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Materials – The Key to SustainabilityMaterials – The Key to Sustainability

TecEco are in the BIGGEST Business on the Planet - Solving Sustainability Problems Economically

TecEco are in the BIGGEST Business on the Planet - Solving Sustainability Problems EconomicallyThe Problem - A Planet in Crisis


A Demographic Explosion A Demographic Explosion

Developed Countries

Undeveloped Countries

Global population, consumption per capita and our footprint on the planet is exploding.

?

?


Atmospheric Carbon DioxideAtmospheric Carbon Dioxide


Global Temperature AnomalyGlobal Temperature Anomaly


The Carbon Cycle and EmissionsThe Carbon Cycle and Emissions

Source: David Schimel and Lisa Dilling, National Centre for Atmospheric Research 2003

Emissions from fossil fuels and cement production are the cause of the global warming problem


The Techno-Process & Earth SystemsThe Techno-Process & Earth Systems

Our linkages to the bio-geo-sphere 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.

Detrimental affects on earth systems

Earth Systems

Atmospheric composition, climate, land cover, marine ecosystems, pollution, coastal zones, freshwater systems, salinity and global biological diversity have all been substantially affected.

Move 500-600 billion

tonnes

Use some 50 billion

tonnes


Ecological FootprintEcological 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


Detrimental Linkages

that affect earth system

flowsTake manipulate and make impacts

End of lifecycl

e impact

s

Greater Utility Less Utility

Materials are in the Techno-sphere

Utility zoneMaterials are everything between the take and waste and affect earth system flows.

There is no such place as “away”

There are Detrimental Affects Right Through the Techno-process

There are Detrimental Affects Right Through the Techno-process


Materials Affect Underlying Molecular FlowsMaterials Affect Underlying Molecular Flows

Take → Manipulate → Make → Use → Waste [ ←Materials→ ]

[ ← Underlying molecular flow → ]

Damaging to the Environmente.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 andwhat 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.


Innovative New Materials - the Key to SustainabilityInnovative New Materials - the Key to Sustainability

Biosphere - Geosphere Techno - World

Materials are the substance of the techno-process, the link between the biosphere and techno-sphere and the key to sustainability. They are everything between and define the take and waste.

There is no such place as “away”, only a global commons

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.


Changing the Techno-processChanging the Techno-process

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

ReduceRe-useRecycle

Recycle

Reuse

Take only renewables

Waste only what is biodegradable or can be re-assimilated

Manipulate Make Use

Reduce

Materials

Take => manipulate => make => use => wasteDriven by fossil fuel energy with detrimental effects on earth systems. Eco-innovate


Materials & Lifetime & Embodied EnergiesMaterials & 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


Economically Driven SustainabilityEconomically Driven Sustainability

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.

$ - ECONOMICS - $

Sustainability will not happen by relying on people to do the right thing


Sustainability = Culture + TechnologySustainability = Culture + TechnologyIncrease in demand/price ratio for sustainability due to educationally induced cultural drift.

#

$

Demand

Supply

Increase in supply/price ratio for more sustainable products due to innovative paradigm shifts in technology.

Equilibrium shiftECONOMICS

Greater Value/for impact (Sustainability) and economic growth

Sustainability is where Culture and Technology meet. Demand Supply

New Technical Paradigms are required that deliver sustainability.


Changing the Technology ParadigmChanging 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

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


A Post – Carbon & Waste Age?A Post – Carbon & Waste Age?

Prehistoric Classic Renaissance Industrial Revolution Contemporary Post Carbon & Waste Age

Recyclable Recyclable

CO2

Wattle & daub Stone Mud brick Etc.

Stone

Stone Brick

Concrete Eco-cements

Waste

The construction industry can be uniquely responsible for helping achieve this transition

We cannot get there without new technical paradigms.


BiomimicryBiomimicry

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.


Utilizing Carbon and Wastes (Biomimicry)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


Re - Engineering MaterialsRe - Engineering Materials

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 re-

design materials to not only be more sustainable but more sustainable in use

Environmental problems are the result of inherently flawed materials, materials flows and energy systems


Materials in the Built EnvironmentMaterials 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.


Huge Potential for Sustainable MaterialsHuge Potential for Sustainable MaterialsReducing 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 aswell as chemical compositionthey become resources.

