Transcript Slide 1

Materials – The Key to Sustainability
The Problem - A Planet in Crisis
TecEco are in
the BIGGEST
Business on the
Planet Solving
Sustainability
Problems
Economically
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1
A Demographic Explosion
?
?
Undeveloped
Countries
Developed
Countries
Global population, consumption per capita and our
footprint on the planet is exploding.
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2
Atmospheric Carbon Dioxide
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3
Global Temperature Anomaly
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4
The Carbon Cycle and Emissions
Emissions
from fossil
fuels and
cement
production
are the
cause of the
global
warming
problem
Source: David Schimel and Lisa Dilling, National Centre for Atmospheric Research 2003
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5
The Techno-Process & Earth Systems
Our linkages to
the bio-geosphere are
defined by the
techno process
describing and
controlling the
flow of matter
and energy. It
is these flows
that have
detrimental
linkages to
earth systems.
Earth Systems
Detrimental
affects on
earth
systems
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Atmospheric
composition,
climate, land
cover, marine
ecosystems,
pollution,
coastal zones,
freshwater
systems,
salinity and
global
biological
diversity have
all been
substantially
affected.
6
Ecological Footprint
Our footprint is exceeding the capacity of the
planet to support it. We are not longer sustainable
as a species and must change our ways
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There are Detrimental Affects Right
Through the Techno-process
Detrimental
Linkages that
affect earth
system flows
Take
manipulate
and make
impacts
Materials are
End of
in the
lifecycle
Technoimpacts
sphere Utility
zone
Materials are everything between the take
There
is no
such
place
as
“away”
and waste and affect earth system flows.
Greater Utility
Less Utility
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Materials Affect Underlying Molecular Flows
Take → Manipulate → Make → Use → Waste
[
[
←Materials→
]
← Underlying molecular flow → ]
Damaging to the Environment
e.g. heavy metals, cfc’s, c=halogen
compounds and CO2
Materials influence:
How much and what we have to take to manufacture the materials we use.
How long materials remain of utility, whether they are easily recycled and how
and
what form they are in when we eventually throw them “away”.
What we take from the environment around us, how we manipulate and make
materials out of what we take and what we waste result in underlying molecular
flows that affect earth systems.
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Innovative New Materials - the Key to Sustainability
The choice of materials controls emissions, lifetime and embodied
energies, user comfort, use of recycled wastes, durability, recyclability
and the properties of wastes returned to the bio-geo-sphere.
There is no such place as “away”, only a global commons
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Changing the Techno-process
Take => manipulate => make => use => waste
Driven by fossil fuel energy with detrimental effects on earth systems.
Reduce
Re-use
Recycle
Reduce
Take only
renewables
Manipulate
Make
Eco-innovate
Reuse
Use
Waste only what is
biodegradable or can
be re-assimilated
Recycle
Materials
Improving the sustainability of materials used to create the built environment
will reduce the impact of the take and waste phases of the techno-process
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11
Materials & Lifetime & Embodied Energies
 The embodied energy of materials only contributes 1-2% of
the total energy consumed by buildings over their lifetime
 It follows that the properties of materials such as specific
heat and conductance are more important to the overall
energy consumption and thus emissions
 New materials and materials composites can introduce
physical properties that result in them being more
sustainable in use
 In many instances wastes will provide the physical properties
required
 Currently unheard of paradigms such as materials with high
specific heat and low conductance will increase the
performance of buildings
 An opportunity will emerge to introduce such composites
with the introduction of robotics
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Economically Driven Sustainability
$ - ECONOMICS - $
The challenge is to harness human
behaviours which underlay economic
supply and demand phenomena by
changing the technical paradigm in
favour of making carbon dioxide and
other wastes resources for new
materials with lower take and waste
impacts and more energy efficient
performance.
Sustainable processes are more efficient and therefore more
economic. Natural ecosystems can be 100% efficient. What is needed
are new technologies that allow material and energy flows to more
closely mimic natural ecosystems.
Innovation will deliver these new technical paradigms.
Sustainability will not happen by relying
on people to do the right thing
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Sustainability = Culture + Technology
Increase in demand/price ratio for
sustainability due to educationally
induced cultural drift.
