- 學位論文
TFT-LCD 廢玻璃混合轉爐石產製輕質骨材及其特性研究
Manufacturing and Characterization of Lightweight Aggregate from TFT-LCD Waste Glass and Basic Oxygen Furnace Slag
摘要
本研究以薄膜電晶體液晶顯示器(Thin-film transistor Liquid-crystal Display, TFT-LCD)廢素玻璃與煉鋼副產物轉爐石(Basic Oxygen Furnace slag, BOF slag)以實廠規模產製輕質骨材，研析熱處理溫度對輕質骨材物理特性及化學反應特性的影響，以評估利用TFT-LCD廢素玻璃及轉爐石為原料，是否可產出特性優良且符合商用標準之輕質骨材。 試驗結果顯示，隨熱處理溫度的增加，試體黏滯性玻璃包覆相的黏度將隨之降低，使玻璃化程度越趨完全。當輕質骨材玻璃化程度越高，其吸水率、體密度及容積密度則愈低。筒壓強度呈現先上升後下降之趨勢，當熱處理溫度介於1000°C－1020°C，隨著骨材表面玻璃化程度愈高，筒壓強度則愈高；當熱處理溫度高於1020°C，因孔隙增加及表面開始產生微孔隙，故輕質骨材可承受之強度開始下降。晶相析出量與種類隨著熱處理溫度增加而漸增，能使轉爐石中的游離氧化鈣與其他物質形成鈣長石(Al2CaSi2O8)、頑火輝石((Ca,Mg,Fe)Si2O6)、矽灰石(CaSiO3)與透輝石(CaMgSi2O6)之結晶相，可有效固定並降低73.11%的游離氧化鈣含量。經骨材冷卻段之晶相探討，當後段持溫溫度高於800°C以上時，則具有鹼矽反應(Alkali-silica reaction)特性之方石英(Cristobalite)晶相將隨持溫溫度及時間的增加而大量析出。如欲將產出之輕質骨材應用於輕質混凝土，於冷卻階段應將溫度迅速降低至800°C以下，避免產出方石英影響混凝土試體之耐久性。本研究所產出之輕質骨材，經鹼矽反應性試驗證實屬不具危害性(Innocuous)之骨材，且適用於結構用輕質骨材。當熱處理溫度為1030°C所產出之輕質骨材，體密度為1.37 g/cm3、容積密度為851.96 kg/m3、吸水率為1.12%及筒壓強度為11.98 MPa，除符合輕質骨材之商用規範外，更具有較低吸水率之優勢。 本研究以TFT-LCD廢玻璃混合煉鋼副產物轉爐石，利用圓盤造粒機及旋轉式窯爐成功產製出物理特性與化學反應特性符合商用規範之輕質骨材，並能有效降低游離氧化鈣含量。
並列摘要
The aim of this study was to manufacture the lightweight aggregate (LWA) from a mixture of thin film transistor liquid crystal display (TFT-LCD) waste glass and basic oxygen furnace (BOF) slag in the field prototype scale. Pellets were produced by pelletization then, rapidly sintered and bloated at the temperature between 1000°C and 1040°C by rotary kiln. The effects of thermal treatment condition on the physical and chemical properties of LWA were investigated. Experimental results indicated that the vetrification of the surface of LWA led to improve its cylindrical compressive strength and lower its water absorption. In addition, the degree of vitrification was increased with temperature increase. The content of free-CaO in LWA was decreased significantly, because the crystallinity of crystalline phase which contained Ca element were increased. LWA was considered innocuous according to the experiment of alkali-silica reaction which included accelerated mortar bar test (ASTM C1260) and the rapid chemical test (ASTM C289). In conclusion, the physical and chemical properties of the LWA which was made of TFT-LCD waste glass and BOF slag complied with the specifications of commercial lightweight aggregate. Therefore, it could be used in the production of the structural lightweight concrete.