ash grain fractions could be used for different industrial purposes.
5
Yoriya, Sorachon, i Phattarathicha Tepsri. "Crystal Growth on Cenospheres from High-Calcium Fly Ash". Crystals 11, nr 8 (7.08.2021): 919. http://dx.doi.org/10.3390/cryst11080919.
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This work presents a study of cenosphere separation from lignite high-calcium (~24 wt.%) fly ash by centrifugal method; this is the first report for Mae Moh, Thailand, fly ash with this high calcium content using this technique. The effect of centrifugal parameters on cenosphere yield and properties were investigated. Those properties include physical properties, morphology, chemical composition, and mineral phases. The recovery yields are in the range of 0.34–0.64%, approximately one third of the yield obtained from the general gravity settling method. Density, particle size, and morphology of the collected cenospheres appeared to be independent of sequence of the applied speeds and times. Interrelation of chemical composition and mineral phases was established, with the focus on calcium carbonate formation on cenosphere surface and crystallite size study. The study has revealed the preferential formation of calcite–(104) peak is observed–by cenospheres, with stable growth behavior of crystallite sizes obtained from all the centrifugal conditions. The result was compared to that obtained from the sink-float method for a better insight. The influence and limitation of the centrifugal method, the varied parameters, and the relevant reaction pathways on crystal growth process in terms of important dissolving species (i.e., Ca2+ and CO32−) behavior in the ash suspension were discussed.
6
Soh, Wei Ming, Jully Tan, Jerry Y. Y. Heng i Christopher Cheeseman. "Production of Cenospheres from Coal Fly Ash through Vertical Thermal Flame (VTF) Process". Materials Science Forum 880 (listopad 2016): 7–10. http://dx.doi.org/10.4028/www.scientific.net/msf.880.7.
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Coal fly ash is a complex mixture of anthropogenic materials produced during the combustion of pulverised coal in coal fired power plants. They pose environmental concerns that lead to air and water pollution. Effort has been done to reduce the production of coal fly ash or to extract potentially valuable products from coal fly ash, such as cenospheres. Cenospheres are light, low density, thin-walled hollow ceramic microsphere with unique properties. Conventional cenosphere production methods involve the separation of cenospheres from coal fly ash. Due to its small quantities in fly ash (1 % wt.), separation process results in low production of cenospheres. In this work, an attempt by applying a vertical thermal flame (VTF) process is done to produce cenospheres from coal fly ash. Particle size of coal fly ash 63 to 90 μm and 90 to 126 μm are selected to undergo the VTF process. Effect of size of precursor, number of passes through the thermal process, density, morphology and particles size of generated spheres are evaluated. The results show that different sizes of coal fly ash and number of passes through the VTF process affect the morphology of obtained spheres and the overall real density. Further optimization of the VTF process design in terms of heat source and the feeding mechanism are required to increase the transformation of coal fly ash to cenospheres.
7
Asavavisithchai, Seksak, i Attanadol Prapajaraswong. "Effects of Different Types of Power Plant Ashes on Foamability and Structure of Al Foams". Advanced Materials Research 770 (wrzesień 2013): 10–13. http://dx.doi.org/10.4028/www.scientific.net/amr.770.10.
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Addition of power plant ash particles, classified as cenosphere and precipitator fly ashes, and bottom ash, to Al foams resulted in different foamabilities and foam structures. These distinctions arise from a difference in physical and chemical characteristics of ash particles. The cenosphere fly ash is hollow, whilst the precipitator fly ash is dense. The bottom ash is also dense with irregular shape. The major chemical constituents of these ashes are SiO2, CaO, Al2O3 and Fe2O3. It is found that the improvement in foam expansion and structure is obtained from the addition of precipitator fly ash or bottom ash particles. The addition of cenosphere fly ash, however, leads to a decrease in foamability and non-uniform foam structure.
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Suresha, Bheemappa, Shivaprakash Vidyashree i Harshavardhan Bettegowda. "Effect of Filler Materials on Abrasive Wear Performance of Glass/Epoxy Composites". Tribology in Industry 45, nr 1 (15.03.2023): 111–20. http://dx.doi.org/10.24874/ti.1386.10.22.01.
