Principles of Chemical Engineering Processes

UAE University, Al-Ain, United Arab Emirates Laurentian University, Sudbury, Ontario, Canada

Introduction


At the End of This Chapter You Should Be Able to


Definition of Chemical Engineering


Material and Energy Balances


Values, Units, and Dimensions


Systems of Units


Unit Conversion


Time


Mass


Length


Volume


Density


Force


Pressure


Energy


Power


Weight


Dimensional Homogeneity


Significant Figures


Multiplication and Division


Addition and Subtraction


Process and Process Variables


Density, Mass, and Volume


Flow Rate


Moles and Molecular Weight


Mass Fraction and Mole Fraction


Concentration


Pressure


Types of Pressure


Manometers for Pressure and DP Measurement


Temperature Measurement


Converting Temperatures


Ideal Gas Law


Standard Temperature and Pressure


Process Classification


Problems


Process Classification


Types of Processes


Unit Conversion


Flowrate through Horizontal Pipe


Molar Flow Rate


Dimensional Homogeneity


Calculation of Mass for Specific Gravity and Volume


Convert of Equation to Other Units


Further Readings


Process Units and Degrees of Freedom Analysis


At the End of This Chapter You Should Be Able to


Degree of Freedom Analysis


Possible Outcomes of the DFA


Sources of Equations


Process Units: Basic Functions


Divider=Splitter


Mixer (Blender)


Dryer (Direct Heating)


Filter


Distillation Column


Evaporator


Dehumidification


Humidifier


Leaching and Extraction


Absorption (Gas Absorption) Desorption


Partial Condenser


Flash Vaporizer and Flash Distillation


Crystallizer


Reactors (Chemical Reactor, Combustor, Furnace, and Reformer)


Batch Reactor


Plug Flow and Packed Bed Reactor


Continuous Stirred Tank Reactor and Fluidized Bed Reactor


Summary of Degree of Freedom Analysis


Problems


Absorption of Acetone from Air


Separation of Liquid Mixture


Absorber–Stripper Process


Filtration Processes


Evaporation Processes


Further Readings


Material Balance in Single Unit Processes


At the End of This Chapter You Should Be Able to


General Material Balance Equation


Material Balance Simplifications


Flowcharts


Note on Notation


Problems Involving Material Balances on a Single Unit


Material Balance Fundamentals


Classification of Processes


Based on How the Process Varies with Time


Based on How the Process was Designed to Operate


Types of Balances


Stream Specifications


Scaling


Basis for Calculation


Basis for Calculation


Method for Solving Material Balance Problems


Material Balance on Bioprocesses


Problems


Separation of Ethanol–Methanol Process Stream


Wet Leather Drying Process


Separation of Ethanol–Methanol–Propanol Mixture


Ethanol–Water Separation


Mixing of Hydrochloric Acid with Water


Removal of Acetone from Nitrogen Using an Absorber


Separation of Benzene=Toluene Mixture


Dilution of Methanol Mixture


Humidification Chamber


Absorption of Water from a Gas Mixture


Drying of Wet Sugar


Further Readings


Multiple-Unit Process Calculations


At the End of This Chapter You Should Be Able to


Multiple-Unit Process Calculations


Recycle, Bypass, Makeup, and Purge


Recycle


Bypass


Purge


Makeup


Problems


Separations of Benzene, Toluene, Xylene Mixtures


Filtration Processes


Concentration of Orange Juice


Separation of NaCl and KCl Mixture


Sulfur Removal System


Separation of DMF–Nitrogen Mixture


Separation of Benzene–Toluene Mixture


Separation of Potassium Nitrate


Production of Instant Coffee


Further Readings


Material Balances in Reactive Processes


At the End of This Chapter You Should Be Able to


Amount of Substance in Moles


Why Use the Mole?


