化工原理英文教材传质分离过程Mass Transfer and Separation Processes

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•How to separate a solution of salt and water?
(Problem for producing fresh water from the sea.) (1)Supply heat and boil water off; (2)Supply refrigeration and freeze out pure ice; (3)Pump the water to a higher pressure and force it through a thin solid membrane that will let water through preferentially to salt (reverse osmosis)反渗透.
•Thinking (introspection): Many environmental pollution problems are caused by separation itself?
Why? How to solve this problem?
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3. Definition of Separation Processes
Product Streams (different in composition, at least 2 streams)
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Example: Distillation Fractionating
column
Feed
Overhead product
Bottom product
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•The separation is caused by the addition of a separating agent）. •separating agent: matter or energy •Usually the separating agent will cause the formation of a second phase of matter. • •Separation methods(mass transfer between two immiscible phases):
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3. Learning Approaches
Mainly Learning: 1)process principles; 2)structure of typical equipment; 3)design calculations; 4)selection of typical equipment; 5)operating methods; 6)enhancement of unit operations.
化工原理 Principles of Chemical Industry
1. About the Courses and time scheduling
Lecturing (theory)： About the Experiments(Contents, methods, groups)： Course Design： What is the text book? Unit Operations of Chemical Engineering, the sixth edition. It is most popular in Chem. Eng. in USA univ. Authors? Warren L. McCabe, Julian C. Smith and Peter Harriott.
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3. Learning Approaches
For each of the unit operations, mainly learning the follow 1)Material balances; 2)Energy/Enthalpy balances; 3)Equilibria; 4) Heat and Mass transfer rates; 5)Operation relationships.
O2
Capbvilelosblvosaleedoslrvoseyedlssel
Blood Flow(High conc.of CO2)
CO2 O2ຫໍສະໝຸດ Blood Flow(low
CO conc.of CO2) 2
O2
Capillabrylood blood vessel v essel
Blood Flow Blood Vessel
•1)Forming a second phase of matter;
•2)Utilizing differences in some property such as vapor pressure, solubility or diffusivity…
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7. TERMINOLOGY AND SYMBOLS
Industrial processes: A group of operations for separating the components of mixtures is based on the transfer of material from one homogeneous phase to another.
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3. Learning Approaches
Preparing lessons or preview before class →Review Don't take the course just for the grade. Practice makes a master. If you don't practice, you won'
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Introduction
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1. An Example of Mass Transfer: Respira
CO2
Breathe in: O2; Breathe out: CO2
COCOC2 OO2 2
2O2 O2 Capillary
Lung
CO2 O2 CaCpialplbaillorlyoadry
•All three approaches are the reverse procedure of mixing, or “unmixing” , or separation processes.
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•Spontaneous processes: randomness ↑ •Separation processes: randomness ↓ •Definition of separation processes: those operations which transform a mixture of substances into two or more products which differ from each other in composition.将物质在
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2. Grading Standard (Continued)
《Experiments of Chem Eng Principles》： Final Exam(Including last semester’)：80% Participation(including attendance, Assignments) ：20% （ Participation of last semester ：20%） Design Experiment？（Encouraged, Cooperation permitt
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Other examples of mass transfer:
•A lump of sugar added to a cup of black coffee. •Water evaporates from ponds to increase the humidity of the passing air stream. •Perfume presents a pleasant fragrance which is imparted throughout the surrounding atmosphere.
•The second law of thermodynamics（第二热力学定律）: All natural processes take place so as to increase the entropy（熵）, or randomness of the universe. •Salt dissolves in water and forms a solution of uniform composition. (spontaneously, randomness ↑)
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2. Course Policies & Grading Standard
Final Exam of《 Mass Transfer and Separation Processes》 Participation(including attendance, Assignments) and Mid
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Other examples of Separation Processes : Food processing: •pharmaceutical manufacture. •Desalination of seawater. •Water and air pollution , municipal refuse (solid wastes) present separation problems of immense social importance.
membrane separations 3) Separation processes with chemical reaction
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6. General Separation process
Feed stream (one or more)
Separating agent （matter or energy）