crt recycling cullet activities lgphilips displays

CRT cullet recycling


- Joint Venture between LGE and Philips

(2001)

- World’s Leading CRT producer

- Number one CPT (TV CRTs) company

- Revenue 2004 at 4bln USD (67M CRTs)

- LPD serves ~ 30% of the CRT TV market

- First company to introduce SuperSlim

(2004)

LG.Philips Displays


LG.Philips Displays glass operation

Glass Development Eindhoven

Glass Factory Aachen

Glass Factory Zhengzhou

Glass Factory Capuava

Glass Factory Suzano


LG.Philips Displays Superslim CRT


CRT glass products


Electron beams

Deflection yoke

Gun

Screen

Glass cone

Picture : Scheme of an operating CRT


Why recycling of CRT glass?

•Mature market: heavy price erosion

•Raw materials prices increase (energy price, transport, shortages)

•WEEE legislation, recycling is strongly supported by governments

•Energy savings

•CO2 emission (future issue)


What is CRT cullet ?

• Cullet are pieces of broken CRT glass

• In general, the CRT glass factories can use cullet of similar

compositions

• funnel glass is used for funnel glass production

• panel glass is used for panel glass production

• mixed glass (panel + funnel) is used for funnel glass production


Function of cullet• Primary functionsPrimary functions •Essential part of the glass recipe to produce new CRT glass

• Cullet is raw material and is used in the mix with other raw materials

to produce the final glass composition

Without cullet glass melting operation is economically and technically not feasible

Secondary functionsSecondary functions•Mixing tower

• Helps to mix the raw materials, helps the flowability in the silo,

cleans the chargers

•Melting process

Accelerates melting process by lowering the melting temperature,

increases the furnace lifetime, saves energy, reduces emission of dust


Origin of the cullet

• Reject from own production process (Glass factories)

• Reject from the tube production process (tube factories, set makers)

• Cullet recycled from the old TV sets and monitors so called EOL (End Of Life) cullet


What are the benefits of CRT cullet recycling?

• Melting on lower energy, less fuel (oil, natural gas, electricity) needed

•Example: Yearly saving of 1 Mio m3 gas at production and 1,4 Mio m3 gas at the suppliers

• Less CO2 emissions since the carbonates are already transformed to oxides

•Example: Net output glass 45000 t/y, 30 % cullet means about 4000 tons less CO2 emission

• Less particles emissions since cullet does not produce dust

•The cullet is not disposed to the landfill but brought back into closed loop “glass to glass recycling”

•Less mining of raw materials required if recycling cullet is used


LG.Philips CRT cullet recycling program

• Recycling program started in the early 1990’s

• The scope of this program was to develop a solution for the increasing problem of land filling of the CRT glass

•Other solutions than “glass to glass recycling” are environmentally not accepted

• A research was made focusing on upgrading the CRT glass to be able to use it in the CRT glass melting process

• A new raw material was developed: ECORAM

• This material was successfully introduced at LGPhilips glass factories worldwide

•Panel glass in panel glass and dedicated cone glass recycling is also standard practice


Issues for CRT glass recycling•Separation of panel and funnel (different glass types)

•Cleaning

•Metal separation

•Separation of organic materials

•Separating ceramic materials

•Dealing with variations in glass composition and glass properties

•Selecting the right grainsize

•All on a level of less than 10 glassfaults/ton, with long required furnace lifetime and a sensitive mass production process

•See “Recycling of TV glass, Profit or doom?”

(American Ceramic Society Bulletin vol. 80, no 3 p. 51-56)


CRT recycling cullet quality

• Because CRT cullet is raw material there are very high quality demands

• critical impurities to product reject

Ceramics stones

Organic material bubbles

Cullet homogeneity cords

• Critical impurities to furnace damage

Organic material lead reduction

Alumina coatings lead reduction

Metal contamination Metal (lead) reduction


Special issues for crystal glass

Similarities:

•Glass types ( lead crystal and barium crystal glass)

•High quality demands

•Heavy pressure on costprice

Differences

•Volume issue: smaller volume means less economy of scale

•Recycling firms are not yet ready to meet demands

•Extremely strict demands on transmission

•Lead oxide will be phased out (RoHS)


ConclusionCRT cullet is essential part of the glass recipe and without cullet CRT glass making is economically and technically not feasible

The CRT recycling glass is used as raw material instead of the raw materials produced by mining and chemicals

If recycling cullet is used less raw materials are mined or chemically produced which reduces the environmental impact and CO2 emission

By using CRT recycling glass the CO2 emission into atmosphere is being reduced by about 14 %. So for each ton of CRT recycling glass used about 140 kg CO2 is saved

The only practical solution to avoid land filling is to support the “glass to glass recycling’.

Crystal glass can profit a lot from experience of CRT and container glass recycling, but specific issues need to be addressed

crt recycling cullet activities lgphilips displays

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