Transport Processes and Separation Process Principles

Citation

Geankoplis, C. J., Hersel, A. A., & Lepek, D. H. (2018). Transport Processes and Separation Process Principles (5th ed.). Pearson.

Chapter Summary

The fifth edition is a substantial reorganization. The preface explains that the earlier fourteen long chapters were split into thirty-three shorter ones to resemble current transport phenomena and separations texts, while the content itself changed relatively little. The book now runs to about 1,250 pages: Part 1, Transport Processes (Chapters 1–21), Part 2, Separation Process Principles (Chapters 22–33), and property appendices. Every chapter opens with a list of objectives and closes with a chapter summary; worked examples are numbered by section, and further homework problems are posted on the authors' companion website.

Chapter 1: Introduction to Engineering Principles and Units

A review chapter: the classification of transport processes and separation processes (unit operations), SI, cgs and English units, temperature and composition, gas laws and vapor pressure, material balances with recycle and reaction, energy units, heat balances, and numerical integration by Simpson's rule. The preface states that readers who already know this material may omit all or part of it.

Chapters 2–4: Introduction to Fluids and Fluid Statics; Fluid Properties and Fluid Flows; Overall Mass, Energy, and Momentum Balances

Fluid statics and manometers, Newton's law of viscosity and the Reynolds number come first. Chapter 4 then develops the overall (macroscopic) mass, energy and momentum balances, including the mechanical-energy balance and Bernoulli equation, and closes with shell momentum balances that give laminar velocity profiles in a pipe and a falling film.

Chapters 5–7: Incompressible and Compressible Flows in Pipes; Flows in Packed and Fluidized Beds; Pumps, Compressors, and Agitation Equipment

The engineering core of fluid mechanics: friction factors and fitting losses, pipe sizing, isothermal and adiabatic compressible flow, and flow meters from the Pitot tube to weirs; drag on immersed objects, packed beds and fluidization; and pumps, gas-moving machinery, compression, and the design, power and scale-up of agitated vessels.

Chapters 8–11: Differential Equations of Fluid Flow; Non-Newtonian Fluids; Potential Flow and Creeping Flow; Boundary-Layer and Turbulent Flow

The more theoretical fluid mechanics. Chapter 8 derives the differential equations of continuity and motion and applies them to simple flows. Chapter 9 extends pipe-flow and agitation calculations to non-Newtonian fluids. Chapter 10 introduces the stream function, inviscid potential flow and creeping flow, and Chapter 11 treats boundary layers, turbulence, Reynolds stresses, the Prandtl mixing length and the universal velocity distribution.

Chapters 12–14: Introduction to Heat Transfer; Steady-State Conduction; Principles of Unsteady-State Heat Transfer

Chapter 12 introduces conduction, convection and radiation and repeats the energy-unit and heat-balance material from Chapter 1. Chapter 13 covers steady conduction through composite walls, cylinders and spheres, internal heat generation, shape factors and finite differences. Chapter 14 handles transient conduction by lumped, analytical, chart and numerical methods, with a section on chilling and freezing foods.

Chapters 15–17: Introduction to Convection; Heat Exchangers; Introduction to Radiation Heat Transfer

Chapter 15 uses dimensional analysis and boundary-layer ideas to build convection correlations for pipes, external flows, natural convection, boiling and condensation, and special cases such as agitated vessels and finned exchangers. Chapter 16 is a short chapter on exchanger types, LMTD correction factors, effectiveness, fouling and the double-pipe exchanger. Chapter 17 develops view factors, gray bodies and radiation in absorbing gases.

Chapters 18–21: Introduction to Mass Transfer; Steady-State Mass Transfer; Unsteady-State Mass Transfer; Convective Mass Transfer

Chapter 18 sets out Fick's law, the estimation of diffusion coefficients and the equation of continuity for a binary mixture. Chapter 19 covers steady diffusion in gases, liquids, solids, porous media (including Knudsen diffusion) and biological gels; Chapter 20 treats transient diffusion and diffusion with reaction; Chapter 21 develops mass-transfer coefficients and the analogies among the three transport processes.

Chapters 22–23: Absorption and Stripping; Humidification Processes

Chapter 22 sets up interphase equilibrium, stage contact and film and overall mass-transfer coefficients, then designs plate and packed absorption towers, including flooding, transfer units and heat effects. Chapter 23 covers humidity, the humidity chart and wet-bulb temperature, and the design of water-cooling and dehumidification towers.

Chapters 24–25: Filtration and Membrane Separation Processes (Liquid–Liquid or Solid–Liquid Phase); Gaseous Membrane Systems

Chapter 24 moves from dead-end filtration theory (constant-pressure and constant-rate) to microfiltration, ultrafiltration, reverse osmosis and dialysis, including hemodialysis in an artificial kidney. Chapter 25 is a detailed treatment of gas permeation, with complete-mixing, cross-flow, countercurrent and cocurrent models and a spreadsheet finite-difference method.

Chapters 26–27: Distillation; Liquid–Liquid Extraction

Chapter 26 covers vapor–liquid equilibrium, flash and batch distillation, the McCabe–Thiele method, tray efficiencies and tower diameter, the enthalpy–concentration method and multicomponent shortcut methods. Chapter 27 covers extraction equilibria, extraction equipment and countercurrent multistage design.

Chapters 28–31: Adsorption and Ion Exchange; Crystallization and Particle Size Reduction; Settling, Sedimentation, and Centrifugation; Leaching

Fixed-bed adsorption and ion exchange, crystallization theory and size reduction, settling, thickening, centrifuges and cyclones, and single-stage and countercurrent leaching.

