- 學位論文
生化需氧量感測系統之研發
Development of a Biochemical Oxygen Demand Sensing System
摘要
本研究是利用三極式電化學偵測器、活性污泥菌種及流動注射分析系統建立一生化需氧量（BOD）的感測系統，並針對實際廢水作生化需氧量的檢測。 感測器採用白金工作電極及Ag/AgCl參考電極，白金工作電極表面修飾有20μL的Nafion薄膜，以減少雜訊。反應區域採用壓克力材質，活性污泥置於其中心一18 mm (L) ´ 2 mm (W) ´ 2 mm (D)的凹槽，利用上述電極及流動注射分析系統針對樣品作反應與檢測。分別建立以人工廢水GGA（Glucose-glutamic acid）及豬糞尿廢水為樣本的標準曲線，從輸出的電流與時間的關係圖，利用終點法（End point）、固定時間法（Constant time）、斜率法I（Quasi-kinetic I）及斜率法II（Quasi-kinetic II）等四種方式推估BOD的濃度。 利用現場取樣的豬糞尿廢水作測試以驗證本系統之準確度，結果顯示採用GGA建立的標準曲線所測得的BOD濃度，以固定時間法以及斜率法I的結果較佳，其檢測的誤差分別為8.96%以及7.65%。而採用豬糞尿廢水建立的標準曲線所測得的BOD濃度，終點法、固定時間法以及斜率法I可以更準確地預估實際廢水之BOD值，其誤差分別為0.81%、2.49 %及1.69 %。
並列摘要
A biochemical oxygen demand (BOD) sensing system was developed using the combination of three-electrode electrochemical detector, seed from active sludge, and flow injection analysis system (FIA) in this study to examine the BOD of wastewater. The detector contained an Ag/AgCl electrode (reference electrode, RE) and a Pt electrode (working electrode, WE), which was coated with 20mL Nafion to reduce noises. The reactor was fabricated with acrylic plastic, and the seed of activated sludge was placed in an 18 mm (L) ´ 2 mm (W) ´ 2 mm (D) cave, in which the tested sample was reacted and detected with the above electrodes through the flow injection analysis system. Standard curves were built from the experimental data for both GGA (glucose-glutamic acid) synthetic wastewater and swine wastewater by different approaches: end-point, constant-time, quasi-kinetic I, and quasi-kinetic II, respectively. To verify the effect of this system, wastewater from pig farm were tested. The results showed that, when using the standard curves generated by GGA wastewater, the constant-time and quasi-kinetic I had better performance in estimating the BOD concentration, with the deviations of 8.96% and 7.65%, respectively. In addition, when using the standard curves generated by the swine wastewater, the end-point, constant-time and quasi-kinetic I had much better estimate than the above, with the deviations of 0.81%, 2.49%, and 1.69%, respectively.