Presentation on theme: "An overview of Future Concretes"— Presentation transcript:
1An overview of Future Concretes An overview of the alternative mineral binder systems and composites made with them including novel concrete technologies addressing practical supply chain and economic issues including energy27/03/2017
2Why Future Concretes?What’s wrong with the concrete we use made with Portland Cement?Embodied energy and emissions, shrinkage, durability, placement, tensile strength etc. etc. Not optimised for lifetime energy reduction.We can make better more environmentally friendly materials but what about the cost?Better concretes don’t necessarily produce more and those producing them will make more money.Concrete made for purpose = Higher Margin?Architectural façade, insulative properties, permeable pavement etc.
3The Business ModelThe industry model is like Woolworths or Coles. Head on competition. Low margins resulting in a reliance on turnover volume and cost control to produce profits.This model is past its use by date."Firms need to embrace innovation to remain competitive. Future job creation will come as companies transform and adopt new practices. Putting it simply, firms that innovate will survive and be the market leaders of tomorrow." Source: Senator the Hon Kim Carr 24 Aug 2011The need to innovate under a carbon price and trading system is significantly greater than without.Given our problems the need to innovate goes beyond the immediate needs of the industry. There are other stakeholdersInnovation recognises new markets
4Making Money Through Innovation In Australia rules relating to the new R & D Tax Incentive have changed. The new scheme effective 1 July 2011 is more generous.Make a $1 and pay 30c corporate taxSpend a $1 to innovate thereby ensuring future profits and adding value to your balance sheet and the government will give you either 40 or 45c as a grant.That’s a c difference!Given the changes the industry business model needs to change.TecEco are also changing their business model. We are going to register as a Research Service Provider (RSP) and become more aligned with the University of Tasmania to attract student power under my supervision.The leverage provided by students will increase the value of investing in R & D to well over a dollar.
5What we Sell in the Industry Managers in the concrete industry seem to misunderstand what we sell.They think we sell Portland cement and concrete made with it.My analysis is that what we sell is the technical confidence in a liquid that sets as a solid material and it really would not matter what either was provided we could demonstrate technical merit and suitable properties.
6Increases in Business Performance from the Previous Year, by Innovation Status 2008-9
7Primary Production Process Build, & Manufacture Use Dispose Some of the Issues?The Techno ProcessPrimary Production Process Build, & Manufacture Use DisposeUnderlying Molecular FlowsPrimary ProductionMethane NOX & SOX Heavy Metals CO2 etc.Embodied & Process EnergyProcess, Build & ManufactureNOX & SOXHeavy Metals CO2 etc.Embodied & Process EnergyUseNOX & SOXHeavy Metals CO2 etc.Lifetime EnergyDispose or WasteMethane NOX & SOXHeavy Metals CO2 etc.Process Energy
8Predicted Global Cement Demand and Emissions Source: Quillin K. Low-CO2 Cements based on Calcium Sulfoaluminate [Internet]. Available from:
9Energy Outlook to 2035Source: U.S. Energy Information Administration. International Energy Outlook 2010 [Internet]. U.S. Energy Information Administration; 2010 [cited 2010 Sep 5]. Available from:
10Global Waste – An Underestimate! The challenge is to convert waste to resource.
