It Technology Essay, Research Paper
1.0 INTRODUCTION
A quote from a PC World magazine on “The Digital Future” said, “in the future,
people will live twice as long, computers will die twice as fast” 1. As computer technology
continues to accelerate at an unprecedented rate, information technology (IT) equipment
waste is becoming an increasingly significant portion of the solid waste stream.
Information Technology equipment waste is receiving increased attention for the
following reasons:
? Rapid advances in technology result in IT equipment becoming obsolete at an
increasingly rapid pace. This is resulting in an increase in the rate and quantity of IT
equipment entering the waste stream;
? A piece of IT equipment was, or is typically of high value, both in terms of its
component parts and the equipment itself;
? IT equipment commonly contains toxic materials, which are hazardous if not
managed properly.
This project provides a broad overview of how such products are
handled and to estimate the amounts of these products and materials that will enter the
waste stream in the next few years.
The specific waste streams addressed include:
? personal computers,
? monitors,
? laptop computers,
? peripherals (e.g., printers, scanners),
2.0 WASTE ESTIMATES FOR IT EQUIPMENT
This section will address the generation and flow of computer equipment waste
from both residential and IC&I sources in Canada. The types of computer equipment
addressed in this project and discussed in this section include:
- Computers (personal computers, servers);
- Monitors;
- Laptop computers;
- Printers;
- Note-pads/note-books, and;
- Peripherals (scanners, modems, keyboards etc.).
The flow of computer equipment in the solid waste stream will require increasing
attention in the future for the following reasons:
- The decreasing lifespan of IT products and their increasing annual sales,
resulting in greater discards of computer equipment waste on an annual basis;
- The mixed composition of computer equipment (i.e., metals, plastics, glass),
which makes dismantling and recycling challenging;
- The presence of hazardous materials; and,
- The life cycle ecological burden represented by waste IT equipment.
Computer equipment can become obsolete as a result of technological
advancements, for example:
- Increasing micro processing speed – from 80386 to 80486 to Pentium I, II and
now III generation systems;
- Increasing memory capacity to support faster microprocessors and expanded
storage requirements;
- Internet developments that cannot be accessed using older systems;
- New and expanding operating systems and software that cannot run on older
systems;
- Advancements in color, resolution and technology for monitors (i.e., flat panel
monitors);
- Increasing speed and color performance for laser and ink-jet printers, and
- Merging technologies such as “all-in-one” equipment, with faxing, printing and
scanning capabilities provided in one unit.
These factors have reduced both the average first life and total lifespan of
computer equipment – where first life refers to the amount of time a product is useful to
its original owner and total lifespan is the period from manufacture to disposal 2.
Computer equipment sales are projected to continue to grow as a result of
decreasing lifespan and the increased use of computers in businesses, institutions and
at home.
The largest growth in computer sales is into the residential market. In 1998 there
were 1.9 million computers installed in Canadian homes and in 2000, there were 2.2
million – an increase of 16%. In the education sector, installed computers increased by
9% in 1999, to 1.4 million. Installed computers in the business sector increased from 6.2
million in 1999 to 7.0 million in 2000 – an increase of 13% 3.
Figure 2-1 presents a simplified schematic of the lifespan of computer equipment
from point of sale, through use, to end of first life, to diversion (reuse and recycling) and
to disposal.
3.0 IT Waste Generation
Each year millions of new computers, monitors, laptops and peripherals are sold
into the Canadian marketplace. Some of these sales represent ‘new’
customers(Businesses, Institutions, Homes, Government offices) who are purchasing
computer equipment for the first time, while the majority are those that are replacing old
or out dated equipment found in residential, commercial and institutional settings. The
obsolete equipment is typically 3-5 years old 4 and, while often still usable (i.e., not
broken), it no longer meets the needs of the user. The point at which a computer
becomes obsolete is also referred to as the end of the equipment’s first life.
