Greening the Heartland

1. Greening the Heartland Earthship Brighton (UK) – The first building utilising TecEco eco-cements I will have to race over some slides but the presentation is always downloadable from the TecEco web site if you missed something. John Harrison B.Sc. B.Ec. FCPA.

2. The Problem – A Planet in Crisis TecEco are in the BIGGEST Business on the Planet - Solving Sustainability Problems Economically

3. A Demographic Explosion ? Undeveloped Countries Developed Countries Global population, consumption per capita and our footprint on the planet is exploding.

4. Atmospheric Carbon Dioxide

5. Global Temperature Anomaly

6. The Techno-Process Global Systems Atmospheric composition, climate, land cover, marine ecosystems, pollution, coastal zones, freshwater systems, salinity and global biological diversity have all been substantially affected. 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

7. 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

8. Illinois Before Settlement

9. Illinois Now Paper Mill - Soda liquor + Cl Farming - Pesticide, N & K Habitat removal Vehicles - carbon dioxide Cows - methane Cities Immediate and polluted water run-off.Air pollution.Carbon dioxide and other gases.Other wastes. Huge linkages. Huge impacts

10. Illinois with a Little Lateral Thinking & Effort Less paper. Other Cl free processes - no salinity Cows – CSIRO anti methane bred Organic farming. Carbon returned to soils. Use of zeolite reduces water and fertilizer required by 2/3 TecEco technology provides ways ofsequestering carbon dioxide and utilizing wastes to create our techno - world Evolution away from using trees – paperless office Vehicles – more efficient and using fuel cells Sequestration processes Cities: Porous pavement prevents immediate and polluted run-off. Carbon dioxide and other gases absorbed by TecEco eco-cements. Less wastes. Carbon based wastes converted to energy or mulches and returned to soils. Buildings generate own energy etc. Less impacts

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

12. Embodied Energy of Building Materials Concrete is relatively environmentally friendly and has a relatively low embodied energy Downloaded from www.dbce.csiro.au/ind-serv/brochures/embodied/embodied.htm (last accessed 07 March 2000)

13. Average Embodied Energy in Buildings Most of the embodied energy in the built environment is in concrete. But because so much is used there is a huge opportunity for sustainability by reducing the embodied energy, reducing the carbon debt (net emissions) and improving properties. Downloaded from www.dbce.csiro.au/ind-serv/brochures/embodied/embodied.htm (last accessed 07 March 2000)

14. Emissions 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%(1) of global anthropogenic CO2. (1) Pearce, F., "The Concrete Jungle Overheats", New Scientist, 19 July, No 2097, 1997 (page 14).

15. Cement Production = Carbon Dioxide Emissions

16. Sustainability • Sustainability is a direction not a destination. • Our approach should be holistically balanced and involve • Everybody, every process, every day. + + Mineral SequestrationEco-cements in cities + Waste utilization Emissions reductionthrough efficiency andconversion to non fossil fuels Geological Seques-tration

17. Converting Waste to Resource Recycle Waste only what is biodegradable or can be re-assimilated Take only renewables → Manipulate → Make→ Use → ReuseRe-make [ ←Materials→ ] [← Underlying molecular flows →] Materials control: 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. Problems in the global commons today include heavy metals, halogen carbon double bond compounds, CFC’s too much CO2 etc.

18. Innovative New Materials - the Key to Sustainability The choice of materials in construction 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

19. Sustainability Through Materials Innovation • Problems in the global commons today can only be changed by changing the molecular flows underlying planetary anthropogenic materials flows in the techno-process so that the every day behaviors of people interacting in an economic system will deliver new more sustainable flows. • This will not happen because it is the right thing to do. Pilzer's first law states that the technology paradigm defines resources. Changing the flow of materials therefore has to be economic. WBCSD President Björn Stigson 26 November 2004“Technology is a key part of the solutions for sustainable development. Innovation and technology are tools for achieving higher resource efficiency in society.”

20. Sustainability = Culture + Technology Increase in demand/price ratio for sustainability due to educationally induced cultural drift. $ Supply Greater Value/for impact (Sustainability) and economic growth Equilibrium shift ECONOMICS Demand Increase in supply/price ratio for more sustainable products due to innovative paradigm shifts in technology. # Sustainability is where Culture and Technology meet. Demand Supply

21. Huge Potential for Sustainable Materials in the Built Environment C C Waste C Waste C C • 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.) • 40-45% of waste that goes to landfill (15 % of new materials going to site are wasted.) • Reducing the impact of the take and waste phases of the techno-process. • By including carbon in materialsthey are potentially carbon sinks. • By including wastes forphysical properties aswell as chemical compositionthey become resources

