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8/13/2019 Matl Recycle
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1Copyright Anders Damgaard & Morton A. Barlaz, NC State University
Material recycling
Outline Objective of material recycling
Purpose of reuse in industry
Recycling Components of the MSW Stream
Aluminum Glass
Steel
Plastics
Paper
Tires
Copyright Anders Damgaard & Morton A. Barlaz, NC State University
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2Copyright Anders Damgaard & Morton A. Barlaz, NC State University
Objective
Examine recycling process for each material, alternativetechnologies, projected markets
Demand and economics have a significant influence on
recycling activity Is it consistently marketable?
What limits recycling?
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3Copyright Anders Damgaard & Morton A. Barlaz, NC State University
Purpose of reuse in industry
Ensure raw materials to national industry: Paper, glass, metal.
Economy: Waste materials are cheaper than virgin materials at thegate of the plant (price of raw materials, transport of raw materials)
Manufacturing is cheaper (energy, emissions, waste & costs) Life-cycle assessment shows overall benefits (less virgin materials
used, less landfilling and maybe less treatment)
In the latter case, global assessment may be different than that of the
industry and regulations / incentives may be needed to improve recycling
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5Copyright Anders Damgaard & Morton A. Barlaz, NC State University
Paper: Remanufacturing 1Chemical-mechanical re-pulping
Chemical-mechanical re-pulping is used for higher-quality products requiringremoval of ink and maybe bleaching. Chemical-mechanical re-pulping including thecleaning process typically consists of seven steps (Virtanen & Nilsson, 1993):
Feeding and pulping including pH adjustment (caustic soda, aluminum sulfates)and addition of dispersing agent (e.g. glycol ether)
Pre-cleaning (mechanical) removes solid foreign items using centrifuges andpressure sorters
Refining provides washing, sorting and milling of the pulp
De-inking and pigment removal by chemical (water glass, etc,) and mechanical(flotation) treatment steps.
Final cleaning (mechanical) Thickening and bleaching (heating with hydrogen peroxide or sodium
hypochlorite) and storing
Drying
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6Copyright Anders Damgaard & Morton A. Barlaz, NC State University
Paper: Remanufacturing 2
Mechanical re-pulping Mechanical re-pulping is used for less demanding paper qualities such as brownpaper, boards, egg containers, etc. Mechanical re-pulping including the cleaningprocess typically consists of six steps (Virtanen & Nilsson, 1993):
Feeding and pulping including pH adjustment (caustic soda, aluminum sulfates)and addition of dispersing agent (e.g. glycol ether).
Pre-cleaning (mechanical) removes solid foreign items using centrifuges andpressure sorters.
Refining provides washing, sorting and milling of the pulp.
Final cleaning (mechanical) to remove items released in the refining step.
Thickening reducing the water content and allowing for storing. Drying
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7Copyright Anders Damgaard & Morton A. Barlaz, NC State University
Paper Recycling 1: Major Grades
There are about 80 grades of fiber
Major grades:
1. Pulp substitutes
Unprinted trimmings from envelopes and high grade paper
Generated in paper mills only
Primarily reused in tissue, also in book stock
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8Copyright Anders Damgaard & Morton A. Barlaz, NC State University
Paper Recycling 2: Major Grades
Post Consumer
2. High grade deinking
Office white paper
3. Old corrugated (OCC)
4. Old newsprint (ONP)
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9Copyright Anders Damgaard & Morton A. Barlaz, NC State University
Paper Recycling 3 Major Grades
5. Residential mixed paper (RMP)
office waste, third class mail, boxboard (cereal boxes), magazines,telephone books, OCC, coated packaging
6. Mixed office paper7. OMG - old magazines
8. OTP - old telephone books
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10Copyright Anders Damgaard & Morton A. Barlaz, NC State University
Paper Recycling 4: ONP
~4% of MSW in 2010 (includes 18.8% advertising)
~70% recovery rate
Uses:
largest use is in new newsprint
recycled paperboard
cereal & shoe boxes, tablet backs
cellulose insulation, roofing felt
animal bedding
export
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11Copyright Anders Damgaard & Morton A. Barlaz, NC State University
