Microanalytical characterization (AEM) of glassy spheres and anhydrite from a high-calcium lignite fly ash from Germany

1995 ◽  
Vol 25 (6) ◽  
pp. 1369-1377 ◽  
Author(s):  
Michael Enders
Keyword(s):  
Fly Ash ◽  
Lignite Fly Ash ◽  
High Calcium

scholarly journals Separation Process and Microstructure-Chemical Composition Relationship of Cenospheres from Lignite Fly Ash Produced from Coal-Fired Power Plant in Thailand

2020 ◽  
Vol 10 (16) ◽  
pp. 5512
Author(s):  
Sorachon Yoriya ◽  
Phattarathicha Tepsri
Keyword(s):  
Fly Ash ◽  
Chemical Composition ◽  
Power Plant ◽  
Particle Diameter ◽  
Calcium Content ◽  
Aluminosilicate Glass ◽  
Structure Property ◽  
Lignite Fly Ash ◽  
High Calcium ◽  
Mae Moh

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.

scholarly journals Separation of Cenospheres from Lignite Fly Ash Using Acetone–Water Mixture

2019 ◽  
Vol 9 (18) ◽  
pp. 3792 ◽  
Author(s):  
Yoriya ◽  
Intana ◽  
Tepsri
Keyword(s):  
Fly Ash ◽  
Separation Efficiency ◽  
Water Mixture ◽  
Carbonate Concentration ◽  
Lignite Fly Ash ◽  
Acetone Water ◽  
Structure Morphology ◽  
High Calcium ◽  
Self Association

This work reports on the separation of cenospheres from lignite fly ash through a wet separation process-the sink-float method. A better quality of cenospheres could be achieved through a physical–chemical approach using an acetone–water mixture as a medium. This work aimed to elucidate the correlation between the structure, morphology, and composition and medium fraction variables, with data for the freshly prepared and the reused mixtures presented for comparison. The work covers a study of the macrocomponent composition of an Fe2O3–SiO2–Al2O3 system, highlighting the pair dependences of SiO2–Al2O3, Al2O3–Fe2O3, and SiO2/Al2O3–Al2O3 and revealing an interesting result in terms of geochemical characteristics categorizing the collected cenosphere fractions separated from high-calcium class C fly ash produced from a lignite coal power plant in Thailand (as magnetic cenospheres). The CaO and SO3 contents increased monotonically with increased water content, particularly for the CaO composition profile, which was found to be similar to the increased carbonate concentration measured from the mixtures after use. The physicochemical properties in terms of the self-association ability of the acetone–water mixing phase is believed to have played an important role in determining the intermolecular interactions and reactivity of ions in the liquid phase, consequently affecting the separation efficiency, recovery yield, and quality of cenospheres.

Natural fiber reinforced high calcium fly ash geopolymer mortar

2020 ◽  
Vol 241 ◽  
pp. 118143 ◽  
Author(s):  
Ampol Wongsa ◽  
Ronnakrit Kunthawatwong ◽  
Sakchai Naenudon ◽  
Vanchai Sata ◽  
Prinya Chindaprasirt
Keyword(s):  
Fly Ash ◽  
Natural Fiber ◽  
Fiber Reinforced ◽  
High Calcium ◽  
High Calcium Fly Ash

Monitoring of Fluctuations in the Physical and Chemical Properties of a High-Calcium Fly Ash

1987 ◽  
Vol 113 ◽  
Author(s):  
Scott Schlorholtz ◽  
Ken Bergeson ◽  
Turgut Demirel
Keyword(s):  
Fly Ash ◽  
Chemical Properties ◽  
Operating Conditions ◽  
Physical And Chemical Properties ◽  
X Ray Diffraction ◽  
X Ray ◽  
Morphological Studies ◽  
High Calcium ◽  
Physical And Chemical ◽  
And Chemical Properties

