A Cradle-to-Gate Life Cycle Assessment of Canadian Medium Density Fiberboard (MDF) Update. Final Report. Prepared for: Canadian Wood Council

Transcription

1 A Cradle-to-Gate Life Cycle Assessment of Canadian Medium Density Fiberboard (MDF) Update Final Report Prepared for: Canadian Wood Council By: Athena Sustainable Materials Institute Ottawa, ON This updated report is based on a 2009 Athena Institute report sponsored by FPInnovations September 2013

2 Disclaimer Although the ATHENA Sustainable Materials Institute has gone to great lengths to ensure the accuracy and reliability of the information in this report, this study is based on both proprietary and third-party (secondary) life cycle inventory (LCI) data sources provided by government agencies, research institutes, consultancies and other open and grey literatures, therefore the Institute does not warrant the accuracy thereof. If notified of any errors or omissions, the Institute will take reasonable steps to correct such errors or omissions. Athena Sustainable Materials Institute i

3 Glossary of Terms Based on ISO 14040/44:2006, ISO 21930:2007, ISO 14025:2006 and FPInnovations Wood PCR:2011. Allocation: Partitioning the input or output flows of a process or a product system between the product system under study and one or more other product systems. Cradle-to-gate: A cradle-to-gate assessment considers impacts starting with extracting raw materials from the earth (the cradle ) and ending at the plant exit gate where the product is to be shipped to the user. In-bound transportation of input fuels and materials to the plant is included. Out-bound transportation of the product to the user is not included. The use phase, maintenance and disposal phase of the product are also not included within the scope of this study. Disposal of on-site waste at the plant and outside, and transportation within the plant (if applicable) are included. Functional unit: Quantified performance of a product system for use as a reference unit. Declared unit -Quantity of a wood building product for use as a reference unit, e.g. mass (kilogram), volume (cubic metre), for the expression of environmental information needed in information modules. Note: The declared unit is used in instances where the function and the reference scenario for the whole life cycle of a wood building product cannot be stated (FPInnovations Wood PCR:2011- adapted from ISO 21930:2007). Life Cycle: Consecutive and interlinked stages of a product system, from raw material acquisition or generation from natural resources to final disposal. Life Cycle Assessment (LCA): Compilation and evaluation of the inputs, outputs and the potential environmental impacts of a product system throughout its life cycle. Life Cycle Impact Assessment (LCIA): Phase of life cycle assessment aimed at understanding and evaluating the magnitude and significance of the potential environmental impacts for a product system throughout the life cycle of the product. Life Cycle Interpretation: Phase of life cycle assessment in which the findings of either the inventory analysis or the impact assessment, or both, are evaluated in relation to the defined goal and scope in order to reach conclusions and recommendations. Athena Sustainable Materials Institute ii

4 Product Category Rules (PCR): Set of specific rules, requirements and guidelines for developing Type III environmental declarations for one or more product categories. Product system: Collection of unit processes with elementary and product flows, performing one or more defined functions, and which models the life cycle of a product. Reference flow: Measure of the outputs from processes in a given product system required to fulfill the function expressed by the functional unit. System boundary: Set of criteria specifying which unit processes are part of a product system. Note: the term system boundary is not used in this International Standard in relation to LCIA. Type III environmental declaration/environmental product declaration (EPD) Environmental declaration that provides quantified environmental data of a product, using predetermined parameters and, where relevant, additional environmental information (adapted from ISO 14025). Athena Sustainable Materials Institute iii

