Thermal and mechanical properties of coal gasification slag based foam concrete

Abstract

Foam concrete possesses low density and excellent thermal insulation properties and has been widely used in construction industry. Considering the recycling and reusing of coal gasification slag (CGS), a solid waste product in the coal chemical industry, CGS was used as the supplementary cementations material to prepare foam concrete (CGS-FC) in this work. The influence of the CGS content and water-binder ratio on the pore structure, mechanical and thermal properties was investigated. The results show that the CGS content and water-binder ratio directly impact the fluidity of the slurry, which affects the internal pore structure of the specimens after molding. And a CGS-FC with a compressive strength of 6.89 MPa, thermal conductivity of 0.24 W/m K, and a bulk density of 867 kg/m³ was successfully produced when the CGS content was 30% and water-binder ratio was 0.5. In particular, the utilization of CGS to prepare foam concrete product has recycling efficiency and environmental benefit.

Keywords: Foam concrete; Gasification slag; Lightweight building materials; Mechanical properties; Pore structure; Thermal insulation.