Obsolete computer equipment will be directed to one of four destinations/outlets:
1) Storage, 2) Reuse, 3) Recycling, 4) Disposal. (as shown in figure below)
Storage:
In many instances, discarded computer equipment is placed in storage. For
residential computers this may mean storage in basements, or for business computers
this may mean placement in storage or warehousing areas. In many cases IT
equipment is stored largely because the owner hopes that the out-dated equipment has
some potential resale value, or that they may use it in the future. In other cases,
equipment is stored simply because people do not know what to do with it and are
resistant to throwing out a piece of equipment that may have cost them thousands of
dollars a few years ago. Accurate quantification of the number of computers being
stored is not available, but estimates range from 45% to 50% of obsolete computers 5.
Eventually, stored computers will end up being disposed.
Reuse:
End of first-life computer equipment typically goes to one of two reuse
applications: 1) resold as used equipment, or 2) donated to a charity organization.
Retail outlets, both traditional and Internet-based are increasingly becoming avenues for
the sale of used computer equipment. IT manufacturers are also getting into the
business of selling used equipment.
Used IT equipment that retains some useful value will likely be resold into the
secondary computer market under the following scenarios:
- When businesses sell or auction IT equipment into the secondary market for
resale through retail outlets as used computers or for computer parts and
components (e.g., hard drives, motors/fans, CPU’s etc.), and
- End-of-lease IT equipment that is returned to the leasing company at the end of
a two or three year lease is typically sold or auctioned by the leasing company
to secondary computer companies and brokers.
A smaller percentage of used business IT equipment is often sold to employees
for personal use. With the rapid development of computer technology, this option is
diminishing. Computer equipment and dismantled components can be reused and resold
through a variety of outlets, including:
- Cascading or informal distribution of a computer within a company or within a
family;
- Through private resale companies that purchase used equipment in order to
refurbish and resell computer equipment for a profit in local or foreign markets;
- The sale of component parts that have been dismantled by primary recyclers;
- The redistribution of donated equipment (nationally or internationally) through
nonprofit organizations, sometimes in partnership with other companies that can
refurbish equipment.
Recycling:
The recycling infrastructure for computer equipment includes a mix of
primary and secondary recyclers and metal smelting facilities. Typically, primary
recyclers refurbish equipment for resale where possible and dismantle and sort the
remaining equipment into component parts, such as circuit boards, CRT’s (cathode ray
tubes), plastic housing and wires. Sorted materials are then sold to secondary
recyclers or smelters for further processing, or are sent to disposal outlets. Primary
recyclers rely mainly on manual labor for refurbishing and dismantling, although some
mechanical and automated systems are now available.
Secondary recyclers process metals, plastics and glass contained in the IT
equipment to recover raw materials. These recyclers generally use highly automated
processing equipment, requiring minimal manual disassembly.
Electronic and computer waste can also be processed at smelting facilities to
recover precious metals. The pyrometallurgical process utilized at a smelting facility
involves the melting and fusing of ores to separate metallic constituents, such as lead or
copper.
Smelters can also use the leaded glass contained in CRTs as a fluxing agent in
the production of pure lead 7. Noranda’s Horne facility in northwestern Quebec is the
largest North American copper and precious metal smelter 6.
CRTs require special processing because they can contain from 0.7 to 2.7 kg of
lead depending on the monitor size and year of manufacture. Monitors that can not be
refurbished can be recycled into new CRTs or used as fluxing agents by a secondary
lead smelter. To reuse an old CRT in the manufacture of a new CRT, the face glass is
separated from the neck and funnel glass and the frit bonding compound by sawing the
CRT at the frit bonding compound. If the CRT glass is to be used as a fluxing agent it
does not require separation. The glass can be recovered in this process as well 7.
Disposal:
IT equipment as a whole or as its dismantled component parts can be
disposed in landfills or incinerators. At this time, there is limited information available
on the percentage of the waste stream that is made up of IT equipment. A 1999 waste
composition study in the City of Calgary found that electronic equipment (including
computers, radios, televisions etc.) comprised 1.2% of the residential waste stream or
3,000 tons per year 8. This is comparable to US solid waste data that shows that
electronic waste comprises 1-2% of the solid waste stream 9. Equivalent information is
not available for IC&I waste at this time but could form the focus of future studies.
The projected trend of estimated quantities of Information technology waste disposed
from 1999 to 2005 is given below :
Projections for the flow of IT equipment and storage patterns can be further refined
as more recovery information becomes available regarding quantities of computer
equipment that are reused and recycled in Canada.
