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Step Webinar “The CRT Challenge”
Rolf Widmer, Empa
What? CRTs are still alive?
ca. 1900
ca. 2000
Widmer "The CRT Challenge", Step Webinar June 2016 2
CRT issues
CRTs are replaced by new screen technologies: the world is confronted with large stranded CRT stocks.
Developing countries are at risk to become the final sink of CRTs because they are the last users and producers of CRTs.
They urgently need feasible options for alternative recycling and disposal routes.
Pb-free CRT glass has found a stable market in the container glass industry (Europe).
Pb-containing CRT glass is the issue - should be recycled or disposed to carefully selected applications.
Cathode Ray Tube (CRT) screens contain 1 to 1.5 kg of Pb per screen. Pb is both toxic and (geochemically) rare. If available recycling options are not acceptable, an interim storage
should be considered where Pb-containing CRT glass remains under control and accessible.
Widmer "The CRT Challenge", Step Webinar June 2016 3
CRT components
Widmer "The CRT Challenge", Step Webinar June 2016 5
cathode
cone glass
shields
frit glass (solder)
front glass fluorescent screen
deflecting unit
electron beams
neck glass
shadow mask
35% of glass is funnel, neck and frit 10 to 25% of funnel is PbO
up to 85% of display is glass
up to 65% of glass is Pb-free panel
Comparison of CRT glass demand vs. supply
Widmer "The CRT Challenge", Step Webinar June 2016 6
Global supply and demand (for production of new CRTs) of CRT glass cullet Source: Gregory et al., 2009
Evolution of CRT globally [t]
Widmer "The CRT Challenge", Step Webinar June 2016 7
-
500 000
1000 000
1500 000
2000 000
2500 000
3000 000
3500 000
4000 000
2009 2014 2017
Evolution CRT glass in globally WEEE generated
Non-Pb GlassPb Glass
-
200 000
400 000
600 000
800 000
1000 000
1200 000
1400 000
2009 2014 2017
Pb-glass regional generation
Oceania
Europe
Asia
Americas
Africa
Evolution of CRT in Europe
Widmer "The CRT Challenge", Step Webinar June 2016 8
0
200000
400000
600000
800000
1000000
1200000
2011 2013 2015 2017 2019 2021 2023
Tota
l Mas
s /
t
Evolution CRT glass in WEEE generated
Non-Pb Glass
Pb Glass
-
200 000
400 000
600 000
800 000
1000 000
1200 000
1400 000
2011 2013 2015 2017 2019 2021 2023
Tota
l Mas
s /
t
Evolution of CRT-TV & PC Waste Generated in EU28 ++ (35 countries)
Simulation and measured CH-Data (2015) average lifetime: CRT-TV 10 Jahre, CRT-PC 7 Jahre (Gaussverteilung)
Widmer "The CRT Challenge", Step Webinar June 2016 9
CH CRT-Glas forecast 2016 - 25
Widmer "The CRT Challenge", Step Webinar June 2016 10
CRT treatment in CH
Widmer "The CRT Challenge", Step Webinar June 2016 11
CRT treatment in CH and EU
Widmer "The CRT Challenge", Step Webinar June 2016 12
Eliette Restrepo, Rolf Widmer, Mathias Schluep
StEP review till end of 2015: Federico Magallini, Jaco Huisman, Colton Bangs, Patricia Whiting, ... Outsider: Jhoanna Rosales, Andriana Kotovrakis, ...
Recycling and Disposal Options for Leaded Glass from CRTs
Questions we wanted to answer
1. What are alternative recycling and disposal options for CRT leaded glass, especially for developing countries? (Literature review *)
2. Which recycling or disposal option is better technically, environmentally and economically? (Multiple Criteria Decision Analysis (MCDA) **)
3. What are the consequences of implementing a recycling option in the demand and supply of raw materials replaced? (Comparison of demand and supply of CRT leaded glass for each option worldwide)
Widmer "The CRT Challenge", Step Webinar June 2016 14
* approx. 100 references ** V. Belton, and T. J. Stewart, Multiple Criteria Decision Analysis: An Integrated Approach, 2nd ed. Norwell, Massachusetts USA: Kluwer Academic Publishers, 2003.
Smelting flux (e.g. for Cu smelting) Crystal glass
Alternative recycling: 8 options
Clay bodies Foam glass Concrete
Recycling CRT to CRT (close-loop)
Hazardous waste landfill
Disposal/Storage: 3 options
Backfilling old mines
Lead metal (e.g. for batteries)
Ceramic glazes
Waste vitrification glass
Interim storage of glass cullet
No longer possible
Feasibility scale
High Medium Low
Results (1/2)
Widmer "The CRT Challenge", Step Webinar June 2016 16
Application Pb glass demand/Mt Lead metal for batteries 139.66 Waste-vitrification glass n.i. Smelting flux 0.12 Clay bricks 26.25 Ceramic glaze 0.09 Concrete 3'470.92 Crystal glass 0.02 Foam glass n.i.
