基于机理模型的2-KGA混菌发酵过程关键状态变量预报

Key variables prediction based on mechanism models of 2-KGA mixed culture fermentation

维生素C生产的前体2-KGA是巨大芽孢杆菌和普通生酮古龙酸菌混合发酵的产物。利用先前建立的2-KGA混菌发酵动力学模型对背景厂80个批次的实测数据进行分析,结果表明该模型能够很好地符合工业生产的实际情况。在模型参数灵敏度分析的基础上固定了部分模型参数,并选取具有代表性的3个罐批(劣等、普通、优势),利用移动数据窗口技术和滚动参数辨识方法成功地进行了2-KGA浓度和底物浓度的超前4h和8h拟在线预报,预报误差均在5%以内。同时还比较了固定长度时间窗口和变长度时间窗口的预报结果,并根据现场实际数据特点分析了二者的优劣。

2-Keto-L-gulonic acid（2-KGA）,the precursor for vitamin C synthesis,is produced by the mixed culture of Ketogulonicigenium vulgare and Bacillus megaterium.In this paper,the previously established kinetic model for 2-KGA mixed culture was firstly tested with the data of 80 industrial batches.Based on sensitivity analysis,it was found that some insensitive parameters might be assigned fixed values to minimize computing time.Then,the model was used to predict the most important state variables,i.e.,substrate and product concentrations.Moving data window technique and rolling parameter identification approach were used in the prediction process.4 h and 8 h ahead prediction errors for 2-KGA concentration were less than 5%.