Multipurpose utilization of iron resources in pyrite cinder with high sulfur and extremely poor iron in Heishu Mining Area, Zhenxiong County, Northeast Yunnan Province

There is a large amount of pyrite cinder in Northeast Yunnan Province, which is difficult for multipurpose utilization, and has caused significant environmental geological problems. In this paper, the pyrite cinder of Heishu Mining Area in Zhenxiong County of Northeast Yunnan Province is taken to conduct a multipurpose utilization study for iron resources, in order to obtain high-quality iron concentrate by the beneficiation test, so as to provide an effective and practical technical method for the multipurpose utilization of pyrite cinder in this area. The pyrite cinder in Heishu Mining Area is weak magnetic, and has high sulfur content more than 2% and extremely poor iron content less than 30%. In this paper, systematic beneficiation test on this type of pyrite cinder has been carried out, including the exploration test, iron concentrate recovery test and reverse flotation desulfurization test. The research results show that the main process of wet magnetic-gravity method can effectively enrich the useful component iron, and effectively remove the harmful component phosphorus. And then iron concentrate with iron content over 60%, phosphorus content below 0.25% and sulfur content below 0.30% can be obtained by the reverse flotation desulfurization test, to meet the requirements of industrial indicators for iron ore used in ironmaking, while the effective recovery rate is 49.08%. Therefore, it has a bright future that the beneficiation process of “magnetic-gravity and reverse flotation” used for multipurpose utilization for iron resources by using pyrite cinder with high sulfur and extremely poor iron, especially the main beneficiation process is friendly to the environment which does not produce secondary pollution. The success of beneficiation test for iron resource by using pyrite cinder of Heishu Mining Area is of great significance for the resource utilization, reduction and harmless disposal of pyrite cinder and other solid waste in Northeast Yunnan Province, and to fulfill the role of ecological barrier in the upper reaches of the Yangtze River in the Northeastern Yunnan Province.