| 摘要: | 本論文應用間歇式加壓流體化石灰石床系統進行新的處理程序，以探討含鐵酸水之研究。此處理程序已經證明了添加入CO2壓力及管柱流體所形成流體化現象，可減少包覆的產生，使得碳酸鈣持續溶解，提高中和酸水的能力；除外，亦具有石灰石成本較低廉，處理速度快且處理水量大等優點。
本論文主要研究，藉由改變不同的系統條件-原水酸度的變化、原水鐵濃度的變化、加入CO2壓力的變化與碳酸鈣添加量的變化-來探討碳酸鈣的溶解狀況、鐵的去除效率和碳酸鈣表面的分析。本文中，碳酸鈣溶解狀況採用五種計算方式：(1) LD(AA) (2) LD（ Alk）(3) LD(pH-Alk) (4) LD(pH-Alk)和(5) LD(電荷平衡)；碳酸鈣表面的分析則採用SEM、EDS和XRD之方法。
研究結果發現：
(1)當CO2壓力的增加、原水酸度的增加或原水中鐵濃度的增加，分別可使水中碳酸鈣的溶解量(LD)增加；利用五種方式計算出LD值為：pH-總鹼度 > AA ≥ 電荷平衡 ≥總鹼度> pH-Alk，本研究建議在計算LD值時可採用LD (AA)、LD (電荷平衡)和LD (總鹼度)三種方式計算，其值較為接近實際值。
(2)此系統在鐵的去除效果可達到去除率皆大於98%以上
(3)經SEM、EDS和XRD方法分析得知，當CO2壓力增加時，原水酸度的增加，不易造成氫氧化鐵的沉澱於顆粒的表面。
Fluidized Pulsed Limestone Bed System (FPLB) was applied in this research on iron-contained acid water. This new process was proved that the fluidized phenomenon caused by circulating flow could decrease the production of armor precipitation in order to sustain the dissolution of limestone, and increase the extent of acid neutralization capacity. In addition, lower cost of limestone and efficienctly remediating mass ammont of acid water are the most benefits.
This research focus as the on dissolution status of limestone, iron removal efficiency and the effects of limestone surface precipitation, based on different controls of the variation in acidity, iron concentration, applied CO2 pressure and limestone addition. As for analysis, the limestone dissolution (LD) was calculated by five methods: LD(AA), LD（ Alk）, LD(pH-Alk), LD(pH-Alk) and LD(charge balance); SEM, EDS, and XRD were applied to analyze the surface precipitation of limestone as well.
The results of this research reveal three main points as follows:
First, the amount of limestone dissolution is increased with the increasing of applied CO2 pressure、influent acidity or iron concentration. Besides, the LD value could be performed as：LD (pH- Alk) > LD (AA ) ≥ LD (charge balance) ≥ LD ( Alk )> LD (pH-Alk). The suitable methods of calculating LD valve in our analyze are LD (AA)、LD (charge balance) and LD ( Alk), because of its similarty.
Second, iron removal efficiecy could be up to 98 percent by applying FPLB to this experiment.
Third, analyzed by SEM, EDS and XRD, ferric hydroxides would be hardly precipitated on the surface of limestone while increasing applied CO2 pressure or influent acidity. |