The waste flow estimates for various pieces of computer equipment are presented in the following tables:
- Table 2-2– Personal Computers
- Table 2-3– Monitors
- Table 2-4– Laptop Computers
- Table 2-5– Peripherals
Based on the Waste Flow Tool, it is estimated that in 2000, approximately 33,972
tons of IT equipment waste (including PCs monitors, laptops and peripherals) was
disposed, 15,592 tons was recycled, 24,507 tons was sent for reuse and 6,128 was
put into storage. Some pieces of IT equipment which had been stored or reused in
previous years entered the waste stream in 2000. Of the IT waste disposed, PCs and
servers accounted for an estimated 10,833 tons, monitors accounted for an estimated
10,688 tons, peripherals (scanners, printers, etc) accounted for about 11,474 tons and
laptops accounted for about 977 tons. In 2005, the Waste Flow Tools predict that
approximately 67,324 tons of IT equipment waste (including PCs monitors, laptops and
peripherals, but excluding mainframes and other large equipment) will be disposed,
47,791 tons will be reused, 11,948 tons will be stored and 43,428 tons will be recycled.
Of the total IT waste that will be disposed, PCs and servers will account for an estimated
23,349 tons, monitors will account for an estimated 24,472 tons, peripherals (scanners,
printers, etc) will account for about 17,396 tons and laptops will account for about 2,107
tons.
Note:
The quantities disposed, recycled, stored and reused do not add to the amount of
IT equipment that became obsolete in 2000 because a portion of IT equipment from
storage and reuse from earlier years enters the IT equipment waste flow in 2000.
4.0 Materials Contained in IT Equipment
The challenge encountered in diverting computers and peripherals from the
waste stream through recycling and refurbishing activity result from the diversity of
products and variety of materials contained in each product. For example, each hard
drive contains a range of metals and plastics that can be difficult to separate. It is also
difficult to identify the different plastics contained in each piece of equipment by resin
type.
The composition of personal computers and monitors are given in the Table 2 – 7
and the chart below:
? Precious metals include nickel, manganese, cobalt, barium, tin,
silver, antimony, chromium, cadmium, selenium, mercury, gold and
arsenic.
Many of the materials contained in IT equipment can be potentially hazardous if
improperly managed. For example, printed circuit boards contain heavy metals such as
antimony, silver, chromium, zinc, lead, tin and copper and a CRT in a computer monitor
can contain from 0.7 to 2.7 kg of lead depending on the monitor’s size and year of
manufacture 10.
The production of semiconductors, printed circuit boards, disk drives and
monitors use a number of hazardous materials 11. The lead oxide used in the cathode
ray tubes (CRT) of computer monitors is of particular concern and it has been estimated
that computer monitors represent approximately 15% of the lead found in the municipal
waste stream 12.
Hazardous materials found in obsolete computer equipment can be released to
the environment through the following pathways:
- Incineration of computer equipment concentrates heavy metals in ash residue;
- Landfill disposal of computer equipment, and;
- Recycling and recovery of computer equipment waste.
The estimated quantities of materials contained in disposed PC’s and monitors in
Canada in 1999 and in 2005 are shown in table and chart below:
The hazardous materials contained in computer equipment that are of greatest
concern are summarized below.
Lead
Lead is found in the CRT, in the soldering of printed circuit boards and in other
components of IT equipment. Lead represents approximately 6.3%, by weight of an
average PC 13. Based on the total number of obsolete PC’s and monitors in Canada in
2000, this translates to about 1,356 tons of lead disposed in 2000.
Based on the prediction that 47,821 tons of PCs and monitors will be disposed
in 2005 and assuming that the average composition of this equipment will not change
significantly by that year, 3,012 tons of lead will be disposed with this stream in 2005.
A CRT in a computer monitor can contain from 0.7 to 2.7 kg of lead depending on the
monitors size and year of manufacture. This lead is contained in various components of
the CRT, including: 14
? The glass funnel, which is glass that is 22-25% lead (bound into the glass). Lead
is used in the funnel to shield users from radiation produced by the electron gun.
? The faceplate, which contains 2-3% lead bound into the glass.
? The frit (a glass solder that joins the faceplate and funnel components of the
CRT), which contains 15 to 100 grams per CRT.
