改良式電解去離子系統電流提升技術之研究

A Study on the Improvement of Electric Current Efficiency by Modified Electro-deionization System

曲凱樂(Kai-Le Chu)

指導教授 ： 張添晉

國立臺北科技大學/工程學院/環境規劃與管理研究所/碩士(2007年)

摘要

EDI（Electro-deionization）技術，或稱電脫鹽、電解去離子技術，為近年來出現的一項創新之高/超純水製造技術，將傳統電滲析技術和離子交換技術加以結合，既克服電透析不能深度脫鹽的缺點，又彌補離子交換不能連續工作、需消耗酸鹼再生之缺點，此等顯著優勢使得該技術於各個行業得以迅速地被推廣及應用。
電解去離子技術屬一種操作成本昂貴的系統，乃導因於長電導距離及濃度極化現象，即使脫鹽室中已有填充離子交換樹脂來增加水中的導電性，但目前電解去離子技術尚需消耗相當多電力，因此本研究將著重系統中電流效率之改善，以達增加脫鹽效率及降低電量消耗之目的。
本研究利用自行設計之模組，填充增加導電性之物質(如：活性碳)，以不同填充方式，包括：模組中不填充物質、模組脫鹽端填充活性碳、模組脫鹽端填充離子交換樹脂、模組濃縮端填充活性碳及模組脫鹽端填充活性碳加上濃縮端填充離子交換樹脂，在不同電壓下探討其電流提升及脫鹽效果。
利用本研究擬定之二項指標判定實驗結果顯示，模組濃縮端填充活性碳之脫鹽端導電度脫鹽效果為99.7%，而模組無填充則為98.95%，但對於另一指標電流提升兩者卻是相同，顯示以濃縮端填充活性碳之脫鹽效果最佳，但電流未有顯著提升，原因可能為本實驗為批次循環，未能模擬實場上之實際情形，因此將模組濃縮端填充活性碳以連續脫鹽情況下運作，且與模組無填充相比較，得知以連續操7小時作情況下，模組濃縮端填充活性碳之脫鹽效果及電流提升均較模組無填充佳，在脫鹽端導電度以模組濃縮端填充活性碳之30∼31 μs/cm較模組無填充之36∼37 μs/cm來得佳，在電流方面，前者最終電流0.243 A較後者0.137 A高出將近一倍，所以推論此填充方式卻實可有效降低脫鹽端導電度及提升模組電流效果。

關鍵字

EDI ； 電滲析 ； 離子交換樹脂 ； 濃度極化

並列摘要

EDI（Electro-deionization）is an innovation made of ultra pure water technology in present year. It is combined of electro dialysis and ion-exchange technology. Therefore, to overcome the drawback of electro dialysis, deep desalination and make up for ion-exchange technology can not continuously work and need chemicals to regenerate the ion-exchange resin, the superiority of those make this technology to be used more popularly and applied rapidly.
EDI technology belongs to cost expensive operation system, because of long electricity distance and concentrate polarization phenomenon. Even already filled with ion-exchange resins in module to enhance the conductivity, it still consume a lot of energy, consequently, this study is focused to improve the module of electricity efficiency, for the purpose of enhancing the desalination efficiency and reduce the power consumption.
The module in this study is self-designed, filled with materials that could enhance the electric conduction (eg. Active carbon), use different mode of filled, include non filled in the module, filled with ion-exchange resins at dilute compartment in the module, filled with active carbon at concentrate compartment in the module and ion-exchange resins at dilute compartment in the module.
Used two index made by myself during the research to judge the results of this study, one is to observe the electric conductivity efficiency, another is for the promotion of electricity, the results showed the module filled with active carbon at concentrate compartment that electric conductivity is 99.7 %, another non filled in the module is 98.95 %, but the electricity conductivity is the same, the meaning of this is that, the module filled with active carbon at concentrate compartment is superior, but not remarkable for electricity conduction, maybe the reson is the experiment is batch recycle and can not imitate the real case that is continuous process, for this reason, compared with module filled with active carbon at concentrate compartment and non filled in continuous 7 hours operate situation, get module filled with active carbon at concentrate compartment superior to non filled on desalination efficiency and improve electricity efficiency in continuous operate situation, the experiment show the module filled with active carbon at concentrate compartment that electric conductivity 30∼31 μs/cm and better than the module with non filled 36∼37 μs/cm, the final current 0.243 A and 0.137 A respectively, inference that reduce electric conductivity at dilute compartment indeed and improve the electric efficiency.

並列關鍵字

Electro-deionization ； Electrodialysis ； Ion-exchange resin ； Polarization

參考文獻

[4] Allison, R.P., "Electro dialysis reversal in water reuse applications," Desalination vol. 103, 1995, pp.11-18.

[12] Neumeister, Herbert, et al, “Theory and Experiments Involving an Electrodeionization Process for High-Purity Water Production,” Ultrapure Water Journal, April 2000.

[14] Telis Dimitrakopoulos, Emmanuel Feuillas, Daniel Darbouret and Stéphane Mabic, “A publication of the Bioscience Division of Millipore,” American, 1994, pp.10-22

[16] Khimiko-Farmatsevticheskii Zhurnal, "Ultrapure Water Production by Continuous Electrodeionization Method: Technology and Economy," Pharmaceutical Chemistry Journal, vol. 38, no. 1, 2004, pp.35-40

[19] D. Steen and G. De Los Reyes, “Electrically enhanced Mixed-Bed Deionization of Sugars, contrast Agents, and Ureas,” IChE Annual Meeting, Miami Beach, FL, November 4, 1992.