State Task Network for the scheduling of multiproduct batch plants.
STN is a scheduling model that can be applied to a large number of batch processes that are
specified by recipies, it is concerned with short-term scheduling in which demands of products
are specified at various points in time in the form of deadlines. The MILP model that is used
was developed by Kondili et al. (1993), and has the folowing three major
capabilities:
1. Assignments of equipment to processing tasks need not to be fixed.
2. Variable size batches can be handled with the possibility of mixing and splitting.
3. Different intermediate storage and transfer policies can be accommodated as well
as limitations of resources.
The major assumption that will be made is that the time domain can be discretized in intervals
of equal size.
This network has two types of nodes: (a) state nodes that correspond to feeds,
intermediates, and final products; and (b) task nodes that represent processing steps.
STN was developed by Gabriela Garcia-Ayala under the supervision of
Ignacio E.Grossmann.
For discrete time model:
Kondili, E., Pantelides, C. C., & Sargent, W. H. (1993). A general algorithm
for short-term scheduling of batch operations-I. MILP formulation.
Computers and Chemical Engineering, 2, 211 - 227.
Shah, N., Pantelides, C. C., & Sargent, W. H. (1993). A general algorithm
for short-term scheduling of batch operations-II. Computational issues.
Computers and Chemical Engineering, 2, 229 - 244.
For continuous time model:
Maravelias, C.T.; Grossmann, I.E. New Continuous-Time State Task Network Formulation for the Scheduling of Multipurpose Batch Plants. Industrial and Engineering Chemistry Research, 2003, 42 (13), 3056-3074, 2003.