Energy and Climate Change Challenges and Opportunities in the South African Cement Industry

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1 Energy and Climate Change Challenges and Opportunities in the South African Cement Industry Egmont Ottermann SAHF Conference Cape Town, October 2010

2 Pretoria Portland Cement Founded in 1892 as De Eerste Cement Fabriken Beperkt and opens operations at Hercules in Pretoria Opens Slurry Factory near Mafikeng in PPC operates in South Africa, Zimbabwe and Botswana with a cement capacity of over 7 Million tons of cement and lime products 7 Cement Operations, a Slag Mill and the largest lime plant in the Southern Hemisphere Known in South Africa as The Passionate People s Company

3 Peak Oil? Introduction Is Climate Change Real? There is no debate A reflection on the whale oil crisis Are we causing it? Even if there is technical debate, climate change is an scientific, political and business reality.

4 Climate Change So what? Does Climate Change matter to someone without a house?

5 Climate Change - Perspective Climate Change will impact especially the poor s will be resource constrained Peak Oil, Water Scarcity, Energy Shortages Truth Climate Change action saves money!! Energy Efficient Design Thermally Massive North Facing Insulation Systems Thinking in community development Water Energy Transportation

6 Sustainable Housing Longevity The Moral of a Fable A properly built house lasts longer

7 Cement The Basics

8 Main Components Calcareous Component Provides Lime (CaO) Limestone Marly limestone Chalk Coral limestone Marble Lime-sand Shell deposits Lime sludge Argillaceous Components (SiO 2 Al 2 O 3 and Fe 2 O 3 ) Clay Shale Calcareous marl Marl Marlyclay Tuff, ash Phyllite, slate Glass Typically shale provides the argillaceous components: Silica (SiO( 2, Aluminum(Al 2 O 3 ) & Iron (Fe( 2 O 3 ) Limestone provides the calcareous component: Calcium Carbonate (CaCO 3 ) Raw materials may vary in both composition and morphology.

9 Quarrying

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12 Raw Meal Preparation Preblending Raw mix preparation Grinding Raw meal homogenization

13 Stacking and Reclaiming

14 Clinkering in short There are five jobs to be done Drying Preheating Calcining Sintering Cooling 60% Fuel Split 40% Preheater Precalciner Kiln

15 Raw meal CaO/CaCO 3 SiO 2 Fe Al 2 O 3 Pre-calciner Gases: ~1200 C Raw meal: ~900 C Combustion gases: C Time > sec at >1450 C Clinker : 1450 C C > 15 min. Gases self-cleaning (CaO) No ash All minerals in final product

16 Mineralogical View of Cement Cement from ASPDEN Cement (1832) Cement from 1998 C3S Alite C2S Belite

17 Cement Milling

18 The Carbon Footprint of a Typical House

19 Concrete Carbon Footprint

20 Mitigating Climate Change Potential South African Cement Wedges Classical Wedges Cement Extension Clinker Mineralisation Alternative and Biomass Fuels Waste Heat Recovery Energy Use O 2 enrichment Novel Wedges Algae Cultivation Carbon Capture and Storage Novel Low Carbon Cements

21 Classical Wedges Cement Extension Widely practiced South Africa, with CEM III, IV and V cements being produced, in addition to the traditional OPC. Easiest to implement as a climate mitigation tool, but does not mitigate the emissions from clinker directly. Clinker Mineralisation Potential for improvement in thermal efficiency, but carries with it the risk of increased kiln instability and severe impact on the process. CaF 2 sources are limited and expensive in South Africa Unlikely to be a significant wedge

22 Classical Wedges Biomass Fuels Low energy costs in South Africa, with low landfill fees, have prevented the large scale implementation of biomass waste fuels. Rapidly increasing fuel costs will drive the search for alternatives. Increasing focus on biomass waste fuels in the coming decade due to landfill capacity and focused environmental legislation. Significant Potential is the legislative and permitting hurdles can be overcome Energy Use Upgrades and equipment replacement will result in significant improvements in the energy efficiency of plant in the next two decade

23 Classical Wedges Waste Heat Recovery Three processes known; Kalina, Organic Rankine and Steam Applications mainly in countries with electrical energy security problems Up to 25% reduction in electrical footprint possible, depending on kiln type and cooler technology O 2 enrichment Reduces dead air in a cement kiln process by increasing O 2 in the combustion air. Currently expensive, but new technology is reducing the cost of implementation. Significant Potential to increase thermal efficiency through a hotter flame and more fan capacity

24 Novel Wedges Algae Cultivation Potential Killer APP for climate change mitigation in cement. Technically proven on lab scale, but has scale up issues Two cement companies are researching pilot plants ACC Cement in India St Mary s Cement in Canada Algae Cultivation has the potential for carbon free clinker

25 Low Carbon Cements and Geopolymers Novel Low Carbon Cements Novacem / Calera / Calix Geopolymer Cements Rocktron / Cenin Largely ignored by the established cement companies up to now, so was the potential of mineral oil before commercialization

26 Energy and Climate Change A Tale of Winners and Losers What will you be? Lord AN Onymous looks back from 2050