CONTENTS
EXECUTIVE SUMMARY ÉÉÉ2
WHAT IS GLASS? ÉÉÉ4
HOW IS GLASS MADE? ÉÉÉ5
GLASS AS WASTE ÉÉÉ5
THE CHANGING ROLE OF GLASS PACKAGING ÉÉÉ6
WHY RECYCLE GLASS? ÉÉÉ7
WHAT PROGRESS HAS BEEN MADE IN GLASS RECYCLING? ÉÉÉ7
HOW IS GLASS RECYCLED? ÉÉÉ8
PROBLEMS ENCOUNTERED DURING GLASS RECYCLING ÉÉÉ9
FOREIGN MATERIALS ÉÉÉ10
INCOMPATIBLE GLASS TYPES ÉÉÉ11
COLOUR MIXING ÉÉÉ11
THE FUTURE FOR GLASS RECYCLING ÉÉÉ12
GLASS IN AUTOMOBILES ÉÉÉ12
THE ELV DISPOSAL CHAIN ÉÉÉ14
LAMINATED GLASS RECYCLING ÉÉÉ18
IS IT FEASIBLE TO RECYCLE ELV GLASS? ÉÉÉ20
REFERENCES ÉÉÉ21
USEFUL CONTACTS ÉÉÉ21
ABBREVIATIONS
ACORD Automotive Consortium on Recycling and Disposal
CARE Consortium for Automotive Recycling
ELV End of Life Vehicle
FEVE Federation Europeene du Verre dÕEmballage
Kta Thousand tonnes per annum
mta Million tonnes per annum
PET Poly ethylene terephthalate
PVB Poly vinyl butryl
ACKNOWLEDGEMENTS
The author wishes to thank Mr Derek Wilkins (CARE Programme Manager, Rover Group), Mr. Peter Pennells
(Consultant, Pilkington Glass) and Mr. David Richardson (Director, RichardsonÕs Glass) for their constructive
comments.
2
EXECUTIVE SUMMARY
Glass constitutes just one fraction of societiesÕ complex waste stream. Every year the UK alone produces more
than 435 million tonnes of rubbish, only a relatively small proportion of which is glass. About 75% (possibly
1.5 million tonnes/ annum) of the glass waste arises as containers from post-consumer sources. The proportion
contributed by automotive fractions is small (about 0.06 million tonnes).
Glass has been amongst the most successfully recycled components of the municipal waste stream. From
humble beginnings in 1977, when the first Ôbottle bankÕ was opened in the UK, the amount of container glass
recovered annually has risen steadily to over 440,000 tonnes in 1997. At this time, all 436 UK Local
Government Authorities (and many private companies besides) had bottle banks in place, adding up to more
than 22,000 sites. However, the UK still recovered less than 25% of all the waste glass estimated to be
available. Within the EU as a whole, this proportion is currently about 58% (7.5 million tonnes/ annum), with
only Turkey recovering a smaller proportion than the UK. Astonishingly, eight EU member states manage to
recover more than 70% of their post-consumer glass arisings.
The rapid increase in glass recovery rates is, in no small measure, the result of a number of important factors,
including: the technical feasibility of recycling this material; the cost advantage of doing so; the commitment of
the glass industry to accept post-consumer material and to invest in and develop the technology required to
process the material. Never the less, there have been, and continue to be, problems associated with glass
recycling in general. These are primarily due to contamination of the glass by: mixing of incompatible glass
types (such as bottles, window panes, light bulbs and ovenware); mixing of different colours of glass; and the
presence of non-glass ÔinclusionsÕ (especially stones). All of these problems are being addressed by the glass
recycling industry in attempts to improve the quality (and hence value of the recovered material) and to reduce
the rejection rate of unacceptably contaminated loads.
On top of these technical problems, the glass industry is beset by economic and political pressures. The UK
suffers from an acute imbalance in the availability and demand for different colours of waste glass Ð a result of
the preferences of the packing and filling industries and the consumer. In addition, EU-wide legislation on the
recovery of packaging waste, coupled with more efficient material utilisation in the manufacturing process
(ÔlightweightingÕ) and significant reductions in the prices of the virgin raw materials have meant that there is
now a surplus of recovered glass. This has driven down the demand for, and value of, recovered glass, most
notably in the UK wi th regard to green glass.
