The Yangla copper pyrite comprehensive utilization of resources Xuanye test
|School||Kunming University of Science and Technology|
|Course||Mineral Processing Engineering|
|Keywords||pyritic flotation chloridizing roasting response surface analysis comprehensive utilization|
Boasting profound mineral resources, China’s mineral resources generally features in too much poor grade mines, complex property, difficulty in processing mines, low comprehensive utilization of accompanying resources and substantial waste. China enjoys the largest reserve of pyritic in the world, which has always been used as sulfur resource. The poor grade of pyritic for acid making causes a low-grade Fe and a high-grade S in cinder which can’t be directly used as iron raw material. Meanwhile the accompanying useful elements such as copper, lead, zinc, gold, silver and other precious or non-ferrous metals can’t be better exploited remaining in the cinder. Therefore, this article carry’s out a theoretical and experimental research on the pyritic within copper of Yangla in Yunnan on the perspective of comprehensive utilization of pyritic.Presently, a process of bulk flotation is used by separating refined Cu and S mine, with 70～80% recovery of Cu and 10～20% lost in refined S mine. The refined S mine contains S 30.52%, Cu 1.15%, Au 0.8g/t, while Fe and S exists as pyrite or pyrrhotite. With regard to the inefficiency using of pyritic to make acid, a new method of beneficiation-metallurgy combination processing called depth flotation-high temperature chloridizing roasting had been used for comprehensive utilization of pyritic. Firstly, the deep flotation method is used to extract refined S mine with the iron grade in cinder more than 60%. Secondly, the cinder was chloridizing roasted at a high temperature to recycle the Cu and Au, and then the pellet could be used as raw material of iron making.By depth flotation experimental study carried on the pyrite, a final concentrate of 38.25% S grade with 94.79% recovery was achieved with a circuit of once rough floatation followed by twice scavenging and twice concentrating, in which 50.19% Fe with 87.36% recovery,1.48% Cu with 96.58% recovery and 1.0g/t Au with 91.77% recovery. The good flotation quota achieved the goal of depth flotation and created the conditions for recycling of copper, iron and gold resource.Then oxidizing roasting experimental study was carried on the final concentrates of depth flotation. The results indicated that a slag containing copper with 60.27% Fe had been obtained, and the content of poisoning elements like S, As, Pb and SiO2 is in accordance with the requirement of refined iron mine. The slag could be used as raw material of iron making after Cu and Au retrieved by high temperature chloridizing roasting.The oxidizing roasting products had high grade with 1.61% Cu and 1.2g/t Au. The results of high temperature chloridizing roasting indicated that the Cu evaporation rate was about 97% and the Au evaporation rate was about 87%. The high temperature chloridizing roasting was carried at 1150℃for 30min with 5% CaCl2 in the pellet. On that basis, the conditions of high temperature chloridizing roasting were been optimized by Design Expert using response surface analysis which gives four technological parameters with low chlorating, which could be used to guide the industrial production.