Resumen de Collection of diferent types of milk with multi‑tank tankers under uncertainty: a real case study

Olcay Polat, Duygu Topaloğlu

• The milk collection problem can be basically defned as the daily collection of raw milk from diferent points (farms/milk collection centers) and delivering it to a dairy facility. To enhance fnal dairy quality, it is important to use the appropriate quality of raw milk for each dairy product. However, collecting diferent types of milk comes with additional logistics costs which signifcantly increase in an uncertain environment. In this study, we, therefore, propose a novel mathematical model for the collection of diferent types of milk from producers by multi-tank tankers with split deliveries, uncertain demand, service time and vehicle speed conditions. A real-life case study from a dairy company is solved under diferent risk assessment scenarios. Indeed, several brand-new benchmark instances for the core problem are presented and solved by utilizing an efcient heuristics approach called enhanced iterative local search. All the case study results show that considering the uncertainty is very critical for designing efcient collection networks. The fndings of the study indicate that logistics decision makers should design their collection networks with low, but non-zero, risk levels.