Calcination of green high-belite sulphoaluminate cement (GHSC) and performance optimizations of GHSC-based foamed concrete

Abstract

Green high-belite sulphoaluminate cement (GHSC) was firstly calcined by whole industrial wastes. Foam and GHSC-based foamed concrete (GHSFC) were subsequently investigated by orthogonal test with three types of foaming agents (plant protein PPF, animal protein APF, and polymer compound PCF), dilution ratios and valve angles of foaming machine suction (α). The foam density (ρF), foam multiple (βF), 1 h settling distance (SD) and 1 h bleeding volume (BV) of preformed foam and the dry density (ρd), compressive strength (fcu), specific strength (fSS), thermal conductivity (kc), porosity (ε) and volumetric water absorption rate (γV) of cured GHSFC were correspondingly characterized along with microstructures and crystalline structures. The cost-effective GHSC is successfully sintered with waste desulfurized petroleum coke, mine tailings, bauxite and carbide slag with a mass ratio of 1.65:1:0.4:2.5, which possesses close minerals and cured strength to HSC through microstructure, crystallinity, and mechanical property verification. Orthogonal range and variance analysis reveal that, the PPF is the most suitable foaming agent with a dilution ratio of 1:30 and a of 60° to produce GHSFC-based prefabricated thermal insulation panels with optimal performances of ρd, fcu, fSS, kc, ε and γV being 295 kg/m3, 0.53 MPa, 1796.6 N·m/kg, 0.0785 W/m·k, 85.8% and 55.2%, respectively. Keywords: Foamed concrete, Green high-belite sulphoaluminate cement, Foaming agent, Orthogonal test, Foam property, Physical performance