Results (2/2)
Widmer "The CRT Challenge", Step Webinar June 2016 17
Application # CRT supply / demand Concrete 200 000 000 000 0.0003 Lead metal for batteries 8 200 000 000 0.007 Clay bricks 5 100 000 000 0.01 Smelting flux 6 900 000 8.5 Ceramic glaze 5 300 000 11.2 Crystal glass 1 100 000 53.0
Themes Technology Health and
Environment Economy
Criteria Material
replacement Global
demand Indispensability
of Pb Pb
leaching
Retrievability
from application
Price of material replaced
Importance Medium Medium High High Medium Medium
Scoring method A A C B A B
Scoring methods
A
B
C
Ranking and assigning score equal to ranking position [1,2,3…n] ; n = number of options evaluated
Binary score [0,1] ; 0 = properties of lead are not required / does not comply with permitted levels 1 = properties of lead indispensable / complies with permitted levels
Ternary score [1,2,3] ; 1 = irretrievable 2 = moderate retrievability 3 = retrievable
Assessment method
Widmer "The CRT Challenge", Step Webinar June 2016 18
Multi-Criteria Decision Analysis (MCDA *)
Score Table (sorted according total score)
Options Evaluation criteria overall score
(geom. average)
Product main application
Technology Health & Enironment Economy Material
replacement Global
demand Indispensa-bility of Pb
Pb leaching Retrievability
from application
Price of material replaced
Options for Open-loop Recycling metal. lead car batteries 11 6 1 1 3 9 1.97 Flux Cu- & Pb-
smelter 3 4 1 1 2 6 1.57
Vitrification Nuclear wastes 11 1 1 1 1 7 1.48 Glaze floor tiles 4 3 0 1 1 6 - Bricks above ground 5 5 0 0 1 5 - Concrete above & under 2 7 0 0 1 4 - Cristall glass stem ware 11 2 1 0 1 8 - Foam glass therm. insul. 1 1 0 0 1 6 -
Options for Disposal Interim storage 11 1 1 1 3 1 1.37 Landfill 11 1 1 1 2 1 1.32 Backfill 11 1 1 1 1 1 1.24
Widmer "The CRT Challenge", Step Webinar June 2016 19
overall score: geometric mean (based on Cobb–Douglas and mariginal utilities)
𝑆 = 𝑠𝑖
𝑛
𝑖
𝑛
Swicos' Bildröhrenmanagement bis 2020
Stand Ende 2015
R. Widmer
An interim storage for Swiss CRT-cullets
max. storage amount decreases sharply with a later AD failure
the destocking depends on the runoff (here 600 t/a as flux in Cu Pb smelter)
costs depend on the requirements for pre-processing of CRT (cleaning & sorting of cullets prior to storing)
cumulative Siwss CRT glass stocks, if AD fails and MC stays (lines for year of AD failure)
Widmer "The CRT Challenge", Step Webinar June 2016 21
Conclusion
Pb is both toxic and rare: recycling options to "dilute" the lead contained in CRT glass should not be a solution!
Currenly best open-loop recycling options: 1. Use leaded glass to extract the lead for lead-acid battery production
(however, Pb batteries may decline together with ICE-car production) 2. Use leaded glass as smelting flux in Cu and Pb smelters (however, current
demand is 8x lower than potential supply) 3. Use leaded glass to vitrify waste (e.g. nuclear waste, however, this is not
widely tested yet) Interim storage is the most attractive disposal option. Future
applications of Pb are in sight (e.g. solar pv cells) None of the options are profitable, a financing strategy/scheme for
attractive options (e.g. smelter, storage) needs to be defined/implemented
Widmer "The CRT Challenge", Step Webinar June 2016 22
Webinar discussion points
The assessment results depend on the scoring scheme. Ours has 2 'killer indicators' (yes/no) (based on legal requirements) Pb techn. required and possible Pb leaching. Is this biased? how to improve?
If an interim storage option is pursued what are the implications (technical, financial, legal, ...) in particular for developing countries?
...
Widmer "The CRT Challenge", Step Webinar June 2016 23
Thank you!
