A Hybrid Slot-Based/General Precedence Approach for Planning Crude Oil Supplies

PEDRO C. PAUTASSO; DIEGO C. CAFARO; VANINA G. CAFARO; JAIME CERDÁ

Barcelona

Congreso; 10th World Congress of Chemical Engineering (WCCE 10); 2017

EFCE Spain Group

This work introduces a mixed-integer nonlinearprogramming (MINLP) formulation based on a hybrid approach, combining thepotentials of slot-based and general precedence continuous-timerepresentations. We use general precedence sequencing variables to coordinateincoming/outgoing flows to/from every tank, and simultaneously address thescheduling of a long-distance pipeline supplying crude oil batches from harbourto refinery tanks, following a slot-based scheme. The model is able toprecisely monitor key component concentrations keeping oil properties withinadmissible ranges. One of the most important decisions is how to manage oilshipments so as to improve logistics efficiency. Results show that the use ofslot-based frameworks combined with general precedence variables for sequencingtasks in linking resources yields orders-of-magnitude savings in thecomputational effort to reduce costs and find optimal solutions.