以石化廠副產石灰進行超重力碳酸化程序固化二氧化碳與 取代水泥

Abstract

近年來，全球的氣候受到溫室效應的影響而造成全球暖化，二氧化碳的排 放管制及減量技術也受到重視，本研究試以石化工業高溫循環式流體化床鍋爐 (Circulating Fluidized Bed Boiler，簡稱 CFB)所產出的副產石灰（粉狀飛灰）之 鹼性廢棄物通過超重力旋轉床（RPB）進行碳酸化程序，來達到固存二氧化碳。 其中超重力旋轉床的轉速（550-950rpm）、飛灰與水的固液比（15-35 ml/g）、反應槽溫度（20-60 oC）為非常重要的參數，改變這些參數來探討對轉 換率的影響，研究中將嘗試找出碳酸化程序最佳參數。反應後的產物將會做熱 重分析儀（TGA）進行定量分析，再使用掃描式電子顯微鏡（SEM）進行定性分 析。而反應後之副產石灰加入水泥進行取代的可行性評估，為了確保副產石灰 的加入不會造成結構上及化學上的破壞，故必須對水泥砂漿體進行稠度試驗、 流度試驗、凝結時間試驗、蒸壓膨脹試驗、乾縮試驗、抗壓強度試驗等力學測 試。結果顯示反應後的副產石灰確實優於未反應的副產石灰，故本研究在固存 二氧化碳及減少水泥用量減少能量耗損上是可行的。

For the past few years, the climate has been greatly influenced by greenhouse effects, which is also the main factor that causes global warming. In addition, the emission control and the regulation technology of carbon dioxide has been getting more and more attention in the research community. The study of carbonated alkaline waste of By-product lime (fly ash) produced by Circulating Fluidized Bed Boiler (so called CFB) in Petrochemical Industry is used to fixate the carbon dioxide. Furthermore, the study tries to find the best parameters in the carbonation process through changing parameters to investigate the effect of conversion, among which rotation speed of Rotating Packed Bed (550-950rpm), tank temperature (20-60 oC) and Solid-liquid ratio of water and fly ash (15-35 ml/g) are the most important parameters. The carbonated CFB fly ash will not only be analyzed quantitatively by Thermogravimetric analysis, but also analyzed qualitatively by Energy Dispersive X-ray Spectroscope; moreover, we add Portland cement to make a replaceable feasibility assessment regarding whether the CFB fly ash is fresh or carbonated. For the purpose of assuring added CFB fly ash will not cause chemical and structural destruction, we have to take Normal Consistency, Flow Test, Setting Time, Autoclave Expansion, Drying Shrinkage, Compressive Strength in account for the Cement mortars. The study result shows that the carbonated CFB fly ash is definitely better than fresh CFB fly ash, as it is available to fixate carbon dioxide and reduce the quantity of cement to regulate energy dissipation.