脱硫添加剂催化煤燃烧的动力学及机理

Kinetics & mechanism of desulphurization additive on the catalysis of coal combustion

实验研究了CaO脱硫添加剂对煤燃烧的影响,分析了燃烧后的烟气成分和煤灰特性。通过机理函数的计算,得出了燃烧反应动力学参数。实验结果表明,添加剂TiO2对CaO脱硫和煤燃烧有明显的催化作用,通过活性表面增加氧的吸附作用,疏松煤灰结构;它的dsp杂化轨道,削弱C与H,O等元素之间的化学键,促进C-C键的断裂,以获得更多的小分子量的气体,促进煤的挥发分析出,催化煤完全燃烧;计算结果表明降低了燃烧反应活化能,与实验结果吻合很好。

The effects of TiO2 on the CaO desulphurization and coal combustion were investigated.The flue gas components and coal ash characters were analyzed.The kinetics parameters such as reaction order and activation energy were calculated by analyzing the mechanism functions.The results show that the coal combustion efficiency and coal desulphurization can be effectively improved by TiO2 addition.Because of the active centers of nano-TiO2 surface,this is helpful to the diffusion of O2,reaction of SO2 with CaO.TiO2 is a catalyst to the coal combustion due to its transition metal oxide character;it can weaken the C,H and O bond and accelerate the C-C bond breaking through its dsp orbit,therefore the small molecular gases were produced,many grooves on the surface of the coal particles are formed.Finally,the accelerating effects of TiO2 on the burning of the coal are observed.The calculation results show that TiO2 reduced the combustion reaction apparent activation energy and agree with the experimental results.