11There are Huge Change Opportunities A wide variety of possible end uses with higher potential margins for which current solutions are sub-optimal.E.g. Addessing properties affecting lifetime energy.E.g. Mineral composites with higher “R” valueE.g. Particle boards made with mineral bindersE.g. Exterior structural panels with insulating propertiesHuge opportunities for reducing the cost base and improving the properties of concretes by focusing on the process by which they are made and what they are made with.A few tweaks to the formulationsMajor changes to the process and someLateral thinking in relation to aggregates.Every improvement counts but quantum improvements really matter – If implemented!Implementation issue because of the low level of skills in the industry
12Our Mantra Think outside the square. Spend more time thinking (R & D) less time doing (earning low margins).We cannot solve problems doing the same old thing in the same old way.The technology paradigm defines what is or is not a resource.Improvements through innovation = profit!Think whole of material and whole of systemRefine definition of what’s important and what is not
13Example of a Decision Matrix to Help us Improve the Future
14Future Cement Contenders Portland Cement Cements Based onProcessProcess CO2 (tonnes CO2 / tonne Compound )Decarbonat ion CO2 (tonnes CO2 / tonne Compound)Emissions (if no kiln capture– tonnes CO2 / tonne Compoun d)Emission s (kiln capture– tonnes CO2 / tonne Compoun d)Absorpti on (tonnes CO2 / tonne Compoun d, Assuming 100% carbonati on 1 year)Net Emissions (Sequestrat ion – No kiln Capture)(tonnes CO2 / tonne Compound, Assuming 100% carbonatio n 1 year)Example of Cement TypeApply toCommentNotesPCCurrent Methods.369 0.498.868None.001.867Split process lime with recapture then clinkerMost dense concretesNo supplementary cementitious or pozzolanic materials1Permeable Block formulation0.498.144.724Ordinary Portland CementSplit Process – Lime then clinker.368
15The Potential of CO2 Release and Capture - Portland Cements Split Process with Capture during ManufactureNo Capture during ManufactureCapture during ManufactureCO2 capture (e.g. N-Mg process etc.)CO2 capture (e.g. N-Mg process etc.)CO2 in atmosphereNet Emissions (Sequestration) Kg CO2/Kg productNet Emissions (Sequestration) kg CO2/kg productNet Emissions (Sequestration) kg CO2/kg productCaCO3 + ClaysCaCO3 + ClaysCaCO3H2OCaO + ClaysH2ONet Energy 3962 kJ/kg productH2ONet Energy 3962 kJ/kg productNet Energy 3962 kJ/kg productClinkerClinkerClinkerHydrated Cement PasteHydrated Cement PasteHydrated Cement PasteCarbon positive. Chemical and process emissionsCarbon positive. Chemical and process emissionsNet sequestration less carbon from process emissionsUse of non fossil fuels => Low or no process emissionsSource Data:
16Future Cement Contenders Mg Group Cements Based onProcessProcess CO2 (tonnes CO2 / tonne Compound)Decarbona tion CO2 (tonnes CO2 / tonne Compoun d)Emission s (if no kiln capture– tonnes CO2 / tonne Compou nd)Emission s (kiln capture– tonnes CO2 / tonne Compou nd)Absorpti on (tonnes CO2 / tonne Compou nd, Assumin g 100% carbonati on 1 year)Net Emission s (Sequestr ation) (tonnes CO2 / tonne Compou nd, Assumin g 100% carbonati on 1 year)Example of Cement TypeApply toCommentNotes<750 oCMgCO3.403 1.0921.495-1.092.-.688Eco-cement concrete, pure MgO concretes. Novacem concretesTecEco, Cambridge & NovacemTecEco Eco-Cement Force carbonated pure MgO3<450 oCMgCO3.3H2O.6931.784-.399Eco-cement concrete, pure MgO concretes. Novacem concretes?N-Mg route University of RomeMgCO3.3H2O Including capture during production of nesquehonite-2.184-1.491Silicate route ?NovacemAfter Klaus Lackner?Modified Ternary Blends (50% PC)Split Process – Lime (with capture) then clinker.185.002.183Ternary mix with MgO additive.Most dense concretesFaster setting and higher early strength2
17The Potential of CO2 Release and Capture Magnesium Carbonating System MgCO3 Route using TecEco Tec-KilnNo Capture during ManufactureWith Capture during Manufacture<7250CCO2 capture (e.g. N-Mg process etc.)CO2Net Emissions (Sequestration) kg CO2/kg productCO2 from atmosphereNet Emissions (Sequestration) Kg CO2/Kg productMgCO3MgCO3H2OH2OH2OH2ONet Energy 4084 kJ/kg productNet Energy 4084 kJ/kg productMgOMgOMg(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 emissionsSource Data:
18The Potential of CO2 Release and Capture Magnesium Carbonating System MgCO3.3H20 Route using TecEco Tec KilnNo Capture during ManufactureWith Capture during Manufacture<4200CCO2 capture (e.g. N-Mg process etc.)Net Emissions (Sequestration) kg CO2/kg productCO2CO2 from atmosphereNet Emissions (Sequestration) Kg CO2/Kg productMgCO3.3H2OMgCO3.3H2OH2OH2OH2OH2ONet Energy 7140 kJ/kg productNet Energy 7140 kJ/kg productMgOMgOMg(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 emissionsSource Data:
19Gaia Engineering kg CO2-e/kg product -1.092 -.399 >2 kg CO2-e/kg Mg product231Or similar. The annual world production of HCl is about 20 million tons, most of which is captive (about 5 million tons on the merchant market).