5 Contents GLOSSARY OF TERMS... II LIST OF FIGURES... V LIST OF TABLES... VI ACRONYMS AND ABBREVIATIONS... VII 1 INTRODUCTION LIFE CYCLE ASSESSMENT ACCORDING TO ISO SERIES GOAL AND SCOPE DEFINITION LIFE CYCLE INVENTORY LIFE CYCLE IMPACT ASSESSMENT INTERPRETATION STUDY GOALS AND SCOPE GOALS OF THE STUDY The reasons for carrying out the study Intended Uses Intended audience Comparative assertions SYSTEM BOUNDARIES Geographical distribution of participating MDF mills MDF Production System Boundaries Functional and Declared Unit Cut-off Criteria Allocation Methods Impact Categories / Impact Assessment Biogenic Carbon Treatment DATA SOURCES AND AVERAGING PRIMARY AND SECONDARY DATA SOURCES METHODOLOGY FOR AVERAGING DATA LIFE CYCLE INVENTORY UPSTREAM WOOD RESIDUES PROCESSING RESOURCE AND MATERIAL TRANSPORTATION MDF MANUFACTURING Mass Balance Gate-to-Gate LCI of MDF manufacturing production system LIFE CYCLE IMPACT ASSESSMENT, USE OF RESOURCES AND GENERATION OF WASTE LIFE CYCLE INTERPRETATION IDENTIFICATION OF THE SIGNIFICANT ISSUES Unit processes Contribution Analysis Substance Contribution Analysis COMPLETENESS, CONSISTENCY AND SENSITIVITY CHECKS CONCLUSIONS, LIMITATIONS AND RECOMMENDATIONS REFERENCES APPENDIX A- SUBSTANCE CONTRIBUTION ANALYSIS Athena Sustainable Materials Institute iv

6 List of Figures Figure 1: Life Cycle Assessment methodology: the ISO framework and applications... 3 Figure 2: Geographical distribution of participating Canadian MDF mills... 7 Figure 3: MDF Manufacturing Process... 9 Figure 4: Depiction of horizontal approach for averaging the Canadian MDF LCI Data Figure 5: Sensitivity Analysis Results Mass vs. Economic Allocation Athena Sustainable Materials Institute v

7 List of Tables Table 1: MDF Process Description Table 2: Selected Impact Indicators Table 3: Secondary LCI Data Sources Table 4: Summary of Raw Material Transportation by Mode and Distance to MDF mills Table 5: Wood Mass balance for Canadian MDF Manufacture per m3 and MSF basis Table 6: Gate-to-gate weighted average LCI flows of Canadian MDF manufacturing system (based on data provided by 4 Canadian MDF mills for 2006 calender year) Table 7: LCIA Results Summary for Cradle-to-Gate production of 1 m 3 of MDF absolute basis (mass allocation, unit process approach) Table 8: LCIA Results Summary for Cradle-to-Gate production of 1 m 3 of MDF percentage basis (mass allocation, unit process approach) Table 9: LCI Parameters Required by Wood PCR absolute basis (mass allocation, unit process approach) Table 10: LCI Elements Required by Wood PCR percentage basis (mass allocation, unit process approach) Table 11: Unit Process Contribution Analysis for Manufacturing (S3) of 1 m3 of MDF absolute basis (mass allocation, unit process approach) Table 12: Unit Process Contribution Analysis for (S3) of 1 m3 of MDF percentage basis (mass allocation, unit process approach) Table 13: Substance Contribution Analysis to Global Warming Potential by Life Stage - % basis displays relative values vertically (within processes)- for MDF Table 14: LCIA Results Summary for Cradle-to-Gate production of 1 m3 of MDF absolute basis (economic allocation, unit process approach) Athena Sustainable Materials Institute vi

8 Acronyms and Abbreviations CED Cumulative Energy Demand CF Characterization Factor CFCs Chlorofluorocarbons CFC-11 Trichlorofluoromethane EPDs Environmental Product Declarations GWP Global Warming Potential H+ Hydrogen ion IC Impact Categories IPCC International Panel on Climate Change ISO International Organization for Standardization LCA Life Cycle Assessment LCI Life Cycle Inventory LCIA Life Cycle Impact Assessment LEED Leadership in Energy & Environmental Design MDF Medium Density Fiberboard MJ Megajoule N Nitrogen NO x Nitrogen Oxides O 3 Ozone P Phosphorous POCP Photochemical Ozone Creation Potential SETAC The Society of Environmental Toxicology and Chemistry SO 2 Sulfur dioxide TRACI Tool for the Reduction and Assessment of Chemical and Other Environmental Impacts UNEP United Nations Environment Program US EPA United States Environmental Protection Agency VOCs Volatile Organic Compounds Athena Sustainable Materials Institute vii

