Presentation on theme: "Gaia Engineering for Planetary Engineers"— Presentation transcript:
1 Gaia Engineering for Planetary Engineers John Harrison Presentation AASMIC ConferenceGaia Engineering for Planetary Engineers?Global population, consumption per capita and our footprint on the planet are exploding.A Planet in Crisis?Undeveloped CountriesDemographic Explosion =>Developed CountriesDEMOGRAPHICSGlobal population, consumption per capita and our footprint on the planet is exploding.The graph shows population. I wouldn’t like to see a graph of per capita consumption added. The two together would be frightening.The world population passed 6 billion in At the current rate the world will have 7 billion people soon after the year The overwhelming share of world population growth is taking place in developing countries and has more than doubled in 35 years, growing from 1.89 billion in 1955 to 4.13 billion in 1990.Significant proportions of population increases in the developing countries have been and will be absorbed by urban areas which are growing five times faster than urban areas in developed countries.This presentation describes a recyclable world made of composites of carbon and other wastes. A world in which and our entourage of rats mice and cockroaches can live, make money and thrive.John Harrison B.Sc. B.Ec. FCPA. FAICD Managing director of TecEco and Chair of AASMIC
2 Our Ecological Footprint Exceeds Capacity John Harrison Presentation AASMIC ConferenceOur Ecological Footprint Exceeds CapacitySource: WWF State of the Planet, 2005Our footprint is exceeding the capacity of the planet to support it. We are not longer sustainable and the environment is no longer sustainable – we must change our ways to survive.View further to discover how
3 John Harrison Presentation AASMIC Conference EnergyPeak Oil Production (Campell 2004)Most models of oil reserves, production and consumption show peak oil around 2010 (Campbell 2005) and serious undersupply and rapidly escalating prices by It follows that there will be economic mayhem unless the we act now to reduce and change the energy base of our economies.
4 The Carbon Cycle and Emissions John Harrison Presentation AASMIC ConferenceThe Carbon Cycle and EmissionsEmissions from fossil fuels and cement production are a significant cause of global warming.We need to increase the sedimentary carbon sinkCEMENT EMMISSIONSCement manufacture contributes significantly to global warming as I am sure Vijay Rangan has or will tell you. As members of the industry we are trying to do something about the problem. That is why we are all here today4.5 billion years of geological sequestration have resulted in 7% of the crust being carbonateUnits: GtC GtC/yrAfter: David Schimel and Lisa Dilling, National Centre for Atmospheric Research 2003
5 John Harrison Presentation AASMIC Conference Global WarmingRises in the levels of greenhouse gasesATMOSPHERIC CARBON DIOXIDEOf particular concern and therefore the most studied is the problem of CO2 in the atmosphere and the global warming that results. The level of CO2 from the burning of fossil fuels is rising too rapidly for natural processes to absorb and in the air has risen from 280 parts per million in pre-industrial times to just under 380 parts per million in 2004.Are causing a rapid rise in temperature
6 CO2 and TemperatureSource of graphic: Hansen, J et. al. Climate Change and Trace GasesThe correlation between temperature and CO2 in the atmosphere over the last 450,000 years is very goodEven if voluntary emissions reductions were to succeed we must still get the CO2 out of the air. Carbon rationing is a frightening adjunct and alternative. Who will be the global police?The best plan is a holistic one that reduces emissions and profitably balances the inevitable releases from our activities with massive sequestration.
7 Water“1/3 of the world’s population are presently living in water stressed countries. Depending on the emission scenarios, climate scenarios and population change, it is estimated that up to 2/3 of the world’s population will be living in water stressed countries by 2050 as a result of climate change”Source of Graphic: Lean, Geoffrey, and Don Hinrichsen, Atlas of the Environment, Santa Barbara, CA: ABC-CLIO, Inc.Source: Defra (2004). Scientific and Technical Aspects of Climate Change, including Impacts, Adaptation and Associated Costs. UK, Department for Environment, Food and Rural Affairs
8 Tec and Eco-Cements use waste. Waste & PollutionIll health.Contamination of global commons with dangerous molecules.Increased traffic, noise, odours, smoke, dust, litter and pests.There are various estimates. The consensus is that we produce about billion tonnes of waste each year.Tec and Eco-Cements use waste.
9 One Planet, Many People, Many Interconnected Problems John Harrison Presentation AASMIC ConferenceOne Planet, Many People, Many Interconnected ProblemsTecEco are in the BIGGEST Business on the Planet – Economic Solutions to our Energy, Global Warming, Water and Waste Problems.
10 Urgent Fixes are Needed Water1/3 of world population stressed for waterBy /3 due to global warmingWasteAround 600 million tonnes.The underlying moleconomic flow is poisoning our worldCO2Causing global temperature risesEnergyPeak oil has passed and fossil fuel energy costs set to rise.All these problems are interconnectedTo solve these problems we need to change the way we do things and what we do them with!
11 John Harrison Presentation AASMIC Conference The Techno-ProcessBiosphereUnderlying the techno-process that describes and controls the flow of matter and energy through the supply and waste chains are molecular stocks and flows. If out of synch with earth systems these moleconomic flows have detrimental affects.GeosphereDetrimental affects on earth systemsWasteTakeMove billion tonnes Use some 50 billion tonnesMaterialsManipulateMaterialsMake and UseAnthroposphereTHE TECHNO-PROCESSMost of you will have by now come to realise that there is a process often described as the “take use waste process” that I call the techno process. Unfortunately there are affects on global systems that are detrimental.To reduce the impact on earth systems new technical paradigms need to be invented and cultural changes evolve that result in materials flows with underlying molecular flows that mimic or at least do not interfere with natural flows and that support rather than detrimentally impact on earth systems.
12 Atmosphere Biosphere Geosphere Hydrosphere The Earth SystemThe earth system consists of positive and negative feedback loops.Small changes caused by man such as CO2 and other climate forcing as well as pollution impact right across all interconnected systems throughout the global commons.AtmosphereAnthropo-sphereBiosphereGeosphereHydrosphere
13 Earth Systems Science Earth Systems Atmospheric composition, climate, land cover, marine ecosystems, pollution, coastal zones, freshwater salinity etc.Source graphic: NASAEarth system science treats the entire Earth as a system in its own right, which evolves as a result of positive and negative feedback between constituent systems (Wiki). These systems are ideally homeostatic.
