活性碳等溫吸附與吸附床設計應用於血液透析用水中餘氯移除之探討

The granular activated carbon adsorption isothermal and adsorption bed design application to remove chlorine in hemodialysis Water

王子達(Zhi-Da Wang)

指導教授 ： 張炎林

中原大學/工學院/生物醫學工程研究所/碩士(2011年)

https://doi.org/10.6840/cycu201101117

摘要

中文摘要

水中餘氯/氯胺之殘留對於血液透析病患而言有相當的威脅性，根據相關文獻指出水中餘氯/氯胺的存在與透析病患於治療期間產生溶血現象有相關性。另外，在所有透析用水處理程序當中唯有活性碳吸附程序可有效移除水中餘氯/氯胺以降低透析病患溶血現象之發生。本研究目的為透過等溫吸附以及固定床吸附理論之數學模式預估活性碳吸附床之穿透時間及填充高度，以有效達到水中餘氯/氯胺之移除，降低透析病患透析期間溶血現象之發生。
本研究利用臨床單位使用之活性碳吸附劑進行三類試驗，第一類為以固定質量之活性碳進行吸附速度試驗；第二類為取不同質量活性碳分別於定容之次氯酸鈉溶液中進行等溫吸附試驗，並將吸附結果以回歸分析及相關分析找出適合之等溫吸附模式；第三類則為根據臨床單位之碳吸附裝置規格比例縮小後進行固定床模擬吸附試驗，並將吸附結果以固定床吸附數學理論模式進行分析。
本研究結果發現臨床單位使用之活性吸附劑能有效於5分鐘內將水中餘氯/氯胺降低，於15分鐘完全移除。將等溫吸附試驗結果以回歸分析發現臨床使用之活性碳吸附劑為有利吸附，該吸附指數(1/n)為0.52；比較Langmuir與Freundlich之相關分析結果發現該吸附劑較符合Freundlich等溫吸附模式，該相關係數為0.91。固定床吸附模擬試驗結果得到管柱吸附之穿透時間為13小時，飽和吸附時間為21小時，利用固定床吸附理論數學模式計算得管柱吸附帶(δ)為0.02公尺、管柱吸附帶移動速度(ν)為3.04 x 10-3(公尺/小時)、移動單位數(Nf)為3.61以及總容量數(Kfav)為9925.23(1/小時)，設定不同理論溶液濃度帶入理論數學模式中計算得該模式之理論吸附時間與試驗時間有良好之相關性。隨後，將臨床單位碳吸附裝置相關參數帶入理論數學模式中得規模放大之理論填充床高度(Z)為0.87公尺與製造商提供之填充床高度1公尺相比誤差為0.13公尺，理論穿透時間計算為8760小時與廠商建議之更換時間相符。透過等溫吸附試驗及固定床吸附理論數學模式，可預估活性碳填充床預定之穿透時間及填充高度，以達到有效移除水中餘氯/氯胺，以降低透析病患於透析期間溶血現象之發生。

關鍵字

氯胺 ； 氯 ； 碳 ； 吸附 ； 水處理 ； 血液透析

並列摘要

Abstract

Chlorine/chloramine residues in water have a considerable threat to hemodialysis patients. According to relevant literature, chlorine/chloramine residues in water are related to the hemolysis phenomenon during the treatment of dialysis patients. In addition, among all the water treatment procedures of dialysis, only the activated carbon adsorption procedure can effectively eliminate chlorine/chloramine residues in water to reduce the hemolysis phenomenon of dialysis patients. The purpose of this study is to estimate the breakthrough time and filling height of the activated carbon adsorption bed by the mathematical models of the isotherm adsorption and fixed bed adsorption theories, in order to effectively remove the chlorine/chloramine residues in water and reduce the occurrence of hemolysis phenomenon of the dialysis patients during dialysis.
This study conducted three types of tests using the clinically used activated carbon adsorbents. The first type test was the adsorption speed test using a fixed amount of activated carbon; the secondary test was the isotherm adsorption test of using different amounts of activated carbon in sodium hypochlorite solution of given volume, and conducted regression analysis and relevant analysis of the adsorption results to find the appropriate isotherm adsorption model; the third type of test was the fixed bed adsorption simulation test with carbon adsorption device of scaled dwon specifications for clinical use, and the adsorption results were analyzed using the fixed bed adsorption mathematical theoretical model.
The results suggested that the clinically used activated adsorbents can effectively reduce the chlorine/chloramine residues in water in 5 min, and completely eliminate them in 15 min. The regression analysis of the isotherm adsorption testing results found that the clinically used activated carbon adsorbent can facilitate adsorption with the adsorption index (1/n) at 0.52. A comparison with the relevant analysis results of Langmuir and Freundlich found that the adsorbent can better fit the Freundlich isotherm adsorption model with correlation coefficient at 0.91. The fixed bed adsorption simulation results suggested that the breakthrough time of the column adsorption were 13 hr and the saturated adsorption time was 21 hr. By the mathematical model of the fixed bed adsorption theory, the column adsorption belt (δ) was 0.02 m, and the column adsorption belt moving speed (ν) was 3.04 x 10-3(m/hr), number of moving units (Nf) was 3.61 and the total capacity (Kfav) was 9925.23(1/hr). By inputting different theoretical solution concentrations into the theoretical mathematical model, it was confirmed by calculation that the theoretical adsorption time and testing time of the model have good correlation. The relevant parameters of the clinically used carbon adsorption device were input into the theoretical mathematical model to obtain the theoretical filling bed height (Z) of theoretical scaling up as 0.87 m, which was a gap of 0.13 m from the filling height bed height of 1 m, as provided by the manufacturer. The theoretical breakthrough time was 8760 hr, which was consistent with the manufacturer-suggested replacement time. By isotherm adsorption test and the fixed bed adsorption theoretical mathematical model, the breakthrough time and filling height of the activated carbon filling bed can be estimated to effectively eliminate the chlorine/chloramine residues in water to reduce the occurrence of hemolysis phenomenon of dialysis patients during dialysis.

並列關鍵字

chloramine ； chlorine ； carbon ； adsorption ； water treatment ； hemodialysis

參考文獻

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