An overview of Future Concretes An overview of the alternative mineral binder systems and composites made with them including novel concrete technologies.

An overview of Future Concretes

An overview of the alternative mineral binder systems and composites made with them including novel concrete

technologies addressing practical supply chain and economic issues including energy

10/04/23 www.tececo.comwww.propubs.com

Why Future Concretes?

• What’s wrong with the concrete we use made with Portland Cement?– Embodied energy and emissions, shrinkage, durability,

placement, tensile strength etc. etc. Not optimised for lifetime energy reduction.

• We can make better more environmentally friendly materials but what about the cost?– Better concretes don’t necessarily produce more and those

producing them will make more money.

• Concrete made for purpose = Higher Margin?– Architectural façade, insulative properties, permeable

pavement etc.

The Business Model• The industry model is like Woolworths or Coles. Head on

competition. Low margins resulting in a reliance on turnover volume and cost control to produce profits.– This model is past its use by date.

• "Firms need to embrace innovation to remain competitive. Future job creation will come as companies transform and adopt new practices. Putting it simply, firms that innovate will survive and be the market leaders of tomorrow." Source: Senator the Hon Kim Carr 24 Aug 2011

• The need to innovate under a carbon price and trading system is significantly greater than without.

• Given our problems the need to innovate goes beyond the immediate needs of the industry. There are other stakeholders

• Innovation recognises new markets

Making Money Through Innovation• In Australia rules relating to the new R & D Tax Incentive have

changed. The new scheme effective 1 July 2011 is more generous.– Make a $1 and pay 30c corporate tax– Spend a $1 to innovate thereby ensuring future profits and adding value

to your balance sheet and the government will give you either 40 or 45c as a grant.

– That’s a 70 - 75c difference!

• Given the changes the industry business model needs to change.• TecEco are also changing their business model. We are going to

register as a Research Service Provider (RSP) and become more aligned with the University of Tasmania to attract student power under my supervision.

• The leverage provided by students will increase the value of investing in R & D to well over a dollar.

What we Sell in the Industry

• Managers in the concrete industry seem to misunderstand what we sell.

• They think we sell Portland cement and concrete made with it.

• My analysis is that what we sell is the technical confidence in a liquid that sets as a solid material and it really would not matter what either was provided we could demonstrate technical merit and suitable properties.

Increases in Business Performance from the Previous Year, by Innovation Status 2008-9

Some of the Issues?

Primary Production Process Build, & Manufacture Use Dispose

Underlying Molecular FlowsPrimary

Production

Methane NOX &

SOXHeavy Metals

CO2

etc.Embodied & Process

Energy

Process,Build

&Manufacture

NOX & SOX

Heavy Metals CO2

etc.

Embodied & Process

Energy

Use

NOX & SOX

Heavy Metals CO2

etc.

Lifetime Energy

Disposeor WasteMethane

NOX & SOX

Heavy Metals

CO2

etc.

Process Energy

The Techno Process

Predicted Global Cement Demand and Emissions

Source: Quillin K. Low-CO2 Cements based on Calcium Sulfoaluminate [Internet]. Available from: http://www.soci.org/News/~/media/Files/Conference%20Downloads/Low%20Carbon%20Cements%20Nov%2010/Sulphoaluminate_Cements_Keith_Quillin_R.ashx

Energy Outlook to 2035

Source: U.S. Energy Information Administration. International Energy Outlook 2010 [Internet]. U.S. Energy Information Administration; 2010 [cited 2010 Sep 5]. Available from: www.eia.gov./oiaf/ieo/index.html

Global Waste – An Underestimate!

The challenge is to convert waste to resource.

There are Huge Change Opportunities• A wide variety of possible end uses with higher potential margins for

which current solutions are sub-optimal.– E.g. Addessing properties affecting lifetime energy.

• E.g. Mineral composites with higher “R” value– E.g. Particle boards made with mineral binders– E.g. Exterior structural panels with insulating properties

• Huge opportunities for reducing the cost base and improving the properties of concretes by focusing on the process by which they are made and what they are made with.– A few tweaks to the formulations– Major changes to the process and some– Lateral thinking in relation to aggregates.