Paper Recycling 5: ONP
Specifications
#6 news -
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12Copyright Anders Damgaard & Morton A. Barlaz, NC State University
Cardbox Composition
Linerboard - The inside and outside of a box that confers strength
Medium(fluting) - fluted section in between linerboard
Containerboard a box
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13Copyright Anders Damgaard & Morton A. Barlaz, NC State University
Paper Recycling 6: OCC
~12% of MSW (2001)
~71% recovery rate
Uses:
Container board (linerboard and corrugating medium)
news boxes require 20% OCC
construction products
wallboard, roofing felt
Paperboard
Dec. 2012 Prices 70-130 $/ton
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14Copyright Anders Damgaard & Morton A. Barlaz, NC State University
Paper Recycling 7: OFF
There are a number of grades of office paper:
office paper only
white copy and pad paper
standard office mix that may include: envelopes (with and without plastic)
mail including coated papers
colored paper
folders and card stock
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15Copyright Anders Damgaard & Morton A. Barlaz, NC State University
Paper Recycling 8: Office Paper (OFF)
ISRI Grades & 2006 Price:
127: sorted white ledger
119: sorted color ledger Mixed Office Paper
Clean, sorted ledger & writing papers, free of brown grades,cardboard, boxboard, may contain up to 10% groundwood
paper fiber content
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16Copyright Anders Damgaard & Morton A. Barlaz, NC State University
Paper Recycling 9: Office Paper (OFF)
Problems
no consistent definitions/varying markets
adhesive labels, stamps
paper clips, plastics grey and brown products (brightness)
Uses:
historically tissue paper
printing and white (somewhat grey) paper is a newer use
Federal agencies must use paper with 30% recycled content by1998
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17Copyright Anders Damgaard & Morton A. Barlaz, NC State University
Paper Recycling 10: Old Magazines (OMG)
Coated magazine and catalog papers
OMG facilitates ONP ink flotation
Ample market capacity given high demand for ONP
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18Copyright Anders Damgaard & Morton A. Barlaz, NC State University
Paper Recycling 11: Residential MixedPaper (RMP)
May contain OMG, books, ONP, third class mail, envelopes,foodcartons and OCC
A relatively low quality fiber but incentives to use:
cheap and in large supply Uses are limited due to fiber length:
Egg cartons, roofing felt, fruit, separators
Boxboard and wallboard backing
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19Copyright Anders Damgaard & Morton A. Barlaz, NC State University
Paper Recycling 12: RMP
May be used where shortages of other paper grades develop
Price will depend on availability of better papers
Solid waste manager must figure out what to separate and what to
leave as mixed paper Flexibility is key
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20Copyright Anders Damgaard & Morton A. Barlaz, NC State University
Paper Recycling 13
Effects of recycling
weaker fibers
decreased burst strength
stiffer paperThis decreases ability to light weight a box
Losses During Recycling:
OCC: 10-15%
OMG: 40-60%
OFF: 8-20%
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21Copyright Anders Damgaard & Morton A. Barlaz, NC State University
Paper Recycling 14: European paper flows
Ref: CEPI, 2004
Million tonnes
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22Copyright Anders Damgaard & Morton A. Barlaz, NC State University
Paper Recycling 15: Paper market prices
Ref: Danfiber, 2009
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23Copyright Anders Damgaard & Morton A. Barlaz, NC State University
Container Glass: Short version
Glass is made primarily from sand (quartz), soda and lime; none-renewable but not scarce resources
Problems with post-consumer glass: Mix of colors, foreign objects
(ceramics, metal caps). More than a few percent of wrong coloraffects the color of the remanufactured product
Major benefits: Energy savings in production
Products: Glass containers/bottles, insulation material
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24Copyright Anders Damgaard & Morton A. Barlaz, NC State University
Glass: Types
Soda-lime glass, which is used for bottles, jars, drinking glassesand window glass, is typically produced from 70-75% quartz sand(SiO2, particle size 0.1-0.4 mm), 12-16% soda (Na2O, Na2CO3),10-15% lime (CaO, CaCO3) and traces of other materials.
