Refinery Production Planning And Scheduling Problems And Improved Outer Approximation Algorithms

With the increasing complexity of the market competition of international petrochemical industry, as well as the continued volatility of the crude oil supply market, refining enterprises can get the initiative in the increasingly fierce market competition through scientific and rational optimization of oil refineries in terms of production planning and scheduling. Therefore, people are more and more concerned of the production planning and scheduling problems of refinery. Over the.years, many experts achieved excellent research results.Production planning and scheduling problems of refinery include crude oil processing planning, the scheduling of units arid gasoline blending scheduling. Planning and scheduling problems associate with the many practical problems, for example, the inventory and demand of products and also the operation of the production units. Therefore, the production planning and scheduling problems of refinery to be solved is to make the production plan in a reasonable way to meet the customer demand combined of the actual production problems, enable enterprises to maximize the benefits.Two questions were mainly contained in this thesis:one is the refinery production planning problem; the other is a short-term/scheduling problem of oil blending. They are the keys of the refinery. The aim of the production planning of the refinery is to decide which mode of operation to use in each processing unit at each point in time, in order to satisfy the demand while minimizing the production cost and taking storage capacities into account. The production cost includes costs for changing mode and for holding inventory. Furthermore, the thesis will consider the development and solution of optimization model for short-term scheduling of a set of operations that includes:product receiving from processing units, storage and inventory management in intermediate tanks, blending in order to attend oil specifications and demands, and transport sequencing in oil pipelines. The aim of the optimization model is to minimize the cost. The cost includes raw material cost, pumping cost, inventory cost and transition cost.Two Models were established for above two problems respectively, and solved by CPLEX and OA algorithm, improved OA algorithm. Through the solving of two optimization models, the enterprises can meet market demand and save production costs, increase economic efficiency, improve technology and management level, at the same time, enhance the competitiveness of enterprises, with the guidance of the role and significance of the actual production.In addition, refinery production planning system was developed for refinery production planning problems in this thesis. System mainly consists of log, processing flow diagrams, static information management, production planning management, optimization algorithm.