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When creating polymer-based composites, plain weave fabrics and micron-sized fillers offer bidirectional strength and reduced voids/inhomogeneity. In the present work, It was investigated how glass fabric reinforced epoxy composite (G-E) performed during three-body abrasive wear with and without ceramic fillers (SiO2, Al2O3, graphite, and fly ash cenospheres). In experiments, loads of 20 N and 40 N were applied at various abrading distances of 500 m, 1000 m, 1500 m, and 2000 m. According to the results of sand abrasive wear test, the specific wear rates of G-E based composites are sensitive to fibre and filler/matrix adhesion. Under all tribo-test settings, the SWR for all particulate G-E composites decreases in the following order: G-E > Gr/G-E > SiO2/G-E > Al2O3/G-E > fly ash cenosphere/G-E. Furthermore, the specific wear rate of the fly ash cenosphere filled G-E composites were found to be lower than the G-E and other filler materials filled G-E composites. There was 38.7% reduction in the specific wear rate at 40 N, 2000 m in fly ash cenosphere filled G-E composite. As per the evidence of scanning electron microscope images of worn-out surfaces, mechanisms such as ploughing, fibre breakage, fibre pull-out, fibre thinning, and a network of microcracks caused the wear in composites.
9
Yoriya, Sorachon, i Phattarathicha Tepsri. "Investigation of Metal and Trace Elements of Cenospheres from Lignite High-Calcium Fly Ash (Thailand)". Water 13, nr 20 (19.10.2021): 2935. http://dx.doi.org/10.3390/w13202935.
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High-calcium fly ashes contain a large content of small particles including cenospheres of chemical constituents known to be similar to fly ash and the parent coal. Coal fly ash contains metal and trace elements that may leach out during disposal or utilization. This work aimed to understand an overview of cenosphere characteristics relating to fly ash and leaching study. To our knowledge, this is the first report on metal and trace element leaching of cenospheres separated from high-calcium (28.9 wt.%) class C fly ash produced from the Mae Moh coal-fired thermal power plant in Thailand. In this study, the cenospheres were separated from fly ash by a wet separation process (sink-float method) using water as medium. Physical properties, morphology, chemical composition, the mineral phases of cenospheres and fly ash have been characterized. Extraction was carried out by acid digestion; the selected metal and trace elements in this study are Mg, Al, Zn, Pb, Cd, Cr, and Cu; the obtained environmentally available concentrations of cenospheres were analyzed in comparison to those of fly ash. The concentrations of Cu, Cr, Pb, and Cd elements of interest in the leachates obtained from the toxicity characteristic leaching procedure (TCLP) showed the tendency to decrease in that order. All the elements were found below the permissible limit values regarding Thailand soil quality standards. Association of the heavy metal trace elements in cenospheres and fly ash was discussed in in terms of physico-chemical-geochemistry correlating with the leaching concentrations.
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Yoon, Seyoon, i Inhwan Park. "Micropore Structures in Cenosphere-Containing Cementitious Materials Using Micro-CT". Advances in Materials Science and Engineering 2017 (2017): 1–10. http://dx.doi.org/10.1155/2017/3892683.
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Cenospheres have been recently applied to increase the volume of uniform micropores in hardened cementitious materials. Therefore, application of micro-CT to cenosphere-containing binders will help better understand the micropores formed by cenospheres in the hardened materials. Accordingly, the present study prepared Portland cement paste, alkali-activated fly ash/silica fume, and alkali-activated fly ash with 60% weight replacement by cenospheres and reconstructed their micropore structures using micro-CT. From the pore structure, individual micropores were extracted and analyzed using the principal moment ratios (I11/I33 and I22/I33). Based on the moment ratios, the representative pore shapes were determined in the different pore-volume ranges. Four-factor pore compliance contribution (4-factor PCC) model was then applied to predict the influences of the micropores on the elastic moduli of the micropore/matrix composites.
