Article
Engineering, Chemical
Yingjie Ma, Zekun Yang, Aline El-Khoruy, Nan Zhang, Jie Li, Bingjian Zhang, Li Sun
Summary: This research proposes a computationally efficient optimization framework for simultaneous synthesis and design of reaction-separation-recycle processes. The reactor and separator networks are modeled using generalized disjunctive programming and transformed into a mixed-integer nonlinear programming (MINLP) formulation. A systematic solution approach is developed to solve the complex MINLP model and obtain better solutions with less computational effort.
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
(2021)
Article
Energy & Fuels
David A. Linan, Luis A. Ricardez-Sandoval
Summary: This work presents the optimal design and operation of catalytic distillation units using discrete and continuous design and operation variables combined with rigorous non-linear dynamic process models. The proposed optimization method, based on the Discrete-Steepest Descent Algorithm (D-SDA), allows for the simultaneous improvement of design and dynamic transitions. The case study on ethyl tert-butyl-ether (ETBE) production demonstrates that a single CD unit can be optimally designed to produce multiple ETBE grades and optimize its dynamic performance.
CHEMICAL ENGINEERING AND PROCESSING-PROCESS INTENSIFICATION
(2022)
Article
Engineering, Chemical
Vincent Kroeze, Lucas Braakhuis, Antoon J. B. ten Kate, Sascha R. A. Kersten
Summary: The paper presents a method for determining the minimum catalyst amount needed in a heterogeneously catalyzed reactive distillation column based on kinetic and VLE data, validated against literature cases. The method provides a conservative estimate for catalyst amount in the early design phase and information on column operability.
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
(2021)
Article
Engineering, Chemical
Shengkun Jia, Xing Qian, Xingwei Liu, Yiqing Luo, Xigang Yuan
Summary: This paper discusses methods to solve the problem of determining the optimal stage number in distillation column design. By relaxing integer stage numbers into continuous variables and using an interpolation function, the proposed model effectively avoids converging to non-integer stage numbers or poor optima.
CHEMICAL ENGINEERING SCIENCE
(2022)
Article
Engineering, Chemical
Yuyang Kang, Yiqing Luo, Xigang Yuan
Summary: The hybrid extraction-distillation process is more energy efficient than the pure distillation process. However, the current sequential iterative optimization method neglects the optimization of distillation column operating pressure, leading to suboptimal designs. In this study, a rigorous pseudo-transient tray model and a steady-state optimization algorithm were used to simultaneously optimize the column's structural parameters and operating conditions. Two case studies were conducted to validate the proposed method, and the results showed that considering product purity as inequality constraints in the optimization process expanded the search space and led to more economically favorable designs.
SEPARATION AND PURIFICATION TECHNOLOGY
(2022)
Article
Engineering, Environmental
Bor-Yih Yu, Ting-Yu Tseng, Zhen-Yu Yang, Shiau-Jeng Shen
Summary: This study evaluates different process configurations for producing solketal from glycerol and acetone, finding that the solvent-free coupled reaction/distillation (SFCRD) process is the most promising. The SFCRD process significantly reduces costs and CO2 emissions, while also establishing a control structure to handle disturbances effectively.
PROCESS SAFETY AND ENVIRONMENTAL PROTECTION
(2022)
Article
Engineering, Chemical
David A. Linan, David E. Bernal, Jorge M. Gomez, Luis A. Ricardez-Sandoval
Summary: This work presents the optimal synthesis and design of a rigorous catalytic distillation column by explicitly considering the multiscale and multiphase nature of the intensification process. A rate-based model and a discrete-steepest descent-based optimization framework are utilized to address intensive optimization problems. A case study involving the production of ethyl tert-butyl ether (ETBE) is discussed, showing the critical need to systematically consider multiscale and multiphase events for the optimal design of process intensification systems.
