Environmental Life Cycle Analysis by patrickoquinn

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									              Environmental Life Cycle
                    Assessment




                      Firoz Jameel, Jesse Daystar and Richard A. Venditti*
                            Department of Wood and Paper Science
                                North Carolina State University
                                    Raleigh, NC 27695-8005

                                   *Corresponding author:
                          Richard_Venditti@ncsu.edu, (919) 515-6185
LCA: General Definition   LCA Procedure   Paper Recycling   Housing   Bioethanol   Review   1
                               Introduction

         Learning Objectives of this section:

         a) Be able to define a LCA
         b) To understand an LCA’s importance
         c) To identify important aspects of an LCA




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                                   Sustainability?

    •   How do we supply societies needs without harming the environment or
        future generations’ ability to meet their needs?

    •   We have many options to meet our demands.

    •   How to choose the “best” option?

    •   Life cycle assessment helps to inform our choices.




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LCA: General Definition   LCA Procedure   Paper Recycling   Housing   Bioethanol   Review
             What is a Life Cycle Assessment ?

      Life Cycle Assessment (LCA) is a tool to assess the potential
      environmental impacts of products, systems, or services at all stages
      in their life cycle [ISO 14001:2004].


      Types of LCA

            •Cradle to Gate: raw materials to finished good (no use or end
                life considerations)

            •Cradle to Grave: Considers everything from harvesting
                materials to the disposal of the finished goods




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LCA: General Definition   LCA Procedure   Paper Recycling   Housing   Bioethanol   Review
                             Example LCA Process
                                                   Recycled Materials

   Energy                      Energy
                                                Energy                     Energy                  Energy




    Raw
                          Production           Transportation                Use                Disposal
  Materials
                                                                                                Recycle

                      Waste                   Waste                        Waste
    Waste
                                                                                              Waste
                              Emissions to                                    Emissions to
                              air and water            Emissions to                                Emissions to
                                                       air and water          air and water        air and water




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                          Why is an LCA Important?

       • Helps ensure compliance with government regulations
       • Helps decrease the environmental impact of a given product
           - Identifies ways to improve sustainability
           - Identifies ways to “green” all aspects of product’s life
       • Can reshape company strategy
       • Can help marketing
           - Can reshape company image
           - Develop product advantage of competition




LCA: General Definition    LCA Procedure   Paper Recycling   Housing   Bioethanol   Review   6
                 Important Aspects of Life Cycle
                          Assessment

                          Goal and Scope
                            Definition




                     Inventory Analysis                        Interpretation




                    Impact Assessment




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LCA: General Definition     LCA Procedure   Paper Recycling   Housing   Bioethanol   Review
                Goal and Scope Definition


         Learning Objectives of this section:

         a) To understand how to properly define the
            goals of an LCA

         b) To understand how to establish the
            boundaries of an LCA




LCA: General Definition   LCA Procedure   Paper Recycling   Housing   Bioethanol   Review   8
                                    Defining Goals

    •   Should state the intent of the study
         – Intended application
         – Intended use
         – Intended audience
    •   Should also include reason for the study




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LCA: General Definition   LCA Procedure   Paper Recycling   Housing   Bioethanol   Review
                                   Defining Scope

    •   Define functional unit of product
    •   Help establish system boundaries for the LCA
    •   Determine data collection methods




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LCA: General Definition   LCA Procedure   Paper Recycling   Housing   Bioethanol   Review
          Goal and Scope Definition: Your Turn

     Exercise: Define the goal and scope of an LCA designed
         to study the life cycle of a peanut butter and jelly
                               sandwich




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LCA: General Definition   LCA Procedure   Paper Recycling   Housing   Bioethanol   Review
                 Important Aspects of Life Cycle
                          Assessment

                          Goal and Scope
                            Definition




                     Inventory Analysis                        Interpretation




                    Impact Assessment




LCA: General Definition     LCA Procedure   Paper Recycling   Housing   Bioethanol   Review   12
                    Inventory Analysis

         Learning Objectives of this section:

         a) To understand what needs to be included
            in an inventory analysis

         b) To understand the steps and processes
            included in an inventory analysis




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         Inventory Analysis: What Needs to be
                      Included?
    •   All relevant stages of the life of a product
          – Raw Materials/Energy Needs
          – Manufacturing
          – Transportation, Storage & Distribution
          – Use, reuse, and maintenance
          – Recycle & Waste Management

                                                                 Recycled Materials

                 Energy                   Energy
                                                             Energy                       Energy                    Energy




                  Raw
                                   Production                Transportation                   Use                Disposal
                 Materials
                                                                                                                 Recycle

                                               W                              W                   W
               W             W                 a                              a                   a
               a             a
                                   Emissions tosair                           s       Emissions tosair
               s             s                             Emissions to air
                                   and water t                                t       and water t               Emissions to air
               t             t                 e           and water
                                                                              e                   e             and water
               e             e
                                                                                                                                   14
LCA: General Definition      LCA Procedure            Paper Recycling             Housing          Bioethanol      Review
                   Inventory Analysis: Setup
    •   In an LCA, it is necessary to standardize all units of measure
    •   For measuring energy use
         – Use mega joules (MJ) to measure potential energy from non-renewable
            sources
         – Use kilowatt hours (kW-h) to measure electrical energy
    •   For measuring waste materials and emissions
         – Use tons to measure airborne emissions and solid waste
         – Use gallons or liters to measure waterborne emissions
    •   Create a standard basis for comparison
          – Example: per product piece, or per kg of product
    •   Establish rigid boundaries for the Inventory Analysis




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LCA: General Definition   LCA Procedure   Paper Recycling   Housing   Bioethanol   Review
                      Inventory Analysis:
                  Raw Materials & Energy Needs
    •   Two types of Raw Materials
         – Primary- first use material
         – Secondary- second use material (recycled)
    •   Analyze energy requirements
         – Energy required to harvest the raw materials
         – Energy required to convert the raw materials to the finished product
    •   Look at materials associated with maintaining the raw materials
    •   Define and quantify emissions and wastes associated with the production of
        the raw materials




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LCA: General Definition   LCA Procedure   Paper Recycling   Housing   Bioethanol   Review
                              Inventory Analysis:
                                Manufacturing
    •   Manufacturing should take into account the following
         – Tools
            • Molds, machinery, etc.
         – Processes
         – Waste Material
         – Packaging
         – All emissions produced
         – Energy used




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LCA: General Definition   LCA Procedure   Paper Recycling   Housing   Bioethanol   Review
                  Inventory Analysis:
        Transportation, Storage and Distribution
    •    Transportation
          – Equipment used to move goods
              • Airplanes, trucks, trains, etc
          – Distance
    •    Storage and Distribution
          – Warehouses
          – Wholesalers
          – Retailers




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LCA: General Definition   LCA Procedure   Paper Recycling   Housing   Bioethanol   Review
                         Inventory Analysis:
                    Use, Reuse and Maintenance
    Inventory or materials and energy required to fully utilize the product
    • Use
        – Energy required for normal use
        – Emissions from normal use of the product
    • Reuse
        – Reusing product for the intended purpose
        – Reusing the product in a different manner
    • Maintenance
        – Replacement parts                                           motor oil, oil &
        – Maintenance fluids                                          air filter, hoses,
            • Oils, grease, polish, paint, etc                        tires, etc.

                                             CO2, H2O
                                    spent motor oil,
                                                                                    spare parts for
                                    oil & air filter,                 gasoline      newer cars
                                    hoses, tires, etc.
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LCA: General Definition   LCA Procedure   Paper Recycling   Housing    Bioethanol   Review
                      Inventory Analysis:
                Recycle and Waste Management
    •   Recycle
         – Salvage of useful parts
         – Production of secondary raw materials
    •   Waste Management
         – Disposal of non-salvageable product
            • Landfills, hazardous waste dumps, etc
            • Incineration
            • Composting




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         Inventory Analysis: Types of Pollution

    •   Three main types of pollution
         – Airborne emissions
             • Carbon dioxide, sulfur dioxide, etc
         – Waterborne emissions
             • Wastewater, untreated chemicals, etc
         – Solid waste
             • Scrap materials, process waste, etc




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LCA: General Definition   LCA Procedure   Paper Recycling   Housing   Bioethanol   Review
                    Inventory Analysis: ISO Standard


    •   Overall steps for LCA are defined in ISO 14044
    •   Steps for conducting an inventory analysis are explained in ISO 14041
    •   Steps involved
         1. Preparing for data collection
         2. Data collection
         3. Validation of data
         4. Relating data to unit process
         5. Relating data to functional unit and data aggregation
         6. Refining system boundaries