20The N-Mg Process A Modified Solvay Process for Nesquehonite Tec-Kiln HClNH3 and a small amount of CO2MgCO3.3H2OMg rich waterCO2Tec-KilnMgOAmmoniacal Mg rich waterH2OMg(OH)2MgOSteamMgCO3.3H2OFilterNH4Cl and a small amount of NH4HCO3FilterA Modified Solvay Process for Nesquehonite
21The Tec-Reactor Hydroxide Carbonate Capture Cycle The 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
22Gaia Engineering NH4Cl or HCl Portland Cement Manufacture CaOTecEco Tec-KilnIndustrial CO2MgOClaysBrine, Sea water, Oil Process water, De Sal Waste Water etc .TecEco Cement ManufactureGBFSN-Mg ProcessMgCO3.3H2OFly ashEco-CementsTec-CementsNH4Cl or HClFresh WaterBuilding components & aggregatesOther wastes
23Man Made Carbonate Aggregate? Source USGS: Cement PagesAssumptions % non PC N-Mg mix and Substitution by Mg Carbonate AggregatePercentage by Weight of Cement in Concrete15.00%Percentage by weight of MgO in cement6%Percentage by weight CaO in cement29%Proportion Cement Flyash and/or GBFS50%1 tonne Portland Cement0.867Tonnes CO2Proportion Concrete that is Aggregate85%CO2 captured in 1 tonne aggregate1.092
24Magnesium Carbonate Cements Magnesite (MgCO3) and the di, tri, and pentahydrates known as barringtonite (MgCO3·2H2O), nesquehonite (MgCO3·3H2O), and lansfordite (MgCO3·5H2O), respectively.Some basic forms such as artinite (MgCO3·Mg(OH)2·3H2O), hydromagnestite (4MgCO3·Mg(OH)2·4H2O) and dypingite (4MgCO3· Mg(OH)2·5H2O) also occur as minerals.We pointed out as early as 2001 that magnesium carbonates are ideal for sequestration as building materials mainly because a higher proportion of CO2 than with calcium can be bound and significant strength can be achieved.The significant strength is a result of increased density through carbonation (high molar volume increases) and the microstructure developed by some forms.
25TecEco Eco-CementsEco-Cements are blends of one or more hydraulic cements and relatively high proportions of reactive magnesia with or without pozzolans and supplementary cementitious additions. They will only carbonate in gas permeable substrates forming strong fibrous minerals. Water vapour and CO2 must be available for carbonation to ensue.Eco-Cements can be used in a wide range of products from foamed concretes to bricks, blocks and pavers, mortars renders, grouts and pervious concretes such as our own permeacocrete. Somewhere in the vicinity of the Pareto proportion (80%) of conventional concretes could be replaced by Eco-Cement.Left: Recent Eco-Cement blocks made, transported and erected in a week. Laying and Eco-Cement floor. Eco-Cement mortar & Eco-cement mud bricks. Right: Eco-Cement permeacocretes and foamed concretes
26TecEco Tec-Kiln, N-Mg route The calcination of nesquehonite has a relatively high enthalpy but there is significant scope for reducing energy using waste heatInitial weight loss below C consists almost entirely of water (1.3 molecules per molecule of nesquehonite). Between 100 and 1500C volatilization of further water is associated with a small loss of carbon dioxide (~3-5 %).From 1500C to 2500C, the residual water content varies between 0-6 and 0-2 molecules per molecule of MgC Above 3000C, loss of carbon dioxide becomes appreciable and is virtually complete by 4200C, leaving MgO with a small residual water content.Energy could be saved using a two stage calcination process using waste energy for the first stage.Dell, R. M. and S. W. Weller (1959). "The Thermal Decomposition of Nesquehonite MgCO3 3H20 And Magnesium Ammonium Carbonate MgCO3 (NH4)2CO3 4H2O." Trans Faraday Soc 55(10):
