Study On Preparation Of Glass-ceramics From Dephosphorization Slag Of High Phosphorus Manganese Alloy

China is rich in manganese ore resources,but in the domestic investigated manganese ore deposits,the phosphorus content of manganese ore exceeding the standard（P/Mn≤0.3%）is more than 49.6%,resulting that the phosphorus content of Mn-based alloy produced from high phosphorus manganese ore as the main raw material exceeds the standard（P/Mn≤0.5%）.Mn-based alloy is one of the important varieties of ferroalloys,which often used as deoxidizer,desulfurizer and alloy additives,and can improve the strength,hardness and other properties of steel.In order to improve the utilization rate of high phosphorus Mn-based alloy,it is necessary to conduct deep dephosphorization of high phosphorus Mn-based alloy.The traditional dephosphorization method mainly uses CaO-Ca F₂slag system for dephosphorization,but Ca F₂and the dephosphorization product Ca₃P₂in the dephosphorization slag are easy to hydrolyze and produce toxic HF and PH₃gases,which not only harm human health,but also seriously contaminate the surrounding environment.In order to avoid the above harm,this paper first uses aluminum base dephosphorization agent and non-fluorine covered slag（CaO-Al₂O₃-SiO₂-MgO）for dephosphorization,and then focuses on the method under the obtained dephosphorization slag green application.In the greening application,using the dephosphorization slag and waste glass as raw material to study on the basis of preparation of microcrystalline glass experiment,adjusting the experiments of dephosphorization slag content,types and adding quantity of nucleating agent,system of heat treatment,frequency of the mixing and temperature of one-step heat treatment,then the mechanical properties of the obtained glass-ceramics and phase composition are studied to determine the optimum composition.The main conclusions of the paper are summarized as follows:（1）The waste toxic and harmful phosphorus containing dephosphorization slag has been successfully prepared into non-toxic and harmless high-value-added glass-ceramics,whose performance is far higher than the national standard of industrial building materials.Moreover,the utilization rate of phosphorus containing dephosphorization slag can reach 100%,and there is no waste gas,waste water and waste solids produced during the preparation process.（2）Optimum process conditions for preparation of glass-ceramics by two-step heat treatment:68%dephosphorization slag,30%waste glass,2%TiO₂as nucleating agent,820℃/1 h+910℃/1.5 h,stirring frequency 10 times/h;The properties of the best glass-ceramics are as follows:volume density 2.94g/cm³,water absorption 0.01%,bending strength 126.1MPa,acid resistance 99.42%,alkali resistance 99.71%;（3）When the temperature reaches 950℃,the comprehensive performance of glass-ceramics is the best.Volume density 2.68g/cm³,water absorption 0.07%,bending strength 104.2MPa,acid resistance 98.39%,alkali resistance value 98.86%.