Where was the cement sector in 2013
The cement industry is CO2, energy- and material-intensive. Measures to decrease energy consumption and improve resource efficiency will, de facto, reduce CO2 emissions, hence the focus on CO2 emissions. The combination of process emissions (those released when limestone is transformed into lime during the production process) and emissions from the required thermal energy meant that typical CO2 emissions for each tonne of clinker in 1990 were 912 kg. Reducing CO2 emissions takes a concerted effort on many parallel routes. However, there is no simple solution or single breakthrough technology that can reduce our emissions overnight. The right mix of technologies, investments and processes that will make a real difference needs to be identified. In order to do so, one must bear in mind what has worked in the past and where the sector is today.
REDUCTION OVER THE PAST 20 YEARS
Over the past 20 years, the European cement industry has reduced CO2 emissions per tonne of cement from 719 kg in 1990 to 660 kg in 2010 by implementing measures including:
- Replacing older wet technology kilns with far more energy-efficient dry technology kilns. Today, over 90% of the clinker produced in Europe is based on this technology.
- Improving grinding technologies, resulting in reduced power consumption and therefore reduced emissions by the power sector.
- Enhancing thermal energy consumption, leading to very high thermal energy efficiency in the clinker production process.
- Optimising and modernising existing plants by installing state-of-the-art automation, process control technology and auxiliary equipment.
- Using greater quantities of alternative fuels (a sevenfold increase since 1990), consisting of either waste material or biomass.
- Utilising waste material like contaminated soils, construction waste, ceramic moulds, foundry sand, gypsum from plasterboard, mill scale, cement kiln dust, refractory bricks and road sweepings or fly ashes as raw materials, thereby reducing the requirement for limestone and other virgin materials in the production process. This is possible due to the very high temperatures present in the kiln, destroying all incoming minerals and turning them into completely new clinker minerals.
- Substituting clinker with materials such as finely ground limestone filler material, ground naturally occurring pozzolans or reactive by-products from other industries, such as fly ash.
The efforts to reduce our CO2 emissions have been an integral part of improving the sustainability of our businesses and meeting the needs of our customers.
OUR UNIQUE CARBON PROFILE
The cement and lime industries are unique due to the fact that the majority of greenhouse gas emissions are not caused by energy use from fuel combustion, but come from the raw materials themselves. Around 60% of total CO2 emissions from clinker production are released directly from the processing of limestone. Of the remaining 40%, most originate from burning fuel in the kiln to reach the high temperatures necessary for clinker mineral formation. Indirect emissions from electrical power consumption contribute approximately 6% to overall CO2 emissions.
The data both above and in the following section are based on the “Getting the Numbers Right” (GNR) database. Key drivers of emissions and performance are also included. The database provides industry and policy makers with current performance figures to aid their analyses and decisions.
THE EUROPEAN CEMENT INDUSTRY IN THE EU27
(BASED ON 2011 DATA)1
|Absolute emissions of CO2
(excluding CO2 from power generation)
|Volume of alternative fuels used
|7.66 (25.6% of total thermal energy consumption)
|Volume of biomass used
|2.15 (8.7% of total fuels thermal energy consumption)
|Use of alternative raw materials in Portland or blended cements
|Total thermal energy consumption
(all fuel sources combined)
|Million tonnes of oil equivalent (roughly equivalent to the energy consumption of Ecuador)
|Co2 per tonne of clinker
|Kg CO2/tonne clinker
|Average thermal energy consumption
|Average electrical energy consumption