高溫零價鐵流體化床併同處理氮氧化物/硫氧化物之研究

Simultaneous removal of nitrogen monoxide and sulfur dioxide by high temperature fluidized zero valent iron processes

韋忠誠(Chung-Cheng Wei)

指導教授 ： 陳孝行

國立臺北科技大學/工程學院/環境規劃與管理研究所/碩士(2006年)

摘要

本研究係以實驗室之流體化床管柱定溫反應實驗，探求零價鐵(zero valent iron, ZVI) 併同處理空氣污染物一氧化氮(NO)、二氧化硫(SO2)之可行性研究，藉改變三種操作參數，包括反應溫度（573 K、623 K、673 K、723 K、773 K）、流通量（0.5、0.6、0.7、0.8 L/cm2•min）、鐵粉量（0.25 g、0.5 g、0.75 g、1.0 g）等，探討其對一氧化氮、二氧化硫去除之影響。
從不同反應溫度實驗可知，在NO、SO2進流濃度為500 ppm，鐵粉量為0.5 g，流通量為0.6 L/cm2•min時，反應溫度573 K無任何的NO、SO2累積去除量。在623 K、673 K 時，NO去除率可達100％，而SO2的去除率可達90％以上。於723 K、773 K時，則NO、SO2的去除率均可達100％。而623 K、673 K、723 K、773 K之單位鐵粉去除NO、SO2能力分別為6.33、22.65、46.28、57.52 mg NO/g Fe；11.43、30.03、65.55、109.47 mg SO2/g Fe，顯示單位鐵粉的NO、SO2去除量隨反應溫度增加而增加，且兩者均為迴歸係數大於0.97的線性關係。而SO2與NO比較時，因SO2擴散速率較慢及分子量較大，使得其穿透時間較短及累積去除量較多之情形。
NO、SO2累積去除量隨鐵粉量增加而增加，但與流通量無明顯的關聯性。NO、SO2穿透時間會受鐵粉量及流通量所影響。而鐵粉重量/流通量(WFe/F)比與NO、SO2穿透時間呈現線性正相關，可用來預測NO、SO2穿透時間。
零價鐵併同處理NO、SO2，因氧化程序及還原程序同時發生，使得NO、SO2穿透時間及單位鐵粉NO、SO2去除量均較僅行還原程序的零價鐵單獨處理NO、SO2效果佳，可由反應後的鐵粉XRD圖獲得證明。

關鍵字

零價鐵 ； 一氧化氮 ； 二氧化硫 ； 流體化床 ； 併同處理

並列摘要

A new research to simultaneously remove of nitrogen monoxide (NO) and sulfur dioxide (SO2) by zero valent iron (ZVI) was conducted. Three different parameters : temperature (623 K, 673 K, 723 K and 773 K), flux (0.5, 0.6, 0.7, 0.8 L/cm2．min) and ZVI dosages (0.25, 0.5, 0.75 g and 1.0 g) were tested in fluidized column studies containing 500 ppm of NO and SO2.
Under the ZVI dosages of 0.5 g at flux 0.6 L/cm2．min for temperature 573 K, there is no either NO and SO2. For 623 K and 673 K, complete removal for NO and more than 90% removal for SO2 were achieved. For temperatures of 723 K and 773K, 100 % removal was achieved for both NO and SO2.When the temperature was controlled at 623 K, 673 K, 723 K and 773 K, the NO reduction were 6.33, 22.65, 46.28, 57.52 mg NO/g ZVI and the SO2 reduction were 11.43, 30.03, 65.55, 109.47 mg SO2/g ZVI. The result indicate that the amounts of NO or SO2 reduction (as mg NO or SO2/g ZVI) increased as temperature increased, and linearities were found with both correlation coefficients >0.97.Comparing to NO, SO2 had earlier breakthrough due to slower diffusion rate and less reactivity, but higher mass reduction due to higher molecular weight for SO2 (64 Da for SO2 and 28 Da for NO ) from the calculation equation of mass reduction based on ideal gas law.
The mass reduction of NO and SO2 were higher with the increasing of ZVI dosage. But these were constant regardless of flux variation.The breakthrough time was affected by both flux variation and ZVI dosage. A parameter ZVI weight/flux (W/F) was developed to assess the breakthrough time of NO and SO2 removed by ZVI and higher breakthrough time can be achieved for higher W/F value.
The longer breakthrough time and more NO and SO2 reduction were achieved for combined NO and SO2 than individual NO or SO2 treated by ZVI, ascribing to both oxidation and reduction reaction were occurred instead of reduction reaction only. Chemical reactions among ZVI/NO, ZVI/SO2 and ZVI/NO/SO2 were proposed and verified by XRD analyses.

並列關鍵字

zero valent iron ； nitrogen monoxide ； sulfur dioxide ； fluidized column.XRD

參考文獻

[6] 黃揚舜，零價鐵填充床及流體化床處理二氧化硫之研究，碩士論文，國立臺北科技大學環境規劃與管理研究所，臺北，2005。

[7] 黃其聰，醇類燃料對汽油引擎排氣分析研究，碩士論文，中原大學機械工程學系，桃園，2004。

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