$
ECONOMICS
New Technical
Paradigms are
required that deliver
sustainability.
Equilibrium shift
Supply
Greater Value/for
impact
(Sustainability) and
economic growth
Increase in supply/price ratio for
more sustainable products due to
innovative paradigm shifts in
technology.
Demand
#
Sustainability is where Culture and Technology meet.
Demand
Supply
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Changing the Technology Paradigm
We need materials that require less energy to
make them, that last much longer and that
contribute properties that reduce lifetime energies.
The key is to change the technology paradigm
“By enabling us to make productive use of
particular raw materials, technology
determines what constitutes a physical
resource1”
1.Pilzer, Paul Zane, Unlimited Wealth, The Theory and Practice of
Economic Alchemy, Crown Publishers Inc. New York.1990
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A Post – Carbon & Waste Age?
The construction
industry can be
uniquely responsible
for helping achieve this
transition
We cannot get there
without new technical
paradigms.
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Biomimicry
 The term biomimicry was popularised by the book of
the same name written by Janine Benyus
 Biomimicry is a method of solving problems that uses
natural processes and systems as a source of
knowledge and inspiration.
 It involves nature as model, measure and mentor.
The theory behind biomimicry is that natural processes
and systems have evolved over several billion years
through a process of research and development
commonly referred to as evolution. A reoccurring theme
in natural systems is the cyclical flow of matter in such a
way that there is no waste of matter or energy.
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Utilizing Carbon and Wastes (Biomimicry)
 During earth's geological history large tonnages of
carbon were put away as limestone and other
carbonates and as coal and petroleum by the activity of
plants and animals.
 Sequestering carbon in magnesium binders and
aggregates in the built environment mimics nature in that
carbon is used in the homes or skeletal structures of
most plants and animals.
We all use carbon and wastes to
make our homes! “Biomimicry”
In eco-cement blocks
and mortars the
binder is carbonate
and the aggregates
are preferably wastes
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Re - Engineering Materials
Environmental
problems are
the result of
inherently
flawed
materials,
materials flows
and energy
systems
 To solve environmental problems
we need to understand more
about materials in relation to the
environment.
– the way their precursors are derived and
their degradation products re assimilated
• and how we can reduce the impact of
these processes
– what energies drive the evolution,
devolution and flow of materials
• and how we can reduce these energies
– how materials impact on lifetime energies
 With the knowledge gained redesign materials to not only be
more sustainable but more
sustainable in use
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Materials in the Built Environment
 The built environment is made of materials and is
our footprint on earth.
– It comprises buildings and infrastructure.
 Building materials comprise
– 70% of materials flows (buildings, infrastructure etc.)
– 40-50% of waste that goes to landfill (15 % of new materials
going to site are wasted.)
 At 1.5% of world GDP Annual Australian production of
building materials likely to be in the order 300 million
tonnes or over 15 tonnes per person.
 Over 20 billion tonnes of building materials are used
annually on a world wide basis.
– Mostly using virgin natural resources
– Combined in such a manner they cannot easily be separated.
– Include many toxic elements.
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Huge Potential for Sustainable Materials
Reducing the impact of the take and
waste phases of the techno-process.
– including carbon in materials
they are potentially carbon sinks.
– including wastes for
physical properties as
well as chemical composition
C
they become resources.
– re – engineering
Waste
materials to
reduce the lifetime
energy of buildings C
Many wastes can
contribute to
physical
properties
reducing lifetime
energies
C
C
Waste
C
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Abatement and Sequestration
 To solve the greenhouse gas problem our
approach should be holistically balanced and
involve
– Everybody, every day New technical
Sequestration
paradigms are
– Be easy
Abatement
required
– Make money
and
+
+
Emissions reduction
through efficiency and
conversion to non fossil
fuels
TecEco-cements =
Low emissions production,
mineral sequestration
+ waste utilization
Geological
Sequestration
TecEco’s Contribution
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The TecEco Dream – A More Sustainable Built Environment
CO2
CO2 FOR
GEOLOGICAL
SEQUESTRATION
CO2
MINING
MAGNESITE
+ OTHER
INPUTS
“There is a way to
make our city streets
as green as the
Amazon rainforest”.
