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Crystalline silica in compressed rice hull coke ash |
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| รหัสดีโอไอ | |
| Creator | Takeshi OKUTANI |
| Title | Crystalline silica in compressed rice hull coke ash |
| Contributor | Eri ICHIKAWA, Hedeaki NAGAI, Toshitaka HASHIMOTO, Tsuyoshi MAKIHATA |
| Publisher | Metallurgy and Materials Science Research Institute, Chulalongkorn University |
| Publication Year | 2561 |
| Journal Title | Journal of Metals, Materials and Minerals |
| Journal Vol. | 28 |
| Journal No. | 1 |
| Page no. | 30-38 |
| Keyword | Rice hull coke, Ash, Potassium Cristobalite, Respirable crystalline silica, Combustion |
| URL Website | http://ojs.materialsconnex.com/index.php/jmmm/index |
| Website title | Journal of Metals, Materials and Minerals |
| ISSN | 8576149 |
| Abstract | Compressed rice hull coke was produced by compressing rice hulls ground to less than 200 ?m diameter at 1.22x106 N/m2 and 310?C with an oxygen deficient atmosphere. The compressed rice hull coke had a 5 cm outer diameter, a 1.5 cm inner diameter and 35 cm length. The density of the coke is 1.2, and, the heat value is 16570 kJทkg-1. In this study, 2 kg coke was combusted at the average temperature of 850?C for 104 min with a maximum temperature of 860?C. The ash was colored black-grey, and the form remained coke. The ash contained 95.4% silica with 9.2% cristobalite and 86.2% amorphous silica. The occupational exposure limits of respirable fraction of crystalline silica such as cristobalite and quartz in floating dust less than the diameter of 7 ?m is 0.025 mg/m3; however, no respirable cristobalite was detected during combustion of the compressed rice hull coke. Cristobalite was not present in floating dust because it melted during the crystallization of amorphous silica to cristobalite. |
