Design for the Environment/Worldwide Package Cushioning
This page is part of the Design for the Environment course
The following is a comparative Life Cycle Analysis (LCA) of three materials used in loose-fill package cushioning applications on a worldwide scale. Our hypothetical client is any major parcel delivery service (i.e. UPS, FedEx, DHL), and the current baseline is Expanded Polystyrene (EPS) foam peanuts. The first alternative is Recycled Paper (RP) shreds, available in blends of recycled/unrecycled paper products (i.e. 50/50, 80/20) in addition to purely recycled newspaper shreds. The second alternative is Starch-based polymer (SbP) foam peanuts, available in pure starch blends, or PLA-based composites. Each product’s entire lifecycle will be analyzed from an environmental assessment perspective, and will ultimately lead to a final recommendation for the most optimal package cushioning material solution. This recommendation will be dependent not only on environmental benefits, but feasibility of worldwide implementation after considering cost and relative product performance.
Project Summary
editSection 1: Group A7
Name | Wikiversity ID | Role |
---|---|---|
Brendan Cochrane | BC | Team Leader |
Jemin Hwangbo | hwangboj | Expanded Polystyrene Foam |
Regina Park | regina87611 | Recycled Paper |
Brandon Chong | Brandon_C | Starch-based Polymer Foam |
DISCLAIMER: All major Wiki components were sent to BC in wiki-code form within a Microsoft Word document from all three group members via email (primarily due to coding inefficiencies, such as difficulties repeating wiki-code of similar tables). BC sequentially updated this article as group members sent in their respective parts. Once completed, group members were then asked to openly edit the combined effort of the group. Please excuse the confusion as the majority of edits were conducted by BC - they are not representative of the equal contribution by all group members.
Highlights and Recommendations
editTo effectively summarize results, the work of Graedel’s (pictured right) Streamlined LCA (SLCA) [1] was customized into a Complete Environmental Analysis category. For this category, the following original guidelines were used:
PRODUCT MATRIX ELEMENT: 1,1
Life Stage: Cradle-to-Grave
Environmental Stressor: Complete Environmental Analysis
If either of the following conditions applies, the matrix element rating is 0:
- For the case where materials are manufactured: Metals from virgin ores are used, creating substantial waste rock residues that could be avoided by the use of suitably available recycled material. Non-renewable, threatened resources are used, with little or no effort in minimizing resource usage. Harsh, toxic chemicals are used, with little or no effort in minimizing chemical usage.
- During processing of manufactured materials: large amounts of energy are consumed when less-energy intensive manufacturing processes are readily available.
- During use of manufactured materials: Material readily degrades, unintentionally migrating harsh chemicals into their surrounding environment.
- During disposal of manufactured materials: Less than 1% of total material production is recycled. Current disposal methods are irresponsible with respect to decomposition timeframes or chemical compositions of produced materials.
- Throughout the entire life-cycle: little or no effort is being made to reduce environmental impacts by manufacturing sources (high cost is not an acceptable reason).
- EIOLCA Analysis:
- Total (Summation) Conventional Air Pollutants Released > 10 mt
- Total Global Warming Potential > 5000 MTCO2E
- Total Energy Consumption > 100 TJ
- Total Toxic Releases > 20,000 kg
- SLCA Analysis: Material receives a R(ERP) of less than 50
If all of the following conditions apply, the matrix element rating is 4:
- For the case where materials are manufactured: No environmental damage results from resource extraction or during production of materials by recycling (example: petroleum).
- During processing of manufactured materials: small amounts of energy are consumed; less-energy intensive manufacturing processes are readily investigated and implemented.
- During use of manufactured materials: Material experiences no degradation, or degradation results in a release of no toxic/harsh chemicals or materials into the environment.
- During disposal of manufactured materials: 100% of all produced material is easily recycled or composted.
- Throughout the entire life-cycle: strong effort has being made to reduce environmental impacts by manufacturing sources.
- EIOLCA Analysis:
- Total (Summation) Conventional Air Pollutants Released < 10 mt
- Total Global Warming Potential < 5000 MTCO2E
- Total Energy Consumption < 100 TJ
- Total Toxic Releases < 20,000 kg
- SLCA Analysis: Material receives a R(ERP) of more than 75
If neither of the preceding ratings is assigned, complete the checklist below. Assign a rating of 1,2, or 3 depending on the degree to which the product meets DFE preferences for this matrix element.
- Is the product designed to minimize the use of materials whose extraction or purification involves the production of large amounts of virgin materials, or non-renewable, depleting resources?
- Is the product designed to minimize the use of materials whose extraction or purification involves the production of harsh chemicals/toxics?
- Have efforts been made to optimize material production methods?
- Is material diversity minimized?
- Are future areas of research focused on environmentally-related topics?
- Can the material meet prescribed EIOLCA guideline scores within the next 10-15 years?
- Can the material meet prescribed the SLCA Environmentally Responsible Product Rating within the next 10-15 years?
In addition to this customized SLCA, a Feasibility Factor was applied with respect to meeting global demand:
Feasibility Factor
Factor | |
---|---|
Currently feasible, immediate implementation possible | 1.0 |
Feasible within 1-2 years | 0.75 |
Feasible within 5-10 years | 0.5 |
Feasible within 10-15 years | 0.25 |
Unfeasible | 0.0 |
Cradle-to-grave SLCA weighted results
editCradle-to-grave SLCA | Feasibility | Weighted Total | |
---|---|---|---|
EPS Score | 1 | 1.0 | 1.0 |
RP Score | 3 | 1.0 | 3.0 |
SbP Score | 4 | 0.5 | 2.0 |
Recommendation
editOn the 26th day of March, 2009, MIE315S Group A7 formally recommended Recycled Paper package cushioning as an immediate, readily available alternative to current baseline solution Expanded Polystyrene Foam.
