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 Crystal Growth on Cenospheres from High-Calcium Fly Ash

Crystals ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 919
Author(s):  
Sorachon Yoriya ◽  
Phattarathicha Tepsri
Keyword(s):  
Crystal Growth ◽  
Fly Ash ◽  
Chemical Composition ◽  
Calcium Content ◽  
Centrifugal Method ◽  
Preferential Formation ◽  
Carbonate Formation ◽  
Mineral Phases ◽  
Gravity Settling ◽  
High Calcium

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.

Variability and Trends in Iowa Fly Ashes

1986 ◽  
Vol 86 ◽  
Author(s):  
Scott Schlorholtz ◽  
Ken Bergeson ◽  
Turgut Demirel
Keyword(s):  
Fly Ash ◽  
Chemical Composition ◽  
Power Plant ◽  
Coefficient Of Variation ◽  
Power Plants ◽  
Chemical Properties ◽  
Physical Analysis ◽  
Fly Ashes ◽  
High Calcium ◽  
Physical And Chemical

ABSTRACTAn investigation has been made of the variability of physical and chemical properties of high-calcium (Class C) fly ashes from four Iowa power plants. The investigation summarizes results obtained from three years (1983 through 1985) of monitoring of the various power plants. All four of the power plants burn low-sulfur, sub-bituminous coal from Wyoming. Fly ash samples were obtained from the power plants in accordance to the procedures described in ASTM C 311. Laboratory testing methods were similar to those specified by ASTM C 311. During the three year period, 102 samples were subjected to chemical and physical analysis while an additional 349 samples were subjected to physical analysis only. In general, the four power plants produce fly ashes of similar mineralogy and chemical composition. The observed time variation of the chemical composition of fly ash from a single power plant was quite small. The sulfur content consistently showed the largest coefficient of variation of the 10 elements studied. Physical characteristics of the fly ashes (as measured by ASTM tests) were also fairly uniform over long periods of time, when considered on an individual power plant basis. Fineness, when measured by wet washing using a 325 mesh sieve, consistently exhibited the largest coefficient of variation of any of the physical properties studied.

Mineralogy and Chemical Composition of High-Calcium Fly Ashes and Density Fractions from a Coal-Fired Power Plant in China

2010 ◽  
Vol 24 (2) ◽  
pp. 834-843 ◽  
Author(s):  
Yongchun Zhao ◽  
Junying Zhang ◽  
Chong Tian ◽  
Hailong Li ◽  
Xinyu Shao ◽  
...  
Keyword(s):  
Chemical Composition ◽  
Power Plant ◽  
Fly Ashes ◽  
Density Fractions ◽  
High Calcium

Potential of Fly Ash Utilization for the Clinker Substitution in Cement Industry in Thailand

2017 ◽  
Vol 883 ◽  
pp. 97-101
Author(s):  
Wisanu Sairatanathongkham ◽  
Weerin Wangjiraniran
Keyword(s):  
Fly Ash ◽  
Power Plant ◽  
Cement Industry ◽  
Base Case ◽  
Full Potential ◽  
Potential Evaluation ◽  
Fly Ash Utilization ◽  
Business As Usual ◽  
Mae Moh ◽  
Clinker Production

The main objective of this article is to forecast CO2 mitigation from clinker production and to evaluate Fly Ash potential, used Clinker Substitution for CO2 mitigation in cement industry between years 2015-2036 in Thailand following information of the Thailand's power developments plan (PDP2015). PDP2015 forecasts the potential of fly ash in the year 2036 which is estimated at 3.94 M ton and 48.76 M TonCO2 of CO2 emission from 58.01 M Ton of clinker production process. The methodology which is used for potential evaluation of fly ash and amount of CO2 can evaluate from Mae Moh power plant technology. 1 MW can occur 952.3427 Ton and amount of CO2 emission from utilizing is 0.825 TonCO2/TonneCli which is a default value of CSI (Cement Sustainability Initiative).The three different scenarios are used to analysis in this study. The condition of Business As Usual (BAU) scenario is the need of technology, used in 2015 as a base case. The full potential scenario (FP) is represent to the 100% fly ash using. The final scenario is called Zoning scenario (Z scenario) which consists of price rate (270 THB per Ton) and transportation rate (6 THB per kilometer of fly ash). From the result, in 2036 fly ash occur 7.46 M Ton that can mitigate CO2 volume up to 6.15 M TonCO2

scholarly journals The Compressive Strength and Microstructure of Alkali-Activated Binary Cements Developed by Combining Ceramic Sanitaryware with Fly Ash or Blast Furnace Slag

Minerals ◽  
2018 ◽  
Vol 8 (8) ◽  
pp. 337 ◽  
Author(s):  
Juan Cosa ◽  
Lourdes Soriano ◽  
María Borrachero ◽  
Lucía Reig ◽  
Jordi Payá ◽  
...  
Keyword(s):  
Compressive Strength ◽  
Blast Furnace ◽  
Fly Ash ◽  
Blast Furnace Slag ◽  
Calcium Content ◽  
Partial Replacement ◽  
Alkali Activation ◽  
High Calcium ◽  
Furnace Slag ◽  
Alkali Activated

The properties of a binder developed by the alkali-activation of a single waste material can improve when it is blended with different industrial by-products. This research aimed to investigate the influence of blast furnace slag (BFS) and fly ash (FA) (0–50 wt %) on the microstructure and compressive strength of alkali-activated ceramic sanitaryware (CSW). 4 wt % Ca(OH)2 was added to the CSW/FA blended samples and, given the high calcium content of BFS, the influence of BFS was analyzed with and without adding Ca(OH)2. Mortars were used to assess the compressive strength of the blended cements, and their microstructure was investigated in pastes by X-ray diffraction, thermogravimetry, and field emission scanning electron microscopy. All the samples were cured at 20 °C for 28 and 90 days and at 65 °C for 7 days. The results show that the partial replacement of CSW with BFS or FA allowed CSW to be activated at 20 °C. The CSW/BFS systems exhibited better mechanical properties than the CSW/FA blended mortars, so that maximum strength values of 54.3 MPa and 29.4 MPa were obtained in the samples prepared with 50 wt % BFS and FA, respectively, cured at 20 °C for 90 days.

