Proportion and Performance Optimization of Lightweight Foamed Phosphogypsum Material Based on an Orthogonal Experiment

Abstract

A lightweight foam phosphogypsum material (LFPM) was prepared by multi-factor orthogonal and optimization experiments. The effects of foam, quicklime, silica fume and cement on the mechanical and physical properties of this LFPM were studied. The orthogonal experimental results showed that the silica fume content exhibited the most significant effect on the strength of this material, and the cement content exhibited the most obvious influence on the softening coefficient. The comprehensive index analysis indicated that the LFPM with 8% foam, 3.5% quicklime, 3% silica fume and 15% cement was selected as the optimal proportion. The 28 d compressive strength and flexural strength were 3.15 and 0.97 MPa, respectively. The dry density was 809.1 kg/m3, and the 28 d softening coefficient was 0.628. The optimization experimental results showed that the strength and dry density of the sample increased first and then decreased with an increase in the foam stabilizer content. The strength and dry density increased, and water absorption decreased with increasing waterproof agent content.