Design-of-experiment analysis of non-destructive detachment of electric parts from printed circuit boards of mobile phones using a cross-flow shredder. (October 2021)

• Record Type: Journal Article
• Authors: UEDA, Takao; FUKUSAWA, Hideaki; SUNAHARA, Naoki; YAMADA, Hiroshi; OKI, Tatsuya; KOYANAKA, Shigeki
• Is Part Of: Waste management. Volume 134(2021)
• Page Start: 52
• Page End: 56
• Publication Date: 2021-10
• Subjects: Design-of-experiment -- Parts detachment -- Cross-flow shredder -- Printed circuit board; PCB Printed circuit board -- CFS Cross-flow shredder -- DoE Design-of-experiment -- ANOVA Analysis of variance -- SS Sum of squares -- DF Degree of freedom -- MS Mean square; Hazardous wastes -- Periodicals; Refuse and refuse disposal -- Periodicals; 363.728
• DOI: 10.1016/j.wasman.2021.08.010
• Languages: English
• ISSNs: 0956-053X

Abstract

Graphical abstract: Highlights: A cross-flow shredder (CFS) suitable for design-of-experiment (DoE) was developed. Non-destructive detachment of electric parts from PCBs was investigated. DoE analysis was conducted on nine CFS factors. Four factors were statistically significant for non-destructive detachment. A future perspective on CFS improvement is presented, based on the results. Abstract: For minor metal recycling from electric parts, detachment without breakage (non-destructive detachment) of the electric parts from printed circuit boards (PCBs) is required. A cross-flow shredder (CFS), a drum-type chain mill, is often used in PCB recycling, but the effects of its individual features (e.g., chain thickness) on the non-destructive detachment of the PCB parts have yet to be understood. In this study, a CFS suited to the design-of-experiment (DoE) approach was developed; 27 different experimental conditions were evaluated, with three repetitions under each condition for a single PCB crushing, and the effect of nine CFS factors on the non-destructive detachment of parts from the PCBs of mobile phones was investigated. It was revealed that two factors (rotation rate and vent screen) have a statistically significant influence on such non-destructive detachment, and two other factors (chain-wall distance and crushing time) have a significant influence on related results such as the overcrushing of boards (PCBs after parts detachment) and powder generation. Based on these results, a future perspective on CFS improvement is presented.