Effect of Silica to Alumina Ratio on the Compressive Strength of Class C Fly Ash-Based Geopolymers

2015 ◽  
Vol 659 ◽  
pp. 80-84 ◽  
Author(s):  
Patthamaporn Timakul ◽  
Kanyarat Thanaphatwetphisit ◽  
Pavadee Aungkavattana
Keyword(s):  
Compressive Strength ◽  
Fly Ash ◽  
Curing Temperature ◽  
Infrared Study ◽  
Xrd Study ◽  
High Calcium ◽  
High Calcium Fly Ash ◽  
Solid Part ◽  
Class C ◽  
Mae Moh

This study investigated the effect of silica to alumina ratio on the compressive strength of geopolymer. The high calcium fly ash (Class C, ASTM 618) wastes from Mae Moh Thailand power plant, which is SiO2 (30.97%) and Al2O3 (17.16%)-rich materials was employed as the main solid part to prepare geopolymers, apart from kaolinite. The combination of sodium hydroxide (NaOH), sodium silicate (Na2SiO3) solution, and distilled water as 1:1:4 mass ratios were used as the liquid activator. The curing temperature in the oven was fixed at 75oC and varied curing time for 24, 48, 72 and 96 hours. Further curing was done at room temperature for 28 days before characterizations. XRD study of synthesized geopolymers showed a hump of not well-defined peaks and some major peaks of quartz, and unreacted kaolinite indicating the incomplete geopolymerization reaction. Infrared study showed the Al-O-Si and Si-O-Si bonds in all geopolymers samples. The compressive strength of geopolymer increased from 32 to 40 MPa when the ratio of SiO2 : Al2O3 was increased from 2.60 to 2.65. However, the compressive strength was decreased after increasing the SiO2 : Al2O3 ratio from 2.65 to 3.0. The highest compressive strength was found when the SiO2 : Al2O3 ratio was 2.65 with the curing condition at 75oC for 96 h which the samples also possessed high density.

Sulfur-Containing Composite Material for the Concrete Production

2016 ◽  
Vol 712 ◽  
pp. 171-175 ◽  
Author(s):  
Irina Frolova ◽  
Viktor V. Tikhonov ◽  
Anna P. Poltoranina ◽  
Natalya Usoltseva ◽  
Shuang Cheng Fu ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Particle Size ◽  
Composite Material ◽  
Fly Ash ◽  
Chemical Composition ◽  
Power Plant ◽  
Mechanical Characteristics ◽  
Combined Heat And Power ◽  
Concrete Production ◽  
Sulfur Containing

The chemical composition and particle size distribution as well as the physical-mechanical characteristics of fly ash of Krasnokamensk combined heat and power plant (CHPP) were determined. The revealed features provided the development of the technology of fly ash enrichment. The composite building material based on both fly ash of Krasnokamensk CHPP and technical sulfur was developed. Aluminum chloride was proposed to be used as modifier. The basic physical-mechanical properties of sulfur crushed stone were investigated.

scholarly journals Effect of Additive Material on Controlling Chromium (Cr) Leaching from Coal Fly Ash

Minerals ◽  
2020 ◽  
Vol 10 (6) ◽  
pp. 563
Author(s):  
Erda Rahmilaila Desfitri ◽  
Ulung Muhammad Sutopo ◽  
Yukio Hayakawa ◽  
Shinji Kambara
Keyword(s):  
Fly Ash ◽  
Inductively Coupled Plasma ◽  
Power Plants ◽  
Coal Fly Ash ◽  
Thermal Power ◽  
Calcium Content ◽  
High Calcium ◽  
Cr Concentration ◽  
Additive Materials ◽  
Sludge Ash

Coal fly ash contains a considerable number of toxic elements that can be leached into the environment, such as chromium (Cr), thereby quickly leading to severe contaminations. In this research, the leaching behaviors of Cr were analyzed from 14 kinds of coal fly ash samples collected from the electrostatic precipitators of coal-fired thermal power plants in Japan. The level of Cr concentration found in the samples varied from 0.00 to 82.93 μg/L. However, Cr toxicity depends on its valence state; Cr6+ is more toxic than Cr3+. Additive materials containing high calcium content were used to control the leaching concentration of Cr, such as Ca(OH)2, paper sludge ash, and blast furnace cement. This research used several instruments. An X-ray fluorescence was adopted to measure the major chemical composition of the fly ash samples and the additive materials. A thermogravimetric analyzer was used to examine the calcium compounds in the additive materials. Inductively coupled plasma was used to determine the Cr leaching concentrations from the fly ash samples. Findings showed that the three-additive mixture had a promising effect on controlling the Cr leaching concentrations. These results were also supported by FactSage 7.2 simulation.

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