A Step-wise sequential phase partition algorithm with limited batches for statistical modeling and online monitoring of multiphase batch processes

Abstract

For batch processes, sufficient batches are in general required for statistical modeling and process monitoring. However, sometimes, it is difficult and may be impractical to conduct multiple cycles and wait until enough batches are available. Thus, how to derive reliable process information based on limited batches has been an important question. Starting from limited modeling batches, this article proposes a phase partition and process monitoring strategy for multiphase batch processes. First, a step-wise sequential phase partition algorithm is developed with limited batches where a generalized time-slice is constructed by combining several consecutive time-slices within a short time region to analyze changes of process characteristics. Multiple phases are thus identified in sequence along time direction which are described by different phase models. The feasibility and performance of the proposed method for online process monitoring are illustrated with experimental data from a typical multiphase batch process.