The lead contained in the frit is of greater concern because it is in a soluble form
(primarily lead oxide) that can leach 15, while the lead contained in the glass funnel and
in the faceplate is in an insoluble form.
Cadmium
Cadmium is present in certain components, including chip resistors, infrared
detectors, semiconductors, older CRTs and is sometimes present in plastics as a
stabilizer. Cadmium represents approximately 0.009% of a PC by weight 16. Based on
the total number of disposed PC’s in Canada in 2000, this translates to 2.0 tons of
cadmium.
Based on the prediction that 47,821 tones of PCs and monitors will be disposed
in 2005 and assuming that the average composition of this equipment will not change
significantly by that year, 4.5 tons of cadmium will be disposed with this stream in 2005.
Mercury
Mercury is used in printed circuit boards, batteries, switches and printed wiring
boards. While the percentage found in the average PC is only 0.002%, 17 based on the
total number of disposed PCs estimated in Canada in 2000, this represents 0.5 tons of
mercury. Mercury is also found in the fluorescent lamps that were previously used to
backlight laptop computer screens, but have now been replaced with xenon.
Based on the prediction that 47,821 tons of PCs and monitors will be disposed in
2005 and assuming that the average composition of this equipment will not change
significantly by that year, 1.1 tons of mercury will be disposed with this stream in
2005.
Brominated Flame Retardants
Brominated flame retardants are used to reduce the flammability of plastics in
electronic products. They are most typically used in circuit boards, connectors, plastic
covers and cables 18. There are many types of BFRs (more than 60), some of which are
more toxic than others. The European Union Waste Electrical and Electronic Equipment
(WEEE) Directive has chosen to focus its efforts on the two classes of BFRs that pose
the highest cause for concern, that is, polybrominated biphenyls (PBB) and
polybrominated diphenyl ethers (PBDE). These are the compounds that are most likely
to form dioxins and furans during the incineration process. When these compounds are
burned, brominated materials are converted into polybrominated dibenzo furans (PBDF)
and polybrominated dibenzo dioxins (PBDD) and can be released into the atmosphere.19
Therefore, when plastics containing BFRs, in particular PBB and PBDE, are
extruded during the recycling process or when they are incinerated for disposal,
hazardous compounds may be released into the environment.
Polyvinyl Chloride Plastic (PVC)
Although most computer moldings are now made using ABS plastic, PVC has
been widely used in computer cabling and housings. There is a risk that dioxins and
furans will be formed when PVC is incinerated. In addition, PVC is a difficult plastic to
recycle if mixed with styrenics and contaminates other plastics (e.g., PET) in the
recycling process.
5.0 IT Equipment Design Changes to Reduce Toxicity and Facilitate Recycling
Many manufactures are attempting to eliminate substances of concern from their
products, including, lead, arsenic, brominated flame retardants, cadmium, hexavalent
chromium, mercury and PVC. Examples are provided below.
Hewlett-Packard’s Office Jet 500 multi-purpose printer uses a metal chassis and
power supply enclosure to eliminate the need for flame retardants and light emitting
diodes (LED’s) instead of a mercury lamp for the scanner, and eliminates the need for
batteries by using flash memory technology.
The primary plastic resin used in Intel’s PCs and servers (ABS and
polycarbonate) does not use flame retardants that contain PBBs or PBDEs.
None of their products contain asbestos, or include lead or cadmium as plastic
additives. 20
Philips Consumer Electronics evaluate all of its products against their list of
banned substances (asbestos, cadmium, mercury, CFC/HCFC, PCP, PCB, PCT,
PBB/PBBE) before their introduction. 21
Motorola conducts research with their suppliers of printed wiring board laminates,
plastics, and electronic components to replace lead and BFRs. 22
Panasonic has identified 37 substances of concern in their manufacturing
process with 13 targeted for elimination and the remaining 24 for reduction. 23
Sony Corporation is developing a non-lead based solder for some products and
seeks to eliminate dioxin forming compounds through design guidelines. 24
Toshiba has introduced the Satellite 2520 notebook with a halogen-free
motherboard and plans to switch over to halogen-free boards for the entire PC
product range by the end of 2001. 25
Digital’s (now Compaq) Corporate Regulated Material Specification includes the
banning of PBBs, PBBOs and PBBEs. Numerous other halogenated compounds
are listed in this specification including the 25 halogenated dioxins and furans,
which are restricted by the German Dioxin Ordinance.