It is with strong optimism that Starch-based Polymer Foam will become the future solution, but due to its current infeasibility of meeting worldwide demand, such a recommendation would be irresponsible – despite overwhelming environmental benefits.
Functional Analysis
editExpanded Polystyrene Foam
editAs EPS is the current baseline solution, any alternatives should aim to match or exceed EPS’ material properties:
Material Properties of Polystyrene [2]
Property | Value |
---|---|
Density of EPS | 25-200 kg/m³ |
Thermal conductivity (k) | 0.08 W/(m•K) |
Elongation at break | 3–4% |
Notch test | 2–5 kJ/m² |
Glass temperature | 95 °C |
Melting point | 240 °C |
Heat transfer coefficient (Q) | 0.17 W/(m2K) |
Linear expansion coefficient (a) | 8x10-5 /K |
Specific heat (c) | 1.3 kJ/(kg•K) |
Water absorption (ASTM) | 0.03–0.1 |
Decomposition | X years, still decaying |
Recycled Paper
editDensity of Paper Types [3]
Paper Grades | Density (kg/m3) |
---|---|
Unbleached Kraft | 581.3 – 692.0 |
Corrugated Medium | 609.0 |
News/Catalogue/Directory | 609.0 – 692.0 |
Pulp Sheet | 692.0 |
Fine Paper | 775.0 |
Cost of Paper Types [4]
Type | Function | Price |
---|---|---|
Shredded Newspaper Cushioning | Loose packing material in shipping crates/cartons, packing irregular shaped items, dishes, glass, plastic, furniture, books | $0.30/lb |
Recycled News paper | Inexpensive multi-purpose material | $0.30/lb |
Crinkle Cut Crimped Paper Shred | Loose packing material in shipping crates/cartons, packing irregular shaped items, dishes, glass, plastic, furniture, books | $1.55/lb |
Corrugated Rolls | Industrial padding/packing, separating items, wrapping cylindrical shapes, and protecting cabinets/furniture | $2.83/lb |
Shredded Tissue Paper | Attractive "nest" protecting merchandise | $2.88/lb |
Single Faced Corrugated Pads | Industrial padding/packing, separating items | $5.77/lb |
Starch-based Polymer Foam
editMaterial properties of Starch-based Foam [5]
Property | Value |
---|---|
Density | 230 kg/m3 |
Compressive Modulus | 1.2 MPa |
Compressive Strength | 0.13 MPa |
Functional Summary
editEach of the three package cushioning materials offers unique advantages and disadvantages. EPS offers tried-and-true material properties; as evident by its current use worldwide. Recycled paper is known to be weaker, but due to its low cost, this material weakness can be offset by simply compressing more paper shreds within a package. Starch-based polymers are largely in development; however, current generation starch-based polymers approach EPS material properties, classifying them as a suitable replacement [6].
EIOLCA
editExpanded Polystyrene Foam
editIrrelevant items in the following hybrid EIOLCA model have been set to 0 and Foam product manufacturing has been set to the sum of their values (sector 326110 to sector 33999A have been set to zero; summation added to sector 3261A0 – Foam product manufacturing). For example, input of Cutting tool and machine tool accessory manufacturing sector is now zero and the number, 1.096000 is added to foam manufacturing. This may cause some inaccuracy since heavy-duty cutting/machine tools may have been used somewhere along, but considering the relative ease of cutting EPS, its use would have been very limited.
Hybrid EIOLCA, Economic Activity [7]
Sector | Total Economic $mill | Value Added $mill | Direct Economic $mill | Direct Economic % |
---|---|---|---|---|
Total for all sectors | 2.82 | 0.988 | 1.77 | 62.8 |
Plastics material and resin manufacturing | 1.08 | 0.248 | 1.06 | 98.3 |
Other basic organic chemical manufacturing | 0.254 | 0.053 | 0.186 | 73.2 |
Petroleum refineries | 0.158 | 0.015 | 0.083 | 52.1 |
Foam product manufacturing | 0.153 | 0.053 | 0.152 | 99.7 |
Oil and gas extraction | 0.150 | 0.060 | 0.018 | 12.3 |
Top 3 sectors are Plastics material and resin manufacturing, Other basic organic chemical manufacturing and Petroleum refineries. Plastic material and resin manufacturing sector is containing overall economic activities of general plastic manufacturing (this sector contains itself in economic input analysis which is a wrong interpretation of system). Organic chemical manufacturing involves in producing number of additives that are added to polystyrene. [8]
Hybrid EIOLCA, Conventional Air Pollutants [9]
Sector | SO2 mt | CO mt | NOx mt | VOC mt | Lead mt | PM10 mt |
---|---|---|---|---|---|---|
Total for all sectors | 2.85 | 7.51 | 2.45 | 5.04 | 0.000 | 0.410 |
Power generation and supply | 1.89 | 0.093 | 0.852 | 0.008 | 0 | 0.040 |
Petrochemical manufacturing | 0.337 | 0.108 | 0.254 | 0.801 | 0 | 0.019 |
Petroleum refineries | 0.180 | 0.104 | 0.041 | 0.144 | 0 | 0.018 |
Oil and gas extraction | 0.146 | 0.248 | 0.109 | 0.167 | 0 | 0.005 |
Other basic inorganic chemical manufacturing | 0.070 | 0.007 | 0.005 | 0.004 | 0 | 0.004 |
Manufacturing Styrofoam produces a lot of air pollutants, as evident above. The major pollutants are from power generations (especially coal power plants), as manufacturing plastic foam is an energy intensive process [10]. Extracting and refining oil also uses conventional fuel such as gasoline which creates a SOx, NOx and CO in the process of combustion [11].
