台灣地區天然條件豐富,因而產生豐富溫泉資源。溫泉資源種類繁多且不一,大致上可分為以碳酸根離子為主的碳酸氫泉、以硫酸根離子為主的硫酸鹽泉,其中又以碳酸根離子為主的碳酸氫鹽泉為台灣主要之溫泉泉質。在溫泉水進行運輸之過程中,由於溫泉水富含礦物質容易造成溫泉管線及儲存設施產生結垢情形,若不予理會,即可能導致管線爆裂、腐蝕、管線棄置及泉質惡化等相關問題產生,造成多餘人力資源上的浪費以及增加額外的營運成本。目前最常見的處理方式為添加複磷酸鹽類作為清除管線中結垢之化學添加劑,由於其成分中含有氮、磷等成分在,一旦排入河川水體,亦造成河川水體中二次污染(優養化),造成水體額外負擔,影響生態平衡。
本研究著重環境永續發展理念,以物理性方式處理溫泉管線結垢問題,利用磁能技術所產生之物理磁化效應,在不同反應條件下,設計一系列相關之參數進行可行性探討。實驗設計以人工調配模擬溫泉水樣(含有過飽和之鈣離子及碳酸氫根離子),設定不同溫度及流速下,運用磁能換能器進行實驗並觀察水樣中pH值變化,作為判斷在不同參數條件設定下是否產生結垢之依據,並將在實驗反應之前後之水樣進行鈣離子濃度分析,探討該技術於溫泉抑制結垢物生成層面之效果。
研究結果顯示,磁能換能器技術適合在低溫及低流速情形下為最佳,其磁化效應可增加水樣中陰陽離子界面電位增加,形成一短暫性電子包覆團,造成陰陽離子因電位增加而產生互斥現象,降低水樣中陰陽離子結合機率,產生固體性顆粒(CaCO3)生成之抑制。然而,在高溫及高流速下所產生之抑制效果較不明顯,此項結論仍須持續進行相關研究及探討。 Formation of scale deposits in pipelines by natural waters is one of the major problems in the hot spring industry. Economical and technical difficulties are encountered due to the damage in pipes and storage equipment caused by calcium carbonate deposition. Various chemical treatments have been applied to decrease scaling such as addition of soda ash, application of scaling inhibitors, or use of ion exchange resin to replace calcium with soluble ions. These methods prove to be effective in controlling scale formation. However, these treatments remain expensive and can cause changes in the composition of natural waters.
The present study aims to investigate the influence of the magnetic effect on calcium carbonate precipitation from synthetic hot spring water. The effect of varying different operating parameters such as flow rate (0.5 L/min and 1.0 L/min), initial [HCO3-]/[Ca+2] concentration (1.0 and 5.0), and temperature (250C and 450C) on the efficiency of the magnetic treatment was examined. The Ca(II) ion concentration, pH, conductivity and ORP of the system were monitored throughout the entire duration of the magnetic water treatment. A flow rate of 0.5 L/min, initial [HCO3-]/[Ca+2] concentration of 1.0 and operating temperature of 250C are the optimum condition in the inhibition of calcium carbonate scale formation, which gave the least value in % decrease in terms of ionic Ca(II) concentration. Additional characterization tests and calculations are needed to provide a more comprehensive understanding regarding the effect of the presence of a magnetic field on the mechanism of calcium carbonate precipitation.