Rozprawy doktorskie na temat "Fly Ash Cenosphere"
1
Acar, Ilker. "Characterization And Utilization Potential Of Class F Fly Ashes". Phd thesis, METU, 2013. http://etd.lib.metu.edu.tr/upload/12615688/index.pdf.
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In this thesis, characterization of two class F fly ashes (FA) from Çatalagzi and Sugö
zü
thermal power plants were carried out and their utilization potentials in three different fields were examined. Characterization of sintered samples and determination of their utilization potentials in ceramic industry is the first research area in this thesis. For this purpose, the class F fly ash samples were first pressed into cylindrical specimen without the addition of any organic binders or inorganic additives, and then sintered to form ceramic materials. Effects of sintering temperature and time on sintering characteristics were investigated. In the experiments, the cylindrical specimens were first preheated to 300oC for 1 h to remove moisture and any other gases. The specimens were then fired at the temperatures of 1000oC, 1050oC, 1100oC and 1150oC for the sintering times of 0.5, 1.0, 1.5 and 2.0 hours. Heating rate of 10oC/min was kept constant throughout the experiments. Quality of sintered samples was evaluated in terms of ceramic specifications such as density, water absorption, porosity, shrinkage and splitting tensile strength. In addition, mineralogical and microstructural changes during sintering were determined with X-ray diffraction (XRD) and scanning electron microscopy (SEM) analyses. According to literature data, better microstructure, the highest density and strength with the lowest porosity, water absorption and shrinkage values are the indications of the optimum sintering conditions. Based on these specifications, Sugö
zü
fly ash gave better results compared to Ç
atalagzi fly ash, and the optimum conditions were achieved at the sintering temperature of 1150oC for the sintering time of 1.5 hours for both samples. Pozzolanic reactivity of the fly ashes and their utilization potentials in civil engineering applications were also examined in detail during this study. For this purpose, Ç
atalagzi (CFA) and Sugö
zü
(SFA) fly ashes were first subjected to a specific hydraulic classification process developed at CAER (University of Kentucky, Center for Applied Energy Research) to recover ultrafine fly ash particles. The overflow products with average particle sizes of 5.2 &mu
m for CFA and 4.4 &mu
m for SFA were separated from the respective as-received samples with average particle sizes of 39 &mu
m and 21 &mu
m. After the classification stage, the pozzolanic activities of these ultrafine fly ash fractions (UFA) and as-received samples were examined by preparing a number of mortar (mixture of Portland cement (PC), FA or UFA as partial cement replacement, sand and water) and paste (mixture of PC, FA or UFA as partial cement replacement and water) specimens. Control samples containing only PC were also prepared and tested through the experiments for the comparison of the results. In the mortar experiments, three different PC replacement ratios by FA and UFA (10%, 20% and 30%) were used to examine the effects of FA and UFA samples on the fresh and hardened mortar properties such as water requirement, compressive strength, drying shrinkage and water expansion. These mortar tests indicated that ultrafine fractions of Ç
atalagzi (CUFA) and Sugö
zü
(SUFA) fly ashes provided more than 10% reduction in water demand compared to the control sample for 30% PC replacement. The mortar cubes containing CUFA and SUFA samples exhibited also higher strength development rates after 14 days compared to the ones with as-received samples and PC only. At the end of the curing age of 112 days, both CUFA and SUFA provided more than 40% increase in compressive strength compared to the control sample for the PC replacement ratios higher than 20%. As a comparison, SUFA gave better results than CUFA in both water demand and compressive strength tests. The mortar bars prepared with the both FA and UFA samples exhibited very low shrinkage and expansion values. These values decreased generally with increasing PC replacement ratio especially after 14 days. In the paste experiments, thermogravimetric analyses (TGA) of the paste specimens prepared by using only with 20% PC replacement were carried out to determine pozzolanic reactivity of the samples. The difference between the remaining Ca(OH)2 (portlandite) contents in the paste specimens containing the fly ashes and the reference PC paste was used as a measure of pozzolanic reactivity. After 112 days, 68.56% and 62.68% Ca(OH)2 content of PC only pastes were obtained with the pastes containing CUFA and SUFA samples, respectively, corresponding to 11% and 13% more Ca(OH)2 consumptions in reference to the respective as-received samples. X-ray diffraction (XRD) analyses were also performed for comparison of main portlandite peak intensities in the paste specimens containing FA or UFA with those in the PC only paste during cement hydration. According to these XRD analyses, portlandite content in PC/UFA pastes decreased significantly after 14 days compared to the PC only paste. All of these tests and analyses showed that a highly reactive lower cost pozzolan with very fine particle size and higher surface area compared to regular fly ash pozzolans can be produced from both Ç
