Post on 04-Jan-2016
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“The information age’s toxic garbage”
A review of electronic waste (e-waste)
recycling technologies
“Is e-waste an opportunity or treat?”
Prof.Dr. Muammer KayaEskişehir-Osmangazi University
Technological Research Center (TEKAM)Eskişehir-TURKEY
WHAT IS e-WASTE? (Discarded/EOL electronics)
• Since the 1980’s, with the development of consumer-oriented electrical and electronic technologies, countless units of electric and electronic equipment (EEE) have been sold to the consumer.
When electronic products become obsolete and are ready for disposal, they are known as e-waste.
Whether generated at home/office, e-waste is most rapidly growing waste problem in the world (20-50 million t/y (UN))
Information technology and electronic industry are the world’s largest and fastest growing manufacturing industries.
But to date, industry, government and consumers have only taken small steps to deal with this looming problem.
Developed countries that use most of the world’s electronic products, generate most of the e-waste, and tried to solve this problem by exporting hazardous e-waste to the poor countries in Asia and Africa.
E-waste is the inevitable product of a technological revolution.As a consequences of this alarming growth, combined with rapid product obsolescence, discarded
WEEE CLASSIFICATION OF e-WASTE (2003)WEEE Category Rate of Recovery Rate of Reuse
& Recycling
1. Large household appliances (ovens, refrigerators, driers, washing machines, air conditioners etc.)
80% 75%
2. Small household appliances (toasters, vacuum cleaners, mixers, ovens etc.)
70% 50%
3. IT& telecommunication appliances (PCs, desk tops, lap tops, printers, phones, scanners, mouses, faxes, photocopy machines, computer peripherals, wireless devices etc.)
75% 65%
4. Consumer equipments electronics (TVs, flat panels, plasmas, LCDs, HiFis, portable CD players, DVDs, VCDs, iPods, MP3s, PDAs etc.)
75% 65%
5. Lighting equipments (mainly fluorescent tubes/ bulbs) (gas discharge lamp 80%)
70% 50%
6. Electrical and electronic tools (E-tools) (drilling machines, electric lawnmowers etc.)
70% 50%
7. Toys, leisure & sports equipments (electronic toys training machines etc.)
70% 50%
8. Medical devices (X-Ray, MRI, EKG, SEM, Microscopes etc)
To be established by end of 2008
9. Monitoring and control instruments (Lasers, GPRS etc)
70% 50%
10. Automatic dispensers (ticket issuing, vending machines automats etc.)
80% 75%
EU-27 E-waste amount was 8.3 million t in 2005 E-waste amount will be 10 million t in 2011
collected 2.2 million t collected 5.3 million t
WHY e-WASTE IS A PROBLEM?
• Serious problem not only quantity but also toxic ingredients (such as Pb, Hg, Cd, Cr, brominated flame retardants (BFR)) which create occupational and environmental health threats and hazards.
• E-waste contains over 1000 different substances many of them are toxic and creates serious pollution problems upon landfilling/burning.
• Life span of EEEs is shrinking&obsolescence rate is increasing.• Replacement of EEE’s are easier/cheaper than repair them.
e-WASTE DISPOSAL METHODS(BASEL CONVENTION bans the transport/export of hazardous material from rich to poor
countries and 170 countries signed the convention)
CONVENTIONAL (Cheap but not environment friendly
(contaminate ground water, soil and air)
I. LANDFILL (contaminate ground water)
II. STABILIZING (requires pretreatment and expensive)
III. INCINERATION/BURNING (releases metals/ashes/gases)
IV. EXPORTING TO THE POOR COUNTRIES (cheap, easy)
(Disposal of e-waste to the MSW is prohibited today)
NEW WASTE MANAGEMENT OPTIONS/TECHNOLOGIES
(expensive but environment friendly)
I. RECOVERY (collection, sorting)II. REUSE (resell, second-hand use)III. RECYCLING (valuable materials are
recovered by hydro, pyro and electro metallurgical methods)
* example: Umicore (recycled 1% of cellphones in the world in 2006)
Financement:
- Advanced Recycling Fee (ARF): (Swico) (consumer pay 7-30 $)
- Extended Producer Responsibility (EPR) TakeBack (GreenPhone, Collective Goods)
- Tax Incentives (Credit)
SOME FACTS ABOUT e-WASTE IN THE WORLD
• According to EPA, yearly e-waste produced in the USA is estimated 5-7 million tons. Only 20% of these are recycled, 30% or more stored 3-5 years for future disposal and the rest is land filled/exported.