Hybrid EIOLCA, Greenhouse Gases [12]
Sector | GWP MTCO2E | CO2 MTCO2E | CH4 MTCO2E | N2O MTCO2E | CFCs MTCO2E |
---|---|---|---|---|---|
Total for all sectors | 1660 | 1340 | 214 | 82.6 | 20.3 |
Plastics material and resin manufacturing | 402.0 | 402.0 | 0 | 0 | 0 |
Power generation and supply | 348.0 | 343.0 | 0 | 0 | 4.18 |
Other basic organic chemical manufacturing | 141.0 | 97.0 | 0 | 44.1 | 0 |
Oil and gas extraction | 140 | 23.5 | 116.0 | 0 | 0 |
Petroleum refineries | 111.0 | 110 | 0.611 | 0 | 0 |
Green house gas is also produce when high level of energy is required. As mentioned above, plastic manufacturing sector is repeating itself. Power generation is also pointing coal power plants which produce a lot of CO2 in the reaction of coal and oxygen. Note that CO2 takes the major role in green house gas which means that most of the green house gas is from burning of conventional fuel [13].
Hybrid EIOLCA, Energy [14]
Sector | Total TJ | Elec MkWh | Coal TJ | NatGas TJ | LPG TJ | MotGas TJ | Distillate TJ | Kero TJ | JetFuel TJ | Residual TJ |
---|---|---|---|---|---|---|---|---|---|---|
Total for all sectors | 22.8 | 0.894 | 4.30 | 13.8 | 1.69 | 0.414 | 0.953 | 0.000 | 0.208 | 0.423 |
Plastics material and resin manufacturing | 7.98 | 0.437 | 0.514 | 6.44 | 0.372 | 0.095 | 0.028 | 0 | 0 | 0.050 |
Power generation and supply | 4.12 | 0.000 | 3.27 | 0.730 | 0 | 0 | 0 | 0 | 0 | 0.125 |
Petroleum refineries | 2.06 | 0.038 | 0 | 0.999 | 0.933 | 0.007 | 0.006 | 0 | 0 | 0.074 |
Petrochemical manufacturing | 1.78 | 0.038 | 0 | 1.61 | 0.100 | 0.018 | 0.005 | 0 | 0 | 0.006 |
Other basic organic chemical manufacturing | 1.74 | 0.109 | 0.274 | 1.24 | 0.076 | 0.015 | 0.004 | 0 | 0 | 0.014 |
Again, plastic manufacturing repeats itself. Power generation and supply shows the initial energy input to produce energy such as electricity to run gas turbine. Refining oil uses a lot of energy too because we have to heat the oil to really high temperature to vaporize oil and cool to liquidify [15].
Hybrid EIOLCA, Toxic Releases [16]
Sector | Non-Point Air kg | Point Air kg | Tot Air Releases kg | Water Releases | Land Releases kg | U’ground Releases kg | Total Releases kg | POTW Transfers kg | Offsite Transfers kg | Total Rel/Trans kg |
---|---|---|---|---|---|---|---|---|---|---|
Total for all sectors | 278 | 623 | 901 | 113 | 107 | 387 | 1510 | 424 | 107 | 2040 |
Plastics material and resin manufacturing | 128 | 278 | 407.0 | 30.3 | 1.64 | 148.0 | 587.0 | 242.0 | 35.6 | 864.0 |
Foam product manufacturing | 62.0 | 112.0 | 174.0 | 0 | 0.776 | 0 | 175.0 | 0.010 | 0.732 | 176.0 |
Other basic organic chemical manufacturing | 30.9 | 52.6 | 83.6 | 31.3 | 1.81 | 89.2 | 206.0 | 71.2 | 26.4 | 304.0 |
Petrochemical manufacturing | 27.7 | 38.7 | 66.4 | 27.4 | 1.56 | 93.9 | 189.0 | 76.7 | 29.0 | 295.0 |
Petroleum refineries | 9.39 | 14.1 | 23.5 | 8.89 | 0.478 | 1.11 | 33.9 | 1.77 | 1.79 | 37.5 |
Recycled Paper
editA custom EIOLCA model has been created for the Recycled Paper alternative, for no existing sector specifically models recycled paper. The following criteria have been used:
Recycled Paper Custom EIOLCA
Sector | Contribution |
---|---|
Paper and paperboard mills | $333,333 |
Paperboard container manufacturing | $333,333 |
Surface-coated paperboard manufacturing | $333,334 |
This custom EIOLCA model best represents recycled paper packaging for the following justification:
- "Paper and paperboard mills" accounts for the virgin materials manufactured from pulp used in a recycled/unrecycled paper blend [17].
- "Paperboard container manufacturing" accounts for the recycled/reused portion used in the blend, as this sector simply purchases produced paper, and does not produce it itself (from virgin materials) [18].
- "Surface-coated paperboard manufacturing" accounts for the recycled/reused portion of laminated cardboard used in stronger recycled paper blends (i.e. grid-based package cushioning) [19].
Custom EIOLCA, Economic Activity [20]
Sector | Total Economic $mill | Value Added $mill | Direct Economic $mill | Direct Economic % |
---|---|---|---|---|
Total for all sectors | 2.53 | 0.973 | 1.73 | 68.4 |
Paper and paperboard mills | 0.646 | 0.224 | 0.621 | 96.0 |
Paperboard container manufacturing | 0.348 | 0.097 | 0.341 | 98.2 |
Surface-coated paperboard manufacturing | 0.335 | 0.051 | 99.9 |
The top three sectors that perform the greatest economic activities are Paper and paperboard mills, Paperboard container manufacturing, and Surface-coated paperboard manufacturing. Paper and paperboard mills refer to the industry who manufactures paperboard from pulp. The paperboard container manufacturing sector manufactures the paperboard boxes/containers in custom-desired sizes. The surface-coated paperboard manufacturing sector manufactures the surface-coated paperboard in custom-desired dimensions.