atalagzi and Sugö
zü
fly ashes using a relatively simple hydraulic classification technology. Cenosphere recovery potentials from Ç
atalagzi and Sugö
zü
fly ashes were also studied in this thesis. Determination of cenosphere content was done under optical microscope by particle counting on the basis of point and area. Based on the point-counting data, CFA and SFA samples originally contain 11.30% and 4.50% cenospheres, respectively. Variations of cenosphere contents in the fly ash samples were examined by using float-sink, screening and air classification tests. The results pointed out that cenosphere contents decreased with decreasing size and increasing density for both samples. According to the float-sink tests, Ç
atalagzi fly ash has much more floating products and more cenospheres than Sugö
zü
fly ash for the same density interval. Based on the air classification results, cenospheres were concentrated in the underflow products, and cenosphere contents increased with increasing air pressure and decreasing motor speed for both samples. The most efficient cenosphere separation technique among the examined methods was screening. Cenosphere contents of CFA and SFA increased to 21.65% and 11.83%, respectively by only using simple screening through 38 &mu
m.
2
Biju-Duval, Paul M. "A new porous material based on cenospheres". Thesis, Atlanta, Ga. : Georgia Institute of Technology, 2007. http://hdl.handle.net/1853/26523.
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Thesis (M. S.)--Civil and Environmental Engineering, Georgia Institute of Technology, 2008.Committee Chair: Dr. Mulalo Doyoyo; Committee Member: Dr. Arash Yavari; Committee Member: Dr. Kenneth M. Will. Part of the SMARTech Electronic Thesis and Dissertation Collection.
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Sopko, Marek. "Možnosti snížení surovinových nákladů při výrobě kordieritu". Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2013. http://www.nusl.cz/ntk/nusl-225884.
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The diploma thesis focuses on new possibilities to reduce raw materials costs in production of heat-resistant cordierite ceramics. Cordierite is very often used as furnace wagon lining and for production of blazing utilities for its high resistance against temperature changes. The thesis gives complete overview of cordierite material. It includes description of different production technologies for form-pieces preparation, raw materials for their production and their applications. The goal of performed laboratory measuring in an experimental part was to verify and prove a possibility of reducing raw-material costs in production of cordierite ceramics by using cheaper preferably secondary raw materials.
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Cacuro, Thiago Aguiar. "Caracterização de cinzas de queima de bagaço de cana-de-açúcar e prospecção de sua utilização como adsorvente". Universidade Federal de São Carlos, 2016. https://repositorio.ufscar.br/handle/ufscar/8941.
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
The ashes resulting from the burning of sugarcane bagasse is a heterogeneous material and has various applications as an adsorbent. To enhance and assist in prospecting new applications is critical to better understand the properties of the material. In this work, its morphological, spectroscopic and elemental characterization of the ashes of sugarcane bagasse from three different plants and two different harvests and the prospect of its use as an adsorbent. The particles of the ash were separated according to their density and in order to characterize, FTIR was used in the investigation of chemical groups present in the samples, additionally to the SEM and EDS elemental and morphological characterization of the particles present in the samples. Cenospheres, spherical particles present in ash, were identified as coreshell structure, where the core is a mixed metal oxide and the shell is a layer of silicon dioxide. The correlation between the ratio of the relative abundance between the carbonyl and hydroxyl groups and the mass distribution of the granulometric extracts were used as indirect measure of the level of oxidation of the samples. The ashes’ adsorption capacity showed affinity for the methylene blue dye with an adsorption capacity of 39 mg of dye per gram of ash used, in contrast to the low adsorption of potassium chromate solution, 1.2 mg per gram of ash.
