Distribution planning of bulk lubricants at an energy company

We address the distribution planning problem of bulk lubricants at an energy company operating in Turkey. The problem is a multi-product, multi-period, heterogeneous fleet management problem that involves the assignment of customer orders and routing of tank trucks by minimizing the routing costs. To solve this problem we develop a 0-1 mixed-integer linear programming model. Since the problem is intractable for real world data we propose two heuristic approaches and discuss their performances. The first approach is a linear programming relaxation-based algorithm while the second is a threshold accepting heuristic. We propose two variants of this heuristic, the first uses the distance priority whereas the second has a due date priority. The numerical results show that both threshold-accepting heuristics have competitive performance