27Modified PC 50% Ternary Mix with N-Mg Route Mg Carbonate Aggregate 25-30% improvement in strengthFast first setBetter RheologyLess shrinkage – less crackingLess bleedingLong term durabilitySolve autogenous shrinkage?CriteriaGoodBadEnergy Requirements and Chemical Releases, Reabsorption (Sequestration?)Use >50% replacements and still set like “normal” concrete!Speed and Ease of ImplementationRapid adoption possibleBarriers to DeploymentPermissions and rewards systems seeCost/BenefitExcellent until fly ash runs out!Use of Wastes? or Allow Use of Wastes?Uses GBFS and fly ash and manufactured nesquehonite based aggregatePerformanceEngineeringExcellent all roundThermalHigh thermal capacityArchitecturalExcellentSafetyNo issuesAudience 1Audience 2
28Magnesium Phosphate Cements Chemical cements that rely on the precipitation of insoluble magnesium phosphate from a mix of magnesium oxide and a soluble phosphate.Some of the oldest binders known (dung +MgO)Potentially very greenif the magnesium oxide used is made with no releases or via the nesquehonite (N-Mg route) anda way can be found to utilise waste phosphate from intensive agriculture and fisheries e.g. feedlots. (Thereby solving another environmental problem)CriteriaGoodBadEnergy Requirements and Chemical Releases, Reabsorption (Sequestration?)The MgO used could be made without releasesThere is not much phosphate on the planetSpeed and Ease of ImplementationRapid adoption possibleIf barrier overcome (see below)Barriers to DeploymentPermissions and rewards systems see Must find a way to extract phosphate from organic pollution.Cost/BenefitEconomies of scale issue for MgO to overcomeUse of Wastes? or Allow Use of Wastes?With technology could use waste phosphate reducing water pollutionPerformanceEngineeringExcellent all roundThermalHigh thermal capacityArchitecturalSafetyNo issuesAudience 1Audience 2
29Sorel Type Cements and Derivatives Sorel Type Cements and Derivatives are all nano or mechano composites relying on a mix of ionic, co-valent and polar bonding.There are a very large number of permutations and combinations and thus a large number of patentsCriteriaGoodBadEnergy Requirements and Chemical Releases, Reabsorption (Sequestration?)The MgO used could be made without releasesSpeed and Ease of ImplementationMore could be usedIf barrier overcome (see below)Barriers to DeploymentNot waterproof even with modification.Cost/BenefitEconomies of scale issue for MgO to overcomeUse of Wastes? or Allow Use of Wastes?Not waterproofPerformanceEngineeringExcellent exceptNot waterpoof, salt affect metalsThermalHigh thermal capacityArchitecturalSafetyNo issuesAudience 1Audience 2
30Future Cement Contenders Cements Based onProcessProcess CO2 (tonnes CO2 / tonne Compound)Decarbon ation CO2 (tonnes CO2 / tonne Compoun d)Emission s (if no kiln capture– tonnes CO2 / tonne Compou nd)Emission s (kiln capture– tonnes CO2 / tonne Compou nd)Absorpt ion (tonnes CO2 / tonne Compou nd, Assumi ng 100% carbona tion 1 year)Net Emissions (Sequestr ation)(tonnes CO2 / tonne Compoun d, Assuming 100% carbonati on 1 year)Example of Cement TypeApply toCommentNotesCaOConventional.4530.7851.237-0.332Carbonating lime mortarCalera, British Lime Assn. & many othersSmall net sequestration with TecEco kiln1C3S?0.578>0.5783C2S0.511>0.511Belite cementChinese & othersC3A0.594>0.594Tri calcium aluminate cementIncreased proportionC4A3S0.216>0.216Calcium sulfoaluminate cementQuillin, K. and P. Nixon (2006). Environmentally Friendly MgO-based cements to support sustainable construction - Final report, British Research Establishment.
