Dan F. Smith Department of Chemical and Biomolecular Engineering

College of Engineering

Comprehensive Optimization for Supply Chain Management

Short Description

This research project consists of three broad studies that have been performed at Dr. Xu’s research group for over 15 years, which  include: (i) port-related supply chain management (PSCM) related to refineries/chemical/ petrochemical industries; (ii) optimal scheduling for decoking operation of ethylene cracking furnace system; and (iii) hoist scheduling for multi-recipe and multi-stage material handling processes. 

Project PI

Dr. Qiang Xu, Professor, Dan F. Smith Department of Chemical Engineering

Full Description

The PSCM study covers crude/raw material purchasing, vessel shipping, unloading and storage in ports, inland transportation, blending and discharging, plant manufacturing, and product marketing. We have developed a series of robust or reactive PSCM methodology for short-term and middle-term planning and scheduling crude/raw material logistic ranging from purchasing, transportation, manufacturing, to final marketing. The developments focus on synergies of port and industrial supply-chain management to minimize the PSCM cost and operating risk. They can handle multiple unit maintenance issues under various uncertainties such as shipping delay, product demand change, and storage/charging tank unavailability as well.

The scheduling for ethylene cracking furnace system employs multiple cracking furnaces in parallel to convert various hydrocarbon feedstocks to multiple smaller-molecule hydrocarbon products. The operation is also a typical semi-continuous dynamic process, where a cracking furnace has to be periodically shut down for decoking. Given the data of multiple feed characteristics, different furnace performances, various manufacturing costs, and specified operational constraints, an optimal decoking policy for the entire cracking system can be determined to achieve the best economic performance of an ethylene cracking furnace system.

We developed a series of novel scheduling models to generate optimal decoking strategy for the entire furnace system. They can cyclic or dynamic optimize multiple-feed assignments, running length of each batch operation, and decoking sequence for every furnace in the system based on the new feed deliveries, the leftover feeds, and current furnace operating conditions. It also simultaneously addresses major scheduling issues for real cracking furnace operations, such as non-simultaneous decoking, secondary ethane cracking, cold maintenance, seamless rescheduling, or environmental conscious decoking. The developed MINLP (mixed-integer nonlinear programming) model is applicable to any cracking furnace system and can be easily extended to any real ethylene plants.

Hoist scheduling for multi-recipe and multi-stage material handling (M3H) processes are broadly used for manufacturing various products/jobs. When multiple types of jobs with different recipes are simultaneously and continuously handled in a production line, the hoist movement scheduling should be thoroughly investigated to ensure the operational feasibility of every job inline, and in the meantime to maximize the productivity if possible.

In this study, we have developed a series of hoist scheduling strategies to help the manufacturing of M3H processes, including cyclic scheduling, environmental benign scheduling, real-time dynamic scheduling, process design and retrofit oriented scheduling. This study could help improve the production efficiency in various industrial processes, such as electroplating and surface finishing, chemical, food, automotive, and electronics industries.

Funding

Different project aspects were funded by Center for Midstream Management and Science (CMMS), Center for Advances in Port Management (CAPM), Texas Hazardous Waste Research Center (THWRC), Lamar University Enhancement Research Grant.   

