Transcript Document

Materials and the
Environment
Part 4 – Monitoring, Measuring,
and Assessing Environmental
Impacts
(Most recent update April 1, 2013)
Raw materials extraction activity within
the United States and Canada is subject
to many federal, state, and provincial
laws and regulations.
This is not always the case in countries
from which we obtain raw materials.
Consequently, importing raw materials
that could otherwise have been obtained
domestically not only shifts the
environmental impacts of extraction to
the producing country, but may magnify
them as well.
In addition to laws, there are now
certification programs, operated outside
of government, in which third parties
oversee and evaluate extraction and land
management activity against
independently developed standards.
In the agricultural sector, there is a USDA
certified organic program. In this case,
the program is administered by USDA,
with oversight provided by third-party
agents around the world
With regard to industrial materials,
certification is available only for forest
management and harvesting, with the
majority of certified forests located
within North America.
Forest Certification
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Is there a management plan?
Is it being followed?
Does it provide for:
- Sustainable harvesting?
- Prompt site restoration?
- Protection of soil productivity,
water quality, flora and fauna,
wildlife, high conservation
value forests, historic sites?
- Compliance with all laws?
- Community input?
- Third-party oversight?
Certified Forest Area in North
America in Relation to World Total
(million hectares)
Source: Fernholz and Kraxner (2012).
As yet, there is no
independent oversight or
certification of mining
activity or products.
Beyond landscape impacts, there are a
number of environmental impacts
linked to primary and secondary
processing, transportation, and use.
Production of every material and
every product has environmental
impacts, including recycling.
The impacts, however, differ
considerably.
Identifying environmentally superior
products and practices requires careful
and systematic analysis.
Brainstorming and intuition, commonly
relied upon in making environmental
decisions, are notoriously unreliable.
A growing field of increasing
importance is
Life Cycle Analysis (LCA).
LCA involves measurement and evaluation
of a wide range of environmental impact
parameters, and use of this information to
inform process and product
improvements.
1
Define
Scope
Life Cycle Analysis
2
3
4
Measure
(Inventory)
Evaluate
(Impact
Assessment)
Consider
Improvements
(Improvement
Assessment)
To reduce the environmental impact of
a product, such as this vehicle, requires
careful assessment of each of the parts.
Every component is examined from raw
material extraction or recycling process
to incorporation in the final product.
The same process is followed in
determining the environmental impact
of a building.
The impacts associated with producing
every component are determined.
In determining environmental impacts, the
following are considered:
● Raw material extraction
● Transportation
● All steps in manufacturing
If the “product” is a component assembled on-site
or an entire structure, then also assessed are:
●
●
●
●
●
Transport of materials to const. site
Building construction
Operation (heating/cooling)
Maintenance
End-of-building-life
Through a careful inventory all
inputs and outputs are determined.
Life Cycle Inventory
- Define the product
(individual components,
wall sections, entire
structure)
- Determine materials used.
- Track life cycle
environmental
impacts of every
component.
● Raw material inputs
● Energy consumption
● Emissions
● Effluents
● Solid wastes
● By-products
Do this at every step along the
way, from raw material extraction
to finished product and beyond.
Inventory of Environmental Impacts
● Raw material inputs
● Raw material extraction
● Energy consumption
● Transportation
● Emissions
● Processing to final
product
● Effluents
● Transport to building site ● Solid wastes
● Building construction
● By-products
● Operation (heating/
cooling)
● Maintenance
● End-of-life (disposal/
recycling/energy recovery)
Here is what the life cycle
inventory process looks like
conceptually (this example shows
the inventory process for
production of steel framing
members used in building
construction).
The Inventory Process
Mining
(Transportation)
RECOVERED
STEEL
Crushing/Separation
OTHER
MATERIALS
Refining
ENERGY
(Transportation)
(Transportation)
Smelting
(Transportation)
Forming
(Transportation)
WATER
Steel Products Mfg
(Transportation)
Building Construction
Use/Maintenance
Recycling/Waste Mgmt
EMISSIONS
EFFLUENTS
SOLID WASTES
OTHER RELEASES
PRODUCTS
COPRODUCTS
The result is a great deal of data.
Data gathered in the inventory phase.
Acetaldehyde
Acetone
Acrolein
Organic substances
Arsenic
Cyanide
Benzene
Carbon dioxide (fossil)
Carbon dioxide (non-fossil)
Phenols
Sulfides
Ammonia
Carbon monoxide
Methane
SO2, SO3
Oil and grease
Particulates
Suspended solids
NOx
VOCs
Non-ferrous metals
Dust (PM10)
And hundreds to thousands of other compounds.
The raw data are then evaluated to
determine what the effects of
various emissions and waste
production might be.
Impact Assessment
Embodied energy (GJ)
GWP (CO2 kg)
Air emission index
Acidification potential
Human toxicity
Photochemical oxidation
Ozone layer depletion
Depletion of non-renewable
resources
Water consumption
Eutrophication
Solid waste (total kg)
This information forms a basis for
rational thinking about how the
environmental impacts of a product
or process might be reduced.
LCA can also be used to compare the
environmental attributes of products.
A key requirement is that products
compared are functionally equivalent.
Consider for instance, an
interior wall of a house. Such
a wall can be constructed
either using steel or wood
framing.
Careful analysis shows that if
steel is selected, even if it
contains an average
percentage of recycled steel,
the result is a large increase in
energy consumption and
emissions to air and water.
Interior Non-Load Bearing Wall,
Wood vs. Steel
Comparative Energy Use (GJ)
Wood
3.8
Steel*
11.5
Difference
3.0X
* 30% recycled content, the average recycled content for steel studs.
Source: Athena Sustainable Materials Institute.
Comparative Emissions in
Manufacturing Wood vs. Steel-Framed
Interior Wall
Emission/Effluent
CO2 (kg)
CO (g)
SOX (g)
NOX
(g)
Particulates (g)
VOCs (g)
Methane (g)
Wood Wall
,305
2,450
400
1,150
100
390
,4
,
Steel Wall
965
11,800
3,700
1,800
335
1,800
45
Difference
3.2X
4.8X
9.3X
1.6X
3.4X
4.6X
11.1X
Source: Athena Sustainable Materials Institute.
Comparative Effluents in Manufacturing
Wood vs. Steel-Framed Interior Wall
Emission/Effluent
Suspended solids (g)
Non-ferrous metals (mg)
Cyanide (mg)
Phenols (mg)
Ammonia (mg)
Halogenated
organics (mg)
Oil and grease (mg)
Sulphides (mg)
Wood Wall
Steel Wall Difference
12,180
62
99
17,715
1,310
495,640
2,532
4,051
725,994
53,665
41X
41X
41X
41X
41X
507
1,421
13
20,758
58,222
507
41X
41X
39X
Source: Athena Sustainable Materials Institute.
Careful examination can provide
surprising results . . . high impacts
linked to seemingly minor product
components, intuitively benign raw
materials, and even recycling
activity.
Use of LCA is the only way to
determine environmental impacts
with any certainty.
Summary
• Environmental laws and enforcement are not
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uniform worldwide. N. America has high
environmental standards, some regions notably
otherwise.
Certification programs provide assurance of
environmental responsibility for forest products.
The procurement of all raw materials and
manufacture of all products results in
environmental impacts.
Determination of environmental preferability
based on opinion or intuition is notoriously
unreliable.
Summary
• Life cycle analysis provides a systematic way to
•
•
determine environmental impacts.
LCA is used today by companies to identify
components and manufacturing operations
associated with the greatest environmental
impacts – and as a basis for reducing impacts.
LCA can also be used as a basis for comparing
functionally equivalent products.