9 1 Introduction Over the past two decades, environmental issues have become an increasing priority for both government and private industry alike. Here in North America the emphasis has gradually broadened from site-specific environmental degradation to include the characterization of product burdens. Similarly, many private companies and/or their respective trade associations have increasingly emphasized environmental information and often share this information with their customers in the form of a environmental product declaration (EPD). Life cycle assessment (LCA), and especially its most developed component, life cycle inventory (LCI), is a tool that provides quantitative and scientific analyses of the environmental impacts of products and production systems. LCA is also the backbone on which a Type III EPD is based. The use of LCA is growing in the mainstream as green building ratings systems (e.g., LEED and Green Globes), other government procurement policies, and pollution prevention programs are contemplating or already incorporating the use of environmental performance measures that can only be objectively provided through a thorough LCA study. Similarly, many product manufacturing companies are adopting design for the environment environmental management systems to either reduce the overall mass or material complexity of their products or to streamline their manufacturing processes and consequently reduce environmental burdens emanating from their plants, as well as making it easier for their products to be recycled at their end-of-life. The Canadian Wood Council commissioned the Athena Institute to update the Institute s 2009 cradle-to-gate LCA of Canadian Medium Density Fiberboard (MDF) in support of a joint N. American environmental product declaration (EPD) initiative. Consequently, the original 2009 report has been revised in accordance with the new FPInnovations Wood PCR and to better align the Canadian LCA methodology with that of the CORRIM LCA undertaking for US wood products to achieve a more consistent N. American results outcome. The major changes captured in this updated report include: a) The declared unit 2 is defined in accordance with the FPInnovations Wood PCR 2011 [1] and ISO 21930: as one cubic meter of MDF product with mm (3/4- inch basis) 4 thickness and an equivalent surface of 52.5 m2 (565 square feet); b) In accordance with FPInnovations Wood PCR 2011, allocation within multi-output processes is applied on a mass basis; c) The life cycle impact assessment is completed using the US EPA s TRACI methodology; and d) The specific life cycle inventory (LCI) elements required by the PCR are reported. 1 FPInnovations (2011) Product Category Rules: North American Structural and Architectural Wood Products. November 2011, version 1 2 Refer to Glossary of Terms for the definition of the declared unit. 3 ISO 21930:2007: Sustainability in building construction - Environmental declaration of building products sq. ft (3/4-inch basis) is equal to m3 MDF product. Athena Sustainable Materials Institute 1

10 2 Life Cycle Assessment according to ISO series Life Cycle Assessment (LCA) is an analytical tool used to comprehensively quantify and interpret the environmental flows to and from the environment over the entire life cycle of a product or service. This includes emissions to air, water and land as well as the consumption of energy and other material resources. These studies involve the collection, validation, verification, assessment and interpretation of environmental data over a product s lifecycle (raw material acquisition, manufacture, transportation, use, maintenance and end-of-life). Studies can evaluate entire product life cycles, referred to as cradle-to-grave or cradle-to-cradle studies, or focus on parts of a product life cycle, referred to as cradle-to-gate or gate-to-gate studies. This study can be categorized as a cradle-to-gate assessment as it follows the production of MDF from the forest through to MDF manufacturing with a product ready for shipment at the plant gate. The ISO series is the international standard for Life Cycle Assessment [3], [4]. It was developed with international experts on LCA from more than fifty countries over a period of more than 15 years. The standard provides guidelines for performing LCA studies, establishing a consensus approach, while still allowing flexibility. Individual analysts may still interpret or modify the approach as required to deal with specific issues or concerns. The focus of the standard is on preventing misuse of LCA, particularly for studies that make comparative assertions about one product versus a competitor s product. Comparative assertions are not a goal of this study. There are several documents in the ISO series, covering the methodological steps for LCA and providing illustrations with examples 5. ISO sets out a four phase methodology framework for completing a LCA, as shown in Figure 1 below: (1) Goal and Scope Definition, (2) Life Cycle Inventory, (3) Life Cycle Impact Assessment, and (4) Interpretation. 5 ISO 14040:2006 Environmental Management Life Cycle Assessment Principles and Framework. ISO 14044:2006 Environmental Management Life Cycle Assessment Requirements and Guidelines. Athena Sustainable Materials Institute 2