As cinzas oriundas do processo de queima do bagaço de cana-de-açúcar são um material heterogêneo e com diversas aplicações, como a adsorção. Para potencializar e auxiliar na prospecção de novas aplicações é fundamental conhecer melhor as propriedades do material. Neste trabalho foi feita esta caracterização morfológica, espectroscópica e elementar das cinzas do bagaço da cana-de-açúcar provenientes de três diferentes usinas e duas diferentes safras e a prospecção de seu uso como adsorvente. As partículas das cinzas foram separadas de acordo com sua densidade e para a caracterização foi utilizada a técnica de FTIR na investigação dos grupos químicos presentes nas amostras e MEV juntamente com o EDS para a caracterização morfológica e elementar. As cenosferas, partículas esféricas presentes nas cinzas, foram identificadas como estruturas coreshell onde o core é composto por um misto de óxidos metálicos e o shell composto por dióxido de silício. A correlação entre a razão da abundância relativa entre os grupos de carbonila e hidroxila e a distribuição mássica dos extratos granulométricos, foi usada como medida indireta do nível de oxidação das diferentes amostras. Quanto à sua capacidade de adsorção, as cinzas mostraram afinidade na adsorção do corante azul de metileno com uma capacidade de adsorção de 39mg de corante por grama de cinza usada em contraste com a baixa adsorção apresentada para a solução de cromato de potássio com 1,2 mg por grama de cinza.
5
Kiani, Ali. "Concentration and recovery of positively buoyant cenospheres using an inverted REFLUX classifier". Thesis, 2017. http://hdl.handle.net/1959.13/1335572.
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Research Doctorate - Doctor of Philosophy (PhD)This thesis is concerned with investigating the application of the Inverted REFLUX™ Classifier (IRC™) for separating positively buoyant particles from other negatively buoyant particles. This innovative technology was investigated here for the first time to recover valuable cenospheres, less dense than water, from the fly ash waste of a coal fired power station. Annually, millions of tonnes of fly ash generated from burning coal are discarded to the land surrounding power stations, causing long-lasting environmental and health issues. Fly ash contains valuables components such as cenospheres, unburnt carbon, metals and trace elements. The cenospheres are hollow micro-shells consisting of oxides of silicon and aluminium. These particles represent one of the most valuable components found in fly ash, but at low levels of order 1 wt.%. The particles offer superior properties such as high insulation, high strength, and low density, and hence are valued sometimes up to $ 2000 per tonne. They are positively buoyant in water, and hence wet gravity separation offers the potential for their separation from the negatively buoyant fly ash particles. In this study, wet gravity separation in an Inverted REFLUX™ Classifier was investigated to recover and concentrate cenospheres. The Inverted REFLUX™ Classifier (IRC™) consisted of 1-metre long parallel inclined channels located underneath a 1-metre long vertical liquid fluidized bed. Downwards fluidization was supplied through a distributor at the top for the purpose of washing high density slimes from the low density cenospheres. The inclined channels enhanced the segregation rate of the cenosphere particles leading to a throughput advantage over a conventional fluidized bed. Following preliminary experiments it was shown, using the correlation derived by Laskovski et al. (2006), the throughput advantage of the IRC™ was 32. In other words, for a given separation performance, the feed rate per unit of vessel area to the IRC™ can be increased to a level 32 times higher than for a conventional fluidized bed. These preliminary studies were based on using a model feed, a mixture of commercial cenospheres and silica flour. Then, a real fly ash feed containing around 0.51 wt.% cenospheres was used. At a solids throughput of about 2.3 t/(m² h), a product grade of 76 wt.% and a recovery of about 42 wt.% were obtained, corresponding to an upgrade of about 151. By increasing the product rate, the recovery of cenospheres increased to about 64 wt.%, while the upgrade was reduced to 33. A more systematic study was then conducted using a new feed consisting of about 1 wt.