Event
0	European Conference on Mixing in the Chemical and Allied Industries, February 1977, Mons /B
1	6th International CHISA Congress, August 1978, Prague /CS
2	3rd European Conference on Mixing, April 1979, York /UK
3	Symposium on Transport Phenomena in Gas-Liquid Systems with Mixing, March 1980, Cologne /D
4	Symposium on Mechanical Mixing in Crystallizers, (organized together with the WP on Crystallization), April 1981, Erlangen /D
5	4th European Conference on Mixing, April 1982, Noordwijkerhout /NL
6	Symposium on Turbulence in Mixing, April 1983, Toulouse /F
7	Symposium on Mixing of Non-Newtonian Industrially Important Fluids  (organized together with WP on Non-Newtonian Liquid Processing)September 1984, Prague /CS
8	5th European Conference on Mixing, June 1985, Wrzburg /D
9	International Conference on Mixing, June 1986, Toulouse /F
10	Symposium on Mixing of Solid Suspensions, September 1987, Prague /CS
11	6th European Conference on Mixing, May 1988, Pavia /I
12	Symposium on Mixing and Reaction in Multiphase Systems (organized together with the WP on Chemical Reaction Engineering), April 1989, Aachen /D
13	Symposium on Mixing in Motionless Mixers, August 1990, Prague /CS
14	7th European Conference on Mixing, September 1991, Brugge /B
15	Workshop on Mixing and Chemical Reaction (a session of ISCRE 12), July 1992, Turin /I
16	Symposium on the Role of Micro-mixing in Reaction Engineering, Precipitation and Polymerization, August 1993, Prague /CZ
17	8th European Conference on Mixing, September 1994, Cambridge /UK
18	Symposium on Mechanical Aspects of Mixing, August 1996, Prague /CZ
19	9th European Conference on Mixing, March 1997, Paris /F
20	10th European Conference on Mixing, July 2000, Delft /NL
21	4th International Symposium of Mixing for Industrial Processes (ISMIP 4) May 2001, Toulouse /F
22	Symposium on Mixing of Suspensions, August 2002, Prague /CZ
23	11th European Conference on Mixing, October 2003, Bamberg/DE
24	5th International Symposium on Mixing for Industrial Processes (ISMIP 5) June 2004, Sevilla /SP
25	10th Jubilee Polish Seminar On Mixing And International Workshop, 26-29 September 2005, Pozna/Poland
26	Fluid Mixing VIII conference, 9-12 April 2006, London
27	12th European Conference on Mixing, 27-30 June 2006, Bologna (Italia)

      The EFCE-WPM Members approved at its Meeting in 1999 held in Bradford (UK) the Booklet "Mixing: Terms, Symbols and Units" (Editor: Dr. W. Tauscher, SULZER CHEMTECH, Ltd., Winterthur, Switzerland) as an official document of the EFCE-WPM. This Booklet consists of the nomenclature of mixing technology in accordance with terminology and symbols used both in the main European Member countries of the EFCE and in the overseas countries. Recommended terms and symbols are considered as a basic nomenclature for the EFCE-WPM Events (e.g. European Conferences on Mixing) as well as for publications on research and development of mixing technology in journals of Chemical technology.

      The field of mixing covers almost the whole range of Chemical Engineering. Although, basically, mixing is a typically hydrodynamic operation it also greatly influences mass and heat transfer phenomena which frequently occur in mixed vessel and apparatuses. Therefore, it is clear that one process mechanism reflects in the final product quality and process productivity. Consequently, it is evident that the theory of such processes is rather complex. Syllabus of a Typical Mixing Course offers a possibility to teach the students at the undergraduate as well as postgraduate levels on the main features of the processes taking place in mixing technology. The EFCE-WPM discussed the needs of theoretical as well practical course on mixing and it approved in 1982 the Syllabus (Editor: Prof. J. M. Smith, University of Surrey, Great Britain).

1. Introduction, Survey of mixing vessel and reactor types
   - Process aims, end or intermediate products.
   - The reactor as part of a system, relationship to upstream and downstream processes.
   Agitated vessels, bubble columns, with and without agitators.
   loop and special reactors, choice of mixing device.
   Side entry and top entry mixers.
   Mechanical design limitations.
   In-line mixers.
    
2. Fundamentals: Shear and elongation
   - Shear stress, viscosity, non-Newtonian fluids.
   - Visco-elastic and drag reduction effects.*
   - Fluid characterisation principles of rheology.
   - Mixing by shear, striation thickness.
    
3. Hydrodynamic Concepts: Turbulence
   - Scale, intensity; spectra, constructing roll concept.
   - Distributions in mixing vessels, pseudoturbulence.*
   - Eddy sizes for dissipation, transport.
   - Kolmogoroffs theory related to energy dissipation.
   - Mixing in free turbulent Hows, jets, sheet layers, wakes.*
   - Flow field modelling, principles of k-e modelling applied to stirred tanks, limitations in heterogeneous systems.
    
4. Mixture quality and assessment
   - Scale and intensity, micromixing, macromixing; local variance.
   - Liquid phase homogeneity, macroscopic mixing time.
   - Mixing with chemical reaction, selectivity.
   - Residence time distribution.*
   - Sensors for mixing quality and microenvironment.*
   - pH, conductivity, DO and other specific probes.*
   - Mixing of high viscous and non-Newtonian media.*
   - Blending of liquids of very differing viscosities.
    
