界面型太陽能蒸餾系統應用於潔淨水生產之研究

Clean Water Generation Through Interfacial Solar Distillation

陳冠宇(Kuan-Yu Chen)

指導教授 ： 林郁真

國立臺灣大學/工學院/環境工程學研究所/碩士(2019年)

https://doi.org/10.6342/NTU201901704

摘要

由於人類社會的快速發展，全球氣候變遷和人口增長導致了水資源在質跟量方面的衰退，替代性水資源的開發正如火如荼的展開；然而，現行的海水淡化或是水回收技術需要耗費大量能源，而這對一些缺乏能源基礎建設的地區是相當大的挑戰，因此發展低能耗、高產量的潔淨水生產技術是勢在必行的。利用浮於界面的光熱轉換層促進太陽能蒸餾水為一具發展性的潔淨水生產技術。在本研究中，我們製作了一具雙重功能的界面蒸發裝置；此裝置除了擁有高的蒸氣產生效率之外，更能夠有效防止揮發性有機物（酚）被一同蒸發進入乾淨的蒸餾水。我們以混合了二氧化鈦光觸媒的活性碳作為光熱轉換層，而以聚乙烯泡棉作為此界面裝置的支撐層。由於活性碳良好的吸光度，再加上聚乙烯泡棉除了賦予裝置浮於界面的能力外，更透過熱區域化的方式進一步提升裝置的蒸氣產生表現，其蒸氣產生速率分別為無裝置時和傳統蒸發系統（沉浸於水溶液底部的二氧化鈦活性碳）的3倍以及1.7倍。除了界面蒸發優異的蒸氣產生表現外，本研究亦證明界面蒸發系統不易受水中懸浮固體的影響，其原因為透過於界面吸光，能夠避免因懸浮固體所導致的光散射而造成入射光強度減少的問題。本實驗中也利用合成鹽水（3.5% (w/v)的氯化鈉溶液）進行潔淨水生產的展示；透過界面蒸發，在蒸餾水中僅能發現低濃度的氯離子，且相較於無蒸發裝置的系統，界面蒸發系統有更高的蒸餾水產量。除此之外，此界面蒸發裝置能夠有效避免水中的酚在太陽能蒸餾過程中與水一起蒸發並收集至蒸餾水中；主要原因是由於酚在通過界面蒸發裝置時將受裝置上的活性碳吸附及二氧化鈦光催化反應而使其降解。應用界面蒸發在太陽能蒸餾程序，不僅能有更高的蒸餾水產量，其產生的蒸餾水也有更好的水質，顯示界面蒸發輔助太陽能蒸餾作為潔淨水生產程序的潛力。

關鍵字

光熱轉換 ； 光催化 ； 界面蒸發 ； 太陽能蒸餾

並列摘要

Due to the rapid development of human society, freshwater resources have degraded in both quantity and quality. The exploitation of alternative water resources, such as seawater and wastewater is imperative. However, current techniques for desalination and water reuse have the disadvantage of high energy consumption, which could inhibit development in areas lacking energy infrastructures. Therefore, developing clean water generation techniques with low energy consumption and high efficiency is necessary. Interfacial solar distillation systems assisted by floating photothermal layers are a promising method for clean water generation. In this study, a bifunctional interfacial evaporation device with high steam generation efficiency and rejection ability of phenol in distilled water was established. Activated carbon (AC) blended with commercially available TiO2 (AC-P25) served as the photothermal layer, and polyethylene foam (PE foam) was used as the supporting layer. The excellent optical absorbance of AC and the heat localization effect caused by PE foam promoted the steam generation performance by increasing the evaporation rate 3 and 1.7 times, compared with the water-only and the conventional evaporation (i.e., submerged AC-P25) systems, respectively. In addition to the superior steam generation performance, interfacial evaporation was proven to be less affected by suspended solids in water by reducing the influence of the light scattering effect. Clean water generation was demonstrated using synthetic saline water (3.5% (w/v) NaCl(aq)), and good salt rejection and high water productivity were achieved through interfacial evaporation. Additionally, phenol enrichment during solar distillation was successfully prevented with the use of AC-P25/foam through adsorption and photocatalytic degradation. The high distilled water productivity and good distilled water quality indicated the potential of interfacial solar distillation in clean water generation.

並列關鍵字

photothermal conversion ； photocatalysis ； interfacial evaporation ； solar distillation

參考文獻

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