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LCA: General Definition   LCA Procedure   Paper Recycling   Housing   Bioethanol   Review
                              Inventory Analysis:
                                   Example
    •   Example product: copy paper
    •   Raw Materials
          – Wood, water, various chemicals, energy
          – Chemical and Energy Recovery
    •   Manufacturing
          – Machinery, processes, packaging material
    •   Transportation and Distribution
          – Storage of paper in warehouses, selling of it via wholesalers/retailers
    •   Use
          – Products associated with the use of copy paper
    •   Disposal
          – Waste products, Recycling, landfilling
          – Energy recovery




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LCA: General Definition   LCA Procedure   Paper Recycling   Housing   Bioethanol   Review
                   Inventory Analysis: Your Turn

           Exercise: Conduct an Inventory Analysis of a
                 Peanut Butter and Jelly Sandwich:




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LCA: General Definition   LCA Procedure   Paper Recycling   Housing   Bioethanol   Review
                 Important Aspects of Life Cycle
                          Assessment

                          Goal and Scope
                            Definition




                     Inventory Analysis                        Interpretation




                    Impact Assessment




LCA: General Definition     LCA Procedure   Paper Recycling   Housing   Bioethanol   Review   25
                Impact Assessment
           Definition:

           Impact assessment is the process of identifying the future
              consequences of a current or proposed action. (cbd.int/impact)



         Learning Objectives of this section:

         a) To understand what needs to be included in
            an impact assessment
         b) To identify the usual steps and processes
            included in an impact assessment



LCA: General Definition   LCA Procedure   Paper Recycling   Housing   Bioethanol   Review   26
                   Impact Assessment: ISO Standard

    •   Overall steps for LCA are defined in ISO 14044
    •   Protocol for an impact assessment is explained in ISO 14042
    •   Mandatory elements for an impact assessment
         – Selection of impact categories
         – Assignment of inventory analysis results
         – Calculation of category indicator results (characterization)
    •   Optional elements
         – Calculation of the magnitude of category indicators (normalization)
         – Grouping
         – Weighting




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LCA: General Definition   LCA Procedure   Paper Recycling   Housing   Bioethanol   Review
                        Impact Assessment:
                     What Needs to be Included?
    All environmental impacts associated with the production, use and disposal of
        the product

    •   Ecological Systems Degradation
    •   Resource Depletion
    •   Human Health & Welfare




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LCA: General Definition   LCA Procedure   Paper Recycling   Housing   Bioethanol   Review
                     Impact Assessment:
                Ecological Systems Degradation
      Ecological system : An ecosystem is a natural
      unit consisting of all plants, animals and micro-
      organisms (biotic factors) in an area functioning
      together with all of the non-living physical (abiotic)
      factors of the environment. (Christopherson, 1996)


  •     Chemical
         – Toxicity
  •     Physical
         – Habitat Loss
  •     Biological
         – Foreign Species

                                           Invasive species-Kudzu

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LCA: General Definition   LCA Procedure   Paper Recycling   Housing   Bioethanol   Review
                Impact Assessment:
       Ecological Systems Degradation – Risks
                    Assessment
   •    Ecological Response to Indicator
   •    Intensity of Potential Effect
   •    Time Scale of Recovery
   •    Spatial Scale
   •    Transport Media

   There is no global agreement in weighting risks


               Cl
                                                                                          Hole in
       Cl      C          Cl                                                            ozone layer
                                                                                         caused by
                                                                                           Freon
               F
            Freon 11

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LCA: General Definition        LCA Procedure   Paper Recycling   Housing   Bioethanol    Review
        Impact Assessment: Resource Depletion

    •    Resources are either renewable or non-renewable
          – Renewable
               • Hydroelectric energy, biomass products, most crops, etc
          – Non-renewable
               • Oil, minerals, metals, etc
    •    Ideally want to recycle as many non-renewable based components as
         possible




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LCA: General Definition   LCA Procedure   Paper Recycling   Housing   Bioethanol   Review
                           Impact Assessment:
                          Human Health & Welfare
    •   Analyze impact of product on human health
         – Diseases that could potentially be caused by using the product
                • Cigarettes: Cancer
          – Diseases that can be caused by wastes produced by the product or the
            production of it
                • Solid particulates emitted in stack gasses for a coal burning plant: Cancer
    •   Products that harm human health can have a negative impact on a
        company’s image




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LCA: General Definition   LCA Procedure   Paper Recycling   Housing   Bioethanol   Review
                              Environmental Indices

            1. IGW – global warming
            2. ISF – smog formation
            3. IOD – ozone depletion
            4. IAR – acid rain
            5. IINH – human inhalation
            6. IING – ingestion toxicity
            7. ICINH -human carcinogenic inhalation
            8. ICING – carcinogenic ingestion toxicity
            9. IFT – fish toxicity




LCA: General Definition   LCA Procedure   Paper Recycling   Housing   Bioethanol   Review   33
                   Impact Assessment: Example
    •   Example product: copy paper
    •   Ecological systems degradation
         – Impact of cutting down trees
         – Impact of discharged chemicals in the
           water waste on the water quality
    •   Resource depletion
         – Resource is renewable because it is trees,
           but it is not rapidly replaceable
         – The paper is easily recyclable, reducing
           primary raw material needed
         – For energy, mostly self sufficient
    •   Human health and welfare
         – Impact of chemicals used on human
           health
         – Impact of stack emissions from chemical
           and energy recovery on health of
           population around mill
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LCA: General Definition   LCA Procedure   Paper Recycling   Housing   Bioethanol   Review
                  Impact Assessment: Your Turn

      Exercise: Conduct the impact assessment for a Peanut
                     Butter and Jelly Sandwich




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LCA: General Definition   LCA Procedure   Paper Recycling   Housing   Bioethanol   Review
                 Important Aspects of Life Cycle
                          Assessment

                          Goal and Scope
                            Definition




                     Inventory Analysis                        Interpretation




                    Impact Assessment




LCA: General Definition     LCA Procedure   Paper Recycling   Housing   Bioethanol   Review   36
                           Interpretation

         Learning Objectives of this section:

         a) To be able to identify what needs to be included in
            an interpretation
         b) To understand how this step can be best used




LCA: General Definition   LCA Procedure   Paper Recycling   Housing   Bioethanol   Review   37
                          Interpretation: ISO Standard

    •   Overall steps for LCA are defined in ISO 14044
    •   Proper protocol for interpretation is explained in ISO 14043
    •   Aside from presenting results, the interpretation should conduct these
        checks
         – Completeness check
         – Sensitivity check
         – Consistency check
    •   Include conclusions and recommendations




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LCA: General Definition    LCA Procedure   Paper Recycling   Housing   Bioethanol   Review
     Interpretation: The Feedback Mechanism

    •   Analyze opportunities to reduce or mitigate the environmental impact
        throughout the whole life cycle of a product, process or activity.
    •   Analysis may include both quantitative and qualitative measures of
        improvement
         – Changes in product design
         – Changes in raw material usage
         – Changes in industrial processes

         Original
         product




   After
   Improvement
   Analysis
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LCA: General Definition   LCA Procedure   Paper Recycling   Housing   Bioethanol   Review
                          Interpretation: Example
    •   Example product: copy paper
    •   Changes in product design
         – Determining potential areas of improvement for the product design
         – Lighter weight paper?
         – Lower brightness paper?
    •   Changes in raw materials
         – Using more secondary materials in place of primary materials
         – Use alternative chemicals
    •   Changes in industrial process
         – Changing from Acid to Alkaline papermaking
         – Changing from chlorine containing bleaching processes to chlorine free
           bleaching processes




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LCA: General Definition   LCA Procedure   Paper Recycling   Housing   Bioethanol   Review
                          Interpretation: Your Turn

      Exercise: Interpret the results of your LCA and present
                          them to the group




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LCA: General Definition   LCA Procedure   Paper Recycling   Housing   Bioethanol   Review
                          Carbon Footprint Model
         for Bleached Pulp and Paper Products




                 Trevor H. Treasure, Jesse S. Daystar and Richard A. Venditti*
                           Department of Wood and Paper Science
                                North Carolina State University
                                   Raleigh, NC 27695-8005

                                   *Corresponding author:
                          Richard_Venditti@ncsu.edu, (919) 515-6185
LCA: General Definition   LCA Procedure   Paper Recycling   Housing   Bioethanol   Review   42
                                Waste Paper
                          What do we do with it all?
    Paper
    •More than 700 lb/person annual paper
    consumption in the USA
    •40% of all municipal waste is paper

    •What should be done with waste paper?