Selected Publications

  • Yu, L., Chen, M., Xu, Q.*, “Simultaneous Scheduling of Multi-product Pipeline Distribution and Depot Inventory Management for Petroleum Refineries”, Chemical Engineering Science, 220, 115618-115632, 2020.
  • Qu, H. L., Wang, S. J., Xu, Q.*, “Integrated Proactive and Reactive Scheduling for Refinery Front-end Crude Movement with Consideration of Unit Maintenance”, Industrial & Engineering Chemistry Research, 58, 12192-12206, 2019.
  • Chen, M., Xu, Q.*, “Upset-conscious Scheduling for Continuous Parallel-process and Performance Decaying Unit System”, Chemical Engineering Science, 195, 828-840, 2019. (2019 Best Paper Award of AIChE Process Development Division)
  • Chen, M., Xu, Q.*, “Optimal Scheduling for Olefin Plant Furnace System with Consideration of Inherent Process Upset Reduction”, Computers & Chemical Engineering, 126, 157-167, 2019.
  • Qu, H. L., Xu, J. L., Wang, S. J., Xu, Q.*, “Dynamic Routing Optimization for Chemical Hazardous Material Transportation under Uncertainties”, Industrial & Engineering Chemistry Research, 57(31), 10500-10517, 2018.
  • Xu, J. L., Zhang, J., Xu, Q.*, “Plant-wide Scheduling for Profitable Emission Reduction in Petroleum Refineries”, Industrial & Engineering Chemistry Research, 57 (29), 9471–9488, 2018.
  • Qu, H. L., Xu, J. L., Wang, S. J., Xu, Q.*, “A Novel MINLP Model of Front-end Crude Scheduling for Refinery with Consideration of Inherent Upset Minimization”, Computers & Chemical Engineering, 117, 42-46, 2018.
  • Qu, H. L., Xu, J. L., Wang, S. J., Xu, Q.*, “Optimal Front-end Crude Scheduling for Refineries under Consideration of Inherent Upset Reduction”, Computer Aided Chemical Engineering, 44, 1315-1320, 2018.
  • Qu, H. L., Wang, S. J.*, Xu, Q.*, “Simultaneous 2D Hoist Scheduling and Production Line Design and for Multi-recipe and Multi-stage Material Handling Processes”, Chemical Engineering Science, 167, 251-264, 2017 (2017 Best Paper Award of AIChE Process Development Division).
  • Xu, J. L., Qu, Honglin, Wang, S. J., Xu, Q.*, “A New Proactive Scheduling Methodology for Front-end Crude Oil and Refinery Operations under Uncertainty of Shipping Delay”, Industrial & Engineering Chemistry Research, 56(28), 8041-8053, 2017.
  • Xu, J. L., Zhang, S. J., Zhang J. Wang, S. J., Xu, Q.*, “Simultaneous Scheduling of Front End Crude Transfer and Refinery Processing”, Computers & Chemical Engineering, 96, 212-236, 2017.
  • Qu, H. L., Wang, S. J.*, Xu, Q.*, “A New Method of Cyclic Hoist Scheduling for Multi-recipe and Multi-stage Material Handling Processes”, Computers & Chemical Engineering, 90, 171-187, 2016.
  • Zhang, S. J., Xu, Q.*, “A New Reactive Scheduling Approach for Short-term Crude Oil Operations under Tank Malfunction”, Industrial & Engineering Chemistry Research, 54 (49), 12438-12454, 2015.
  • Zhang, S. J., Xu, Q.*, “Refinery Continuous-time Crude Scheduling with Consideration of Long-distance Pipeline Transportation”, Computers & Chemical Engineering, 75, 74-94, 2015.
  • Zhang, S. J., Xu, Q.*, “Reactive Scheduling of Short-Term Crude Oil Operations under Uncertainties”, Industrial & Engineering Chemistry Research, 53 (31), 12502–12518, 2014.
  • Zhao, C. Y., Fu, J., Xu, Q.*, “Real-time Dynamic Hoist Scheduling for Multi-stage Material Handling under Uncertainties”, AIChE J., 59(2), 465-482, 2013.
  • Zhao, C. Y., Fu, J., Xu, Q.*, “Production-Ratio Oriented Optimization for Multi-recipe Material Handling via Simultaneous Hoist Scheduling and Production Line Arrangement”, Computers & Chemical Engineering, 50(5), 28-38, 2013.
  • Fu, J., Zhao, C. Y., Xu, Q.*, T.C. Ho “Debottleneck of Multi-stage Material-Handling Processes via Simultaneous Hoist Scheduling and Production Line Retrofit”, Industrial & Engineering Chemistry Research, 52(1), 123-133, 2013.
  • Zhang, J., Wen, Y. Q., Xu, Q.*, “Simultaneous Optimization of Crude Oil Blending and Purchase Planning with Delivery Uncertainty Consideration”, Industrial & Engineering Chemistry Research, 51 (25), 8453-8464, 2012.
  • Liu, C. W., Zhao. C. Y., Xu, Q.*, “Integration of Electroplating Process Design and Operation for Simultaneous Productivity Maximization, Energy Saving, and Freshwater Minimization”, Chemical Engineering Science, 68(1), 2012.
  • Liu, C. W., Fu, J., Xu, Q.*, “Simultaneous Mixed-Integer Dynamic Optimization for Environmentally Benign Electroplating”, Computers & Chemical Engineering, 35(11), 2411-2425, 2011.
  • Zhao, C. Y., Liu, C. W., Xu, Q.*, “Dynamic Scheduling for Ethylene Cracking Furnace System”, Industrial & Engineering Chemistry Research, 50(21), 12026 -12040, 2011.
  • Zhao, C. Y., Liu, C. W., Xu, Q.*, “Cyclic Scheduling for Ethylene Cracking Furnace System with Consideration of Secondary Ethane Cracking”, Industrial & Engineering Chemistry Research, 49(12), 5765-5774, 2010. (2011 Best Paper Award of AIChE Process Development Division)
  • Liu, C.W., Zhang, J., Xu, Q.*, Li, K. Y., “Cyclic Scheduling for Best Profitability of Industrial Cracking Furnace System”, Computers & Chemical Engineering, 34(4), 544-554, 2010.