滇池地区磷块岩中倍半氧化物的赋存特征

磷矿中的倍半氧化物会导致后续湿法磷酸过滤困难，降低设备生产能力。为降低磷矿中的倍半氧化物含量，利用荧光光谱仪(XRF)、偏光显微镜、扫描电镜(SEM)、矿物参数自动定量分析系统(MLA)等分析手段，查明了磷矿矿物组成特征、倍半氧化物的赋存特征、磨矿分异特征、赋存矿物单体解离特征等。结果表明：Fe₂O₃主要赋存在褐铁矿中，主要呈集合体形式集中分布、星点状分散分布、侵染状分布、脉状分布；Al₂O₃主要赋存在白云母、水云母中，呈碎片状，为层状硅酸盐矿物；磨矿后，Fe₂O₃、Al₂O₃均有向细粒级富集的分异特征，且单体解离情况较好，为选矿脱除提供了基础条件。褐铁矿和层状硅酸盐矿物表面具亲水性，磷矿反浮选工艺难以脱除，建议采用正浮选工艺脱除。

Study on the Occurrence State of Sesquioxide in Phosphorite in Dianchi Area

In order to reduce the content of sesquioxide in phosphate ore concentrate and improve the quality of wet process phosphoric acid, XRF, polarizing microscope, SEM, MLA and other technical means were used to identify the mineral composition characteristics of phosphate ore, the occurrence characteristics of sesquioxide, grinding differentiation characteristics, and the dissociation characteristics of the host mineral monomer. The research results show that Fe₂O₃ mainly exists in limonite, mainly in the form of aggregation, star point dispersion, infection and vein distribution; Al₂O₃ is mainly hosted in muscovite and hydromica, in the form of fragments, and is a layered silicate mineral. After grinding, both Fe₂O₃ and Al₂O₃ exhibit differentiation characteristics towards fine-grained enrichment, and the monomer dissociation is good, providing a basic condition for mineral processing and removal. The surface of limonite and layered silicate minerals is hydrophilic, and it is difficult to remove phosphate rock by reverse flotation process.