ABSTRACTThe physical and chemical properties of fly ash produced at Ottumwa Generating Station have been monitored since April, 1985. The fly ash is produced from burning a low sulfur, sub-bituminous coal obtained from the Powder River Basin near Gillette, Wyoming. One-hundred and sixty samples of fly ash were obtained during the two year period. All of the samples were subjected to physical testing as specified by ASTM C 311. About one-hundred of the samples were also subjected to a series of tests designed to monitor the self-cementing properties of the fly ash. Many of the fly ash samples were subjected to x-ray diffraction and fluorescence analysis to define the mineralogical and chemical composition of the bulk fly ash as a function of sampling date. Hydration products in selected hardened fly ash pastes, were studied by x-ray diffraction and scanning electron microscopy. The studies indicated that power plant operating conditions influenced the compressive strength of the fly ash paste specimens. Mineralogical and morphological studies of the fly ash pastes indicated that stratlingite formation occurred in the highstrength specimens, while ettringite was the major hydration product evident in the low-strength specimens.

scholarly journals Effect of Lignite Fly Ash on the Growth and Reproduction of Earthworm Eisenia fetida

2009 ◽  
Vol 6 (2) ◽  
pp. 511-517 ◽  
Author(s):  
S. Sarojini ◽  
S. Ananthakrishnasamy ◽  
G. Manimegala ◽  
M. Prakash ◽  
G. Gunasekaran
Keyword(s):  
Fly Ash ◽  
Eisenia Fetida ◽  
Power Plants ◽  
Thermal Power ◽  
Biological Properties ◽  
Cow Dung ◽  
Physical Chemical ◽  
Lignite Fly Ash ◽  
Agricultural Use ◽  
Growth And Reproduction

Fly ash is an amorphous ferroalumino silicate, an important solid waste around thermal power plants. It creates problems leading to environmental degradation due to improper utilization or disposal. However, fly ash is a useful ameliorant that may improve the physical, chemical and biological properties of soils and is a source of readily available plant macro and micronutrients when it is used with biosolids. Supply of nutrients from fly ash with biosolids may enhance their agricultural use. The growth and reproduction ofEisenia fetidawas studied during vermicomposting of fly ash with cowdung and pressmud in four different proportions (T1,T2,T3& T4) and one controli.e.,cow dung and pressmud alone. The growth, cocoon and hatchlings production were observed at the interval of 15 days over a period of 60 days. The maximum worm growth and reproduction was observed in bedding material alone. Next to that the T1was observed as the best mixture for vermiculture.

scholarly journals Characterization of the Physical, Chemical, and Adsorption Properties of Coal-Fly-Ash–Hydroxyapatite Composites

Minerals ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 774
Author(s):  
Eleonora Sočo ◽  
Dorota Papciak ◽  
Magdalena M. Michel ◽  
Dariusz Pająk ◽  
Andżelika Domoń ◽  
...  
Keyword(s):  
Fly Ash ◽  
Coal Fly Ash ◽  
Thermal Power ◽  
Synthesis Conditions ◽  
High Calcium ◽  
Ft Ir ◽  
Ir Analysis ◽  
Wet Synthesis

(1) Hydroxyapatite (Hap), which can be obtained by several methods, is known to be a good adsorbent. Coal fly ash (CFA) is a commonly reused byproduct also used in environmental applications as an adsorbent. We sought to answer the following question: Can CFA be included in the method of Hap wet synthesis to produce a composite capable of adsorbing both heavy metals and dyes? (2) High calcium lignite CFA from the thermal power plant in Bełchatów (Poland) was used as the base to prepare CFA–Hap composites. Four types designated CFA–Hap1–4 were synthesized via the wet method of in situ precipitation. The synthesis conditions differed in terms of the calcium reactants used, pH, and temperature. We also investigated the equilibrium adsorption of Cu(II) and rhodamine B (RB) on CFA–Hap1–4. The data were fitted using the Langmuir, Freundlich, and Redlich–Peterson models and validated using R2 and χ2/DoF. Surface changes in CFA–Hap2 following Cu(II) and RB adsorption were assessed using SEM, SE, and FT-IR analysis. (3) The obtained composites contained hydroxyapatite (Ca/P 1.67) and aluminosilicates. The mode of Cu(II) and RB adsorption could be explained by the Redlich–Peterson model. The CFA–Hap2 obtained using CFA, Ca(NO3)2, and (NH4)2HPO4 at RT and pH 11 exhibited the highest maximal adsorption capacity: 73.6 mg Cu/g and 87.0 mg RB/g. (4) The clear advantage of chemisorption over physisorption was indicated by the Cu(II)–CFA–Hap system. The RB molecules present in the form of uncharged lactone were favorably adsorbed even on strongly deprotonated CFA–Hap surfaces.

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