14 Detrimental Impacts of the Techno-Process Detrimental Linkages that affect earth system flowsTake manipulate and make impactsEnd of lifecycle impactsUse impacts. Materials are in the Techno-Sphere Utility zoneThere is no such place as “away”Materials are everything between the take and waste and affect earth system flows.Greater UtilityLess Utility
15 Under Materials Flows in the Techno-Processes are Molecular Flows John Harrison Presentation AASMIC ConferenceUnder Materials Flows in the Techno-Processes are Molecular FlowsTake → Manipulate → Make → Use → Waste[ ←Materials flow→ ][ ← Underlying molecular flow → ]If the underlying molecular flows are “out of tune” with nature there is damage to the environment e.g. heavy metals, cfc’s, c=halogen compounds and CO2Moleconomics is the study of the form of atoms in molecules, their flow, interactions, balances, stocks and positions. 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. These flows should mimic, balance or minimally interfere with natural flows.MOLECONOMIC FLOWSUnderlying the flow of materials through the techno process is a moleconomic flow of molecules that is out of tune with the rest of the planet and causing damage to the environment. If you want to know more about the science of moleconomics please go to our web site and look under projects.To fix the molecular flows that are impacting our planet we must first fix the materials flows in a bottom up approach
16 Innovative New Materials - the Key to Sustainability Materials are what builders useThe 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.By changing how we make “things” and what we make them with we can fix the underlying molecular flows that are destroying the natural homeostasis of our planet
17 Economically Driven Sustainability John Harrison Presentation AASMIC ConferenceEconomically Driven SustainabilityNew, more profitable technical paradigms are required that result in more sustainable and usually more efficient moleconomic flows that mimic natural flows or better, reverse our damaging flows.ECONOMICALLY DRIVEN SUSTAINABILITYOur approach must not only be holistic, but also economic if we are to have any hope of success.Working for sustainability market forces will make all the difference.The challenge is to move the supply and demand of resources towards more sustainable outcomes by stimulating and harnessing human behaviours which underlay economic demand phenomena, through cultural change push by governments and other leaders, and real improvement in technical and other properties as I will explain in the next slide.Sustainable processes like the new TecEco technologies are more efficient and therefore more economic.$ - ECONOMICS - $Change is only possible economically. It will not happen because it is necessary or right.
18 Consider Sustainability as Where Culture and Technology Meet John Harrison Presentation AASMIC ConferenceConsider Sustainability as Where Culture and Technology MeetIncrease in demand/price ratio for greater sustainability due to cultural change.$SupplyEquilibriumShiftGreater Value/for impact (Sustainability) and economic growthECONOMICSWe must rapidly move both the supply and demand curves for sustainabilityDemandIncrease in supply/price ratio for more sustainable products due to technical innovation.#CULTURAL CHANGE AND PARADIGM SHIFTS IN TECHNOLOGYChanges in the market interaction of demand and supply reducing energy and resource usage and detrimental linkages with the planet can be achieved through cultural change and innovative changes in the technical paradigm.A measure of the degree of sustainability is where the demand for more sustainable technologies is met by their supply.
19 Changing the Technology Paradigm John Harrison Presentation AASMIC ConferenceChanging the Technology ParadigmIt is not so much a matter of “dematerialisation” as a question of changing the underlying moleconomic flows. We need materials that require less energy to make them, do not pollute the environment with CO2 and other releases, last much longer and that contribute properties that reduce lifetime energies. The key is to change the technology paradigms“By enabling us to make productive use of particular raw materials, technology determines what constitutes a physical resource1”Pilzer, Paul Zane, Unlimited Wealth, The Theory and Practice of Economic Alchemy, Crown Publishers Inc. New York.1990Or more simply – the technical paradigm determines what is or is not a resource!
20 Cultural Change is Happening! Al Gore (SOS)CSIRO reportsSTERN ReportLots of TalkfestIPCC ReportPolitical changeBranson PrizeLive Earth (07/07/07)The media have an important growing role
21 Changing the Techno-Process John Harrison Presentation AASMIC ConferenceChanging the Techno-ProcessTake => manipulate => make => use => wasteDriven by fossil fuel energy with detrimental environmental effects.By changing the technology paradigms we can change the materials flows and thus the underlying molecular flows.Reduce Re-use RecycleThis is biomimicry!INDUSTRIAL ECOLOGY – CHANGING THE TECHNO-PROCESSI am sure you will have all heard of the three R’s. Reduce, reuse and recycle, to which some add re-make.Industrial ecology, the idea that the waste output of one kind of activity can be resource input for another, is most easily achieved in the construction industry.The materials used determine many properties including weight, embodied energies, fuel related and chemical emissions, lifetime energies, user comfort and health, use of recycled wastes, durability, recyclability and the properties of wastes returned to the bio-geo-sphere. If you cannot recycle for chemical property recycle on the basis of physical properties the material would contribute to a composite.There is huge scope for sequestration and conversion of waste to resource given the massive size of the materials flows involved in the built environment. With the right materials technology, because of its sheer size, the built environment could reduce the take from the bio-geo-sphere and utilise many different wastes including carbon dioxide<= Materials =>Atoms and Molecules in the global commonsMoleconomics
22 Learning from Nature (Biomimicry) John Harrison Presentation AASMIC ConferenceLearning from Nature (Biomimicry)Nature is the most frugal economist of all.The waste from one plant or animal is the food or home for another.In nature photosynthesis balances respiration and recycling is the normBy studying nature “we learn who we are, what we are and how we are to be.” (Wright, F.L. 1957:269)There is a strong need for similar efficiency and balance in our techno-processBy learning from Nature we can all live togetherBIOMIMICRYThe philosophy and chemistry of TecEco technology is backed by the greatest and longest experiment of all time – that of life on this planet.Little is wasted in nature, the waste from one living thing being the home or food for another.We must, like nature, devise ways of using carbon dioxide and other wastes.
