Synthesis of optimal serial reactor structures for homogeneous reactions. Part I: Isothermal reactors (original) (raw)

Synthesis of optimal serial reactor structures for homogeneous reactions. I: Isothermal reactors.―II: Nonisothermal reactors

Aiche Journal, 1985

The reactor synthesis problem can simply be stated as follows: Given the reaction mechanism and kinetics, what is the optimum type and arrangement of the reactor(s) that would maximize product yield? Extensive studies for simple reaction systems (series, parallel, consecutive, etc.) using idealized plug flow and continuous stirred tank reactors have been presented in the literature. However, these studies fail to provide a systematic procedure for selecting the reactor(s) type and the arrangement for complex reaction schemes.

Chemical Reactor Analysis and Design Froment G.F. Bischoff K.B.

This book provides a comprehensive study of chemical reaction engineering, beginning with the basic definitions and fundamental principles and continuing a11 the way to practical application. It emphasizes the real-world aspects of chemical reaction engineering encountered in industrial practice. A rational and rigorous approach, based on mathematical expressions for the physical and chemical phenomena occurring in reactors, is maintained as far as possible toward useful solutions. However, the notions of calculus, differential equations, and statistics required for understanding the material presented in this book do not extend beyond the usual abilities of present-day chemical engineers. In addition to the practical aspects, some of the more fundamental, often more abstract, topics are also discussed to permit the reader to understand the current literature. The book is organized into two main parts: applied or engineering kinetics and reactor analysis and design. This allows the reader to study the detailed kinetics in a given "point," or local region first and then extend this to overall reactor behavior. Several special features include discussions of chain reactions (e.g., hydrocarbon pyrolysis), modem methods of statistical parameter estimation and model discrimination techniques, pore diffusion in complex media, genera1 models for fluid-solid reactions, catalyst deactivation mechanisms and kinetics, analysis methods for chemical processing aspects of fluid-fluid reactions. design calculations for plug flow reactors in realistic typical situations (e.g., thermal cracking), fixed bed reactors, fluidized be'd reactor design, and multiphase reactor design. Several of these topics are not usually covered in chemical reaction engineering texts, but are of high current interest in applications. Comprehensive and detailed examples are presented, most of which utilize real kinetic data from processes of industrial importance and are based on the authors' combined research and consulting experience. We firmly believe, based on our experience, that this book can be taught to both undergraduate and graduate classes. If a distinction must be made between undergraduate and graduate material it should be in the extension and the depth of coverage of the chapters. But we emphasize that to prepare the student to solve the problems encountered in industry, as well as in advanced research, the approach must be the same for both levels: there is no point in ignoring the more complicated areas that d o not fit into idealized schemes of analysis.

Reactor network synthesis for isothermal conditions = Síntese de redes de reatores para condições isotérmicas

In the present paper, a computational systematic procedure for isothermal Reactor Network Synthesis (RNS) is presented. A superstructure of ideal CSTR and PFR reactors is proposed and the model is formulated as a constrained Nonlinear Programming (NLP) problem. Complex reactions (series/parallel reactions) are considered. The objective function is based on yield or selectivity, depending on the desired product, subject to different operational conditions. The problem constraints are mass balances in the reactorsand in the considered reactor network superstructure. A systematic computational procedure is proposed and a Genetic Algorithm (GA) is developed to obtain the optimal reactor arrangement with the maximum yield or selectivity and minimum reactor volume. Results are as good as or better than those reported in the literature. No presentetrabalho apresenta-se um procedimento computacional para síntese de redes de reatores (SRR) operando em condições isotérmicas. Uma superestrutur...

Systematic staging in chemical reactor design

2010

The foundation and implementation of a method for systematic reactor design is described. The reactor path is sectioned into stages where each stage is designed so as to optimize an overall objective. This is a further development of a previously proposed method for designing chemical reactors . Reactants pass through a series basic operations or functions to form the desired products. The basic operations are represented by design functions on the path volume. The design functions are fluid mixing (dispersion), distribution of extra feed points, distribution of heat transfer area and coolant temperature, catalyst dilution distribution and more. The conceptual reactor design problem is solved as an optimal control problem. A direct method is applied where both the design functions and the state variables are discretized. The realization of the optimization is a staged process string of multifunctional units. A kinetic model of the gas phase methanol synthesis is used as an example. By applying the method on the model, a staged reactor design with less heat transfer area and higher production is possible.