Modern cements. Contents 15/06/2017. Colum McCague. What is Portland cement? Low carbon cements. Current position and outlook Conclusions

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1 Modern cements Colum McCague MPA Cement Concrete and Masonry Roadshow, Manchester, 15 th June 2017 Contents What is Portland cement? Carbon reduction strategy Low carbon cements EN cements Novel cements Current position and outlook Conclusions 1

2 Contents What is Portland cement? Carbon reduction strategy Low carbon cements EN cements Novel cements Current position and outlook Conclusions What is Portland cement? Manufacture Limestone and shale in kiln at 1450 C Significant thermal and electrical energy required for process CO 2 emitted from decomposition of limestone and burning of kiln fuel Energy and Carbon intensive! Image source: Cement Technology Roadmap: Carbon emissions reductions up to 2050, WBCSD and IEA,

3 What is Portland cement? SiO 2 argillaceous shale calcareous CaO Al 2 O 3, Fe 2 O 3 limestone What is Portland cement? SiO 2 C 2 S C 3 S CaO C 3 A Al 2 O 3, C 4 AF Fe 2 O 3 3

4 The UK carbon story Alternative fuels Fossil fuels CO 2 emissions (per tonne of cement production) have significantly reduced over past 30 years Calcination In 2015, UK emissions per tonne of cement had declined by 23% since 1998 levels UK Portland cement industry CO 2 emissions [1] [1] How do we reduce carbon? Alternative fuels Fossil fuels Modern plant/processes e.g. precalciner, milling technology Calcination Alternative raw materials e.g. pfa, iron components Alternative fuels e.g. biomass/tyre chips UK Portland cement industry CO 2 emissions [1] [1] 4

5 How can we meet our ambitious targets? emissions Improve and develop current approaches Scenario 1 tco 2e Scenario 1 tco 2e Develop and introduce Low carbon cements Carbon capture and storage/use MPA Cement 2050 strategy t [2] [2] Contents What is Portland cement? Carbon reduction strategy Low carbon cements EN cements Novel cements Current position and outlook Conclusions 5

6 Hierarchy of standards Source: Use of cement in concrete according to European standard EN 206-1, Müller, C EN Cement European cement standard published in 2000 Composition, specifications and conformity criteria for common cements E.g. CEM I, CEM II, CEM III.. 6

7 EN cements for UK concrete Up to 35% clinker substitution Up to 20% clinker substitution Up to 95% clinker substitution Up to 55% clinker substitution Extract from Table 1 of BS EN EN cements for UK concrete FA/Slag Narrow range of EN cements permitted in BS 8500 CEM III/C CEM III/B CEM III/A Rely heavily on FA and ggbs! CEM IV/B CEM II/B CEM II/A CEM I Clinker CEM II/A Can we optimise limestone?? Limestone 7

8 EN cements for UK concrete Ternary CEM II-M cements are available! CEM III/C CEM III/B FA/Slag MPA currently working with BSI to have CEM II-M cements approved in BS 8500 CEM II/B CEM II/A CEM I Clinker CEM III/A CEM IV/B CEM II/A CEM II/B-M CEM II/A-M Limestone EN cements for UK concrete FA/Slag Ternary CEM II-M cements are available! CEM III/C CEM III/B MPA currently working with BSI to have CEM II-M cements approved in BS 8500 CEM II/B CEM II/A CEM I Clinker CEM III/A CEM IV/B CEM II/A CEM VI CEM II/C-M CEM II/B-M CEM II/A-M Limestone 8

9 Contents What is Portland cement? Carbon reduction strategy Low carbon cements EN cements Novel cements Current position and outlook Conclusions What are novel cements? Burning of limestone is reduced Partial replacement in kiln with other minerals e.g. bauxite (calcium aluminate cement) Burning of limestone is eliminated Full replacement in kiln with other minerals e.g. magnesite (magnesia cements) Chemical activation of cementitious materials e.g. alkali activated slag cements 9

10 Novel cements? Magnesia cement invented in 1866 Alkali-activated slag invented in 1895 Calcium aluminate cement invented in 1908 What are we looking for? Lower CO 2 than Portland based cements Good efficiency of plant and processes Good availability of raw materials Similar performance and characteristics to Portland cement 10