Fred Pearce, New
Scientist Magazine
TECECO
KILN
MgO
OTHER
WASTES
PERMANENT
SEQUESTRATION &
WASTE
UTILISATION (Man
made carbonate
rock incorporating
wastes as a
TECECO CONCRETES building material)
RECYCLED
BUILDING
MATERIALS
SUSTAINABLE CITIES
We need materials that
require less energy to
make them, that last
much longer and that
contribute properties
that reduce lifetime
energies
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Impact of the Largest Material Flow - Cement and Concrete
 Concrete made with cement is the most widely
used material on Earth accounting for some
30% of all materials flows on the planet and 70%
of all materials flows in the built environment.
– Global Portland cement production is currently in the
order of 2 billion tonnes per annum.
– Globally over 14 billion tonnes of concrete are poured
per year.
– Over 2 tonnes per person per annum
– Much more concrete is used than any other building
material.
TecEco Pty. Ltd. have benchmark technologies for
improvement in sustainability and properties
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Embodied Energy of Building Materials
Concrete is
relatively
environmentally
friendly and has a
relatively low
embodied energy
Downloaded from www.dbce.csiro.au/indserv/brochures/embodied/embodied.htm (last accessed 07 March 2000)
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Average Embodied Energy in Buildings
Most of the embodied energy in the
built environment is in concrete.
Because so much concrete is used there is a
huge opportunity for sustainability by reducing
the embodied energy, reducing the carbon
debt (net emissions) and improving properties
that reduce lifetime energies.
Downloaded from www.dbce.csiro.au/indserv/brochures/embodied/embodied.htm (last accessed 07 March 2000)
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Emissions from Cement Production
 Chemical Release
– The process of calcination involves driving off chemically bound
CO2 with heat.
CaCO3 →CaO + ↑CO2
CO2
 Process Energy
– Most energy is derived from fossil fuels.
CO2
– Fuel oil, coal and natural gas are directly or indirectly burned to
produce the energy required releasing CO2.
 The production of cement for concretes accounts for around
10% of global anthropogenic CO2.
– Pearce, F., "The Concrete Jungle Overheats", New Scientist, 19 July,
No 2097, 1997 (page 14).
Arguments that we should reduce cement production relative to other
building materials are nonsense because concrete is the most sustainable
building material there is. The challenge is to make it more sustainable.
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Cement Production ~= Carbon Dioxide Emissions
Metric Tonnes
2,500,000,000
2,000,000,000
1,500,000,000
1,000,000,000
500,000,000
2001
1996
1991
1986
1981
1976
1971
1966
1961
1956
1951
1946
1941
1936
1931
1926
0
Year
Between tec, eco and enviro-cements TecEco can provide a
viable much more sustainable alternative.
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Portland Cement & Global Warming
 Concrete is the third largest contributor to CO2 emissions
after the energy and transportation sectors.
 The cement industry is growing at around 5% a year
globally. Mainly China, Thialand and India.
 On current trends world production of Portland cement
will reach 3.5 billion tonnes by 2020 - a three fold
increase on 1990 levels.
 To achieve Kyoto targets the industry will have to emit
less than 1/3 of current emissions per tonne of concrete.
 Carbon taxes and other legislative changes will provide
legislative incentive to change.
 There is already strong evidence of market incentive to
change
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Concrete Industry Objectives
PCA (USA)
– Improved energy efficiency of fuels and raw
materials
– Formulation improvements that:
• Reduce the energy of production and minimize
the use of natural resources.
• Use of crushed limestone and industrial byproducts such as fly ash and blast furnace slag.
WBCSD
– Fuels and raw materials efficiencies
– Emissions reduction during manufacture
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TecEco Technologies Take Concrete into the Future
 More rapid strength gain even with added
pozzolans
– More supplementary materials can be used reducing
costs and take and waste impacts.
 Higher strength/binder ratio
 Less cement can be used reducing costs and
take and waste impacts
 More durable concretes
Tec Cements
– Reducing costs and take and waste impacts.
 Use of wastes
 Utilizing carbon dioxide
Tec & EcoEco-Cements Cements
 Magnesia component can be made using non
fossil fuel energy and CO2 captured during
production.