22. Innovative New Materials Vital • It is possible to achieve Kyoto targets as the UK are proving, but we need to go way beyond the treaty according to our chief scientists. • Carbon rationing has been proposed as the only viable means to keep the carbon dioxide concentration in the atmosphere below 450 ppm. • Atmospheric carbon reduction is essential, but difficult to politically achieve by rationing. • Making the built environment not only a repository for recyclable resources (referred to as waste) but a huge carbon sink is an alternative and adjunct that is politically viable as it potentially results in economic benefits. • Concrete, a cementitous composite, is the single biggest material flow on the planet with over 2.2 tonnes per person produced. • Eco-cements offer tremendous potential for capture and sequestration using cementitious composites. MgCO3 → MgO + ↓CO2 - Efficient low temperature calcination & captureMgO + ↓CO2 + H2O → MgCO3.3H2O - Sequestration as building material∆

23. Sustainability Summary • A more holistic approach is to reduce energy consumption as well as sequester carbon. • To reduce our linkages with the environment we must convert waste to resource (recycle). • Sequestration and recycling have to be economic processes or they have no hope of success. • We cannot stop progress, but we can change and historically economies thrive on change. • What can be changed is the technical paradigm. CO2 and wastes need to be redefined as resources. • New and better materials are required that utilize wastes including CO2 to create a wide range of materials suitable for use in our built environment.

24. TecEco Technology More information at www.tececo.com

25. The TecEco Total Process Serpentine Mg3Si2O5(OH)4 Olivine Mg2SiO4 Crushing Crushing Grinding CO2 from Power Generation or Industry Grinding Waste Sulfuric Acid or Alkali? Screening Screening Magnetic Sep. Silicate Reactor Process Iron Ore. Gravity Concentration Heat Treatment Silicic Acids or Silica Magnesite (MgCO3) Simplified TecEco ReactionsTec-Kiln MgCO3 → MgO + CO2 - 118 kJ/moleReactor Process MgO + CO2 → MgCO3 + 118 kJ/mole (usually more complex hydrates) Solar or Wind Electricity Powered Tec-Kiln CO2 for Geological Sequestration Magnesium Thermodynamic Cycle Magnesite MgCO3) Magnesia (MgO) Other Wastes after Processing Oxide Reactor Process CO2 from Power Generation, Industry or CO2 Directly From the Air MgO for TecEco Cements and Sequestration by Eco-Cements in the Built Environment

26. Why Magnesium Compounds • At 2.09% of the crust magnesium is the 8th most abundant element. • Magnesium oxide is easy to make using non fossil fuel energy and efficiently absorbs CO2 • Because magnesium has a low molecular weight, proportionally a much greater amount of CO2 is released or captured. • A high proportion of water means that a little binder goes a long way. In terms of binder produced for starting material in cement, eco-cements are nearly six times more efficient.

27. TecEco Technologies • 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 EconomicunderKyoto? TecEco

28. TecEco Kiln Technology • Grinds and calcines at the same time. • Runs 25% to 30% more efficiency. • Can be powered by solar energy or waste heat. • Brings mineral sequestration and geological sequestration together • Captures CO2 for bottling and sale to the oil industry (geological sequestration). • The products – CaO &/or MgO can be used to sequester more CO2 and then be re-calcined. This cycle can then be repeated. • Suitable for making reactive reactive MgO.

29. A Post – Carbon Age We all use carbon and wastes to make our homes! “Biomimicry”

30. Drivers for TecEco Technology Government Influence Carbon Taxes Provision of Research Funds Environmental education TecEco kiln technology could be the first non fossil fuel powered industrial process Consumer Pull Environmental sentimentCost and technical advantages?Competition? Huge Markets Cement 2 billion tonnes. Bricks 130,000 million tonnes Producer Push The opportunity cost of compliant waste disposal Profitability and cost recovery Technical merit Resource issues Robotics Research objectives TecEco cements are the only binders capable of utilizing very large quantities of wastes based on physical property rather than chemical composition overcoming significant global disposal problems, and reducing the impact of landfill taxes. TecEco eco-cements can sequester CO2 on a large scale and will therefore provide carbon accounting advantages.

31. Drivers for Change – Robotics • Using Robots to print buildings is all quite simple from a software, computer hardware and mechanical engineering point of view. • The problem is in developing new construction materials with the right flow characteristics so they can be squeezed out like toothpaste, yet retain their shape until hardened • Once new materials suitable for the way robots work have been developed economics will drive the acceptance of robots for construction • Concretes for example will need to evolve from being just a high strength grey material, to a smorgasbord of composites that can be squeezed out of a variety of nozzles for use by a robotic workforce for the varying requirements of a structure • TecEco cement concretes have the potential of achieving the right shear thinning characteristics required

32. TecEco Cements More information at www.tececo.com More slides on web site

33. TecEco Cements SUSTAINABILITY PORTLAND + or - POZZOLAN 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. TECECO CEMENTS DURABILITY STRENGTH MAGNESIA 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. 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.

34. The Magnesium Thermodynamic Cycle

35. TecEco Cement Sustainability • TecEco technology will be pivotal in bringing about sustainability in the built environment. • 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 25 = 30% less total binder is required for the same strength. • Eco-cements carbonate sequestering CO2 • 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 • Durability issues

36. 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.

