首钢股份烧结制粒熔剂和燃料结构优化研究

烧结混合料制粒性能直接影响着烧结料层的物理特性及烧结过程的经济技术指标,优化制粒对在当下环保受限条件下的烧结产能提高有着重要意义。因而针对首钢股份360m^(2)烧结机原燃料条件设计了制粒研究实验,以碱度、燃料结构和生石灰配比为变量,研究其对混合料制粒性能的影响。实验结果认为:良好的制粒性能应控制石灰石配比在6%以下,且保持石灰石有较高的细粉比例;考虑到转运和干燥过程,燃料由于较差的粘结性对混合料最终的平均粒度几乎没有影响;而生石灰有很强的粘结性,高生石灰配比能够保持较低的混合料脱粉率,但同时需要用大量水分去匹配,否则混合料制粒性能反而变差,5%以上生石灰配比时就要求水分配比大于7.5%。

Effect of a starch-based filter aid on the dewatering of fine clean coal

The dewatering of fine, flotation cleaned coals from Huaibei and Xuzhou (bituminous) and Yongcheng (anthracite) were studied. The supernatant and filter cake were examined to determine the rate and extent of flocculation and dewatering. A starch-based filter aid was used to increase flocculation and dewatering rates. The filtration constant, K, and compression index, s, of the Yongcheng slurry were measured under various conditions. A designed experiment was performed to determine optimum conditions for dewatering. The results showed that the filter aid enhanced flocculation and coagulation of the fine cleaned coal slurry, enhanced the structure of the filter cake and promoted dewatering of the cake. Moisture content in the cake was reduced to 17% after vacuum filtration.

烧结用小球团质量评价新方法研究

伴随着更多的难制粒细粒铁精矿在烧结过程中的使用,多种新型的强化制粒方法被提出,造球是其中一种有效且重要的方法。相较于常规球团,这些烧结用球团通常粒径较小且工艺运行中的行为与常规球团不同,使用常规球团评价体系难以对其做出良好评价。分析了烧结用小球团在工艺运行过程中的受损情况,在常规球团质量评价体系的基础之上提出了由群料落下脱粉率、群料抗压脱粉率与干燥脱粉率组成的新型烧结用球团质量评价体系,并通过烧结工艺的特点和不同条件的测量实验,确定了恰当的测量参数。在与常规评价方法数据趋势高度吻合的前提下,新体系可以对烧结用小球团强度做出更精确、全面的评价,可以有效应用于小球团、烧结准颗粒的评价中,确保其强度达到工业要求水平,减少烧结工艺运行中粉料的产生。