https://scholars.lib.ntu.edu.tw/handle/123456789/408032
Title: | Thermochemical analysis in the presintering phase of aggregates from sludge-marine clay mixes | Authors: | Show K.-Y. Tay J.-H. Lee D.-J. Hong S.-Y. Chien C.-Y. |
Keywords: | Aggregates;Clays;Recycling;Sludge;Temperature;Thermal analysis | Issue Date: | 2006 | Journal Volume: | 18 | Journal Issue: | 1 | Start page/Pages: | 55-60 | Source: | Journal of Materials in Civil Engineering | Abstract: | Rapid industrialization and urbanization in a highly limited land area leads to serious waste disposal problems. Scarcity of land causes the disposal of waste in landfills to be extremely uneconomical. An attractive alternative to waste disposal is conversion of waste into new resources. Past studies have indicated that the conversion of wastes into construction materials is a potential option for management of high volume wastes. However, due to the high processing costs of the wastes, the conversion may not be economically viable. This study examines the detailed thermochemistry of sludge-clay mixes in providing an in-depth understanding of the reactions involved during the process of fusion. Thermal gravimetric analysis detected increased weight loss of the materials around the temperatures of 520 and 900¢XC, indicating volatilization of organic matter and inorganic salts, at the two respective temperature levels. Differential scanning calorimetry results revealed endothermic reactions, possibly due to dehydroxylation of clay, between temperatures of 480 and 600¢XC, and calcite decomposition between the temperatures of 680 and 900¢XC. Intensified endothermic peaks were observed in the mixes of the two materials. Thermal gravimetric analysis-infrared absorption spectrometry revealed increased intensities of the absorption bands at 1,600cm-1 at 630¢XC and 2,900cm-1 at 710¢XC, as a result of the breakdown of organic matter and alkanes, respectively. Energy demand analysis determined the energy required for raising the temperature of each mix to reach each specific temperature. The intrinsic energy required to raise the firing temperature of the aggregates from 400to900¢XC was determined to be within the range of 20,347 and 38,254kJ/kg, with 100% sludge exhibiting the lowest energy requirement and 20% sludge exhibiting the highest energy requirement. ? 2006 ASCE. |
URI: | https://scholars.lib.ntu.edu.tw/handle/123456789/408032 | ISSN: | 08991561 | DOI: | 10.1061/(ASCE)0899-1561(2006)18:1(55) | SDG/Keyword: | Clay; Differential scanning calorimetry; Hydroxylation; Infrared spectroscopy; Mixing; Phase interfaces; Recycling; Sintering; Sludge disposal; Thermodynamic properties; Thermogravimetric analysis; Presintering phase; Sludge-marine clay mixes; Thermochemical analysis; Aggregates; aggregate; thermochemistry |
Appears in Collections: | 化學工程學系 |
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