| Abstract: | The experiments on the cemented backfilling performance of yellow phosphorus slag, including physical-mechanical properties,
chemical compositions, optimized proportion, and cementation mechanisms, were carried out to make good use of yellow phosphorus
slag as well as tackle with environment problems, safety problems, geological hazards, and high-cost issues during mining
in Kaiyang Phosphorus Mine Group, Guizhou. The results show that yellow phosphorus slag can be used as the cement substitute
for potential coagulation property. Quicklime, hydrated lime, and other alkaline substances can eliminate the high residual
phosphorus to improve the initial strength of backfilling body. The recommended proportions (mass ratio) are 1:1 (yellow phosphorus
slag:phosphorous gypsum), 1:4:10 (Portland cement: yellow phosphorus slag:phosphorous gypsum), and 1:4:10 (ultrafine powder:yellow
phosphorus slag:phosphorous gypsum) with 5wt% of hydrated lime addition, 60wt% of solid materials, no fly ash addition, and
good rheological properties. The hydration reaction involves hydration stage, solidifying stage, and strength stage with Ca(OH)2
as the activating agent. The reaction rates of yellow phosphorus slag, Portland cement, and ultrafine powder hydration with
the increase of microstructure stability and initial strength. |