LCA: General Definition   LCA Procedure   Paper Recycling   Housing   Bioethanol   Review   43
                               Life Cycle Assessment
                             -Recycling Paper Products

                          Goal and Scope
                            Definition




                     Inventory Analysis                        Interpretation




                    Impact Assessment




LCA: General Definition     LCA Procedure   Paper Recycling   Housing   Bioethanol   Review   44
                           Goals
                 Goal and Scope Definition

   • To compare the carbon footprint of three waste
     management scenarios for copy paper
             1. Landfilling
             2. Incineration
             3. Recycling
   • To perform a systematic and quantitative evaluation
     of these three waste management options
   • To provide a tool for consumers and waste
     management personnel for determining the best
     waste management practices

LCA: General Definition   LCA Procedure   Paper Recycling   Housing   Bioethanol   Review   45
                           Scope
                 Goal and Scope Definition

    • Three waste management scenarios considered.
          1.     Landfilling
          2.     Incinerating
          3.     Recycling

    • This study will not consider the effect of recycling on the
      value of wood or its consequences on the wood market
    • A full impact assessment will not be performed
    • This analysis only accounts for carbon emissions
    • Other significant pollutants are emitted but are not
      accounted for in this study, example heavy metals



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                          Assumptions 1 of 2

    •Increased recycle production has no effect on tree production
    •Methane emissions from land fills have been converted to carbon
    dioxide equivalents using a ratio of 21:1 (IPCC 1995, table 4, pg. 26)
    •Avoided CO2 releases based on fuel mix for national electricity grid
    •Heating value of copy paper  6213 BTU/lb (PTF White Paper No.3)
    •Net heating value of methane 21,433 BTU/lb (engineeringtoolbox.com)




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                          Assumptions 2 of 2

    •Responsible silviculture  replant to harvest ratio equals 1:1
    •Carbon sequestration based on wood makeup and weight percent
    carbon of cellulose, hemicelluloses, and lignin
    •All mills are considered to be average in energy and production
    efficiency
    •Office paper is assumed to be 20% inert, inorganic filler material
    •Office paper fibers: 20% softwood and 80% hardwood




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                               Life Cycle Assessment
                             -recycling paper products

                          Goal and Scope
                            Definition




                     Inventory Analysis                        Interpretation




                    Impact Assessment




LCA: General Definition     LCA Procedure   Paper Recycling   Housing   Bioethanol   Review   49
            Raw Material Composition
         Paper Composition                          %
         % Soft Wood                               20%
         % Hard Wood                               80%

         Component                                       Softwood Hardwood
         Cellulose                                         42%      45%
         Hemicellulose                                     27%      30%
         Lignin                                            31%      25%

         Component                                   % carbon by weight
         Major Hemicellulose - SW                            44.68%
         Minor Hemicellulose - SW                            47.31%
         Major Hemicellulose - HW                            37.76%
         Minor Hemicellulose - HW                            43.60%
         Lignin                                              60.93%

          Source: Dr. Dimitris S. Argyropoulos, course pack for WPS 332




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                             Carbon Equivalents
  •Carbon Equivalents Conversion

  `
  CO2 Tons                12 g carbon/mol
                                             =Carbon Equivalents
                          44 g CO2/mol



  Methane Tons            12 g carbon/mol
                                             =Carbon Equivalents
                          16 g CH4/mol


                                                                                    12+(4x1)=16
Methane Tons combusted 12 g carbon/mol
                                                  =Carbon Equivalents
                              16 g CH4/mol




LCA: General Definition      LCA Procedure     Paper Recycling     Housing   Bioethanol     Review   51
                Process Flow Diagram 1 of 2
                Virgin Production + Landfilling


                     Energy/fuel
                                                                 CO2 Emissions



                      Energy/fuel                                CO2 Emissions

                      Filler

                      Energy/fuel                                CO2 Emissions




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              Process Flow Diagram 1 of 2

                      Energy/fuel=0                             CO2 Emissions=0



                                                                   CO2 Emissions
                     Energy/fuel



                      Energy/fuel
                                                                        CO2 Emissions
                                                                        Methane Emissions


                                          Carbon Stored in landfill
                          Electricity production



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                            Process Conversions
   Process                                lb CO2     Per ton                     Source
   Green Wood Transportation                305    Green wood         Paper Task Force White Paper
   Virgin Production                       2995      Paper            Paper Task Force White Paper
   Transportation to Market                 33       Paper            Paper Task Force White Paper
   Collection and Landfill Equipment        84       Paper            Paper Task Force White Paper



          Landfill                         % by wieght                Source
          CO2 Landfill Emmisions             15.2%     Paper task force white papers
          Methane Landfill Emissions         22.9%     Paper task force white papers
          Carbon Sequestured                 61.9%
          Mathane Recovered                  50.0%     Assume 50% (CORRIM)
          CO2 from Methane Combustion        75.0%


                 Carbon Offset from Electrical Production                            Source
   CO2 Offset from Electrical Production 127      CO2 lbs per MMBTU       Paper Task Force White Paper
   Net BTU                               21433 BTU per lb Methane             Engineering Tool Box


              •1 ton methane is equal to 21 ton CO2 equivalents


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                       Virgin Production + Landfill
               Energy Requirements and Carbon Emissions
            Energy                                                             Emissions
            MMBTU                         UNIT PROCESS                   Ton Carbon Equivalents
                0          Tree Growth                                           -791
             1909          Tree Harvest and Transport                             139
             37913         Paper Mill                                            1418
              205          Paper Transport to Market                              4.5
               ~0          Use of Product                                          ~0
              527          Collection Vehicle & Landfill Equipment                11.5
             -1863         Landfill                                               30.5
             38690         Total                                                  812




     •Negative values represent either energy created or carbon
     sequestered




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                           Process Flow Diagram 1 of 2
                          Virgin Production + Incineration



                                                                   CO2 Emissions
                     Energy/fuel



                      Energy/fuel                                  CO2 Emissions




                      Energy/fuel                                  CO2 Emissions




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              Process Flow Diagram 2 of 2
                   Energy/fuel=0                              CO2 Emissions=0




                     Energy/fuel                                CO2 Emissions



                     Energy/fuel                               CO2 Emissions




                                                               CO2 Emissions
                                                               Methane Emissions

                                          Carbon


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              Virgin Production + Incineration
                        Calculations
                 • Incinerator carbon equivalents emissions=

                       tons carbon in wood      Virgin paper mill yield %   Fiber in paper




                 •Energy produced from paper combustion=
                 tons paper               6213 BTU       2000        1 MMBTU                  White paper #3
                                                         lbs
                 tons virgin production   lb paper       ton         1,000,000 BTU




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                     Virgin Production + Incinerate
               Energy Requirements and Carbon Emissions
              Energy                                                         Emissions
              MMBTU                       UNIT PROCESS                 Ton Carbon Equivalents
                 0           Tree Growth                                        -791
               1909          Tree Harvest and Transport                         138.6
              37913          Paper Mill                                         1418
                205          Paper Transport to Market                           4.5
                ~0           Use of Product                                      0.0
                297          Collection Vehicle & Landfill Equipment             6.5
              -11643         Incineration                                        89.0
              28680          Total                                               866




          •Negative values represent either energy created or carbon
          sequestered




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                            Process Flow Diagram 1 of 3
                          Recycled Production + Recycling
                  Energy/fuel                                  CO2 Emissions




               Energy/fuel                                      CO2 Emissions




                  Energy/fuel                                     CO2 Emissions


                  Energy/fuel
                                                                CO2 Emissions


                  Filler                                        Rejects to waste treatment


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                             Process Flow Diagram 2 of 3
                           Recycled Production + Recycling

                Energy/fuel                                   CO2 Emissions




              Energy/fuel=0                                   Carbon sequestered in product




Possible decrease in
demand
 NOTE: Tree growth loss is
 assumed to be zero for this
 study
                                                              Forest used in more profitable
                                                              ways such as construction

 LCA: General Definition    LCA Procedure   Paper Recycling    Housing   Bioethanol   Review   61
                            Process Flow Diagram 3 of 3
                          Recycled Production + Recycling


                      Energy/fuel                                      CO2 Emissions




                                                                       CO2 Emissions
                                                                       Methane Emissions




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                      Calculations
              Recycled Production + Recycle
                    Carbon sequestered in use=

                    tons carbon in wood      Virgin paper mill yield %   Tons recycled paper

                    Tons virgin production



                 Carbon sequestered in landfill=
                 tons organics
                                             (1-.382)                    Paper Task Force: White Papers
                 Filler content




                 Tons organics in sludge=
                                          Tons recycled paper      % Filler
                    Total sludge




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                     Recycled Production + Recycle
               Energy Requirements and Carbon Emissions
              Energy                                                              Emissions
              MMBTU                          UNIT PROCESS                   Ton Carbon Equivalents
                989          Recovered Paper Collection                              26.5
                283          Material Recovery Facility                              5.3
                205          Transport to Recycle Mil                                 6
               20300         Recycle Paper Mill                                      470
                205          Transportation to Market                                4.5
                 0           Use                                                    -380
                227          Collection Vehicle and Landfill Equipment               4.9
               -1133         Landfill                                                 19
               21077         Total                                                  156.1