Custom EIOLCA, Conventional Air Pollutants [21]
Sector | SO2 mt | CO mt | NOx mt | VOC mt | Lead mt | PM10 mt |
---|---|---|---|---|---|---|
Total for all sectors | 2.80 | 14.6 | 2.99 | 2.05 | 0.000 | 1.24 |
Power generation and supply | 1.91 | 0.094 | 0.861 | 0.008 | 0 | 0.040 |
Paper and paperboard mills | 0.245 | 1.65 | 0.347 | 0.133 | 0 | 0.182 |
Paperboard container manufacturing | 0.132 | 0 | 0.001 | 0 | 0 | 0 |
The top three sectors that produce the most conventional air pollutants are Power generation and supply, Paperboard container manufacturing, and Paper and paperboard mills. The total amount of air pollutants for Power generation and supply sector is 2.913 metric tonnes, for Paper and paperboard mills is 2.557 metric tonnes, and for Paperboard container manufacturing is 0.133 metric tonnes. It is indicated that Power generation and supply sector produce the largest amount of air pollutants since most of energy (power) is generated by burning fossil fuel which produces ozone, sulphur dioxide, NO2, particulate matter and other air pollutants [22]. These air pollutants cause acid rain and smog [23]. Paper and paperboard mills produce the second largest amount of air pollutants, because producing paper mills uses large amounts of energy, water, and wood pulp in extremely complex series of processes [24]. Paperboard container manufacturing produces the third highest total air pollutant emissions; at 5.2% of Paper and paperboard mills, this can be accounted for by this sector relying mostly on pre-manufactured paperboards rather than producing new paper from virgin materials. This number is most representative of recycled paper manufacturing, as a large portion of recycled paper is pre-manufactured, reused paper products.
Custom EIOLCA, Greenhouse Gases [25]
Sector | GWP MTCO2E | CO2 MTCO2E | CH4 MTCO2E | N2O MTCO2E | CFCs MTCO2E |
---|---|---|---|---|---|
Total for all sectors | 1460 | 1310 | 98.8 | 36.9 | 12.0 |
Paper and paperboard mills | 568.0 | 568.0 | 0 | 0 | 0 |
Power generation and supply | 351.0 | 347.0 | 0 | 0 | 4.22 |
Truck transportation | 88.9 | 87.5 | 0.136 | 1.22 | 0 |
The sectors that produce the most greenhouse gases are Paper and paperboard mills, Power generation and supply, and Truck transportation. This is because Paper and paperboard mills and Power generation and supply sectors have huge amounts of power that must be supplied and power generation creates many harmful air emissions. The Truck transportation sector also releases greenhouse gases such as carbon dioxide [26]. The most released global warming potential gas is CO2, indicating that power generation and paper processing aspects are key concerns in the recycled paper industry.
Custom EIOLCA, Energy [27]
Sector | Total TJ | Elec MkWh | Coal TJ | NatGas TJ | LPG TJ | MotGas TJ | Distillate TJ | Kero TJ | JetFuel TJ | Residual TJ |
---|---|---|---|---|---|---|---|---|---|---|
Total for all sectors | 19.2 | 0.876 | 5.81 | 8.29 | 0.402 | 0.623 | 1.18 | 0.001 | 0.210 | 1.67 |
Paper and paperboard mills | 8.77 | 0.530 | 2.23 | 4.50 | 0.064 | 0.079 | 0.059 | 0 | 0 | 1.25 |
Power generation and supply | 4.17 | 0.000 | 3.30 | 0.738 | 0 | 0 | 0 | 0 | 0 | 0.126 |
Truck transportation | 0.637 | 0.002 | 0 | 0.013 | 0.002 | 0.092 | 0.527 | 0 | 0 | 0 |
The top sectors for energy consumption are Paper and paperboard mills, Power generations and supply, and Truck transportation. The paper and paperboard mill sector consumes the largest amount of energy as shown above; it has 8.77 terajoules for Total energy consumption column, more than double the total energy consumption of Power generation and supply. As expected, this indicates that the largest contributor to energy on a per-mass basis is the unrecycled, virgin material used in recycled-blend (i.e. 50/50) paper. By minimizing the amount of unrecycled filler, total energy consumption can be simultaneously minimized. [28]
Custom EIOLCA, Toxic Releases [29]
Sector | Non-Point Air kg | Point Air kg | Tot Air Releases kg | Water Releases | Land Releases kg | U’ground Releases kg | Total Releases kg | POTW Transfers kg | Offsite Transfers kg | Total Rel/Trans kg |
---|---|---|---|---|---|---|---|---|---|---|
Total for all sectors | 63.1 | 826 | 890 | 107 | 391 | 50.5 | 1440 | 194 | 70.6 | 1700 |
Pulp mills | 24.0 | 302.0 | 326.0 | 40.6 | 28.1 | 0 | 395.0 | 92.6 | 9.47 | 497.0 |
Paper and paperboard mills | 15.0 | 408.0 | 423.0 | 46.9 | 28.1 | 0 | 395.0 | 92.6 | 9.47 | 497.0 |
Other basic organic chemical manufacturing | 4.16 | 7.08 | 11.2 | 4.21 | 0.243 | 12.0 | 27.7 | 9.58 | 3.56 | 40.8 |
Starch-based Polymer Foam
editA hybrid EIOLCA model has been created for the Starch-based polymer alternative, for the existing sector that best models starch-based polymers, Cellulosic organic fiber manufacturing, requires some manual modifications to remove all ties to petroleum. To do so, the following sectors were manually set to zero:
- Petroleum refineries
- Petroleum lubricating oil and grease manufacturing
- All other petroleum and coal products manufacturing
- Petrochemical manufacturing
Hybrid EIOLCA, Economic Activity [30]