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Greening the Largest Material Flow Concrete
1. Scale down Production.
– Untenable nonsense, especially to developing
nations
2. Use waste for fuels
– Not my area of expertise but questioned by many.
3. Reduce net emissions from manufacture
Not
discussed
– Increase manufacturing efficiency
– Increase fuel efficiency
– Waste stream sequestration using MgO and CaO
•
E.g. Carbonating the Portlandite in waste concrete
– Given the current price of carbon in Europe this could be
viable
•
TecEco have a mineral sequestration process that is
non fossil fuel driven using MgO and the TecEco kiln
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Greening Concrete
4. Increase the proportion of waste materials that are
pozzolanic
– Using waste pozzolanic materials such as fly ash and slags has
the advantage of not only extending cement reducing the
embodied energy and net emissions but also of utilizing waste.
•
•
•
•
We could run out of fly ash as coal is phasing out. (e.g. Canada)
TecEco technology will allow the use of marginal pozzolans
Slow rate of strength development can be increased using TecEco teccement technology.
Potential long term (50 year plus) durability issues overcome using
tec-cement technology.
5. Replace Portland cement with viable alternatives
– There are a number of products with similar properties to Portland
cement
•
•
Carbonating Binders
Non-carbonating binders
– The research and development of these binders needs to be
accelerated
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Greening Concrete
6. Use aggregates that extend cement
–
Use air as an aggregate making cement go further
•
•
•
Aluminium use questionable
Foamed Concretes work well with TecEco eco-cement
Use for slabs to improve insulation
7. Use aggregates with lower embodied energy and that
result in less emissions or are themselves carbon sinks
–
Other materials that be used to make concrete have lower embodied
energies.
•
•
•
–
Local aggregates
Recycled aggregates from building rubble
Glass cullet
Materials that non fossil carbon are carbon sinks in concrete
•
Plastics, wood etc.
8. Improve the performance of concrete by including
aggregates that improve or introduce new properties reducing
lifetime energies
–
Wood fibre reduces weight and conductance.
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Waste Stream Sequestration is Part of the TecEco Total Process
Olivine
Mg2SiO4
Serpentine
Mg3Si2O5(OH)4
Crushing
Crushing
Grinding
CO2 from Power
Generation or Industry
Grinding
Waste Sulfuric
Acid or Alkali?
Screening
Screening
Silicate Reactor Process e.g.
Magnetic Sep.
Fe,
Ni,
Co.
Mg2SiO4 +2CO2 =>2MgCO3 + SiO2
Gravity Concentration
Heat Treatment
Silicic Acids or Silica
Magnesite (MgCO3)
Simplified TecEco Reactions
Tec-Kiln MgCO3 → MgO + CO2 - 118 kJ/mole
Reactor Process MgO + CO2 → MgCO3 + 118 kJ/mole (usually
more complex hydrates)
Solar or Wind Electricity
Powered Tec-Kiln
CO2 for Geological
Sequestration
Magnesia (MgO)
Other Wastes
after
Processing
Magnesium
Thermodynamic Cycle
Magnesite MgCO3)
Oxide Reactor
Process
MgO for TecEco Cements and
Sequestration by Eco-Cements in the Built
Environment
This reaction
is how most
MgCO3 came
to be formed
anyway so
why are we
not using it to
also
sequester
carbon?
CO2 from Power Generation, Industry
or CO2 Directly From the Air
Tonnes CO2 Sequestered per Tonne Silicate with Various Cycles
through the TecEco Process (assuming no leakage MgO to built
environment i.e complete cycles)
Chrysotile
(Serpentinite)
Billion Tonnes
Forsterite (Mg
Olivine) Billion
Tonnes
Tonnes CO2 sequestered by 1 billion tonnes of mineral mined directly
.4769
.6255
Tonnes CO2 captured during calcining
.4769
.6255
Tonnes CO2 captured by eco-cement
.4769
.6255
Total tonnes CO2 sequestered or abated per tonne mineral mined
(Single calcination cycle).
1.431
1.876
Total tonnes CO2 sequestered or abated (Five calcination cycles.)
3.339
4.378
Total tonnes CO2 sequestered or abated (Ten calcination cycles).
5.723
7.506
Total tonnes CO2 sequestered or abated (Twenty calcination cycles).