23 Biomimicry - Geomimicry John Harrison Presentation AASMIC ConferenceBiomimicry - GeomimicryThe term biomimicry was popularised by the book of the same name written by Janine BenyusBiomimicry 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.Geomimicry is similar to biomimicry but models geological rather than biological processes.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 and very little of energy.Geomicry is a natural extension of biomimicry and applies to geological rather than living processesAll natural processes are very economical. We must also be MUCH more economical
24 Biomimicry - Ultimate Recyclers John Harrison Presentation AASMIC ConferenceBiomimicry - Ultimate RecyclersAs peak oil starts to cut in and the price of transport rises sharplyWe should not just be recycling based on chemical property requiring transport to large centralised sophisticated and expensive facilitiesWe should be including CO2 and wastes based on physical properties as well as chemical composition in composites whereby they become local resources.Jackdaws and bower bird recycle all sorts of things they find nearby based on physical property. The birds are not concerned about chemical composition and the nests they make could be described as a composite materials.TecEco cements are benign binders that can incorporate all sort of wastes without reaction problems. We can do the same as the Jackdaw or bower bird
25 Localized Low Transport Embodied Energy Materials John Harrison Presentation AASMIC ConferenceLocalized Low Transport Embodied Energy MaterialsNo longer an option?As the price of fuel rises, the use of on site low embodied energy materials rather than transported aggregates will have to be considered. We will have to mimic the jackdaw or bower bird. Gaia engineering can be implemented everywhere.
26 Utilizing Carbon and Wastes John Harrison Presentation AASMIC ConferenceUtilizing Carbon and WastesDuring 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 calcium and magnesium carbonate materials and other wastes in the built environment mimics nature in that carbon is used in the homes or skeletal structures of most plants and animals.CO2In eco-cement concretes the binder is carbonate and the aggregates are preferably carbonates and wastes. This is “geomimicry”CO2BIOMIMICRYThe philosophy and chemistry of TecEco technology is backed by the greatest and longest experiment of all time – that of life on this planet.Little is wasted in nature, the waste from one living thing being the home or food for another.We must, like nature, devise ways of using carbon dioxide and other wastes.CO2CCO2WastePervious pavement
27 John Harrison Presentation AASMIC Conference GeomimicryThere are grams of magnesium and about .4 grams of calcium in every litre of seawater.There is enough calcium and magnesium in seawater with replenishment to last billions of years at current needs for sequestration.To survive we must build our homes like these seashells using CO2 and alkali metal cations. This is geomimicryCarbonate sediments such as these cliffs represent billions of years of sequestration and cover 7% of the crust.
28 Geomimicry for Planetary Engineers? John Harrison Presentation AASMIC ConferenceGeomimicry for Planetary Engineers?Large tonnages of carbon (7% of the crust) were put away during earth’s geological history as limestone, dolomite and magnesite, mostly by the activity of plants and animals.Much more than in coal or petroleum!Shellfish built shells from carbon and trees turn it into wood.These same plants and animals wasted nothingThe waste from one is the food or home for another.Because of the colossal size of the flows involved the answer to the problems of greenhouse gas and waste is to use them both.
29 Geomimicry for Planetary Engineers? John Harrison Presentation AASMIC ConferenceGeomimicry for Planetary Engineers?Such a paradigm shift in resource usage will not occur because it is the right thing to do.It can only happen economically.We must put an economic value on carbon and wastesinventing new technical paradigms such as offered by TecEco and the Global Sustainability Alliance in Gaia Engineering.Evolving culturally to effectively use these technical paradigmsBy using carbon dioxide and other wastes as building materials we can economically reduce their concentration in the global commons.Materials are very important!
30 Why Magnesium Carbonates? Because of the low molecular weight of magnesium, it is ideal for scrubbing CO2 out of the air and sequestering the gas into the built environment:More CO2 is captured than in calcium systems as the calculations below show.At 2.09% of the crust magnesium is the 8th most abundant elementSea-water contains 1.29 g/l compared to calcium at .412 g/lMagnesium materials from Gaia Engineering are potential low cost. New kiln technology from TecEco will enable easy low cost simple non fossil fuel calcination of magnesium carbonate to make binders with CO2 recycling to produce more carbonate building material to be used with these binders.Magnesium compounds have low pH and polar bond in composites making them suitable for the utilisation of other wastes.
31 John Harrison Presentation AASMIC Conference Making Carbonate Building Materials to Solve the Global Warming ProblemHow much magnesium carbonate would have to be deposited to solve the problem of global warming?The annual flux of CO2 is around 12 billion tonnes ~= billion tonnes magnesiteThe density of magnesite is 3 gm/cm3 or 3 tonne/metre322.9/3 billion cubic metres ~= 7.63 cubic kilometres of magnesite would have to be deposited each year.Compared to the over seven cubic kilometres of concrete we make every year, the problem of global warming looks surmountable.If magnesite was our building material of choice and we could make it without releases as is the case with Gaia Engineering, we have the problem as good as solved!We must build with carbonate and waste
32 Why Materials for the Built Environment? John Harrison Presentation AASMIC ConferenceWhy Materials for the Built Environment?The built environment is made of materials and is our footprint on earth.It comprises buildings and infrastructure.Construction materials comprise70% of materials flows (buildings, infrastructure etc.)40-50% of waste that goes to landfill (15 % of new materials going to site are wasted.)Around 25 billion tonnes of building materials are used annually on a world wide basis.Mostly using virgin natural resourcesCombined in such a manner that they cannot easily be separated.Include many toxic elements.THE IMPORTANCE OF MATERIALSMaterials are our footprint on the planet and of first consideration in our quest to devise ways of using carbon dioxide and other wastes.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.)Why not use magnesium carbonate building components from Greensols and Eco-Cements from TecEco to bind them together?
33 The Built Environment and Global Sustainability The built environment is our footprint, the major proportion of the techno-sphere and our lasting legacy on the planet. It comprises buildings and infrastructureSource of graphics: Nic Svenningson UNEP SMB2007
34 Building is Going Balistic! Source of graphic: Rick Fedrizzi SMB 2007The relative impact of the built environment is rising as the East catches up with the West!