General Material Balance


Differential Balance


Integral Balance


Stoichiometry Basics


Stoichiometric Equation


Stoichiometric Coefficients (ni)


Stoichiometric Ratio


Limiting and Excess Reactants


Fractional Conversion


Methods of Solving Material Balances Involving Chemical Reactions


Extent of Reaction Method


Element or Atomic Balance Method


Molecular or Component Balance Approach


Multiple Reactions and Extent of Reaction


Degree of Freedom Analysis for Reactive Processes


Molecular Species Balances and Extent of Reaction


Atomic Species Balances


Independent Chemical Reactions


Independent Species Balances


Chemical Equilibrium


Combustion Reactions


Theoretical and Excess Air


Problems


Incomplete Combustion of Butane


Complete Combustion of Butane


Methane Combustion


Burning Ethyl Ketone with Excess Air


Roasting of Iron Pyrite


Water–Gas Shift Reaction


Production of Sulfuric Acid


Further Readings


Multiple Systems Involve Reaction, Recycle, and Purge


At the End of This Chapter You Should Be Able to


Reaction with Product Separation and Recycle


Reaction with Recycle and Purge


Flowsheet for Reaction with Recycle


Flowsheet for Reaction with Recycle and Purge


Reaction and Multiple-Unit Steady-State Processes


Auxiliary Relationship


Problems


Chemical Reactor Analysis


Laundry Detergent Synthesis Process


Butanol Production


Hydrodealkylation Process


Uranium and Zirconium as Nuclear Fuels


Further Readings


Energy Balance without Reaction


At the End of This Chapter You Should Be Able to


Enthalpy and Energy Balances


How Does Energy Move Across Systems?


Forms of Energy


Kinetic Energy (Ek)


Potential Energy (Ep)


Internal Energy (U)


Intensive versus Extensive Variables


Transfer of Energy


First Law of Thermodynamics


Energy Balances on Closed Systems


Possible Simplifications on Energy Balance in a Closed System


Energy Balances in Open Systems at Steady State


Possible Simplifications on Energy Balance in an Open System


Enthalpy Calculations


Reference States and State Properties


Use of Linear Interpolation in Steam Tables


Enthalpy Change in Nonreactive Processes


Enthalpy Change as a Result of Temperature Change


Enthalpy Change because of Phase Changes


Enthalpy Change because of Mixing


Energy Balance on Bioprocesses


Psychrometric Chart


Summary on Energy Balances without Reactions


Problems


Vaporization of Liquid Methanol


Heating of Propane


Expansion of Wet Steam


Open System Energy Balance (Heating of Methanol)


Open System Energy Balance (Heating of Liquid Methanol)


Vaporization of Liquid n-Hexane


Closed System Energy Balance (Heating of Acetone)


Open System Energy Balance (Power Output of Turbine)


Open System Energy Balance (Power Requirement of Compressor)


Further Readings


Energy Balances with Reaction


At the End of This Chapter You Should Be Able to


Introduction


Heats of Reaction


Heats of Reaction Using the Extent of Reaction


Notes on Heats of Reaction


Reactions in Closed Processes


Measurement of Heats of Reaction


Hess’s Law


Calculating Heat of Reaction () from Heats of Formation


Calculating D Hr from Heats of Combustion


Energy Balances on Reactive Processes


Heat of Reaction Method


Heat of Formation Method: Process Path


General Procedure for Energy Balances with Reaction


Processes with Unknown Outlet Conditions


Energy Balances in Bioprocess


Problems


Estimation of Heat of Reaction


Production of Superheated Steam


Ammonia Synthesis Process


Catalytic Transalkylation of Toluene to Benzene


Combustion of Methane


Anaerobic Yeast Fermentation


Further Readings


Combined Material and Energy Balances


At the End of This Chapter You Should Be Able to


Material Balances


Conversion


Yield


Selectivity


Extent of Reaction ()


Energy Balances


Heat of Reaction Method


Heat of Formation Method


Concept of Atomic Balances


Mathematical Formulation of the Atom Balance


Degree of Freedom Analysis for the Atom Balance


Implementing Recycle on the Separation Process


Problems


Mixing of Hot and Cold Ethanol


Combustion of Acetylene


Dehydrogenation of Ethanol


Independent Chemical Reaction


Cumene Synthesizes Process


Dehydrogenation of Propane


Further Readings


Unsteady-State Material and Energy Balances


At the End of This Chapter You Should Be Able to


Unsteady-State Material Balance


Unsteady-State Energy Balance


Problems


Fluid Flow from Storage Tank


Boiling of Water


Heating Using Saturated Steam


Heating a Solvent in a Stirred Tank


Concentration of Reactant as a Function of Time


Further Readings


Appendix


Index