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Streamlined LCA of paper towel end of life options for UBC SEEDS : recycling vs. composting Brennek, Helen; Gardner, Landon; Song, Sizhe Dec 3, 2012

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UBC Social Ecological Economic Development Studies (SEEDS) Student Report       Streamlined LCA of Paper Towel End of Life Options for UBC SEEDS Recycling vs. Composting Helen Brennek, Landon Gardner, Sizhe Song  University of British Columbia CEEN 523 December 3, 2012           Disclaimer: “UBC SEEDS provides students with the opportunity to share the findings of their studies, as well as their opinions, conclusions and recommendations with the UBC community. The reader should bear in mind that this is a student project/report and is not an official document of UBC. Furthermore readers should bear in mind that these reports may not reflect the current status of activities at UBC. We urge you to contact the research persons mentioned in a report or the SEEDS Coordinator about the current status of the subject matter of a project/report”.  Streamlined LCA of Paper Towel End of Life Options for UBC SEEDSRecycling vs. Compostingby Helen Brennek, Landon Gardner, and Sizhe SongCEEN 523: Energy and the EnvironmentPrepared for: Dr. Xiaotao (Tony) BiSubmitted: December 3, 2012iiExecutive SummaryThis study was performed for the University of British Columbia Alma Mater Society (AMS) as part of the SustainableEcological Economic Development (SEEDs) program. Although paper towel is proven to be an environmentally damagingmethod for drying hands, relative to other methods such as hand dryers, many buildings on the UBC campus must stillprovide paper towel for technical or sanitary reasons (Gregory, 2011). In particular, the AMS is concerned with how tominimize the environmental footprint of paper towels used in the Student Union Building (SUB). This streamlined LCAprovides a comparison between end-of-life options for paper towel used in SUB bathrooms, in particular for recyclingand composting.  The study used a closed loop process for recycling, and an open process with avoided burdens forcomposting. Overall it was determined that when considering impact categories of solid waste, electricity use, waterdepletion, fossil fuel depletion, climate change, and human toxicity, composting is the better option for all categoriesexcept for electricity consumption. Avoided b dens calculated to not change this result  r example, th  limateChange impact for Recycling was 1,039 kg CO q while for composting it was 734 kg CO q  (874 kg CO q  withoutavoided burdens). Additionally, a basic life cycle cost analysis was completed, and composting costs to the university areless than those for recycling.  Annual costs for composting were estimated at $5,070, while those for recycling were$16,120.iiiTable of ContentsExecutive Summary................................................................................................................................................................. ii1 Introduction .................................................................................................................................................................... 11.1 Background ............................................................................................................................................................. 11.1.1 Recycling ......................................................................................................................................................... 11.1.2 Composting ..................................................................................................................................................... 22 Goal and Scope ............................................................................................................................................................... 22.1 Functional Unit........................................................................................................................................................ 22.1.1 Impact Categories ........................................................................................................................................... 32.1.2 System Boundary ............................................................................................................................................ 32.1.3 Sources of Data ............................................................................................................................................... 53 Method............................................................................................................................................................................ 53.1 Manufacturing......................................................................................................................................................... 53.2 Transportation ........................................................................................................................................................ 