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공개·회원 9명
John Jackson
John Jackson

A Comprehensive Guide to Unit Operations in Chemical Engineering: Principles of Unit Operations 2nd Ed by Foust et al.



- Who are the authors of the book "Principles of Unit Operations" and what are their credentials? - What are the main topics covered in the book and how are they organized? H2: Stage Operations - What are mass transfer operations and how do they involve equilibrium stages? - How to perform equilibrium stage calculations for binary and multicomponent systems? - What are countercurrent multistage operations and how to design them with or without reflux? - What are some simplified calculation methods for multistage operations? H2: Molecular and Turbulent Transport - What are the molecular transport mechanisms of mass, heat, and momentum? - How to apply differential and integral balances to transport problems? - What are the equations of change for transport phenomena? - What is turbulent transport and how to model it? - What are the fundamentals of transfer coefficients and interphase transfer? H2: Applications to Equipment Design - How to apply heat transfer principles to design heat exchangers, condensers, evaporators, etc.? - How to apply mass transfer principles to design absorption, distillation, extraction, etc.? - How to analyze simultaneous heat and mass transfer problems such as humidification, drying, evaporation, and crystallization? - How to apply the energy balance to flow systems and fluid motive devices? - How to handle particulate solids and their flow and separation through fluid mechanics? H1: Conclusion - What are the main takeaways from the book "Principles of Unit Operations"? - How does the book help chemical engineers to understand and solve practical problems in their field? - What are some limitations or challenges of the book and how can they be overcome or improved? H1: FAQs - Q1: What is the difference between unit operations and unit processes? - Q2: What are some examples of unit operations in different industries? - Q3: What are some advantages and disadvantages of using simplified calculation methods for multistage operations? - Q4: What are some factors that affect the choice of heat transfer equipment? - Q5: What are some applications of simultaneous heat and mass transfer in food processing? # Article with HTML formatting Introduction




Unit operations are the basic steps or techniques used in chemical engineering to transform raw materials into products. They involve physical changes such as separation, mixing, heating, cooling, etc., without altering the chemical composition of the substances involved. Unit operations are essential for designing, analyzing, and optimizing chemical processes and plants. They also help chemical engineers to understand the underlying principles of transport phenomena, thermodynamics, kinetics, and reaction engineering.




principles of unit operations 2nd ed foust



One of the most influential books on unit operations is "Principles of Unit Operations" by Alan S. Foust, Leonard A. Wenzel, Curtis W. Clump, Louis Maus, and L. Bryce Andersen. The book was first published in 1955 and has been revised several times since then. The second edition was published in 1980 and is still widely used as a reference text by students and professionals alike. The authors of the book are all distinguished professors or researchers in chemical engineering who have made significant contributions to their field.


The book covers a wide range of topics related to unit operations, such as stage operations, molecular and turbulent transport, and applications to equipment design. The book is organized into four parts: Part I deals with stage operations such as mass transfer operations, phase relations, equilibrium stage calculations, countercurrent multistage operations, etc.; Part II deals with molecular and turbulent transport such as molecular transport mechanisms, differential and integral balances, equations of change, turbulent transport mechanisms, etc.; Part III deals with applications to equipment design such as heat transfer, mass transfer, simultaneous heat and mass transfer problems, energy balance in flow systems, fluid motive devices, etc.; Part IV deals with particulate solids such as flow and separation through fluid mechanics. The book also includes numerous examples, problems, tables, figures, and references to help the reader understand and apply the concepts and methods presented.


Stage Operations




Stage operations are unit operations that involve the transfer of mass or energy between two or more phases that are in contact with each other. Examples of stage operations are distillation, absorption, extraction, leaching, adsorption, etc. These operations are based on the concept of equilibrium stages, which are hypothetical zones where the phases are in equilibrium with each other. The number of equilibrium stages required to achieve a desired separation or conversion depends on the operating conditions, the properties of the phases, and the design of the equipment.


The book explains how to perform equilibrium stage calculations for binary and multicomponent systems using various methods such as graphical, algebraic, and numerical methods. The book also shows how to design countercurrent multistage operations with or without reflux using the McCabe-Thiele method, the Ponchon-Savarit method, the Lewis-Matheson method, etc. The book also discusses some simplified calculation methods for multistage operations such as the Fenske-Underwood-Gilliland method, the Kremser-Brown method, the Edmister method, etc. These methods are useful for estimating the number of stages or the minimum reflux ratio without solving rigorous equations.


Molecular and Turbulent Transport