• E-waste constitutes from 3-8% of the U.S.-MSW and is growing rapidly.• Approximately 25 million TV sets and 50 million computer monitors are sold in the USA
annually. According to EPA, yearly 30-40 million PC become obsolete in the U.S.• Computer industry brings new technology on market every 18 months. Conventional TV
sets will be replaced by HD TV’s (25 million TV/year) which will put millions of kilos of CRT Pb (leaded glass) into environment.
• In the USA, Americans own about 2 billion electronic devices or 25 per household.• 130 million cell phones are retired each year in the USA. Yearly 3 billion batteries and 80
million automotive batteries are sold in the USA.• In 1999, only 11-15% of discarded computers are recycled compared with 70% of the
major appliances (refrigerators, washing machines, dryers etc) and 28% of overall MSW.• In the USA, btw 50% and 80% of collected e-waste for recycling are not recycled domes-
tically at all; but, shipped to poor countries (China, India, Nigeria, Ghana, Ivery Coast, Lagos etc.).
• In Europe, the volume of e-waste is raising 3-5% annually almost three times faster than the MSW.
• In EU, 6.5 million tonnes of e-waste generated annually. The battery consumption per person is about 10 in Europe.
• E-WASTE MARKET generated $7.2 billion in 2007 and will be expected to generate $11 billion in 2009 (Yearly growth: 5-8%).
HAZARDOUS MATERIALS IN THE e-WASTE(Electronic products/components contain, chlorinated solvents, BFR, PVC, heavy metals, plastics and
glasses)
• Computer circuit boards: Pb, Cd• Computer batteries, semi conductors: Cd, Ni• Printed circuit boards, cables and plastic
casings: BFRs, Sb2O3, PVC (when burned releases toxic furans and dioxins)
• Switches, flat screens, housing: Hg• Old capacitors/transformators: PCBs• CRT glass: Pb (%25), Ba, As• Power suppy: Se• Stell parts: Cr (corrosion), Co (magnetivity)
Lead (Pb): cause damage to the nervous and blood systems and kidney in humans, accumulates in the environment, and has acute and chronic toxic effects on plants, animals and microorganisms. Children suffer developmental effects and loss of mental/brain ability, even at low levels of exposure.
Consumer electronics constitute 40% Pb found in landfills. The main concern in regard to the presence of Pb in landfills is the potential for the Pb to leach and contaminate drinking water supplies. The main applications of Pb in electronics are soldering of printed circuit boards and other electronic components and CRTs.
Composition of a personal desktop computer based on a typical desktop computer, weighting ~70lbs
Name
Content (% of total weight)
Recycling Efficiency Use/Location
plastics 22.9907 20% includes organics, oxides other than silica
lead 6.2988 5% metal joining, radiation shield/CRT, PWB
aluminum 14.1723 80% structural, conductivity/housing, CRT, PWB, connectors
germanium 0.0016 0% semiconductor/PWB
gallium 0.0013 0% semiconductor/PWB
iron 20.4712 80% structural, magnetivity/(steel) housing,CRT, PWB
tin 1.0078 70% metal joining/PWB, CRT
copper 6.9287 90% conductivity/CRT, PWB, connectors
barium 0.0315 0% getter in vacuum tube/CRT
nickel 0.8503 80% structural, magnetivity/(steel) housing,CRT, PWB
zinc 2.2046 60% battery, phosphor emitter/PWB, CRT
tantalum 0.0157 0% capacitors/PWB, power supply
indium 0.0016 60% transistor, rectifiers/PWB
vanadium 0.0002 0% red phosphor emitter/CRT
terbium 0 0% green phosphor activator, dopant/CRT,PWB
beryllium 0.0157 0% thermal conductivity/PWB, connectors
gold 0.0016 99% connectivity, conductivity/PWB, connectors
europium 0.0002 0% phosphor activator/PWB
