S-graph

The S-graph framework is an approach to solving batch process scheduling problems in chemical plants.

[1][2] S-graph is suited for the problems with a non-intermediate storage (NIS) policy, which often appears in chemical productions, but it is also capable of solving problems with an unlimited intermediate storage (UIS) policy.

[2] The S-graph representation exploits problem-specific knowledge to develop efficient scheduling algorithms.

Different processing times can be set for the same task in different equipment types.

It is possible to have more pieces of equipment of the same type, or define changeover times between two tasks performed on a single piece of equipment.