ALTERNATIVE FUEL and RAW MATERIALS
Waste that meets the acceptance criteria is used in the cement sector as a replacement for such primary fuels as coal, petroleum coke and lignite, and for such primary raw materials as limestone, clay and shale. The calorific content of the organic or material content of the mineral part of waste, which is used as an alternative fuel or an alternative raw material, is recovered in the kilns of cement factories. The use of waste as an alternative fuel in cement kilns has been described by the European Court of Justice as recycling rather than incineration.
In cement production, the following materials are used together, depending on their inherent properties:
• Alternative fuels with calorific value (waste oils, refuse-derived fuels, solvents, contaminated waste, etc.)
• Alternative raw materials with a mineral constituents suitable for clinker or cement production (ceramic waste, foundry sand, contaminated soil, etc.)
• Waste with both calorific value and mineral constituents (domestic sewage sludge, paper sludge, end-of-life tires, etc.)
• Alternative additives are fed into a cement grinding system together with clinker to produce various types of cement (blast furnace slag, fly ash, synthetic gypsum, etc.)
Position of the Turkish Cement Sector
The need for mining has dwindled as a result of the use of alternative fuels and alternative raw materials for cement production, and the reduced use of primary fossil fuels (coal, petroleum coke, lignite, etc.) and natural raw materials (limestone, marl, clay, etc.). It has thus become possible to reduce the environmental footprint of a facility through the use of alternative fuels and raw materials.
The primary approach to the reduction of greenhouse gas emissions in a circular economy should involve an increase in the use of waste with calorific value instead of fossil fuels. Since biomass in waste is considered carbon neutral, it is important that the waste used has biomass content. The CO2 emissions pf the cement sector will be reduced as a result of the use of alternative fuels with biomass content instead of fossil fuels. The biomass-containing waste used in the cement sector includes the following: waste from agriculture and forestry, dehydrated domestic sewage sludge, textile waste, end-of-life tires and fuels produced from domestic solid waste. Position of the Turkish Cement Sector Cement factories in Türkiye are spread across the entire country, and approximately 35 of 55 factories hold licenses permitting the use of waste as alternative fuel. The alternative fuels used in our country amounted to 88,000 tons in 2008, but reached 1.5 million tons in 2022. This figure corresponds to a 10% thermal substitution rate. In EU countries, around 50% of the thermal power (in some facilities, up to 100%) is generated from waste.
The use of waste as an additional fuel leads cement factories to incur the following additional costs:
• Additional investments (for feeding, storage, shipping)
• Additional production costs (production losses, increase in specific heat demand, additional maintenance costs, additional personnel, occupational health and safety measures, additional laboratories and measurements)
• Technical risks (fire, explosion)
The alternative fuels that were most widely used in the cement sector in 2022 were:
• End-of-Life Tires
• Combustible waste (Fuels derived from waste)
• Other waste containing hazardous substances resulting from the mechanical treatment of waste (including mixed materials)
• Sludge from the treatment of urban wastewater
Potential for Municipal Waste Usage
In our country, the pre-treatment of municipal solid waste for use as an alternative fuel in the cement sector is vital if the rate of alternative fuel usage is to be increased to an appropriate level, as is the case in Europe and the rest of the world.
Position of the Turkish Cement Sector
“Refuse-derived fuel” is produced from the processing of municipal solid waste in pre-processing facilities using biological drying systems installed at municipal landfills. Such facilities may be established by municipalities or private subsidiaries. Revenues are derived from the sale of recycled materials. Non-recyclable materials such as plastic, paper, cardboard, textiles and organic content are dried and used as an alternative fuel in the cement sector. The Turkish cement sector has the potential to use all of the alternative fuels that can be produced from domestic solid waste generated in Türkiye.
The use of such fuels brings the following advantages:
• Elimination of the need to import petroleum coke and coal, providing savings related to foreign exchange rates and a reduction in the current account deficit;
• Reduced greenhouse gas emissions;
• Reduction of waste sent to municipal landfills;
• Reduction in the cost municipality landfill operations.
Municipalities take advantage of YEKDEM incentives to generate electricity from waste. The cement sector in Europe reduces both its fuel costs and its greenhouse gas emissions by using recycled solid fuel containing biomass, and gains advantages from emissions trading.
TÜRKÇİMENTO continues with its awareness raising/dissemination efforts regarding the use of municipal waste when making presentations and holding talks on the determination of bottlenecks, legislation and potential solutions.
Alternative Raw Materials
Alternative raw materials that can be used in the cement sector include mine waste containing constituents such as CaO, SiO2 and Fe2O3, as well as construction waste and waste generated as a result of different industrial processes. These types of waste may include such materials as fly ash, blast furnace slag, foundry sand, and marble and gypsum waste, and can be used as an alternative raw material in the cement sector as a substitute for primary raw materials. Thus, the use of primary raw materials is reduced. This issue is of key importance in reducing the use of natural resources.
The alternative fuels widely used in the cement sector in 2022 were:
• Volatile Coal Ash
• Waste sandblasting materials other than 12 01 16
• Slag processing waste
• Bottom ash, slag and boiler dust
• Waste Concrete and Concrete Sludge
Contribution to the Circular Economy
A large amount of waste is generated in the "Linear Economy" model based on the "Buy, Build and Discard" principle, which assumes that resources are plentiful and accessible and that the disposal of waste is cheap. The model also con tributes to environmental degradation and climate change, the rapid consumption of natural resources, and an increased need for imported raw materials and fuel. The limited natural resources and the need to protect the environment and reduce waste generation highlight the need to adopt a "Circular Economy" model, which is more environmentally and economically sustainable.
Position of the Turkish Cement Sector
TÜRKÇİMENTO has published a paper on “The Role of the Cement Sector in the Circular Economy.” The cement sector is unique in terms of its inherent recycling and recovery processes. Cement production is, therefore, pivoted on the principles of the circular economy. Energy recovery and material recycling are all part of the production phase, including:
• The use of waste as additional fuel
• The treatment and use of municipal solid waste and sludge as fuel
• The use of fly ash and slag as a raw material
• The utilization of waste as an alternative raw material
Last Updated: 3 July 2023