As a part of Sony’s Green Management 2002 Plan, they will eliminate the use of
halogenated flame retardants in all European models by 2001 and in all models
by 2002.
Many manufacturers are improving the recyclability of their products by
incorporating recyclable materials into products, by making their products easier to
dismantle and by marking the various materials contained in the equipment, for example:
Plastic components of Apple products that are greater than 100 grams are made
from the same type of plastic material;
Apple designs its product with latches, snap-in connections, and single screw
types requiring no specialized tools;
Hewlett Packard designs many of its products so that they are easier to take
apart; many components simply snap apart, making it easier to separate metal
from the plastic;
IBM’s DfE (Design for the Environment) guidelines encourage the use of snap fits
instead of fasteners, and where fasteners are used, they use a minimum number of
standard sizes that do not require special tools when dismantling, and Intel’s product
design checklist encourages ease of disassembly and appropriate materials choice.
6.0 Future Trends in IT Technology
The IT sectors are converging at a rapid rate and with the development of fibre-
optic networks, data, sound and video will be accessible at a rapidly expanding rate. It is
challenging to predict the extent to which the future will be different to the present. This
section will describe a number of trends identified through the literature review and survey
carried out for this study, but will not attempt to estimate the potential impacts of these
trends because of the significant uncertainty involved.
General Trends
Moore’s Law, based on a 1965 prediction by Intel cofounder Gordon Moore,
states that processing power will double every 18 months. This has been the case since
the early 1970’s and it is not expected to change even ten years from now 26. Recent
advancements in wireless phone and notepad/Palm organizers have resulted in
predictions of the demise of the PC.
Rumors of the PC’s demise may be premature, but they aren’t necessarily
exaggerated. No one can say for certain whether the PC will survive the coming
onslaught of super smart alternative computing devices ranging from wireless phones to
household appliances. Such products could make the PC less essential. In short, you
can expect PC to become smaller and more powerful, with thinner and lighter screens,
and advances in voice recognition could ultimately make your mouse and keyboard a
museum piece. But while the aging PC may undergo some cosmetic nips and tucks, it
probably won’t disappear altogether – at least not in the near future. 27
There is a new trend away from PC’s to NC’s (network computers) in the
workplace and for networks data to be contained on the Internet rather than on a
computer based network server. This approach means that the computers on people’s
desks at work will not have hard drives, which will all be located on one server. Units of
hardware, such as monitors and keypads are predicted to last at least ten years, and the
server will be upgraded only as needed. This approach will significantly reduce computer
system maintenance requirements. Also, from this study’s point of view, the size of
equipment involved – a small desktop NC – will be considerably smaller than existing
PCs, and the rate at which these units will be discarded may be slower than for current
technology, thus reducing the flow of IT waste to disposal.
7.0 Technology Changes in Computer Equipment
Flat panel displays (FPDs) such as plasma display panels and liquid crystal
displays (LCD) offer several environmental advantages over CRTs, including reduced
Weight volume, energy consumption and lead content. Lifecycle analysis and recycling
of FPDs is being researched at the University of Tennessee. It should be noted that
while FPDs do not contain leaded glass, they do contain levels of mercury that are
comparable to fluorescent lights 28. While FPDs are currently available, they are
prohibitively expensive for many users. FPDs are expected to be priced more
competitively in 2003, but will still be more expensive than CRTs. 29
Many manufacturers are also attempting to design their equipment to facilitate
upgrading. For example, IBM Printing Systems Company’s InfoPrint 3900/4000 printer
engine has been upgraded 19 times since 1990, enabling customers to upgrade their
equipment rather than dispose of it. 30
Another example of advancements in computer technology is the development of
one machine with printing, faxing, scanning and copying capabilities. The development
of these comprehensive machines will replace the need for four separate pieces of
equipment with one, at a lower or comparable price. This may result in a significantly
reduced amount of waste IT equipment at the end of its useful life.