• Every improvement counts but quantum improvements really matter – If implemented!

• Implementation issue because of the low level of skills in the industry

Our Mantra

• Think outside the square. • Spend more time thinking (R & D) less time doing

(earning low margins).• We cannot solve problems doing the same old thing

in the same old way.• The technology paradigm defines what is or is not a

resource.• Improvements through innovation = profit!• Think whole of material and whole of system• Refine definition of what’s important and what is not

Example of a Decision Matrix to Help us Improve the Future

Criterion Weight Rating Score Rating Score Rating Score Rating Score Rating Score Rating Score

Ease of Placement 10 9 90 8.5 85 3 30 7 70 0 0 7 70

Cost 8 8 64 8.5 68 9 72 7 56 0 0 7 56

Safety 7 8 56 8 56 4 28 8 56 0 0 8 56

Compressive Strength 6 8 48 7.5 45 7.5 45 6 36 6 36 6 36

Tensile Strength 5 9 45 7.5 37.5 7.5 37.5 6 30 6 30 6 30

Durability 5 9 45 7 35 7 35 8 40 8 40 8 40

Use of Pozzolanic Wastes 5 9 45 7 35 7 35 4 20 4 20 4 20

Use of Other Wastes 5 9 45 4 20 5 25 9 45 9 45 4 20

Embodied Energy 8 7 56 7 56 8 64 7 56 7 56 7 56

Embodied Emissions 8 7 56 7 56 9 72 5 40 5 40 5 40

Thermal Mass 4 8 32 8 32 8 32 7 28 7 28 7 28

Thermal Flow 4 8 32 8 32 4 16 9 36 9 36 9 36

Supply Chain 7 8 56 9 63 4 28 5 35 4 28 5 35

Total 82 107 670 97 621 83 520 88 548 65 359 83 523

Score = Rating * Weight

ALTERNATIVES

Decision ModelMg-

Carbonate MgO C4A3SMg -

Hydraulic PC Geopolymer

Rating

Score0

100

200

300

400

500

600

700

Mg - HydraulicPC

Geopolymer

DecisionModel

Scores

Alternatives

Rating

Score

Future Cement ContendersPortland Cement

1. http://www.tececo.com/files/spreadsheets/TecEcoCementLCA12Oct2011.xls

H2

O

The Potential of CO2 Release and Capture - Portland Cements

Split Process with Capture during Manufacture

No Capture during Manufacture

CO2 in atmosphere

Carbon positive. Chemical and process emissions

Net sequestration less carbon from process emissions

Use of non fossil fuels => Low or no process emissions

Clinker

Clinker

H2

O

Hydrated Cement Paste

CaCO3 + Clays CaCO3

Hydrated Cement Paste

Net Emissions (Sequestration) 0.867 kg CO2/kg product

Net Emissions (Sequestration) 0.369 Kg CO2/Kg product

CO2 capture (e.g. N-Mg process etc.)

Source Data: http://www.tececo.com/files/spreadsheets/TecEcoCementLCA12Oct2011.xls

CaO + Clays

Capture during Manufacture

Net Energy 3962 kJ/kg product

Carbon positive. Chemical and process emissions

Clinker

H2

O

Hydrated Cement Paste

CaCO3 + Clays

Net Emissions (Sequestration) 0.369 kg CO2/kg product

Net Energy 3962 kJ/kg product

Net Energy 3962 kJ/kg product

CO2 capture (e.g. N-Mg process etc.)

Future Cement ContendersMg Group

1. http://www.tececo.com/files/spreadsheets/TecEcoCementLCA12Oct2011.xls2. http://www.tececo.com/files/newsletters/Newsletter93.php

The Potential of CO2 Release and Capture Magnesium Carbonating System

MgCO3 Route using TecEco Tec-KilnWith Capture during Manufacture

No Capture during Manufacture

CO2

CO2 from atmosphere

CO2 capture (e.g. N-Mg process etc.)

