11

Presentation of some researches Covered by the Working Group 2

Jean-Claude ROUX

Laboratory of Pulp and Paper Science and Graphic Arts, CNRSGrenoble Institute of Technology – Pagora

461 rue de la Papeterie, 38 400 Saint-Martin d’Hères, France

jean-claude.roux@grenoble-inp.fr

COST FP 1005 – Fiber suspension flow modelling: a key for innovation and competitiveness in the pulp and paper industry

13-14 October 2011 - Nancy

22

Outline

Presentation of our Laboratory of Pulp and Paper Science and

Graphic Arts

Some researches covered by WG1 (Martine RUEFF)

Some researches in the fields covered by WG2

33

Presentation of our Laboratory

Laboratory of Pulp and Paper Science and Graphic Arts = LGP2

composed of 5 research teams:

*Chemical Processes – Biorefinery – Pulping –Bleaching – Bioproducts

*Papermaking Engineering and Environment

*Paper Physics

*Printing and Graphic Arts

*Biomaterials for Packaging

35 Ph-D students – 10 Ph-D thesis are defended each year

44

Some researches covered by WG2

How can we use some rheological concepts for understanding the complex behaviour of flowing pulp suspensions in the unit operations of papermaking science?

- Consider a single-phase Eulerian modelling > shear rate, pulp apparent viscosity : what is the meaning of this last tool simultaneously in terms of :

*reduction of the energy consumption for a given operation?

*optimization of pulp and paper properties?

- Application to disintegration and refining operations of pulp suspensions will be given

55

Some researches covered by WG2

Disintegration operation (2 Ph-D thesis among 2 on the theme)

FABRY (1999) : «Rheology of concentrated pulp suspensions in order to improve their recycling »

AMARAL (2001): « Disintegration of pulp : characterization and quantification of the effects »

Refining operation (2 Ph-D thesis among 5 on the theme)

RADOSLAVOVA (1996): «Hydrodynamic modelling of the refining process of pulp suspensions »

BORDIN (2008): «Study of the modification of the rheological behaviour of pulp suspensions during the refining operation »

6

Disintegration process: special case of pulp deinking

FABRY(1999)

*New objectives: waste paper defibreing, ink detachment without fragmentation, speck decontamination

*An extension of the METZNER & OTTO’s method (1957) provides an interesting tool to integrate the overall friction phenomena:

- generalisation of the apparent viscosity to a shear-factor studied in a Hobart planetary mixer

- furnish: 100% ONP (Old NewsPrint)

7

Disintegration process FABRY(1999): master curve with water-glycerol mixtures

Flat beater Hook impeller

factorimpeller,d.N.

fd.N.

P 2

53n

8

Disintegration process FABRY(1999): analysis of the overall friction in the mixer

The shear-factor function of the consistency and the impeller geometry

9

Disintegration process FABRY(1999): master curve for defibreing in a planetary mixer

Net cumulative energy consumed

10

Disintegration process FABRY(1999): master curve for ink fragmentation in a planetary mixer

Net cumulative energy consumed

11

Pulp disintegration process: physical description

and generalization given by AMARAL et al.(2000)

- The process kinetic follows a law of evolution which includes an average shearing stress in the bulk

- The Rayleigh’s law can be applied and all the friction forces may be incorporated in a “viscous form” called a shear-factor

dt.FF.ktdF

x.exp....k 50.0sw0

0 and are 2 numerical constants to be determined

12

Application to the experimental data already published

MERRETT(1987), SAVOLAINEN(1991), AMARAL et al.(2000)

k calc. = 0.984 k eval.

0.000

0.004

0.008

0.012

0.016

0.000 0.004 0.008 0.012 0.016

k evaluated from direct measurements (s-1)

k ca

lcul

ated

val

ues

(s-1

)

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Application to the experimental data already published

MERRETT(1987), SAVOLAINEN(1991), AMARAL et al.(2000)

Authors Fibrous raw material0

1sPa

.

01 /

sPa .

Eucalyptus pulp 310017 ., 143 67Amaral etal.

Softwood pine pulp 210088 ., 412. 105

Mixed of wastepapers

410165

., 1940 765.Merrett

Wet strength boards 510316 ., 15900 926.

Box corrugatedpapers

410741 ., 5740 957.Savolainenet al.

Calendered papers 310492 ., 403 262.

