本研究藉由熱裂解技術產製蓖麻籽裂解油，並利用熱重分析儀探討其裂解與氧化反應隨溫度之變化。結果顯示蓖麻裂解油主要裂解與氧化反應區間發生在100-500℃之間，而最大質量損失率發生在100-320℃之間。其非揮發組分在500℃左右可被引燃，並殘餘約0.18%的殘渣，顯示蓖麻裂解油具有低灰分之特點。而利用熱重分析結果同時也計算了蓖麻熱裂解油引燃溫度、燃盡溫度及綜合燃燒特性指數S。

本研究同時利用懸掛液滴實驗系統，探討不同環境溫度(350℃、450℃及550℃)下蓖麻裂解油滴之受熱行為、微爆現象及燃燒模式。蓖麻籽裂解油為多組分之燃油，因此具有寬廣的沸點範圍，使其受熱過程中行為複雜，並有微爆現象發生，造成液滴表面扭曲變形。其微爆情況依照產生之時機與微爆強度，可區分成三種主要模式：前期的低強度微爆、中期的高強度微爆及後期的中強度微爆。

蓖麻裂解油在環境溫度550℃下發生強微爆後，會釋出較多的揮發油氣並形成可燃油氣，其在高溫環境下被點燃後會形成球對稱之非預混火焰包圍住液滴。液滴燃燒過程中頻繁地發生微爆，但仍能維持接近球體之樣貌，迅速蒸發並維持火焰包住液滴。液滴燃燒後期，揮發性組分皆已揮發掉後，殘留的固態顆粒會接續燃燒，且燃盡後幾乎沒有殘餘物。

In the study, castor oil is produced by thermal pyrolysis and its pyrolysis reaction and oxidation reactions are investigated using thermal gravimetric analysis. The results showed that the main pyrolysis and oxidation reactions occur in the temperature between 100 and 500 °C. The maximum weight loss occurs between 100 and 320 °C. Its non-volatile components may be ignited at about 500 °C and the residue is only about 0.18% of the original weight of the pyrolytic oil. The results of thermal gravimetric analysis are also used to calculate the ignition temperature, burnout temperature and combustion characteristics index (S) of castor pyrolytic oil.

In this study, the suspended droplet experimental system is also used to explore the micro-explosion phenomena and combustion modes of castor pyrolytic oil under different ambient temperatures (350 °C, 450 °C and 550 °C). The pyrolytic oil of castor seeds is a multi-component fuel and therefore has a wide boiling range. It results in a complex process during heating process and micro-explosion occurrs, causing the droplet surface distortion. According to the timing and strength of the micro-explosion, there are three different stages: low intensity micro-explosion in the first stage, high intensity micro-explosion in the second stage and medium intensity micro-explosion in the last stage.

After strong micro-explosion occurred in 550 °C ambient temperature, it will release more volatile vapor and the flammable mixture will form a non-premixed flame wrapping droplets after it is ignited in high temperature environments. During the combustion process of the droplet, the micro-explosion occurs continuously, but the droplet still maintains the appearance close to a sphere. The droplet rapidly evaporates and the flame wraps the droplet. In the latter period of the droplet combustion, volatile components have been completely evaporated, residual solid particle will continue burning, and there is almost no residue after burning.

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