Nonmetallic fractions are essential byproducts of the physical-mechanical recycling process of waste printed circuit boards. Large amounts of metals remain in fine nonmetallic fractions because it is very hard for recycling metals from fine size fraction by traditional technologies. In this study, a vibrated gas-solid fluidized bed was utilized to recover residual metals from fine particles (−0.25 mm size) of nonmetallic fractions obtained from the corona electrostatic separation process. The basic mineralogical characteristics and properties of nonmetallic fractions with a size of −0.25 mm indicated that a considerable amount of clavate glass fibers existed in these nonmetallic fractions. The content of residual metals in the −0.25 mm nonmetallic fractions was up to 19.84 wt%. The major metallic elements found in the nonmetallic fractions were Fe, Cu, Pb, and Sn. The results indicated that removing glass fibers from nonmetallic fractions by triboelectric separation can strengthen the gravity-segregation process between heavy and light particles in fine nonmetallic fractions, resulting in improved metal recovery from 76.39% to 81.41%. Based on this research, an industrial flowsheet for the recovery of metals from fine WPCBs is proposed.

非金属部分是废印刷电路板物理机械回收过程中必不可少的副产品。大量金属保留在精细的非金属馏分中，因为用传统技术很难从精细粒度的馏分中回收金属。在这项研究中，振动气固流化床用于从电晕静电分离工艺获得的非金属级分的细颗粒（-0.25毫米大小）中回收残留金属。尺寸为-0.25 mm的非金属级分的基本矿物学特征和性质表明，在这些非金属级分中存在大量的棒状玻璃纤维。在-0.25mm非金属级分中残留金属的含量高达19.84wt％。在非金属部分中发现的主要金属元素是Fe，铜，铅和锡。结果表明，通过摩擦电分离去除非金属级分中的玻璃纤维可以增强细小非金属级分中重粒子和轻粒子之间的重力分离过程，从而将金属回收率从76.39％提高到81.41％。基于这项研究，提出了一种从细WPCB中回收金属的工业流程图。