% cenospheres, focussed on the role of the solids concentration in effecting enhanced segregation. Based on the study by Batchelor and Van Rensburg (1986), it was hypothesised that a bulk streaming phenomenon should develop in the inclined channels at sufficiently high cenosphere and fly ash concentrations. Different feed solids concentrations from 10 wt.% to 46 wt.% were used, for a fixed feed flow rate, fluidization rate, and volumetric split between the overflow and underflow. As the feed solids concentration increased from 10.1 wt.% to about 38.1 wt.%, the recovery of the cenospheres increased from 61.7 wt.% to an optimum recovery of 89.9 wt.%, before declining rapidly to a recovery of 60.2 wt.% at a feed solids concentration of about 46.4 wt.%. At the optimum feed solids concentration of 38.1 wt.%, the solids throughput was a remarkable 3.1 t/(m² h), and the upgrade in the cenospheres concentration was 58.6. The overall throughput advantage at the optimum condition was found to be 54, based on a partition curve analysis of the separation size of the cenospheres. More detailed analysis indicated that the inclined channels delivered a throughput advantage of 18, hence it was concluded that a further throughput advantage of 3 was most likely due to the bulk streaming phenomenon. The sharpest size classification was also evident at the optimum feed solids concentration, providing the d₂₅ = 31.5 μm, d₅₀ = 36.5 μm, and d₇₅ = 50.0 μm. The separation performance at the optimum feed solids concentration was further investigated at different feed flow rates and product split ratios, in order to provide the optimum operating conditions to be used in the pilot scale investigation. The potential to scale-up the process by a factor of 10 was investigated using a pilot scale device with cross-section 0.3 m × 0.3 m. The separation performance in the pilot scale IRC™ was compared with that obtained from the laboratory scale performance. The results were found to be consistent. At a solids throughput of about 4.1 t/(m² h), a cenosphere recovery of about 80 wt.% and a high upgrade of 19 were achieved while at a lower product split ratio, a slightly lower recovery of 75 wt.% and a higher upgrade of 38 were achieved. This part of the study provides the necessary basis for justifying a full scale investigation of this technology. The potential benefits of a multi-stage arrangement were also investigated. A fly ash feed with the cenosphere grade of about 0.9 wt.% was subjected to a three-stage IRC™ separation. At the end of the process, a very high grade product of about 97 wt.% (almost pure on a volume basis) was achieved. However, the overall three stage recovery fell to around 50 wt.%, mainly due to the low separation efficiency in Stage 2 of the process. In fact, the second stage involved a very dilute feed, and hence a likely explanation is the lack of the bulk streaming phenomenon under these conditions. It is therefore concluded that the single stage separation offers the best option. A further fly ash feed containing larger cenospheres at an even higher cenosphere concentration was examined in the IRC™. At a high solids throughput of 4.9 t/(m² h), the cenosphere recovery was found to be 93 wt.%, and product grade 80 wt.%. This final study demonstrated the remarkable separation performance that can be achieved, and the fact that in the presence of larger cenospheres high recoveries and upgrades are possible at even higher solids throughputs. The work was also consistent with the earlier findings which show the benefit of a higher cenosphere feed concentration in promoting the bulk streaming phenomenon. This study has investigated for the first time an entirely new technology for separating very low grade buoyant particles from a very high concentration of ultrafine high density particles. The approach is effectively an inverted application of the REFLUX™ Classifier. This thesis has therefore incorporated the analysis developed for the REFLUX™ Classifier, providing a clear basis for assessing this new, inverted, system. Through this approach it has been possible to infer the existence of hydrodynamic benefits that arise from operating at higher concentrations, and in turn elevated solids processing rates. Further investigation of the bulk streaming phenomenon within inclined systems is recommended in order to identify the precise onset of the phenomenon. This benefit has not previously been identified in the separation of cenospheres from fly ash. The overall findings from this study demonstrate a separation performance significantly better than achieved previously by any other technology to date.
