在成核結晶過程中，大多使用批次式生產，其缺點為混合效果不佳，混合過程中的過飽和度分佈不均勻，凝結核形成時間不均及成長滯留時間不一，造成粒徑分佈廣。為了改善此現象，本實驗採用流動的方式來控制成核及結晶過程，探討結晶系統中，過飽和度與溫度對晶體外觀、平均粒徑與分佈之影響，並建立流動式晶體成核與成長技術。本實驗可區分為二大部分，第一部分主要探討混合效率，除使用示波器搭配放大電路測試，也使用染料測量混合長度，探討混合長度隨內外管流速比變化之關係式。第二部分應用於碳酸鈣結晶，探討不同溫度和過飽和度對結晶晶態，粒徑分佈之影響。
結果顯示，從示波器探討混合效率實驗得知內外管流速比愈大，混合效果愈好，而在使用染料探討混合效率實驗中，可了解會有一臨界流速比存在，使得混合長度趨近於零，即代表著混合效率良好。在合成碳酸鈣結晶中，經由XRD得知溫度愈高，calcite晶型所佔比例愈低，vaterite和aragonite晶型所佔比例愈高；過飽和度愈高，粒徑會愈小。在OM和SEM量測中，可得到晶形隨溫度以及過飽和度之變化。在加入界面活性劑之後，可有效的使晶體粒徑變小。

Batch production is generally used in the crystallization process. However, batch production has several disadvantages: it has poor mixing efficiency ,thereby the supersaturation is not distributed evenly which leads to a unevenly nucleation rate. But the time for each nucleus formation and the time for crystal to grow are not uniform. This results in broaden size distribution. In order to improve the phenomenon, we employed a flow process for nucleation and growth. We design and setup the equipments to develop a flow type crystalline nucleation and growth process.
The effects of supersaturation and temperature on the appearance of crystal, mean particle diameter, and particle size distribution were discussed. This study is divided into two parts: on the first part, the mixing efficiency was examined using an oscilloscope and an operation amplifier. On the other hand, a black dye was used for a visual measurement of the mixing length to obtain a correlation of the lengths with velocity ratio. On the second part, the experiments for the generation and growth CaCO3 crystal were performed under different temperatures and supersaturations.
From the measurement using an oscilloscope to detect mixing efficiency, we find that the higher velocity ratio the better mixing is. In the dye visualization experiment, a critical velocity ratio was found at which the mixing length approaches to zero, i.e., instantly well mixing. In the formation of CaCO3 ,the XRD results showed that the higher temperature, the lower calcite composition and the higher vaterite and aragonite composition were obtained; the higher supersaturation, the smaller particle size and vice versa. The images of OM and SEM ,show an obvious variation of morphology with temperature and supersaturation; and the addition of surfactant , leads to a formation of smaller particles.

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