                   •Negative values represent either energy created or carbon
                   sequestered




LCA: General Definition   LCA Procedure    Paper Recycling     Housing   Bioethanol   Review         64
                                 Unit Process Emissions

                                                  Virgin Prod. + Virgin Prod. + Recycle Prod. +
    All values are tons                           Landfill       Incinerate     Recycle

    Carbon sequestered in tree growth                       -791         -791              N/A
    Raw material acquisition                             139              139              37.3
    Paper mill production                               1418             1418              470
    Transport to market                                  4.5              4.5              4.5
    Carbon sequestered in product                          0                0             -395
    Collection and landfill equipment/ sorting            11                6              4.9
    Landfill                                            265.1             0.0              161
    Carbon sequestered in landfill                      -235                0             -143
    Incinerate                                           N/A               89              N/A
    Total Carbon Equivalents                             812              866              141
    Total Carbon Equivalents per ton                    0.812            0.866            0.141
    Total Carbon Equivalents per ton                    0.812            0.866            0.141




LCA: General Definition   LCA Procedure   Paper Recycling      Housing   Bioethanol   Review      65
                            % Difference From Landfilling


    Carbon Equivalents Emissions Comparison % Difference from Landfilling
                                               Virgin Prod. Virgin Prod. + Recycle Prod.
    Landfill reported in tons for comparison + Landfill     Incinerate     + Recycle
    Raw material acquisition                         139          0%            -73%
    Paper mill production                          1418           0%            -67%
    Collection and landfill equipment/ sorting        11         -44%           -57%
    Landfill                                         265        -100%           -39%
    Carbon sequestered in landfill                  -235        -100%           -39%
    Total Carbon Equivalents                         812          7%            -83%
    Total Carbon Equivalents per ton               0.812          7%            -83%




LCA: General Definition   LCA Procedure   Paper Recycling   Housing   Bioethanol   Review   66
                                 Sensitivity Analysis
                             Virgin Production + Landfill


     Sensitivity Analysis on Carbon Equivalents per ton for Virgin Production + Landfill
     Percent Change                         10%                -10%      % Change from base Case
     Softwood %                             0.808              0.817               0.58%
     Transportation emissions               0.828              0.797               1.90%
     Landfill methane recovery              0.763              0.862               6.12%



      •Base case value of .812 carbon equivalents per ton of production

      •Landfill methane recovery rate has the largest impact on carbon
      emissions

      •Methane is 21 times more harmful than CO2




LCA: General Definition   LCA Procedure   Paper Recycling   Housing   Bioethanol   Review      67
                                  Sensitivity Analysis
                            Virgin Production +Incinerate


    Sensitivity Analysis on Carbon Equivalents per ton for Virgin Production + Incinerate
    Percent Change                         10%               -10%      % Change from base Case
    Softwood %                            0.863             0.869                 0.35%
    Transportation emissions              0.881             0.851                 1.73%
    Landfill methane recovery             0.866             0.866                 0.00%



     •Base case value of .866 carbon equivalents per ton
     of production

     •The carbon emissions of this waste management
     practice are not greatly impacted by these sensitivities




LCA: General Definition   LCA Procedure   Paper Recycling   Housing   Bioethanol   Review        68
                                Sensitivity Analysis
                          Recycled Production + Recycling


Sensitivity Analysis on Carbon Equivalents per ton for Recycled Production + Recycle
Percent Change                         10%              -10%      % Change from base Case
Softwood %                             0.141            0.141               0.00%
Transportation emissions               0.145            0.136               2.95%
Landfill methane recovery              0.110            0.171              21.50%




      •Base case value of .141 carbon equivalents per ton of production

      •Landfill methane recovery rate has the largest impact on carbon emissions

      •Transportation emissions significantly impacted the total




LCA: General Definition   LCA Procedure   Paper Recycling   Housing   Bioethanol   Review   69
                                   Interpretation
            Waste Management Method                         ton C produced/ton paper
            Virgin Production + Landfill                              0.650
            Virgin Production + Incinerate                            0.725
            Recycle Production + Recycle                              0.207

    • The Recycling scenario has the smallest carbon footprint

    • Landfill carbon footprint is highly dependent on the methane
      recovery rate

    • Increased recycling may reduce green house gas emissions

    • Increased recycling may impact the wood market
          – These impacts are outside the scope of this study


LCA: General Definition   LCA Procedure   Paper Recycling    Housing   Bioethanol   Review   70
               Interpretation: Environmental
                Improvement Opportunities
    • Potential Process Improvement
          – Increase methane recovery in landfills
          – Decrease transportation of products and raw materials
          – Increase paper production efficiency

    • Energy
          – Use renewable transportation fuels
          – Utilize renewable electrical power
          – Increase energy efficiency in production process




LCA: General Definition   LCA Procedure   Paper Recycling   Housing   Bioethanol   Review   71
                  Wood for Building Houses
                                  An Example of LCA




                                             Adam Taylor
                                         Assistant Professor
                                    Forestry, Wildlife & Fisheries
                               203 Forestry Products, 2506 Jacob Drive
                                        Knoxville, TN 37996
                                       AdamTaylor@utk.edu
                                       Phone: 865-946-1125



LCA: General Definition   LCA Procedure   Paper Recycling   Housing   Bioethanol   Review   72
                          What Do You Think?




                                                http://www.ussi.ca/residential_steel.html
LCA: General Definition   LCA Procedure   Paper Recycling   Housing   Bioethanol   Review   73
                             Acknowledgment
    • All of the information in this presentation is
      based on work conducted by CORRIM
    • http://www.corrim.org/




LCA: General Definition   LCA Procedure   Paper Recycling   Housing   Bioethanol   Review   74
                                          CORRIM
    • Consortium for Research on Renewable
      Industrial Materials
    • Aims to provide a database of information for
      quantifying the environmental impacts and
      economic costs of building materials




LCA: General Definition   LCA Procedure   Paper Recycling   Housing   Bioethanol   Review   75
                                      Motivation
    • The environmental consequences of changes in forest
      management, product manufacturing, and construction are
      poorly understood
    • Lack of up-to-date, scientifically sound, product life-cycle data
      in the United States, particularly life-cycle data regarding
      wood and bio-based products
    • For example, concerns about the sustainability of present
      forest practices have lead to changes in forest harvesting in
      the US. As a result, the US wood products sector has lost a
      substantial market share to non-wood substitutes and foreign
      suppliers



LCA: General Definition   LCA Procedure   Paper Recycling   Housing   Bioethanol   Review   76
                          Mission: To create…
    • A consistent database to evaluate the environmental
      performance of wood and alternative materials from resource
      regeneration or extraction to end use and disposal, i.e., from
      "cradle to grave. (Figure 1).
    • A framework for evaluating life-cycle environmental and
      economic impacts.
    • Source data for many users, including resource managers,
      manufacturers, architects, engineers, environmental
      protection and energy analysts, and policy specialists.
    • An organizational framework to obtain the best science and
      peer review



LCA: General Definition   LCA Procedure   Paper Recycling   Housing   Bioethanol   Review   77
                    Membership in CORRIM
           Research Institutions and Voting Board Members
           University of Washington
           Oregon State University
           University of Minnesota
           University of Idaho
           FORINTEK, Canada
           Virginia Tech
           North Carolina State University
           Purdue University
           University of Maine
           Penn State University
           State University of New York
           APA, The Engineered Wood Association
           Western Wood Products Association
           Composite Panel Association Research Foundation
           Washington State University
           Louisiana State University
           Mississippi State University

LCA: General Definition   LCA Procedure   Paper Recycling   Housing   Bioethanol   Review   78
                              Life Cycle Assessment
                           -applied to building products

                          Goal and Scope
                            Definition




                     Inventory Analysis                        Interpretation




                    Impact Assessment




LCA: General Definition     LCA Procedure   Paper Recycling   Housing   Bioethanol   Review   79
                                            Goals
    • To develop a database and modeling system
      for environmental performance
      measurements associated with materials use

    • To respond to specific questions and issues
      related to environmental performance and the
      cost effectiveness of alternative management
      and technology strategies.