Carbon neutral except for carbon from process emissions

Net sequestration less carbon from process emissions

Use of non fossil fuels => Low or no process emissions

MgO

MgO

Mg(OH)2

H2O

H2O

Mg(OH)2

H2OH2O

H2

O

MgCO3

Net Emissions (Sequestration) 0.403 Kg CO2/Kg product

Net Emissions (Sequestration) .085 kg CO2/kg product

Source Data: http://www.tececo.com/files/spreadsheets/TecEcoCementLCA14Feb2011.xls

MgCO3

H2O

Net Energy 4084 kJ/kg product

Net Energy 4084 kJ/kg product

<7250C

The Potential of CO2 Release and Capture Magnesium Carbonating System

MgCO3.3H20 Route using TecEco Tec KilnWith Capture during Manufacture

No Capture during Manufacture

CO2 CO2 from atmosphere

CO2 capture (e.g. N-Mg process etc.)

Carbon neutral except for carbon from process emissions

Net sequestration less carbon from process emissions

Use of non fossil fuels => Low or no process emissions

MgO

MgO

Mg(OH)2

H2O

H2O

Mg(OH)2

H2OH2O

H2

O

MgCO3.3H2

O

Net Emissions (Sequestration) 0.693 Kg CO2/Kg product

Net Emissions (Sequestration) - .399kg CO2/kg product

Source Data: http://www.tececo.com/files/spreadsheets/TecEcoCementLCA14Feb2011.xls

MgCO3.3H2

O

H2O

Net Energy 7140 kJ/kg product

Net Energy 7140 kJ/kg product

<4200C

Gaia Engineering

kg CO2-e/kg product1-1.0922 -.3993-1.092>2 kg CO2-e/kg Mg product

1

2

3

Or similar. The annual world production of HCl is about 20 million tons, most of which is captive (about 5 million tons on the merchant market).

The N-Mg Process

Tec-Kiln

NH3 and a small amount of CO2

MgCO3.3H2O

MgO

MgO Mg(OH)2

CO2

H2O

Steam

NH4Cl and a small amount of NH4HCO3FilterFilter

Mg rich waterAm

mon

iaca

l Mg

rich

wat

er

MgCO3.3H2O

HCl

A Modified Solvay Process for Nesquehonite

The Tec-Reactor HydroxideCarbonate Capture Cycle

• The solubility of carbon dioxide gas in seawater– Increases as the temperature approached zero and– Is at a maxima around 4oC

• This phenomenon is related to the chemical nature of CO2 and water and

• Can be utilised in a carbonate – hydroxide slurry process to capture CO2 out of the air and release it for storage or use in a controlled manner

Gaia Engineering

MgCO3.3H2

ON-Mg

Process

NH4Cl or HCl

Industrial CO2 MgOTecEcoTec-Kiln

Eco-Cements

Buildingcomponents & aggregates

TecEcoCementManufacture

CaO

Clays

Portland CementManufacture

Brine, Seawater, Oil Process water, De Sal Waste Water etc .

Tec-Cements

Other wastes

FreshWater

GBFS

Fly ash

Man Made CarbonateAggregate?

Source USGS: Cement Pages

Assumptions - 50% non PC N-Mg mix and Substitution by Mg Carbonate AggregatePercentage by Weight of Cement in Concrete 15.00%Percentage by weight of MgO in cement 6%Percentage by weight CaO in cement 29%Proportion Cement Flyash and/or GBFS 50%1 tonne Portland Cement 0.867Tonnes CO2Proportion Concrete that is Aggregate 85%CO2 captured in 1 tonne aggregate 1.092Tonnes CO2

Magnesium Carbonate Cements

• Magnesite (MgCO3) and the di, tri, and pentahydrates known as barringtonite (MgCO3·2H2O), nesquehonite (MgCO3·3H2O), and lansfordite (MgCO3·5H2O), respectively.

• Some basic forms such as artinite (MgCO3·Mg(OH)2·3H2O),hydromagnestite (4MgCO3·Mg(OH)2·4H2O) and dypingite (4MgCO3· Mg(OH)2·5H2O) also occur as minerals.

• We pointed out as early as 2001 that magnesium carbonates are ideal for sequestration as building materials mainly because a higher proportion of CO2 than with calcium can be bound and significant strength can be achieved.

• The significant strength is a result of increased density through carbonation (high molar volume increases) and the microstructure developed by some forms.

