Properties and microstructure of total tailings cemented paste backfill material containing mining and metallurgical solid waste

Introduction: In order to improve the utilization efficiency of industrial waste discharged in process iron and steel metallurgy, a kind material that can replace cement for mine filling is sought. test, slag (SS) vanadium-titanium (VTS) were used as primary raw materials prepare cementing agents (CA). Then, combine it with ore tailings (VTIOTs) make cemented paste backfill (CPBM). Methods: The composition, properties hydration mechanism CPBM are studied through various tests, in-cluding mechanical property heat X-ray diffraction (XRD), scanning electronic mi-croscopy (SEM), fourier transform-infrared spectroscopy (FT-IR). Results: results show when following conditions met, slump 216 mm, 28-day flexural strength compressive reach 4.25 9.41 MPa, respectively, which meets requirements Chinese National Standard GB/T 39489-2020 Technical specification total backfill: mass percentage SS: VTS: phosphogypsum (PG): dicyandiamide (DWS) = 31:59:6:4; content compound phosphoric acid (CPA) accounts 4% dry material; sand ratio 1:4; concentration (PMC) 80%; water reducing agent (WRA) 0.18%. Discussion: Mechanism studies product CA mainly ettringite (AFt) C-S-H gel. addition CPA promotes active minerals SS VTS. existence PG pro-motes formation AFt, AFt further fracture [AlO 4 ] 5− [SiO 4− along bridge oxygen VTS SS.