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CORDIS - Resultados de investigaciones de la UE
Contenido archivado el 2024-05-29

Liquid crystal display re-use and recycling (ReLCD)

Final Report Summary - RELCD (Liquid crystal display Re-use and recycling)

Liquid crystal displays (LCDs) are widely used nowadays, dominate the flat panel technology and are expected to surpass the well-established colour cathode ray tubes (CRTs) in terms of revenues in the near future. Currently, the only way to deal with LCDs after the end of their commercial life is to dispose them in waste incinerators or landfills; however there are considerable doubts regarding the environmental impact of this process. As a consequence, the European Commission requested the disassembly of LCDs with an area bigger than 100 cm2 in the proposal for a Directive of the European Parliament and the Council on Waste Electrical and Electronic Equipment (WEEE Directive).

The RELCD project methodology followed the logical processing steps of redundant LCDs within a modern recycling plant, aiming to recover LCDs at the maximum possible level through various options, such as upgrade, reuse, recondition, remanufacture, recycling of materials and disposal. The RELCD specific objectives were to:

1. identify a cheap and fast test methodology to verify whether the obsolete or excess LCDs were still working
2. develop a technology for the refurbishment of working LCDs and their reintegration into repair and in exemptions in production processes
3. identify a test method to detect hazardous substances in liquid crystal (LC) mixtures
4. develop an ecologically efficient disassembly and recycling technology for the non operating LCDs that would fulfil the WEEE Directive
5. develop, implement and test an integrated pilot plant system incorporating the proposed technologies
6. examine possible improvements of the existing LCD design and production in order to improve the sustainability of the products' life cycle.

The project was organised in four distinct, yet interrelated, work packages (WPs), each of which focussed on the following issues:

1. functionality tests and refurbishment of working units. As part of this WP a previously developed test strategy was refined and a database containing technical information on LCD modules was developed. In addition, a methodology for the refurbishment of utilised equipment was identified.
2. disassembly, identification of materials and material recycling, which included analysis of LCD components to define the most feasible recycling options. It occurred that only two of the components could be reused by means of a reprocessing step. In order to characterise the possible fillers in these recoverable components, several calcinations tests were carried out. Moreover, alternative recycling schemes, such as manual dismantling and mechanical treatment were considered within the framework of a recycling strategy.
3. design, implementation and evaluation of a laboratory scale pilot system. Numerous treatment technologies were assessed considering various parameters. Manual dismantling achieved the best results and a relevant strategy was formulated. In addition, mechanical treatment was selected as the most feasible recycling option for LCDs without mercury (Hg) lamp recycling. The functionality test layout was prepared and examined under different scenarios, while special LCD model equipment was developed and evaluated using various LCD types.
4. closing the life cycle of LCDs. The main result of this WP consisted in the development of guidelines for sustainable LCD design, production and recycling. An information platform, which would remain operative after the project completion, was also developed.