37. TecEco Cement Technology • 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 forming brucite which is another alkali, but much less soluble, mobile or reactive than Portlandite. • In Eco-cements brucite carbonates The consequences of need to be considered.

38. Why Add Reactive Magnesia? • To maintain the long term stability of CSH. • Maintains alkalinity preventing the reduction in Ca/Si ratio. • To remove water. • Reactive magnesia consumes water as it hydrates to possibly hydrated forms of brucite. • To reduce shrinkage. • The consequences of putting brucite through the matrix of a concrete in the first place need to be considered. • To make concretes more durable • Because significant quantities of carbonates are produced in porous substrates which are affective binders. Reactive MgO is a new tool to be understood with profound affects on most properties

39. What is Reactive MgO? or Lattice Energy Destroys a Myth • Magnesia, provided it is reactive rather than “dead burned” (or high density, crystalline periclase type), can be beneficially added to cements in excess of the amount of 5 mass% generally considered as the maximum allowable by standards prevalent in concrete dogma. • Reactive magnesia is essentially amorphous magnesia with low lattice energy. • It is produced at low temperatures and finely ground, and • will completely hydrate in the same time order as the minerals contained in most hydraulic cements. • Dead burned magnesia and lime have high lattice energies • Crystalline magnesium oxide or periclase has a calculated lattice energy of 3795 Kj mol-1 which must be overcome for it to go into solution or for reaction to occur. • Dead burned magnesia is much less expansive than dead burned lime (Ramachandran V. S., Concrete Science, Heydon & Son Ltd. 1981, p 358-360 )

40. Summary of Reactions Involved We think the reactions are relatively independent. Notice the low solubility of brucite compared to Portlandite and that nesquehonite adopts a more ideal habit than calcite & aragonite

41. Strength with Blend & Porosity Tec-cement concretes Eco-cement concretes High Porosity Enviro-cement concretes High Magnesia High OPC STRENGTH ON ARBITARY SCALE 1-100

42. Tec-Cement Concrete Strength Gain Curve • Concretes are more often than not made to strength. • The use of tec-cement results in • 20-30% greater strength or less binder for the same strength. • more rapid early strength development even with added pozzolans. • Straight line strength development for a long time strength gain with less cement and added pozzolans is of great economic and environmental importance.

43. Reasons for Strength Development in Tec-Cements. • Reactive magnesia requires considerable water to hydrate resulting in: • Denser, less permeable concrete. • A significantly lower voids/paste ratio. • Higher early pH initiating more effective silicification reactions? • The Ca(OH)2 normally lost in bleed water is used internally for reaction with pozzolans. • Super saturation of alkalis caused by the removal of water? • Micro-structural strength due to particle packing (Magnesia particles at 4-5 micron are a little over ½ the size of cement grains.) • Slow release of water from hydrated Mg(OH)2.nH2O supplying H2O for more complete hydration of C2S and C3S? • Formation of MgAl hydrates? Similar to flash set in concrete but slower??

44. Water Reduction During the Plastic Phase Water is required to plasticise concrete for placement, however once placed, the less water over the amount required for hydration the better. Magnesia consumes water as it hydrates producing solid material. Less water results in less shrinkage and cracking and improved strength and durability. Concentration of alkalis and increased density result in greater strength.

45. Tec-Cement Compressive Strength Graphs by Oxford Uni Student

46. Tec-Cement Tensile Strength Graphs by Oxford Uni Student Tensile strength is thought to be caused by change in surface charge on MgO particles from +ve to –ve at Ph 12 and electrostatic attractive forces

47. Other Strength Testing to Date • BRE (United Kingdom) • 2.85PC/0.15MgO/3pfa(1 part) : 3 parts sand - Compressive strength of 69MPa at 90 days. • Note that there was as much pfa as Portland cement plus magnesia. Strength development was consistently greater than the OPC control • TecEco Large Cement Company Modified 20 MPa mix

48. Increased Density – Reduced Permeability • Concretes have a high percentage (around 18% - 25%) of voids. • On hydration magnesia expands 116.9 % filling voids and surrounding hydrating cement grains and compensates for the shrinkage of Portland cement. • Brucite is 44.65 mass% water. • Lower voids:paste ratios than water:binder ratios result in little or no bleed water less permeability and greater density. • Compare the affect to that of vacuum dewatering.

49. Reduced Permeability • As bleed water exits ordinary Portland cement concretes it creates an interconnected pore structure that remains in concrete allowing the entry of aggressive agents such as SO4--, Cl- and CO2 • TecEco tec - cement concretes are a closed system. They do not bleed as excess water is consumed by the hydration of magnesia. • Consequences: • Tec - cement concretes tend to dry from within, are denser and less permeable and therefore stronger more durable and more waterproof. Cement powder is not lost near the surfaces. • Tec-cements have a higher salt resistance and less corrosion of steel etc.

50. Tec-Cement pH Curves