Experimental Study On Preparation Of Foamed Ceramic Materials By Using Vanadium-Titanium Magnetite Tailings And Its Properties

China has a very large reserves of vanadium-titanium magnetite tailings,which will bring great pressure to the local economy and environment.With the promotion of the concept of no waste city,the recycling of vanadium-titanium magnetite tailings utilization is an urgent problem to be solved.In this paper,light-weight water-retaining bricks were prepared from vanadium-titanium magnetite tailings and waste glass.Light-weight partition plates were prepared from vanadium-titanium magnetite tailings,feldspar,silica and kaolin.The volume density,compressive strength,volumetric water absorption and pore diameter of the samples were measured by experiment.The microscopic morphology of the sample was observed by field emission scanning electron microscope.The phase composition of the sample was analyzed by XRD.The thermodynamic software HSC were used to calculate the Gibbs free energy of the foaming agent and FactSage were used to calculate the high temperature melt viscosity.The vanadium-titanium magnetite tailings are complex in compositions,mainly including ilmemite,magnetite,feldspar,diopside and other minerals.The vanadium-titanium magnetite tailings were analyzed using a differential thermal-thermogravimetric analyzer.The melting point of the tailings was around 1210?.The vanadium-titanium magnetite tailings alone cannot achieve the foaming effect,the ingredients should be regulated during the batching process.Thermodynamic calculation of the foaming agent by thermodynamic software showed that the Gibbs free energy of the 6 groups of chemical reactions were negative,indicating that silicon carbide has spontaneous reaction ability.silicon carbide is a high-temperature foaming agent suitable for foaming above 1000?.The light-weight water-retaining bricks were prepared using vanadium-titanium magnetite tailings and waste glass.the effects of tailings dosage,blowing agent dosage,foam stabilizer dosage,silica dosage,firing temperature and holding time on material properties were investigated.Comprehensive analysis when the vanadium-titanium magnetite tailings addition amount is 50wt%,the waste glass addition amount is 50wt%,the auxiliary material SiO2 addition amount is 3wt%,the blowing agent silicon carbide is 0.3wt%,the foam stabilizer sodium phosphate is 3wt%,The dispersant triammonium phosphate is 0.5wt%,the firing temperature is 1040?,the holding time is 15min,and the material properties are relatively optimal.Under this condition,the bulk density of the material is 0.26g/cm3,the water absorption rate is 56.5%,the compressive strength is 0.68MPa,and the pore size is 0.32cm.At this time,the main phase of the sample is mainly wollastonite,feldspar,diopside and iron titanium oxide.Foam ceramic partition plates were prepared using vanadium-titanium magnetite tailings,in which the amount of tailings,the amount of blowing agent,the amount of fluxing agent and the holding time were investigated.When the vanadium-titanium magnetite tailings addition amount is 65wt%,the feldspar addition amount is 20wt%,the SiO2 addition amount is 10wt%,the kaolin addition amount is 5%,the blowing agent silicon carbide is 0.1 wt%,the foam stabilizer sodium phosphate is 3wt%,the flux of sodium tetraborate is 3wt%,the dispersant triammonium phosphate is 0.5wt%,the firing temperature is 1130?,the holding time is 60min,the material properties are relatively optimal.Under this condition,the bulk density of the material is 0.59g/cm3,the water absorption rate is 2.45%,the compressive strength is 3.88MPa,and the pore size is 0.26cm,which all.meet the national standard GB/T23451-2009 construction.the main phases of the sample are diopside,feldspar,wollastonite,iron titanium oxide,hematite,magnetite.