钢渣改性用于烟气脱硫研究进展

Research progress on flue gas desulfurization by modification of steel slag

钢渣结构上疏松多孔、组分上富含氧化钙、氧化镁等碱性氧化物,因此其在溶液中碱性较高,酸中和能力强,能有效去除烟气中二氧化硫实现有效脱硫。目前钢渣主要用于湿法脱硫工艺,基本机理是气液两相间的传质过程,包括二氧化硫由气相进入液相、液相中钢渣碱性物质溶解析出、进入液相的二氧化硫与钢渣中碱性物质发生化学反应3个过程,但脱硫效果主要受前两个过程影响,主要影响因素包括入口二氧化硫质量浓度、液气比、浆液pH、反应温度、钢渣粒径等。但目前对钢渣中除氧化钙、氧化镁外其他组分对脱硫效果的影响机理研究还不够深入。因此,下一步要积极探索钢渣中不同化学组分在烟气脱硫过程中的协同作用和机理,完善钢渣用于烟气脱硫的理论基础,进而实现钢渣脱硫的工业化应用。

Steel slag has the structural characteristics of loose and porous,and rich in alkaline oxides such as CaO and MgO,so it is highly alkaline in the solution and has strong acid neutralization ability,which can effectively remove sulfur dioxide from flue gas and realize effective desulfurization.At present,steel slag-based desulfurization absorption materials are mainly used in wet desulfurization processes.The basic mechanism is the mass transfer between the gas phase and the liquid phase,which contains three steps:1)SO_(2) enters the liquid phase from the gas phase;2)the alkaline substance is dissolved out of steel slag,and 3)chemical reaction occurs between SO_(2) and alkaline substances in the liquid phase.However,the overall desulfurization efficiency is mainly affected by the first two steps.The main factors include inlet SO_(2) mass concentration,liquid-gas ratio,slurry pH,reaction temperature,steel slag particle size and so on.However,at present,the research on the influence mechanism of other components in steel slag except CaO and MgO on the desulfurization effect is not enough.Therefore,it is necessary to actively explore the synergistic mechanism of different chemical components in steel slag in the desulfurization absorption process,consolidate the theoretical basis of steel slag for flue gas desulfurization and then realize the industrial application of steel slag desulfurization.