35 Huge Potential for More Sustainable Construction Materials John Harrison Presentation AASMIC ConferenceHuge Potential for More Sustainable Construction MaterialsReducing the impact of the take and waste phases of the techno-process by.including carbon in materials they are potentially carbon sinks.including wastes for physical properties as well as chemical composition they become resources.re engineering materials to reduce the lifetime energy of buildingsA durable low pH high bonding binder system is required for effective waste utilisation such as TecEco Tec and Eco-CementsMany wastes including CO2 can contribute to physical properties reducing lifetime energiesCO2CO2UTILISING WASTE IN CITIESTecEco advocate the development of materials that include waste based on physical as well as chemical properties and that reduce the lifetime energy of buildings by introducing new properties.CO2CCO2WastePervious pavement
37 The Gaia Engineering Tececology The Gaia Engineering tececology could be thought of as an open technical ecology designed to reverse major damaging moleconomic and other system flows outside the tececologyIndustrial Ecologies are generally thought of as closed loop systems with minimal or low impacts outside the ecologyThe Gaia Engineering tececology is not closed and is designed to reverse damaging moleconomic flows outside the ecology - LIKE A GIANT ECOLOGICAL PUMP
38 The Gaia Engineering Process John Harrison Presentation AASMIC ConferenceThe Gaia Engineering ProcessGaia Engineering delivers profitable outcomes whilst reversing underlying undesirable moleconomic flows from other less sustainable techno-processes outside the tececology.Inputs:Atmospheric or industrial CO2, brines, waste acid, other wastesOutputs:Carbonate building materials, potable water, gypsum, sodium bicarbonate and other valuable commodity salts.Carbonate building componentsCO2CO2Solar or solar derived energyCO2TecEco KilnTecEco MgCO2 CycleCO2Eco-CementMgOMgCO3Greensols Process1.29 gm/l Mg .412 gm/l CaCoalFossil fuelsCarbon or carbon compounds Magnesium compoundsOil
39 Gaia Engineering Introduction Gaia engineering is a combination of new technologies includingThe Greensols processTecEco’s Tec-Kiln technology and cementsCarbon dioxide scrubbing technologiesTecEco' Eco-CementsGaia engineering profitably geomimics past planetary geological processes and adopted on a large scale will:Sequester significant amounts of atmospheric CO2Add value to the salts recoverable from sea waterConvert large volumes of waste to valuable resourceProduce fresh water.
40 Gaia Engineering Summary Inputs includeSeawater or suitable brineCO2Waste acidOther wastes of all kindsA small amount of energyOutputs includeGypsum, sodium bicarbonate and various other valuable salts.Magnesium carbonate building components.TecEco Tec, Eco and Enviro-Cements.Waste utlisation.Fresh water.
41 John Harrison Presentation AASMIC Conference Gaia EngineeringGreensols Seawater Carbonation Process.1.354 x 109 km3 Seawater containing tonne Mg or suitable brines from other sourcesWaste AcidGypsum + carbon waste (e.g. sewerage) = fertilizersBicarbonate of Soda (NaHCO3)CO2 from power generation or industryOther salts Na+,K+, Ca2+,Cl-Gypsum (CaSO4)Sewerage compostSimplified TecEco Reactions Tec-Kiln MgCO3 → MgO + CO kJ/mole Reactor Process MgO + CO2 → MgCO kJ/mole (usually more complex hydrates)MgO Production using solar energyCO2 + H2O => Energy rich biomass using blue green algae(MgCO2) CycleCO2 from power generation, industry or out of the airMagnesite (MgCO3)Tec-Reactor Hydroxide / Carbonate slurry processMagnesia (MgO)Solar Process to Produce Magnesium MetalSequestration Table – Mg from SeawaterCO2Tonnes CO2 sequestered per tonne magnesium with various cycles through the TecEco Tec-Kiln process. Assuming no leakage MgO to built environment (i.e. complete cycles).Billion TonnesTonnes CO2 sequestered by 1 billion tonnes of Mg in seawaterTonnes CO2 captured during calcining (same as above)Tonnes CO2 captured by eco-cementTotal tonnes CO2 sequestered or abated per tonne Mg in seawater (Single calcination cycle).Total tonnes CO2 sequestered or abated (Five calcination cycles.)Total tonnes CO2 sequestered or abated (Ten calcination cycles).36.20Eco-Cement Tec-CementOther Wastes
42 John Harrison Presentation AASMIC Conference Gaia EngineeringGaia Engineering VECTORSThe Gaia Engineering process starts with either magnesium silicates or the Greensols process. In the case of silicates, magnesium carbonates are produced using proven mineral sequestration technology and then transferred to the MgCO3 cycle. The Greensols process on the other hand uses carbon dioxide from power stations and waste acid to extract magnesium carbonate and other salts from seawater or suitable brines and produces potable water as a by-product. The MgCO3 from either process is then calcined in the TecEco kiln which removes and captures carbon dioxide, ready for incorporation for example into cellulose or fuel made by genetically engineered blue green algae, and produces magnesium oxide. This magnesium oxide can either be used to make TecEco cements which in the case of eco-cement absorb more atmospheric CO2 as they harden or alternatively be used to sequester more CO2 in a hydroxide/carbonate slurry capture process.The MgCO3 produced by the hydroxide slurry process can be decarbonated and cycle around that process indefinitely as in this slide.Inputs Brines Waste Acid Wastes CO2Outputs Gypsum, Sodium bicarbonate, Salts, Building materials, Potable water
44 Greensols Carbon Capture The hydrogen bonding in water keeps oppositely charged ions from combining. Water “dissolves” them.Strongly charged ions such as calcium, magnesium and carbonate attract hydration shells of water around them. For example magnesium and calcium ions polar bond to oxygen and the negative carbonate ion polar bonds to hydrogen. These bonds can propagate through several layers of water and are strong enough to prevent the formation of calcium and magnesium carbonates even from supersaturated solutions.The Greensols process uses waste acid to de-polarise a statistical proportion of water molecules by attaching a proton to them whereby positively charged sodium, calcium or magnesium ions as well as negatively charged ions including carbonate ions are released, can combine and thus precipitate.
