臺灣博碩士論文加值系統

本研究分為三部分進行:氫氧化鈣/飛灰製備與特性探討,單一SO2氣體去除實驗及SO2和NO同時去除實驗. 在酸性氣體去除實驗中,主要探討之操作參數為當量比值(SR)和趨近絕熱飽和溫度(AT). 研究結果顯示,氫氧化鈣/飛灰確時比氫氧化鈣擁有較大的比表面積,孔隙體積和平均孔隙直徑,並且提高SO2和NO去除效率. 酸性氣體去除實驗結果顯示,當趨近絕熱飽和溫度(AT)愈低或當量比值(SR)愈高時,吸附(收)劑對酸性氣體的去除效率也愈高. 在單一SO2氣體去除時,以添加CaCl2.2H2O的效果最好,海水次之,而以NaCl最差. 在SO2及NO氣體同時去除時,SO2去除效率比單一氣體去除時略高,而添加物之除酸效率高低順序與單一氣體存在時完全相同. 對NO去除效率之提昇而言以NaOH最有效,其次為海水,而以CaCl2.2H2O最低,此結果說明鹼度對NO去除效率之提昇,具有相當大的幫助.

This study investigated the removal of acidic gases(SO2 and NOx) from flue gas using a dry sorbent injection duct reactor which was originally designfor this study to increase the removal efficiencies of SO2 and NOx. High reactive sorbents were prepared by adding fly ash to Ca(OH)2. Furthermore, inorganic additives including NaCl, NaOH, CaCl2.2H2O, and sea water were added intoCa(OH)2/fly ash to enhance the removal efficiencies of acidic gases. Thisstudy consisted of three parts : the preparation and characterization of Ca(OH)2/fly ash, the removal of SO2, and the simultaneous removal of SO2 and NO. Major operating parameters investigated in the acid gas removal efficiency tests were stoichiometric ratio(SR) and approach to adiabatic saturation temperature(AT). Experimental results indicated that Ca(OH)2/fly ash had higherspecific surface area, pore volume, and average pore diameter than original Ca(OH)2, which could increase the removal efficiencies of SO2 and NO. Duing the slurrying reaction of higher temperature, Ca(OH)2 and fly ash would react and form CaSiO4, which resulted in a higher specific surface area.Such experimental results further agreed with the change of sorbents'surface observedfrom SEM photograph. Experimental results obtained from the acid gas removal efficiency tests indicated that higher removal efficiencies of acidicgases could be achieved at a higher stoichiometric ratio or a lower approach to adiabatic saturation temperature. For the removal of SO2,CaCl2.2H2O was the most effective,sea water was the second effective, and NaCl was the least effective additive to enhance the removal efficiency of SO2. This study also revealed that the amount of water influenced the reaction between SO2 and sorbents much more than alkalinity. In the simultaneous removal tests of SO2 and NO,the removal efficiency of SO2 was higher than of SO2 in the single gas removalefficiency test,and the effect of inorganic additive was the same as they werein the experiment of SO2 removal efficiency tests. In addition, NaOH was the most effective, sea water was the second effective,and CaCl2.2H2O was the least effective additive to increase the removal efficiency of NO. It showed that alkalinity played an important role on increasing the removal efficiency of NO.