A Hierarchical Optimization Approach to Optimal Production Scheduling in an Industrial Continuous Olefin Polymerization Reactor

Chatzidoukas, Christos; Pistikopoulos, Stratos; Kiparissides, Costas

doi:10.1002/mren.200800030

Cited by 25 publications

(20 citation statements)

References 20 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…For the quality variable of cumulative melt index MI c (t), it can be described as (1) in which MI i (t) is the instantaneous melt index and parameter τ MI is decided by the inflow and outflow rates. For the quality variable of cumulative density ρ c (t), it can be described as the similar form of…”

Section: Industrial and Engineering Chemistry Researchmentioning

confidence: 99%

See 1 more Smart Citation

Three-Stage Decomposition Modeling for Quality of Gas-Phase Polyethylene Process Based on Adaptive Hinging Hyperplanes and Impulse Response Template

Wei

Jiang

Yang

et al. 2013

Ind. Eng. Chem. Res.

View full text Add to dashboard Cite

It is difficult to establish a dynamic model of quality variables in polymerization, because of the high complexity of the nonlinear process behavior and time-consuming laboratory quality measurements. A decomposition scheme is presented in this paper to model the dynamic nonlinear behaviors of the gas-phase polyethylene process, by decomposing the overall process based on its structure into three relatively simpler problems. However, difficulties still come from nonlinearity and nonuniform sampling. Especially, the samples of the product quality in the transitional process are too deficient for traditional data-driven methods. In order to further overcome the difficulties incurred by nonlinearity, the adaptive hinging hyperplanes (AHH) model is adopted. Meanwhile, an impulse response template (IRT) is introduced to model the accumulation process dynamics to deal with the scarcity of sampled data. The proposed model is validated to be effective in comparison with black-box models on the melt index data of 10 transitional processes.

show abstract

Section: Industrial and Engineering Chemistry Researchmentioning

confidence: 99%

“…1 Therefore, accurate dynamic models of the crucial quality variables are important for process control. Because most processes involve a mixing stage, the corresponding indices, such as melt index, density, and molecular weight, perform cumulative characteristics.…”

Section: Introductionmentioning

confidence: 99%

Three-Stage Decomposition Modeling for Quality of Gas-Phase Polyethylene Process Based on Adaptive Hinging Hyperplanes and Impulse Response Template

Wei

Jiang

Yang

et al. 2013

Ind. Eng. Chem. Res.

View full text Add to dashboard Cite

show abstract

“…Chatzidoukas et al demonstrated the economic benefit of implementing scheduling in a MIDO problem for polymerization, solving product grade transitions along with the scheduling problem [22]. Economic benefit has also been shown for simultaneous selection of linear controllers for grade transitions and scheduling, ensuring that the process dynamics from the controller selection are accounted for in the scheduling problem [23]. Terrazas-Moreno et al also demonstrate the benefits of process dynamics in cyclic scheduling for continuous chemical processes [45].…”

Section: Previous Workmentioning

confidence: 99%

Economic Benefit from Progressive Integration of Scheduling and Control for Continuous Chemical Processes

et al. 2017

View full text Add to dashboard Cite

Performance of integrated production scheduling and advanced process control with disturbances is summarized and reviewed with four progressive stages of scheduling and control integration and responsiveness to disturbances: open-loop segregated scheduling and control, closed-loop segregated scheduling and control, open-loop scheduling with consideration of process dynamics, and closed-loop integrated scheduling and control responsive to process disturbances and market fluctuations. Progressive economic benefit from dynamic rescheduling and integrating scheduling and control is shown on a continuously stirred tank reactor (CSTR) benchmark application in closed-loop simulations over 24 h. A fixed horizon integrated scheduling and control formulation for multi-product, continuous chemical processes is utilized, in which nonlinear model predictive control (NMPC) and continuous-time scheduling are combined.

show abstract

“…Chatzidoukas et al study solving the simultaneous dynamic optimization optimal grade transitions and scheduling problem for fluidized-bed reactors (FBR) via a MIDO approach with orthogonal collocation on finite elements [35]. They also study simultaneous selection of closed-loop controllers and selection of controller parameters with the scheduling problem for polymerization processes [36,37]. Terrazas-Moreno and Flores-Tlacuahuac also investigate simultaneous cyclic scheduling and control of continuous chemical processes, and study a langrangean heuristic method for reduction of computational burden [15,18].…”

Section: Literature Reviewmentioning

confidence: 99%

Combined Noncyclic Scheduling and Advanced Control for Continuous Chemical Processes

et al. 2017

View full text Add to dashboard Cite

Abstract:A novel formulation for combined scheduling and control of multi-product, continuous chemical processes is introduced in which nonlinear model predictive control (NMPC) and noncyclic continuous-time scheduling are efficiently combined. A decomposition into nonlinear programming (NLP) dynamic optimization problems and mixed-integer linear programming (MILP) problems, without iterative alternation, allows for computationally light solution. An iterative method is introduced to determine the number of production slots for a noncyclic schedule during a prediction horizon. A filter method is introduced to reduce the number of MILP problems required. The formulation's closed-loop performance with both process disturbances and updated market conditions is demonstrated through multiple scenarios on a benchmark continuously stirred tank reactor (CSTR) application with fluctuations in market demand and price for multiple products. Economic performance surpasses cyclic scheduling in all scenarios presented. Computational performance is sufficiently light to enable online operation in a dual-loop feedback structure.

show abstract

A Hierarchical Optimization Approach to Optimal Production Scheduling in an Industrial Continuous Olefin Polymerization Reactor

Cited by 25 publications

References 20 publications

Three-Stage Decomposition Modeling for Quality of Gas-Phase Polyethylene Process Based on Adaptive Hinging Hyperplanes and Impulse Response Template

Three-Stage Decomposition Modeling for Quality of Gas-Phase Polyethylene Process Based on Adaptive Hinging Hyperplanes and Impulse Response Template

Economic Benefit from Progressive Integration of Scheduling and Control for Continuous Chemical Processes

Combined Noncyclic Scheduling and Advanced Control for Continuous Chemical Processes

Contact Info

Product

Resources

About