Effect of calcium carbonate on the preparation of glass ceramic foams from water-quenched titanium-bearing blast furnace slag and waste glass

ABSTRACT

Glass ceramic foams were fabricated with powder sintering technology at a low temperature (900°C), using water-quenched titanium-bearing blast furnace slag (WTS) and waste glass as the primary raw materials. Additionally, calcium carbonate, sodium borate and sodium phosphate were chosen as sintering aids to form excellent performance products. The effects of calcium carbonate additions on foaming process, crystal content, morphology and properties of the prepared samples were systematically researched. The research indicates that increasing the calcium carbonate content made the foaming process harder and the pore size got more uniform. Consequently, the compressive strength and bulk density increased, while the porosity and water absorption decreased. The homogenous porous structures and optimal comprehensive properties were achieved with 5–7 wt-% CaCO₃ addition, including a bulk density of 0.79–0.82 g cm^–3, porosity of 73.13–75.28%, water absorption of 3.29–3.75% and compressive strength of 13.13–13.85 MPa.

KEYWORDS:

• Calcium carbonate; glass ceramic foams
• blast furnace slag
• sintering

Acknowledgements

The authors acknowledge the Panzhihua Iron and Steel Company for providing the waste slag.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work has been financially supported by the Science and Technology Support Projects of Sichuan ‘Study on key technology of preparing microcrystalline foam glass from Panzhihua high titanium blast furnace slag’ (grant number 2014GZ0011), and Industry Promotion Projects of Panzhihua in China ‘The use of high-titanium blast furnace slag preparation of glass ceramic foams’ (grant number 2013CY-C-2).