Environmental Impacts Assessment of Liquid Crystal Extraction From Wasted LCD Panels

Abstract:

In view of the extraction of liquid crystal from the wasted LCD panels, this paper aims to analyze the raw materials consumption, energy consumption and emissions to the environment in the extracting process based on the method of Life Cycle Assessment (LCA). The environmental impacts of the recycling procedure are assessed with the aid of LCIA（Life Cycle Inventory Assessment）method and CML2001 method provided by LCA analyzing software Gabi 4. Two ways of liquid crystal extraction mentioned in the paper are supercritical method and distilling method. The assessment results indicate: the supercritical method’s LCIA result is 3 times higher than the distilling method, but the liquid crystal extracting rate can reach 95% with a lower raw materials consumption; the environmental impacts of distilling method is lower than supercritical method, but its extracting rate of liquid crystal can only get to 50%. For industrial applications, supercritical method has greater advantages and there are more crafts to perfect for distilling method in improving the recovery rate of liquid crystal.

• Periodical: Applied Mechanics and Materials (Volumes 496-500)
• Pages: 55-62
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.496-500.55
• Online since: January 2014
• Authors: Yu Lin Wang, Hai Juan Hu, Sen Qi, Guang Fu Liu
• Keywords: Distillation, Environmental Impact (EI), Extraction, Gabi 4, LCD Panel, Life Cycle Assessment, Liquid Crystal, Supercritical

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