| 论文简介 |
The characterization of ash properties is of benefit for better elucidating the ash-related issues during utilization of semi-coke. Nevertheless, the impact of different ashing methods on ash characteristics of semi-coke still remains unclear, along with the influence of blending various semi-cokes. In the present study, the ashes of pyrolyzed and gasified semi-cokes were prepared from two different methods, low-temperature plasma ashing at <200 degrees C and traditional muffle ashing at 815 degrees C to investigate the effects of ashing method on ash characteristics of semi-coke, which has been seldom conducted before. The low-temperature plasma oxidization could consume organic matter without destroying the initial state of mineral species in semi-coke matrix. A variety of analysis techniques including X-ray fluorescence (XRF), X-ray diffraction (XRD) and thermal analysis was performed to study ash composition, mineral phase, thermal volatility, and so on. The results show that the appearance and yield of low-temperature ash (LTA) and high-temperature ash (HTA) are highly related to the ashing approach and the category of semi-cokes. The mass fractions of most oxides contained in LTA are lower than those in HTA. The main difference of mineral phases between LTA and HTA of semi-cokes lies in the existence form of calcium. The ashing method exerts remarkable influences on thermal behaviors of pyrolyzed semi-coke ash but insignificant effect on those of gasified semi-coke. Moreover, the effects of blending pyrolyzed and gasified semi-cokes on the ash compositions and thermal behaviors are significant, while the mineral phases seem to be independent of the blending process. |
(创新港)