LCA: General Definition   LCA Procedure   Paper Recycling   Housing   Bioethanol   Review   80
                                            Scope
    Houses built with different materials
      • Minneapolis (cold climate) - wood &
        steel
      • Atlanta (warm climate) - wood &
        concrete




LCA: General Definition   LCA Procedure   Paper Recycling   Housing   Bioethanol   Review   81
              Minneapolis House – Front Elevation




LCA: General Definition   LCA Procedure   Paper Recycling   Housing   Bioethanol   Review   82
                      Design Differences: Minneapolis
                            Full Basement 2062 sq.ft. 2 story

             Characteristic                        Wood Design                              Steel Design
 1st and 2nd Floors                       Engineered wood “I” –joists @          Steel 18 ga. “C” joist @ 12” (300mm)
                                              16” (400mm) o/c & 19/32”                o/c & 19/32” (15mm) plywood
                                              (15mm) plywood decking                  decking

 Above grade exterior walls               2” x 6” wood studs @ 16” (400mm)       1.5” x 3.63” Steel 20 ga. “C” studs @
                                                o/c, #15 organic felt, OSB            16” (400mm) o/c, #15 organic felt,
                                                sheathing, R19 fiberglass batt        OSB sheathing, R13 fiberglass batt
                                                insulation, 6mil polyethylene         insulation, 1.5” EPS insulation,
                                                vapor barrier, 12mm gypsum            6mil polyethylene vapor barrier,
                                                board, vinyl siding                   12mm gypsum board, vinyl siding




 Below grade exterior walls               2”x4” wood studs @ 24” (600mm)         1.5” x 3.63” Steel 25 ga. “C” studs
                                              o/c, R13 fiberglass batt                @ 24” (600mm) o/c, R13
                                              insulation, poly vapor barrier,         fiberglass batt insulation, poly
                                              12mm gypsum board                       vapor barrier, 12mm gypsum
                                                                                      board

 Partition walls                          2”x4” wood studs @ 16” (400mm)         1.5” x 3.63” Steel 25 ga. “C” studs @
                                              o/c, 12mm gypsum board                  16” (400mm) o/c, 12mm gypsum
                                              two sides                               board two sides




LCA: General Definition   LCA Procedure      Paper Recycling         Housing     Bioethanol       Review                 83
                Design Differences: Atlanta
                               2153 sq.ft. 1 story On-Slab

           Characteristic                          Wood Design                            Concrete Design
Single-family dwelling type                               1 story bungalow slab-on-grade
Floor area                                                       2153 sq. ft. (200 sq.m)
Structure & Envelope
Foundation (footing and slab)                                 3000psi (20 Mpa) concrete
Foundation walls                                                              None
Main floor                                      100mm reinforced Slab-on-grade on footings
Exterior walls                            2”x4” wood studs @ 16” (400mm) o/c,     Concrete Block furred out with 2x4
                                               #15 organic felt, OSB sheathing,      wood studs 24”(600mm) o/c, R13
                                               R13 fiberglass batt insulation,       fiberglass batt insulation, 6mil poly
                                               6mil poly vapor barrier, 12mm         vapor barrier, 12mm gypsum
                                               gypsum board, vinyl siding            board, two-coat stucco finish

Window system                               PVC frame, operable, double glazed Low “E” Argon filled
Partition walls                           2”x4” wood studs @ 16” (400mm) o/c,12mm gypsum board two-sides

Roof                                      Light Frame Wood Trusses with OSB sheathing, R30 blown cellulose insulation,
                                               6mil poly vapor barrier, 16mm gypsum board with 25 yr durability asphalt
                                               shingles over #15 organic felt building paper.

LCA: General Definition   LCA Procedure       Paper Recycling       Housing       Bioethanol       Review                 84
                              Life Cycle Assessment
                           -applied to building products

                          Goal and Scope
                            Definition




                     Inventory Analysis                        Interpretation




                    Impact Assessment




LCA: General Definition     LCA Procedure   Paper Recycling   Housing   Bioethanol   Review   85
            Life Cycle Inventory Analysis for Wood
                      Building Materials

                                      Forest Management
                                        (Regeneration)
                                                       (Transportation)
                                                                                EMISSIONS
                                  Raw Material Acquisition
                                        (Harvest)                              EFFLUENTS
    MATERIALS                                          (Transportation)
                                                                               SOLID WASTES
                                   Product Manufacturing
      ENERGY                                           (Transportation)         OTHER RELEASES
                                   Building Construction
       WATER                                           (Transportation)
                                          Use/Maintenance                       PRODUCTS
                                                       (Transportation)
                                 Recycle/Waste Management                       COPRODUCTS
                                                       (Transportation)

LCA: General Definition   LCA Procedure      Paper Recycling    Housing   Bioethanol   Review    86
                              System Boundaries
                   Forest Resources: NW and SE (25-100+ years)
“Cradle”
                   Harvesting ( < 1 Year)
                              logs                      NW and SE

“Gate              Processing ( < 1 Year)
  to                                lumber    SE and NW (green and dry)
 Gate”                              plywood NW and SE
                                    OSB       SE
                                    Glulam, LVL, I-Joists

                   Construction           ( < 1 Year)

                                   wood and steel Minneapolis (cold)
                                   wood and concrete Atlanta (warm)

                   Use and Maintenance                   (40 – 100+ years)
“Grave”
                   Disposal          (< 1 Year)
LCA: General Definition   LCA Procedure      Paper Recycling     Housing     Bioethanol   Review   87
      Boundaries:               Regeneration to waste disposal
                                Primary source for wood data
                                Secondary source for non wood data (ATHENA)
                                Regional product detail
                                Multi-material detail

  Environmental                Air, water, toxic substances, energy, carbon, waste
   Performance:
                               • mid-point parameters for human health risk




     Protocol:                 Strategic Research Plan (1998)
                                 • Study Guideline (2000) – ISO consistent



LCA: General Definition   LCA Procedure   Paper Recycling   Housing   Bioethanol   Review   88
                          Building Product LCI’s

       • For building products
             – for lumber, plywood, OSB, LVL, glulam, I-joists, trusses
       •   Unit process descriptions (saw, dry, plane etc.)
       •   Mill surveys at unit process level
       •   Non-wood inputs (energy by source, raw materials)
       •   Emissions and solid waste outputs
       •   Yields, flows (co-products) and mass balances
       •   Unit factor estimates (raw materials, air, water, and solid
           emissions, energy, carbon) before and after impacts from
           purchased energy and transportation


LCA: General Definition   LCA Procedure   Paper Recycling   Housing   Bioethanol   Review   89
                    U.S. LCI Database Project
    • ATHENA & NREL
    • Publicly available info on common materials,
      products and processes
    • Could lead to “eco-impact labels”
          – similar to food labeling




LCA: General Definition   LCA Procedure   Paper Recycling   Housing   Bioethanol   Review   90
         Life-Cycle Inventory results 1.0 MSF 3/8-in. basis plywood production

                          INPUTS                                                     OUTPUTS
Materials                  Units Per MSF                          Materials           Units  Per MSF
                                 3/8-in. basis                  Bark                         3/8-in. basis
                            ft.3 6.56E+01                       Bark waste              lb.  1.31E+01
Wood/resin                  lb.   1.89E+03                      Bark ash                lb.  7.75E+00
Roundwood (log)                                                 Total                   lb.  2.09E+01
                            lb.   1.59E+01                      Products
                     a
Phenol-formaldehyde lb.           8.90E+00                      Plywood                 lb.      9.91E+02
Extender and fillers        lb.   1.11E+00                      Co-products             lb.
                                                                Wood chips              lb.      4.25E+02
Catalyst a                  lb.   3.30E-01                      Peeler core             lb.      4.62E+01
Soda ash a                  lb.   1.98E+02                      Green clippings         lb.      3.10E+01
                                                                Veneer downfall         lb.      3.44E+00
Bark b                      lb.   6.81E+00                      Panel trim              lb.      1.07E+02
Dry veneer                  lb.   1.51E+01                      Sawdust                 lb.      9.63E+00
Green veneer                                                    Solid dry veneer        lb.      6.68E+01
                                                                Total                   lb.      6.89E+02
Electrical energy                                               Air emissions
Electricity                kWh    1.39E+02                      Acetaldehyde            lb.      1.12E-02
                       b                                        Acetone                 lb.      4.80E-03
Fuel for energy                                                 Acrolein                lb.      4.95E-07
                        b lb.     3.83E+02
Hog fuel (produced)                                             Benzene                 lb.      4.77E-04
                                                                CO                      lb.      1.91E+00
Hog fuel (purchased) lb.          3.40E+01                      CO 2 fossil             lb.      2.78E+02
Wood waste                 lb.    5.00E-01                      CO 2 non-fossil         lb.      2.78E+02
Liquid propane gas         gal.   3.59E-01                      Dust (PM10)             lb.      2.08E-01
                           ft.3   1.63E+02                      Formaldehyde            lb.      1.80E-02
Natural gas                                                     Methanol                lb.      1.28E-01
Diesel                     gal.   3.95E-01                      NO x                    lb.      2.34E-01
                                                                Organic substances      lb.      2.20E-02
 a These materials were excluded based on the 2% rule.          Particulates            lb.      3.47E-01
 b Bark and hogged fuel are wet weights whereas                    Phenol               lb.      8.27E-03
 all other wood materials are oven dry weights;                 SO 2                    lb.      7.74E-04
 bark weight is included in the “hog fuel (produced)” weight.   SO x                    lb.      1.01E-01
                                                                VOC                     lb.      6.26E-01
LCA: General Definition        LCA Procedure         Paper Recycling   Housing   Bioethanol   Review         91
                              Life Cycle Assessment
                           -applied to building products

