中低品位磷矿真空碳热还原中磷元素的分离规律及冷凝回收机理

我国拥有丰富的磷矿资源，但富矿少、贫矿多，不能直接利用的中低品位磷矿(P2O5<26%)占90%以上。而且随着人们的开采，富矿已渐渐枯竭。因此，中低品位磷矿的开发利用是实现我国磷矿资源可持续发展的必经之路。基于此，首次提出真空碳热还原直接处理中低品位磷矿制备高品位磷单质的新工艺。本项目首先采用FactSage软件计算温度、压力和配碳量等因素对渣相和气相成分及其含量变化的影响规律，系统地了解其反应过程；在此基础上，深入研究真空碳热还原中低品位磷矿过程的反应热力学、多元多相体系的物相转变过程和反应动力学机理，以及磷元素的挥发与冷凝回收调控规律与机制；最终获得真空碳热还原处理中低品位磷矿制备高品位磷单质过程的物理化学特性，以期为我国中低品位磷矿高效清洁利用及工业化应用提供若干理论基础和技术支持。

Phosphate sources are rich in China, but little of which are rich ore. The indirect using low grade ore accounted for more than 90 percent (P2O5<26%). Now the rich ore has become less and less by more and more mining. So, how to exploit and use low grade ore must be the best way for sustainable development of phosphate rock resources. According to that, the new process of vacuum carbothermic reduction of low grade ore is proposed in this project. Firstly, for system understanding the reaction process, we should use the FactSage software to calculate the regular influence of factors like temperature，pressure and carbon content to the ore slag and gas phases components and quantities. Then, the reaction thermodynamics, phase transition of the multiple phase system, reaction kinetics mechanism, and the volatilization of phosphorus were researched during the vacuum carbothermic reduction of the mid-and-low grade phosphate rock, including the condensate recovery regulating mechanism. At last, we can gain the physicochemical characterization of the vacuum carbothermic reduction of the mid-and-low grade phosphate rock to prepare high grade simple substance phosphorus, which can provide some theoretical basis and technical support for efficient cleaning uses and industrial applications.