TecEco Eco-Cements

Left: Recent Eco-Cement blocks made, transported and erected in a week. Laying and Eco-Cement floor. Eco-Cement mortar & Eco-cement mud bricks. Right: Eco-Cement permeacocretes and foamed concretes

Eco-Cements are blends of one or more hydraulic cements and relatively high proportions of reactive magnesia with or without pozzolans and supplementary cementitious additions. They will only carbonate in gas permeable substrates forming strong fibrous minerals. Water vapour and CO2 must be available for carbonation to ensue.

Eco-Cements can be used in a wide range of products from foamed concretes to bricks, blocks and pavers, mortars renders, grouts and pervious concretes such as our own permeacocrete. Somewhere in the vicinity of the Pareto proportion (80%) of conventional concretes could be replaced by Eco-Cement.

TecEco Tec-Kiln, N-Mg routeThe calcination of nesquehonite has a relatively high enthalpy but there is significant scope for reducing energy using waste heat

Initial weight loss below 1000 C consists almost entirely of water (1.3 molecules per molecule of nesquehonite). Between 100 and 1500C volatilization of further water is associated with a small loss of carbon dioxide (~3-5 %).

From 1500C to 2500C, the residual water content varies between 0-6 and 0-2 molecules per molecule of MgC03. Above 3000C, loss of carbon dioxide becomes appreciable and is virtually complete by 4200C, leaving MgO with a small residual water content.

Energy could be saved using a two stage calcination process using waste energy for the first stage.

Dell, R. M. and S. W. Weller (1959). "The Thermal Decomposition of Nesquehonite MgCO3 3H20 And Magnesium Ammonium Carbonate MgCO3 (NH4)2CO3 4H2O." Trans Faraday Soc 55(10): 2203 - 2220.

Modified PC 50% Ternary Mix withN-Mg Route Mg Carbonate Aggregate

• 25-30% improvement in strength• Fast first set• Better Rheology• Less shrinkage – less cracking• Less bleeding• Long term durability• Solve autogenous shrinkage?

Criteria Good BadEnergy Requirements and Chemical Releases, Reabsorption (Sequestration?)

Use >50% replacements and still set like “normal” concrete!

Speed and Ease of Implementation Rapid adoption possible

Barriers to Deployment

Permissions and rewards systems see http://www.tececo.com/sustainability.permissions_rewards.php

Cost/Benefit Excellent until fly ash runs out!

Use of Wastes? or Allow Use of Wastes?Uses GBFS and fly ash and manufactured nesquehonite based aggregate

Performance Engineering Excellent all round Thermal High thermal capacity Architectural ExcellentSafety No issuesAudience 1Audience 2

Magnesium Phosphate Cements• Chemical cements that rely on the precipitation of insoluble magnesium

phosphate from a mix of magnesium oxide and a soluble phosphate.• Some of the oldest binders known (dung +MgO)• Potentially very green

– if the magnesium oxide used is made with no releases or via the nesquehonite (N-Mg route) and

– a way can be found to utilise waste phosphate from intensive agriculture and fisheries e.g. feedlots. (Thereby solving another environmental problem)

Criteria Good BadEnergy Requirements and Chemical Releases, Reabsorption (Sequestration?) The MgO used could be made without releases There is not much phosphate on the planetSpeed and Ease of Implementation Rapid adoption possible If barrier overcome (see below)

Barriers to Deployment

Permissions and rewards systems see http://www.tececo.com/sustainability.permissions_rewards.php. Must find a way to extract phosphate from organic pollution.

Cost/Benefit Economies of scale issue for MgO to overcome

Use of Wastes? or Allow Use of Wastes?With technology could use waste phosphate reducing water pollution

Performance Engineering Excellent all round Thermal High thermal capacity ArchitecturalSafety No issuesAudience 1Audience 2

Sorel Type Cements and DerivativesSorel Type Cements and Derivatives are all nano or mechano composites relying on a mix of ionic, co-valent and polar bonding.There are a very large number of permutations and combinations and thus a large number of patents