45 Greensols Carbon Capture John Harrison Presentation AASMIC ConferenceGreensols Carbon CaptureHydration shelling of water occurs around calcium or magnesium ions because of the strong charge of especially magnesium to the oxygen end of waterSimilar hydration shelling occurs around the negative carbonate ion through polar bonding to the hydrogen ends of water
46 Greensols Carbon Capture John Harrison Presentation AASMIC ConferenceGreensols Carbon CaptureThe addition of a proton to water using strong waste acid results in its de polarisation whereby it no longer electronically holds as many ions (sodium, calcium, magnesium or carbonate etc.) statistically releasing them and allowing them to combine and precipitate as carbonates and other more valuable salts leaving behind essentially fresh water
47 Greensols Carbon Capture John Harrison Presentation AASMIC ConferenceGreensols Carbon Capture+=Mg CO3_ _ => MgCO3The statistical release of both cations and anions results in precipitation of for example magnesium carbonate as shown above.
48 Advantages of Greensols over Reverse Osmosis John Harrison Presentation AASMIC ConferenceAdvantages of Greensols over Reverse OsmosisGREENSOLSREVERSE OSMOSIS DE-SALINATIONLow energy costs - Does not work against the electronic forces in water.Relatively high energy costs- Works against the hydrogen bonding of water to separate it from its ionsLow maintenance- The plant consists of low cost replaceable pumpsHigh Maintenance- The membranes need cleaning and changing at regular intervals.No damaging or dangerous outputsHighly saline water is potentially damagingValue adds include fresh water, sequestration, valuable salts and building productsThe only value add is fresh waterTell somebody with influence today!
49 The Tec-Reactor Hydroxide Carbonate Slurry Process John Harrison Presentation AASMIC ConferenceThe Tec-Reactor Hydroxide Carbonate Slurry ProcessThe solubility of carbon dioxide gas in seawaterIncreases as the temperature approached zero andIs at a maxima around 4oCThis phenomenon is related to the chemical nature of CO2 and water andCan 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
50 The MgCO2 Process (Magnesium Thermodynamic Cycle) John Harrison Presentation AASMIC ConferenceThe MgCO2 Process (Magnesium Thermodynamic Cycle)The MgCO2 (magnesium thermodynamic cycle) is very important for sequestration and results in the formation of valuable building productTOTAL CALCINING ENERGY Relative to MgCO3 Theoretical = 1480 kJ.Kg With inefficiencies = 1948 kJ.Kg-1Tec-KilnCO2 + H2O => Hydrocarbons compounds using algaeCO2MagnesiteDehydrationEco-CementsCalcinationRepresentative of other hydrated mineral carbonatesCalcification MgCO3 => MgO + CO2 ΔH = kJ.mol-1 ΔG = kJ.mol-1MagnesiaNesquehoniteCarbonation Mg(OH)2.nH2O +CO2 +2H2O => MgCO3.3H2O ΔH = kJ.mol ΔG = kJ.molCarbonationHydration MgO + H2O => Mg(OH)2.nH2O ΔH = kJ.mol ΔG = kJ.molBruciteTec, Eco and Enviro-Cements
51 The TecEco Tec-Kiln Technology John Harrison Presentation AASMIC ConferenceThe TecEco Tec-Kiln TechnologyRuns at low temperatures minimising the development of lattice energy.Can be powered by various non fossil sources of energy such as solar energy or waste heat.CO2 + H2O => Hydrocarbons compounds using algaeMgO Production using solar energyGrinds and calcines at the same time thereby operating 25% to 30% more efficiently.Captures CO2 for return to the Greensols process, bottling or use for fuel manufacture using algae and other life forms or other purposes.The products – CaO and/or MgO can be used to sequester more CO2 in the MgCO2 process which can be repeated.Suitable for making the reactive MgO used in TecEco cements.CAPTURE OF CO2The capture of CO2 at source during the manufacturing process is easier for the calcination of magnesium carbonates than any other carbonate mainly because the process occurs at relatively low temperatures.TecEco Pty. Ltd. own intellectual property in relation to a new tec-kiln in which grinding and calcining can occur at the same time in the same vessel for higher efficiencies and easy capture of CO2.Provided sufficient uses can be found for pure CO2 produced during manufacture whereby it is also permanently sequestered, a system for sequestration on a massive scale using carbonates as building materials is very promising. Possibilities for alternative permanent disposal are in materials such as plastics or deep underground where CO2 reacts with country rock forming more carbonate.
52 Eco-Cement CO2 Release and Capture Eco-Cement – No Capture during ManufactureEco-Cement – With Capture during ManufactureCO2 capture (Greensols process etc)CO2H2OMgCO3.3H2OMgCO3.3H2OH2OH2OH2OCO2 from atmosphereMgOMgOMg(OH)2Mg(OH)2H2OH2OCarbon neutral except for carbon from process emissionsNet sequestration less carbon from process emissionsUse of non fossil fuels => Low or no process emissions
53 Gaia Engineering will Modify the Carbon Cycle CO2 in the air and waterCellular RespirationCellular Respiration burning and decayDecay by fungi and bacteriaPhotosynthesis by plants and algaeGaia Engineering, (Greensols, TecEco Kiln and Eco-Cements)Limestone coal and oil burningOrganic compounds made by heterotrophsOrganic compounds made by autotrophsConsumed by heterotrophs (mainly animals)
54 Outcomes from Gaia Engineering John Harrison Presentation AASMIC ConferenceOutcomes from Gaia EngineeringAs the proportion of man made carbonate used in the built environment increases.Critical 450 ppm, level =>Gaia Engineering CAN MAKE A REAL CONTRIBUTIONWe are even more excited about Gaia Engineering now we have modelled the possible contribution it could make to reducing CO2 in the airCO2 in the atmosphere will start to fall.These figures are obviously rubbery, but we hope you get the idea!
55 Emissions from Cement Production Chemical ReleaseThe process of calcination involves driving off chemically bound CO2 with heat.CaCO3 →CaO + ↑CO2Process EnergyMost 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).CO2 CO2Arguments 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.