titanium 0.0157 0% pigment, alloying agent/(aluminum) housing
ruthenium 0.0016 80% resistive circuit/PWB
cobalt 0.0157 85% structural, magnetivity/(steel) housing,CRT, PWB
palladium 0.0003 95% connectivity, conductivity/PWB, connectors
manganese 0.0315 0% structural, magnetivity/(steel) housing,CRT, PWB
silver 0.0189 98% conductivity/PWB, connectors
antinomy 0.0094 0% diodes/housing, PWB, CRT
bismuth 0.0063 0% wetting agent in thick film/PWB
chromium 0.0063 0% decorative, hardener/(steel) housing
cadmium 0.0094 0% battery, blu_green phosphor emitter/housing, PWB, CRT
selenium 0.0016 70% rectifiers/PWB
niobium 0.0002 0% welding allow/housing
yttrium 0.0002 0% red phosphor emitter/CRT
rhodium 0 50% thick film conductor/PWB
platinum 0 95% thick film conductor/PWB
mercury 0.0022 0% batteries, switches/housing, PWB
arsenic 0.0013 0% doping agents in transistors/PWB
silica 24.8803 0% glass, solid state devices/CRT,PWB
The EU’s Waste Electrical and Electronic Equipment (WEEE)
and Restriction of Hazardous Substances (RoHS) Directives
The WEEE Directive requires that producer is responsible for the treatment of WEEE. The directive also requires labeling of e-waste identifying the different components and materials within those components.
The RoHS takes prevention a step further by phasing out the use
of hazardous substances in the production of EEEs by 2008. Hazardous Material Limits (%) at
WEEE according to RoHS Directive
Cadmium 0.01
Lead 0.1
Mercury 0.1
Hex. Cr 0.1
PBB 0.1
PBDE 0.1
FLOWSHEET OF e-WASTE RECYCLING
COLLECTION: Permanent, special drop-off and curbside metods.
TRANSPORTATION: to the recyclers by customers, municipalities or recyclers
MATERIALS RECOVERY FACILITY (MFR):
1. Testing and sorting for reuse/resale,2. Manual/mechanical dismantling of
valuable parts from cheap/valueless ones,
3. After removing hazardous substances, valuable materials are recovered by magnetic, gravity, eddy current, flotation separation methods,
4. Hydro/pyro metallurgical smelting& leaching and refining&conditioning,
5. SECONDARY RAW MATERIALS are produced for use.
6. Final waste is disposed by landfilling/ burning.
Test/Sort
CATHODE RAY TUBE (CRT) RECYCLING SOLUTIONS-1(Monitors-Screens-Displays)
• - contain toxic items, - volume is high, - direct disposal restricted.
• - consists of two parts: glass components (funnel, panel, solder glasses and neck) and non-plastic components (plastic, steel, Cu, electron gun, P coating)
• - CRT glass consists of SiO2, Na2O, CaO and other components for coloring, oxidizing and X-rays protection (K2O, MgO, ZnO, BaO and PbO).
• There are two CRT recycling methods: glass-to-glass (GTG) and glass-to-lead (GTL).
•
CATHODE RAY TUBES (CRT) RECYCLING SOLUTIONS-2(CRTs contain 0.5-5 kg Pb in the glass for X-ray protection and 1- 2.3 kg Cu in the yoke)
1. GTG Recycling: Closed loop recycling (from used CRT to new CRT(up to 40%)). Labor intensive and expensive method.
a. Shredding: CRT is ground as a whole into cullets, which are used to make new cullets to replace the virgin material (mixed cullets sold to smelters)
b. Sawing: Panel and funnel glasses can be separeted to avoid contamination (sorted cullets sold to smelters)
(Leaders: Eco-International (2007) (NxTCycle-AZ, Envirocycle-PA (1991), Amandi), Dlubak Glass-Oh/AZ (Largest recycler-10% of US CRTs).
2. GTL Recycling: Automated, cheap, safe, efficient; but, reduces the high-quality of glass
Before smelting, the CRT is shredded, Pb and Cu metals and plastics are separated. Recovered CRT glass goes to the Pb smelter and it behaves as a fluxing agent in the smelting process.