Sector | Total Economic $mill | Value Added $mill | Direct Economic $mill | Direct Economic % |
---|---|---|---|---|
Total for all sectors | 2.06 | 0.919 | 1.47 | 71.4 |
Cellulosic organic fiber manufacturing | 1.00 | 0.400 | 1.00 | 100.0 |
Other basic organic chemical manufacturing | 0.180 | 0.038 | 0.140 | 77.4 |
Management of companies and enterprises | 0.111 | 0.078 | 0.082 |
Hybrid EIOLCA, Conventional Air Pollutants [31]
Sector | SO2 mt | CO mt | NOx mt | VOC mt | Lead mt | PM10 mt |
---|---|---|---|---|---|---|
Total for all sectors | 1.44 | 5.04 | 1.30 | 0.995 | 0.000 | 0.358 |
Power generation and supply | 1.21 | 0.060 | 0.548 | 0.005 | 0 | 0.026 |
Other basic inorganic chemical manufacturing | 0.050 | 0.005 | 0.003 | 0.003 | 0 | 0.003 |
Synthetic dye and pigment manufacturing | 0.021 | 0.039 | 0.002 | 0.005 | 0 | 0.002 |
Paper and paperboard mills | 0.020 | 0.134 | 0.028 | 0.011 | 0 | 0.015 |
Power generation and supply has the highest SO2 (1.21 mtCO2Eq) and NOx (0.548 mtCO2Eq) emissions. This makes sense because a substantial amount of power and supply are needed for the production of biodegradable starch-based polymers. For example if combustion is the main source of power generation then it is quite obvious that the by-products that are emitted react with the atmosphere creating the conventional air pollutants [32]. Paper and paperboard mills have the highest CO (0.134 mtCO2Eq) and VOC (0.011 mtCO2Eq) emissions. This makes sense because there are various processes that paper or paperboard must go through before completion [33]. These processes such as refiners, steam-heated rollers and machine rollers, emit pollutants that are CO and VOC or react with the air/atmosphere creating CO and VOC w:Fourdrinier_Machine. Both Power generation and supply and paper and paperboard mills have the highest PM10 emissions accounting for a sum of 0.041 mtCO2Eq, which is about 11% of the total PM10 for all sectors. These two sectors contribute quite a bit to the total PM10 emissions. This makes sense because of the particulates that most likely derive from combustion of fuels, high pressure devices, and the very small wood particles that most likely are airborne [34], [35]. Inorganic chemical manufacturing is quite low, and this makes sense because we are dealing with an organic biodegradable polymer. It appears that power generation and supply contribute to the emission of many pollutants. This makes sense because lots of energy and supplies are needed to produce the biodegradable starch-based polymer w:Fourdrinier_Machine.
Hybrid EIOLCA, Greenhouse Gases [36]
Sector | GWP MTCO2E | CO2 MTCO2E | CH4 MTCO2E | N2O MTCO2E | CFCs MTCO2E |
---|---|---|---|---|---|
Total for all sectors | 3310 | 3190 | 46.6 | 56.2 | 16.0 |
Cellulosic organic fiber manufacturing | 2670 | 2670 | 0 | 0 | 0 |
Power generation and supply | 223.0 | 221.0 | 0 | 0 | 2.69 |
Other basic organic chemical manufacturing | 100 | 69.0 | 0 | 31.3 | 0 |
Cellulosic organic fiber manufacturing has the highest GWP (Global Warming Potential) and CO2 emissions, 2670 mtCO2Eq. This certainly makes sense since this is the central sector where the starch-based polymer is actually manufactured. All the reactions of the chemicals that go into making this starch-based polymer have various by-products and as a result have the highest GWP and CO2 emissions [37]. Truck transportation is the only sector that contributes to CH4, with an emission of 0.057 mtCO2Eq. This sector also contributes 0.510 mtCO2Eq to N2O emissions, which is not a significant amount, but none the less, still negative effect for the environment. The exhaust fumes that come from the trucks react with the atmosphere producing sulfur dioxide and methane gas [38]. Power generation and supply seem to be the only sector that contributes to CFC emissions. This sector emits 2.69 mtCO2Eq most likely due to the refrigeration systems to keep starch sources (such as corn, wheat and potatoes) cool, thus preventing them from premature spoiling w:Chlorofluorocarbon#Chloro_fluoro_carbon_compounds_.28CFC.2C_HCFC.29.
Custom EIOLCA, Energy [39]
Sector | Total TJ | Elec MkWh | Coal TJ | NatGas TJ | LPG TJ | MotGas TJ | Distillate TJ | Kero TJ | JetFuel TJ | Residual TJ |
---|---|---|---|---|---|---|---|---|---|---|
Total for all sectors | 60.1 | 0.676 | 2.66 | 47.0 | 2.78 | 0.229 | 0.680 | 0.000 | 0.152 | 5.88 |
Cellulosic organic fiber manufacturing | 5.24 | 0.372 | 0 | 43.6 | 2.70 | 0.011 | 0.061 | 0 | 0 | 5.61 |
Power generation and supply | 2.65 | 0.000 | 2.10 | 0.470 | 0 | 0 | 0 | 0 | 0 | 0.080 |
Other basic organic chemical manufacturing | 1.24 | 0.078 | 0.195 | 0.879 | 0.054 | 0.010 | 0.003 | 0 | 0 | 0.010 |
Cellulosic organic fiber manufacturing is by far the highest energy consumption sector, with a total consumption of 52.4 TJ of the total 60.1 TJ. This makes sense because this is the main process in which starch-based polymers are created. Cellulosic organic fibre manufacturing emits the most energy and this should be true because this is the most important step in creating the starch-based polymer [40].