                          Goal and Scope
                            Definition




                     Inventory Analysis                        Interpretation




                    Impact Assessment




LCA: General Definition     LCA Procedure   Paper Recycling   Housing   Bioethanol   Review   92
     An example of LCI comparisons: Minneapolis
                                          Steel minus Wood
                                 Extraction (primary materials in kg)
       8,000
                                  5,595
       6,000

       4,000
                                                                                                       2,457
       2,000
                   558                             352           390          691
                                                                                                                         162
            0

      -2,000

      -4,000

      -6,000
                                                                                         -6,398
      -8,000
                Limestone (kg)   Iron Ore (kg)   Water (1000    Obsolete     Coal (kg)   Wood Fiber   Metallurgical   Prompt Scrap
                                                   liters)     Scrap Steel                  (kg)       Coal (kg)        Steel (kg)
                                                                   (kg)


LCA: General Definition      LCA Procedure              Paper Recycling        Housing      Bioethanol         Review                93
         An example of LCI comparisons : Atlanta
                                    Concrete minus Wood
                              Extraction (primary materials in kg)
       7,000                                     6,421
       6,000
       5,000
       4,000
       3,000
                    2,072
       2,000
       1,000                                                     583                       367
                                     160
            0
      -1,000
      -2,000                                                                -1,620
      -3,000
                  Limestone     Iron Ore (kg)     Fine         Obsolete Wood Fiber   Prompt
                     (kg)                       Aggregate     Scrap Steel (kg)     Scrap Steel
                                                  (kg)           (kg)                 (kg)

LCA: General Definition     LCA Procedure   Paper Recycling     Housing   Bioethanol   Review    94
                                   GWP: Minneapolis and Atlanta

                              50
                              45
                              40
        TONS CO2 Equivalent




                              35
                              30                                                                                  CH4
                              25                                                                                  N2O
                              20                                                                                  CO2
                              15
                              10
                               5
                               0
                                    Steel                 Wood              Concrete              Wood
                                            Minneapolis                                 Atlanta



LCA: General Definition              LCA Procedure        Paper Recycling     Housing      Bioethanol    Review         95
                  Summary - Minneapolis Building

                                                                                         Other Design
                                                                                         vs. Wood (%
       Minneapolis design                 Wood          Steel        Difference            Change)
   Embodied Energy (GJ)                    651          764               113                17%
         Global Warming
            Potential
             (CO2 kg)                     37,047      46,826              9,779              26%
       Air Emission Index
            (index scale)                 8,566        9,729              1,163              14%
     Water Emission Index
          (index scale)                    17            70                53               312%
            Solid Waste
              (total kg)                  13,766      13,641              -125               -1%

LCA: General Definition   LCA Procedure     Paper Recycling     Housing     Bioethanol    Review        96
                          Summary - Atlanta Building
                                                                                       Other Design vs.
                                                                                          Wood (%
             Atlanta Design               Wood         Concrete         Difference        Change)

    Embodied Energy ( GJ)                  398              461            63               16%


   Global Warming Potential
           (CO2 kg)                       21,367        28,004           6,637              31%

        Air Emission Index
             (index scale)                4,893             6,007        1,114              23%

     Water Emission Index
          (index scale)                      7               7              0                   0%
             Solid Waste
               (total kg)                 7,442         11,269           3,827              51%



LCA: General Definition   LCA Procedure   Paper Recycling     Housing     Bioethanol   Review         97
             Other Studies – Same Results
    • 1992 New Zealand study
          – Wood office building 55% of energy/70% carbon
            versus concrete
          – Steel wall 4x energy of wood wall
    • 1992, 1993 Cdn studies
          – Wood 1/3 energy and CO2 versus steel and
            concrete
    • Wood consistently lower emissions and less
      energy
LCA: General Definition   LCA Procedure   Paper Recycling   Housing   Bioethanol   Review   98
                              Life Cycle Assessment
                           -applied to building products

                          Goal and Scope
                            Definition




                     Inventory Analysis                        Interpretation




                    Impact Assessment




LCA: General Definition     LCA Procedure   Paper Recycling   Housing   Bioethanol   Review   99
                                              Not All Energy is Equal

                                          Product Manufacturing Carbon Emissions

                                    800


                                    700
      CO2: Kg/cubic meter wood eq




                                    600
                                                carbon neutral biofuel
                                    500


                                    400


                                    300


                                    200
                                                                                             fossil
                                                                                           emissions
                                    100


                                     0
                                    NW KD Lumber
                                            1         NW Plywood
                                                           2                  OSB
                                                                           SE 3               4         Concrete
                                                                                                              5
                                                                                                        floor area eq.




LCA: General Definition                            LCA Procedure         Paper Recycling      Housing     Bioethanol     Review   100
                           Emissions to Water: Minneapolis
                               Other
                               Acids                                                                             Wood
                        Other Metals
                                 Iron                                                                            Steel
                         Phosphorus
        Dissolved Organic Compounds
                   Nitrates & Nitrites
                           Sulphides
                          Sulphates
                        Oil & Grease
                 Aluminum & Alumina
                           Chlorides
               Halogenated Organics
          Non-Halogenated Organics
               Ammonia & Ammonium
                         Phosphates
                             Phenols
                             Cyanide
                 Non-Ferrous Metals
            Chemical Oxygen Demand
   Polynuclear Aromatic Hydrocarbons
                     Dissolved Solids
                   Suspended Solids
           Biological Oxygen Demand


                                         0              50000           100000        150000            200000           250000


LCA: General Definition                      LCA Procedure      Paper Recycling   Housing      Bioethanol   Review            101
                          Emissions to Water: Minneapolis
                            On Equal Health Risk Basis
          Iron
     Sulphide                                                          Wood
     Sulphate                                                          Steel
        Oil-Gr
         Alum
        Chlor
     Halo-Org
        Nitr-Al
      Phenol
           CN
     Non-Ferr
         PAH
         TDS

                  -                 20,000            40,000           60,000            80,000


LCA: General Definition    LCA Procedure   Paper Recycling   Housing   Bioethanol   Review        102
                   Energy in Building Life Cycle
                                               Minneapolis House             Atlanta House
                                               Wood            Steel      Wood        Concrete


                             Structure (GJ)     646            759         395             456
                          Maintenance (GJ)       73             73         110             110
                           Demolition (GJ)        7             7            7              9
         Embodied energy total (GJ)             727            840         512             573

75 years of heat &                                      7800                        4575
cooling energy (GJ)




LCA: General Definition   LCA Procedure   Paper Recycling   Housing    Bioethanol    Review      103
                Carbon Dynamics vs. Steady State

    • LCI provides a cross sectional profile of all
      processes -- a steady state analysis

    • Tracking carbon pools over time offers a
      dynamic alternative for a more financial
      cost/benefit perspective




LCA: General Definition   LCA Procedure   Paper Recycling   Housing   Bioethanol   Review   104
                                                    Net Product Life Carbon Emissions

                                           800
                                                                                          no
                                                                                        product
                                           600
                                                                                       carbon to
           CO2: Kg/cubic meter wood eq.




                                                                                         store
                                           400                                OSB

                                           200      KD
                                                  Lumber    Plywood
                                             0
                                                                                                Concrete
                                           -200                                                 floor area eq.

                                           -400

                                           -600                               includes carbon
                                                                              stored in product
                                           -800

                                          -1000




LCA: General Definition                             LCA Procedure   Paper Recycling   Housing      Bioethanol    Review   105
                                                       GWP Emissions for Framing Alternatives

                                            180%
                                                                                                      Concrete frame/wood frame
                                            160%                                                      Atlanta
 CO2 incr ease (%) fr om non- wood fr ame




                                            140%
                                                   Steel frame/wood frame
                                            120%   Minneapolis
                                            100%


                                            80%


                                            60%


                                            40%


                                            20%


                                             0%
                                                   Through                                                        ith
                                                                                                                W Product
                                                                   W
                                                                  1 ith Product                Through          2
                                                   Construction    Carbon                      Construction     Carbon



LCA: General Definition                                 LCA Procedure     Paper Recycling   Housing     Bioethanol   Review       106
                                                   Carbon In Forest Pools
                           450

                                                                                                    FIA data on old stands
                           400


                           350

                                                                        No harvest
 Metric Tons Per Hectare




                           300


                           250


                           200


                           150


                           100


                           50


                            0
                             2000   2010   2020   2030   2040   2050   2060   2070   2080    2090    2100   2110   2120   2130    2140    2150   2160
                                                                                      Year

Harvest rotation years                                                   45          80         120          NA