Crystal glass, which is used for high-quality drinking glasses, vases,art etc, is typically produced from 54-65% SiO2, 18-38% PbO, 13-15% Na2O or K2O and various other oxides.
Borosilicate glass (Pyrex glass), which is used for laboratory glassware, kitchen glass ware and high temperature lamps, is typicallyproduced from 70-78% SiO2, 7-13% B2O3, 4-8% Na2O and K2O,and 2-7% Al2O3. Borosilicate glass is corrosion and temperatureresistant.
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25Copyright Anders Damgaard & Morton A. Barlaz, NC State University
Container Glass Recycling 1
Glass is about 5.5% of MSW / 90% containers
beer and soda
food jars
wine/liquor ~55% clear (flint)
~6% green (50% imported)
~38% brown (amber)
Only container glass can be recycled
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26Copyright Anders Damgaard & Morton A. Barlaz, NC State University
Container Glass Recycling 2
Recycling processing
Color separation is critical due to tight specs on end product(glass containers)
optical sorting possible at regional level Source separation is most efficient as breakage reduces ability to
separate colors
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27Copyright Anders Damgaard & Morton A. Barlaz, NC State University
Container Glass Recycling 3
Pricing ($/ton) Dec. 2009
end userClear 29Brown 17
Green 8 Market for recycled glass
historically stable (except green) market share is shrinking due to plastic
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28Copyright Anders Damgaard & Morton A. Barlaz, NC State University
Container Glass Recycling 4
Uses
new beverage containers
these alternates provide a market for mixed color glass
substitute for stone and sand in asphalt (up to 20%) fiberglass insulation
drainage material
1992: California required fiberglass manufacturers to use 30%
recycled glass
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29Copyright Anders Damgaard & Morton A. Barlaz, NC State University
Container Glass Recycling 5
Processing
Shipped either crushed or loose
Cullet (crushed glass) requires less energy to melt compared to
sand & already contains additivesSpecifications
clear - 95%, green and brown - 90%
no metal, rocks, ceramic
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30Copyright Anders Damgaard & Morton A. Barlaz, NC State University
Aluminum: Short version
Aluminum is obtained under great energy expenses from minedbauxite, a limited non-renewable mineral
Problems with post-consumer aluminum: Few if clean from other
metals Major benefits: Energy savings in production, preserving a resource
with a large environmental signature
Products: Any new aluminum product. No loss of quality
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32Copyright Anders Damgaard & Morton A. Barlaz, NC State University
Aluminum Recycling
What can be recycled?
Essentially everything - the only limit is cleanliness and pricepaid
Price structure (Dec. 2012):delivered to end user
UBC - Used beverage can 1200-1800 $/tonClean scrap higher Foil lower
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33Copyright Anders Damgaard & Morton A. Barlaz, NC State University
Market Conditions
The aluminum companies will buy as much as they can get
Recycled aluminum is used for: New beverage cans - 27%
Building and construction - 21%
Transportation - 21%
Electrical goods - 9%
Other - 23%
Major barrier to aluminum recycling is collection
National UBC recovery rate is
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34Copyright Anders Damgaard & Morton A. Barlaz, NC State University
Aluminum Recycling
Processing of used aluminum
Shred, flatten or bail for transport, cans are actually blown into atrailer
Tremendous energy savings realized with use of recycledaluminum
~95% energy saving in production
Eliminates energy for mining
Requires energy for collection
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35Copyright Anders Damgaard & Morton A. Barlaz, NC State University
Iron / steel: Short version
Iron / steel is obtained under great energy expenses from minedore. Iron is a non-renewable mineral, but rather abundant
Problems with post-consumer : Few if clean from other metals (tin
as plating, lead as solder) Major benefits: Energy savings in production, preserving a resourcewith a large environmental signature
Products: Any new iron product. If tin or lead have penetrated intothe iron, the quality may be lower
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36Copyright Anders Damgaard & Morton A. Barlaz, NC State University
Steel Recycling
7.9% of solid waste stream
22% of steel is food and beverage cans
58% -appliance, furniture, tires, other durables (excludes - cars,
construction waste) Ferrous metal is easily separated from shredded MSW with
magnets but this is quite rare (~95% pure)
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37Copyright Anders Damgaard & Morton A. Barlaz, NC State University
Steel Recycling Depending upon the furnace type - can utilize 20 to 100% scrap as
raw material Market is soft and fluctuates but overall market capacity is adequate