11 Figure 1: Life Cycle Assessment methodology: the ISO framework and applications 2.1 Goal and Scope Definition An LCA starts with an explicit statement of the goal and scope of the study, the functional unit, the system boundaries, the assumptions and limitations, the allocation methods used, and the impact categories chosen. The goal and scope includes a definition of the context of the study, which explains how and to whom the results are to be communicated. The ISO standards require that the goal and scope of an LCA be clearly defined and consistent with the intended application. A functional unit is defined in ISO 14040:2006 as the quantified performance of a product system for use as a reference unit. The system boundaries establish what will be considered within the study and what will be excluded. Central to this is the functional unit of a study, which explicitly defines the service or function provided by the product system. The goal and scope definition step also defines the data and information that will be collected, and how the data will be assessed for quality, consistency, and environmental impact. This report sets out the specific goal and scope elements relevant to the LCA of the product and its system boundary. 2.2 Life Cycle Inventory Completing a life cycle inventory (LCI) involves compiling an inventory of relevant inputs and outputs of a product system, comprising mass and energy flows that contribute to various environmental issues and loadings. The inventory is carried out for each process step defined in the system. Depending on the goal and scope definition, data may be collected first-hand (primary data) from measurements and estimates of key activities, or it may be based on Athena Sustainable Materials Institute 3

12 information drawn from existing LCI databases (secondary data). Different levels of aggregation are possible, including individual processes and sub-systems (such as energy supply or transport, etc.). Typically, the inventory is collected using questionnaires and modelled using one of many LCA software packages. The Athena Institute used Sima Pro LCA Software to complete the LCI modelling of four MDF production facilities located in various regions of the country. Primary LCI data was collected from the four MDF facilities and their suppliers. All other data were from secondary sources (e.g., previously developed Institute LCI data or existing common fuels databases available in Sima Pro or other sources). The sources for all secondary data used in the study are presented in Table Life Cycle Impact Assessment This step assesses the potential environmental impacts associated with the measured environmental inputs and outputs compiled in the inventory. It is important to note here that LCA is not a single-issue tool; rather, the analysis encompasses numerous possible environmental burdens (e.g. primary energy use, climate change, acidification, smog etc.), thus allowing for broad consideration of the potential impacts of a process or product system and possible trade-offs across the selected issues. The life cycle impact assessment results are relative expressions and do not predict impacts on category endpoints such as human health or ecosystem quality, the exceeding of thresholds, safety margins, or risks. The Institute employed the US Environmental Protection Agency s (EPA) impact assessment method called TRACI (Tool for the Reduction and Assessment of Chemical and other environmental Impacts) 6 and applied it to the LCI data compiled for Canadian MDF manufacturing systems (see sections 3 and 4). The actual impact indicators employed are described more fully in section Interpretation As defined in ISO 14040: 2006, life cycle interpretation is a phase of life cycle assessment in which the findings of either the inventory analysis or the impact assessment, or both, are evaluated in relation to the defined goal and scope in order to reach conclusions and recommendations. This final step in an LCA involves an investigation of significant environmental aspects (e.g. energy use, greenhouse gases), their contributions to the indicators under consideration, and determination of which unit processes in the system they emanate from. For example, if the results of a life cycle impact assessment indicate a particularly high value for the global warming potential indicator, the analyst could refer back to the inventory to determine which environmental flows are contributing to the high value, and which unit processes those outputs are coming from. This is also used as a form of quality control, and the results can be used to refine the scope definition to focus on the more important unit processes. This step also supports arriving at more certain conclusions and supportable recommendations. 6 TRACI characterization factors used in this study were developed on a US average basis in 2011 (TRACI v2). Athena Sustainable Materials Institute 4