11.446
15.012
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TecEco Technologies Provide a Profitable Solution
 Silicate → Carbonate Mineral Sequestration
TecEco
– Using either peridotite, forsterite or serpentine as
inputs to a silicate reactor process CO2 is sequestered
and magnesite produced.
– Proven by others (NETL,MIT,TNO, Finnish govt. etc.)
 Tec-Kiln Technology
– Combined calcining and grinding in a closed system
allowing the capture of CO2. Powered by waste heat,
solar or solar derived energy.
– To be proved but simple and should work!
 Direct Scrubbing of CO2 using MgO
TecEco
More
Economic
under
Kyoto?
– Being proven by others (NETL,MIT,TNO, Finnish govt.
etc.)
 Tec and Eco-Cement Concretes in the Built
Environment.
– TecEco eco-cements set by absorbing CO2 and are as
good as proven.
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TecEco Kiln Technology





 Can run at low temperatures.
 Can be powered by variable non fossil fuel
energy.
 Runs 25% to 30% more efficiency.
 Theoretically capable of producing much
more reactive MgO
– Even with ores of high Fe content.
Captures CO2 for bottling and sale to the oil industry
(geological sequestration).
Grinds and calcines at the same time.
Part of a major process to solve global CO2 problems.
Will result in new markets for ultra reactive low lattice
energy MgO (e.g. cement, paper and environment
industries)
TecEco need your backing to develop the kiln
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Increasing the Proportion of Waste
Materials that are Pozzolanic
 Advantages
– Lower costs
– More durable greener concrete
 Disadvantages
– Rate of strength development retarded
– Potential long term durability issue due to leaching of Ca from
CSH.
• Glasser and others have observed leaching of Ca from CSH and this will
eventually cause long term unpredictable behavior of CSH.
• Resolved by presence of brucite in tec-cements
– Higher water demand due to fineness.
– Finishing is not as easy
 Supported by WBCSD and virtually all industry
associations
 Driven by legislation and sentiment
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Impact of TecEco Tec-Cement
Technology on the use of Pozzolans
 In TecEco tec-cements Portlandite is
generally consumed by the pozzolanic
reaction and replaced with brucite
– Increase in rate of strength development particularly
in the first 3-4 days.
• Internal consumption of water by MgO as it hydrates
reducing impact of fineness demand
• More pozzolanic reactions
• Mg Al hydrates?
– Improved durability as brucite is much less soluble or
reactive
• Potential long term durability issue due to leaching of
Ca from CSH resolved.
– Improved finishing as Mg++ contributes a strong
shear thinning property
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Portlandite Compared to Brucite
Property
Portlandite (Lime)
Brucite
Density
2.23
2.9
Hardness
2.5 – 3
2.5 – 3
Solubility (cold)
1.85 g L-1 in H2O at 0 oC
0.009 g L-1 in H2O at 18
oC.
Solubility (hot)
.77 g L-1 in H2O at 100 oC .004 g L-1 H2O at 100 oC
Solubility (moles, cold)
0.000154321 M L-1
0.024969632 M L-1
Solubility (moles, hot)
0.000685871 M L-1
0.010392766 M L-1
Solubility Product (Ksp)
5.5 X 10-6
1.8 X 10-11
Reactivity
High
Low
Form
Massive, sometime
fibrous
Usually fibrous
Free Energy of
Formation of
Carbonate Gof
- 64.62 kJ.mol-1
-19.55 kJ.mol-1
-119.55 kJ.mol-1(via
hydrate)
Cement chemists in the industry should be
getting their heads around the differences
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Tec-Cement Concrete Strength Gain Curve
HYPOTHETICAL STRENGTH
GAIN CURVE OVER TIME
(Pozzolans added)
MPa
We have
observed
this kind of
curve with
over 300
cubic
meters of
concrete
Tec – Cement Concrete with
10% reactive magnesia
OPC Concrete
3
Plastic
Stage
7
14
28
Log Days
The possibility of high early strength gain
with added pozzolans is of great economic
and environmental importance.
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Replacement of PC by Carbonating Binders
Lime
– The most used material next to Portland cement in
binders.
– Generally used on a 1:3 paste basis since Roman
times
– Non-hydraulic limes set by carbonation and are
therefore close to carbon neutral once set.