56 Embodied Energy of Building Materials Concrete is relatively environmentally friendly and has a relatively low embodied energyDownloaded from (last accessed 07 March 2000)
57 Average Embodied Energy in Buildings Most of the embodied energy in the built environment is in concrete.Because so much concrete is used there is a huge opportunity for sustainability by reducing the embodied energy, reducing the carbon debt (net emissions), incorporating waste and improving properties that reduce lifetime energies.Downloaded from (last accessed 07 March 2000)
58 Cement Production ~= Carbon Dioxide Emissions Exponential growthTec, Eco and Enviro-Cements TecEco can provide a viable much more sustainable alternative.Source data: USGS Minerals Yearbook
59 John Harrison Presentation AASMIC Conference TecEco Binder SystemsSUSTAINABILITYPORTLANDPOZZOLANHydration 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 CEMENTSDURABILITYSTRENGTHTecEco concretes are a system of blending reactive magnesia, Portland cement and usually a pozzolan with other materials and are a key factor for sustainability.TECECO BINDER SYSTEMSI am now going to talk just a little about are binder systems which are basically a blending system between Portland and other hydraulic cement, reactive magnesia and, as required, a pozzolanREACTIVE MAGNESIAHydration of magnesia => brucite for strength, workability, dimensional stability and durability. In Eco-cements carbonation of brucite => nesquehonite, lansfordite and an amorphous phase for sustainability.
60 Tec & Eco-Cement Theory John Harrison Presentation AASMIC ConferenceTec & Eco-Cement TheoryPortlandite (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 andTecEco add reactive magnesiawhich hydrates, consuming significant water and concentrating alkalis forming Brucite which is another alkali, but much less soluble, mobile or reactive than Portlandite.In Eco-Cements brucite carbonates forming hydrated compounds with greater volume
61 John Harrison Presentation AASMIC Conference TecEco CementsTec-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.
62 John Harrison Presentation AASMIC Conference TecEco CementsEco-cements (High MgO)contain more reactive magnesia than in tec-cements. Brucite in permeable materials carbonates forming stronger fibrous mineral carbonates and therefore presenting huge opportunities for waste utilisation and sequestration. The low pH and high hydrogen bonding make Eco-Cements ideal for binding other materials including most wastes.Enviro-cements (High MgO)contain similar ratios of MgO and OPC to eco-cements but in non permeable 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.
63 Strength with Blend & Porosity John Harrison Presentation AASMIC ConferenceStrength with Blend & PorosityTec-cement concretesEco-cement concretesHigh PorosityEnviro-cement concretesHigh OPCHigh MagnesiaSTRENGTH ON ARBITARY SCALE 1-100
64 Converting Waste to Resource TecEco cements represent a cost affective option for using localised low impact materials and wastesReducing transports costs and emissionsMagnesium hydroxide in particular and to some extent the carbonates are less reactive and mobile and thus result in much more durable concretesLower solubilityLower reactivityBleed lessLower pHThe incredible stick as a result of polar bonding also adds to their ability to bind wastes.TecEco Technology - Converting Waste to Resource
65 Carbonation of Eco-Cements John Harrison Presentation AASMIC ConferenceCarbonation of Eco-CementsHave high proportions of reactive magnesium oxideCarbonate like lime but generally used in a 1:5-1:12 paste basis because much more carbonate “binder” is produced.Consider nesquehonite the main phase:MgO + H2O <=> Mg(OH)2 + CO2 + 2H2O <=> MgCO3.3H2Oliquid <=> gas <=> molar mass (at least!)liquid <=> gas <=> molar volumes (at least!)668% expansion relative to MgO or 308 % expansion relative to Mg(OH)2 (ex water or gas volume reduction)Total volumetric expansion from magnesium oxide to lansfordite is even more at 811%.MgO + H2O <=> Mg(OH)2 + CO2 + 4H2O <=> MgCO3.5H2OBecause magnesium has a low molecular weight, proportionally a much greater amount of CO2 is captured per mole of MgO than lime or any other carbonate.Carbonation adds considerable strength and some steel reinforced structural concrete could be replaced with fibre reinforced porous carbonated concrete.Mostly CO2 and waterAs Fred Pearce reported in New Scientist Magazine (Pearce, F., 2002), “There is a way to make our city streets as green as the Amazon rainforest”.
66 Carbonation is Proportional to Porosity an Time Carbonation RateTimeMacro Porosity
67 Eco-Cement Strength Development John Harrison Presentation AASMIC ConferenceEco-Cement Strength DevelopmentEco-Cements gain early strength from the hydration of PC.Later strength comes from the carbonation of brucite forming an amorphous phase, lansfordite and nesquehonite.Strength gain in Eco-Cements is mainly microstructural because ofMore ideal particle packing (Brucite particles at 4-5 micron are under half the size of cement grains.)The natural fibrous and acicular shape of magnesium carbonate minerals which tend to lock together.Both the carbonates and hydroxide of magnesium have strong polar bonding.
69 CO2 Abatement in Eco-Cement Blocks John Harrison Presentation AASMIC ConferenceCO2 Abatement in Eco-Cement BlocksFor 85 wt% Aggregates15 wt% CementPortland Cements 15 mass% Portland cement, 85 mass% aggregateEmissions .32 tonnes to the tonne. After carbonation. Approximately .299 tonne to the tonne.No Capture 11.25% mass% reactive magnesia, 3.75 mass% Portland cement, 85 mass% aggregate.Emissions .37 tonnes to the tonne. After carbonation. approximately .241 tonne to the tonne.Capture CO % mass% reactive magnesia, 3.75 mass% Portland cement, 85 mass% aggregate.Emissions .25 tonnes to the tonne. After carbonation. approximately tonne to the tonne.Capture CO2. Fly and Bottom Ash 11.25% mass% reactive magnesia, 3.75 mass% Portland cement, 85 mass% aggregate.Emissions .126 tonnes to the tonne. After carbonation. Approximately .113 tonne to the tonne.Eco-cements in porous products absorb carbon dioxide from the atmosphere. Brucite carbonates forming lansfordite, nesquehonite and an amorphous phase, completing the thermodynamic cycle.Greater SustainabilityCO2 ABATEMENT IN AN ECO-CEMENT BLOCKThe above slide shows that for an eco-cement concrete in a block which is 15% eco-cement if the eco-cement contains 75% reactive magnesia and with capture of CO2 during the manufacturing process and the use of a pozzolan after carbonation net emissions are less than a third as much..299 > .241 >.140 >.113 Bricks, blocks, pavers, mortars and pavement made using eco-cement, fly and bottom ash (with capture of CO2 during manufacture of reactive magnesia) have 2.65 times less emissions than if they were made with Portland cement.