(Ex: Doe Run (World’s largest secondary Pb smelter), Noranda (Xstrata)
Rival to CRT Recycling: 10 times cheaper overseas recycling. Shipping cost is cheap with empty containers to China
CRT Liquid-Crystal Dispays (LCD) and Plasma Screen (Flat Sceen-HDTV)
CATHODE RAY TUBE (CRT) RECYCLING-3(Exporting CRT with containers to Asia is ten times cheaper than recycling in the
USA)
CHINA
S.AFRICA
CRT Glass Processing at DlubakCRT take apart for panel and funnel glass
Panel glass sorting by composition Glass cleaning, crushing, and sorting by size
Ferrous and non-ferrous metal removal Organic contaminant removal
BATTERY RECYCLING
• Hazardous automobile Pb-acid battery recycling ratio is 90% in the U.S..
• In US annually 3 billion, in Germany 31000t in England 20000t and in Turkey 11000 t household batteries are used.
• Household batteries may contain Pb, Zn, Cd, Hg, Ni, As, Mn, Cr etc.
• 88% Hg and 54% Cd, in MSW in the U.S., 10% Zn, 67% Ni and 85% Cd in MSW in Germany come from batteries.
• In EU, 75% of batteries used at home and 95% of batteries used at industry will be collected and recycled soon.
• Recycling of mixed batteries are difficult and present vapor hazards.
• Alkaline, Zn-C, NiCd, Lion, NiMH, mercuric oxide and silver oxide button batteries are recyclable.
• NiCd batteries are more hazardous than NiMH and Lion batteries.
• There are several hydro/pyro metalur-gical processes for battery recycling (Sumitomo, Recytec, Atech, Snam-Savam, Sab-Nife, Inmetco, Waelz, TNO and Accurec etc).
• Recycling fee changes from 300-2000 $/t.• Battery recycling requires a high amount
of energy.
Alkaline and Zn-C Batteries Recycling Flowsheet
Umicore VAL’EAS Battery Recycling Process & Flow Sheet
The VAL’EAS™ process is dedicated to the recycling of rechargeable Lithium ion and Nickel Metal Hydride batteries and battery packs, transforming end of life rechargeable batteries into new batteries.
a melting operation: rechargeable batteries, battery packs and other input materials are injected into a furnace without any pre-processing, minimising all hazardous risks
a preferment gas cleaning of installation equipped with the new plasma technology to make the formation dioxin and furan impossible
well controlled melting conditions so that a clean slag can be produced and further re-used in construction and/or as aggregate for concrete.
a cobalt & nickel refining installation where the cobalt & nickel containing alloys can be further treated so that pure cobalt and nickel are prepared.
followed by a process for transformation of cobalt products into the final lithium cobalt dioxide LiCoO2 which is then used in the production of new lithium ion batteries.
By developing and patenting a sustainable and cost-efficient VAL’EAS™ battery recycling process, Umicore is the only company in the world proposing a real closed loop solution for Li-ion batteries combined with an environmentally sound management of these end-of-life batteries and high recycling and/or recovery rates.
MIXED PLASTIC WASTE RECYCLING SOLUTINS-1(plastic is visible or hidden in the EEE due to insulation, strength,
resistance, flexibility and durability)Thermoset plastics can’t be remelted and formed
into new products (circuit boards, switch housings, electrical breakers etc)
Termoplastics can be remelted and formed in new products.
Recyclibility of termoplastic resins is better than termoset resins.
TVs: HIPS, ABS, PPE, PVC, PC
Computers: ABS, HIPS, PPO, PPE, PVC, PC
Micellaneous EEE: HIPS, ABS, PVC, PPE, PC
Composition of consumer electronic plastic resin
There are 3 ways of post consumer plastic recycling in the EEE.
1. Chemical Recycling: Use mixed-waste plastics as raw materials for petrochemical processes or as a reductant in a metal smelter. There are 3 processes
a.Depolimerization and Conversion (350-400 C) (Syncrude oil (80%), gas (10%) and solid waste (10%) are produced and sent to petrochemical proceses).
b. Coke Oven Process (carbonization, products are 20% coke, 40% tar, %40 gases (metan and hydrogen)(Japan-Nippon Steel) .
c. Reducing agent for Fe2O3 (instead of coke) in blast furnace (Sweden).