It is against this backdrop, of market saturation and depressed prices, that the proposed EU Directive,
concerning End of Life Vehicles may impact. This is envisaged to set limits upon the proportion of an ELV that
could be landfilled, and the burden to meet these targets will inevitably fall, in part, upon glass. This is not, by
any means, a predicament unique to glass amongst the ELV materials; most of the other materials that are not
currently recovered during the shredding process (predominantly non-metallics such as plastics) are or will be
subject to the same economic and political pressures. The recovery of ELV glass is much more complicated
than that of post-consumer container glass. The major cost here is the time and labour expended in collecting
the material from a heterogeneous waste origin (bottle bank schemes generally rely upon the public to segregate
the material and pubs/ clubs deal with a largely homogeneous waste stream). Attempts to achieve this by
structured vehicle dismantling would probably be prohibitively expensive. Although the recovery and reutilisation
of manufacturing scrap is well established, the only significant example of post-consumer flat glass
recycling in the UK is that of in-service vehicle windscreen replacement, which is estimated to yield about
15,000 tonnes/ year.
With annual UK ELV arisings of approximately 1.5 million, the 45,000 tonnes/ year of automotive glass
theoretically available would appear to be a relatively small amount, in relation to the UKsÕ overall glass waste
stream. Field studies by CARE, however, suggest that in practice even this level of recovery is unlikely to be
achieved. This figure assumes that ÔscrappedÕ vehicles retain their full complement of glass, and that all of this
is recovered. This clearly is not the case. Many ELVs are accident damaged, some of the glass is sold by the
vehicle dismantlers as replacement parts, and a significant proportion of that remaining (up to 50%) may be lost
using unsophisticated recovery procedures. Bearing in mind that the cullet market is already saturated, and that
future moves are likely to increase this substantially, ELV-derived cullet will have to compete not only with
virgin raw materials but also packaging was te. Under these circumstances, with virgin raw material prices at
about £30/ tonne, cullet prices hovering between £10-£15/ tonne and Packaging Recovery Notes (PRNs, proof
of compliance with the packaging waste regulations) for glass retailing at about the same, there is little scope to
expect ELV-glass recovery to be economically viable in the UK at present.
3
Above and beyond those problems normally associated with container glass re-processing, there is the potential
for significantly higher contamination levels and waste by-product disposal from processing front and rear
vehicle windscreens. Most front and rear glazing is nowadays directly bonded into the vehicle body apertures,
contributing significantly to body shell rigidity. The edges of these wi ndscreens are printed, in order to mask
the presence of the polyurethane adhesives, and protect the adhesive from UV light induced degradation, but
this constitutes a significant potential contaminant in itself. The same is true of the silver heating elements in
rear windscreens. Furthermore, the poly vinyl butryl (PVB) plastic laminate interlayer renders the front
windscreen much more difficult and hence expensive to process. Not only does the glass have to be separated
from the interlayer, but there is currently no market for the residual plastic, which therefore has to be discarded
(entailing further cost). The emergence of a market for this plastic, which as a virgin material is very expensive,
might go some way to offsetting the cost of windscreen recycling.
Very careful consideration will have to be given as to the eventual preferred glass ÔdisposalÕ route. Glass
recycling, where viable, should be promoted but a balance has to be found between recycling and disposal, a
view taken on the grounds of Ôbest practicable environmental optionÕ (BPEO). The technique of life cycle
analysis may play a crucial role in this procedure. The current wide distribution of ELV dismantling facilities in
the UK could alone render the recycling option redundant. The energy usage, pollutant production and cost of
running a fleet of collection vehicles could negate any environmental benefit. Of critical importance is the
development of additional and/ or alternative end uses for the recovered glass. This may aid the economics of
the situation but doesnÕt improve the logistics problem per se. This applies equally to PVB; the BPEO may well
be incineration with energy recovery. Never-the-less exploration of the feasibility of utilising re-extruded
polymer should not be overlooked, and importantly the process should be transparent, otherwise the outcome
might be susceptible to misinterpretation as the influence of Ôvested interestsÕ.
Any cost associated with such developments should, however, not be confined to any single sector (such as the
glass re-processors) but should be spread amongst all the economic operators. Furthermore, this should not
exclude the consumer. It can be argued, with some justification, that Ôthe consumer rulesÕ philosophy is flawed
and just reflects the prevalence of the Ôconsumer societyÕ in which we live. If we, the consumer, want the
benefits of high mobility and freedom of movement, we must be prepared to accept, within reason,
responsibility for the consequences of these activities and of any remedial action (and hence cost) necessary.
This argument extends, of course, to those other facets of automobile usage, such as fuel consumption, exhaust
emissions, air and water pollution and maintenance of the road infrastructure.
Ford Escort Van Mk5, CARE Hulk Standards Trial, Universal Salvage (Paddock Wood), August 1998
4
WHAT IS GLASS?