13 3 Study Goals and Scope 3.1 Goals of the study The reasons for carrying out the study The primary goal of this study is to update the previous 2009 Institute LCA study of Canadian MDF in accordance with the FPInnovations Wood PCR 2011 and thus provide a Canadian cradle-to-gate environmental profile of one cubic meter of MDF Intended Uses Specifically, the cradle-to-gate LCI and LCIA profile for MDF can be utilized in the following applications: Process Improvements and New Technology Evaluation The completed LCA can be used internally by either individual mills or by the Canadian Wood Council to evaluate possible process and parameter improvements and new technologies; Market Support The LCA will provide a detailed product profile, with key indicators of environmental performance for the complete manufacturing process. The LCA will be used to support the development of a Type III environmental product declaration (EPD). The product profile can also be used in other education and marketing efforts with environmentally conscious customers or organizations (e.g., LEED and Green Globes rating systems, government procurement programs, etc.); ISO The completed study may be used by MDF mills in the future to benchmark and track significant aspects and impacts over time within an ISO compliant environmental management program; Sustainable Development (SD) Reporting and Indicators Data from the LCA can be used for SD reporting. For instance, the individual MDF manufacturers may wish to voluntarily pursue a carbon footprint reporting method and indicator. This study can serve as a baseline from which such a program can be devised and monitored in the future; Design for the Environment the resulting line-by-line LCI in combination with the LCIA results for MDF can be used to identify environmental hotspots and related opportunities to improve production line processes and lessen the life cycle environmental impact of Canadian MDF Intended audience The primary audience for the LCA report is Canadian Wood Council and Canadian MDF mills. The Canadian Wood Council may make the study results available externally to North American suppliers, architectural, engineering, and specifying professionals, LCA practitioners and tool developers, academia, governmental organizations, policy makers and other interested parties who require reliable information on wood building products and processes. Athena Sustainable Materials Institute 5

14 3.1.4 Comparative assertions This LCA does not include comparative assertions. However, it may lead to future comparative studies intended to be disclosed to the public. As a result, an internal critical review was convened to ensure that the completion of this LCA study is consistent with the ISO 14040/44:2006 guidelines and principles and in compliance with the FPInnovations Wood PCR Furthermore, an independent critical review process by an external expert was conducted in conformity with Clause 6.2, ISO 14044:2006 to verify whether this LCA has met the requirements for methodology, data, interpretation and reporting and whether it is consistent with the ISO 14040/44:2006 principles. Thomas P. Gloria, Ph.D., LCACP, Managing Director, Industrial Ecology Consultants Lecturer, Harvard University Extension School, conducted the critical review of the MDF LCA study. The full review statement and the response to reviewer s recommendation can be provided upon the request. 3.2 System Boundaries Geographical distribution of participating MDF mills The MDF plants are dispersed across the country and each of the participating mills was located in a different province of the country British Columbia, Alberta, Ontario and New Brunswick. The size of MDF participating production facilities ranged from about 74 to 168 million square feet (3/4- inch basis) annually. The average age of the participating MDF mills was approximately 17 years. In 2006, the surveyed MDF mills operated 333 days with 2 production shifts per day on average. Three out of four MDF mills operated one production line while one MDF mill operatated two production lines. Seven MDF plants were operating in Canada in 2006, but many of these plants had closed their doors by the time of this study and report. Athena Sustainable Materials Institute 6

