Integrated tactical continuous production planning of two blending systems sharing supply sources: the case of a phosphate supply chain

The tightening of product quality requirements by customers on merchantable phosphate ores (MOs) prevents the world's largest phosphate production site from continuing to plan its production with the current rules. This paper deals with a problem of tactical planning of production activities and considers the case of a phosphate SC covering hundreds of km2, with several mines, several washing plants, and a drying plant, with transport of MOs by rail or pipeline. MOs are obtained by blending ores (SOs) of varying compositions and volumes. Currently, the plants are managed quite independently, SOs are pre-assigned to the MOs, and the MO production routings in the washing plants are predetermined. We propose a model that ensures flexibility in the production of MOs through the choice of dynamic blends and routings. Our approach goes beyond any pre-allocation of resources and aims at synchronising the flows of the washing plants. This specific problem of blending production and planning has not been addressed in the scientific literature. Still, it is widely encountered in many mining industries and offers perspectives for the application of the approach proposed in this paper. Numerous tests show that this model makes it possible to respect the quality constraints related to the composition of several chemical components, with a generalised use of the most economical routings while ensuring horizontal and vertical alignment of decisions.

客户对可销售磷矿石（MOs）产品质量要求的日益严格，导致全球最大的磷矿石生产基地无法继续按照现行规则制定其生产计划。本文探讨了一种生产活动的战术规划问题，并考虑了一个覆盖数百平方公里面积的磷矿石开采区案例，该区域拥有多个矿山、多个洗涤厂和一座干燥厂，以及通过铁路或管道运输的MOs。MOs通过混合不同成分和体积的矿石（SOs）获得。目前，各工厂管理相对独立，SOs预先分配给MOs，洗涤厂中的MOs生产流程预先设定。我们提出了一种模型，通过动态混合和路线选择确保MOs生产的灵活性。我们的方法超越了任何资源预分配，旨在同步洗涤厂的物料流动。这种混合生产与规划的具体问题在科学文献中尚未得到解决，然而，它在众多采矿行业中普遍存在，并为本文提出的方法的应用提供了前景。众多测试表明，该模型能够在保证经济路线广泛使用的同时，确保决策的横向和纵向一致性，从而满足与多种化学成分组成相关的质量约束。