Custom EIOLCA, Toxic Releases [41]
Sector | Non-Point Air kg | Point Air kg | Tot Air Releases kg | Water Releases | Land Releases kg | U’ground Releases kg | Total Releases kg | POTW Transfers kg | Offsite Transfers kg | Total Rel/Trans kg |
---|---|---|---|---|---|---|---|---|---|---|
Total for all sectors | 1000 | 13400 | 14400 | 222 | 968 | 105 | 15700 | 97.0 | 54.9 | 15900 |
Cellulosic organic fiber manufacturing | 958.0 | 13200 | 14200 | 180 | 663.0 | 0 | 15000 | 0.766 | 3.01 | 15000 |
Other basic organic chemical manufacturing | 22.0 | 37.4 | 59.4 | 22.3 | 1.29 | 63.5 | 146.0 | 50.7 | 18.8 | 216.0 |
Plastics material and resin manufacturing | 5.90 | 12.8 | 18.7 | 1.39 | 0.075 | 6.81 | 26.9 | 11.1 | 1.63 | 39.3 |
Cellulosic organic fiber manufacturing is the leading sector in highest total air releases of toxic substances. Since this is the sector that emits the most energy then it makes sense that this sector releases the most in total releases. Due to all the chemical processes and machinery involved into producing the starch-based polymer, it is inevitable that toxic substances will be released into the air, especially with this sector using the most energy [42], [43], w:Chlorofluorocarbon#Chloro_fluoro_carbon_compounds_.28CFC.2C_HCFC.29.
SLCA
editStreamlined or Semi-Quantitative Life Cycle Analysis (SLCA) is a qualitative LCA that makes use of a defined scoring system. Following Graedel’s scoring guidelines, an analyzed product (or process) may be assigned a score of 0 to 4 for each matrix element, as defined below. A score of 0 indicates a harmful environmental impact with little or no effort to investigate less environmentally-damaging alternative. A score of 4 indicates little or no environmental impact. If a score of 0 or 4 is unrepresentative of the product’s environmental impact for a designated life stage, an intermediate score is assigned – the mentioned guidelines are used to initiate discussion; ultimately leading to a score of 1, 2 or 3 [44].
Results
editPremanufacturing
editPS exhibits a significantly lower total score than RP or SbP primarily due to the origins of PS’ main ingredient, petroleum [45]. The environmental damage caused by the extraction of petroleum is well-documented; directly impacting PS’ scores for Materials Choice, Solid and Liquid Residue categories. Gaseous residues produced an interesting result: RP was assigned a score of 0 due to the large amount of coal-refinery dependent pulp processing required for the non-recycled portion of RP blends (i.e. 50/50) [46]. SbP also scored poorly, due to concerns over the harvesting of starch sources via machine-based farming and processing. While petroleum processing is responsible for considerable gaseous releases, there is no way for the PS industry to minimize the use of those materials, and thus a score of 0 is not acceptable, as recommended by Graedel.
Manufacturing
editPS finishes with the highest total in the manufacturing life-stage and most notably the best score in the Energy Use category. While PS production indeed uses appreciable amounts of energy, no other less energy-intensive method is available. However, for both RP and SbP, less-energy intensive methods are available, but are not deployed. Another interesting category is Liquid Residues, where PS achieves a score of 4, far better than RP and SbP’s scores of 1 and 0, respectively. During PS production, negligible liquid residues are produced; the process simply involves the mixing of melted PS resins [47]. RP requires significant chemical usage during the treatment of pulp and recycled products [48]. SbP requires large use of chemical solvents to isolate polymers (i.e. polylactic acid) within target crops/starch sources [49].
Delivery
editMinor scoring differences are attributed to the water-sensitive properties of RP and SbP. Therefore, water-resistant packaging (i.e. polyethylene) must be used whereas PS is water-resistant in its produced state. However, packaging contributions as a whole is small due to the very low density of these package cushioning products, and thus all three products score well throughout this life-stage [50].
Use
editSole source of a major scoring difference is present in the Materials Choice category. Prolonged animal exposure to PS is known to cause cancer, whereas exposure with humans can cause problems with the central nervous system, have neurotoxic effects (fatigue, nervousness, difficulty sleeping) and can be carcinogenic [51]. Prolonged exposure to PS fumes among human females is known to cause menstrual disorders and metabolic disturbances during pregnancy [52]. RP and SbP exhibit no harmful properties, and thus are awarded scores of 4 versus PS’ score of 0.
Minor solid residues are expected from PS – styrene migration is known to be as high as 0.025% under normal use [53]. While small, this migration factor of non-biodegradable styrene is still present, and thus a score a 4 cannot be awarded. While similar migration factors can be expected for RP and SbP, the small amount can be readily consumed by micro-organisms. Thus, a score of 4 is appropriate [54].
Disposal
editSole source of a major scoring difference is present in the Materials Choice category. Prolonged animal exposure to PS is known to cause cancer, whereas exposure with humans can cause problems with the central nervous system, have neurotoxic effects (fatigue, nervousness, difficulty sleeping) and can be carcinogenic [55]. Prolonged exposure to PS fumes among human females is known to cause menstrual disorders and metabolic disturbances during pregnancy [56]. RP and SbP exhibit no harmful properties, and thus are awarded scores of 4 versus PS’ score of 0. Minor solid residues are expected from PS – styrene migration is known to be as high as 0.025% under normal use [57]. While small, this migration factor of non-biodegradable styrene is still present, and thus a score a 4 cannot be awarded. While similar migration factors can be expected for RP and SbP, the small amount can be readily consumed by micro-organisms. Thus, a score of 4 is appropriate [58].
