掺烧废弃硅粉对准东煤钠迁徙及灰熔融影响的实验研究

Experimental Research on the Impacts of Zhundong Coal Blending Waste Silicon Powder on Sodium Transformation and Ash Fusion

将废弃硅粉与准东五彩湾煤掺混燃烧,研究其对准东五彩湾煤钠迁徙及灰熔融特性的影响。实验结果表明:准东煤掺混硅粉后,灰样中的钠显著增加,固钠率随硅粉掺混比例的增加而增加;灰样的灰熔融特征温度随硅粉掺混比例的增加,呈现先降低后升高的趋势,XRD及XRF分析表明,掺混硅粉会导致准东煤灰内的CaSO4提前发生分解,分解产生的CaO容易形成低温共融的钙铁辉石,是导致准东五彩湾煤灰样熔融温度降低的主要原因,但掺混比例达到9%时,方石英成为灰样内主要成分,能够起到"骨架"作用而导致灰样熔融温度升高。

The Zhundong Wucaiwan coal is blended with the waste silicon powder and combusted to study the ash fusion and sodium transformation characteristics of the coal.The experiment resuhs show that,the sodium content of the ash increases substantially when the waste silicon powder is added to the coal.With the blending ratio of the waste silicon powder increasing,the sodium fixation rate rises accordingly.Meanwhile,the characteristic temperature of the ash tends to go up first and then down.The X-ray diffraction （XRD） and X-ray fluorescence （XRF） analyses indicate that the waste silicon powder causes the CaSO4 in the Zhundong Wucaiwan coal to decompose at lower temperatures and produce a large amount of CaO which is apt to form eutectic hedenbergite.This is the major reason for the ash fusion temperature decrease.However,when the blending ratio reaches as much as 9%,crystobolite will become the dominant component and can act as the backbone of the ash,which leads to the increase of ash fusion temperature.