Criteria Good BadEnergy Requirements and Chemical Releases, Reabsorption (Sequestration?) The MgO used could be made without releasesSpeed and Ease of Implementation More could be used If barrier overcome (see below) Barriers to Deployment Not waterproof even with modification.Cost/Benefit Economies of scale issue for MgO to overcomeUse of Wastes? or Allow Use of Wastes? Not waterproofPerformance Engineering Excellent except Not waterpoof, salt affect metals Thermal High thermal capacity ArchitecturalSafety No issuesAudience 1Audience 2

Future Cement Contenders

1. http://www.tececo.com/files/spreadsheets/TecEcoCementLCA12Oct2011.xls3. Quillin, K. and P. Nixon (2006). Environmentally Friendly MgO-based cements to support sustainable construction - Final report, British Research

Establishment.

Future Cement Contenders

1. http://www.tececo.com/files/spreadsheets/TecEcoCementLCA12Oct2011.xls4. http://www.geopolymers.com.au/science/sustainability

CaO-Lime

Criteria Good BadEnergy Requirements and Chemical Releases, Reabsorption (Sequestration?) The CaO used could be made without

Speed and Ease of ImplementationEasily implemented as no carbonation rooms etc reqd.

Permissions and rewards systems see http://www.tececo.com/sustainability.permissions_rewards.php.

Barriers to Deployment We need carbon trading!Cost/BenefitUse of Wastes? or Allow Use of Wastes?Performance Engineering Good Thermal Engineered thermal capacity and conductivity. ArchitecturalSafety An irritating dustAudience 1Audience 2

Geopolymers

Criteria Good BadEnergy Requirements and Chemical Releases, Reabsorption (Sequestration?) Low provided we do not run out of fly ash

Speed and Ease of Implementation Process issues to be overcome

Permissions and rewards systems see http://www.tececo.com/sustainability.permissions_rewards.php.

Barriers to Deployment We need carbon trading!Cost/BenefitUse of Wastes? or Allow Use of Wastes?Performance Engineering Good but inconsistent Thermal Engineered thermal capacity and conductivity. ArchitecturalSafety Caustic liquorsAudience 1Audience 2

Geopolymers as a future concrete suffer from two basic flaws on one very high riskFlaw. 1. The nanoporisity flaw which leads to durability problems and Flaw. 2. The fact that water is not consumed in the geopolymerisation process resulting in the almost impossible task of making them fluid enough for placement. Too much water reduces alkalinity and hence the high risk.

Other Contenders• Slag cements a variant of Portland cement as CSH is the main product.• Supersulfated cements have potential as they are made mostly from GBFS

and gypsum which are wastes and only a small amount of PC or lime. The main hydration product is ettringite and they show good resistance to aggressive agents including sulphate but are slow to set. (A derivative)

• Calcium aluminate cements are hydraulic cements made from limestone and bauxite. The main components are monocalcium aluminate CaAl2O4 (CA) and mayenite Ca12Al14O33 (C12A7) which hydrate to give strength. Calcium aluminate cements are chemically resistant and stable to quite high temperatures.

• Calcium sulfoaluminate cements & belite calcium sulfoaluminate cements are low energy cements that have the potential to be made from industrial by products such as low calcium fly ash and sulphur rich wastes. The main hydration product producing strength is ettringite. Their use has been pioneered in China (A derivative)

Other Contenders• Belite cements can be made at a lower temperature and contains less lime

than Portland cement and therefore has much lower embodied energy and emissions. Cements containing predominantly belite are slower to set but otherwise have satisfactory properties. Many early Portland type cements such as Rosendale cement were rich in belite like phases. (a variant, See http://www.tececo.com/links.cement_rosendale.php.)

• PC - MgO – GBFS – fly ash blends. MgO is the most powerful new tool in hydraulic cement blends since the revelation that reactive magnesia can be blended with other hydraulic cements such as Portland cement. 25-30% improvements in compressive strength and greater improvements in tensile strength, faster first set, better rheology and less shrinkage and cracking less bleeding and long term durability have been demonstrated. It is also possible autogenous shrinkage has been solved.

• MgO blended with other hydraulic cements, pozzolans and supplementary cementitious materials (SCM’s). Amazingly very little real research has been done on optimised blends particularly with cements other than Portland cement.