15 Figure 2: Geographical distribution of participating Canadian MDF mills Athena Sustainable Materials Institute 7

16 3.2.2 MDF Production System Boundaries The U.S Composite Panel Association defines medium density fiberboard (MDF) as a dryformed panel product manufactured from lignocellulosic fibers combined with a synthetic resin or other suitable binder. The panels are compressed to a density of from 496 to 801 kg/m3 (31to 50 lb/ft3) in a hot press. In contrast to particleboard, MDF has more uniform density throughout the board and has smooth, tight edges that can be machined 7. This study is a cradle-to-gate LCA study. It covers all of the production steps from upstream wood residue processing to finished products ready for shipment at the mill (i.e. the gate). It does not include the mill gate to building site transportation, product use or its endof-life disposition. This study draws on both primary mill data collected from the four mill operations, their suppliers, as well as secondary LCI data. For wood-based product LCAs, the infrastructures of the production facilities are usually not taken into account as these effects are negligible to the overall environmental impacts of the product over its life cycle [17]. The system boundaries include three main system processes in the production of MDF: upstream wood residue processing, wood residue and ancillary material transportation from suppliers to the mill and the MDF manufacturing process. The general manufacturing steps used to produce MDF include mechanical pulping of wood chips to fibers (refining), drying, blending of fibers with an adhesive (typically urea formaldehyde (UF) resin ( % solids by weight)) and wax, forming the resinated material into a mat, and hot pressing. One mill also reported a small amount methylurea formaldehyde (MUF) resin. Waxes (57-58% solids by weight) are usually added to impart water resistance. Catalysts (NH4Cl 8, NH4SO4) are usually used to accelerate the resin cure and to reduce the press time. Scavengers (between 50-59% solids by weight) also are added in the blending step to reduce fugitive formaldehyde emissions from the process. Table 1 below provides a description of the MDF production process. Figure 3 depicts each of the system processes included in the MDF manufacturing process gate-to-gate system boundry. For this study, the manufacturing process was further divided into four sub-unit processes (SU): SU1 Wood preparation including debarking & chipping (if applicable), screening, cooking bin & refining and blowline operation SU2 Drying- raw furnish drying SU3 Board shaping- panel forming and pressing SU4 Board finishing- cooling, trimming, sanding & packaging of the final panel. 7 RTI International 2003: Emission Factor Documentation for AP-42, Chapter Medium Density Fiberboard Manufacturing, Final Background Report, Prepared for U. S. Environmental Protection Agency; 8 Most Canadian mills use inorganic salts in the form of ammonium chloride (NH4Cl) for catalyst although there is some ammonium sulfate (NH4SO4) also used. Athena Sustainable Materials Institute 8

17 Figure 3: MDF Manufacturing Process The enviromental load of boilers and air emission control equipment was allocated by the mills to the respective sub-unit processes. Three out of four MDF mills did report an air make-up unit process. Where applicable, make-up air was allocated to the board finishing sub-unit process. Canadian MDF mills typically use a combination of air emission control devices - multicyclones (4 mills), bag house (4 mills), dust collectors (3 mills) and ESPelectrostatic precipitator (3 mills). Canadian MDF mills typically have a blowline system installed, where the wood fibers are first blended with resin, wax, and other additives in a blowline, which then discharges the resinated fibers to the dryer. While a separate blending process is sometimes used in MDF production none of the surveyed mills reported using a separate blending operation. Tube- dryers are commonly used in the MDF manufacturing process. Heat is usually provided to tube dryers by the direct firing of natural gas, hogfuel, diesel fuel (very limited) or by indirect heating. All Canadian MDF mills reported using both a pre-press and press system in their production lines. The press is heated by a thermal oil loop, the thermal oil is indirectly heated by the combustion of natural gas, hog fuel or diesel. Athena Sustainable Materials Institute 9

