Analysis and Optimization of Mycelial Fermentors

这项拟议的研究将表征菌丝发酵中的气液传质，并利用菌丝发酵模型优化反应器性能。用一种新的测定传质系数的化学技术来表征气液传质过程。开发了一种利用臭氧和蓝色染料之间的瞬时反应的非稳态化学技术，由于离子强度低，数据收集和分析容易，因此非常适合于模拟菌丝发酵。生物相将由纤维素纤维模拟，它在悬浮液中的行为类似于菌丝体的生长。该模型系统将被用来描述各种搅拌反应器中的气液传质与搅拌速度、放气率和固体浓度之间的关系。用水翼式搅拌器取代涡轮搅拌器具有重要的工业意义，主要是因为节省了能源，菌丝液的剪切暴露更低。由黑曲霉将葡萄糖转化为葡萄糖酸的反应将在最有希望的反应器中进行，以确定气液传质的改善是否转化为菌丝体反应器性能的改善。

The proposed research will characterize gas-liquid mass transfer in mycelial fermentations and optimize reactor performance utilizing a model mycelial fermentation. A new chemical technique for the measurement of mass transfer coefficient will be utilized to characterize the gas-liquid mass transfer. An unsteady-state chemical technique utilizing an instantaneous reaction between ozone and indigo dye has been developed and is well- suited for modelling mycelial fermentations because of low ionic strengths and ease of data collection and analysis. The biological phase will be modeled with cellulose fibers, which in suspension behave similarly to mycelular growths. This model system will be used to characterize the gas- liquid mass transfer as a function of stirrer speed, gassing rate and solids concentration in a variety of agitated reactors. The replacement of turbine agitators with hydrofoil impellers has significant industrial interest, primarily due to energy savings and lower shear exposure for the mycelial broth. The reaction of glucose to gluconic acid by Aspergillus niger will be carried out in the most promising reactor configurations to determine if the improvements in gas-liquid mass transfer translate into improvements in the mycelular reactor performance.