Dispatching for batch chemical processes using Monte-Carlo simulations - A practical approach to scheduling in operations

In this chapter, we introduce a practical approach to the solution of dispatching and scheduling problems on the shop floor. Due to the stochastic nature of scheduling problems in the process industry, we suggest an online scheduling strategy, which only computes a small sequence of next jobs, or even just one next job, at a time. We combine this approach with a Monte-Carlo simulation of the plant, to predict ready times of crucial production equipment. These ready times are fed into the scheduling algorithm as inputs. Thus, the algorithm always has the most up-to-date knowledge about all necessary equipment, as well as predictions about relevant future information. As part of a case study, we show how this general solution approach can be implemented in practice, including the connection to the plant’s IT infrastructure, as well as a tailor-made graphical user interface to best visualize our decision support for an operator.