Integrated tactical production planning with multi transportation modes and multi supply sources: the case of a phosphate supply chain
In the world's largest phosphoric supply chain (SC), the determination of the tactical planning combining (i) the transformation of phosphoric source ores (SO) extracted from mines into different merchantable ores (MO) respecting specific quality charts (QC), partly produced in washing lines using with alternative routings and (ii) its transportation in a network connected to final customers (local customer being phosphoric acid plants and external customers exporting MO by boat) using either a 187 km pipeline or trains, is a considerable challenge. Currently, in decision-making, this problem is simplified by several predeterminations arising from an a priori assignment of orders to a transport mode combined with SC resource sharing (available SOs, production plants); in addition, predefined production recipes are used, involving the routing to use, and constraining the SOs mix to produce a MO. This organisation is becoming less efficient due to customer QC being increasingly restrictive. In addition, the assignment constraints make this organisation less effective than it could be by removing them. This paper proposes a new integrated approach in a global MIP model to support this tactical planning decision, relaxing these used restrictions and an original solution for decision alignment. A case study illustrates this approach.