Aiming at the problems of poor adaptability of raw materials,difficulty in treating low concentration SO₂ flue gas and low recovery rate of rhenium in the traditional molybdenum concentrate roasting-ammonia leaching method,molybdenum and rhenium were extracted from molybdenum concentrate by pressurized oxidative ammonia leaching method.The effects of factors such as ammonia dosage,copper salt additive dosage,liquid-solid ratio,kettle pressure,leaching temperature,leaching time and stirring speed on the leaching rates of molybdenum and rhenium were studied.The experimental results show that under the optimized conditions of ammonia excess coefficient of 1.27,copper salt additive dosage of 9%of molybdenum concentrate quality,liquid-solid ratio of 5∶1,kettle pressure of 2.8 MPa,leaching temperature of 160℃,leaching time of 5 h and stirring speed of 800 r/min,the leaching rates of molybdenum and rhenium are 96.85%and 99.29%,respectively.

The solubility of Nd₂O₃in the NaF-AlF₃molten salt system was systematically determined using the isothermal saturation method,with a focus on the effects of molten salt temperature(1010~1070℃)and NaF/AlF₃molar ratio(2.0~2.6)on its solubility.A first-order regression model correlating the solubility of Nd₂O₃with molten salt temperature and NaF/AlF₃molar ratio was established through experimental data fitting.The results demonstrate that the dissolution equilibrium of Nd₂O₃in the NaF-AlF₃molten salt is achieved in no less than 60 min,and the solubility significantly increases with increasing molten salt temperature and higher NaF/AlF₃molar ratio.The solubility of Nd₂O₃reaches a maximum value of 6.20%at 1070℃with a NaF/AlF₃molar ratio of 2.6.Within the experimental parameter range,the constructed regression model achieves a coefficient of determination(R²)of 0.983.

The ionic rare earth separation process generates a substantial amount of ammonium-containing wastewater.This wastewater contains high concentrations of impurities such as Ca and Mg,which can easily cause equipment scaling and significantly impair the normal operation of water treatment equipment.Based on this,this study employed the P507 extraction method to remove impurity elements from wastewater,the effects of phase ratio(O/A),ammonium concentration in ammonia-saponified organic phase,and extraction stage on the removal efficiency of three major impurity elements(Ca,Mg and Zn)were systematically investigated.Additionally,the Ca removal efficiency and treatment cost in practical production were analyzed.The experimental results indicate that under the conditions of P507 extractant concentration of 1.50 mol/L,O/A=3∶1,ammonium concentration in ammonia-saponified organic phase of 0.15 mol/L,extraction time of 5 min,stripping time of 10 min,and continuous three-stage countercurrent extraction,the concentrations of Ca,Zn and Mg in wastewater decrease to 1.42 mg/L,1.00 mg/L and 3.31 mg/L,respectively,with corresponding removal rates of 100%、97.49%and 99.67%,demonstrating a remarkably effective removal efficiency.In the practical production,under the process conditions of P507 extractant concentration of 1.5 mol/L,O/A=2∶1,ammonium concentration in ammonia-saponified organic phase not exceeding 0.10 mol/L,and continuous seven-stage countercurrent extraction,the P507 extraction method exhibits excellent Ca removal efficiency from the wastewater with a removal rate of over 90%,and the wastewater treatment cost is 16.75 yuan/t,which is superior to both the removal efficiency and treatment cost of the chemical precipitation method.This fully confirms the effectiveness and economy of P507 extraction method for treating high-calcium ammonium-containing wastewater generated from rare earth separation.

Driven by the demand for nickel in new energy battery technologies,lateritic nickel ore has emerged as the primary resource for nickel extraction.This article introduces the types of lateritic nickel ore and their compatibility with smelting processes,highlighting the development and industrial application of oxygen-enriched side-blown nickel smelting technology for lateritic nickel ore by CINF Engineering Co.,Ltd.(CINF).It provides a detailed analysis of the technical routes and energy consumption of three core processes—oxygen-enriched side-blowing smelting-reduction process(OESR),rotary kiln pre-reductionside-blown furnace reduction process(RKBF),and oxygen-enriched continuous converting high nickel matte technology(OECC),and also identifies the existing challenges in each process.This study provides references for the efficient smelting of lateritic nickel ore.