CaO + H2O => Ca(OH)2
Ca(OH)2 + CO2 => CaCO3
33.22 + gas ↔ 36.93 molar volumes
– Very slight expansion, but shrinkage from loss of
water.
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Replacement of PC Carbonating Binders
 Eco-Cement (TecEco)
– Have high proportions of reactive magnesium oxide
– Carbonate like lime
– Generally used in a 1:5-1:12 paste basis because much more
carbonate “binder” is produced than with lime
MgO + H2O <=> Mg(OH)2
Mostly CO2
and water
Mg(OH)2 + CO2 + H2O <=> MgCO3.3H2O
58.31 + 44.01 <=> 138.32 molar mass (at least!)
24.29 + gas <=> 74.77 molar volumes (at least!)
– 307 % expansion (less water volume reduction) producing much
more binder per mole of MgO than lime (around 8 times)
– Carbonates tend to be fibrous adding significant micro structural
strength compared to lime
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43
Replacement with Non Carbonating Binders
There are a number of other novel cements
with intrinsically lower energy requirements
and CO2 emissions than conventional
Portland cements that have been developed
– High belite cements
• Being research by Aberdeen and other universities
– Calcium sulfoaluminate cements
• Used by the Chinese for some time
– Magnesium phosphate cements
• Proponents argue that a lot stronger than Portland
cement therefore much less is required.
• Main disadvantage is that phosphate is a limited
resource
– Geopolymers
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Geopolymers
 “Geopolymers” consists of SiO4 and AlO4 tetrahedra linked
alternately by sharing all the oxygens.
– Positive ions (Na+, K+, Li+, Ca++, Ba++, NH4+, H3O+) must be present
in the framework cavities to balance the negative charge of Al3+ in
IV fold coordination.
 Theoretically very sustainable
 Unlikely to be used for pre-mix concrete or waste in the
near future because of.
– process problems
• Requiring a degree of skill for implementation
– nano porosity
• Causing problems with aggregates in aggressive environments
– no pH control strategy for heavy metals in waste streams
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TecEco Cements
SUSTAINABILITY
PORTLAND
+ or - POZZOLAN
Hydration of the
various components
of Portland cement
for strength.
DURABILITY
Reaction of alkali with
pozzolans (e.g. lime with fly
ash.) for sustainability,
durability and strength.
TECECO CEMENTS
STRENGTH
TecEco concretes are
a system of blending
MAGNESIA
reactive magnesia,
Hydration of magnesia => brucite for strength, workability, Portland cement and
dimensional stability and durability. In Eco-cements
usually a pozzolan
carbonation of brucite => nesquehonite, lansfordite and an with other materials
amorphous phase for sustainability.
and are a key factor
for sustainability.
Presentation downloadable from www.tececo.com
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The Magnesium Thermodynamic Cycle
Calcination
CO2 Capture
Non fossil fuel energy
We think this cycle is relatively
independent of other constituents
Presentation downloadable from www.tececo.com
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TecEco Cement Technology Theory
Portlandite (Ca(OH)2) is too soluble, mobile
and reactive.
– It carbonates, reacts with Cl- and SO4- and being
soluble can act as an electrolyte.
TecEco generally (but not always) remove
Portlandite using the pozzolanic reaction
and
TecEco add reactive magnesia
– which hydrates, consuming water and
concentrating alkalis forming brucite which is
another alkali, but much less soluble, mobile or
reactive than Portlandite.
In Eco-cements brucite carbonates
Presentation downloadable from www.tececo.com
48
TecEco Formulations
 Tec-cements (Low MgO)
– contain more Portland cement than reactive magnesia. Reactive magnesia
hydrates in the same rate order as Portland cement forming Brucite which uses
up water reducing the voids:paste ratio, increasing density and possibly raising
the short term pH.
– Reactions with pozzolans are more affective. After all the Portlandite has been
consumed Brucite controls the long term pH which is lower and due to it’s low
solubility, mobility and reactivity results in greater durability.
– Other benefits include improvements in density, strength and rheology, reduced
permeability and shrinkage and the use of a wider range of aggregates many of
which are potentially wastes without reaction problems.
