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Research and Technological Development in the

Cement and Concrete Industry

Sustainable Development: a Challenge for European Research

Parallel Session 7

Brussels, 26 May, 2009

Dr. Wolfgang Dienemann, HeidelbergCement Technology Center

Slide 2 - 26.05.2009Research and Technological Development in the Cement and Concrete Industry – W. Dienemann

The Cement and Concrete Industry

History

Cement like material already used by Romans (Opus Caementitum)

Development of hydraulic lime („Roman Cement“) late 18th / early 19th century

1843 – W. Aspdin develops Portland Cement

Since 1850s rapid industrial development



Facts and Figures

Concrete is the world‘s most versatile, durable and reliable construction material

In the same time concrete is a very economical product

Around 2,9 billion tonnes of cement in 2007

Equals 7 billion m3 of

concrete per year

Next to water concrete is

the most used material



Rising demand

Volumes are expected to more than double in the next decades

Infrastructure development in developing countries

China and India with high growth rates



Cement and CO2

Cement manufacturing releases ~800 kg CO2 per ton of cement

Around 60% results from chemical reaction of limestone

~40% burning of fuels, 5% electrical energy

Globally 5-7% of manmade CO2 emission

Key industry challenge


Technical Developments – Process Optimization

Optimizing Energy Efficiency

Energy accounts for ~40% of production costs

Optimization of burning process

– Efficiency of preheater

– Efficiency of cooler

– Waste heat power

generation



Valorization of Waste as Alternative Fuel

The clinker burning process is ideally suited to use alternative fuels

Minimized emissions due to long residence time and high gas temperatures

No residues as ash is incorporated in clinker

Overall reduction

of CO2 emissions

and fossil fuel

consumption



Valorization of Waste as Alternative Fuel

Significant progress has been made in replacing fossil fuels

Individual plants already use 90%

alternative fuels

Burning technology optimized

0

10

20

30

40

50

60

1987 1995 1999 2001 2003 2005 2007

Sha

re o

f al

tern

ativ

e fu

els

in %


Replacement of clinker

Clinker manufacturing accounts for 90% of fuel and energy consumption and CO2 emissions

Can partly be substituted by latent hydraulic or pozzolanic materials– Blastfurnace slag from steel industry

– Fly ash from coal fired power plants

– Natural and artificial pozzolans

Wide range of composite cements covered by EN standards




Conclusions

Three main pathways successfully applied in cement industry

Enabled through RTD and innovations in engineering technology and material science

Optimization of concrete recipes and manufacturing technology further reduced embodied energy

European companies clearly at the forefront of this development


Sustainability – Challenges and Opportunities

Reducing the Environmental Footprint High pressure to further reduce CO2-emission significantly

(Emission Trading) requires additional improvements and radical changes

Reduction of emission limits require further technological developments in process and filter technologies

Rising prices for electricity and fossil fuels demand further process optimization

Potential through incremental development limited due to high level of optimization already achieved


Adaptation to Climate Change

Optimized use of concrete‘s inherent thermal mass enables design of energy efficient buildings



Adaptation to Climate Change


Durable and safe construction needed also in case of extrem events to protect humans and economic values


Adaptation to climate change

Optimized cements and concretes required to better exploit alternative energy sources


Low-heat concrete for hydro dams

UHPC for offshore foundations

Special well cementfor deep drillings


Barriers to Change

Construction industry very conservative in general

High safety requirements for buildings and infrastructure, guaranteed longterm performance

High degree of regulation through Eurocodes, standards, etc

New products and applications must be scientifically sound and technically proven

This requires substantial investments in research and development



New Approaches – How can R&D help?

Increasing Biodiversity

Quarries are ideally suited to even increase biodiversity through dynamic and rare habitats– Rocks, steep faces– Wetland– Grasland– Standing water

R&D needed to develop biodiversity indicators and management plans


Increase use of Alternative Fuels even further

Valorization of waste only realistic possibility to reduce fossil fuel consumption (plus CO2-savings)

Assimilating more and new types of fuels requires RTD in– Burner technology (including O2-enrichment)

– Control of manufacturing process

– Impact on product quality

– Environmental performance (e.g. leaching)



Further reduce Clinker Content

Increasing the ratio of cementitious materials beyond today‘s values still is the most promising route short- and midterm.

Extending the use of conventional and new cementitious materials requires a better understanding of fundamental mechanisms that control performance:– Structural / mechanical behaviour

– Corrosion resistance

– Durability

– Environmental performance (e.g. leaching)



Developing new low-CO2 materials

For radical changes new materials are needed that have lower inherent CO2 content, i.e. less Calcium, e.g.:

– Supersulfated cements, based on slag

– Alkali-activated alumosilicates („geopolymers“)

– New, low Ca clinker, Belite, Ca-Sulfoaluminate

– MgO-based systems

– … Significant R&D activities required to understand their reaction

mechanism and predict their performance


Beton-prüfung


Knowledge based Development and Innovation

R&D in cement and concrete technology has been very fragmental, incremental and often trial-and-error based.

Needs to be converted into knowledge based approach:– Develop fundamental understanding of reaction mechanisms

– Develop and employ appropriate analytical tools

– Develop models to predict field performance

– Validate models vs field conditions

Holistic approaches needed to create confidence in new materials and overcome barriers in standardization; shorten time to market.

Cradle-to-Cradle concept might lead to new, creative approaches to develop positive footprint.



Conclusion

Significant improvements have been made to reduce environmental footprint of cement and concrete industry

Potential of current optimization pathes almost exploited Substantial RTD investments needed to further improve

sustainability of the industry.– In applied research, product development, innovation

– In basic research / fundamental understanding Potential to develop a positive footprint

Research and Technological Development in the Cement and Concrete Industry


for better building



Cement and Concrete manufacturing

Lime

Clay

Iron

Kiln

Gypsum

Clinker

Additions

Mill

Gravel

Cement

Admixtures

Sand

Water

Mixer



Replacement of clinker

0%

10%

20%

30%

40%

50%

60%

1999 2000 2001 2002 2003 2004 2005 2006

CEM I

CEM II

CEM III

CEM IV

CEM V


Cradle-to-Cradle Concept for Building Materials

Ensure optimal recycability of concrete

Positive list of concrete constituents

Develop new recycling technologies

Valorization of wastes and by-products from other industries

Turn the footprint positive / Eco-Effectiveness



Cradle-to-Cradle Products Develop products with positive environmental contribution


Air-cleaning concrete Fine dust reducing concrete

Documents

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