– re – engineeringmaterials toreduce the lifetimeenergy of buildings

C

C

C

C

C

Waste

Waste

Many wastes can contribute to physical properties reducing lifetime energies


Abatement and SequestrationAbatement and Sequestration To solve the greenhouse gas problem our

approach should be holistically balanced and involve– Everybody, every day– Be easy– Make money

TecEco-cements =

Low emissions production,mineral sequestration + waste utilization

Geological Seques-tration

Emissions reductionthrough efficiency andconversion to non fossil fuels

+ +

TecEco’s Contribution

New technical paradigms are required

AbatementSequestration

and


The TecEco Dream – A More Sustainable Built EnvironmentThe TecEco Dream – A More Sustainable Built Environment

MAGNESITE + OTHER INPUTS

TECECO CONCRETES

MINING

SUSTAINABLE CITIES

CO2

PERMANENT SEQUESTRATION & WASTE UTILISATION (Man made carbonate rock incorporating wastes as a building material)

CO2

MgOTECECO KILN

RECYCLED BUILDING MATERIALS

CO2

OTHERWASTES

CO2 FOR GEOLOGICAL SEQUESTRATION

We need materials that require less energy to make them, that last much longer and that contribute properties that reduce lifetime energies

“There is a way to make our city streets as green as the Amazon rainforest”. Fred Pearce, New Scientist Magazine


Impact of the Largest Material Flow - Cement and ConcreteImpact 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

TecEco Pty. Ltd. have benchmark technologies for improvement in sustainability and properties


Embodied Energy of Building MaterialsEmbodied Energy of Building Materials

Downloaded from www.dbce.csiro.au/ind-serv/brochures/embodied/embodied.htm (last accessed 07 March 2000)

Concrete is relatively environmentally friendly and has a relatively low embodied energy


Average Embodied Energy in BuildingsAverage Embodied Energy in Buildings

Downloaded from www.dbce.csiro.au/ind-serv/brochures/embodied/embodied.htm (last accessed 07 March 2000)

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.

Most of the embodied energy in the built environment is in concrete.


Emissions from Cement ProductionEmissions from Cement Production

Chemical Release– The process of calcination involves driving off chemically bound

CO2 with heat.

CaCO3 →CaO + ↑CO2

Process Energy– Most energy is derived from fossil fuels.

– 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.

CO2

CO2

CO2

CO2


Cement Production ~= Carbon Dioxide EmissionsCement Production ~= Carbon Dioxide Emissions

0

500,000,000

1,000,000,000

1,500,000,000

2,000,000,000

2,500,000,000

Metric Tonnes

Year

Between tec, eco and enviro-cements TecEco can provide a viable much more sustainable alternative.


Portland Cement & Global WarmingPortland 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


Concrete Industry ObjectivesConcrete 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 by-products such as fly ash and blast furnace slag.

WBCSD– Fuels and raw materials efficiencies– Emissions reduction during manufacture


TecEco Technologies Take Concrete into the FutureTecEco 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

– Reducing costs and take and waste impacts. Use of wastes Utilizing carbon dioxide

Magnesia component can be made using non fossil fuel energy and CO2 captured during production.

Eco-Cements

Tec -Cements

Tec & Eco-Cements


Greening the Largest Material Flow -Concrete

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– 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

Not discussed


Greening ConcreteGreening Concrete4. 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

tec-cement 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


Greening ConcreteGreening Concrete6. 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.


Waste Stream Sequestration is Part of the TecEco Total ProcessWaste Stream Sequestration is Part of the TecEco Total Process

Fe, Ni, Co.

Silicate Reactor Process e.g.

Mg2SiO4 +2CO2 =>2MgCO3 + SiO2

Silicic Acids or Silica

Solar or Wind Electricity Powered

Tec-KilnCO2 for Geological Sequestration

Oxide Reactor Process

CO2 from Power Generation, Industry or CO2 Directly From the Air

Magnesite MgCO3)

Crushing

Grinding

Screening

Magnetic Sep.

Heat Treatment

Serpentine Mg3Si2O5(OH)4

Crushing

Grinding

Screening

Gravity Concentration

Olivine Mg2SiO4

Magnesia (MgO)

MgO for TecEco Cements and Sequestration by Eco-Cements in the Built Environment

Other Wastes after Processing

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

Simplified TecEco ReactionsTec-Kiln MgCO3 → MgO + CO2 - 118 kJ/moleReactor Process MgO + CO2 → MgCO3 + 118 kJ/mole (usually more complex hydrates)

Magnesite (MgCO3)

CO2 from Power Generation or Industry

Magnesium Thermodynamic

Cycle

Waste Sulfuric Acid or Alkali?