CHEMICAL ENGINEERING SCIENCE
(2021)
Article
Engineering, Chemical
Cesar Ramirez-Marquez, Eduardo Sanchez-Ramirez, Nima Nazemzadeh, Thomas Bisgaard, Juan Gabriel Segovia-Hernandez, Jens Abildskov, Seyed Soheil Mansouri
Summary: This study explores the dynamic and control behavior of dividing wall distillation columns using two different steady-state design approaches (molecular tracking and optimization method) for three different mixtures. The controllability of six design cases was evaluated using singular value decomposition, and the closed-loop performance was evaluated using integral absolute error in Aspen Dynamics. The results demonstrate that the side-draw location obtained by molecular tracking provides optimal controllability. Therefore, obtaining designs through the molecular tracking method has a slight advantage in control properties by reducing the time to find the optimal solution.
Article
Energy & Fuels
Cristopher A. Villegas-Uribe, Nancy Medina-Herrera, Javier A. Hernandez-Magallanes, Salvador Tututi-Avila
Summary: Sargent columns have been proven to significantly reduce energy consumption in chemical separations with four product streams. However, the operational concerns arise due to the number of vapor splits required to operate the system. Therefore, researchers have investigated simplified configurations to reduce vapor splits. The study examines the economic design and dynamic performance analysis of three simplified alternatives to the Sargent column for the separation of a BTX mixture. The optimized designs show attractive economic benefits, with savings of 26% to 33% in total annual cost compared to the conventional sequence. Furthermore, the simplified DWCs demonstrate suitable performance in dynamic settings, even without considering vapor splits as manipulated inputs.
CHEMICAL ENGINEERING AND PROCESSING-PROCESS INTENSIFICATION
(2022)
Article
Engineering, Chemical
Haiyan Tan, Lin Cong
Summary: Distillation columns are widely used in the petrochemical industry, but traditional mechanism modeling methods are not suitable for online optimization and control due to the complex structure and errors in simplified models. To address this, we establish a nonlinear dynamic model based on gas-liquid equilibrium theory to accurately characterize the distillation process. This model simplifies the structure compared to traditional mechanism models and provides a new approach to model-based methods for distillation columns, especially for efficient online models. Case studies demonstrate the high accuracy of the nonlinear model in concentration observation, and simulation results show that the control strategy based on this model outperforms traditional PID control.
Article
Engineering, Chemical
Jie Wu, Yiqing Luo, Xigang Yuan
Summary: In this paper, a new pseudo-transient (PT) nonequilibrium method based on the concept of pseudo-transient continuation approach is proposed. By decoupling the model equations, the steady-state solution of the nonequilibrium stage model can be obtained quickly and accurately, avoiding the issue of initial guess.
CHINESE JOURNAL OF CHEMICAL ENGINEERING
(2023)
Article
Computer Science, Interdisciplinary Applications
Tobias Seidel, Lena-Marie Raenger, Thomas Gruetzner, Michael Bortz
Summary: This paper presents a new approach to simulate and optimize multiple dividing wall columns simultaneously. By incorporating a subset of model equations as constraints and a subset of process variables as optimization variables, the optimization process becomes more stable and better solutions are obtained.
COMPUTERS & CHEMICAL ENGINEERING
(2022)
Article
Engineering, Chemical
Lixiao Ye, Nan Zhang, Guanghui Li, Dungang Gu, Jiaqi Lu, Yuhang Lou
Summary: This paper proposes a design methodology based on the GA-BP model to improve design efficiency, minimize reliance on experience, and obtain the best design solution. It establishes a distillation column surrogate model using the back propagation neural network technique and optimizes the design solution using a Genetic Algorithm with the minimum Total Annual Cost (TAC) as the objective function. The proposed method is verified with a propylene distillation column and achieves a 6.1% reduction in TAC and a 27.13 kgCO(2)/t reduction in carbon emission compared to the original design.
Article
Engineering, Chemical
Hao-Yeh Lee, Ming-Hung Yeh, Yu-Ying Chen, Cheng-Liang Chen
Summary: This study proposes a systematic method for separating six products from the EDA plant and minimizing the total cost. By optimizing the pressure-swing distillation configuration and fluid purity, significant cost savings can be achieved through energy-saving strategies such as external and internal heat integration.
