CRH recognises the challenge posed by climate change and is committed to the sustainability of its business activities. In 2006, CRH made a commitment to achieve a 15% reduction on 1990 levels in specific carbon dioxide (CO2) emissions by 2015, for a defined portfolio of cement plants.
Approximately 40% of the CO2 generated in the production of cement clinker arises from the carbon content of the fuels used, due to the traditional reliance on fossil fuels within the industry. In order to reduce the carbon footprint of its process, Irish Cement has embarked on a programme of the displacement of traditional fossil fuels in its cement kilns with sustainably procured, specially prepared, waste-derived alternative fuels. The first step in this strategy has been implemented, with the substitution of a proportion of the coal used at Platin Works with prepared Solid Recovered Fuel (SRF), the primary alternative fuel used by Irish Cement due to its availability and technical compatibility.
SRF is the clean, dry blend of fragments of plastics, paper, cardboard and textiles which arise once recycling of waste materials has been completed through mechanical and biological treatment. This fuel is produced to defined chemical and physical standards suited to the cement industry. >50% of the thermal energy requirements of the clinker manufacturing process at Platin will be supplied using alternative fuels in the future.
The introduction of alternative fuels represents a fundamental change to the cement manufacturing process at Irish Cement facilities. Some of the challenges include:
• Establishing sustainable supply chain relationships for appropriately specified fuel sources
• Specifying and installing equipment and appropriate technology solutions to handle and transport the fuels on site
• Implementing testing and analysis activities required to guarantee ongoing quality control in cement production
• Managing communications with all stakeholder groups
• Reduction in carbon footprint and environmental impact.
• Improvement in business sustainability through reduced reliance on imported fossil fuels and increased security of fuel supply from indigenous sources.
Some of the many societal advantages of using alternative fuels in the cement manufacturing process are:
• Complete recovery of the energy value of the waste derived materials due to the
efficiency of the combustion process in a cement kiln
• Reduction in CO2 emissions
o Directly, due to lower carbon emissions arising from the lower carbon intensity of the fuels
o Indirectly, by diverting material from landfill thereby reducing landfill gas production
o Indirectly, by eliminating the need for dedicated incineration capacity
o The biomass fraction of the fuels is considered renewable and CO2 free
• Reduction in the dependency on imported fossil fuels
• No residual wastes are produced from the cement manufacturing process. The organic fraction contributes to the combustion process and the inorganic components are incorporated into the cement product thereby eliminating the requirement for additional landfill capacity
• Complete destruction of fuels due to high temperatures, long residence times and high thermal inertia
• Reduction in the input of raw materials and additives due to the minerals present in alternative fuels
• Contribution to Ireland’s international obligations:
o Provides the most efficient energy recovery option
o Assists in achieving national landfill diversion targets
o Assists in meeting national greenhouse gas reduction obligations