70 TecEco Technology in Practice John Harrison Presentation AASMIC ConferenceTecEco Technology in Practice=> Earthship Brighton, UKBy Taus Larsen, (Architect, Low Carbon Network Ltd.)The Low Carbon Network (www.lowcarbon.co.uk) was established to raise awareness of the links between buildings, the working and living patterns they create, and global warming and aims to initiate change through the application of innovative ideas and approaches to construction. England’s first Earthship is nearly completed in southern England outside Brighton at Stanmer Park and TecEco technologies have been used for the floors and some walling.EARTHSHIP BRIGHTONThis slide shows the interior and exterior of Earthship Brighton in the UK which was the first building we were ever involved in.At Brighton we mainly used Eco-CementsEarthships are exemplars of low-carbon design, construction and living and were invented and developed in the USA by Mike Reynolds over 20 years of practical building exploration. They are autonomous earth-sheltered buildings independent from mains electricity, water and waste systems and have little or no utility costs.For information about the Earthship Brighton and other projects please go to the TecEco web site.
71 Earthship BrightonThe first building in the world made with Eco-Cement which sets by absorbing CO2 and wastes
72 Tec-Cement Slab Whittlesea, Vic. Australia => Tec-Cement Concrete SlabsOn 17th March 2005 TecEco poured the first commercial slab in the world using tec-cement concrete with the assistance of one of the larger cement and pre-mix companies.The formulation strategy was to adjust a standard 20 MPa high fly ash (36%) mix from the company as a basis of comparison.Strength development, and in particular early strength development was good. Interestingly some 70 days later the slab is still gaining strength at the rate of about 5 MPa a month.Also noticeable was the fact that the concrete was not as "sticky" as it normally is with a fly ash mix and that it did not bleed quite as much.Shrinkage was low. 7 days micro strains, 14 days micro strains, 28 days micros strains and at 56 days microstrains.
73 TecEco Technology in Practice - Whittlesea, Vic. Australia => Eco-Cement Mud BricksFirst Eco-cement mud bricks and mortars in AustraliaTested up twice as strong as the PC controlsMud brick addition rate 2.5%Addition rate for mortars 1:8 not 1:3 because of molar ratio volume increase with MgO compared to lime.
74 TecEco Technology in Practice – AMC Hire Tilt Up Panels => Tec-Cement Tilt UpsOur Tec-Cement concrete tilt ups are free of plastic cracking, obvious bleed marking and other defects.
75 Tec & Eco Cement Foamed Concretes Foamed TecEco cement concretes can be produced to about 30% weight reduction in concrete trucks using cellflow (or equivalents) or to about 70% weight reduction using a foaming machine with mearlcrete (or equivalents).BUILD LITE CELLULAR CONCRETE 4 Rosebank Ave Clayton Sth MELBOURNE AUSTRALIA 3169 PH FX
77 Tec & Eco Cement Foamed Concretes John Harrison Presentation AASMIC ConferenceTec & Eco Cement Foamed Concretes=> Foamed ConcretesRIGID STEEL FRAMINGThe panels fit together forming the outside cladding of a building as you put together the frame.Foam infill in steel frames.
78 TecEco Technology in Practice John Harrison Presentation AASMIC ConferenceTecEco Technology in Practice=> Topping CoatsTec-Cement concretes exhibit little or no shrinkage. At 10% substitution of MgO for PC the shrinkage is less than half normal. At 18% substitution with no added pozzolan there was no measurable shrinkage or expansion.SHRINK AND CRACKPROOF CONCRETEAt the new DJ motors in Hobart we poured some very difficult topping coats that were low or zero shrinkage.The above photo shows a tec-cement concrete topping coat (with no flyash) 20mm thick away from the door and 80 mm thick near the door. Note that there has been no tendency to push the tiles or shrink away from the borders as would normally be the case.
79 TecEco Technology in Practice John Harrison Presentation AASMIC ConferenceTecEco Technology in Practice=> Waterproofing RenderThe Clifton Surf Life Saving Club was built by first pouring footings, On the footings block walls were erected and then at a later date concrete was laid in between.As the ground underneath the footings was sandy, wet most of the time and full of salts it was a recipe for disaster.Predictably the salty water rose up through the footings and then through the blocks and where the water evaporated there was strong efflorescence, pitting, loss of material and damage.The TecEco solution was to make up a formulation of eco-cement mortar which we doctored with some special chemicals to prevent the rise of any more moisture and salt.The solution worked well and appears to have stopped the problem.CLIFTON SURF CLUBThe Clifton Surf Life Saving Club was built by first pouring footings, On the footings block walls were erected and then at a later date concrete was laid in between.As the ground underneath the footings was sandy, wet most of the time and full of salts it was a recipe for disaster.Predictably the salty water rose up through the footings and then through the blocks and where the water evaporated there was strong efflorescence, pitting, loss of material and damage.We are able to remedy the problem with a formulation of eco-cement mortar which we doctored with some special chemicals to prevent the rise of any more moisture and salt.The solution worked well and appears to have stopped the problem.
80 TecEco Technology in Practice John Harrison Presentation AASMIC ConferenceTecEco Technology in Practice=> Our First Slab Ever!Mike Burdon, Builder and Plumber.Mike works for a council interested in sutainability and has been involved with TecEco since around 2001 in a private capacity helping with large scale testing of TecEco tec-cements at our shack.Mike is interested in the potentially superior strength development and sustainability aspects.To date Mike has poured two slabs, footings, part of a launching ramp and some tilt up panels using formulations and materials supplied by John Harrison of TecEco. Mike believes that research into the new TecEco cements essential as he has found:The rheological performance even without plasticizer was excellent. As testimony to this the contractors on the site commented on how easy the concrete was to place and finish.The formulations are extremely easy to pump and place. Once in position they appeared to “gel up” quickly allowing stepping for a foundation to a brick wall.Strength gain was more rapid than with Portland cement controls from the same premix plant and continued for longer.The surfaces of the concrete appeared to be particularly hard and Mike attributes this to the fact that much less bleeding was observed than would be expected with a Portland cement only formulationMIKE BURDON’S MURDUNNA WORKSMike is a plumber and a friend of mine.We have built footings, two slabs and some tilt ups at his shack. All were significantly better than controls on the same site.
