锡元素在电子废料协同熔炼过程的定向迁移调控研究

Electronic waste is an important secondary resource of tin, improving the recovery rate of tin in the process of electronic waste recovery has important practical significance for the sustainable development of tin industry. At present, there are many problems in the process of electronic waste collaborative smelting, such as complicated tin distribution behavior and diverse forms, which result in low tin recovery rate and great harm to the subsequent disposal of crude copper. This project is to be carried out the migration behavior and directional regulation entry slag mechanism of tin in the process of electronic waste collaborative smelting. Firstly, the physical and chemical characteristics of tin in raw materials were obtained by means of analysis and testing, and the phase equilibrium relationship of tin in the three-phase region and its influencing factors were obtained by means of thermodynamic calculation. On this basis, the migration path of tin in three phases in the high temperature collaborative smelting process was analyzed using high temperature experiment with test, the influence of symbiotic elements on the migration behavior of tin was explored. Based on the first-principles method, the possible product forms of tin in the smelting process were analyzed, and the mathematical model of smelting conditions and tin product forms was constructed. Combined with molecular dynamics method analysis, study the phase precipitation condition of tin in melt, establish the regulation mechanism of tin migration into slag in the form of tin oxide, and study the crystal structure change rule of SnO to SnO·SiO2 phase transformation in slag, so as to reveal the regulation mechanism of phase transformation process.

电子废料是锡的重要二次资源，提高电子废料回收过程中锡的回收率对该产业的可持续发展有重要的现实意义。目前电子废料协同熔炼过程存在锡分配行为复杂和形态多样等问题，致使锡回收率低，且对后续粗铜处置带来极大危害。本项目拟开展电子废料协同熔炼过程锡的迁移行为及定向调控入渣机制研究。项目首先采用分析测试手段获得原料中锡的赋存形态及理化特性，通过热力学计算得到锡在三相区内的相平衡关系及其影响因素；在此基础上，采用高温实验及分析测试，解析高温协同熔炼过程锡在三相中的迁移路径，并探究共生元素对锡的迁移行为影响；基于第一性原理方法解析熔炼过程锡可能存在的产物形态，构建熔炼条件与含锡产物形态的数学模型；结合分子动力学方法，研究熔体中含锡物相析出条件，建立熔体中锡以氧化亚锡形式迁移入渣的调控机理，研究熔渣中SnO向SnO·SiO2物相转化晶体结构变化规律，揭示物相转化过程的调控机制。

电子废料是锡的重要二次资源，提高电子废料回收过程中锡的回收率对该产业的可持续发展有重要的现实意义。目前电子废料协同熔炼过程存在锡分配行为复杂和形态多样等问题，致使锡回收率低，且对后续粗铜处置带来极大危害。本项目开展了电子废料协同熔炼过程锡的迁移行为及定向调控入渣机制研究。采用分析测试手段获得典型电子废料中锡、铜、镍等有价金属的赋存形态及理化特性，通过热力学计算得到有价金属在三相区内的相平衡关系及其影响因素；采用FactSage软件绘制了多元渣系相图，考察了炉渣熔化温度和粘度的影响因素，确定了合理的渣型范围。在此基础上，采用高温实验及分析测试，解析高温协同熔炼过程有价金属在三相中的迁移路径，并探究了共生元素对锡的迁移行为影响；为电子废料、含铜二次物料大规模高效、清洁、综合回收提供基础理论指导。