An integrated steering approach to improve a phosphate supply chain efficiency

This paper presents and illustrates an original application of the redesign in the real context of a mining supply chain producing phosphate rock. One of the major challenges is to successfully produce merchantable ores (MO) required by the customers, from source ores whose chemical composition and availability depend on the extraction program and method. Redesign of the mining supply chain consists of integrating the heterogeneity of raw materials and the infrastructure to improve the steering mode and to achieve target objectives. In our case, the redesign allows moving from fixed production flows by MO to dynamic ones by adopting a flexible and reactive management mode that fully satisfies customer requirements. This is realized through the determination of the optimal production path followed by each ingredient composing each MO including blends to use (quantities and alternative routing) and periods of resources mobilisation by a developed mixed-integer linear programming model. The main objective concerns minimising a cost function subject to ingredients availability in stocks and their chemical characteristics, customers' expectations, and infrastructure capacity and availability. Numerical results illustrate the flexibility, adaptability, and efficiency ensured by this work.