热处理和添加煤焦油对褐煤可磨性与可浮性影响的研究

Research on the influencing of heat treatment and coal tar on grindability and floatability of lignite

褐煤表面具有很强的亲水性,导致其在常规浮选条件下很难得到有效浮选。试验在对难浮褐煤进行热处理的基础上,采用在干法球磨褐煤过程中添加煤焦油的方法对其进行预处理,并分别研究了热处理和添加煤焦油对褐煤可磨性和可浮性的影响。HGI可磨性指数测试试验表明,在热处理条件下,褐煤的水分越少,HGI指数越低;添加的煤焦油越多,HGI指数下降幅度越大。褐煤预处理后的浮选试验表明,煤焦油用量越多,精煤灰分越低,可燃体回收率越高。FTIR光谱分析得出,热处理和添加煤焦油后褐煤的疏水性都得到增强。

Due to there is strongly hydrophilic on surface of lignite and thus it is difficult to float with conventional flotation reagents. On the basis of heating treatment of difficult to float lignite,and adding the coal tar during the process of dry grinding of lignite,investigated influence of heat treatment and dry grinding on grindability and floatability of lignite. The results of HGI experiment shows that grindability index of lignite reduced with the decreasing of moisture under the heat treatment condition; HGI index sharply declines when there is more coal tar added. The flotation experiment with coal tar in dry grinding shows that the more the coal tar is added,the lower ash content of clean coal,and the higher combustible material recovery rate. FTIR spectra analysis shows that hydrophobicity of lignite enhanced after the low- temperature heat treatment and adding coal tar.