63.3 Use .......................................................................................................................................................................... 63.4 Disposal ................................................................................................................................................................... 63.4.1 Option 1: Recycling ......................................................................................................................................... 63.4.2 Option 2: Composting ..................................................................................................................................... 74 Life Cycle Inventory......................................................................................................................................................... 94.1 Paper Towel Manufacturing through Recycling...................................................................................................... 94.2 Transportation ......................................................................................................................................................114.3 Disposal Options ...................................................................................................................................................114.3.1 Recycling .......................................................................................................................................................114.3.2 Compost ........................................................................................................................................................114.3.3 Comparison ...................................................................................................................................................154.4 Allocation Discussions........................................................................................................................................... 154.4.1 Recycling Process Emission Allocation.......................................................................................................... 154.4.2 Compost Process Emission Allocation .......................................................................................................... 16iv5 Impact Assessment .......................................................................................................................................................166 Life Cycle Cost ...............................................................................................................................................................207 Interpretation................................................................................................................................................................228 Conclusion and Recommendations...............................................................................................................................248.1 Conclusion.............................................................................................................................................................248.2 Recommendations ................................................................................................................................................248.2.1 Decreasing UBC’s Footprint ..........................................................................................................................248.2.2 Decreasing Paper Towel Consumption on Campus ......................................................................................248.2.3 Further Analyses ........................................................................................................................................... 259 Works Cited................................................................................................................................................................... 269.1 APPENDIX A: Network Diagram ............................................................................................................................289.1.1 Compost ........................................................................................................................................................289.1.2 Recycling .......................................................................................................................................................299.2 APPENDIX B: Electricity Composition for Quebec Electricity ................................................................................319.3 APPENDIX C: LCI for Complete System .................................................................................................................329.3.1 Recycling LCI..................................................................................................................................................329.3.2 Composting LCI .............................................................................................................................................3211 IntroductionThis Life Cycle Assessment compared disposal methods for paper towel used in the Student Union Building at theUniversity of British Columbia. The