Chapters 32–33: Evaporation; Drying

Chapter 32 covers evaporator types, single- and multiple-effect calculations, condensers, the evaporation of biological materials, and vapor recompression. Chapter 33, the longest in the book, covers dryer equipment, equilibrium moisture, constant-rate and falling-rate drying, equations for various dryers, freeze-drying, and the thermal processing and sterilization of biological materials.

Key Concepts

Part 1: Transport Processes

• Unit operations and transport processes: the book's organizing idea that diverse separation steps share three underlying mechanisms, momentum, heat and mass transfer.
• Overall balances and the Bernoulli equation: macroscopic mass, energy and mechanical-energy balances used to size piping, pumps and flow meters.
• Friction factor: the dimensionless link between flow rate and pressure drop in laminar and turbulent pipe flow.
• Equations of continuity and motion: the differential forms of mass and momentum conservation.
• Fick's law and diffusivity: the molecular flux of a species and how diffusion coefficients are estimated.
• Mass-transfer coefficients and analogies: correlations for convective mass transfer, related to heat and momentum transfer.

Part 2: Separation Process Principles

• Equilibrium stages and operating lines: the graphical and analytical basis for absorption, distillation, extraction and leaching design.
• McCabe–Thiele method: stepwise stage construction for binary distillation, with minimum and total reflux.
• Breakthrough curve: the outlet concentration history used to design fixed-bed adsorption and ion-exchange columns.
• Constant-rate and falling-rate drying: the two periods of a drying curve, each with its own calculation method.

Critical Analysis

Strengths

• Transport principles linked to equipment. The two-part plan, stated in the preface, puts the principles of momentum, heat and mass transfer first and the separation processes after, so a course can show how mass-transfer coefficients from Chapter 21 feed directly into the tower design of Chapter 22, or how the drying chapter draws on heat and mass transfer together.
• Breadth of separations. Part 2 covers twelve chapters of separations, including membrane processes (liquid and gas), adsorption and ion exchange, crystallization, sedimentation and leaching, alongside the classic distillation, absorption and extraction chapters.
• Bioprocess and food examples. The table of contents gives regular attention to biological materials: chilling and freezing of foods, diffusion in biological gels and of biological solutes, hemodialysis, evaporation of fruit juices and sugar solutions, freeze-drying, and sterilization kinetics.
• Built for flexible courses. The preface lays out five course plans (transport plus separations over three semesters, transport only, separations only, and so on), and the new short chapters with objectives and summaries make it easy to assign pieces.

Limitations

• Traces of the reorganization. Splitting the old chapters left some repetition: the sections on energy units and heat balances in Chapter 1 reappear as the first sections of Chapter 12, and the humidity material of Chapter 23 reappears in Chapter 33. The preface's fifth course plan, for mass transfer, still refers to Chapters 12–19, which in the new numbering are largely heat transfer.
• Uneven chapter sizes. Chapters 2, 3 and 16 run to roughly ten to seventeen pages each, while Chapters 22, 26 and 33 run to more than sixty; the new chapter count does not mean equal weekly units.
• Software is outside the book. The software-based problems for Aspen or CHEMCAD, MATLAB, COMSOL and Excel are on the companion website rather than in the printed chapters.

Where It Fits in the Course

In the chemical process engineering list the book sits between the first-year balances course and the senior design course. Felder, Rousseau and Bullard's Elementary Principles of Chemical Processes and Denn's short Chemical Engineering: An Introduction teach the material and energy balances that Geankoplis reviews in Chapter 1 and then assumes. McCabe, Smith and Harriott's Unit Operations of Chemical Engineering is its closest counterpart: both cover fluid flow, heat transfer and the main separation operations, and they can be read side by side. The difference is in organization: Geankoplis develops all the transport principles first, in Part 1, and only then turns to the separation processes, so it suits a course that teaches transport phenomena and separations as separate subjects.

Fogler's Elements of Chemical Reaction Engineering covers reactors, which this book does not treat beyond diffusion with reaction. Towler and Sinnott's Chemical Engineering Design comes last, drawing on the separation-unit calculations of Part 2 within whole-process and plant design.

How to Use This Book

The book is aimed at chemical engineering students in the junior and senior years and at students in other process fields, such as food and biological engineering. Readers need material and energy balances, basic thermodynamics, and calculus with ordinary differential equations; Chapters 8, 10, 11, 14 and 20 are the most mathematical.

Pick the course plan from the preface that matches the syllabus:

• Transport phenomena course (two semesters): Chapters 2–21, with Chapter 1 as optional review. Chapters 2–7 and 12–16 are the practical core; Chapters 8–11 add the differential and boundary-layer view and can be thinned in a first course; Chapters 18–21 are the mass-transfer core.
• Separations or unit operations course (one semester): start with Chapter 22's opening sections on equilibrium and interphase mass transfer, then Chapter 26 (distillation), the rest of Chapter 22 (absorption), and Chapter 27 (extraction). Add membranes, adsorption, evaporation or drying according to the program; food and bioprocess programs will want Chapters 32–33.
• Mass-transfer only: Chapters 18–21, followed by a selection from Part 2.

Use each chapter's objectives and summary as a check, work the numbered examples by hand before the problems, and use the companion website's software problems to practise solving the same models in Excel, MATLAB or a process simulator. Keep the appendices at hand for property data.