(703h) Continuous-Time Models for Scheduling of Parallel Batch Digesters for Pulp Production
AIChE Annual Meeting
Thursday, November 17, 2016 - 2:43pm to 3:02pm
In this work, we consider scheduling of both conventional and displacement batch digesters using a resource-task-network (RTN) representation of production recipes, based on unit-specific event based continuous time representation resulting in a MILP problem. The basic framework is adapted from the unit-specific event based models [4-5] dealing with unification of STN/RTN representations and generalization of resource balances. The objective of the scheduling problem is either maximization of production or maximization of total duration of heating and cooking tasks which in turn reduces the overall energy consumption. Illustrative case studies will be presented on both conventional and displacement batch digesters for a digester house comprising of two parallel production lines with four digesters for producing pulp of two different qualities, to demonstrate the proposed modifications and comparison of results with discrete time model .
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