SEPARATION AND PURIFICATION TECHNOLOGY
(2022)
Article
Engineering, Chemical
Xing Qian, Kuan-Han Lin, Shengkun Jia, Lorenz T. Biegler, Kejin Huang
Summary: This study develops nonlinear model predictive control (NMPC) schemes to control three-product DWCs, which are practical, effective, and promising technologies for distillation process intensification. Due to the strong interactivity and high nonlinearity of these systems, NMPC may be more suitable than traditional PI control. The model is established using Python and Pyomo platforms, and index reduction is used to avoid a high-index differential-algebraic equation (DAE) system. Case studies show that NMPC performs well in separating ethanol (A), n-propanol (B), and n-butanol (C) mixtures with small deviations and short settling times, demonstrating its feasibility and effectiveness for controlling three-product DWCs.
Review
Biotechnology & Applied Microbiology
Albert E. T. Rangel, Jorge Mario Gomez Ramirez, Andres Fernando Gonzalez Barrios
BIOFUELS BIOPRODUCTS & BIOREFINING-BIOFPR
(2020)
Article
Computer Science, Interdisciplinary Applications
David A. Linan, David E. Bernal, Luis A. Ricardez-Sandoval, Jorge M. Gomez
COMPUTERS & CHEMICAL ENGINEERING
(2020)
Article
Engineering, Multidisciplinary
Can Li, David E. Bernal, Kevin C. Furman, Marco A. Duran, Ignacio E. Grossmann
Summary: The study introduces a new algorithm for addressing nonconvex two-stage stochastic programming problems with any continuous or discrete probability distributions. The algorithm uses internal sampling and iterations between solving mixed-integer linear programming master problems and nonconvex nonlinear programming subproblems to obtain optimal solutions. In practice, an algorithm with confidence intervals is proposed to estimate sample sizes and update them dynamically during iterations.
OPTIMIZATION AND ENGINEERING
(2021)
Article
Biotechnology & Applied Microbiology
Albert Enrique Tafur Rangel, Luis H. Reyes, Jorge Mario Gomez Ramirez, Andres Fernando Gonzalez Barrios
Summary: The development of a culture medium is crucial for bioprocesses involving microorganisms for bioconversion of by-products, with computational methods playing an important role in identifying cellular requirements. This study proposed a computational approach to optimize glycerol consumption in Escherichia coli, resulting in increased growth and uptake rates when supplementing the medium with nitrogen and phosphorus compounds.
BIOFUELS BIOPRODUCTS & BIOREFINING-BIOFPR
(2021)
Article
Engineering, Chemical
David A. Linan, David E. Bernal, Jorge M. Gomez, Luis A. Ricardez-Sandoval
Summary: This work presents the optimal synthesis and design of a rigorous catalytic distillation column by explicitly considering the multiscale and multiphase nature of the intensification process. A rate-based model and a discrete-steepest descent-based optimization framework are utilized to address intensive optimization problems. A case study involving the production of ethyl tert-butyl ether (ETBE) is discussed, showing the critical need to systematically consider multiscale and multiphase events for the optimal design of process intensification systems.
CHEMICAL ENGINEERING SCIENCE
(2021)
Article
Engineering, Multidisciplinary
Qi Chen, Emma S. Johnson, David E. Bernal, Romeo Valentin, Sunjeev Kale, Johnny Bates, John D. Siirola, Ignacio E. Grossmann
Summary: This article introduces three core principles for engineering-oriented integrated modeling and optimization tool sets, and explains how Pyomo.GDP for Generalized Disjunctive Programming (GDP) advances this vision. By implementing a new logical expression system and two logic-based global optimization solvers on Pyomo.GDP, it improves the handling of logical constraints in nonlinear network design problems. The flexible array of solution paths available to GDP models and the new library of GDP models demonstrate the value of multiple solution approaches.
