湿磨时间对钢渣泥碳化固结特性的影响机理研究

Influence Mechanism of Wet Grinding Time on Carbonization and Consolidation Characteristics of Steel Slag Mud

磁选回收铁是钢渣利用的有效方法之一,但由此产生的钢渣泥水化活性低,目前尚无有效利用手段。加速碳酸化养护技术对提高钢渣产品的早期强度和体积稳定性有积极作用,通过碳化养护方法研究了不同湿磨时间下钢渣泥碳化块体材料的抗压强度和碳酸化程度,并利用XRD和热重-差热分析阐明强度增强机制。结果表明:①钢渣泥具有碳化固结特性,其中湿磨60 min钢渣泥碳化固结特性最好,钢渣湿磨有最优的时间,过长时间粉磨不利于碳酸化固结。②钢渣泥强度与碳酸化程度成正比,在压制成型与碳化养护过程中,水化反应作用微乎其微,碳化产物的生成带来强度的提升。③钢渣在湿磨成为钢渣泥的过程中发生了水化反应,且部分水化产物容易与空气中的CO_(2)发生碳酸化反应,生成碳化产物。碳化养护可以使碳酸化反应进行得更为彻底,且碳化产物晶型更为稳定。研究成果为钢渣泥的综合利用提供参考。

Iron recover by magnetic separation method is one of the effective methods for the utilization of steel slag,but steel slag mud producted has low hydration activity and there is no feasible means of utilization at present.Accelerated carbonation curing technology has a positive effect on improving the early strength and volume stability of steel slag products.The compressive strength and carbonation degree of steel slag mud carbonated block materials under different wet grinding time were studied by carbonation curing method,and the strength enhancement mechanism was clarified by XRD and TG-DTG analysis.The results showed that:①steel slag mud has carbonation and consolidation characteristics.Among them,the carbonation and consolidation characteristics of steel slag mud are the best after wet grinding for 60 min.The steel slag wet grinding has the best time.Too long grinding is not conducive to carbonation and consolidation.②The strength of steel slag mud is proportional to the carbonation degree.During the process of pressing and carbonization curing,the hydration reaction is very small,and the formation of carbonized products brings about an increase in strength.③The steel slag undergoes a hydration reaction in the process of wet grinding into steel slag mud,and some of the hydration products are easily carbonated with CO_(2) in the air to form carbonized products.Carbonation curing can make the carbonation reaction more thorough,and the crystal form of the carbonized product is more stable.The research results provide a reference for the comprehensive utilization of steel slag mud.