This reaction is how most MgCO3 came to be formed anyway so why are we not using it to also sequester carbon?


TecEco Technologies Provide a Profitable SolutionTecEco Technologies Provide a Profitable Solution

Silicate → Carbonate Mineral Sequestration– 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

– 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.

TecEco

More EconomicunderKyoto?

TecEco


TecEco Kiln TechnologyTecEco Kiln Technology

CO2

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


Increasing the Proportion of Waste Materials that are Pozzolanic

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


Impact of TecEco Tec-Cement Technology on the use of Pozzolans

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


Portlandite Compared to BrucitePortlandite Compared to BruciteProperty 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


Tec-Cement Concrete Strength Gain CurveTec-Cement Concrete Strength Gain Curve

The possibility of high early strength gain with added pozzolans is of great economic and environmental importance.

Tec – Cement Concrete with 10% reactive magnesia

OPC Concrete

HYPOTHETICAL STRENGTH GAIN CURVE OVER TIME (Pozzolans added)

MPa

Log Days Plastic Stage

7 14 28 3

We have observed this kind of curve with over 300 cubic meters of concrete


Replacement of PC by Carbonating BindersReplacement 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.


Replacement of PC Carbonating BindersReplacement of PC Carbonating BindersEco-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

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

Mostly CO2 and water


Replacement with Non Carbonating BindersReplacement with Non Carbonating BindersThere 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


GeopolymersGeopolymers

“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


TecEco CementsTecEco CementsSUSTAINABILITY

DURABILITY STRENGTHTECECO CEMENTS

Hydration of the various components of Portland cement for strength.

Reaction of alkali with pozzolans (e.g. lime with fly ash.) for sustainability, durability and strength.

Hydration of magnesia => brucite for strength, workability, dimensional stability and durability. In Eco-cements carbonation of brucite => nesquehonite, lansfordite and an amorphous phase for sustainability.

PORTLAND

+ or - POZZOLAN

MAGNESIA

TecEco concretes are a system of blending reactive magnesia, Portland cement and usually a pozzolan with other materials and are a key factor for sustainability.


The Magnesium Thermodynamic CycleThe Magnesium Thermodynamic Cycle

An alkaline environment in which silicates form

Thermal decomposition MgCO3 MgO + CO2 ΔH = 118.28 kJ.mol-1 ΔG = 65.92 kJ.mol-1

Carbonation Mg(OH)2 + CO2 + 2H2O MgCO3.3 H2O ΔH = -175.59 kJ.mol-1 ΔG = -38.73 kJ.mol-1

Hydration MgO + H2O Mg(OH)2 ΔH = -81.24 kJ.mol-1 ΔG = -35.74 kJ.mol-1

Reactive phase

TOTAL CALCINING ENERGY (Relative to MgCO3) Theoretical = 1480 kJ.Kg-1 With inefficiencies = 1948 kJ.Kg-1 Nesquehonite

? Representative of other hydrated mineral carbonates including an amorphous phase and lansfordite Magnesite*

Magnesia

Dehydration

CO2

Brucite*

Eco-Cements

Tec and Enviro-Cements

CO2

CO2 CaptureNon fossil fuel energy

Calcination

We think this cycle is relatively independent of other constituents


TecEco Cement Technology Theory 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


TecEco FormulationsTecEco 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.


TecEco Cements – Impact on SustainabilityTecEco 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


Benefits to the Concrete Industry of Adopting TecEco Technology

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


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

– Reducing costs and take and waste impacts. Use of wastes Utilizing carbon dioxide

Magnesia component can be made using non fossil fuel energy and CO2 captured during production.

Eco-Cements

Tec -Cements

Tec & Eco-Cements

TecEco Technologies Take Concrete into the FutureTecEco Technologies Take Concrete into the Future


Using Aggregates that Extend CementUsing 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


Use Aggregates with Lower Embodied Energy and that Result in less Emissions

or that are Themselves Carbon Sinks

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


Improve the Performance of Concrete by Including Aggregates that

Improve or Introduce New Properties Reducing Lifetime Energies

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

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