project was completed for the UBC Sustainability Office as part of the SustainableEcological Economic Development Studies (SEEDS) Program. Recycling and composting options were considered. Theassessment framework can be seen in Figure 1.Figure 1.The Life Cycle Assessment framework (International Organization for Standardization, 2006).Despite paper towels being an environmentally costly method of drying hands in campus bathrooms, for sanitary andtechnical reasons, most bathrooms must still make them available at the very least to allow users to avoid touchingbathroom doors on the way out. In order to decrease the negative impacts associated with paper towel use, the AlmaMater Society (AMS) proposed this LCA comparison.1.1 Background1.1.1 RecyclingRecycling involves several processes. The system considered in this study takes in wood chips which must be heated tohigh temperatures in water and chemicals, and blended to break it down into pulp. Paper towels to be recycled comeinto the system and are shredded, then soaked in water and chemicals in order to break them down into pulp as well.The two pulp streams are combined, with the wood chip pulp having a higher quality fibre content. The pulp mixture isthen poured onto flat screens on a conveyor. Water drains through the screens and the mixture begins to dry. The fibresbegin to bond together to form a sheet. The sheet passes through rollers to squeeze out more moisture. Heated rollers2complete the drying process, and the finished paper product is wound around rolls in preparation for packaging (TheLeading Technical Association for the Worldwide Pulp, Paper, and Converting industry, 2001).1.1.2 CompostingComposting in this report refers to the facilitated process of organic material decay. This study considers emissions froman aerated static pile facility with biofiltration, where organic material is mixed to optimal moisture content and thencovered for an extended period of time. During the decay period, a vacuum pulls air down through the p  whichoxygenates the natural decay reactions occurring. As organic materials decay in contact with oxygen, CO nd organiccompounds are emitted (Harvest Power, 2012).2 Goal and ScopeThe purpose of this Life Cycle Assessment was to compare the environmental impacts of two different paper toweldisposal options: composting, and recycling.  The study was performed to aid UBC SEEDS in their paper towel recyclingprojects, with a focus on paper towel use in the Student Union Building (SUB) bathrooms.The goal of this study is to propose recommendations regarding the best end-of-life option for paper towels in SUBbathrooms, and to produce further recommendations for UBC regarding opportunities to decrease environmental costsof paper towel use on campus. The study focused on the following major components of the paper towel life cycle:1. Production of the type of paper towel currently used in the SUB2. Transportation between the university and production or disposal facilities3. Energy usage in disposal options4. Emissions during disposal processesThis simplified LCA will examine the emissions due to each process to determine whether recycling or composting is themore environmentally friendly disposal method.2.1 Functional UnitThis study requires that a functional unit be selected to provide equivalency between the two disposal systems for directcomparison. The exact quantity of paper towel which is disposed of specifically in SUB bathrooms is unknown, but anexact purchased quantity is easily accessible. The difference between these two quantities is equal to the amount ofpaper towel dispensed in SUB bathrooms, but thrown out in a different location (for example, if someone carries thepaper towel out of the bathroom and throws it in a cafeteria garbage bin). Assuming that the proportion of paper towelordered for the SUB but disposed of elsewhere is constant, the quantity disposed of in the SUB will be directlyproportional to the quantity ordered. Therefore the functional unit used was per tonne of paper towels purchased.32.1.1 Impact CategoriesThis assessment will focus on the following indicators, as required by the AMS (UBC Alma Mater Society (AMS), 2008):1. Global Warming Potential (kg CO2 eq)2. Electricity (kWh)3. Solids waste (kg)4. Water resource depletion (m5. Cost ($)Additionally, the following impact categories were calculated.1. Human toxicity (kg 1,4-DB eq)2. Fossil fuel resource depletion (kg oil eq)Eutrophication, ecotoxicity, and biodiversity will be left out of this analysis, but should be considered for future workand decision making.2.1.2 System BoundaryThe boundaries for this LCA will begin with the production of the recycled paper towels of the type ordered by the AMSfor the SUB. They will end with the completion of the recycling or composting process. For recycling, this will be whenthe paper towel has been processed into a new usable paper product. For composting this will be when the paper hasfully degraded into compost that can be used as fertilizer. The simplified system boundary diagram can be seen in Figure2.5Paper towel currently used at the SUB contains 100% recycled content. Therefore, production of priorvirgin forms