Abstract
本文係針對好氣性生化反應器之設計改良、及其性能上之分析探討，乃至於最後將其實際應用於蘇力菌之醱酵程序上。本文的重點則在對於複雜的醱酵系統做適當的電腦輔助適應控制，而使欲得之蘇力菌素的產率提升，並期能促使生化反應器之設計初衷，可實現在真實之生化程序上。 本文中對所提出之網狀內管之直徑大小，做質傳及混合特性之探討。由空氣－水的實驗証明，在所採用之管徑範圍內，幾乎所有網管之此二性能，在超過一定之氣體流量下，皆可優於氣泡塔。其中最小管徑(6.5公分之直徑)之網管，在高於1.33VVM之通氣量下，更有極佳之質傳提升的效果；並且在逐漸上升之通氣量下，對液相混合性能的增進，亦有凌駕其他網管之趨勢。 在實際的蘇力菌素(生物殺蟲劑)批式醱酵的產程研究上，本文採用具6.5公分導流管徑之網狀內管氣舉式反應器。其中並與氣泡塔及一般常用之攪拌式反應器做比較。由結果顯示，在氣泡塔之低質傳、及攪拌式反應器之高剪力下所得到之產量，皆遜於新反應器之產量。 由於新反應器在蘇力菌素生產上之優越性，故進一步地被採用在饋料批式之生產上。同時進行多種饋料控制策略之應用，並改良了饋料基質之組成。在高層次之電腦輔助適應控制與卓越性能之新反應器的結合下，提供完善之醱酵操作環境，使得蘇力菌素之產量高達13.7 3g/L，為目前文獻中最高產值之十倍以上。Design and performance analysis of an aerated bioreactor havebeen investigated in this dissertation. The reactor was appliedto an aerobic fermentation process for cultivation of Bacillusthuringiensis. The aim of this dissertation was focused onadaptive computer control of the fermentation system to improvethe productivity of thuringiensin. The purpose of thedissertation was also on reactor design for biochemicalprocesses. The airlift reactor with the net draft tube of 6.5cm in diameter was chosen for fermentation application inthuringiensin production. Cultivations were carried out inagitated reactor, bubble column, and the airlift reactor forcomparison. The results exhibited that productions ofthuringiensin in a bubble column and an agitated reactor werelower than that in the new reactor, since the new reactor hadhigher mass transfer rate and lower shear stress in comparisonwith both bubble column and agitated reactor. The productivityof thuringiensin in the new reactor increased 65% in comparisonwith the highest production in the literature. Because of theoutstanding ability for production of thuringiensin, the newreactor was utilized for fed- batch culture. Different feedingcontrol strategies were applied and the composition of feedingsubstrate was modified. By combining adaptive control and thewell performance of the new reactor, a suitable environment forfermentation was provided. Under such operating conditions,production of thuringiensin could reach 13.73 g/L which wasmore than tenfold in comparison with the highest production inthe literature.