HIPS: high impact polystyrene, ABS: acrylonitrile butadine styrene (impact protection), PPO: polyphenylene oxide (high temperature), PE: Polyethylene , PVC: polyvinyl cholaride (insulator), PC: polycarbonate, PPE: poly-phenylene ether.
MIXED PLASTIC WASTE RECYCLING SOLUTIONS-2
2. Flowsheet of Mechanical Recycling of Mixed Waste Plastics
3. Thermal Recycling of Plastics: Plastic is used as fuel to generate energy.
(1 t EOL plastic = 1.3 t coal in cement kilns)
Switzerland and Denmark thermally recover 70% of their waste plastic in 2002.
In 2003, 23% of total waste plastic of West Europe thermally recycled which is the largest portion in recycling methods.
Solid plastic waste combustion facility must have wet scrubber (APME).
MARKETS FOR RECYCLED PLASTICS
One third of materials in EEE devices is plastic but only 25% of that is clean, homogenous and free from contamination.
Recycled plastics are used for plastic lumber, outdoor furniture, roadbed fill, battery boxes, compact disc trays, camera casings, laminated floorings, automotive parts, pellets, carpet, fabric, fiber, geotextile, desks, trays, bottles etc.
Remove paint, coatings
(Crygenic grinding, abra-sion, solvent stripping etc.)
Shear shredder, hammer mill, Granulators, mills
(liberation)
Foreign materials separation Triboelectric Separation
Swiss Results Technology Inc. (Circuit board plastics separation)
MBA Polimers Inc. (HIPS from TVs)
METALS RECYCLING IN EEE WASTE-1Permanent/Electric Magnetic Separation: Ferrous metals (Fe&steel),
Eddy Current Separation: Non-magnetic metals (Al, Cu) (Conductivity/Density ratio)
SECONDARY LEAD (Pb) RECOVERY- In the reverberatory/rotary furnace,
Pb containg material is reduced to soft Pb bullion (99.9% Pb) by coke and foreign materials are oxidized as slag (60-70% Pb).
Iron and limestone (fluxing)
Final slag
1-3% Pb, CaO, SiO2, FeO
(Disposed of landfills)
(Pb Bullion) low Sb
(%60-70 Pb)
Dust in the flue gas are collected by baghouse
(15-25% Sb)
Britannia Refined Metals (BRM) (UK) Isasmelt Plant Schematic Diagram (30000 tpa)
Desulphurisation by Na2CO3/NaOH to form Pb-oxide and Na2SO4
87%
13%
0.6%
12.4%
Pb Distribution
Kettles
1991
High Sb
Energy Saving: 15-40%
METALS RECYCLING IN EEE WASTE-2
• SECONDARY COPPER (Cu) RECOVERY
• 5-40% Cu containing electronic scrap are fed into a blast furnace. Cu-compounds have to be reduced by scrap Fe and plastics. Sn, Pb and Zn impurities are also reduced as gas fumes.
• Energy needed to reclaim Cu from EOL e-waste is only one sixth of the energy that would be required to produce from Cu ore.
(Coke, wood or plastic)
Air/O2
Scrap Cu
H2SO4
Slag: roof shingles, sand blasting and blasts for railroads
Scrap Fe, plastics
Impurities (Sb, Pb, Zn) burned, Fe goes to slag
Ni, Zn, Fe removed
Burning cables for Cu
Slimes
METALS RECYCLING IN EEE WASTE-3
PRECIOUS METALS RECOVERY
• Au, Ag, Pa and Pt are recovered from anode slime of Cu electrolysis process by pressure leaching.
• The leach residue is then dried and smelted with fluxes in the furnace.
• During smelting Se is recovered; from remaining material, Ag is cast into Ag anode.
• After high-intensity electrolitic refining, a high-purity Ag cathode and Au anode slime are formed.
• Anode Au slime is then leached and high purity Au, as well as Pa and Pt sludge are precipitated.
One third of the precious metals recovered from e-waste are Au, as electronic scrap contains more than 40 times the Au contained in Au ores in the U.S.
