Triboelectrostatic separation for granular plastic waste recycling: A review

Over the past decades, China has been suffering from negative environmental impacts from distempered e-waste recycling activities. After a decade of effort, disassembly and raw materials recycling of environmentally friendly e-waste have been realized in specialized companies, in China, and law enforcement for illegal activities of e-waste recycling has also been made more and more strict. So up to now, the e-waste recycling in China should be developed toward more depth and refinement to promote industrial production of e-waste resource recovery. Waste printed circuit boards (WPCBs), which are the most complex, hazardous, and valuable components of e-waste, are selected as one typical example in this article that reviews the status of related regulations and technologies of WPCBs recycling, then optimizes, and integrates the proper approaches in existence, while the bottlenecks in the WPCBs recycling system are analyzed, and some preliminary experiments of pinch technologies are also conducted. Finally, in order to provide directional guidance for future development of WPCBs recycling, some key points in the WPCBs recycling system are proposed to point towards a future trend in the e-waste recycling industry.

Disposing and recycling waste printed circuit boards: disconnecting, resource recovery, and pollution control.

Liberation characteristic and physical separation of printed circuit board (PCB).

Recovering full metallic resources from waste printed circuit boards: A refined review

The technology industrialization was the final goal of the research. A set of automatic line without negative impact to environment for recycling waste printed circuit boards (PCB) in industry-scale was investigated in this study. The independent technologies were integrated and many problems in the process of technology industrialization were solved. The whole technology contained four parts: multiple scarping, material screening, multiple-roll corona electrostatic separator, and dust precipitation. The output of this automatic line reached 600 kg/h and the recovery rate of copper reached 95%. After separation, the metal and nonmetal products were totally reused. Compared with other production lines (traditional fluid bed production line and processing from developed countries), the automatic line has lower energy consumption and better technology rationality. The cost of this line was in acceptable level for local processors.

Environmental friendly automatic line for recovering metal from waste printed circuit boards.

Electrostatic separation is an effective and environmentally friendly method for recycling waste printed circuit board (PCB) by several kinds of electrostatic separators. However, some notable problems have been detected in its applications and cannot be efficiently resolved by optimizing the separation process. Instead of the separator itself, these problems are mainly caused by some external factors such as the nonconductive powder (NP) and the superficial moisture of feeding granule mixture. These problems finally lead to an inefficient separation. In the present research, the impacts of these external factors were investigated and a robust design was built to optimize the process and to weaken the adverse impact. A most robust parameter setting (25 kv, 80 rpm) was concluded from the experimental design. In addition, some theoretical methods, including cyclone separation, were presented to eliminate these problems substantially. This will contribute to efficient electrostatic separation of waste PCB an...

Electrostatic separation for recycling waste printed circuit board: a study on external factor and a robust design for optimization.

Silicon (Si) is one of the most promising anode materials for high-energy lithium-ion batteries. However, the widespread application of Si-based anodes is inhibited by large volume change, unstable solid electrolyte interphase, and poor electrical conductivity. During the past decade, significant efforts have been made to overcome these major challenges toward industrial applications. This review summarizes the recent development of microscale Si-based electrodes fabricated by Si microparticles or other industrial bulk materials from the perspective of industrialization. First, the challenges for microscale Si anodes are clarified. Second, structural design strategies of stable micro-sized Si materials are discussed. Third, other critical practical metrics, such as robust binder construction and electrolyte design, are also highlighted. Finally, future trends and perspectives on the commercialization of Si-based anodes are provided. 

Yufei Qin

Papers

Electrostatic separation for recycling waste printed circuit board: a study on external factor and a robust design for optimization.

The pursuit of commercial silicon-based microparticle anodes for advanced lithium-ion batteries: A review

Impact of nonconductive powder on electrostatic separation for recycling crushed waste printed circuit board.

Emission of PAHs, PCBs, PBDEs and heavy metals in air, water and soil around a waste plastic recycling factory in an industrial park, Eastern China.

Quadratic nonlinear models for optimizing electrostatic separation of crushed waste printed circuit boards using response surface methodology.