Recovery of valuable components from waste LCD panel through a dry physical method

A waste liquid crystal display (LCD) panel was recycled synthetically and cleanly by using dry physical methods, namely, mechanical exfoliation, dry crushing and vibrated gas-solid fluidized bed separation. Results of elemental and phase analyses show that indium and tin contents were enriched greatly in indium tin oxide concentrate obtained from colour filter and thin-film transistor glass. The results of crushing, ash content and scanning electron microscopic analyses show that when the LCD panel was crushed into particles smaller than 0.25 mm, the polarizer film is nearly completely liberated from the glass. Moreover, the results of vibrated gas-solid fluidized bed separation show that gas velocity and separation time are the main factors influencing the separation. The vibration intensity of 6.8, gas velocity of 13.6 cm/s and fluidizing time of 30 s are the optimum operating parameters, and the degree of separation and recovery of polarizing film reached up to 37.69 and 72.3%, respectively. Based on these results, the combination of dry enrichment, dry crushing and dry separation in a flowsheet is proposed for recycling of waste LCD panel.