Effects of SiO2/Al2O3 Ratios on Sintering Characteristics of Synthetic Coal Ash
This article explores the effects of SiO2/Al2O3 ratios (S/A) on sintering characteristics and provides guidance for alleviating ash depositions in a large-scale circulation fluidized bed. Five synthetic coal ash (SCA) samples with different S/As were treated in a muffle furnace for 12 h at different...
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MDPI AG
2017-02-01
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| Series: | Energies |
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| Online Access: | http://www.mdpi.com/1996-1073/10/2/242 |
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| author | Hongwei Hu Kun Zhou Kesheng Meng Lanbo Song Qizhao Lin |
| author_facet | Hongwei Hu Kun Zhou Kesheng Meng Lanbo Song Qizhao Lin |
| author_sort | Hongwei Hu |
| collection | DOAJ |
| description | This article explores the effects of SiO2/Al2O3 ratios (S/A) on sintering characteristics and provides guidance for alleviating ash depositions in a large-scale circulation fluidized bed. Five synthetic coal ash (SCA) samples with different S/As were treated in a muffle furnace for 12 h at different temperatures (from 773 K to 1373 K, in 100 K intervals). The morphological and chemical results of the volume shrinkage ratio (VSR), thermal deformation analysis by dilatometer (DIL), scanning electron microscope (SEM), X-ray photoelectron spectrometer (XPS), and X-ray diffraction (XRD) were combined to describe the sintering characteristics of different samples. The results showed that the sintering procedure mainly occurred in the third sintering stage when the temperature was over 1273 K, accompanied with significant decreases in the VSR curve. Excess SiO2 (S/A = 4.5) resulted in a porous structure while excess Al2O3 (S/A = 0.5) brought out large aggregations. The other three samples (S/A = 1.5, 2.5, 3.5) are made up of an amorphous compacted structure and are composed of low fusion temperature materials (e.g., augite and wadsleysite.). Sintering temperatures first dramatically decrease to a low level and then gradually rise to a high level as S/A increases, suggesting that Al2O3-enriched additives are more effective than SiO2enriched additives in alleviating depositions. |
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| id | doaj.art-99aa0ae6ecf2467c873ea3fb8a931ead |
| institution | Directory Open Access Journal |
| issn | 1996-1073 |
| language | English |
| last_indexed | 2024-04-14T00:56:26Z |
| publishDate | 2017-02-01 |
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| spelling | doaj.art-99aa0ae6ecf2467c873ea3fb8a931ead2022-12-22T02:21:35ZengMDPI AGEnergies1996-10732017-02-0110224210.3390/en10020242en10020242Effects of SiO2/Al2O3 Ratios on Sintering Characteristics of Synthetic Coal AshHongwei Hu0Kun Zhou1Kesheng Meng2Lanbo Song3Qizhao Lin4Department of Thermal Science and Energy Engineering, University of Science and Technology of China, Hefei 230027, ChinaDepartment of Thermal Science and Energy Engineering, University of Science and Technology of China, Hefei 230027, ChinaDepartment of Thermal Science and Energy Engineering, University of Science and Technology of China, Hefei 230027, ChinaDepartment of Thermal Science and Energy Engineering, University of Science and Technology of China, Hefei 230027, ChinaDepartment of Thermal Science and Energy Engineering, University of Science and Technology of China, Hefei 230027, ChinaThis article explores the effects of SiO2/Al2O3 ratios (S/A) on sintering characteristics and provides guidance for alleviating ash depositions in a large-scale circulation fluidized bed. Five synthetic coal ash (SCA) samples with different S/As were treated in a muffle furnace for 12 h at different temperatures (from 773 K to 1373 K, in 100 K intervals). The morphological and chemical results of the volume shrinkage ratio (VSR), thermal deformation analysis by dilatometer (DIL), scanning electron microscope (SEM), X-ray photoelectron spectrometer (XPS), and X-ray diffraction (XRD) were combined to describe the sintering characteristics of different samples. The results showed that the sintering procedure mainly occurred in the third sintering stage when the temperature was over 1273 K, accompanied with significant decreases in the VSR curve. Excess SiO2 (S/A = 4.5) resulted in a porous structure while excess Al2O3 (S/A = 0.5) brought out large aggregations. The other three samples (S/A = 1.5, 2.5, 3.5) are made up of an amorphous compacted structure and are composed of low fusion temperature materials (e.g., augite and wadsleysite.). Sintering temperatures first dramatically decrease to a low level and then gradually rise to a high level as S/A increases, suggesting that Al2O3-enriched additives are more effective than SiO2enriched additives in alleviating depositions.http://www.mdpi.com/1996-1073/10/2/242synthetic coal ash (SCA)sinteringdilatometereutectics |
| spellingShingle | Hongwei Hu Kun Zhou Kesheng Meng Lanbo Song Qizhao Lin Effects of SiO2/Al2O3 Ratios on Sintering Characteristics of Synthetic Coal Ash Energies synthetic coal ash (SCA) sintering dilatometer eutectics |
| title | Effects of SiO2/Al2O3 Ratios on Sintering Characteristics of Synthetic Coal Ash |
| title_full | Effects of SiO2/Al2O3 Ratios on Sintering Characteristics of Synthetic Coal Ash |
| title_fullStr | Effects of SiO2/Al2O3 Ratios on Sintering Characteristics of Synthetic Coal Ash |
| title_full_unstemmed | Effects of SiO2/Al2O3 Ratios on Sintering Characteristics of Synthetic Coal Ash |
| title_short | Effects of SiO2/Al2O3 Ratios on Sintering Characteristics of Synthetic Coal Ash |
| title_sort | effects of sio2 al2o3 ratios on sintering characteristics of synthetic coal ash |
| topic | synthetic coal ash (SCA) sintering dilatometer eutectics |
| url | http://www.mdpi.com/1996-1073/10/2/242 |
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