31Future Cement Contenders Cements Based onProcessProcess CO2 (tonnes CO2 / tonne Compound)Decarbon ation CO2 (tonnes CO2 / tonne Compoun d)Emission s (if no kiln capture– tonnes CO2 / tonne Compou nd)Emission s (kiln capture– tonnes CO2 / tonne Compou nd)Absorpt ion (tonnes CO2 / tonne Compou nd, Assumi ng 100% carbona tion 1 year)Net Emissions (Sequestr ation)(tonnes CO2 / tonne Compoun d, Assuming 100% carbonati on 1 year)Example of Cement TypeApply toCommentNotesAlakali Activated Ground Granulate d Blast Furnace Slag (GBFS)GBFS (“slag”) is a waste product from the manuf acture of iron and steelNil to cement industryGBFS with MgO activatorMany other activatorsPatented by TecEcoNot patented1Geo polymersFly ash + NaOH0.16Geopolymer Alliance,Geopolymer Institute, University Melbourne6
32CaO-Lime Criteria Good Bad Energy Requirements and Chemical Releases, Reabsorption (Sequestration?)The CaO used could be made withoutSpeed and Ease of ImplementationEasily implemented as no carbonation rooms etc reqd.Permissions and rewards systems seeBarriers to DeploymentWe need carbon trading!Cost/BenefitUse of Wastes? or Allow Use of Wastes?PerformanceEngineeringThermalEngineered thermal capacity and conductivity.ArchitecturalSafetyAn irritating dustAudience 1Audience 2
33GeopolymersCriteriaGoodBadEnergy Requirements and Chemical Releases, Reabsorption (Sequestration?)Low provided we do not run out of fly ashSpeed and Ease of ImplementationProcess issues to be overcomePermissions and rewards systems seeBarriers to DeploymentWe need carbon trading!Cost/BenefitUse of Wastes? or Allow Use of Wastes?PerformanceEngineeringGood but inconsistentThermalEngineered thermal capacity and conductivity.ArchitecturalSafetyCaustic liquorsAudience 1Audience 2Geopolymers as a future concrete suffer from two basic flaws on one very high riskFlaw. 1. The nanoporisity flaw which leads to durability problems and Flaw. 2. The fact that water is not consumed in the geopolymerisation process resulting in the almost impossible task of making them fluid enough for placement. Too much water reduces alkalinity and hence the high risk.
34Other ContendersSlag cements a variant of Portland cement as CSH is the main product.Supersulfated cements have potential as they are made mostly from GBFS and gypsum which are wastes and only a small amount of PC or lime. The main hydration product is ettringite and they show good resistance to aggressive agents including sulphate but are slow to set. (A derivative)Calcium aluminate cements are hydraulic cements made from limestone and bauxite. The main components are monocalcium aluminate CaAl2O4 (CA) and mayenite Ca12Al14O33 (C12A7) which hydrate to give strength. Calcium aluminate cements are chemically resistant and stable to quite high temperatures.Calcium sulfoaluminate cements & belite calcium sulfoaluminate cements are low energy cements that have the potential to be made from industrial by products such as low calcium fly ash and sulphur rich wastes. The main hydration product producing strength is ettringite. Their use has been pioneered in China (A derivative)
35Other ContendersBelite cements can be made at a lower temperature and contains less lime than Portland cement and therefore has much lower embodied energy and emissions. Cements containing predominantly belite are slower to set but otherwise have satisfactory properties. Many early Portland type cements such as Rosendale cement were rich in belite like phases. (a variant, SeePC - MgO – GBFS – fly ash blends. MgO is the most powerful new tool in hydraulic cement blends since the revelation that reactive magnesia can be blended with other hydraulic cements such as Portland cement % improvements in compressive strength and greater improvements in tensile strength, faster first set, better rheology and less shrinkage and cracking less bleeding and long term durability have been demonstrated. It is also possible autogenous shrinkage has been solved.MgO blended with other hydraulic cements, pozzolans and supplementary cementitious materials (SCM’s). Amazingly very little real research has been done on optimised blends particularly with cements other than Portland cement.