of the material (including land use change) has been left out of the LCA according to bestpractices for open loop recycling (Clift, 2012). However, the impacts of this should be considered infuture studies and will be discussed on a high level in this paper. Impacts of building, construction, andinfrastructure requirements for processing and shipping have also been omitted but should be examinedin future studies. Landfill as a disposal option was also scoped out because it is unlikely to be chosen bythe AMS as UBC strives to be waste neutral.2.1.3 Sources of DataThe information assessed was found on SimaPro using the Ecoinvent database (2007). Furtherinformation and clarification was compared through various journal articles, and other reports wherereferenced. The SimaPro software made notes on unit processes and full LCI.The following were gathered from interviews with current and potential suppliers:1. Paper towel manufacturing through recycling2. Composting energy consumptionThe following were taken from SimaPro:1. Electricity use2. Fuel use3. Truck and train transportation intensity4. Recycling process impactsThe following were taken from journal articles and estimates of inventory intensity:1. Use phase2. Composting emissions3 Method3.1 ManufacturingThe paper towel used in SUB bathrooms is 100% recycled content (Cook, 2012). Therefore, impactcategory values for the upstream portion of the LCA were determined using a generic paper recyclingprocess in SimaPro. The software assumed paper input materials to be a free stream, allocating novalues to the transportation of the wood.  However, the supplier indicated that 20% of materials were6post-industrial, so additional raw material (waste wood chips) streams were added (Cook, 2012). Themajor energy inputs included fossil fuels for machinery and electricity using the Quebec supply mix,since the paper towel is produced in Gatineau. The manufacturer indicated that the amount of materialin the packaging is equal to approximately 2.3% of the paper towel mass, so this value was used toattribute manufacture of a small mass of corrugate (Cook, 2012).3.2 TransportationIt was assumed that paper travelling from Quebec would be shipped by train to a rail depot in Delta, andthen driven by truck to the university. To complete the cycle, the used paper towel would also betransported by truck from the university either back to the Gatineau recycling facility or to the majorlocal organics composting facility (depending on the alternative being analysed). Transportationemissions were determined in SimaPro by applying the emissions per tonne-kilometre for each type oftransport to the appropriate distances travelled, and multiplying by one tonne (as per the functionalunit).3.3 UseUse emissions were minimal as no electricity is required at the time of use. Bin liners, dispensers, anddisposal bins were considered. However, due to the much longer useful life of the dispensers and binscompared to the paper towels (a decade as opposed to a day), emissions from these aspects werenegligible. Liners also have no emissions during the use phase, but their manufacture contributed a smallamount to upstream emissions.3.4 Disposal3.4.1 Option 1: RecyclingBecause paper towel coming into UBC is composed of recycled content, a loop was assumed wherein theemissions due to recycling disposal are included in the recycling emissions generated when the paper isproduced. A diagram illustrating the complete process can be seen in Figure 3.9Paper is composed mainly of wood fibres, which means that ring the lifetime of the tree, carbon wassequestered and stored in the cellulose fibres. Therefore, CO missions are negated by thesequestration that occurs throughout the life of the tree, and the decay that occurs in mposting isconsidered carbon neutral. For this reason no contribution of paper mass decay to CO missions wasincluded.However, because the compost heap is a complex system in which t  presence of paper towel willcontribute to the decay of other materials, emissions other than CO ad to be taken into consideration,particularly those of VOCs. Gray, Rosenfeld, and Sellew (2004) give detailed VOC emissionconcentrations for an aerated static pile with biofiltration, which is the type of facility located outside ofVancouver (Harvest Power, 2012). Both the study and the local composting site claim to keep the mixfractions optimized for minimal emissions and fast decay so it was concluded that the study values couldbe scaled to predict the required values. This scaling is detailed in Section 4.3.2.The emission quantities and mass flow were used to create a generic composting process in SimaPro. Inorder to apply the burdens avoided by replacing fertilizer with compost, a stream was created for themass of fertilizer replaced by 1 tonne of paper towel.4 Life Cycle InventoryData was assessed for the LCA of Paper towel upstream processes and two end-of-life scenarios. Theemissions values used are detailed in this section4.1 Paper Towel Manufacturing through RecyclingThe paper towel used at UBC is 100% recycled content where 80% is post-consumer waste (such asoffice paper) and 20% is post-industrial waste (Cook, 