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Magnesian Cements – Fundamental for Sustainability in the Built Environment

Magnesian Cements – Fundamental for Sustainability in the Built Environment. Hobart, Tasmania, Australia where I live. I will have to race over some slides but the presentation is always downloadable from the net if you missed something. All I ask is that you think about what I am saying.

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Magnesian Cements – Fundamental for Sustainability in the Built Environment

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  1. Magnesian Cements – Fundamental for Sustainability in the Built Environment Hobart, Tasmania, Australia where I live I will have to race over some slides but the presentation is always downloadable from the net if you missed something. All I ask is that you think about what I am saying. John Harrison B.Sc. B.Ec. FCPA.

  2. Sustainability Issues

  3. The Techno – Process Our linkages to the environment are defined by the techno process

  4. Techno – Functions and Affects on the Planet → implies moving or (transport)

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

  6. The problem – Population, Technology & Affluence • The world population reached 6 billion in 1999. • Significant proportions of population increases in the developing countries have been and will be absorbed by urban areas. • Recent estimates indicate an urbanization level of 61.1% for the year 2030(1). • Affluence leads to greater consumption per capita. • Technology can have a positive or negative affect. • Impacts on the environment are by way of two major types of human activity. • The resources use • Wastage(1) UN-Habitat United Nations Human Settlements Program Global Urban Observatory Section web site at http://www.unchs.org/habrdd/global.html

  7. The Techno-Process Take → Manipulate → Make → Use → Waste [ Materials ] • What we take from the environment around us and how we manipulate and make materials out of what we take affects earth systems at both the take and waste ends of the techno-process. • The techno-process controls: • How much and what we have to take to manufacture the materials we use. • How long materials remain of utility and • What form they are in when we eventually throw them “away”.

  8. There is no such place as “Away” • The take is inefficient, well beyond what is actually used and exceeds the ability of the earth to supply. • Wastage is detrimental as there is no such place as “away” • “Away” means as waste back into the biosphere-geosphere. • Life support media within the biosphere-geosphere include water and air, both a global commons.

  9. Materials – The Key? • How and in what form materials are in when we waste them affects how they are reassimilated back into the natural flows of nature. • If materials cannot readily, naturally and without upsetting the balances within the geosphere-biosphere be reassimilated (e.g heavy metals) then they should remain within the techno-sphere and be continuously recycled as techno-inputs or permanently immobilised as natural compounds.

  10. Global Warming the Most Important? Trend of global annual surface temperature relative to 1951-1980 mean.

  11. Landfill – The Visible Legacy Landfill is the technical term for filling large holes in the ground with waste. Landfills release methane, can cause ill health in the area, lead to the contamination of land, underground water, streams and coastal waters and gives rise to various nuisances including increased traffic, noise, odours, smoke, dust, litter and pests.

  12. Our Linkages to the Environment Must be Reduced

  13. Fixing the Techno - Function We need to change the techno function to:

  14. Fixing the Techno - Function And more desirably to:

  15. Converting Waste to Resource Recycling is substantially undertaken for costly “feel good” political reasons and unfortunately not driven by sound economics Making Recycling Economic Should be a Priority

  16. The Key is To Change the Technology Paradigm • Paul Zane Pilzer’s first law states “By enabling us to make productive use of particular raw materials, technology determines what constitutes a physical resource” • Pilzer, Paul Zane, Unlimited Wealth, The Theory and Practice of Economic Alchemy, Crown Publishers Inc. New York.1990

  17. The Take • Short Use Resources • Are renewable (food) or non renewable (fossil fuels). Have short use, are generally extracted modified and consumed, may (food, air, fuels) or may not (water) change chemically but are generally altered or contaminated on return back to the geosphere-biosphere (e.g food consumed ends up as sewerage, water used is contaminated on return.)

