RWTH Aachen, AVT-Biochemical Engineering, Worringer Weg 1, 52056 Aachen, Germany.
Biotechnol Bioeng. 2013 Jan;110(1):180-90. doi: 10.1002/bit.24601. Epub 2012 Jul 25.
Calorimetry is a robust method for online monitoring and controlling bioprocesses in stirred tank reactors. Up to now, reactor calorimeters have not been optimally constructed for pilot scale applications. Thus, the objective of this paper is to compare two different ways for designing reactor calorimeters and validate them. The "heat capacity" method based on the mass flow of the cooling liquid in the jacket was compared with the "heat transfer" method based on the heat transfer coefficient continuously measured in the cultivation of Escherichia coli VH33 in a 50 L stirred tank reactor. It was found that the values of the "heat transfer" method agreed very well with the calculated values from the oxygen consumption. By contrast, the curve of the "heat capacity" method deviated from that of the oxygen consumption calculated with the oxycaloric equivalent. In conclusion, the "heat transfer" method has been proven to have a higher degree of validity than the "heat capacity" method. Thus, it is a better and more robust means to measure heat generation of fermentations in stirred tank bioreactors on a pilot scale.
量热法是一种用于在线监测和控制搅拌釜式反应器中生物过程的强大方法。到目前为止，对于中试规模的应用，反应器量热器的结构还没有得到最佳优化。因此，本文的目的是比较两种不同的设计反应器量热器的方法并对其进行验证。基于夹套中冷却液体质量流量的“热容”方法与基于连续测量的大肠杆菌 VH33 在 50L 搅拌釜式反应器中培养过程中的传热系数的“传热”方法进行了比较。结果发现，“传热”方法的值与耗氧量计算出的值非常吻合。相比之下，“热容”方法的曲线与用比热当量计算出的耗氧量曲线不符。总之，“传热”方法已被证明比“热容”方法具有更高的有效性。因此，它是一种更好、更可靠的方法，可在中试规模下测量搅拌罐生物反应器中发酵的产热量。