2012). Therefore, the inputs for the processincluded 80% post-consumer mixed paper and 20% post-industrial waste wood chips. The post-consumer mixed paper was considered to be 100% recycled paper towel (as a result, no deinking ofpaper was considered in the recycling process), and the 20% post industrial waste wood chips wereconsidered as an allocated waste stream from wood processing. The recycling process including massbalances can be seen in Figure 5 below. Note that a closed-loop process is used, which assumes thatpaper towel from UBC is returned to the recycling facility for reprocessing.23a raw material the impacts would have been different.The normalized impact demonstrates the relative importance of impacts. Human health emissions fromthis process are higher than relative impacts of climate change and fossil fuel depletion (water depletionhas no normalization factor for the software methodology used, and was therefore left out ofnormalization).  However, the normalization impacts are without weighting, so if UBC has a preferencefor climate change reductions over health impacts a weighted decision matrix would need to beconstructed to find the most important variable.Compost does output more emissions than is reported in the impact categories; about 300 kg per 1.25 tdry mass of compost produced. It also releases very small amounts of methane.  However, as discussedin Section 3.4.2, these emissions are not considered a greenhouse gas as they are biogenic emissions.They are naturally produced and were sequestered over the lifetime of the tree.To reduce the climate change impact of the manufacturing process, the amount of natural gas requiredin the re-pulping stage of recycling would need to be reduced.  New chemical processes developed to re-pulp in low temperature water baths or other innovative ideas (solar heaters?) would need to beinvented.Human toxicity impact is a major impact throughout the system due largely to transportation emissions.This impact is also due to natural gas consumption and chemical use in the paper towel productionprocess.Water consumption is linked directly to the re-pulping process of paper towel.  Recycled water streamsor processes requiring less water would reduce the water depletion potential for paper towelmanufacturing. It should be noted that there are approximately 1.56 tonnes of water within thecompost mix for 1 t of paper towel. However, the water enters the stream as moisture content in thewet compost mix (as wet compost must represent 68% of the compost mix with paper towel). Althoughthe water flows through the system, it is not considered consumed because it is waste water within theorganics stream.The electricity used and solid waste produced is difficult to mitigate.  Electricity use is likely to decreaseover time with efficiency increases, and as technology improves solid waste is likely to decrease as well.248 Conclusion and Recommendations8.1 ConclusionComposting is the best option for many reasons. It scored lower on the vast majority of impactcategories and requires less intensive sorting than recycling. It scored lower on water consumption,climate change, fossil fuel depletion and human health impact; compost was slightly higher in electricityconsumption and even for solid waste disposal (as compost production is not a waste but aninput).Therefore, not only are the overall impacts lower for the paper towel that goes to compost, butmore of the paper towel can be allowed to go to compost than if recycling were used, decreasingemissions due to unfit paper towel being sent to the landfill.8.2 Recommendations8.2.1 Decreasing UBC’s FootprintComposting has great potential to aid UBC as it strives to become a waste-neutral campus. Althoughrecycling is a viable option, it still requires significant material and energy inputs. Therefore, UBC cangreatly decrease its environmental footprint by diverting as much waste as possible from recycling andlandfill facilities by sending them to be composted. To increase the viability of composting by decreasingcontamination, specially marked clear bins should be located in bathrooms to allow for separatedisposal.Additionally, because UBC is a very large potential client for any supplier, it has substantial buyingpower. One way to use this power to positively impact the environment is through EnvironmentalProduct Declarations (EPDs). EPDs are essentially purchasing standards that must be met by any supp rthat would like to have the university as a client. For example, a limit could be established for the COemissions per case of paper towel purchased, and a potential supplier would have to provide datashowing that the emissions for his or her product are below the limit. If the university were to developrequired EPDs for its suppliers, this would encourage companies to track, quantify, and potentiallydecrease their environmental footprints for products sold to UBC.8.2.2 Decreasing Paper Towel Consumption on Campus8.2.2.1 Paper Towel used for Hand DryingIn order to avoid paper towel use on campus, it is important that UBC provide electric hand dryers in allnew buildings, and in older buildings where the electrical system permits it. Additionally, in