Spectroscopic monitoring of batch reactions for on-line fault detection and diagnosis

This paper presents the general methodology to use spectroscopic measuremen ts directly for on-line process monitoring and detection and diagnosis of d isturbances. An application of the on-line monitoring of a chemical batch r eaction using UV-visible spectroscopy is discussed in detail. Successful hi storical batches are used to build a statistical model of the batch reactio n. The model uses external information such as the pure spectra of the comp ounds and their concentration profiles to improve the interpretability. Con trol charts are developed for on-line monitoring of nea batches. It is show n that this model is capable of detecting erroneous batches. In combination with contribution plots,the actual cause of the disturbances can be diagno sed.