Glass, as everybody knows, is hard, brittle and
transparent. Although there is no scientific
consensus, glass i
CONTENTS
EXECUTIVE SUMMARY ÉÉÉ2
WHAT IS GLASS? ÉÉÉ4
HOW IS GLASS MADE? ÉÉÉ5
GLASS AS WASTE ÉÉÉ5
THE CHANGING ROLE OF GLASS PACKAGING ÉÉÉ6
WHY RECYCLE GLASS? ÉÉÉ7
WHAT PROGRESS HAS BEEN MADE IN GLASS RECYCLING? ÉÉÉ7
HOW IS GLASS RECYCLED? ÉÉÉ8
PROBLEMS ENCOUNTERED DURING GLASS RECYCLING ÉÉÉ9
FOREIGN MATERIALS ÉÉÉ10
INCOMPATIBLE GLASS TYPES ÉÉÉ11
COLOUR MIXING ÉÉÉ11
THE FUTURE FOR GLASS RECYCLING ÉÉÉ12
GLASS IN AUTOMOBILES ÉÉÉ12
THE ELV DISPOSAL CHAIN ÉÉÉ14
LAMINATED GLASS RECYCLING ÉÉÉ18
IS IT FEASIBLE TO RECYCLE ELV GLASS? ÉÉÉ20
REFERENCES ÉÉÉ21
USEFUL CONTACTS ÉÉÉ21
ABBREVIATIONS
ACORD Automotive Consortium on Recycling and Disposal
CARE Consortium for Automotive Recycling
ELV End of Life Vehicle
FEVE Federation Europeene du Verre dÕEmballage
Kta Thousand tonnes per annum
mta Million tonnes per annum
PET Poly ethylene terephthalate
PVB Poly vinyl butryl
ACKNOWLEDGEMENTS
The author wishes to thank Mr Derek Wilkins (CARE Programme Manager, Rover Group), Mr. Peter Pennells
(Consultant, Pilkington Glass) and Mr. David Richardson (Director, RichardsonÕs Glass) for their constructive
comments.
2
EXECUTIVE SUMMARY
Glass constitutes just one fraction of societiesÕ complex waste stream. Every year the UK alone produces more
than 435 million tonnes of rubbish, only a relatively small proportion of which is glass. About 75% (possibly
1.5 million tonnes/ annum) of the glass waste arises as containers from post-consumer sources. The proportion
contributed by automotive fractions is small (about 0.06 million tonnes).
Glass has been amongst the most successfully recycled components of the municipal waste stream. From
humble beginnings in 1977, when the first Ôbottle bankÕ was opened in the UK, the amount of container glass
recovered annually has risen steadily to over 440,000 tonnes in 1997. At this time, all 436 UK Local
Government Authorities (and many private companies besides) had bottle banks in place, adding up to more
than 22,000 sites. However, the UK still recovered less than 25% of all the waste glass estimated to be
available. Within the EU as a whole, this proportion is currently about 58% (7.5 million tonnes/ annum), with
only Turkey recovering a smaller proportion than the UK. Astonishingly, eight EU member states manage to
recover more than 70% of their post-consumer glass arisings.
The rapid increase in glass recovery rates is, in no small measure, the result of a number of important factors,
including: the technical feasibility of recycling this material; the cost advantage of doing so; the commitment of
the glass industry to accept post-consumer material and to invest in and develop the technology required to
process the material. Never the less, there have been, and continue to be, problems associated with glass
recycling in general. These are primarily due to contamination of the glass by: mixing of incompatible glass
types (such as bottles, window panes, light bulbs and ovenware); mixing of different colours of glass; and the
presence of non-glass ÔinclusionsÕ (especially stones). All of these problems are being addressed by the glass
recycling industry in attempts to improve the quality (and hence value of the recovered material) and to reduce
the rejection rate of unacceptably contaminated loads.
On top of these technical problems, the glass industry is beset by economic and political pressures. The UK
suffers from an acute imbalance in the availability and demand for different colours of waste glass Ð a result of
the preferences of the packing and filling industries and the consumer. In addition, EU-wide legislation on the
recovery of packaging waste, coupled with more efficient material utilisation in the manufacturing process
(ÔlightweightingÕ) and significant reductions in the prices of the virgin raw materials have meant that there is
now a surplus of recovered glass. This has driven down the demand for, and value of, recovered glass, most
notably in the UK wi th regard to green glass.
