氧燃烧方式下矿物质与重金属行为特征的研究

在沉降炉试验台上,进行空气气氛及O2/CO2气氛燃煤试验,通过X射线衍射分析和ICP-AES分析研究了不同气氛下煤灰中矿物质组成及痕量元素的挥发特性.并根据热力学多相平衡原理对矿物质与重金属在两种气氛下的挥发行为进行了计算和比较分析.结果表明,氧燃烧气氛下的矿物质组成与空气气氛下并无明显不同,矿物质元素的蒸发气化亦没有受到明显的影响,但在氧燃烧气氛下矿物质的晶相向非晶相的转化得到了较大改善,有可能使电站锅炉沉积得到缓解;氧燃烧气氛下灰中痕量元素相比空气气氛下在底灰中有明显的富集.

THE STUDIES OF THE TRANSFORMATION OF MINERAL AND HEAVY METALS UNDER THE OXY-COAL COMBUSTION WAY

Coal combustion is investigated under the atmospheres of both O_2/CO_2 combustion way and Air combustion way,which is operated trough the drop-tube furnace.Use XRD and ICP-AES methods to analyze the components of minerals and the Trace elements' vaporization characteristics. According to thermodynamic Multi-phase equilibrium theory,the vaporization behavior of mineral and Trace elements is calculated and compared between two atmospheres.The experimental results show that the mineral composition and the evaporation isn't obviously changed,but the transformation of crystal phase to non-crystal phase is inhibited,which would ease the deposition of the boiler of power station;it shows greater enrichment of trace elements in bottom ash under oxy-coal combustion condition.