Summary
editThe purpose of a SLCA analysis is to better provide a quantifiable score to qualitative discussion. The final result of a SLCA analysis is the Environmentally Responsible Product Rating (R(ERP)).
The RERP is a summation of each matrix element score, from 0 to 4, for each product. A maximum score of 100 indicates little or no environmental impact throughout the entire life of the analyzed product. A minimum score of 0 indicates significant environmental impact.
R(ERP) Results
Product | Rating |
---|---|
Polystyrene Foam | 54 |
Recycled Paper | 70 |
Starch-based Polymer Foam | 76 |
As evident from discussion distribution above, the five SLCA categories do not appear to reflect an equal weight within the analysis of package cushioning products. Manufacturing, Delivery and Use life-stages should not bear equal weight with such a disposal-intensive industry. Additionally, the source of these packaging materials is of significant concern, and in the opinion of the authors, is not accurately represented. With that said, a custom weighted SLCA analysis is proposed, with the following weights attributed to each life-stage:
Weighted SLCA
Life-stage | Original Weight | Custom Weight |
---|---|---|
Premanufacturing | 1.0 | 1.25 |
Manufacturing | 1.0 | 0.75 |
Use | 1.0 | 0.5 |
Delivery | 1.0 | 0.5 |
Disposal | 1.0 | 2.0 |
The corresponding weighted R(ERP) results are determined to be:
Weighted R(ERP) Results
Product | Rating |
---|---|
Polystyrene Foam | 42 |
Recycled Paper | 67.75 |
Starch-based Polymer Foam | 79.5 |
When comparing standard versus weighted results, both analyses award Starch-based Polymers as the most environmentally responsible rating, albeit more drastic in the weighted results. Recycled paper experiences a drop of 2.25 points, indicating slightly poorer performance in the life-stages that were determined to count. Polystyrene foam experiences a significant decrease of 22%, and is more accurately punished for its environmentally-damaging disposal methods.
Cost Analysis
editIt is becoming increasingly evident that polystyrene is not the most environmentally-friendly solution. Recycled paper has continuously displayed significant benefits throughout its life-cycle. Starch-based polymers are showing near-unanimously positive results, arguably the front runner at this point. Before making a final recommendation, the economic trade-offs must be weighed against the potential environmental benefits. The purpose of this report is to recommend a feasible solution that may one day replace the current baseline polystyrene solution. This goal is only possible if the recommendation makes not only environmental sense, but economic sense as well.
Direct Costs
editDirect costs of a product include the capital, operating and disposal costs associated throughout the entire life of the product. Unfortunately, the availability of detailed costing reports remains mostly within private companies; however, approximate estimations were made using openly available data.
Expanded Polystyrene Foam
editThe price for expandable polystyrene is around 1000 US dollars per ton in the market. Price for expanded polystyrene (moulded, steamed beads) is around 1500 to 2000 US dollars. Considering its density, EPS normalizes to 60-200 US dollars per cubic meter (depending on the complexity of its shape) [59]. This value can decrease even more with peanut forms because of a lower density due to many more EPS cavities being filled by air. Raw materials such as petroleum and other additives are used to produce polystyrene. As of March 22, 2009, crude oil price in current market is 52 US dollars per barrel (117.3 litres) [60], not much different from solid polystyrene itself. Large-scale plastic manufactures make small beads of polystyrene particles with higher densities and ship it to packaging manufacturers. This strategy reduces the cost of shipment, due to a lower, more compacted shipping volume. Then, the packaging manufacturers put them in a mould and use steam to grow the beads to desirable size.
Recycled Paper
editThe current cost for 24m3 of used paper is $4000 USD [61]. Equipment required in a typical medium-scale recycled paper manufacturing company includes 20 industrial paper shredder machines at $11,995 USD each, or $239,900 USD total [62]. A single industrial steam boiler at $46,850 USD [63] is required in addition to an attached waste water treatment unit at $25,000 USD [64]. An industrial paper milling machine valued at $280,000 USD is required to produce the final recycled paper blend [65]. Using the known dimensions of required machinery, a medium-scale recycled paper manufacturing operation would require approximately 19,510 ft2 of floor space. Industrial floor space in Mississauga, Ontario currently rents for an annual net cost of $5.95/ft2 [66]. Thus, for 19,510 ft2 of industrial spacing, it will cost $1,160,845.50 per year. A simple summation of known machinery energy usage values yields an estimated total of 200kWh. At $0.062 per kWh for electricity usage in Ontario, a 24-hour operating facility will consume approximately $297.60 of energy per day. Additionally, labour is required to keep the plant in operation. At a rough estimate of 50 workers in the factory at any given time, and a rough estimate of $25/hour for general unskilled labour (as given in MIE341: Computer Aided Design), $30,000/day of labour can be expected. The production line of the used newspaper shred consists of paper milling, cutting and packing. The major pollutant release would be coming out of paper milling stage and shipping; carbon dioxide is going to be emitted as power generator and truck are used. Possible indirect environmental cost can take place due to the greenhouse gas emission. However, newspaper shred is 100% recycled product which bring positive impact to environment. For other recycled paper cushioning package product such as fibreboard pads usually is only 50% recycled. This is because it is necessary to add virgin fibre to the pulp to compensate for the retirement of degraded fibre; fibre is typically degraded and unusable after five to seven cycles [67].
