有色金属复杂资源低温碱性熔炼基础研究

The nonferrous metals industry in China is facing the resource, energy and environment problems. Refractory resources are the main developing objects, which can not be cleanly treated by conventional processes. Low-temperature alkaline smelting has the advantages of high efficiency and high selectivity, showing great promising applications in the field of refractory resource processing. In this study, the primary mineral resources including beryllium bearing bismuth -molybdenum sulfide and gold bearing antimony sulfide,and secondary resources including anode slimes originated from copper, lead and tin metallurgical process are choosen to be the research objects. Taking both the effective-clean resource processing and comprehensive recovery of nonferrous metals as the targets, the key scientific issues in the low-temperature alkaline smelting processing of refractory resources are to be solved through fundamental & theoretical study systematically. Firstly, through the physical and chemical investigation of low-temperature alkaline melt and the thermodynamic behavior analysis of the process, the system structure and component behaviors in the low-temperature alkaline smelting of multi-metal refractory resources are to be determined. Secondly, through the studies on the element interfacial behaviors and kinetic characteristics both in the reduction smelting of mineral resources and in the oxidation smelting of secondary resources, the component interaction laws in the low-temperature alkaline smelting are to be revealed. Finally, through the studies on molten salt system and multi-factor effects in the process, the optimum conditions and process regulation are to be determined. Based on above achievements, the fundamental & theoretical system of low-temperature alkaline smelting will be established. Novel method for low-temperature alkaline extractive metallurgy is developed,providing the theoretical support for the processing of refractory nonferrous metal resources.

我国有色金属工业面临严重的资源、能源和环境约束问题，复杂难处理资源成为主要开发对象，常规冶金工艺难以清洁处理，低温碱性熔炼以其高效、高选择性展示出良好的应用前景。本研究以我国大量的含铍硫化铋钼矿、含金硫化锑矿等复杂一次资源和铜、铅、锡冶炼过程产生的阳极泥等二次物料为对象，以资源高效清洁处理及有价金属综合回收为目标，通过系统深入的基础理论研究，重点解决复杂资源低温碱性熔炼过程冶金关键科学问题。①通过低温碱性熔体物化性质研究及过程热力学行为分析，明晰多金属复杂资源低温碱性熔炼体系结构及组元行为；②探讨低温碱性条件下复杂一次资源还原熔炼、二次资源氧化熔炼过程元素界面作用行为及动力学特征，揭示低温碱性熔炼过程组元交互作用规律；③通过熔盐体系及熔炼过程多因素作用影响研究，确定优化工艺参数及过程调控机制。建立低温碱性熔炼过程理论体系，形成低温碱性熔炼提取冶金新方法，为有色金属复杂资源处理提供理论依据。

我国原生资源矿石品位不断下降，低品位复杂资源成为主要开发对象，现有冶金工艺难以适应，存在金属回收率低、低浓度SO2烟气污染严重、产生大量高危固废等问题。本项目以含金硫化锑矿、铜阳极泥等典型有色金属复杂资源为研究对象，开展了低温碱性熔炼处理基础研究。.（1）开展了低温碱性熔炼过程热力学和熔体物化性质研究。自制β(β″)-Al2O3固体电解质管并构建电池，测定了反应产物Na2SnO3、Na2PbO2、NaSbO3、Na2TeO3等产物的生成自由能以及各熔锍体系中S活度；测量了NaOH-Na2SO4-Na2S和Na2CO3-Na2SO4-Na2S熔体中CO2的溶解度；测定了NaOH-Na2CO3、NaOH-Na2CO3-Na2SO4等体系熔盐的软化点、熔融温度、粘度、表面张力和密度等性质。.（2）开展了低温碱性还原熔炼处理含金硫化锑矿研究。明确了Na2CO3-NaCl共晶熔盐的物理化学性质；计算了低温熔盐炼锑各反应ΔGθ-T关系；确定了还原固硫反应动力学参数；明确了伴生金属Pb、Bi、Cu以及Al2O3和SiO2脉石行为；以Na2CO3-NaCl为熔炼体系，以ZnO为固硫剂，在700-900ºC温度下还原固硫熔炼，一步产出粗锑并富集金，锑直收率92.88%、水浸渣含锑1.56%、金捕集率达95%以上，综合固硫率99.58%，S主要以ZnS和FeS形态存在。.（3）开展了低温碱性氧化熔炼处理铜阳极泥研究。明确了NaOH-NaNO3熔盐的物理化学性质，分析了熔炼过程中各金属热力学行为，计算了水溶液中金属离子的分布状态。NaOH体系中，Se和As转化率分别为96%和97%，99%以上的Cu、Pb、Sb、Te及贵金属富集在渣中；NaOH-NaNO3体系中，Se、As、Pb和Sn转化率分别为97%、98%、76%和86%，Cu、Sb及贵金属富集在渣中。针对熔炼-浸出后得到的强碱溶液和重贵金属渣，进行了Se、Pb、Sn、Cu、Te、Sb的进一步分离富集探索。.项目建立了低温碱性熔炼过程的理论体系，确立了有色金属复杂资源处理新方法，形成了低温碱性熔炼新技术，为重金属矿产资源的低温清洁冶金及二次金属资源中有价金属提取回收提供了理论依据和技术原型。项目发表学术论文70篇，撰写专著2本，授权国家发明专利20项，实用新型专利3项，获省部级科学技术进步奖一等奖3项。