A novel monolithic MILP framework for lot-sizing and scheduling of multiproduct treelike pipeline networks

Published in Industrial & Engineering Chemistry Research, 2015


Detailed scheduling of long-distance multiproduct pipelines has received growing attention in the past few years. It helps the planner to reduce the number of pump and segment switches between active and idle conditions to obtain savings on pump operating and maintenance costs. Most contributions on the detailed scheduling of multiproduct pipelines concern networks with a single straight line. Large-scale pipeline networks, however, usually have a treelike configuration, featuring a mainline and several secondary lines, transporting smaller volumes of refined petroleum products over shorter distances. This work addresses the scheduling of a multiproduct treelike pipeline through a continuous-time mixed integer linear programming (MILP) model that allows the execution of simultaneous deliveries from a unique refinery to multiple downstream terminals so as to get a substantial increase in transportation capacity. Contrary to previous contributions on treelike pipeline systems, the new model solves batch sizing and sequencing problems in a single step, generating a detailed delivery schedule. It also handles flow rate limitations in downstream pipeline segments originated from a lower diameter. Three case studies including one real life problem are used to illustrate the efficacy of the proposed model.