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It is estimated that 2.4 million tonnes per year of glass containers
enter the waste stream, of which 30% is recovered and recycled in
the UK. The remainder goes to landfill. The majority of the recovered
glass is re-melted and formed into new bottles and containers for
the food industry. There are currently 150,000 tonnes per year of
recovered waste glass containers that are available for use in alternative
applications. |
| It has been predicted that by 2006, with an increased recovery level
of waste glass containers, there could be a surplus of at least
600,000 tonnes per year that is unsuitable for glass container manufacture
due to colour or quality. Alternative applications therefore need
to be developed. |
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| What
are these alternative applications? |
Aggregates
Waste glass is used as a substitute aggregate for several applications
such as general backfill, non-structural concrete product and bound
road sub-surface layers. All of these applications have the potential
to be high volume, low cost markets. A product known as 'Glasphalt',
which is a road sub-surface layer, has been developed and successfully
used by RMC. Glass has the advantage of being free draining when used
as a general fill material and, when added to concrete can increase
its strength. |
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Shot
blast abrasives
Glass grit is an ideal substitute for traditional abrasives such
as sand or copper slag for onsite cleaning and removal of rust,
paint or graffiti. Glass has the advantage that it contains less
than 1% crystalline silica (airborne crystalline |
silica can cause
silicosis) and contains no toxic compounds that are commonly found
in copper slag. It has been reported that glass grit has better
performance than copper slag and when used in a wet blast system,
cleaning becomes more efficient as there is no need to use a solvent
pre-treatment.
This application could potentially consume between 50,000 and 100,000
tonnes per year of waste glass at an average £70 per tonne.
This is roughly the same cost as copper slag. |
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Filtration
Glass sand has the potential to replace silica sand in water filtration
systems for potable water and wastewater. This use is still undergoing
trials, however the market potential could be as high as 250,000 tonnes
per year, replacing the need for virgin sand.
Bacteria and other deposits do not adhere to glass sand like they do
with silica sand so it is easily cleaned during the backwashing process.
It is reported that this property can increase the life of the filtration
system. Due to its high specification, grading and cleaning, filtration
silica sands can cost between £50 and £150 per tonne.
Decorative
Applications
There is a developing niche market for products made from recycled glass
such as paving tiles, worktops, tableware, ornaments, and decorative
aggregates. This market tends to require clean and colour separated
glass. The waste glass requirement is relatively small, less than 3,000
tonnes per year, but most of these products tend to be high value due
to the labour intensive manufacturing processes used. |
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Fibre
glass production
The manufacturers of insulation fibre have traditionally used flat
glass cullet as it uses contains fewer contaminants. However, through
the Packaging Waste Recovery Notes compliance scheme it is becoming
financially attractive to use recycled container cullet if it is
processed to an acceptable specification. It is predicted that this
sector could consume an additional 17,000 tonnes per year.
Incentives
to recycle glass
Under the Government's waste packaging compliance scheme there
is a financial incentive to use more waste glass containers, either
in primary manufacture or alternative markets through the use
of Packaging Recovery Notes. |
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| Glass Fact Sheet : |
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