Application of reutilization technology to waste from liquid crystal display (LCD) industry

Abstract

This investigation studies the recycling utility of two major waste products from the liquid crystal display (LCD) industry, panel glass and calcium fluoride sludge, which remain after the treatment of waste water. Waste panel glass was mixed with calcium fluoride sludge in various ratios and then subject to conditioning and melting treatment in order to yield glass-ceramics. Heavy metal leaching tests indicated that reductive conditions lowered the heavy metal concentrations in the leachate to an order of magnitude below that in the waste glass and sludge. A 5:5 (wt%) mixture of glass and sludge melted at 1200°C for 60 min achieves a specific gravity, water absorption, unit mass, porosity ratio, and soundness that meet the American Society for Testing and Materials (ASTM) standard for fine aggregates. Therefore, waste panel glass can indeed be efficiently recycled into a useful construction material.

Keywords:

• LCD industry waste
• heavy metal leaching tests
• melting process
• co-melting
• glass-ceramics

Acknowledgments

The authors would like to thank the National Science Council of the Republic of China, Taiwan, for financially supporting this research under Contract No. NSC 96-2221-E-002-057-MY2.