新疆准东地区煤炭资源储量丰富、易开采，但准东煤中高含量碱金属Na导致其在燃烧过程中会出现严重的沾污结渣问题，严重限制了准东煤的大规模利用。准东煤开采利用中会产出大量煤矸石，若能将其与准东煤结合利用，不仅能解决部分煤矸石堆积占地和污染的问题，也有助于实现准东煤的清洁高效利用。针对准东高碱煤沾污结渣问题，综合运用TGA-DSC、XRD、XRF等分析手段研究了温度和煤种对Na释放特性的影响以及煤矸石添加剂的捕钠效果。结果表明：准东煤500 ℃灰化灰Na释放量随温度升高而增加，最大的2个温度区间为500～850 ℃（红沙泉Na释放量:24.62%,西黑山Na释放量:22.30%）和1 200～1 400 ℃（红沙泉Na释放量:20.37%,西黑山Na释放量:49.09%）；红沙泉掺混样品在850和1 000 ℃的Na保持率相对原样分别提升22.60%和19.23%，以K(Na,K)3Al4Si4O16和NaAlSi3O8形式将Na固留在灰中；西黑山掺混样品在850和975 ℃的Na保持率相较原样约提升15%，以NaAlSiO4和Na6(AlSiO4)6形式固定Na；1 200 ℃以上，2组样品中的Na均以非定形态物质存在；Na的捕获与释放同时进行，煤矸石添加剂捕获的Na含量随温度升高而下降，但在高温1 400 ℃下，2种准东煤掺混样品的Na含量均为原样的2倍以上，仍具有较好捕钠效果。

The coal resources in Zhundong area of Xinjiang is rich and easy to exploit. However, the high content of alkali metal (sodium) in Zhundong coal leads to serious fouling and slagging during combustion, which seriously restricts the large-scale utilization of zhundong coal. A large number of coal gangue will be produced in the mining and utilization of Zhundong coal. If it can be combined with Zhundong coal, it can not only solve the problems of coal gangue accumulation, occupation and pollution, but also make new contributions to the clean and safe utilization of Zhundong coal. Aiming at the fouling and slagging problems of Zhundong high-alkali coal, the effects of temperature and coal type on sodium release characteristics and the sodium capture effect of coal gangue additives were studied by comprehensively using TGA-DSC, XRD, XRF and other analytical methods. The results show that the amount of sodium released from ashed Zhundong coal at 500 ℃ increases with the rise of temperature. The two largest temperature ranges are 500-850 ℃(HSQ:24.62%,XHS:22.30%) and 1 200-1 400 ℃(HSQ:20.37%,XHS:49.09%). The sodium retention rate of HSQ blended sample at 850 ℃and 1 000 ℃ are increased by 22.60% and 19.23%, respectively, and sodium is immobilized in the ash in the form of K(Na,K)3Al4Si4O16 and NaAlSi3O8. The sodium retention rate of XHS blended sample at 850 ℃ and 975 ℃ is increased by about 15% relative to the original, and NaAlSiO4 and Na6(AlSiO4)6 are the main forms of sodium. Above 1 200 ℃, the Na in the two groups of samples is present as amorphous substances. The capture and release of sodium are carried out simultaneously, and the sodium content captured by coal gangue additives decreases with the increase of temperature, but at a high temperature of 1 400 ℃, the sodium content of the two Zhundong coal blended samples is more than twice that of the original sample, and still has a good sodium capture effect.

0 引言

1 试验

   1.1 试验样品

   1.2 矿物转化特征温度测定

   1.3 Na迁移特性试验

2 结果及讨论

   2.1 准东煤掺混煤矸石灰样的TGA-DSC分析

   2.2 XRD物相分析

   2.3 微观形貌和组分

   2.4 Na保持率

3 结论