陕西省宁强县宽川铺磷稀土矿选矿试验研究

Experimental study on beneficiation of phosphate-rare Earth Ore occurring in Kuanchuanpu area,Ningqiang county of Shaanxi province

扬子地台北缘分布着丰富的磷矿,其中牛蹄塘组含磷地层还伴生有丰富的稀土。陕西省宁强县宽川铺磷矿是上世纪五十年代发现的一个低品位磷矿床,磷矿矿石矿物主要为胶磷矿(碳氟磷灰石)、泥质、石英、方解石、白云石、黄铁矿、炭质。在选取的磷矿石样品中P_(2)O_(5)品位1.13%~21.03%,物相分析表明碳氟磷灰石中P_(2)O_(5)含量5.08%,分布率97.65%。该磷矿中含有丰富的稀土,稀土(REO)品位200×10^(-6)~1726×10^(-6)之间。上世纪九十年代作为磷矿开采一段时间,后由于P_(2)O_(5)品位太低,开采成本上升,大部分已经停产。随着全球战略性资源稀土的稀缺性,稀土越来越被重视。实施陕西省地勘基金项目、陕西省科技厅工业科技攻关项目,针对陕南地区磷矿伴生稀土进行研究,入选矿石品位P_(2)O_(5)为5.49%,稀土(REO)为505.40×10^(-6)取得了较好的选矿效果。通过选矿试验研究,摸索出“浮选-两段酸浸-分步沉淀提取磷和稀土选冶工艺流程”,获得沉磷固体活性磷酸钙Ca10(PO4)6(OH)2产品(HG/T3583-2009),P_(2)O_(5)品位38.45%,P_(2)O_(5)回收率78.69%;草酸稀土REO品位为1.59%,REO回收率为74.53%。

The northern edge of Yangzi Platform is rich in phosphate ore and the phosphorus-bearing stratum of Niutitang Formation is accompanied by rich rare earth.The Kuanchuanpu Phosphorus Mine in Ningqiang County,Shaanxi Province is a low-grade phosphate deposit found in the 1960s.The phosphate ore minerals are mainly collophanite(carbon fluoroapatite),mud,quartz,calcite,dolomite,pyrite and carbon,in which the P_(2)O_(5) grade ranges between 1.13%and 21.03%.Phase analysis indicates that the P_(2)O_(5) with a content of 5.08%in fluorocarbon apatite has a distribution rate 97.65%.Based on experimental researches on mineral processing of associated rare earth in phosphate ores in southern Shaanxi,in which the selected ore grade P_(2)O_(5)5.49%and rare earth(REO)505.40×10^(-6),a good beneficiation effect has been made by means of"flotation-two acid immersion-step precipitation extraction phosphorus and rare earth smelting process",achieving Ca10(PO4)6(OH)2 product(HG/T3583-2009),P_(2)O_(5) grade 38.45%,P_(2)O_(5) recovery rate 78.69%,REO grade 1.59%with REO recovery rate 74.53%.