Controlled by price at scrap yard
White goods - dealers may charge if they contain CFCs
Pricing (Dec. 2012)Cans 100-200 $/ton
Ref: Danfiber, H.J. Hansen, Westmetall, 2009
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38Copyright Anders Damgaard & Morton A. Barlaz, NC State University
Plastics Recycling
~12% of MSW stream by weight
Plastics - polymers that can be formed into shapes, typically by theapplication of heat and/or pressure
Two categories thermoplastics: soften when heated and can be remolded
(recycled)
85% of manufactured plastic
thermosetting: do not soften when heated and cannot beremolded, limited opportunity for recycling
15% of manufactured plastic
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39Copyright Anders Damgaard & Morton A. Barlaz, NC State University
Plastics Production
Raw materials:
ethylene oxide, benzene
Raw materials ---> resin (petrochemical industry) ~300
Resin ----> molded products (independent producers) 1000's hundreds of types of resins
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40Copyright Anders Damgaard & Morton A. Barlaz, NC State University
Plastic Recycling
Plastics can only be recycled if separated by resin type
Currently no mechanical processes are available to sort plastic frommixed refuse
Sortation of HDPE/PET/PVC can be done
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41Copyright Anders Damgaard & Morton A. Barlaz, NC State University
Types Of Thermoplastics: HDPE
High density polyethylene (HDPE)
Consumer products:
Containers for milk, water, foods, oil (~0.3% of MSW)
Major division for recycling: translucent HDPE - milk and water jugs (0.05 0.30 $/lb baled)
pigmented HDPE - household industrial chemical containers(HICs) (0.13 0.22 $/lb):
oil, detergent, shampoo
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42Copyright Anders Damgaard & Morton A. Barlaz, NC State University
Types Of Thermoplastics: HDPE
Recycle market:
Need for translucent/pigment separation is not alwaysnecessary
some MRFS ship mixed PET/HDPE (lower value) Products:
Garbage bags, flower pots, speed bumps, drain pipes, autoparts, films, toys,
Sandwich layer in bottles
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43Copyright Anders Damgaard & Morton A. Barlaz, NC State University
Types Of Thermoplastics: PET
Polyethylene terephthalate (PET)
Consumer products: soda and liquor bottles
beverage bottles - ~0.4% of MSW
custom PET is other recyclable component Major recycled markets:
carpets, polyester fiberfill, auto parts, textiles (~70%)
approved for contact with food (1998)
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44Copyright Anders Damgaard & Morton A. Barlaz, NC State University
44
Types Of Thermoplastics: PET
The most widely recycled resin because 30% of the U.S.population lives in bottle bill states
Also the most valuable plastic resin
ethylene glycol plus dimethyl terephthalate
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45Copyright Anders Damgaard & Morton A. Barlaz, NC State University
Types Of Thermoplastics: Polystyrene
(PS) (Styrofoam)
Consumer products:
Fast food packaging, packing for shock insulation, eatingutensils, dairy containers
Recycled markets: Packing for shock insulation, desk accessories
Recycling:
Technically feasible
Limitations: cost due to light weight
cost to wash
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46Copyright Anders Damgaard & Morton A. Barlaz, NC State University
Types Of Thermoplastics: PVC
Polyvinyl chloride (PVC)
has been a shift away from use in household containers
it burns before PET melts
Polypropylene (PP) Films, Textiles
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48Copyright Anders Damgaard & Morton A. Barlaz, NC State University
Products for which the majority is made
from one resin
Item Resin/ Share of Product
Food Packaging Film LDPE/ 65%
Carryout bags HDPE/ 63%
Dairy containers HDPE/52%Pipe and conduit PVC/ 96%
Trash bags LLDPE/ 62%
HIC bottles HDPE/ 80%
LLDPE - Linear Low Density Polyethylene
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49Copyright Anders Damgaard & Morton A. Barlaz, NC State University
Plastic Recycling
What left must be treated as commingled plastic
it can be made into plastic lumber
development of construction specifications
expensive relative to wood for all but high end uses, needspecific uses
new life as CCA treated lumber is banned
Other sources of pure material:
pallet wrap process trimmings
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50Copyright Anders Damgaard & Morton A. Barlaz, NC State University
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Barriers To Recycling
1 Collection/participation
2 Cost of resin fluctuates
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51Copyright Anders Damgaard & Morton A. Barlaz, NC State University
Wood Waste
Pallets, tree trimmings, land clearing debris
Typically comes in Monoloads"
Markets BioCycle,Jan., 1995: $/ton
Paper pulp 2-5
Wood composite materials 5-35
Fuel (8500 BTU/lb) 0-20
Mulch 0-10
Landfill cover 0-2
Road stabilization ?