OPTIMIZATION AND ENGINEERING
(2022)
Article
Biotechnology & Applied Microbiology
Albert E. Tafur Rangel, Abel Garcia Oviedo, Freddy Cabrera Mojica, Jorge M. Gomez, Andres Fernando Gonzalez Barrios
Summary: This study focuses on analyzing the production of succinic acid from glycerol through computational methods for strain design and determining the effects on recovery and purification processes. The integration of metabolic phenotype of different mutants into recovery and purification processes achieved high recovery rates and molar purity levels. The most important factors in strain engineering were identified as productivity and growth rate.
BIOCHEMICAL ENGINEERING JOURNAL
(2022)
Article
Quantum Science & Technology
Rodolfo Quintero, David Bernal, Tamas Terlaky, Luis F. Zuluaga
Summary: Quantum devices have the potential to efficiently solve constrained combinatorial optimization problems. This study focuses on the maximum k-colorable subgraph problem as an important example. Two QUBO reformulations for this problem are derived and the range of penalty parameters are characterized. Numerical tests show the benefits and numerical power of using these reformulations and the latest quantum annealing devices.
QUANTUM INFORMATION PROCESSING
(2022)
Article
Engineering, Chemical
David E. Bernal, Akshay Ajagekar, Stuart M. Harwood, Spencer T. Stober, Dimitar Trenev, Fengqi You
Summary: This article provides an overview of quantum computing, its potential applications in the field of chemical engineering, including computational chemistry, optimization, and machine learning. The article discusses the potential advantages and challenges of quantum computing compared to classical computing and invites colleagues to join in the adoption and development of quantum computing.
Article
Engineering, Chemical
Fernando Calvo, Jorge M. Gomez, Oscar Alvarez, Luis Ricardez-Sandoval
Summary: This study presents a multiscale approach to evaluate the influence of emulsification on the macroscopic and microscopic properties of cosmetic emulsions. The results show that the impeller pumping capacity and tip velocity are key parameters in controlling the energy demand, drop formation, and microscopic structure of the emulsions.
CHEMICAL ENGINEERING RESEARCH & DESIGN
(2022)
Article
Operations Research & Management Science
David E. Bernal, Zedong Peng, Jan Kronqvist, Ignacio E. Grossmann
Summary: In this work, the authors extend the regularization framework and develop a regularized single-tree search method to solve convex mixed-integer nonlinear programming problems. The proposed approach, called Regularized Outer-Approximation, shows clear advantages over alternative methods in terms of computational results.
JOURNAL OF GLOBAL OPTIMIZATION
(2022)
News Item
Physics, Multidisciplinary
David Bernal Neira
Summary: Using quantum annealer for simulating phase transition dynamics is a crucial step towards quantum simulation and optimization, showcasing the capability of superconducting quantum devices in handling large-scale systems.
Article
Engineering, Chemical
Lijie Su, David E. Bernal, Ignacio E. Grossmann, Lixin Tang
Summary: This work aims to solve the integrated optimization problem for a complete refinery, considering the scheduling for crude oil operations, refinery planning, and blending operations. A novel hierarchical hybrid continuous-discrete time re-presentation is proposed to solve the integrated optimization problem. The computational results demonstrate the feasibility, validity, and capability of the proposed integrated model for obtaining near-optimal solutions.
CHEMICAL ENGINEERING RESEARCH & DESIGN
(2023)
Article
Operations Research & Management Science
Jadier Aristizabal, Maria del Mar Prieto, Lizzet Vargas, Diego Pradilla, Jorge M. Gomez
Summary: This study presents a multi-period nonlinear programming approach for optimal long-term oilfield production planning based on a two-phase, one-dimensional, and Cartesian-coordinated phenomenological reservoir model. The phenomenological model uses second-order partial differential equations approximated by a collocation on finite element method. This innovative approach integrates phenomenological models as mathematical constraints in the optimization problem and solves it using long-term production planning coupled with a simultaneous strategy, leading to the economic impact of considering constraints and state variables evolution for optimal long-term production planning.
JOURNAL OF OPTIMIZATION THEORY AND APPLICATIONS
(2023)