 LCA: General Definition                           LCA Procedure        Paper Recycling        Housing        Bioethanol         Review             107
                           Carbon Dynamics Need to be Considered

                                                                                                                     0-165 Years
                           400                       Averages over time intervals
                           350
                                                                                        0-120 Years
 Metric Tons per Hectare




                           300

                           250
                                                              0-80 Years
                           200

                           150
                                  0-45 Years
                           100

                            50

                            0
                                 45   80   120 NA            45   80    120 NA        45   80     120 NA         45     80    120 NA
                                                                       Rotation Length in Years


                                                    Forest    Products, Emissions, and Displacement    Sustitution


LCA: General Definition                        LCA Procedure       Paper Recycling     Housing      Bioethanol       Review            108
         Carbon Emissions in Representative
              Building Life Cycle Stages
                          CO2                       Minneapolis House                  Atlanta House
                     Metric Tons                    Wood          Steel          Wood             Concrete

   Emissions in Mfg                                  37.1         46.8            21.4             28.0
   Construction & Demo
   Emissions from Biofuel                             3.6          2.6             3.4              2.7
   Emissions from Maintenance                         3.4          3.4             4.1              4.1
   Emissions from Heating & Cooling                   390          390            232               232

   Subtotal of Sources                               434          443             261               267
   Forest Sequestration                              (467)        (246)           (103)             (85)

   Wood product Storage                             (22.4)       (11.8)          (17.1)            (14.1)

   Subtotal of Sinks and Stores                     (489)        (258)           (121)             (100)
   Net emissions                                     (55)         185             140               167
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               Interpretation: Environmental
                Improvement Opportunities
    • Redesign the house
          – use less fossil-intensive products (wood is good!)
          – reduce energy use (both active and passive)
          – improve durability to increase useful life
    • Improve the product
          –   greater use of biofuel
          –   engineered products for greater raw materials efficiency
          –   increase process efficiencies, especially in drying
          –   pollution control improvements
          –   increase product durability
    • Reduce, reuse and recycle demolition wastes




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              LCA Strengths & Weaknesses
    • Pro                                               • Con
          – System wide                                     – Dependent on
          – Quality and                                       quality of LCI
            objectivity                                     – LCI difficult to
          – Multiple impact                                   establish
            factors                                         – Steady state
                                                               – Resources
                                                                 change
                                                               – Time value of
                                                                 money
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                 Life Cycle Assessments
             Biomass to Ethanol from Different
                   Regional feedstocks




                                Jesse Daystar, Richard Venditti*
                          Based on work of Kemppainen and Shonnard
                            Department of Wood and Paper Science
                                 North Carolina State University
                                   Raleigh, NC 27695-8005
                                    *Corresponding author:
                          Richard_Venditti@ncsu.edu, (919) 515-6185

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                           Biomass to Ethanol


 • U.S. Department of Agriculture Biomass Estimation
       – Estimated 3.56 million dry tons on a sustainable basis in U.S.
         per day2
 • U.S. Oil Consumption
       – 868.6 million gallons/day1
 • Potential ethanol production
       – 9.58 million gallons per day of oil equivalents2

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                              Life Cycle Assessment
                           -applied to cellulosic ethanol

                          Goal and Scope
                            Definition




                     Inventory Analysis                        Interpretation




                    Impact Assessment




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                                            Goals
    • To compare the environmental impacts of two
      processes that utilize different regional
      cellulosic feedstocks to produce ethanol.
          1. Yellow Poplar regional to Michigan
          2. Recycled Newsprint




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                                           Scope
    • "Cradle to gate”
          – Acquisition of raw material through production of
            ethanol
    • Different from “cradle to grave”
          – Will not investigate the impacts of the use of ethanol
    • Why Cradle to Gate?
          – End use of ethanol for both alternatives is identical
       Cradle                                                             Production Gate




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                              Life Cycle Assessment
                           -applied to cellulosic ethanol

                          Goal and Scope
                            Definition




                     Inventory Analysis                        Interpretation




                    Impact Assessment




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                    Simulation and Modeling
                         Yellow Poplar
                          Pre-manufacturing

  diesel &                                                                     Raw material &
  gasoline                                                                     energy
                                   diesel
                                                  electricity
                                 Transportation
    Felling & Skidding                             Chipping                      Ethanol Production




             Boustead Model                                       ASPEN Simulation & EFRAT
             Emissions Factors &
             EFRAT

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                    Simulation and Modeling
                           News Print
                          Pre-manufacturing

  diesel &                                                                     Raw material &
  gasoline                                                                     energy
                                   diesel
                                                  electricity
                                 Transportation
   Collection & Sorting                             Pulping                      Ethanol Production




             Boustead Model                                       ASPEN Simulation & EFRAT
             Emissions Factors &
             EFRAT

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                      Feedstock Composition
                                                 % dry wt basis
                               Yellow
                            Poplar(NREL)        Yellow Poplar
           component               3        upper Michigan timber        newsprint
           cellulose            42.6                49.15                  63.77
           xylan                19.05               16.89                  5.26
           arabinan             0.79                 1.04                  0.61
           mannan               3.93                 3.76                  4.96
           galactan             0.24                 1.01                  0.61
           acetate              4.64                 3.38                  0.00
           lignin               27.68               24.45                  21.26
           ash                  1.00                 0.31                  3.54
           moisture             47.9                 68.4                   5.0




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                              Boustead Model
                                                                         Standard Data Sets




                     Custom Data Sets       Transportation
                                            distances, materials
                                            used, utilities




                                          Life Cycle Inventory Results




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                      NREL Process Modeling
        •Modeling software
           ASPEN
              •Developed by M.I.T. and the Department of Energy
              •Process modeling
              •Process optimization




                                          Life Cycle Inventory Results




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                            Pre-manufacturing
                              Energy Usage
                                 upper MI timber                               newsprint
                            Kg/h              MJ/h                         Kg/h        MJ/h
                 Premanufacturing, Chemicals
   ammonia                   1,194           88,620                        638         47,370
   ammonium sulfate           108             2,216                        169          3,376
   antifoam                   268            21,628                        356         28,696
   calcium phosphate          108             1,161                        169          1,899
   diesel                     470              557                          0             0
   gasoline                   938             1,088                        978          1,134
   lime                       693             8,124                        570          6,647
   sulfuric acid             1,839            9,495                       1,680         8,651
            subtotal                               132,889                             97,773

                   Premanufacturing, Operations
   felling (gasoline)            21             1,688                        0            0
   skidding (diesel)             33             2,216                        0            0
   transportation (diesel)      157             6,752                       232         9,917
   chipping (gasoline)           12              633                         0            0
   pulping (electricity)                               0                                9,073
            subtotal                               11,289                              18,990


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                       Simplified Process Flow
                               Ammonia, Lime, Acid


Feedstock        Feed              Chips                                 Sugars
                                                 Pretreatment
                Handling                                                                 Hydrolysis &
                                                (Detoxification)
                                                                                         Fermentation

    Recycle water
                                           Recycle Water
                                           Nutrients
                                           Air                                 Enzyme
       Waste Water                                                                                        Steam
         Treatment                                   Cellulase
     (Solid Separation)
                                            Excess Condensate
                                                                                       Product & Water
                                                                                          Recovery
                    Still Solids

                                                                                                    Ethanol
              Utilities                         Waste
                                              Combustion
                                                                                               Ethanol
                                                           Electricity                         Storage
                                           Steam
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                          Detailed Process Flow




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                        Energy Balance
                     Upper Michigan Timber




   •Process loses 9.7% of total energy through processes inefficiencies

   •30% of total energy consumed in cooling water system
       This is higher than newsprint due to higher boiler throughput

   •Energy balance has an accuracy of 2%


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                                Energy Balance
                                  News Print




   •2.2% more energy leaves with ethanol product for newsprint
   compared to timber process


   •Energy balance has an accuracy of 0.3%




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                          Process Air Emissions




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                                 LCA Progress So Far
                                                                           ☐
  •So far we have
                                    
      •Defined scope
      •Defined goal/objective
      •Performed inventory analysis
      •Performed energy balance     


  •Next
     •Impact assessment                            ☐
     •LCA interpretation
     •LCA improvement




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                              Life Cycle Assessment
                           -applied to cellulosic ethanol

                          Goal and Scope
                            Definition




                     Inventory Analysis                        Interpretation




                    Impact Assessment




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                                    Impact Modeling

     •Environmental Fate and Risk Assessment Tool (EFRAT)

     •Developed by Michigan Technological Institute
                 Department of Chemical Engineering

     •Model basis
           simulation output
           preprogrammed chemical and soil properties

     •Evaluates
           8 environmental indices
           Safety factors
           Economic factors

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                              Environmental Indices

