钙基催化木屑煤混燃及其对排放、灰分特性的影响

以木屑和褐煤为研究对象,利用循环流化床反应装置,研究了不同燃烧工况下钙基对SO2、NOx排放特性的影响;并通过X射线荧光光谱仪(XRF)、X射线衍射仪(XRD)和等离子体原子发射光谱仪(ICP)测定了底灰的元素、基团和矿物组成,对附加碱金属Ca的灰样进行了熔融特性分析。研究表明,钙基对SO2、NOx的释放有一定的抑制作用。当过量空气系数α为1.0时,石灰石的添加对NOx减排最为明显。且随着木屑含量的减少,NOx产率有所降低;钙基对SO2的脱除受反应温度的影响。在温度为700～900℃、Ca和S质量比为2.0时的固硫脱硫效果最好;在CaCO3的作用下,底灰的熔融现象基本消失。

Effect of Calcium Salt Catalysis on Ash and NOx/SO2 Emission Characteristic during Co-combustion

Choosing lignite mixing with sawdust as object,the effect of calcium salt catalysis on SO2 and NOx emission was analyzed by using circulating fluidized bed reactor.The ash elements groups and mineral composition of ash samples were measured through X-ray fluorescence spectrometer(XRF),X-ray diffraction(XRD) and inductively coupled plasma atomic emission spectrometer(ICP).The result showed CaCO3 had a certain effect on SO2 and NOx emission reduction.The addition of limestone had obvious effect on NOx emission reduction with α=1.0.NOx production reduced with the decreasing of sawdust content.The removal of SO2 was controlled by reaction temperature.Under the condition of temperature of 700～900℃ and Ca/S of 2.0,desulfurization was the best.The ash melting phenomenon disappeared with the effect of CaCO3.