Shell煤气化飞灰粘附特性影响因素探讨

针对Shell粉煤气化炉飞灰的粘附特性,利用XRF、激光粒度分析仪、SEM-EDX等仪器对采自皖北、云南矿区的两种煤在Shell气化过程中形成的飞灰样品进行了分析检测,探讨了化学成分、粒度分布、表面形貌及元素组成等因素对飞灰粘附特性的影响。结果表明,皖北煤飞灰中一些微量元素含量比云南煤飞灰含量高,颗粒直径在1-2μm范围的大颗粒数明显少于云南煤飞灰,但是飞灰的比表面积大于云南煤飞灰,这是皖北煤飞灰的粘附性比云南煤要高的主要原因;此外,飞灰颗粒为球状,表面附着小的球形颗粒,该颗粒的Ca元素含量较高,使得它们彼此容易粘连在一起,从而促进了飞灰的粘附和沉积。

Study on the Factors Influencing Fly Ash Deposition in Shell Coal Gasification Process

Two kinds of fly ash samples of coal collected in northern Anhui and Yunnan mining areas produced in Shell coal gasification process were analyzed by XRF, laser particle size analyzer, SEM-EDX. The influence of chemical composition, particle size distribution, morphology and elemental composition on fly ash deposition was studied. The results showed that some trace elements content （Ba, Zr, Ni, Pb, Co, Rb, Nb） in fly ash of coal from northern Anhui is higher than in fly ash of coal from Yunnan. The bigger particle number with diameters of 1-2μm in fly ash of coal from northern Anhui is much smaller than in fly ash of coal from Yunnan, and the fly ash specific surface area of coal from northern Anhui is bigger than from Yunnan, it＇s major reasons that deposition of fly ash of coal from northern Anhui is bigger than from Yunnan. Moreover, fly ash particles are spherical, which results in deposition of small spherical particles on them. These small particles are rich in Ca and easy deposition on each other, which promotes fly ash conglutination and deposition.