PRECIOUS METALS REFINARY PROCESS
Recovering precious metals from e-waste is one of the greatest economic profits for recycling industry in the world.
Se
SOME LEADINGE-WASTE
RECYCLERS
RECYCLER CAPACITY E-WASTE PRODUCT(S) PROCESS
SIMS E-Recycling
(Hydromet/Simsmetal), Unanderra, NSW, Australia (2006)
36000 t/y battery
20000 t/y Pb
2.4 million battery (30%)
Used Pb-acid battery (ULAB)
Pb metal (plates)
Lead oxide (paste)
PP (casings)
Weak acid (H2SO4)
Sold to the secondary lead smelters
Local dealers
Umicore
Antwerp
Belgium
(1887)
World’s largest precious metal recycler
Lion and NiMH batteries
Cellphones
TVs, laptops
Precious metals (Ag, Cu, Pt, Au etc)
(17 metals)
Val’eas process (won EEP gold award in 2004)
(Best Available Technology- BAT)
Metech Inc. (CERL-Singapore)
(Gilroy CA, Wor-chester MA, Durham NC) (USA) (1968)
Engitech SpA.
Italy
1973
Electronic recycling and precious metal refining
3-50 t/h
Computer recycling
Used Pb-acid battery
(55% Pb, 5% PP
Precious/base metals, plastics, glass
Secondary Pb production
Na2SO4/(NH4)2SO4 (fertilizer grade)
ISO 9001-14001
Certified destruction and meterial recovery
Paste desulphirisation
(CX), CX-EWS or Fluoborik (HBF4) hydromet. Technology. Safest, cleanest, cost effective
RECYCLER CAPACITY E-WASTE PRODUCT(S) PROCESS
Exide Technologies
One of the largest secondary Pb recycler in the world)
50 million batteries
10 recycling facilities (6 in USA, 3 in EU and 1 in New Zealand)
Used Pb-acid battery (ULAB)
Pb metal (plates)
Lead oxide (paste)
PP (casings)
Weak acid (H2SO4)
Sold to the battery plants
Cases, covers for new batteries
BSB
Braubach-Germany
(1985)
80000 t/y battery
40000 t/y Pb
Used Pb-acid battery (ULAB)
24000 tpa Pb, 15000 tpa Pb bullion, 1000 tpa Sb alloy, 35000 tpa PP
Paste desulphurisation with Na2CO3
CX
Tonolli
Mississauga- Canada
(1988)
60000 t/y battery
20 million batteries
Used Pb-acid battery
Pb metal and Pb alloys (30000 t/y rafined Pb)
7100 tpa Na2SO4 (detergent/glass grade)
3000 tpa PP
2000 tpa ebonite
Hydrodynamic separator
Paste desulphirisation
(Engitec-CX),
Safest, cleanest, cost effective
C O N C L U S I O N S
• Technological revolution produces faster, smaller and cheaper EEEs. E-waste is inevitable by-product of an exponential evolution of personnel electronic appliances.
• E-waste reduction and producer responsibility from “cradle-to-grave” are becoming important.
• Extended Producers Responsibiity “Take it back, make it clean and recycle”.• Producers should design their products with longer life-span and increased
recyclibility.• E-waste recycling infrastructure for collection and processing are not well
established in the world yet.• Exporting e-waste to overseas and using women/prisoners/childreen are not
right, fair and humanistic solution.• Current recycling techniques are expensive, not automated and depend on
mostly manual operations.• Use Best Available Hydrometallurgical Technologies (BAT) rather than
pyrometallurgical Technologies in e-waste recycling.• 4-6 kg WEEE should be collected per person and 75% of this must be recycled
each year in any country.• Apply “Reduce, Reuse and Recycle (RRR)” waste management hierarchy.• Countries must obey the Basel Convention, WEEE and RoHS directives.• E-waste recycling not only protects environment, but also saves energy and raw
materials.• E-waste recycling market will be a promising sector in the near future.
THANK YOU for LISTENING
Prof.Dr. Muammer KAYA
Eskişehir-Osmangazi University
TECHNOLOGICAL RESEARCH CENTER (TEKAM), TURKEY