However, a project by the Industry Council for Electronic Equipment Recycling (ICER) not only examined potential applications for CRT glass, but also focused on current and emerging techniques for separating the leaded and unleaded glass contained in CRTs.
The unleaded glass comprises barium/strontium. This is welded to the leaded glass with a lead frit. Other components in TV and monitor CRTs include electron gun, metal mask and deflector coil and the inside of the screen is coated with a mixture of phosphors. As hazardous waste, the disposal of CRT continues to be contentious, not least because of the old computers and televisions that continue to be dumped in developing countries.
Despite EU waste shipment regulations that ban this export, a recent statement from environmental lobby group Friends of the Earth estimates that 2 million computer monitors and 1 million TVs have ended up in some of the worlds poorest countries since January 2002.
Currently, TVs and computer monitors from households are disposed of through civic amenity (CA) sites and TVs can be disposed of through repairers, rental companies and retailers. The ICER report estimates that up to 500,000 TVs are exported for reuse outside the UK each year.
During the course of ICERs research, 35 possible applications for waste CRT glass were identified with five used for in-depth study. The project which ended in March analysed three products made with CRT panel glass, the first being a brick developed by Staffordshire University. Tests showed that the product was suitable for a range of non-engineering applications such as decorative bricks and cladding tiles. According to the report, the manufacturing process has a reduced environmental impact in terms of C02 emissions compared with standard clay bricks and also compares well in terms of cost. While this application has the potential to use significant quantities of the UKs waste CRT panel glass, it is thought that much market research is needed to develop a market for this niche product.
Another highlighted use was in the manufacture of new CRTs. The study stated that there is the potential to use 10% of the UKs total annual arisings of waste CRT glass in the manufacture of new screens in the UK. Demand for waste CRT glass (panel and funnel) across the existing 15 EU member states is said to be between 8% and 10% of estimated arisings and could increase to as much as 20% if it proves technically and commercially feasible to use more than 50% glass cullet in the manufacture of new funnel glass and 30% in new panel glass.
In order for applications of waste CRT glass to be encouraged, there needs to be greater awareness of opportunities. However, there has been little experience of collecting post-consumer TVs and monitors. To optimise recycling, ICER is developing a code of practice for companies that offer to collect CRTs for recycling so that they can achieve ICER accreditation. u