11 To recap.. SiO 2 Portland cement Limestone + shale in kiln at up to 1450 C CEM I CaO Al 2 O 3 Novel cements (in brief) Calcium aluminate cement (e.g. ciment fondu) SiO 2 Less limestone + bauxite in kiln at up to 1600 C CEM I alternative? x CO 2 savings are negligible x Bauxite availability CAC CaO Al 2 O 3 11

12 Novel cements (in brief) Calcium silicate cement (e.g. Solidia cement) SiO 2 Less limestone + quartz in kiln at 1200 C CSC Cured by reaction with CO 2 CEM I alternative? 30% reduction in CO 2 up to 70% after sequestration! ~ Limited to precast CAC CaO Al 2 O 3 Novel cements (in brief) Calcium hydrosilicate cement (e.g. Celitement) Less limestone in kiln at 1000 C Lime + quartz interground and treated in autoclave CEM I alternative? 50% reduction in CO 2 ~ Slow production rate SiO 2 CSC CHC CAC CaO Al 2 O 3 12

13 Novel cements (in brief) Calcium sulfoaluminate cements (e.g. Aether, ALI CEM) SiO 2 Less Limestone, bauxite + gypsum in kiln at 1300 C CSC CHC CEM I alternative? 25-30% reduction in CO 2 Identical plant/processes to ~ Up to 10% more alumina required CaO CSAC CAC Al 2 O 3 Novel cements (in brief) Alkali activated materials (e.g. Cemfree) Calcium and silicon-rich (e.g. ggbs) or aluminium and silicon-rich (e.g. pfa) materials combined with alkali activator CEM I alternative? 9-80% reduction in CO [3] 2 ~ Raw material availability SiO 2 CSC mk CHC ggbs CSAC CAC CaO Al 2 O 3 [3] Handbook of Alkali-Activated Cements, Chindaprasit, P. and Leonelli, C. (eds),

14 Novel cements (in brief) Alkali activated materials (e.g. Cemfree) Calcium and silicon-rich (e.g. ggbs) or aluminium and silicon-rich (e.g. pfa) materials combined with alkali activator CEM I alternative? 9-80% reduction in CO [3] 2 ~ Raw material availability SiO 2 CSC mk CHC ggbs CSAC CAC CaO Al 2 O 3 [3] Handbook of Alkali-Activated Cements, Chindaprasit, P. and Leonelli, C. (eds), Novel cements (in brief) SiO 2 Geopolymer cement (e.g. BanahCEM, E-crete) Low-calcium alkali activated system [3] CSC CHC ggbs mk CEM I alternative? 9-80% reduction in CO [3] 2 ~ Raw material availability CSAC CAC CaO Al 2 O 3 [3] Handbook of Alkali-Activated Cements, Chindaprasit, P. and Leonelli, C. (eds),

15 Novel cements (in brief) SiO 2 Geopolymer cement (e.g. BanahCEM, E-crete) Low-calcium alkali activated system [3] CSC CHC ggbs Geopolymer cement mk CEM I alternative? 9-80% reduction in CO [3] 2 ~ Raw material availability CSAC CAC CaO Al 2 O 3 [3] Handbook of Alkali-Activated Cements, Chindaprasit, P. and Leonelli, C. (eds), Contents What is Portland cement? Carbon reduction strategy Low carbon cements EN cements Novel cements Current position and outlook Conclusions 15

16 CO 2 e of common cements vs. alternatives CEM I CEM II/A-L CEM II/B-V CEM III/A CEM IV/B-V SABC C C CHC AAM Standards development Drafting of European standards for SABC (e.g. Aether) now underway PAS 8820 (UK) for alkali activated and geopolymer cement published in April 2016 Sponsored by HS2 16

17 MPA outlook.. UK cement companies are currently considering uptake/implications of emerging alternative cements However until standards are devised the main focus is to further reduce emissions through improvements to current production processes Contents What is Portland cement? Carbon reduction strategy Low carbon cements EN cements Novel cements Current position and outlook Conclusions 17

18 Conclusions Modern Portland cements are becoming more sustainable due to ongoing improvements in plant and processes Development of Codes and Standards will encourage UK cement companies to develop alternative/novel cements for their product portfolios It is very unlikely that alternative cements will replace common Portland based cements but.. the cement industry is eager to embrace these new innovations where possible Thank you! 18