Starch-based Polymer Foam
editThe price for biodegradable starch based foam peanuts is $1.50/ft3 quoted by Puffy Stuff. The estimated capital cost would be between $9,808,240 - $12,260,300 CDN to establish a modern starch factory [68]. Export prices are currently around $225/tonne for cassava starch from Thailand [69] – this will be used as our transportation costs. Main components for manufacturing starch-based foam peanuts include a Boiling water bath, valued at $1,495 USD [70], which is used to boil starch sources in preparation for processing. Next, a screw extruder device is required to combine boiled starch and treatment chemicals (including solvents) in raw polymer form. A single-screw food extruder is valued at $1,995 USD [71]. Finally, a compression moulding machine is required to reach a near-net shape of our final product, where it will then be packaged and shipped. An aluminum compression moulding machine is valued at $19,000 USD [72]. To match current industry rates at which foam is being produced, our facility needs to extrude starch-based polymers at a rate of 1000lb/hr [73]. To meet such a demand, a medium scale manufacturing facility, similar to the size as proposed for a recycled paper plant, is most appropriate. Therefore, an annual rent cost of $1,160,845.50, $30,000/day of labour and $297.60 of energy per day can be expected. As expected, disposal costs of starch-based polymer foam are non-existent, as it is 100% biodegradable. Once shipped, our cost analysis ends – there is no need to worry about future green tax penalties or concerns over land-fill space [74].
Direct Costs Summary
editOn an annual production basis of 1,000,000 kg of material per year, the following estimated production costs for a medium scale factory are (using the above information):
Manufacturing Operation Costs
Material | Cost (millions US) |
---|---|
EPS Foam | $2.191 |
Recycled Paper (loose-fill) | $1.774 |
Starch-based Polymer Foam | $13.699 |
As expected, Recycled Paper is the cheapest packaging material to produce on a medium-scale basis.
Indirect Costs
editIndirect costs of a product include the environmental, health, and social costs associated throughout the entire life of the product.
Expanded Polystyrene Foam
editMajor indirect costs arise from recently discovered health issues. The negative effects of polystyrene on human health increases health care cost which affects the total cost of producing Styrofoam for the society. It is known that long exposure to polystyrene can cause neurotoxic (fatigue, nervousness, difficulty sleeping), hematological (low platelet and hemoglobin values), cytogenetic (chromosomal and lymphatic abnormalities), and carcinogenic effects [75]. It is now classified as Group 2B substance (possibly carcinogenic to humans) by international Agency for research on Cancer. Many animal tests revealed that it causes cancer to number of animals even though no tests have been taken place for human yet [76]. Accumulation of this material can cause the impairment of the nervous system and damage brain and spinal cord [77]. The main health problem occurs to the workers who are exposed to the polystyrene vapour. Vapour can easily move to the lung and absorbed by human bodies. A Russian study of 110 women exposed to polystyrene vapour shows that polystyrene causes menstrual problem disrupting menstrual cycle and causing hypermenorrhea [78]. Misusage of polystyrene containers can cause serious problems as well. Polystyrene can be broken down easily in contact with acidic substance (such as lemon to your tea), Vitamin A, and high temperature [79]. Even without such chemicals, polystyrene can be dissolved in water and consumed by human. If a person drinks beverages from polystyrene cups four times a day for three years, he may have consumed one cup worth of polystyrene [80].
Recycled Paper
editOne of the indirect environmental costs is due to the greenhouse gas that is emitted from the coal burning power generation used in the paper mill. In U.S., it is reported that the 4th largest contributor to greenhouse gas emissions is the paper industry which also contributes 9% of the manufacturing sector's carbon emissions [81]. The newspaper shred is one of paper-made cushioning packaging materials that are 100% recycled product which brings positive impact to environment. Compared to un-recycled products, 100% recycled paper content product production consumes 44% less energy, produces 38% less greenhouse gas emissions, 50% less wastewater, 41% less particulate emissions and 49% less solid waste [82]. However, 100% recycling paper usage is not the case for other recycled paper cushioning package product such as fibreboard pad which often is only 50% recycled [83]. This is because it is necessary to add virgin fibre to the pulp to compensate for the retirement of degraded fibre; fibre is typically degraded and unusable after five to seven cycles [84]. This means fresh trees needed to be cut to supply the demand of virgin fibre by the fibreboard pad sector of industry. One of major environmental costs is due to the deforestation resulted from logging. Logging destroys natural habitats causing the loss of biodiversity that ultimately leads to the local – and possibly global – extinction of species [85]. Logging also brings damages to the soil since logging accelerates erosion, weathering and humus decomposition which lead to widespread formation of soils with low nutrient [86]. Change in climate due to the logging also brings negative impacts to environment. When the forest cover gets removed, immediate change in precipitation occurs because of the change in transpiration. This results in a greater intensity of rainfall around the logging region causing run-off and erosion of soil [87].
Starch-based Polymer Foam
editUsing starch based biodegradable polymers (BP) for packaging foam appears to be a great idea. It is made from renewable resources, such as rice, corn, wheat, and potatoes, and it is 100% biodegradable [88]. So the question that arises is: Are there any negative things about this type of foam? Using these foods for other purposes, such as producing foam, definitely proposes many issues. Food production will be less for everyone, therefore prices will go up. For well developed countries, it will not be too bad, due to the fact that they can afford it. But for third world countries, spending more money on food is not an option because they simply do not have the money for that. For US to meet current output of biodegradable polymers would require 1.62 m2/kg produced [89]. This is quite a lot when we are talking about at least 68 million kg of BP’s are being produced in the year 2001. This number is even higher now in 2009 [90]. When agricultural crops are grown, they may involve the application of fertilizers, pesticides, and herbicides which could leave an environmental impact. If soil managements practices are not undertaken, the soil risks severe depletion of nutrients, microorganisms etc. To add to that, chemical or biochemical processes usually are done to extract and purify the polymer. These processes will require energy, water, and biological and chemical additives/solvents. They also produce wastes which definitely require appropriate treatment and disposal. [91]