The SiO₂/MgO mass ratio significantly influences the microstructure,mineral composition,and reduction roasting product properties of low-grade lateritic nickel ore,thereby playing a crucial role in selecting and optimizing the process parameters for direct reduction-magnetic separation of the ore.This study investigated the influence of the SiO₂/MgO mass ratio on the product indicators of direct reductionmagnetic separation for low-grade lateritic nickel ore,explored the relationship between the SiO₂/MgO mass ratio and the optimal magnetic field strength for magnetic separation,and optimized process conditions,including slagging agent ratio,roasting temperature,and roasting time.The results indicate that the SiO₂/MgO mass ratio significantly affects the indicators of magnetic separation concentrate products.A lower SiO₂/MgO mass ratio fails to create favorable conditions for the reduction of valuable metals Ni and Fe.As the SiO₂/MgO mass ratio increases,the optimum magnetic field strength for magnetic separation gradually rises.The optimal SiO₂/MgO mass ratio,slagging agent ratio,roasting temperature,and roasting time are 2.81,5%,1350℃,and 2 h,respectively.Under these optimal conditions with a reducing agent ratio of 25%,ore particle size of-3 mm,grinding fineness of 80%passing-0.075 mm,and magnetic field strength of 2000 Oe,the magnetic separation concentrate product yields a Ni grade of 4.87%,Ni recovery rate of 90.34%,Fe grade of 85.95%,Fe recovery rate of 88.21%,Co grade of 0.29%,and Co recovery rate of 94.25%.

The gothite method was used to remove iron from the zinc sulfate neutralized solution in the hot acid leaching-iron removal system by jarosite method of a smelter and self-made zinc calcine leaching solution.The effects of raw material type,reduction time,initial acid concentration of solution,type of neutralizing agent for iron removal and gothite residue washing method on the reduction and iron removal process were analyzed.The results show that the combination of hot acid leaching and iron removal process by goethite method is feasible.For both self-made zinc calcine leaching solution and neutralized solution from zinc smelting workshop,the optimal reduction reaction time is 4 h,increasing the initial acid concentration of solution is beneficial to the reduction effect,and the iron precipitation effect of zinc calcine with particle size of-74μm is the best for iron removal neutralizer.After acid washing and water washing,the gothite residue produced from zinc calcine leaching solution after iron removal has a zinc mass fraction of 3.59%,an iron mass fraction as high as 39.62%,and a sulfur mass fraction of 4.91%.The experimental results of using neutralized solution from zinc smelting workshop for iron removal are not satisfactory,possibly due to the complex environment of the raw material system and the presence of a large number of cations,which has adverse influence on the reduction effect and the production of gothite residue.

今年5月,湖南省科技厅、湖南省财政厅联合启动2025年湖南省示范性科技成果转化项目申报工作,围绕湖南省现代化产业体系布局,聚焦2021年以来企业与高校、科研院所共同研发且已取得关键技术突破和突出产业化效果、拟持续进行技术迭代和成果产业化的科技成果转化项目。今年8月,湖南省科技厅发布立项结果,本次全省仅15个项目立项。长沙有色冶金设计研究院有限公司(简称长沙有色院)申报的“深地资源安全高效开发与灾害动态协同防控技术研究与应用”从众多项目中脱颖而出,成功入选。

近日,长沙有色冶金设计研究院有限公司(简称长沙有色院)“复杂含锌物料超大型流态化焙烧技术与装备”“锌基多源固废协同资源化关键技术与大型化装备”“铅锌冶炼废水无钠硫化深度除铊脱砷与资源化利用技术研发与应用”“极高寒特大型露天矿低碳高效开采集成技术与工程示范”“深井矿山高应力围岩承压调控支护技术研究及应用”“强岩溶区超细矿泥建库安全堆存成套技术创新开发与应用”“露天矿高边坡安全监测新技术与智能装备”7项科技成果通过中国有色金属工业协会鉴定评价,专家组一致认为7项科技成果技术创新程度高、技术经济指标先进,整体技术达到国际领先水平。