            1. IGW – global warming
            2. ISF – smog formation
            3. IOD – ozone depletion
            4. IAR – acid rain
            5. IINH – human inhalation
            6. IING – ingestion toxicity
            7. ICINH -human carcinogenic inhalation
            8. ICING – carcinogenic ingestion toxicity
            9. IFT – fish toxicity




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                                               Environmental Indices
                                                    (Kg/L EtOH)
                                                                                     carcinogenic         Human
                                                                         Human                                          Global   Smog
                                  Fish Toxicity Ingestion Toxicity                     ingestion       Carcinogenic                             Acid Rain
                                                                       Inhalation                       Inhalation     Warming Formation
                                                                                        toxicity
                                        Upper Michigan Timber
   premfg process a               3.83E-06          1.52E-07           0.129         1.83E-11          6.1E-13          0.526 1.85E-05 3.59E-03
   mfg process                        2.32             26.1            0.415               0                0           -0.33 6.66E-04 3.46E-02
   total (kg/L EtOH)                  2.32          26.1               0.542         1.83E-11          6.1E-13          0.196 6.68E-04 2.82E-02
                                                  Newsprint
   premfg processb                3.20E-06          1.65E-07           0.119         2.42E-11 8.08E-13                  0.478 1.78E-05 3.36E-03
   mfg process                        1.02             26.9            0.433               0                0           0.291 5.44E-04 3.09E-02
   total (kg/L EtOH)                  1.02             26.9            0.552         2.42E-11 8.08E-13                  0.769 5.60E-04 3.43E-02
   a Impacts   from producing chemicals used in the ethanol process, for felling, skidding, and transportation of timber and of chipping.

   b   Impacts from producing chemicals used in the ethanol process, of transportation of newsprint, and of pulping




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                   Normalized Environmental Indices

            • Each environmental index is multiplied by a
              weighting factor

            • The sum of all weighted indices=
                  IL-CC – life cycle composite index

            • Life cycle composite index gives an overall
              value to process impacts




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          Normalized and Weighted Environmental Indices
                                                                                                       Higher
                          (Kg/L EtOH)                                                                 Weighting
                                                                                                       Factor

         Upper MI Timber                                             Newsprint
                          Weighted    Weighting                            Weighted       Weighting
(Kg/L)       Index         Index       Factor            Index              Index          Factor
ICINH     6.10E-13        1.45E-18        2.4E-06     8.08E-13         1.93E-18           2.4E-06
ICING     1.83E-11        4.33E-17        2.4E-06     2.42E-11         5.70E-17           2.4E-06
IFT          2.32         1.78E-08        7.7E-09        1.02          7.85E-09           7.7E-09
IING         26.1         1.01E-07        3.8E-09        26.9          1.04E-07           3.8E-09
IINH         0.542        2.09E-09        3.8E-09       0.552          2.13E-09           3.8E-09
IAR       3.83E-02        2.12E-11        5.5E-10     3.43E-02         1.91E-11           5.5E-10
ISF       6.68E-04        8.80E-14        1.3E-10     5.60E-04         7.40E-14           1.3E-10
IGW        0.196   8.93E-14 4.6E-13                    0.769           2.49E-13  4.6E-13
IL-CC    MI Timber 1.21E-07                          Newsprint           1.14E-7

         Newsprint process has about 6% lower life cycle composite index.
                                                                                                       Lower
                                                                                                      Weighting
                                                                                                       Factor
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                              Life Cycle Assessment
                           -applied to cellulosic ethanol

                          Goal and Scope
                            Definition




                     Inventory Analysis                        Interpretation




                    Impact Assessment




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        Life Cycle Improvement Analysis

      Process improvements to reduce emissions
      1. Cellulase seed reactor vent recycle stream

      2. Cellulase seed reactor vent stream as combustion air




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            Life Cycle Improvement Analysis
              Seed Reactor Recycle Stream
      • Recycle 75% of Cellulase seed reactor vent back to the Cellulase
        seed reactor
           Recycle stream already at operating pressure
           Recycle stream contains 90% of required O2 concentration

      Yellow Poplar
                            4.8% reduction of compressed air
                            7.5 % reduction in total utilities
                            2.2% reduction in IL-CC
      Newsprint
                            50% reduction in compressed air
                            8.6% reduction in utility consumption
                            6.4% increase in IL-CC



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                    Life Cycle Improvement Analysis
                    Seed Reactor vent stream recycle




  •Indices compared to original process

  •Yellow Poplar
       •All indices decreased
       •Less volatile organic compounds released

  •Newsprint
      •Increase in IFT, IING, and ISF
      •Decrease in IGW and IAR
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             Life Cycle Improvement Analysis
        Seed Reactor vent stream as combustion air
      • Volatile Organic Compounds (VOC) from the seed reactor are
        combusted and used for energy

      • Yellow Poplar
            0.4% utilities reduction
            20% decrease in ISF, and IING
            2.7% reduction in IL-CC
      • News Print
           2.1% utilities reduction
           20% decrease in ISF, and IING
           18.0% reduction in IL-CC




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             Life Cycle Improvement Analysis
        Seed Reactor vent stream as combustion air




 •Indices compared to original process

 •The smog formation indices decrease significantly as a result of utilizing the
 heating value of ethanol to offset natural gas usage

 •Reduction in the ingestion index also results from less ethanol in the vent stream




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                               Life Cycle Assessment
Newsprint
                                     Conclusions
   Pros
       1. Less fossil fuel required in pre-manufacturing
       2. Lower ecotoxicity
       3. Lower overall IL-CC

     Cons
            1. Manufacturing process is not energy self sufficient
            2. Higher index for IING, IINH, ICING, ICINH, and IGW

Yellow Poplar Timber
    Pros
        1. Manufacturing process is self sufficient and exports electricity to the grid
        2. Lower global warming index
        3. Lower impacts to human health
    Cons
        1. More fossil fuel required in pre-manufacturing
        2. Higher ecotoxicity
        3. Higher overall IL-CC


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                               Life Cycle Assessment
                                     Conclusions
Main chemical contributors to indices
    • acetic acid
    • Carbon monoxide
    • Ethanol


Fossil fuel energy required to produce transportation fuel
   • Yellow Poplar (ethanol)- 14% of energy content
   • Newsprint (ethanol)- 27% of energy content
   • Petroleum (gasoline/diesel)- 20% additional energy needed

Future Work

•    Impacts of large scale timber harvesting need to be examine

•    Additional studies comparing biomass-to-ethanol facilities to petroleum refineries
     needed to evaluate local health impacts1



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                                 LCA Overall Review

      •What you learned how to
        •Define the goals and scope of a LCA
        •Perform inventory analysis
        •Perform an impact assessment


      •Examples reviewed
         •Copy paper case study
         •Building material case study
         •Bioethanol case study




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                          Copy Paper Case Study Review

  • The Recycling scenario has the smallest carbon footprint

  • Landfill carbon footprint is highly dependent on the methane
    recovery rate

  • Increased recycling may reduce green house gas emissions

  • Increased recycling may impact the wood market
        – These impacts are outside the scope of the study




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                          Housing Case Study Review
  • Atlanta house
     • Wood-
         • 512 GJ embodied energy

        • Concrete-
           • 573 GJ embodied energy
           • 26% higher emissions
           • 120% higher emissions when including carbon sequestered

  • Minneapolis
     • Wood-
        • 727 GJ embodied energy

        • Steel frame-
           • 840 GJ embodied energy
           • 31% higher emissions
           • 156% higher emissions when including carbon sequestered

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                                 LCA Overall Review

      •LCA has a great potential to help decrease the impacts of
      industrial processes

      •LCAs can be a powerful marketing tool

      •LCA can be an effective means to quantify and minimize
      emissions

      •LCA may become increasingly important with the
      introduction of carbon credits




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                                     References
          1. Energy Information Administration, Petrolium basic statistics;
             http://www.eia.doe.gov/basics/quickoil.html

          2. Kelly, Stephen; Forest Biorefineries: Reality, Hype or
             Something in Between?; Paper Age, March 2006;

          3. Kemppainen, Amber; Shonnard, David; Comparative Life-
             Cycle Assessment for Biomass-to-Ethanol Production from
             Different Regional Feedstocks; Department of Chemical
             Engineering, Michigan Technological University; Biotechnol.
             Prog. 2005, 21, 1075-1084.

          4. Wooley, R.; Ruth, M.; Sheehan, J.; Ibsen, K.; Majdeski, H.;
             Galvez. A. Lignocellulosic Biomass to Ethanol Process
             Design and Economics Utilizing Co-Current Dilute Acid
             Prehydrolysis and Enzymatic Hydrolysis Current and Future
             Scenarios; National Renewable Energy Laboratory,
             NREL/TP-580-26157, July 1999

LCA: General Definition   LCA Procedure   Paper Recycling   Housing   Bioethanol   Review   148

								
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