A few cement companies in Europe have achieved 80 per cent of Total Substitution Rate (TSR) value in the usage of alternate fuels. These are the measures that Irish cement maker CRH adopts.
As a part of its sustainability initiative, CRH group has been doing excellent work in the field of alternate fuels and raw materials. Please highlight your achievements….
Alternative Raw Materials
Alternative raw materials can be used in two parts of the cement manufacturing process to reduce carbon emissions. Firstly, by replacing a portion of the raw materials with fly ash, slag, quarry overburden or other process by-products in raw meal (i.e., at the kiln input). Or secondly, by replacing a portion of clinker with ground limestone, fly ash, slag or other process by-products in the blended cement. Both of these techniques are used by CRH.
During 2015, a total of 3.8 million tonne (2014: 1.8 million tonne) of alternative materials were used in CRH?s subsidiary cement plants.
Alternative Fuels
Alternative fuels used by CRH cement plants typically include Solid Recovered Fuels (SRF), waste tyres, used oil and carbon-neutral biomass (meat and bone meal, wastewater treatment plant residue, rice husk, etc.). Alternative fuels in general have a lower carbon intensity. Substituting traditional fossil fuels with alternative fuels reduces CO2 emissions and also supports the circular economy, by reusing by-products and wastes from other industries.
In 2015, CRH?s subsidiary cement plants used 1.6 million tonne of alternative fuels (2014: 547,000 tonne). This provided 30 per cent of total energy consumption for cement activities, similar to the previous year.
What are your plans to take it forward, considering your target of 25 per cent reduction in specific net CO2 cement plant emissions by 2020 on 1990 levels?
Our CO2 cement plant emissions reduction target refers to wholly owned cement plants which were owned by CRH in 2013 when the target was set. CRH is continuously working on improving kiln efficiencies, which includes increasing the use of alternative raw materials, through optimisation of clinker mineralogy.
Some of your plants in Eastern Europe have TSR as high as 80 per cent, what kind substitute fuel is used in these places?
Thermal Substitution Rates for individual plants are not disclosed by CRH. The following types of alternative fuels are typically used: used tyres, Refuse Derived Fuels (RDF), Sold Recovered Fuels (SRF), Meat & Bone Meal (MBM), dried sewage sludge and wood.
What is the average TSR for CRH as a group? What is the way forward?
CRH does not disclose Thermal Substitution Rates for the Group. The Group?s CSI KPI for Alternative Fuels & Materials (as found on page 64 of our 2015 Sustainability Report) is percentage fuel substitution for virgin fuels which in 2015 was 33.9 per cent. CRH is continuously working on the sharing of information and best practices between operations globally to help improve kiln efficiencies.
What kind of safety standards do you observe while using industrial waste at the plants?
CRH is a member of the Cement Sustainability Initiative (CSI) Safety Task Force. CSI has published good practice guidelines on safety procedures in the cement industry which address the handling of alternative fuels. The CSI guidelines require that adequate documentation and information on safe material handling, operating procedures and easily understood safety and emergency instructions are provided to ensure the workforce is knowledgeable about hazards and safety measures put in place for worker protection.
What is the motivational factor for your plants to use more AFR in manufacturing? Specifically CRH aims to:
- Reduce absolute CO2 emissions (gross and net) and achieve CRH?s target to reduce specific net CO2 cement plant emissions by 2020,
- Within CRH, 82 per cent of total CO2 emissions arise from cement activities. Therefore, the CO2 emission reduction commitment is focused on this source.
- 25 per cent reduction in specific net CO2 cement plant emissions on 1990 levels by 2020.
The first CO2 reduction commitment was met three years ahead of schedule, in 2012. CRH is confident that it is also on target to deliver the 2020 commitment.