破碎电子废弃物多形状有色金属涡流分选电磁感应机理与分离模型

Current forms and intensities of the induced eddy currents of nonferrous metallic fragments, which having complex shapes,in the changing magnetic field of eddy current separator will be studied. Meanwhile,configurations and intensities of the induced magnetic fields by the eddy currents will also be researched.The methods of electromagnetism,mechanical dynamics,and computer simulation will be employed.Based on the principle of repulsive force generated in cocurrent magnetic poles,the models of repuslive force (eddy current force)of nonferrous metallic fragments, which having complex shapes,in eddy current separation will be constructed by considering the fragment as "new magnetic pole" to the magnetic pole of eddy current separator. The subjected forces and movement behaviors of nonferrous metallic fragments in eddy current separation will be analysed. Then, based on the models of eddy current force,the trajectory models of nonferrous metallic fragments in different position of the changing magnetic field will be constructed. The trajectory models can be used to predict the ending position and separation rate of fragments in eddy current separation as well as guiding the separation process. At last,separation criterions of nonferrous metallic fragments that having complex shapes will be established by the orthogonality experiences of eddy current separation and reverse concluding of trajectory models. This project will not only provide the theoretical basis for the successful separation of nonferrous metals from crushed e-waste by eddy current separation, but also present the scientific information for the development of new eddy current separator.The implementation of this project will be very significant to treatment and recycling of e-waste.

根据电磁学、机械动力学理论、利用计算机模拟仿真技术，研究在涡流分选器磁辊转动激发的变化磁场内,破碎电子废弃物多形状有色金属碎片的感应涡电流、感应磁场形态。基于同向磁极互相排斥的原理，视多形状有色金属碎片为"新磁极"，建立有色金属碎片（新磁极）与磁辊磁极间的排斥力（涡流力）计算模型。分析多形状有色金属碎片在变化磁场中的受力特征与运动行为，结合涡流力计算模型，构建多形状有色金属碎片在磁场不同位置的运行轨迹模型，以预测碎片涡流分选"归属点"及分离率，指导涡流分选实践。通过涡流分选正交实验，利用轨迹模型逆向推导、研究多形状有色金属碎片与其他颗粒的涡流分选临界分离条件，建立临界分离判据，用以指导新型涡流分选器的开发。本研究丰富了破碎电子废弃物有色金属的涡流分选理论，为新型涡流分选器的研发提供了科学基础，对我国电子废弃物无害化处理和资源化利用具有重要意义。

由于缺少绿色、高效的资源化技术，我国电子废弃物的回收造成严重的环境污染和巨大的资源浪费。本项目提出利用涡电流分选的方法对破碎电子废弃物中的有色金属进行绿色、高效分选。着重研究了多形状有色金属碎片在涡流分选过程中的感应涡电流、感应磁场产生机理。建立了多形状有色金属碎片在涡流分选过程中的涡流力模型、在磁场不同位置的运行轨迹模型，并且得出了多形状有色金属碎片从混合物料中分离的临界分离判据。项目研究成果突破了传统涡流分选设备在破碎电子废弃物有色金属分选中分离率低的技术瓶颈，使得电子废弃物中有色金属颗粒的涡流分选一次分离率达95%以上，节约生产成本（劳动力成本）70%。 项目的实施为我国电子废弃物有色金属的资源化提供了高效、环保的技术与装备，促进了我国循环经济的发展。