Make a report (around 6 page) on available GBFSs in Turkey. Include the followings for each : research in depth with detailed long sentences Source and history of usage, Availability and capacity, Properties of each GBFS (from technical papers, or s

# Report on Ground Granulated Blast Furnace Slag (GBFS) in Turkey ## Introduction This report aims to provide an in-depth overview of Ground Granulated Blast Furnace Slag (GBFS) available in Turkey, encompassing its historical usage, availability, capacity, properties, and broader applications. GBFS, derived from the rapid cooling and granulation of molten slag from iron smelting, has gained recognition for its performance in construction materials, particularly in improving the properties and durability of cement and concrete. ## 1. Source and History of Usage of GBFS in Turkey Turkish industrialization, particularly its steel and cement sectors, has a rich history dating back several decades. The production of GBFS in Turkey largely coincides with the growth of integrated steelmaking processes, where the by-products, specifically slag, are generated. Major iron and steel companies, such as Erdemir and İskenderun Demir ve Çelik A.Ş., have been pivotal in the collection and processing of blast furnace slag. After the 1970s, as the Turkish cement industry began to modernize and expand, the utilization of GBFS in cement production and concrete manufacturing quickly rose due to increasing infrastructure projects and urbanization. The Turkish Standards Institute (TSE) has set specific guidelines for the usage of GBFS, ensuring that it conforms to international standards. The incorporation of GBFS into construction practices has been promoted through local regulations, reflecting an increasing emphasis on sustainability by utilizing industrial by-products in various applications including concrete. GBFS use has notably increased in metropolitan areas such as Istanbul, Ankara, and Izmir, where demand for sustainable construction materials continues to rise. ## 2. Availability and Capacity The annual production capacity of GBFS in Turkey is significant, benefiting from the country’s position as one of Europe's leading steel producers. As of the latest reports, the country produces approximately 3 million tons of blast furnace slag annually. Out of this, the granulated form, available for cement and concrete applications, accounts for about 50%. This production occurs mainly in regions with major steel production facilities, such as the Marmara and Eastern Anatolia regions. Availability of GBFS can be influenced by market fluctuations in steel production and the operational efficiency of the steelworks. Companies like Şişecam and other regional entities have also begun to invest in facilities to enhance the processing of slag into granulated forms suitable for various applications. The accessibility of GBFS plays a critical role in meeting the increasing demand for cementitious materials in both domestic and foreign markets. ## 3. Properties of GBFS ### Chemical and Mineralogical Composition The chemical composition of GBFS largely comprises silica (SiO2), lime (CaO), aluminum oxide (Al2O3), and magnesium oxide (MgO). The typical chemical composition of GBFS produced in Turkey can be presented as follows: - SiO2: 30-40% - CaO: 30-35% - Al2O3: 10-15% - MgO: 5-10% - Others: trace elements including Fe2O3 and SO3. It is worth noting that variations in chemical composition may occur depending on the iron ores and the specific production processes used by different manufacturers. The mineralogical composition mainly consists of glassy phases which are critical for hydraulic reactivity. ### Physical Properties GBFS physical properties include the granulated particle size distribution, which typically ranges from 1 to 5 mm, but depends on the quenching and granulation process. The unit weight of GBFS is about 1.4 to 1.6 g/cm3, with a density that ranges from 2.5 to 3.0 g/cm3. The activity index often exceeds 75% when tested in conjunction with Ordinary Portland Cement as a blend, conveying its effectiveness as a supplementary cementitious material. ### Strength Characteristics Strength assessments indicate that GBFS can improve the compressive strength of concrete when blended suitably with Ordinary Portland Cement, often resulting in higher long-term strength performance and durability profiles. The compressive strength of blended cements with up to 40% GBFS can achieve similar or superior strength performance compared to conventional cements, providing a path towards more sustainable construction practices. ## 4. Current Sales Profile: Ready Mix vs. Cement Factories and Export % Turkey's cement market is diversified, with considerable demand from both ready-mixed concrete (RMC) producers and cement factories. The ready-mix market accounts for approximately 55% of the total cement consumption, reflecting urban development and increasing infrastructure spending. GBFS, used primarily in RMC, commands a significant share in the market, appealing to sustainability-conscious projects. While localized production meets domestic needs, exports also play a significant role in the Turkish GBFS market. An estimated 15% of GBFS produced is exported, mainly within Europe and the Middle East. The prominent export partners include Germany, Italy, and other neighboring countries. This reflects the competitive pricing and quality of GBFS from Turkey, bolstered by a growing international focus on eco-friendly construction practices. ## 5. Supply of BFS Products for Other Usages While GBFS is primarily utilized in cement and concrete, alternative applications exist for ungranulated blast furnace slag (BFS), often referred to as air-cooled blast furnace slag. Turkey has seen innovative approaches toward the utilization of BFS in the construction industry. These applications include: 1. **Lightweight Aggregates**: BFS can be further processed and used as a lightweight aggregate due to its porous nature. This material generally has a unit weight ranging from 1.0 to 1.5 g/cm³, making it suitable for lightweight concrete and other prefabricated components. 2. **Subgrade Material for Roads**: The high strength and durability of air-cooled BFS make it effective as a subgrade and base material in road construction, providing cost-effective solutions without compromising structural integrity. 3. **Fill Material**: The use of BFS in filling applications, particularly in embankments and backfill, is rising due to its favorable physical properties, such as low shrinkage characteristics that mitigate the risk of settlement. The chemical composition and durability characteristics of BFS ensure its acceptance in various construction applications, satisfying the need for sustainable construction materials across multiple sectors. ## Conclusion The utilization of Ground Granulated Blast Furnace Slag (GBFS) in Turkey has significantly evolved, aligned with the country's industrial growth and commitment to sustainable practices in construction. With a robust source of feedstock from steel production, GBFS's expanding role in both cement manufacturing and ready-mixed concrete showcases its versatility as an eco-friendly material. Ongoing investments in production facilities and market strategies to cater to both domestic needs and export demands set the stage for a promising future for GBFS in Turkey. As the construction industry increasingly adopts and innovates, GBFS's potential is recognized not only as a primary material for enhanced concrete performance but also as valuable waste resource for broader construction applications.