Given the rapid technological advancements and the reducing “lag time” or
lifespan of computer equipment, it will be challenging for waste management planners
and policy makers to keep pace.
Corporate Environmental Developments
Worldwide trends in corporate environmental programs such as ISO 14001, EMS
and Extended Producer Responsibility (EPR) are beginning to impact computer
manufacturers in North America. Design for the Environment (DfE) programs at IBM,
Apple and Compaq are addressing issues such as eliminating brominated flame
retardants (BFR) in plastics, finding alternatives to lead for circuit board solder, and
labeling of plastics to aid in dismantling.
8.0 IT EQUIPMENT REUSE AND RECYCLING ACTIVITIES IN CANADA
The IT equipment reuse and recycling infrastructure in Canada is far from
uniform and has limited coverage. It is an immature business, with a relatively small
number of companies across the country, but the numbers are growing. It is expected
that the demand for this type of service will continue to grow as increasing quantities of
IT waste enter the waste stream in future years.
That said, there are already a number of IT equipment waste reuse and recycling
companies across Canada. Most companies try to refurbish viable IT equipment where
possible, as this generates the highest revenue per unit. Units which can not be
repaired, upgraded or sold, are manually dismantled by most recycling companies, who
sort the IT equipment into its various components (sometimes into 40 separate
categories) in order to get the highest market price for high quality material streams such
as wire, circuit boards, power bars, semi-precious and base metals, etc. There are also
some automated computer recycling companies that provide secure destruction services
for information contained on hard drives, that also recycle component materials. Many
companies who recycle IT equipment also handle telecom equipment.
9.0 CONCLUSIONS
This preliminary baseline study estimated that approximately 33,972 tons of IT
waste were disposed in Canada in 2000. This number is expected to rise as IT
technology continues to develop at its currently rapid pace, and IT equipment faces
continuous redesign and shorter life spans. It is assumed that a significant amount of
this waste is currently in storage, because people and businesses are unsure of what to
do with it.
Throughout Canada, both residential and commercial IT waste generators are
willing to recycle or reuse this equipment, but do not know how to go about doing this. A
directory of all the options available across the country would help considerably to
increase recovery of this waste stream, as people are reluctant to dispose of equipment
which cost a lot of money a few years ago.
The infrastructure to reuse and recycle IT waste is relatively undeveloped in
Canada at this time, but is beginning to develop at a rapid pace. As an example of this
growth, there were 4 companies in Western Canada until recently who dealt with the
recycling of IT waste, but this number has grown to about 25 this year, with increasing
need for this type of service. The Canadian infrastructure is considerably less developed
than in the US, in part due to our geography and smaller population. The capacity for
handling CRTs is particularly low, as it is globally. While processing capabilities are in
place, industry has not expressed an interest in conducting a take-back program similar
to those operating in the UK or Sweden. IT waste presents a number of challenges
because of the complex combination of materials involved (specialized plastics and
precious metals). Technologies are available to effectively refurbish and recycle this
equipment, therefore many options to disposal are available. Trends in the IT business
include a focus on designing IT equipment to facilitate easier dismantling, and a focus on
identifying options to recycle CRTs. Recycling and refurbishing of CRT’s is less
developed than for other equipment.
The IT business in Canada is characterized by numerous suppliers and agents,
but relatively little manufacturing directly in Canada. Any manufacturing by large IT
companies is carried out in the US or overseas. A number of companies were sending a
considerable amount of equipment to China. This market was closed to overseas outlets
on 1 April, 2000, which may have significant impacts on a number of the companies in
Canada who deal with this waste.
At a future date, a complete listing of all companies and organizations in Canada
who deal with IT waste should be developed, and a comprehensive survey
of all of these companies should be carried out to identify their current operations and
capacity and any barriers to increased recovery.
Leased IT equipment is easier to recover than purchased equipment, because of
the relatively limited number of suppliers involved, and the relatively easy recovery
mechanism. At this time, an estimated 75% of IT equipment in Canada is purchased
rather than leased, therefore this is the predominant pathway which needs to be
disaggregated as much as possible. Also, recovery options are different for IT equipment
generated by households, compared to businesses, therefore at a minimum, a split
between residential and commercial IT equipment owners needs to be identified.
Bibliography
REFERENCES
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