animal bedding 0-20
The distance to market is critical as the value is low: transportationcost - 0.1 $/ton-mi
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52Copyright Anders Damgaard & Morton A. Barlaz, NC State University
Tire Recycling
Generation rate ~ 1 per person per year
290 million generated in 2003
Proper inflation = source reduction!!
Unique problems Whole tires do not stay buried in landfills
Serve as breeding grounds for mosquitoes
Present a special fire hazard
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53Copyright Anders Damgaard & Morton A. Barlaz, NC State University
Tire Recycling
Alternative uses for tires
Retreading
Direct reuse
combustion tire derived fuel (TDF) Reuse in other products
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54Copyright Anders Damgaard & Morton A. Barlaz, NC State University
Tire Recycling
A tire contains three components:
Rubber (~12 lb)
Fabric (~4 lb)
Metal (~4 lb) In several layers:
Rubber
Beads
Fabric and steel Rubber / tread
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55Copyright Anders Damgaard & Morton A. Barlaz, NC State University
Tire Recycling
Combustion
As "tire derived fuel" in industrial boilers (~50% of all tires)
Cement kilns where the lime in cement neutralizes the SO2
Whole or 2" chips Paper industry boilers
2" chips
Utilities -- ?
http://www.rma.org/scrap_tires/
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56Copyright Anders Damgaard & Morton A. Barlaz, NC State University
Tire Recycling
Reuse in other products
Drainage material CE Applications (14.2% in 2001)
leachate distribution
septic fields erosion control
subgrade fill
backfill for walls and bridge abutments
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57Copyright Anders Damgaard & Morton A. Barlaz, NC State University
Tire Recycling
Crumb rubber for low end rubber products (11.7% in 2001)
car mats
mud flaps
shoe soles carpet backing
tires for wheel barrel and tricycles
recreational surfaces (e.g. tennis courts)
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58Copyright Anders Damgaard & Morton A. Barlaz, NC State University
Copyright Morton A. Barlaz, NC State University 58
Low end rubber products (contd.)
Overall demand is not adequate
Over 50% of U.S. demand for rubber is for tires Any time crumb rubber is produced, steel and fiber remain
for disposal
Use in asphalt rubber mixtures
Technically feasible but typically not as viable as combustion
Tire Recycling
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59Copyright Anders Damgaard & Morton A. Barlaz, NC State University
Tire Recycling
SUMMARY1. Use in cement kilns, and use in other boilers as TDF works well
and is dominant outlet2. Demand for use as a drainage material varies with location
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60Copyright Anders Damgaard & Morton A. Barlaz, NC State University
Material Markets
Prices are volatileBLS OCC National
0
50
100
150
200
250
300
12/1/1986 3/1/1988 6/1/1989 9/1/1990 12/1/1991 3/1/1993 6/1/1994 9/1/1995 12/1/1996 3/1/199
Deflated by the ppiBase 12/86
MonthlyPriceIn
dex
Overview of Futures Markets
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61Copyright Anders Damgaard & Morton A. Barlaz, NC State University
Material Specifications
Often subjective but reputation is critical
MRFs and processors must have end users (purchasers)
Often will take less money for sales guarantees
Specifications vary with the plant capability
with material demand over time