cradle to ?. material vs. waste when something is useful, we call it a “material” when the same...

Post on 26-Dec-2015

219 Views

Category:

Documents

1 Downloads

Preview:

Click to see full reader

TRANSCRIPT

Cradle to ?

Material vs. waste

When something is useful, we call it a “material”

When the same stuff stops being useful, we call it “waste”

Is waste inevitable?

Yes. Entropy can only increase.

But... we can delay waste

Product Life

Physical Life

Functional Life

Technical Life

Economical Life

Legal Life

Loss of Desirability

Physical life

At some time the product breaks down beyond economical repair

Very common issue. Consider automobiles...

Functional life

at some point the need for the product ceases to exist

buggy whips, for example.

Technical Life

the time at which advances in technology have made the product unacceptably obsolete

Consider 5.25” floppy disk drives

Economical Life

The time at which advances in design and technology offer the same functionality at significantly lower operating cost

Consider old, inefficient refrigerators

Legal Life

The time at which new standards, directives, legislation, or restrictions make the use of the product illegal

Consider R-11 Refrigerant, or DDT...

Loss of Desirability

the time at which changes in taste, fashion, or aesthetic preference render the product unattractive

clothing, for example

What happens to waste?

1. Landfill

2. Combustion

3. Recycling

4. Re-engineering

5. Re-use

Landfill

The land available to fill is finite and reducing.

If consumption of materials grows by 3%/year, and if we discard as much stuff (percentage based) as we do now,

then in the next 25 years we will discard as much material as the entire history of industrialization

Combustion for heat recovery

Can we get some energy back? If we burn the waste, we will generate heat and this can be used as energy.

Requires sorting (combustible vs non-combustible)

Done under control (no toxic fumes)

Imperfect recovery (moisture), 50% efficiency at best, and then conversion to electricity reduces it to 35%.

Neighbors don’t like it.

But still used sometimes (e.g. Concrete industry)

Recycling

Use the waste as a resource.

Recycling is the re-processing of recovered materials at the end of product life and returning them to the use stream.

This is probably the best for extracting value from waste stream

Also needs sorting processes.

Reengineering (Reconditioning)

Refurbishment or upgrading of the product or components.

Consider the axe with 2 heads, 3 handles

Sometimes this is cost-effective compared to replacement.

Airplanes don’t wear out - the are reconditioned

Fashion, perceptions can impede the ability to reengineer a product

Reuse

Reuse is the redistribution of the product to a consumer sector that can use it in its used state.

Sometimes for original purpose (old car), sometimes for another (turn railroad car into diner)

Need to have a good communication/distribution channel. e.g. Ebay.

NaturalResources

MaterialProduction

ProductManufacture

ProductUse

End ofFirst LifeCombustion Landfill

Re-e

ngin

eer

Recycle R

e-us

e

Product at endof first life

Collection Primary Sortingcombustible or not

Secondary Sortingmaterial family, class, grade

1. Landfill

2. Combustion

3. Recycle

4. Refurbish

5. Re-use

Packaging

Packaging ends its functional life as soon as the package is opened.

Ephemeral, trite, wasteful, unnecessary...

But some packaging...

Clothing is a form of packaging.

protection (temperature, abrasions, radiation, precipitation)

signification (gender, cultural, membership, status)

They generate waste, but they are important

Yeah, so...

OK, but objects are inanimate. It must be different?

protection

information

status

presentation....

how bad is it?

Packaging makes up about 18% of household waste and 3% of landfill

Packaging global carbon footprint, about 0.2% of total

In Europe, about 60% of packaging is recovered (less in US)

Necessary for protection of food

extends product life and has reduced food chain waste to about 3%

Provides nutritional information and safety (sell by...)

The industry is aware

Industry knows the problem and perception of packaging and is working on it

Quantity of packing is constantly being reduced

There are long standing recycling routes for many packaging materials, particularly glass, paper, metal, and PET

Recycling Polymers

Recyling markets

Material family

Developed markets for recyled products

Existing secondary uses, but not developed

Metals

Steel/cast ironAluminun, Copper

Lead, TitaniumAll precious metals

Paper/metal foil packaging

Polymers PET, HDPE, PP, PVC All other polymers, including tires

Ceramics and glasses

bottle glassbrick

concrete and asphaltNonbotle glass

Others cardboard, paper, newsprintwood

textiles

Scrap

New, or Primary Scrap (pre-consumer, post-industrial)

cut-offs from billets, risers from castings, turnings from machines

recycled immediately, usually in house

Old or Secondary Scrap (post-consumer)

comes from products at the end of their useful life

Value of Scrap

New scrap has highest value - easy to collect and reprocess

Scrap from commercial sources (offices, restaurants) is more valuable than household scrap because it needs less sorting and is more uniform

Scrap from household sources is the least valuable

Price of Scrap

producers of secondary materials compete with virgin materials

Virgin materials are more expensive

quality is higher (both actual and perceived)

Recycled materials must assure that the drop is quality is acceptable

Legislation can affect this

Time Lapse

It takes time between production of the original product until that product is recycled

If some fraction of currently produced material makes it to scrap, and material consumption increases with time, then the amount of available scrap is reduced in contribution

Recycling effectiveness

Homework

Car tires are a major waste problem.

Indentify the materials that are contained within a typical car tire.

Identify some ways in which the materials contained in car tires can be used.

top related