(72s) Simultaneous Scheduling of Front End Crude Transfer and Refinery Processing

               Simultaneous Scheduling of Front End Crude Transfer and Refinery Processing

Jialin Xu, Shujing Zhang, Jian Zhang, and Qiang Xu

Dan F. Smith Department of Chemical Engineering

Lamar University, Beaumont, TX 77710

Abstract

Scheduling and planning of crude oil is very important to a petroleum refinery due to the potential realization of large cost savings.  It is also the one of most challenging problems for refinery operations. In this paper, a new continuous crude scheduling model has been proposed to simulate and optimize the front-end and refinery crude-oil operations. This scheduling problem involves crude oil unloading from vessels to the crude storage tanks at onshore berths, transfer of crude from these tanks to the charging tanks, charging crude distillation units with crude mixes from the charging tanks and further processing of crude inside the refinery, which includes crude distillation, cracking, coking, reforming, hydrotreating, product blending and component recovery.

The objective of the proposed crude scheduling problem is to maximize the total operational profit; meanwhile, it should meet inventory and production demands, and try to maintain refinery plant’s normal operations under uncertainties. The scheduling model is a large-scale mixed integer nonlinear programming problem(MINLP). An outer-approximation based decomposition method is implemented to obtain the optimum solution of the developed MINLP scheduling model.