Study On Preparation Technology And Properties Of Glass Ceramics With Different Proportion Of Blast Furnace Slag And Flyash

Blast furnace slag is a kind of waste slag with a large amount of discharge in China's metallurgical industry.The temperature of blast furnace slag can reach more than 1400?,and each ton of slag contains heat equivalent to 60kg of standard coal.At present,blast furnace slag is mainly used to produce cement and slag powder after water quenching.There are many disadvantages in this way,such as large investment,low added value of products,and ineffective utilization of slag heat.Fly ash is a kind of industrial waste discharged by coal-fired boiler in thermal power plant.If it is discharged at will,it will pollute the environment and cause waste of resources.The chemical composition of blast furnace slag and fly ash is complementary,which is the best choice for the preparation of architectural decorative glass ceramics.Therefore,it is of great significance to carry out the basic research on the preparation of microcrystalline glass with blast furnace slag and fly ash.In this paper,the basic glass formula with pyroxene as the main crystal phase is designed.Through the calculation of factsage 7.1 software,the conditions of adding2.0wt%Cr₂O₃ and 4wt%Fe₂O₃ nucleating agent.X-ray diffraction and scanning electron microscopy were used to analyze the crystallization mineral composition and microstructure of the samples after heat treatment.The physical and chemical properties of the samples after heat treatment,such as flexural strength,density and water absorption,were determined to determine the influence of the physical and chemical properties of blast furnace slag and fly ash glass ceramics.In order to make full use of the heat energy of the blast furnace slag and reduce the energy consumption of the glass-ceramic prepared by the melting method,the heat supplement problem of the basic glass-ceramic prepared from the molten blast furnace slag was studied.Through the study of the ratio of different blast furnace slag and fly ash,it is found that the two groups of samples with“65%blast furnace slag+15%fly ash+20%quartz sand”and“70%blast furnace slag+5%fly ash+25%quartz sand”are used as the nucleation temperature and 934?resply at 777?and 941?.At 941?,the crystallites of the glass ceramics are fine,the crystal phase distribution is uniform,the crystal morphology is well developed;the highest flexural strength is 178.20mpa and178.17mpa;the highest hardness is 818HV and 812HV,respectively;the lower water absorption is 0.12%and 0.13%;the acid resistance was 99.6%and 99.9%respectively,and the alkali resistance was 99.6%and 99.8%respectively.Compared with the current research at home and abroad,the glass ceramics made by this method is in the middle and upper level.According to the thermodynamic calculation of the heat supplement problem of glass ceramics prepared by different ratio of blast furnace slag and fly ash,it is found that the heat of 479.30kJ,337.50kJ,261.90kJ,628.70kJ and 425.83kJ in addition to the physical heat brought in by the hot blast furnace slag?1400??and the chemical heat released from the combustion of the residual carbon in the cold fly ash are needed to be supplemented from the outside.The supplementary heat accounts for 32.50%,22.98%,18.21%,40.54%and 29.10%of the total heat of glass liquid respectively.It can be seen that to prepare glass ceramics will greatly reduce the energy consumption in the process of melting glass ceramics.The research results of this paper provide a feasible scheme for the recycling of two kinds of solid waste resources,blast furnace slag and fly ash,and improve the performance of blast furnace slag glass ceramics and the utilization rate of blast furnace slag,providing important reference value and guiding significance for its industrial production.