青霉素发酵过程的模型仿真与补料优化

补料分批式青霉素发酵的机理模型已得到深入研究,但是模型往往难以用于补料的优化和批次内的控制。为了对模型进行优化控制,针对Birol等提出的青霉素发酵非结构动力学模型,合理调整了温度和pH变化的影响,得到了青霉素发酵过程的简化机理模型。反应基质的补料是青霉素优化控制的关键,选择对补料速率进行优化来提高青霉素的产量。由于机理模型具有非线性和约束条件,采用序贯二次规划算法来进行求解,其中将补料轨线进行分段处理提高了优化效率。优化计算结果表明改进的补料过程可以提高青霉素的浓度和产量。

Model simulation of fed-batch penicillin fermentation and optimization of substrate feedrate

The mechanical model of fed-batch penicillin fermentation has been well studied for the last decades,but most of them can hardly be implemented to control fermentation process.Due to this problem,this paper uses Birol’s unstructured model,adjusts temperature and pH dynamics of the fermentation and deduces a simplified penicillin unstructured model.To increase production of penicillin,substrate feedrate which is critical in fermentation process is optimized.Because of the nonlinearity and constraints of the mechanical model,sequential quadratic programming(SQP)algorithm is used to the whole process,in which the feedrate trajectory is divided equally into several intervals to enhance optimization efficiency.Optimization results show that the penicillin concentration and yield are increased compared to the normal input.