Części książek na temat "Fly Ash Cenosphere"
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Beddu, Salmia, Mahyun Mohd Zainoodin, Zakaria Che Muda, Daud Mohamad, Fadzli Mohamed Nazri, Zarina Itam i Siti Nabihah Sadon. "Characteristic Study on Malaysia Power Plant Fly Ash Cenosphere". W Proceedings of AICCE'19, 1229–37. Cham: Springer International Publishing, 2019. http://dx.doi.org/10.1007/978-3-030-32816-0_94.
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Bora, Pritom J., K. J. Vinoy, Kishore, Praveen C. Ramamurthy i Giridhar Madras. "Lightweight Microwave Absorber from Industrial Waste Fly Ash Cenosphere". W Lecture Notes in Electrical Engineering, 459–66. Singapore: Springer Singapore, 2017. http://dx.doi.org/10.1007/978-981-10-4286-7_45.
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Shende, Diwakar Z., Kailas L. Wasewar i Shraddha S. Wadatkar. "Target-Specific Applications of Fly Ash Cenosphere as Smart Material". W Handbook of Nanomaterials and Nanocomposites for Energy and Environmental Applications, 3349–69. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-36268-3_207.
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Shende, Diwakar Z., Kailas L. Wasewar i Shraddha S. Wadatkar. "Target-Specific Applications of Fly Ash Cenosphere as Smart Material". W Handbook of Nanomaterials and Nanocomposites for Energy and Environmental Applications, 1–22. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-11155-7_207-1.
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Patel, S. K., i A. N. Nayak. "Study on Specific Compressive Strength of Concrete with Fly Ash Cenosphere". W Recent Developments in Sustainable Infrastructure, 561–72. Singapore: Springer Singapore, 2020. http://dx.doi.org/10.1007/978-981-15-4577-1_47.
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Yang, Lei, Zhiwei Peng, Yawen Huang, Liancheng Wang, Leixia Zheng, Mingjun Rao, Guanghui Li i Tao Jiang. "Preparation of Thermal Insulation Materials from Ferronickel Slag with Addition of Fly Ash Cenosphere". W The Minerals, Metals & Materials Series, 217–26. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-36628-5_20.
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Zhu, Guangyan, Zhiwei Peng, Lei Yang, Wenxing Shang i Mingjun Rao. "Microstructural Evolution of Thermal Insulation Materials Prepared by Sintering of Ferronickel Slag and Fly Ash Cenosphere". W The Minerals, Metals & Materials Series, 143–49. Cham: Springer International Publishing, 2022. http://dx.doi.org/10.1007/978-3-030-92388-4_14.
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Fang, Xiaolei, Zhiwei Peng, Lei Yang, Guangyan Zhu i Mingjun Rao. "Conversion of Ferronickel Slag to Thermal Insulation Materials by Microwave Sintering: Effect of Fly Ash Cenosphere Addition". W The Minerals, Metals & Materials Series, 219–28. Cham: Springer Nature Switzerland, 2023. http://dx.doi.org/10.1007/978-3-031-22576-5_20.
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Vinu Kumar, S. M., K. L. Senthil kumar i B. Suresha. "Effect of Ultraviolet (UV) Radiation on Mechanical Behavior of Bi-directional Carbon Fabric Reinforced Epoxy Composites Impregnated with Fly Ash Cenosphere Particles". W Springer Proceedings in Materials, 1–9. Singapore: Springer Singapore, 2021. http://dx.doi.org/10.1007/978-981-15-8319-3_1.
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Hung, L. V., N. V. Tuan i L. T. Thanh. "Experimental Investigation of High-Strength Lightweight Concrete Using Fly Ash Cenospheres". W Lecture Notes in Civil Engineering, 637–45. Singapore: Springer Singapore, 2021. http://dx.doi.org/10.1007/978-981-16-7160-9_64.
