İremnur CEYLAN, M. Sc. Student

Metallurgical and Materials Engineering

Yıldız Technical University

 

irmnrcyln@gmail.com

www.linkedin.com/in/iremnurceylan/

 

Blast Furnace Slag-derived Sustainable Glass-Ceramic Coatings Application

Supervisor: Assoc Prof. Dr. Buğra Çiçek

Glass-ceramic coatings obtained by vitrification and recrystallization of oxides such as SiO2, B2O3, Al2O3, Na2O, NiO, CuO, P2O5, Fe2O3 in accordance with the Seger formulation are semi-crystalline glassy coating materials [1]. Blast furnace slag (BFS) that the most common industrial waste was implemented as raw materials in glass-ceramic coating formulation by drying at 320 °C and pulverizing about 30 mins. The chemical composition of BFS consists of 35-42% CaO, 35-40% SiO2, 8-15% Al2O3 and 5-9% MgO as the main components [2]. This study aims to provide a further strategy for developing sustainable glass-ceramic coating by combining BFS waste (as a source of CaO, SiO2 and Al2O3) with commercial raw materials via melting of batches and quenching of melts. F-STD and F-BFS frits were produced at 1250 °C for 1 h by 100% commercial raw materials and partially BFS added, respectively. Characterization of frits were conducted in terms of chemical composition (XRF), phase transformation (XRD), and thermal behavior (Heating Microscopy and Dilatometry). The frits were milled in 300 g batches with a total weight of 750 g alumina balls with a diameter of 1-1.5 cm and 1 ml silicone oil in a 300 RPM mill for 30 mins. After electrostatic application of frits on DC01EK (EN10027–1) steel plate and devitrification process at 830 °C for 4.5 mins, glass-ceramic coatings that has sample nomenclatures as GC-STD and GC-BFS were obtained. GC-STD and GC-BFS coatings were characterized in terms of micro and macro-structure, chemical composition (XRF), phase formation (XRD), surface morphology (SEM), adhesion (BS EN 10209), acid resistance (EN ISO 28706-1), aesthetic properties (glossmeter and spectrophotometer). After characterizations, it was proved that the use of BFS instead of commercial raw materials does not adversely affect the engineering and aesthetic properties of the glass-ceramic coatings and BFS can be a successful sustainable raw material for coatings.

 

[1] A. I. Andrews, S. Pagliuca and W. D. Faust, Porcelain (Vitreous) Enamels - Industrial Enamelling Processes, Mantova: International Enamellers Institue, 2011.

 

[2] M. Tokyay, "Blast furnace slag," in Cement and Concrete Mineral Admixtures, New York, CRC Press, 2016, pp. 23-28.

 

Utilization of Colemanite Enrichment Waste as Boron & Calcium Sources of Glass-Ceramic Coatings

 

The first 3 rankings in the world boron mineral deposits are in Turkey, in the US, and in Russia, with Turkey governing the world reserve of 73% boron deposits [1][2]. The state-owned Eti Mine produces 400,000 tons of various boron waste (BW) products from extraction, refining and enrichment processes each year due to its large-scale production and ore processing [2][3]. Due to the fact that the high amount of waste is boron oxide (B2O3) and calcium oxide (CaO) rich in content, the study includes the utilization of BW as alternative B2O3 and CaO raw materials rather than pentaborax (B4H10Na2O12) and calcium carbonate (CaCO3) in the glass-ceramic coating composition. BW without any heat-treated nomenclatured as BW0. BWs that pre-calcined at 300 °C and calcined at 500 °C and 900 °C nomenclatured as BW50 and BW90, respectively. BWs were characterized via XRF, XRD, TG-DTA, FT-IR and SEM. After BWs characterization, frit formulations were developed. By using 100% wt. commercial raw materials, a frit was produced nomenclatured as F-STD. In addition, frits that contains BW0, BW50 and BW90 nomenclatured as follows: F-BW0, F-BW50 and F-BW90, respectively. Chemical compositions, phase formations and crystallinity, thermal behaviors of frits were characterized with XRF, XRD, heating microscopy and dilatometer. Pre-characterized and milled F-STD, F-BW0, F-BW50 and, F-BW90 powders were applied by electrostatic spray method on (DC01EK) steel plates with 150-200 µm thickness in accordance with EN 10209 standard. After coatings, glass-ceramic coatings that nomenclature as GC-STD, GC-BW0, GC-BW50, and GC-BW90 were obtained by pre-heating at 550 °C for 4.5 min and recrystallization at 830 °C for 4.5 min. The chemical composition, crystal structure, surface morphology, chemical and mechanical resistance of glass-ceramic coatings were investigated by means of XRD, SEM, citric acid test (EN ISO 28706-1), adhesion test (BS EN 10209), respectively. This study proves that BWs can clearly be used as alternative raw materials, coating quality will be maintained, and cost will be decreased.

[1] Boron Minerals in Turkey, Their Application Areas and Importance for the Country’s Economy - Yakup Kar, Nejdet Şen, and Ayhan Demirbaş - MINERALS & ENERGY VOL 20 NOS 3–4 2006 DOI: 10.1080/14041040500504293

[2] Eti Mine Works, (n.d.) http://www.etimaden.gov.tr/ (Accessed May 10, 2020).

 

[3] European Commission, Reference Document on Best Available Techniques for Management of Tailings and Waste-Rock in Mining Activities, 2004.

 

Patent

  • Frit composition containing industrial waste developed for use in the structure of vitreous enamel coatings  (Pat. Pending)