過去二十幾年已證實二氧化碳濃度增加之嚴重性，因此，有效捕捉二氧化碳的方法也更加重要。基於環保意識的興起，本研究使用氨水作為吸收劑，模擬從500 MW燃煤電廠捕捉二氧化碳之化學吸收製程，導入分級吸收製程(Staged Absorption)為二氧化碳吸收塔之製程作為基準流程圖，以90%二氧化去除率與氨氣排放濃度10 ppm作為設計規格，調整各個參數，並觀察其變化，找出製程之最小總再生能耗，其參數有:二氧化碳貧液負載(CO2 Lean Loading, mol-CO2/mol-NH3)、氨水之氨濃度(NH3 Concentration, M)和汽提塔操作壓力(Stripper Pressure, atm)等。模擬結果顯示當吸收劑的氨水濃度為3 M，二氧化碳貧液負載為0.26，汽提塔操作在10 atm 時，可得到最佳總能耗3.94 GJ/ton-CO2。得到最佳參數後，利用文獻報導所提到的各種製程，例如:富液分流製程(Rich-split Process)、級間加熱製程(Inter-heating Process)與兩者整合製程(Combined Process)，導入二氧化碳汽提塔製程，探討在何種製程配置條件下可進一步降低能量負擔，並研究其節能機制與原理，最小化稀釋氨水捕獲二氧化碳製程之總能耗。 In the past twenty years, the severity of the increase in CO2 concentration has been proven, so such an effective method to capture CO2 is much more important. Based on the rise of green awareness, this study uses aqueous ammonia as an absorbent to capture CO2 from a 500 MW coal-fired power plant. The base-case process uses the staged absorption process as the CO2 absorbers and the NH3 washing tower. The design targets are 90% CO2 removal and the NH3 emission concentration under 10 ppm by adjusting process parameters, such as CO2 lean loading (mol-CO2/mol-NH3), NH3 concentration (M) and stripper operating pressure (atm) in order to minimize the regeneration energy. The simulation results show that 3 M NH3 concentration of absorbent, 0.26 CO2 lean loading and the CO2 stripper at 10 atm, the minimum of energy consumption can be found as 3.94 GJ/ton-CO2 for base-case process. After that, the advanced stripper processes reported in the literature, for example : the rich-split process, inter-heating process, and combined process are investigated for the energy-saving mechanisms and the minimum of energy consumption can be futher driven to 2.72 GJ/ton-CO2 by the rich-split process.
