Research On Preparation Of Porous Glass-ceramic With Smelting Slag

Porous glass-ceramic was prepared by using the smelting slag as raw material.The effects of different contents of the smelting slag,the introduced amount of activated carbon before melting pretreatment,and different foaming temperature on the preparation of porous glass-ceramic were studied.The bulk density?compressive strength?water absorption and porosity of the samples were measured in the process of the experiment.The phase structure and microstructure of the samples were characterized by X-ray diffraction and scanning electron microscope.The formulation of porous glass-ceramic was designed by using the smelting slag as the main raw material.Thermodynamic analysis of the molten water quenched slag with different content of smelting slag was carried out by DSC differential thermal analyzer,and TOM-AC thermal table analyzer was used to observe the morphological changes of molten water quenched slag billet with different smelting slag contents in the process of its gradually rising temperature,then the heating system of the sample was determined as follows:heating rate of 5?/min,foaming temperature of 1080?,the foaming time was 30 minutes,and then the sample was naturally cooled after the foaming was completed.In the case of determining the heating system,the molten water quenched slag of the different amount of smelting slag was sintered and foamed in the sintering furnace.The degree of expansion and comprehensive physical properties of the sample with40%of the smelting slag were better than those of other samples,the bulk density,compressive strength,and water absorption were 0.94 g/cm~3?16.82 MPa,and 0.75%respectively.there were two kinds of crystal phases in the sample,albite and diopside phases.Under the condition of continuously raising the foaming temperature,when the introduced amount of the smelting slag was 40%,and the introduced amount of activated carbon was 5%,the bulk density of the samples were lowered from 0.63g/cm~3 to 0.46 g/cm~3,the compressive strength decreased from 8.78MPa to 3.90MPa,the water absorption rate increased from 1.91%to 6.07%,and the porosity rate increased from 60%to 70%.The bulk density,the compressive strength,the water absorption rate and the porosity rate of porous glass-ceramic obtained by foaming at1100?were 0.60 g/cm~3?8.19 MPa?2.47%,and 63%respectively,so its comprehensive performance was better and the inquired energy-consumption was relatively low.Samples prepared at different foaming temperatures with molten water slag of different activated carbon amounts contained two crystal phases of calcium feldspar and magnesite spinel.The porous glass-ceramic samples prepared by high-temperature melting pretreatment ingredients have the advantages of uniform pore size,moderate foaming degree,low density,high comprehensive strength,low water absorption rate,high chemical stability and so on.It can be used as a light insulation material in the field of building thermal insulation,building exterior decoration and refrigerated transportation.The preparation of porous glass-ceramics from the smelting slag not only has economic value,but also protects the ecological environment.