  18. The Take – Materials = Resources • Long Term Use Resources or Materials • Materials are “the substance or substances out of which a thing is or can be made(1).” Alternatively they could be viewed as “the substance of which a thing is made or composed, component or constituent matter(2)” • Everything that lasts between the take and waste. (1) dictionary.com athttp://www.unchs.org/habrdd/global.htmlvalid as at 24/04/04 (2)The Collins Dictionary and Thesaurus in One Volume, Harper Collins, 1992

  19. Materials = Resources • Materials as Resources are Characterized as follows: • Some materials are renewable (wood), however most are not renewable unless recycled (metals, most plastics etc.) Materials generally have a longer cycle from extraction to return, remaining in the techno-sphere(1) whilst being used and before eventually being wasted. Materials may (plastics) or may not (wood) be chemically altered and are further divided into organic (e.g. wood & paper) and inorganic (e.g. metals minerals etc.) • (1) The term techno-sphere refers to our footprint on the globe, our technical world of cars, buildings, infrastructure etc.

  20. Materials - the Key to Sustainability Materials are the key to our survival on the planet. The choice of materials controls emissions, lifetime and embodied energies, maintenance of utility, recyclability and the properties of wastes returned to the geosphere-biosphere.

  21. Greatest Potential = The Built Environment • The built environment is made of materials and is our footprint on earth. • It comprises buildings • And infrastructure • It is our footprint on the planet • There are huge volumes involved. Building materials comprise • 70% of materials flows (buildings, infrastructure etc.) • 45% of waste that goes to landfill • 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. A Huge Opportunity for Sustainability

  22. 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. • 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. • That’s over 2 tonnes per person per annum TecEco Pty. Ltd. have benchmark technologies for improvement in sustainability and properties

  23. 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)

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

  25. Emissions from Cement & Lime Production • Lime and its derivatives used in construction such as Portland cement are made from carbonates. • The process of calcination involves driving off chemically bound CO2 with heat. CaCO3 →CaO + ↑CO2 ∆ • Heating requires energy. • 98% of the world’s 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).

  26. Cement Production = Carbon Dioxide Emissions

  27. Making Recycling Economic • Reducing, re-using and recycling is done more for feel good reasons than good economics and costs the community heaps! • To get over the laws of increasing returns and economies of scale and to make the sorting of wastes economic so that wastes become low cost inputs for the techno-process new technical paradigms are required. The way forward involves at least: • A new killer technology in the form of a method for sorting wastes • A killer application for unsorted wastes

  28. Intelligent Silicon in Materials? • The Cost of Silicon Chips has fallen dramatically • Silicon embedded in materials from cradle to grave would not only serve to identify cost at purchase, the first owner, movement through process, but the type of material for sorting purposes on wastage. • Robots will efficiently and productively be able to distinguish different types of plastic, glass, metals ceramics and so on.

  29. A Killer Application for Waste? • Wastes • Could be utilized depending on their class of properties rather than chemical composition? • Could be utilized in vast quantities based on broadly defined properties such as light weight, tensile strength, insulating capacity, strength or thermal capacity in composites. • Many if utilized would become net carbon sinks • TecEco binders enable wastes to be converted to resources. Two examples: • Plastics are currently hard to recycle because to be reused as inputs they cannot be mixed. Yet they would impart light weight and insulating properties to a composite bound with the new carbon dioxide absorbing TecEco eco-cements. • Sawdust and wood waste is burned in the bush contributing to global CO2. If taken to the tip, methane, which is worse is the end result. Yet wood waste it light in weight, has tensile strength, captured in a mineral binder is a carbon sink and provides excellent insulation.

  30. Recycling Materials = Reduced Emissions The above relationships hold true on a macro scale, provided we can change the technology paradigm to make the process of recycling much more efficient = economic.

  31. Technical and Biological Complexity

  32. Recycling Can Involve Remixing e.g Blending of waste streams may be required to produce input materials below toxicity levels of various heavy metals

  33. Porous Pavement – A Solution for Water Quality? Porous Pavements are a Technology Paradigm Change Worth Investigating Before three were cites forests and grassland covered most of our planet. When it rained much of the water naturally percolated though soils that performed vital functions of slowing down the rate of transport to rivers and streams, purifying the water and replenishing natural aquifers. Our legacy has been to pave this natural bio filter, redirecting the water that fell as rain as quickly as possible to the sea. Given global water shortages, problems with salinity, pollution, volume and rate of flow of runoff we need to change our practices so as to mimic the way it was for so many millions of years before we started making so many changes.

