Predicting the specific size yield of crushed WPCBs based on the breakage probability model

Abstract

Waste printed circuit boards (WPCBs) contain a significant amount of valuable components found in e-waste, including numerous metals and can be considered as secondary resources. Crushing is the primary stage for recycling useful components from WPCBs. Due to the varying dominant sizes of different separation processes, the size distribution of crushed WPCBs plays an important role in determining recovery efficiency. Therefore, controlling the size of crushed products is essential for improving recovery rates. A method for calculating the specific size yield of crushed WPCBs was proposed based on the breakage probability model. The mass yield and copper yield smaller than a certain size were fitted using the breakage probability model. The applicability of different breakage probability models was investigated, and the calculating method for specific size yield was verified. Excellent fitting applicability in mass yield and copper yield of crushed WPCBs was demonstrated by the Logistic model. The variation of mass yield and copper yield smaller than a certain size with energy can be effectively predicted. The theoretical specific size yield can be calculated by the difference between the theoretical yields smaller than different sizes. The prediction of specific size mass yield and copper yield can effectively promote the pre-concentration during crushing and help to optimize the crushing process. The utilization of the breakage probability model in WPCBs has the potential to improve component recovery and serve as a benchmark for optimizing the crushing process of other e-wastes.