Mass transfer and separation technology Massöverföring och separationsteknik ( MÖF-ST ) , 7 sp (~187 h)

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1 Course 2016 = last course as 7 sp As of : courses = 5 sp = 5 sp Mass transfer and separation technology Massöverföring och separationsteknik ( MÖF-ST ) , 7 sp (~187 h) 1. Introduction Ron Zevenhoven Åbo Akademi University Thermal and Flow Engineering Laboratory tel ; ron.zevenhoven@abo.fi 1.1 Course content 2

2 Course management year 2016 Lectures & old exams by Ron Zevenhoven 23 x 2h Exercises with course assistents 5 x 2h Until the next exam, 3x2 home-work exercises (will be corrected by the course assistents) give 6 p. in addition to a 13 p. also otherwise passed exam (max = 30 p.) Next exam 27.5/15, after that sommartent in June and a few exams Note: ½-way exam Mass transfer! Course material: overhead sheet material via compendium Massöverföring by Göran Öhman (1996) exercise handouts etc. In the course library: 10 copies of the book Separation process principles by J.D. Seader & E.J. Henley (Wiley, 2006) 3 Course assistants & homework 2016 (Axelia I, 3rd floor) MSc Evelina Koivisto evelina.koivisto@abo.fi DI Martin Slotte martin.slotte@abo.fi MSc Daniel Legendre dlegendr@abo.fi DI Rickard Erlund rerlund@abo.fi 4

3 Contents of course Principles and definitions, diffusion Phase equilibrium Mass transfer coefficients, Boundary layers Dimensional analysis, Heat / mass transfer analogy Convective mass transfer New 2006: Mass transfer with chemical reaction Introduction to separation processes Batch distillation, Continuous distillation Absorption/desorption, Packed tower columns New 2007: Extraction and leaching New 2007: Membranes (from Transport processes 3316) New 2007: Mixing and blending Examples of mass transfer and separation processes (mainly G/G, G/L, L/L) 6

4 Some mass transfer processes /1 Drying Extraction 7 Some mass transfer processes /2 Convection Bubble growth (combined heat and mass transfer) 8

5 Some mass transfer processes /3 Separation funnel Osmosis 9 Some mass transfer processes /4 Distillation 10

6 Some mass transfer processes /5 1. Diffusion-in of reactants through boundary layer 2. Adsorption of reactants on the substrate 3. Chemical reaction takes place 4. Desorption of absorbed species 5. Diffusion out of by-products Mass transfer before and after chemical reaction Dispersion of smoke in the atmosphere 11 Some mass transfer processes /6 Mixing 12

7 Mass transfer and separation processes Reactants pre - treatment Reactor Products treatment Upgrading and mixing of (some) reactants and additives before the reactor Contacting of reactants in reactor Separation of valuable products, by-products and unused reactant (reflux) This course: analyses and designs are based on mass balances and (deviations from) thermodynamic equilibrium 13 Separation process examples Drying of a solid, using heat or dry gas Adsorption of gas or liquid, using a solid Distillation, using heat to create a vapour phase Gas absorption, using a liquid absorbent Stripping, using a gaseous absorbent Extraction of liquid or solid, using a solvent that creates immiscible phases Crystallisation, using cooling to create a solid phase Separation processes to be considered in this course are mainly those that involve addition or creation of a new phase. This excludes mechanical separation methods that use a barrier (filters), and those that use an external field or gradient (gravity, electromagnetic). see for example Advanced Course

8 Terminology Typically a V phase is added or created in order to separate (something from) the L phase. V phase is usually the more volatile of L and V phases source: MSH93 15 Sources #1 MSH93 W.L. McCabe, J.C. Smith. P. Harriott Unit operations of chemical engineering 5th ed. McGraw- Hill (1993) SH06 J.D. Seader, E.J Henley Separation process principles John Wiley, 2nd edition (2006) T68 R.E. Treybal Mass transfer operations McGraw- Hill 2nd edition (1968) Ö96 G. Öhman Massöverföring Åbo Akademi Värmeteknik (1996) 2.3 Recommended: (cheap ~20 US$ reprint of Nov of book from 1980): Separation Processes: Second Edition Paperback by C. J. King 16