Widmer "The CRT Challenge", Step Webinar June 2016 24
Indicators, e.g. demand for CRT glass For glass replacements
𝐷𝑖 = 𝑤𝑥𝑖 × 𝑤𝐶𝐶𝐶𝑥 × 𝐺𝑖 Where: Di = Demand of CRT glass for recycling option i worldwide; in mass units wxi = Mass fraction of material x (to be replaced by CRT glass) in product i wCRTx= Mass fraction replacement of material x by CRT glass in product i Gi = Global production of product i
For lead metal replacements
𝐷𝑖 = 𝐷𝑓𝑓𝑤𝑓
; 𝐷𝑓𝑖 = 𝐺𝑃𝑃𝑓𝜀𝑃𝑃
× 𝑀𝑟𝑃𝑃𝑟𝑀𝑟𝑃𝑃
Where: Dfi = Demand of CRT leaded glass for production of product i wf = Mass fraction of CRT leaded glass in CRT glass GPbi = Global demand of Pb for production of product i εPb = Efficiency in Pb recovery from CRT leaded glass MrPbO = Molecular weight of PbO MrPb = Molecular weight of Pb
Widmer "The CRT Challenge", Step Webinar June 2016 25
Indicators of open-loop recycling and disposal options
Widmer "The CRT Challenge", Step Webinar June 2016 26
Optionen Bewertungskriterien potenzieller CRT
Jahres-bedarf
Quellen Produkte Hauptanwendung Technologie Gesundheit + Umwelt Wirtschaft
möglicher Rohstoffersatz durch Bleiglas
weltweite Bleiglasnachfrage
Unerlässlichkeit von Blei
Blei-Auslaugung in Wasser, Boden
und Lebensmittel
Rückgewinnbarkeit von
Blei
Marktreis der er-setzten Rohstoffe
kg/kg Mt ja/nein mg/l hoch/mittel/ tief
USD/t Millionen
Optionen für Open-loop Recycling metallisches Blei Starterbatterien 1 48.88 ja n.i hoch 1'994 8'000 [50], [51],
[53]–[56], [58], [59]
Flussmittel Cu- & Pb-Hütten 0.1* 1.18*** ja 0.01 tief 44.78 6 [58], [66] Beton Hoch- & Tiefbau 10% volume of
fine aggregates 1 214 nein 1.42 tief 7.65 204'000 [58], [74],
[101] Tonziegel Hochbau 0.03 26.24 nein 1 tief 10 5'000 [64], [65] Schaumglas Wärmeisolation 1** n.i. nein 0.1 tief 44.78 n.i. [51], [58],
[79], [102] Keramikglasur Bodenfliessen 0.5* 0.03 nein n.i. tief 44.78 5 [41], [58],
[72] Kristallglas Trinkgläser 1 0.01 ja 0.6 tief 97.8 1 [58], [80],
[81], [85] Vitrifikation Nuklearabfälle 1 n.i. ja n.i. tief 87 n.i. [58], [90]
Optionen für die Beseitigung Reststoffdeponie 1 n.a n.a n.i. tief n.a n.a [15], [93],
[94] Bergbauversatz 1 n.a n.a n.i. tief n.a n.a [95], [96] Zwischenlager 1 n.a n.a n.i. tief n.a n.a -
World's prim. and sec. Pb production
International Lead Association, http://www.ila-lead.org, 07.12.2014 International Lead & Zinc Study Group, http://www.ilzsg.org/static/, 07.12.2014
Widmer "The CRT Challenge", Step Webinar June 2016 27
Pb batteries absorb 85% of the lead demand
International Lead Association, http://www.ila-lead.org, 07.12.2014
Widmer "The CRT Challenge", Step Webinar June 2016 28
addendum
Perovskite solar cells
perovskite
some links: solar technology Empa news (tandem cells)
Widmer "The CRT Challenge", Step Webinar June 2016 29
A perovskite is any material with the same type of crystal structure as calcium titanium oxide (CaTiO3), known as the perovskite structure ... Perovskites take their name from the mineral, which was first discovered in the Ural mountains of Russia by Gustav Rose in 1839 and is named after Russian mineralogist L. A. Perovski (1792–1856). (wikipedia)
Legal requirement CENELEC Norm 50625
The handling of intact CRT devices must not damage to the tube. The necessary measures have to be documented i.e. collection, logistics / transport operators as well as dismantlers must document and possibly prove their effectiveness
Contaminated CRT cullets (phosphor and Pb-glass dust), but probably also vented CRTs must be considered hazardous waste and handled accordingly i.e. it requires "*" waste codes and probably bilateral notifications
The release of pollutants (phosphors and Pb-glass dust) to air and water must be prevented. i.e. explicit evidence is required; it is questionable if current bulk transport is conform
Smashing the CRT and the removal of the phosphor at two distant places is not explicitly prohibited, thus probably tolerable; however, phosphor and Pb-glass dust must be removed prior to any use of the cullets. Thus a future interim storage would require the cullets to be cleaned.
Widmer "The CRT Challenge", Step Webinar June 2016 30
Legal requirement CENELEC Norm 50625
Phosphors should be recycled. Since phosphors and other coatings are already removed from CRTs in wet or dry processes and thus can easily be obtained in a concentrated form, a mandatory recovery of rare earth metals such as europium and yttrium is possible given commodity prices are attractive.
Storage and transport containers for CRTs, which are likely to be contaminated with phosphor and Pb-glass dust, must be cleaned accordingly.
The effective removal of the CRT from the EoL devices and the separation of the leaded glass and the phosphor from the resulting fractions has to be verified in accordance with the future Technical Specification TS 50625-3-3, "Collection, logistics and treatment requirements for WEEE - Part 3-3: Specification for de-pollution - WEEE Containing CRTs and flat panel displays".
Widmer "The CRT Challenge", Step Webinar June 2016 31
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