以田口方法研究煤炭及焦炭-瀝青燒結之最佳條件

OPTIMIZATION OF SINTERING PARAMETERS FOR COAL AND COKE-CTP BY TAGUCHI METHOD

辛昱霖(Yu-Lin Hsin)

指導教授 ： 林永仁

大同大學/工程學院/材料工程學系所/碩士(2010年)

摘要

本研究分別以煤炭(Coal)及焦炭-瀝青(Coke-CTP)進行熱壓和燒結，應用田口方法找出其最佳製程參數，並進行熱學性質及機械性質之分析。煤炭內因含有有機物，故須先經前處理後，將煤炭內的部分有機物或氣體先除去，再進行熱壓及燒結；而焦炭添加瀝青則因在常溫下無法成形，故須先經熱壓成形後，再進行燒結。
以田口方法分析出煤炭的製程參數中以燒結溫度為最重要，前處理溫度次之。前處理溫度以300°C為最佳，而試片隨著燒結溫度的增加，其體密度和強度值隨之上升，開孔隙率則相反，且在燒結溫度1200°C時，試片的線收縮率約為21%，體密度達1.56 g/cm3，且試片的等向雙軸彎曲強度(equi-biaxial flexural strength, or ring-on-ring flexural strength)可達27.8 MPa；而焦炭添加瀝青的試片，則以瀝青添加量為最重要製程參數，添加量以25wt%為最佳，且試片在燒結溫度為700°C時，體密度為最高，可達1.34 g/cm3，開孔隙率為最低，試片的等向雙軸彎曲強度(equi-biaxial flexural strength)為13.4 MPa。煤炭及焦炭-瀝青試片其組成結構不僅為微晶石墨，且存在非晶質石墨結構，代表兩者內部結構仍具有許多的缺陷。

關鍵字

熱學性質 ； 燒結 ； 瀝青 ； 焦炭 ； 煤炭

並列摘要

Coal powder and coke-pitch mixtures were processed to form pellets and their microstructures and strengths were investigated. Coal powder was preheated to eliminate parts of volatile substance. Coke and pitch powders were dry-mixed. Both pre-heated coal powder and coke-pitch mixtures were hot-pressed and then, sintered to form bulk pellets. The optimal combinations of processing parameters (pre-treatment temperature, sintering temperature, pitch amounts, etc) were obtained for high bulk density by Taguchi method.
The results showed that for coal powder, sintering temperature was the most influential processing parameter and pre-treatment temperature was another. The best pre-treatment temperature for coal powder was 300°C. The bulk density and the equi-biaxial (or ring-on-ring) flexural strengths of the pellets increased with sintering temperature. The highest density and strength obtained were 1.56 g/cm3 and 27.8 MPa, respectively, after the pellets were sintered at 1200°C. For coke-pitch pellets, the amount of pitch was the most influential processing parameter. The best amount of pitch was 25wt%. When coke-25% pitch pellets were sintered at 700°C, its bulk density was 1.34 g/cm3 and equi-biaxial flexural strengths reached 13.4 MPa. For both kinds of pellets, their microstructures consisted of amorphous graphite as well as micro-crystalline graphite, indicating many defects existed in the structures.

並列關鍵字

sintering ； pitch ； coke ； coal ； thermal behavior

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