ENCYCLOPÉDIE DE LA RECHERCHE SUR L’ALUMINIUM AU QUÉBEC 2013 | Page 42

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NOUVEAUX PRODUITS ET MATÉRIAUX À BASE D'ALUMINIUM
NEW ALUMINIUM BASED PRODUCTS AND MATERIALS
RÉCUPÉRATION DE LA CHALEUR RÉSIDUELLE
RECYCLING OF WASTE HEAT

Nasim Razavinia, Prof. Frank Mucciardi, Prof. Ferri Hassani
Mining and Material Engineering, McGill University

Energy Recovery System
Background

Scope

Aluminum production is estimated to
exceed 120 Mt by 2025. The average
energy required by a smelter is 15
kWh/kg of aluminum . About 20 to
50% of the energy consumed is lost
through hot exhaust fluids (30-45%),
heat transfer from hot walls and from
heated product streams (≈ 35%).
Capturing and converting a fraction of
the waste heat will result in an
increase in the overall efficiency of the
process.

Combine heat pipe technology with a heat engine to
create an innovative heat and power cycle.
1) Developing heat pipe technology to the point that it
can capture and concentrate low grade waste heat.
2) Developing an engine that can convert low grade
energy to electricity.
3) Coupling the heat pipe and engine to create the
Heat Pipe-Engine combination that can take waste
heat and transform it into electricity

Schematic of The Heat Pipe-Engine
Cycle

The configuration has a hot heat pipe feeding energy
to the engine and a cold heat pipe unit removing the
unconverted energy from the engine.

Energy Extraction System
CFD Modeling

Experiments

Nasim Razavinia
Frank Mucciardi
Ferri Hassani
Département de
génie des mines
et des matériaux,
Université McGill

Energy Conversion System
Heat Pipe Engine - Prototype

Experiments

Engine’s Parameters
Cylinder Area (m2)

0.0081

Approximate Max Pressure (atm)

2

Approximate Minimum Pressure (atm)

0.5

Max Pressure in the cylinder (atm)

1.95

Pressure at Top Dead Center(m3 (atm)

1

Volume at Top Dead Center(m3)

0.24174

Volume at Bottom Dead Center (m3)

0.000773

3

0.240967

Swept Volume (m )

Calculations

Journée des étudiants – REGAL

Conclusions
• A heat pipe regardless of its size can
have heat flux of 14 kW/m2 from waste
heat flow at 250⁰C.
• Minimum theoretical power for 150 rpm
is estimated to be 90 kWatt per unit
area [m2] of the piston.
• The power of the current setting of the
engine is estimated to be 50 Watts.

It is estimated that by 2025, global aluminum consumption will increase to
On estime que d'ici 2025, la consommation mondiale d'aluminium augmentera
QC, Canada, 22 translates
à 120 Mt/yr. Cela se traduit par une croissance dans laPalais des congrès de Montréal,120 Mt/yr. This octobre 2013to a growth in the world’s production of about 800 Mt
production mondiale
of bauxite and alumina combined. The result is the generation of significant
d'environ 800 Mt de bauxite et alumine combinés. Le résultat est la génération de
quantities of waste heat. Thus, technological enhancements such as increasing
quantités énormes de chaleur perdue. Donc, des améliorations technologiques
the efficiency of aluminum smelters, reducing the use of fossil fuels and use of
comme une augmentation de l'efficacité des fonderies d'aluminium, une réduction
other fuel sources are all essential.At McGill a new approach to harness waste
de l'utilisation des combustibles fossiles et un changement vers d’autres sources
heat that is a by-product of aluminium production is proposed. This new process
d'énergie sont essentielles. À l'Université McGill, une nouvelle approche pour
will both increase the overall efficiency of aluminium production and reduce the
récupérer de la chaleur résiduelle qui est un sous-produit de la production
use of fossil fuel. This is achieved by introducing an innovative CHP, termed the
d'aluminium est proposée. Ce nouveau processus augmentera l'efficacité globale
“heat pipe cycle”. This cycle consists of heat pipes that are coupled with pistonde la production d'aluminium et ainsi réduira l'utilisation de combustibles fossiles.
cylinder configuration heat engine. Our study shows the possibility of achieving a
Ceci est obtenu en introduisant une technologie innovante CHP, appelée le
10% increase in the efficiency of the process.
« cycle de caloducs ». Ce cycle est fait de caloducs et il est couplé avec un moteur
thermique à configuration piston-cylindre. Notre étude montre la possibilité de
réaliser une augmentation de 10% dans l'efficacité du processus.