5. Macroscopic flows in stirred tank and pipe reactors
   - Demands on the impeller-suspension, circulation, micromixing, gas dispersion, mass transfer, heat transfer, etc.
   - Main geometries, impeller types.
   - Relevant dimensionless numbers. Re, Np, Fr, Fl.
   - Flow fields in STRs, baffling, ungassed and gassed power draw.
   - Pumping capacity and circulation time. Mixing time correlations.
   - Heat transfer considerations.*
   - Draught tube arrangements.*
   - Axial mixing. Laminar and turbulent diffusion in pipe flow.
   - Peclet and Bodenstein numbers. Air and reagent injection.*
   - Mixing in tees and in line jets, ejectors.*
   - Static mixers, helical (e. g. Kenics) and honeycomb (e. g. Sulzer) patterns, applications and limitations.
   - Mixing with turbulent jets in vessels, blending of liquids of differing densities.*
    
6. Impeller hydrodynamics, single phase systems
   - Details of impeller flows, vortices, structured Hows.
   - Power demand and pumping capacity, calculations.
   - Local energy dissipation.
   - Average and maximum shear rates, criteria.
   - Local pressure distribution.*
   - "Thickness of blade boundary layer.
   - Accelerating bodies, boundary layer separation, vortex shedding.*
    
7. Fluid interactions with bubbles, drops and particles
   - Bubble formation at orifices, sieve plates etc.*
   - Stresses on individual fluid particles.
   - Breakup in shear and elongating flows. Weber number.
   - Disintegration of liquid and gas jets.*
   - Local maximum time relevance in the recovery of droplets.*
   - Bubble induced flows, loop circulation.
   - Bubble forms, wakes, wake turbulence.*
   - "Turbulence modification by bubbles, particles and specific solutes.
   - Predictions of bubble or drop size distribution.
   - Three phase systems; flotation.
    
8. Principles of mass transfer in multi-phase systems*
   - General discussion of multi-step transfer processes.
   — Rate = area * driving force * mass transfer coeficient
   — i) gas-liquid; ii) liquid homogenisation; iii) liquid-particle; boundary layer/film; iv) intra particle; v) particle-liquid. Underlying assumptions of mass transfer evaluation.
    
9. Dispersion and mass transfer in Gas-Liquid Systems
   - Area creation and annihilation, dispersion.*
   - "'Bubble size distribution, the a term.
   - Impeller hydrodynamics in gas-liquid system, cavities.
   - Aerated power levels, scale-up problems.
   - Gas recirculation, hold-up, flooding, flow maps.
   - Impeller performance objectives.
   - Gas to liquid mass transfer, the k) term.
   - Predictions based on P V or on Flow maps.
   - Multi-impeller configurations, gas and power distribution.
   - Mixing of gas and liquid phases, modelling of flows within vessel.
   - "'Interpretation of mass transfer experiments in large vessels.
   - Gas dispersion with plunging jets in reactors, waste water treatment.*
   - "'Coalescence phenomena, inhibition, foaming, foam breakers.
   - "'Contaminants and additives.
   - "'Mixing problems associated with foams and froths.
   - Gas dispersion in high viscosity and non-Newtonian media.
    
10. Liquid-liquid systems
    - Dispersion of liquids in liquids.
    - Stability of emulsions, coalescence promoters.
    - Phase inversion.
    - "'Production of liquid membrane systems.
    - *Mass transfer in 1-1 systems compared with 1-g transfer.
     
11. Solid particle/flow interactions
    - Particle collisions with surfaces and other particles.*
    - Solid suspension, Zwietering criterion, basis and practice.
    - Suspension in gassed systems.
    - "'Problems with heavy or unusual particles, plates, needles.
    - "'Orientation in shear and elongating flows.
    - "'Sensitive particulate suspensions, agglomerate behaviour.
    - Flocculation processes, floe disruption.*
     
12. Liquid-particle mass transfer, coefficient determining factors*
    - Boundary layers on small bodies.*
    - "'Surface roughness effects.
    - Mass transfer between liquid and particles.*
    - Heat transfer to particles and to vessel wells.*
    - "'Precipitation processes, surface diffusion effects.
    - Mass transfer to microorganisms.*
     
13. Processing of highly viscous fluids
    - Agitator types for viscous fluid mixing: anchors, helices, ribbons.
    - Operation in the transitional Reynolds Number region.
    - Importance of whole vessel circulation.
    - Mixing in extruders, single screw ex-truder flow field and its modelling, co- and counter rotating twinscrew extruders and processors.
    - "'Selection of processor configurations.
    - Heat transfer and melting in extruders and processors.
    - "Thermal equilibration using static mixers, e. g. for spinning.
    - "'Mixing with calander rolls.
    - "'Mixing in reaction in injection moulding equipment.
     
14. Some aspects of mechanical design*
    - "'Shaft loadings, critical shaft speeds.
    - "'Variable liquid depth problems, surface interactions.
    - "'Mounting of internals, baffles.
    - "'Anti-contamination requirements, glands and bearings, sampling.
    - "'Gearboxes and speed control.
    - "'Materials of construction.
     
15. Process considerations*
    - Scale-up problems. Choice of scale-up criteria.
    - Minimum meaningful scale for experiments.
    - Design of batch reactors when viscosity changes with time.
    - When to depart from geometric similarity.*
    - "'Combination of mass transfer, diffusion and reaction kinetics.
    - "'Balance between competing demands of complex processes.
    - "'Retrofitting for increased performance.
    - "'Instrumentation for mixing control. torque.
    - "'Design and operation of fermentors and bioreactors.
     
16. Discussion of case studies
    Case studies act as a catalyst for discussion. Experience has been that such examples trigger very useful discussions in both directions. The Participants can be encouraged to use the course Tutor as a consultant who will not be charged against their own budget.