ENCYCLOPÉDIE DE LA RECHERCHE SUR L’ALUMINIUM AU QUÉBEC 2013 | Page 17

PRODUCTION DE L’ALUMINIUM
ALUMINIUM PRODUCTION

15

MODÉLISATION DE LA CONDUCTIVITÉ ÉLECTRIQUE DES MILIEUX POREUX
MODELING OF ELECTRICAL CONDUCTIVITY OF POROUS MEDIA
Geoffroy Rouget1,2, Houshang Alamdari1,2, Gholamreza Aryanpour
1

1,2,

Mario Fafard1,2, Donald Ziegler3

Department of Mining, Metallurgical and Materials Engineering, 1065 avenue de la Médecine
1
2
Université Laval, Québec, QC, G1V 0A6, Canada
2 NSERC/Alcoa Industrial Research Chair MACE3 and Aluminium Research Centre – REGAL
1 Département et Institution 1
Université Laval, Québec, QC, G1V 0A6, Canada
3 Alcoa Primary Metals, Alcoa Technical Center, 100 Technical Drive,
2 department and Institution 2.
Alcoa Center, PA 15069-0001 USA

Introduction

Auteur , Author

- The electrical behavior of the green material constituting the vibro-

compacted anodes paste before baking is not well known, a lack of studies in this field remains.
-Energy efficiency of the process is highly related to the quality, including the electrical conductivity, of the anodes.
-Electrical conductivity, in turn, could be affected by microstructural features and the intrinsic conductivity of the anode
constituents.
-The results provided by this model will help the interpretation of the data measured in situ on vibrocompacted anodes and may relate its electrical properties on its microstructure i.e anode homogeneity
and matrix distribution.
-Nielsen [1,2] proposed a model predicting the electrical conductivity of a composite material made of a
conducting matrix and a conducting filler. This model can also be used for insulating fillers. This model will
be used to describe both the behaviour of porosity in the binder matrix, and the contribution of coke
aggregates on the electrical conductivity of green anode (conducting coke and insulating pitch).

Objectives
1st Objective
Proposing a model to predict the electrical
conductivity of green carbon anodes according
to its microstructure.

2nd Objective
Identification and measurement of each of the
intrinsic parameters contained in the equation.

3rd Objective
Verification of the model comparing of the
results provided by the model with results
obtained with laboratory-made samples.

Methodology
1st

step : A mathematical model has been defined mainly based on Nielsen ‘s

model and its considerations.
2nd step : Samples will be produced following Azari’s [3] method.

Porosity contribution

3rd step : Measurement of the parameters required (K1, K2, Φm) in the model from

Binder matrix

laboratory experiments according to appropriate standards.
4th

Aggregates contribution

pores within the matrix

step : Ax factor are related to the shape of the filler. The A2 and A3 factor, need

to be estimated for both aggregates and pores. Some microstructure analyses
may be required to estimate those characteristics.
5th step : The results obtained for the binder matrix and then the whole material by
laboratory characterization will be compared to those provided by the model with
numerical simulation. A correcting factor may