本研究為探討奈米級零價鐵結合二氧化碳曝氣系統對水中硝酸鹽之去除效果，研究之控制參數包括不同之起始pH値(4、6、8、10)、不同零價鐵劑量(0.25 g、0.5 g)、硝酸鹽起始濃度(50、100、200 mg/L)與不同曝氣條件(N2、CO2)等，並且在系統操作過程中即時監測pH、 DO、ORP等指標，探討使用化學程序，以奈米級零價鐵結合二氧化碳曝氣系統去除水中硝酸鹽離子之成效。
在實驗結果顯示，零價鐵去除水中硝酸鹽反應中，硝酸鹽起始濃度為100 mg/L，零價鐵劑量為0.25 g、0.5 g，不曝氣之條件下，硝酸鹽去除率分別為15 %、38 %，此表示增加零價鐵劑量有助於硝酸鹽去除效果。在控制起始pH値為4、6、8、10，結果發現系統pH値在6、8、10時有較佳硝酸鹽去除率；且於使用二氧化碳及氮氣進行先期除氧並配合不同CO2曝氣反應過程中，發現使用氮氣先期去氧此方法較二氧化碳曝氣系統有較佳之去除效果。 In this study, the Fe0/CO2 process was investigated for removing nitrate from aqueous solution under different operating conditions such as initial pH(4、6、8、10)、Fe0 dosage (0.25、0.5), initial nitrate concentration (50、100、200 mg/L) and different aeration gase on the removal of nitrate from aqueous solution by chemical reduction. The solution pH, ORP, DO, were also monitored in order to get the best conditions for nitrate remediation. This experiment is try to removed aqueous nitrate by nFe0 coupled with dioxide bubble in physical way.
The results shows that the removals of aqueous nitrate reduced by NZVI under initial NO3- concerntation at 100 mg/L, Fe0 dosage at 0.25 g、0.5 g conditions were 15% and 38%, respectively. The result indicated that the higer Fe0 dosage, the lower will be the residue nitrate. At initial pH 6,8 and10 the removals of NO3- almost the same . However, when solution initial pH at 4 a lower removal of NO3- was observed. The nitrogen gas used to purge dissolved oxygen is better in terms of NO3- removal than using CO2.