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Publications in journals

On the operation of pulp disintegration:AMARAL, M.E., RENAUD, M., ROUX, J.C.,

« Cinétique de désintégration des pâtes à papier : modélisation du phénomène »

Revue A.T.I.P., 54, (3-4), pp 76-84, juillet-septembre 2000

FABRY, B., ROUX, J.C., CARRE, B.,

« Characterization of friction during pulping : an interesting tool to achieve good deinking »

Journal of Pulp and Paper Science, 27, (8), pp 284-288, août 2001

ROUX, J.C., FRANC, N., DUFFY, F.F., FABRY, B.,

« Shear factor : a new way to characterize fiber suspension shear »

TAPPI Journal, 84, (8), août 2001

FABRY, B., ROUX, J.C., CARRE, B., DUFFY, F.F.,

« Shear factor : a new way to characterize pulper performance »

TAPPI Journal-Peer Reviewed Paper Solutions, 84, (11), novembre 2001

ROUX, J.C.,

“Review paper on pulp treatment processes”

The Pulp and Paper Fundamentals Research Soc., FRC Editor, Oxford, pp 19-80, sept. 2001

VILASECA F., PUIG J., PELACH M.A., El-MANSOURI N.E., ALCALA M., ROUX J.-C., MUTJE P.,

Study and modelling of the disintegration kinetics of coated paper

BioResources 6 (2), 1659-1669, 2011

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Presentation of the project on the refining operation

J.-C. Roux, J.-F. Bloch, G. Besançon

Title: Energetic optimization of the running of refiners in the paper industry

Statement: for the refining operation, in 2009, the French electricity consumption for all paper companies climbs until : 200 kWh/T . 8 330 000 T/an

= 1,67.109 kWh/an

5% of the reduction of the electricity consumption for the refining operation represents 8,33 107 kWh/an, or 8,33 M€/an

Understand for a better control the refining operation

in terms of a multivariate non linear process

2011

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Motor Refiner Sensors + Model for the

Controller electrical disc Acquisition C total P

Calculated net P

Model of the no-load P e N

-

+

Pnet

SP

+

-

Calculated total P

Exemple of a control scheme for the refiner running with a constant set point (SP) for the net power

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International context and difficulties(1) influence of variables : raw materials

(2) influence of geometric parameters and running conditions

(3) Model of knowledge

Country

Place

Canada

UBC Vancouver

Poland

Lodz

Portugal

UBI

Covilha

Sweden

KTH, STFI

Stockholm

Finland

Aalto

Helsinki

France

INP-LGP2

Grenoble

Level studied for the refining

operation

1, 2, 3 1, 2 1, 2 1 1, 2 1, 2, 3

Semi-industrial refining pilot

Yes Yes No Yes Yes Yes

Difficulties : Sensors (real or virtual)

Optimal control / energetic criteria

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Publications in journals only -1

Our expertise on the refining operation understanding:ROUX, J.C., CHU, J., JORIS, G., CAUCAL, G.,

« Théorie hydro-mécanique du fonctionnement d’un raffineur à basse concentration »

Revue A.T.I.P., 53, (4-5), pp 106-116, septembre-octobre 1999

ROUX, J.C., MAYADE, T.,

« Modeling of the particle breakage kinetics in the wet mills for the paper industry »

Powder Technology, 105, (1-3), pp 237-242, novembre 1999

ROUX, J.C., JORIS, G.,

« Specific Edge Load: advantages and drawbacks »

Japanese Journal of Paper Technology, 46, (10), pp 55-59, octobre 2003

ROUX, J.C., JORIS, G.,

« Angular parameters beyond specific edge load »

TAPPSA Journal, Technical Asso. Pulp and Paper Industry South Africa, mai 2005

ROUX, J.C., JORIS, G.,

« Radial distribution of the pressure in an industrial refiner »

13rd Fundamentals Research Symposium : Advances in Paper Science and Technology, 1, pp 409-425

PIRA Editions, 2005

DIETEMANN, P., ROUX, J.C.,

« A study of disc refiner running in no-load conditions »

Cellulose Chemistry and Technology, 39, (5-6), pp 459-471, 2005

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Publications in journals only - 2

On the refining operation:ROUX, J.C., BLOCH, J.F., NORTIER, P.,

“A kinetic model for pulp refining, including the angular parameters of the equipment”,

Appita Journal, 60, (1), pp 29-34, January 2007

BORDIN, R., ROUX, J.C., BLOCH, J.F.,

“Global description of refiner plate wear in low consistency beating”,

Nordic Pulp and Paper Research Journal, 22, n°4-2007, pp 529-534

BORDIN, R., ROUX, J.C., BLOCH, J.F.,

“New technique for measuring clearance in low-consistency refiners”,

Appita Journal, 61, (1), pp 71-77, January 2008

BORDIN, R., ROUX, J.C., BLOCH, J.F.,

“No-load power evolution during low-consistency pulp beating”,

Nordic Pulp and Paper Research Journal, 23, n°1-2008, pp 34-38

ROUX, J.C., BLOCH J.-F., R. BORDIN and P. NORTIER

« The net normal force per crossing point: a unified concept for the low consistency refining of pulp suspensions »

14th Fundamental Research Symposium : Advances in Pulp and Paper Research, 1, pp 51-83

Cambrian Printers, 2009

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Proposed scheme of research for this project

Phase 1 – (4 months)

Bibliographical work: at the interface between the paper engineering and the process control

Phase 2- (8 months)

Development of the experimental pilot (specific sensors) (LGP2)

Phase 3- (8 months)

Development of a first attempt of optimal control (GIPSA Lab)

Phase 4 – (6 months)

Valorisation (conferences and articles in journals)

Phase 5 – (10 months)

Extension to other types of refiners (depending on the advancement of the project)