隐晶质石墨浮选脱硫试验研究

Research on desulfurization of aphanitic graphite

针对湖南某碳品位60%,含硫1%的隐晶质石墨矿进行浮选脱硫试验研究,以提高石墨产品的利用价值。石墨中的有害元素硫主要以黄铁矿、磁黄铁矿等形式存在。浮选过程中石墨对含硫矿物表面有罩盖行为,致使含硫矿物表面性质与石墨单体的性质相近,无法选择性分离,最终导致精矿中含硫高,且难以通过一般方法脱硫。本研究通过氧化调浆、分散调浆和抑制调浆的方法进行浮选试验,发现脱硫抑制剂OL-IIC可以有效抑制石墨对黄铁矿的包裹行为,并能够将石墨中的硫元素含量降低至0.24%,同时保证较好的浮选指标。经一粗三精两扫闭路工艺选别后,得到精矿产品碳品位80.25%、回收率81.27%,硫含量0.23%的浮选指标。

This paper presents the research on desulfurization of aphanitic graphite ore（from Hunan）,which contains 60% carbon and 1% sulfur minerals.Phase and chemical analyses revealed that the harmful impurity element sulfur existed mainly in pyrite and pyrrhotite.Microscopic identification results showed that graphite had coverage effects on sulfur minerals,leading to similar surface properties with graphite.These similarities caused non-selective flotation,and resulted in a difficult desulfurization.Based on these characteristics,different oxidant,dispersant and inhibitor were chosen to strengthen pulp flotation.Experimental tests suggested OL-IIC（served as inhibitor）contributed best in graphite coverage effects inhibition,with a good flotation index.The closed-circuit floatation process indicated that the graphite concentrate obtained carbon grade 80.25% and recovery 81.27%,with 0.23% sulfur contented.