YAN Xueli, HAN Yuxin, GU Xingsheng. Improved schedule model for batch production by state unit network[J]. CIESC Journal, 2018, (3): 913-922.DOI: 10.11949/j.issn.0438-1157.20171406.
Establishing effective model for scheduling batch process has always been a hot spot of production planning research. Continuous-time model based on unit-specific-event is evolved as a promising tool for optimizing short-term schedule of batch process. A nonlinear programming model for contiguous batch production was developed on the basis of state unit network and specific event time point. To overcome challenges of solving nonlinear model
a replacement technique was used so that non-linear items in the model were linearized. Consequently
the nonlinear mixed integral program model became a linear one. Because of no big M relaxation item
the linear mixed integral model had compact search space and improved solving efficiency. The simulation results of three batch processes illustrated excellent efficiency and stability of the new model. Furthermore
constraints of the new model at different storage states were provided to expand model applicability.