Pełny tekst źródłaStreszczenia konferencji na temat "Fly Ash Cenosphere"
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"Utilization of Cenosphere in Manufacturing of Fly Ash Brick". W Recent Advancements in Geotechnical Engineering. Materials Research Forum LLC, 2021. http://dx.doi.org/10.21741/9781644901618-13.
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Abstract. Our project was built with cenosphere material and low-density brick. The cenosphere bricks may be lighter and stronger than traditional fly ash bricks. Cement is used to replace the cenosphere in fly ash bricks in the following proportions: 230mm x 100mm x 75mm sample size for blend percentage of cenosphere, fly ash, and quarry dust. The results show how compressive strength and water absorption vary with curing age for mixed proportions of the materials mentioned previously. Then we can use the 230mm x 100mm x 75mm specimen size to cast bricks with various mix proportions of cenosphere, fly ash, and quarry dust. The weight, compressive strength, and water absorption of the cenosphere with various proportions of fly ash bricks were then compared. Via comprehensive laboratory work, this investigation is primarily based on optimizing the compressive strength of newly formed bricks thus minimizing weight density and water absorption. A definitive goal of undertaking this point as project work is to recognize factors influencing the different properties of bricks.
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Che, Ru-Xin, i Ying-Juan Ni. "Preparation and microwave absorption property of the core-nanoshell composite absorbers with magnetic fly-ash hollow cenosphere as nuclear". W Second International Conference on Smart Materials and Nanotechnology in Engineering, redaktorzy Jinsong Leng, Anand K. Asundi i Wolfgang Ecke. SPIE, 2009. http://dx.doi.org/10.1117/12.837464.
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Bora, Pritom J., Bibhusita Mahanta, Kishore K i Praveen C. Ramamurthy. "Design of Bi-Layered Strong Microwave Absorber Based on Polymer-Fly Ash Cenosphere Composite With A Data-Driven Approach". W 2022 IEEE International Conference on Emerging Electronics (ICEE). IEEE, 2022. http://dx.doi.org/10.1109/icee56203.2022.10117614.
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Ukoba, Kingsley, Samuel Popoola, Olatunde Israel, Patrick Imoisili i Tien-Chien Jen. "Development and Characterization of Fly Ash Nanoparticles Reinforced Epoxy Resin Composite for Acoustic Applications". W ASME 2020 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2020. http://dx.doi.org/10.1115/imece2020-23708.
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Abstract Noise is an unwanted sound; requires reduction and control through the use of absorptive materials. This is imperative due to the adverse effect noise poses to human health, knowledge dissemination, and tranquility which is increasing daily due to industrialization and heightened allied activities. The use of natural and synthetic reinforced composites in noise pollution control is an emerging area of research. This study aims to develop and characterize fly ash nanoparticles reinforced epoxy resin composite for acoustic applications. Samples were prepared with fly ash nanoparticles reinforcement at 5%, 10%, 15%, 20%, and 25% and investigation of noise reduction coefficient (NRC), porosity and mechanical properties (hardness, impact, flexural strength) of samples were done. Cenospheres were obtained when fly ash particles were characterized separately with the aid of sieve analysis and x-ray fluorescence analysis. The cenospheres are hollow spherical and lightweight, inertfiller material. Correlation between porosity of the samples and their sound absorption properties was observed and showed that as porosity increased, the NRC values increased and as the porosity decreased the NRC values decreased. It was also observed that heat of polymerization, fly ash nanoparticles structure and air bubbles during sample preparation (mixing) influenced the porosity values which in turn influenced the NRC values of the composite. There was also a steady decrease in mechanical properties, as reinforcements were added (5%, 10%, 15%, 20%, and 25%), this was attributed to the high surface areas and shape of reinforcement added.
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Fan, GuoLi, RongYu Si i Ming Yuan. "The effect of particles integrity on the damping capacities of fly-ash cenospheres/AZ91D composites". W 2015 2nd International Conference on Machinery, Materials Engineering, Chemical Engineering and Biotechnology. Paris, France: Atlantis Press, 2016. http://dx.doi.org/10.2991/mmeceb-15.2016.101.
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