臺灣博碩士論文加值系統

台灣地區之水源已普遍遭受有機物污染， 此有機物的存在會影響淨水處理中之加氯消毒程序，因此如何去除飲水中微量有機物為當務之急的工作。傳統之淨化程序，並無法有效去除飲水中之微量有機物。高級淨水程序因而被發展、應用，以確保飲水之安全，其中以活性碳吸附飲用水中之有機物，乃目前台灣地區淨水程序中，最廣泛被採用的方法之一。本研究之目的乃針對活性碳去除飲用水中微量有機物，建立活性碳迷你管柱吸附模式，其包含簡易模式、表面擴散模式及孔隙 - 表面擴散模式。 探討活性碳用量、水樣流量、擴散性質等對活性碳吸附量之影響。研究方法為利用有限差分方法將微量有機物於活性碳迷你管柱中傳輸之質傳方程式，重新改寫為一階聯立微分方程式，然後以 Runge-Kutta fourth-order method 加以求解。 在與實驗室中迷你管柱實驗之結果相較，校正模式之參數。以推求最佳孔隙表面擴散係數、孔隙擴散係數、介面膜傳輸係數及等溫吸附曲線常數。 經由一連串的模擬結果可知，迷你管柱吸附之孔隙 - 表面擴散模式為預測迷你管柱實驗之較佳模式。由相關參數之靈敏度分析，可知孔隙擴散效應較表面擴散效應為重要，在迷你管柱內，微量有機物輸送之驅動力並非管柱擴散效應而是管柱內之壓力降。應用模式探討流量、活性碳用量、初始濃度及管徑大小等操作條件所得之貫穿曲線與實際實驗所得貫穿曲線之趨勢吻合，故應用模式之結果可以做為實驗室實驗設計之參考，並可作為實廠設計和操作之依據。

Most of Taiwan''s water resources are polluted by organic matter which,disrupts the chlorination process in water treatment. Logically, the removalof trace organic matter from drinking water is a very important work sincetraditional water treatment processes do not effectively remove the traceorganic matter from drinking water. Advanced water treatment processes,including the most frequently used carbon adsorption process, were developedto supply safe drinking water. The purpose of this study is to developmini-column adsorption models such as the simple, surface diffusion andpore-surface diffusion models, for the removal of trace organic matter indrinking water by activated carbon. The effect of dosage, flow flux anddiffusion properties on adsorption capacity will be explored. The finitedifference method will be used to rewrite the transport control equationinto a system of first-order differential equations, which would then besolved by the Runge-Kutta fou rth-order method. Simulation results arecompared to those of rapid small scale column tests ( RSSCT ) fromlaboratory. The best fitted values for surface diffusion coefficients, porediffusion coefficients, interfacial transport coefficients and isothermadsorption constants are obtained by calibrating the models to experimentaldata. From a series of simulation runs, we observe that the pore-surfacediffusion model is the best among these three models developed in this studyfor predicting the behavior of RSSCT. The effect of the pore diffusion isdetermined to be more important than that of surface diffusion by usingsensitive analysis on relational parameters of the pore-surface diffusionmodel. The driving force that transported trace organic matter is thepressure drop instead of the diffusion in the mini-column. Operationvariables including flow rate, GAC dosage, initial concentration and thecolumn size are explored. Breakthrough curves obtained from theaforementioned models are compared with actual experimental datasatisfactorily. These models can serve as a guide to design experiments andto estimate pertinent parameters. They can also be used to predict andevaluate the performance of an adsorption column as well as optimize itsperformance.