Raw Material challenges in refractory application
Dr. Erwan Guéguen
Dipl.- Geol. Johannes Hartenstein
Dr. Cord Fricke-Begemann
Magnesita Refractories SCS - France
Magnesita Refractories Gmbh - Germany
Fraunhofer Institute for Laser Technology ILT - Germany
Refractory Industry Overview
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Refractory Classification
By Application:

Unshaped Products also called Monolithics
versus Shaped Products (namely bricks).
By Type of bonding for Shaped products:


Ceramic bonded bricks (carbon free) = Fired bricks
Carbon bonded bricks = Tempered bricks
By Chemical behaviour which depends upon the main raw
material:
There are acid, neutral and basic Products.

Basis for this is the reaction with Water:
Example
 Oxide + Water = Acid
Silica
 Oxide + Water = no Reaction
Alumina
 Oxide + Water = Basic
Magnesia
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Refractory Raw Material
 The most important Raw Materials for Refractories are:
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Refractory Raw Material
 Pure Materials have a defined Melting Point.
 The Melting Point of a Mixture is always below the Melting Point of the Pure
Components.
 Eutectic point.
Fireclay Brick (45%
Al2O3)
Lowering of
Melting
Point
≈ 1200°C !!
Reaction Slag
Dolomite Brick (58%
CaO)
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Refractory properties versus Raw Material
Thermal Properties like
• Thermal Expansion,
• Heat Capacity,
• Thermal Conductivity,
• Refractoriness (Refractoriness under Load – Creep in Compression),
Are determined by the Refractory Raw Material
Physical Properties like
• Raw Density – Porosity – Permeability,
• Crushing Strength – Modulus of Rupture,
• Elasticity,
• Thermal Shock Resistance,
Are mainly determined by the Raw Material and Production Process.
Wear Resistance or Corrosion Resistance do not depend on the Raw
Materials only or the Production Process. They are influenced significantly by
the Conditions in Use. (Steel Grades – Slag Type - Temperatures, Kiln Type Local Atmosphere,...)
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Refractory Product conception
Oxides
C containing
bricks
Resin, Pitch,
Oil,...
Fired Bricks
Temporary
Binder,
Phosphate,
Clay,...
Antioxydant for
instance
Al/ Si/
Al-Mg/ B4C
CaB6
Binders
Refractory
Additives
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MgO, Doloma,
Alumina,...or
combination
Carbon
Sources
Micropowders,
.....
Graphite
Carbon Black
Refarctory microstructure
Typical microstructure of Mag-C bricks
Binder
Magnesia
Binder
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Graphite
Magnesia
Important Refractory Raw Materials
Source: PRE
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Raw Material price trends (2007-2013)
Significant price increase for:
- Bauxite
- Graphite
- Sintered Magnesia
- Fused Magnesia
Source: PRE
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Critical Raw Materials for EU
List of Critical Raw Materials edited by EU in 2014 : 54 Materials reviewed from which
20 are considered as being critical
EU commission Statement: « It’s worth recalling that all Raw Materials, even when not
critical, are important for the European Economy, and therefore not being critical doesn’t
imply that a given Raw Material and its availability to the European economy should be
neglected »
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Raw Material Challenge for Refractory
Refractory suppliers are under significant
pressure with respect to...
… how to still improve in the customers
the value in use of products
The industry is highly exposed to
international competition
Invest and increase the use of
own raw materials and strictly
control of the costs
Raw materials represents 40-50% of the
cost of refractories
Develop use of externally
sourced recycled refractory
materials
Raw materials play a fundamental role
on product quality
China is currently the main supplier of
high volume of important Refractory
grade raw materials
Development of supply chain
for obtaining used refractory
materials that can be
successfully processed and used
for refractory brick production
Besides
Raw material cost, energy cost and
environmental regulation
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REFRASORT Project
European Commision
7th Framework Programme for Research, Technological development and Demonstration
Funding of new Research projects for shaping a more ressource efficient economy in Europe
REFRASORT Project
« Innovative Technologies for High Grade Recycling Refractory waste using non
destructive technology »
Objective = To develop an automated sorting and separation technology for used
Refractory material without comminution which provides pure high quality secondary
raw materials adapted to the needs of Refractory production
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LIBS technology
Key technology to enable automated separation = identification of individual pieces of
Refractories
Direct Laser analysis promises to fulfil the sensor
requirements for industrial operation in a separation plant
Sensor-based Sorting System using
Laser Direct Analysis for Material
Identification
Laser-induced Plasma on a Piece of
used Refractory
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LIBS technology
Ability of LIBS to distinguish main types of Refractories
MgO
Doloma
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Al-Si
THANK YOU FOR YOUR ATTENTION
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