It is against this backdrop, of market saturation and depressed prices, that the proposed EU Directive,
concerning End of Life Vehicles may impact. This is envisaged to set limits upon the proportion of an ELV that
could be landfilled, and the burden to meet these targets will inevitably fall, in part, upon glass. This is not, by
any means, a predicament unique to glass amongst the ELV materials; most of the other materials that are not
currently recovered during the shredding process (predominantly non-metallics such as plastics) are or will be
subject to the same economic and political pressures. The recovery of ELV glass is much more complicated
than that of post-consumer container glass. The major cost here is the time and labour expended in collecting
the material from a heterogeneous waste origin (bottle bank schemes generally rely upon the public to segregate
the material and pubs/ clubs deal with a largely homogeneous waste stream). Attempts to achieve this by
structured vehicle dismantling would probably be prohibitively expensive. Although the recovery and reutilisation
of manufacturing scrap is well established, the only significant example of post-consumer flat glass
recycling in the UK is that of in-service vehicle windscreen replacement, which is estimated to yield about
15,000 tonnes/ year.
With annual UK ELV arisings of approximately 1.5 million, the 45,000 tonnes/ year of automotive glass
theoretically available would appear to be a relatively small amount, in relation to the UKsÕ overall glass waste
stream. Field studies by CARE, however, suggest that in practice even this level of recovery is unlikely to be
achieved. This figure assumes that ÔscrappedÕ vehicles retain their full complement of glass, and that all of this
is recovered. This clearly is not the case. Many ELVs are accident damaged, some of the glass is sold by the
vehicle dismantlers as replacement parts, and a significant proportion of that remaining (up to 50%) may be lost
using unsophisticated recovery procedures. Bearing in mind that the cullet market is already saturated, and that
future moves are likely to increase this substantially, ELV-derived cullet will have to compete not only with
virgin raw materials but also packaging was te. Under these circumstances, with virgin raw material prices at
about £30/ tonne, cullet prices hovering between £10-£15/ tonne and Packaging Recovery Notes (PRNs, proof
of compliance with the packaging waste regulations) for glass retailing at about the same, there is little scope to
expect ELV-glass recovery to be economically viable in the UK at present.
3
Above and beyond those problems normally associated with container glass re-processing, there is the potential
for significantly higher contamination levels and waste by-product disposal from processing front and rear
vehicle windscreens. Most front and rear glazing is nowadays directly bonded into the vehicle body apertures,
contributing significantly to body shell rigidity. The edges of these wi ndscreens are printed, in order to mask
the presence of the polyurethane adhesives, and protect the adhesive from UV light induced degradation, but
this constitutes a significant potential contaminant in itself. The same is true of the silver heating elements in
rear windscreens. Furthermore, the poly vinyl butryl (PVB) plastic laminate interlayer renders the front
windscreen much more difficult and hence expensive to process. Not only does the glass have to be separated
from the interlayer, but there is currently no market for the residual plastic, which therefore has to be discarded
(entailing further cost). The emergence of a market for this plastic, which as a virgin material is very expensive,
might go some way to offsetting the cost of windscreen recycling.
Very careful consideration will have to be given as to the eventual preferred glass ÔdisposalÕ route. Glass
recycling, where viable, should be promoted but a balance has to be found between recycling and disposal, a
view taken on the grounds of Ôbest practicable environmental optionÕ (BPEO). The technique of life cycle
analysis may play a crucial role in this procedure. The current wide distribution of ELV dismantling facilities in
the UK could alone render the recycling option redundant. The energy usage, pollutant production and cost of
running a fleet of collection vehicles could negate any environmental benefit. Of critical importance is the
development of additional and/ or alternative end uses for the recovered glass. This may aid the economics of
the situation but doesnÕt improve the logistics problem per se. This applies equally to PVB; the BPEO may well
be incineration with energy recovery. Never-the-less exploration of the feasibility of utilising re-extruded
polymer should not be overlooked, and importantly the process should be transparent, otherwise the outcome
might be susceptible to misinterpretation as the influence of Ôvested interestsÕ.
Any cost associated with such developments should, however, not be confined to any single sector (such as the
glass re-processors) but should be spread amongst all the economic operators. Furthermore, this should not
exclude the consumer. It can be argued, with some justification, that Ôthe consumer rulesÕ philosophy is flawed
and just reflects the prevalence of the Ôconsumer societyÕ in which we live. If we, the consumer, want the
benefits of high mobility and freedom of movement, we must be prepared to accept, within reason,
responsibility for the consequences of these activities and of any remedial action (and hence cost) necessary.
This argument extends, of course, to those other facets of automobile usage, such as fuel consumption, exhaust
emissions, air and water pollution and maintenance of the road infrastructure.
Ford Escort Van Mk5, CARE Hulk Standards Trial, Universal Salvage (Paddock Wood), August 1998
4
WHAT IS GLASS?
Glass, as everybody knows, is hard, brittle and
transparent. Although there is no scientific
consensus, glass i
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