bathroomswith electric dryers where paper towel is provided as a barrier between newly washed hands and the25bathroom door handle, paper towel dispensers should be near doors, not near sinks, and clear binsshould be provided directly underneath to make proper disposal easy. Alternatively, a less absorbentmaterial could be provided to dissuade people from using it to dry their hands. It would be important toinclude some sort of diagram or sign indicating what the material is for, and to consider the life cycleimpacts of the alternate material.8.2.2.2 Paper Towel used for Opening DoorsAirport-style doorways where a bend substitutes for a door should be planned for all new buildings oncampus so no paper towel is required for door handles. Doors in older buildings should be propped openwherever it is appropriate and possible to do so. Lastly, providing hand sanitizer just outside ofbathroom doors could substitute for paper towel used for opening doors.8.2.3 Further AnalysesIt was discovered in this study that because the AMS requires paper towel in the SUB to be 100%recycled content, which is very uncommon, the nearest recycling facility that can provide it is in Quebec.It is advisable that an LCA be performed comparing paper towel with a lower recycled content that couldbe produced locally to the current scenario to determine whether bringing in paper towel from over4000 km away cancels the benefit of the higher recycled content. Using a local manufacturer coulddecrease greenhouse gas emissions from production by up to 33%.Further analysis of the LCA should also include discussions on what the avoided burden of compost is. Inparticular, an examination of what products compost may be replacing (other than fertilizer) whichwould otherwise require raw material would be prudent. A more in-depth investigation could alsoinclude the percentage of recovery of paper towel as a recyclable material in comparison to paper towelas a compostable material. Such an analysis could also examine the percentage of paper towel inrecycling that is actually used in recycling compared with that which is intentionally diverted to compostdue to low grade wood fiber (as decided by the recycling plant).269 Works CitedAllen, J. (2012, November 27). Carbon addition to composting. (L. Gardner, Interviewer)Clift, R. (2012, October 30). Methodological issues in LCA [Lecture slides]. CEEN 523: Energy and theEnvironment. Vancouver, BC, Canada.Cook, P. (2012, November 16). UBC Paper Towel. (L. Gardner, Interviewer)Ecoinvent Centre 2007. (2007). Ecoinvent data v2.0. Ecoinvent reports No. 1-25. Dubendorf, Switzerland:Swiss Centre for Life Cycle Inventories. Retrieved from www.ecoinvent.orgGoogle, Inc. (2012, November 16). Richmond, BC to Gatineau, QC. Retrieved from Google Maps:https://maps.google.ca/maps?saddr=Vancouver,+BC&daddr=49.7030183,-112.7673405+to:48.58687,-89.8509374+to:gatineau,+QC&hl=en&sll=47.279229,-99.404297&sspn=22.583821,63.28125&geocode=Faqq7wIdOW6p-CmzT6lD8XOGVDGL84Gb6paRuw%3BFWpo9gIdlE5H-Skllonx4YZuUzHhHFoY9Google, Inc. (2012, November 17). UBC to Harvest Power, Richmond, BC. Retrieved from Google Maps:https://maps.google.ca/maps?saddr=Wesbrook+Mall&daddr=BC-99+S&hl=en&sll=49.177608,-123.100777&sspn=0.042474,0.123596&geocode=FRa77wId9W6n-A%3BFRmQ7gIdnGyp-A&oq=vancouver&mra=dme&mrsp=1&sz=14&t=m&z=14Google, Inc. (2012, November 18). UBC to Richmond, BC. Retrieved from Google Maps:https://maps.google.ca/maps?saddr=vancouver&daddr=BC-91+S&hl=en&sll=49.183948,-123.077087&sspn=0.169876,0.494385&geocode=Faqq7wIdOW6p-CmzT6lD8XOGVDGL84Gb6paRuw%3BFfxK7gIdz-ar-A&mra=dme&mrsp=1&sz=12&t=m&z=12Gray, M., Rosenfeld, P., & Sellew, P. (2004). Measurement of Biosolids Compost Odor Emissions from aWindrow, Static Pile, and Biofilter. Water Environment Research, 76(4), 310-315.Gregory, J. K. (2011). Life cycle assessment of hand drying systems. Cambridge: Massachusetts Instituteof Technology.Grubel, H. (2003). Recycling solid waste is a waste. Vancouver: Simon Fraser University.Harvest Power. (2012). Capabilities. Retrieved October 20, 2012, from Harvest: Power of we:http://www.harvestpower.com/bc/technology/27International Organization for Standardization. (2006). ISO 14040: Environmental management - lifecycle assessment. Geneva: ISO.Manji, A. S. (2012, October 31). Paper Towel Consumption at the SUB. (H. G. Brennek, Interviewer)Pfeiffer, E. (1984). How much compost should we use? Bio-dynamics. Retrieved from Bio-dynamicfarming and gardening association, Inc.Premier Tech Home and Garden. (2012). CIL Garden Fertilizer 8-8-8. Retrieved November 30, 2012, fromPremier Tech Home and Garden: http://www.pthomeandgarden.com/product/68-garden-fertilizer-8-8-8Roxby, L. (2012, November 27). Comparison with Gore claims. (L. Gardner, Interviewer)Shelton, J. (1997). Using municipal solid waste compost. Soil facts.The Leading Technical Association for the Worldwide Pulp, Paper, and Converting industry. (2001). Howis paper recycled? Earth Answers. Retrieved November 10, 2012, from www.tappi.orgUBC Alma Mater Society (AMS). (2008). AMS Lighter Footprint Strategy. Vancouver: The University ofBritish Columbia.

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