81 TecEco Technology in Practice John Harrison Presentation AASMIC ConferenceTecEco Technology in Practice=> Concrete Bricks, Blocks and PaversTecEco Tec and Eco-Cement bricks, blocks and pavers are now being made commercially in Tasmania and with freight equalization may be viable to ship to the mainland for your “green” project. Otherwise we may be able to get a local manufacturer to make them for you.BLOCK MAKINGIsland Block and Paver Pty. Ltd. are a shareholder in TecEco and have made both Tec and Eco-Cement blocks successfully for us.
82 TecEco Eco-Cement Permecocrete Allow many mega litres of good fresh water to become contaminated by the pollutants on our streets and pollute coastal waterwaysPermecocreteOrCapture and cleanse the water for our use?TecEco have now perfected porous pavements that can be made out of mono-graded recycled aggregates and other wastes and that sequester CO2.It does not get much greener!
83 TecEco Eco-Cement Permecocrete - Mimicking Nature Permecocrete is made with Eco-Cements that set by absorbing CO2 and can use recycled aggregates. It does not get any greener!Freedom from water restrictions – forever!Pure fresh water from your own block.Filtration through Permecocrete and water feature in garden will keep water pure and fresh.Cooler house and garden (cycle under slab for house cooling/heating option).Lower infrastructure costs for local council.Water feature keeps water cleanAll rainwater redirected to pavement filter.Permecocrete porous pavementPumpWater storage e.g. under drive
84 TecEco Permecocrete – Biomicking Nature Pavements are not just for vehicles. They must do much moreCO2CO2CO2CO2CO2CO2Cooling EvaporationSequestrationCleansing microbial activity and oxygenationMoisture retentionThe substrate must be properly designedOptional groundwater rechargeOptional impervious layer, underground drainage and storage. Dual water supply or parks etc. only.
85 Holistic Roads for the Future In Australia we run many duplicate services down each side of a road. Given the high cost of installing infrastructure it would be smarter to adopt a system whereby services run down the middle of a road down what amount to giant box culverts.Conventional bitumen or concrete footpath pavementPervious Eco-Cement concrete pavement (Permecocrete) surface using recycled aggregatesPervious gravel under for collection, cleansing and storage of waterServices to either side of the road. All in same trench of conduitService conduit down middle of roadFoamed Eco-Cement concrete root redirectors and pavement protectors. Roots will grow away from the foamed concrete because of its general alkalinity. It will also give to some extent preventing surface pavement cracking.Impermeable layer (concrete or plastic liner) angling for main flow towards collection drainsCollection drains to transport drain or pipe in service conduit at intervalsPossible leakage to street trees and underground aquifersIts time for a road re think!
86 So Far - Has Anything Really Changed? Building materials and methods have not really changed much in spite of all the pretense about sustainability.So far mostly green wash.Big improvements in our understanding of the importance of design butNo real paradigm shifts in technology with perhaps a few exceptionsNeon light globesSolar panels etc.To solve sustainability problems of the magnitude we have we must change the paradigm from the bottom up.We have to do things very differently!!TecEco’s answer is to convert waste and CO2 to resource by building with them.There is enormous scope for change in the built environment
87 Challenge in the Construction Business John Harrison Presentation AASMIC ConferenceThe challenge now facing people in the construction business is to:Implement sustainable materials in more sustainable ways.As builders of cities we havedense concentrations of peoplethe juxtaposition of many industriesconcentrations of materialsReal opportunities to reduce energy and material through-put!THE ROLE OF PROFESSIONALS IN THE CONSTRUCTION BUSINESSThe challenge now facing professionals in the construction business is to:understand materialsImplement them in more sustainable ways.The ability to design materials as products will change the relationship between scientists, architects and engineers.I am glad to see so many of you attending today.
88 What is Stopping Us? We are holding ourselves down! A lack of awarenessThe conservative nature of players in the industryPrescription standards, regulation etc.Lack of government leadershipPoliticsLegacy subsidies for non sustainable materials and practicesFailure by leaders in the market to buy sustainabilityEconomies of scaleShort term rather than long termA disconnect between builders and usersA chronic lack of skills in the industry to take up new more sustainable technologiesWe are holding ourselves down!We must change from the bottom up!
89 A Sustainable Built Environment John Harrison Presentation AASMIC ConferenceA Sustainable Built EnvironmentCO2 + H2O => Hydrocarbons compounds using bacteriaCO2OTHERWASTESCO2CO2PERMANENT SEQUESTRATION & WASTE UTILISATION (Man made carbonate rock incorporating wastes as a building material)Pareto’s principle -80% of the build environment in non structural and could be carbonate from Greensols held together by Eco-CementsGREENSOLSMgOECO-CEMENT CONCRETESMAGNESIUM CARBONATETECECO KILNRECYCLED BUILDING MATERIALS“There is a way to make our city streets as green as the Amazon rainforest”. Fred Pearce, New Scientist MagazineTECECO’S DREAMOur dream is to create cities that mimic nature in that have a balance of carbon, other wastes and energy.SUSTAINABLE CITIESMade with manufactured carbonate and waste!
90 John Harrison Presentation AASMIC Conference A Post – Carbon AgeECO-CEMENTSThe main magnesium carbonate that form in eco-cement is nesquehonite which is 83 mass % water and CO2 – cheap binder? Lansfordite, another mineral that forms has even more water in it!Magnesium carbonates are generally fibrous and acicular and therefore add microstructural strength.The long term pH is much lower than Portland cement concretes. Combined with the fact that magnesium minerals seem to stick well to other materials the result is that a high proportion of wastes can be included.As mentioned earlier TecEco cements are generally also much more durable. Materials that last longer are much more sustainableAs Fred Pearce reported in New Scientist Magazine (Pearce, F., 2002), “There is a way to make our city streets as green as the Amazon rainforest”.