  34. EPR Legislation ? There is still room for taking responsibility for externalities with EPR Extended producer responsibility (EPR) incorporates negative externalities from product use and end-of-life in product prices Examples of EPR regulations include: Emissions and fuel economy standards (use stage) and product take back requirements (end of life) such as deposit legislation, and mandatory returns policies which tend to force design with disassembly in mind. Disposal costs are reflected in product prices so consumers can make more informed decisions. At the very least we need container legislation in this country as in S.A.

  35. Cementitious Composites of the Future • During the gestation process of concretes: • New materials have been incorporated such as fibers, fly ash and ground blast furnace slag. • These new materials have introduced improved properties. • Greater compressive and tensile strength as well as improved durability. • A generally recognised direction for the industry to achieve greater sustainability is to use more supplementary materials.

  36. Cementitious Composites of the Future • The TecEco magnesian cement technology will be pivotal in bringing about changes in the energy and emissions impacts of the built environment. • Tec-Cements Develop Significant Early Strength even with Added Supplementary Materials • Eco-cements carbonate sequestering CO2 • The CO2 released by chemical reaction from calcined materials should be captured. • TecEco kiln technology provides this capability.

  37. Cementitious Composites of the Future • Cementitious Composite like Concrete still have a long way to improve. • Diversification will result in materials more suited to specific applications required by the market. • All sorts of other materials such as industrial mineral wastes, sawdust, wood fibres, waste plastics etc. could be added for the properties they impart making the material more suitable for specific applications. (e.g. adding sawdust or bottom ash in a block formulation reduces weight and increases insulation) • More attention should also be paid to the micro engineeringand chemistry of the material.

  38. Robotics Will Result in Greater Sustainability Construction in the future will be largely done by robots. Like a colour printer different materials will be required for different parts of structures, and the wastes such as plastics can provide many of the properties required for cementitious composites of the future. A non-reactive binder such as TecEco tec-cements will be required to supply the right rheology, and like a printer, very little wasted

  39. Our Dream - TecEco Cements for Sustainable Cities

  40. The Magnesium Thermodynamic Cycle

  41. Manufacture of Portland Cement

  42. CO2 Abatement in Eco-Cements

  43. 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 product – MgO can be used to sequester more CO2 and then be re-calcined. This cycle can then be repeated.

  44. Embodied Energy and Emissions • Energy costs money and results in emissions and is the largest cost factor in the production of mineral binders. • Whether more or less energy is required for the manufacture of reactive magnesia compared to Portland cement or lime depends on the stage in the utility adding process it is measured. • Utility is greatest in the finished product which is concrete. The volume of built material is more relevant than the mass and is therefore more validly compared. On this basis the technology is far more sustainable than either the production of lime or Portland cement. • The new TecEco kiln technology will result in around 25% less energy being required and the capture of CO2 during production will result in lower costs and carbon credits. • The manufacture of reactive magnesia is a benign process that can be achieved with waste or intermittently available energy.

  45. Energy – On a Mass Basis

  46. Energy – On a Volume Basis

  47. Global Abatement

  48. Abatement from Substitution Concretes already have low lifetime energies. If embodied energies are improved could substitution mean greater market share? Figures are in millions of Tonnes

  49. Sustainability Issues Summary • We will not kick the fossil fuel habit. It will kick us when we run out of fuel. Sequestration on a massive scales is therefore essential. • To reduce our linkages with the environment we must 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.

  50. Policy Issues Summary • Research and Development Funding Priorities. • Materials should be prioritised • Procurement policies.Government in Australia is more than 1/3 of the economy and can strongly influence change through: • Life cycle purchasing policy. • Funding of public projects and housing linked to sustainability such as recycling. • Intervention Policies. • Building codes including mandatory adoption of performance specification. • Requiring the recognition and accounting for externalities • Extended producer responsibility (EPR) legislation • Mandatory use of minimum standard materials that are more sustainable • Mandatory eco-labelling • Taxation and Incentive Policies • Direct or indirect taxes, bonuses or rebates to discourage/encourage sustainable construction etc. • A national system of carbon taxes. • An international system of carbon trading ? • Sustainability Education

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