 Eco-cements (High MgO)
– contain more reactive magnesia than in tec-cements. Brucite in porous
materials carbonates forming stronger fibrous mineral carbonates and therefore
presenting huge opportunities for waste utilisation and sequestration.
 Enviro-cements (High MgO)
– contain similar ratios of MgO and OPC to eco-cements but in non porous
concretes brucite does not carbonate readily.
– Higher proportions of magnesia are most suited to toxic and hazardous waste
immobilisation and when durability is required. Strength is not developed
quickly nor to the same extent.
Presentation downloadable from www.tececo.com
49
TecEco Cements – Impact on Sustainability
 The CO2 released by calcined carbonates used to make
binders can be captured using TecEco kiln technology.
 Tec-Cements Develop Significant Early Strength even with
Added Supplementary Materials.
– Around 15 - 30% less total binder is required for the same strength.
 Eco-cements carbonate sequestering CO2 requiring 25-75%
less binder in some mixes
 Both tec and eco=cements provide a benign low pH
environment for hosting large quantities of waste overcoming
problems of:
– Using acids to etch plastics so they bond with concretes.
– sulphates from plasterboard etc. ending up in recycled construction
materials.
– heavy metals and other contaminants.
– delayed reactivity e.g. ASR with glass cullet
– Resolving durability issues
Presentation downloadable from www.tececo.com
50
Benefits to the Concrete Industry of
Adopting TecEco Technology
 Utilizing wastes to make concretes.
– Tec-cements have more rapid strength development with fly
ash, bottom ash, industrial slags etc. (Tec-Cements.)
 Reducing energy and emissions during the
production of cements.
– MgO can be made using non fossil fuel energy
 Concretes containing MgO
– are demonstrably more durable.
– can incorporate wastes that contribute to physical
properties reducing lifetime energies
 It makes sense to sequester carbon by allowing
MgO to re-carbonate and thereby gain strength.
The biggest business on the planet is going
to be the sustainability business
Presentation downloadable from www.tececo.com
51
TecEco Technologies Take Concrete into the Future
 More rapid strength gain even with added
pozzolans
– More supplementary materials can be used reducing
costs and take and waste impacts.
 Higher strength/binder ratio
 Less cement can be used reducing costs and
take and waste impacts
 More durable concretes
Tec Cements
– Reducing costs and take and waste impacts.
 Use of wastes
 Utilizing carbon dioxide
Tec & EcoEco-Cements Cements
 Magnesia component can be made using non
fossil fuel energy and CO2 captured during
production.
Presentation downloadable from www.tececo.com
52
Using Aggregates that Extend Cement
 Air used in foamed concrete is a cheap low embodied
energy aggregate and has the advantage of reducing
the conductance of concrete.
– Concrete, depending on aggregates weighs in the order of
2350 Kg/m3
– Concretes of over 10 mp as light as 1000 Kg/m3 can be
achieved.
– At 1500 Kg/m3 25 mpa easily achieved.
 From our experiments so far with Buildlite Cellular
Concrete PL tec-cement formulations increase
strength performance by around 5-10% for the same
mass.
 Claimed use of aluminium and autoclaving to make
more sustainable blocks questionable
Presentation downloadable from www.tececo.com
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Use Aggregates with Lower Embodied
Energy and that Result in less Emissions
or that are Themselves Carbon Sinks
 Use of aggregates that lower embodied energies
– wastes such as recycled building rubble tec and eco-cements do
not have problems associated with high gypsum content
 Use of other aggregates that include non fossil carbon
– sawdust and other carbon based aggregates can make eco-cement
concretes a net carbon sink.
 Reduce transport embodied energies by using local materials
such as earth
– mud bricks and adobe.
– our research in the UK and with mud bricks in Australia indicate that
eco-cement formulations seem to work much better than PC for this
Presentation downloadable from www.tececo.com
54
Improve the Performance of Concrete
by Including Aggregates that
Improve or Introduce New Properties
Reducing Lifetime Energies
 Rather than be taken to landfill many wastes can
be used to improve properties of concrete that
reduce lifetime energies.
– For example paper and plastic have in common
reasonable tensile strength, low mass and low
conductance and can be used to make cementitious
composites that assume these properties
Presentation downloadable from www.tececo.com
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