18 The raw wood furnish input for the Canadian MDF mills consisted of shavings, sawdust, chips and on-site generated sanderdust and panel trimmings 9. None of the four mills reported using raw logs as an input material. Wood residues typically are delivered by truck from off-site locations such as sawmills. Canadian MDF mills do not sell their by-products of production, but instead utilize these byproducts as hog fuel to fire mill boilers or as raw panel furnish to be reintroduced at the blowline. A very small amount of the incoming wood residues fibre (1%) ends up as wood waste (see Section 5.3). The study system boundary includes the transportation of major inputs to (and within) each production process, but it does not include transportation of final products to customers or any other downstream effects. Purchased electricity and any onsite generated energy is included in the system boundary. The extraction, processing and delivery of purchased primary fuels (e.g. natural gas and primary fuels used to generate purchased electricity are also included within the boundary). Liquid propane gas (LPG), gasoline, diesel fuel are typically used to run on-site mobile equipment. Natural gas and hogfuel (generated in-house and purchased) typically are used for thermal heat generation purposes. One MDF mill reported using diesel fuel for the purpose of heat generation. For purposes of this LCA study, life cycle inventory data for the 2007 calendar year were collected for the production of the UF resin and scavenger (a by-product) in Canada. The significant ancillary materials (e.g., wax, catalyst, scavenger, hydraulic fluids, motor oils and greases ) were also included within the system boundary (see below for cut-off criteria). 9 One mill did report a minimal amount (less than 0.1%) of municipal solid waste use in the MDF production. Athena Sustainable Materials Institute 10

19 Table 1: MDF Process Description No. System/Unit Description Processes I Wood residues production The surveyed MDF mills typically use wood residues (shavings, sawdust, chips, sanderdust and panel trim) as the raw resource for MDF manufacturing. The environmental burden of the upstream wood residues processing, which are typically by-products of lumber industry, is included in this LCA study. II III Wood Residues and Material Transportation The Wood residues and material transportation system process includes the transportation of the wood residues, urea formaldehyde resin, wax, scavenger, catalyst, lubricants, various oils and greases to the mill by mode (e.g., truck, water or rail). MDF Manufacturing Process SU1 Debarking & Chipping Not reported by the surveyed mills. Screening Oversized or undersized particles are screened out. Overs are typically be reprocessed. Some undersized particles may be transferred to heat generation process. Cooking bin & Refining The raw furnish is compacted using a screwfeeder, and then heated for seconds to soften the wood before being fed into a defibrator at high pressure and temperature. The pulp that exits from the defibrator is fine, fluffy, and light in weight and colour. Blowline From the defibrator the pulp enters the blow line where it is SU2 Drying blended with resin, catalyst, wax and scavenger and then enters the pre-dryer and finally the main dryer. SU3 Forming When it comes out of the dryer it may be stored in bins for a short period prior to being fed into the forming line creating a layered fibre mat. SU4 Pressing The MDF mat continues to the press. Here it is pressed for a few minutes, to make a strong and dense board. Cooling After pressing the MDF is cooled in a star type cooling wheel; Trimming Sanding & Packaging Heat generation Air Emissions Control After cooling the MDF is trimmed; trim is typically sent to heat generation After trimming the MDF is sanded and then sent to packaging areas. Sander dust may also be sent to heat generation encompasses fuel storage, conveyance, boiler/fuel cell/oil heater, turbines and steam distribution system (if applicable). is devoted to air pollution control including multicyclone, bag house, dustcollector, electrostatic precipitator (ESP) etc. Athena Sustainable Materials Institute 11

20 Both human activity and capital equipment were excluded from the system boundary. The environmental effects of manufacturing and installing capital equipment and buildings have generally been shown to be minor relative to the throughput of materials and components over the useful lives of the buildings and equipment. Human activity involved in the manufacturing of MDF no doubt has a burden on the environment. However, the data collection required to properly quantify human involvement is particularly complicated, and allocating such flows to the production of materials as opposed to other societal activities was not feasible for a study of this nature. Typically, human activity is only considered within the system boundary when value-added judgements or substituting capital for labour decisions are considered to be within the scope of the study. These types of decisions are outside the current goal and scope of this study Functional and Declared Unit The purpose of the functional unit is to quantify the service delivered by the product system and provide a reference to which the inputs and outputs can be related. For EPDs covering the complete life cycle (based on a cradle-to grave LCA study), a functional unit is defined. For EPDs not covering the complete life cycle (e.g. cradle-to gate LCA study -leaving out the use stage and/or the end of life stage), a declared unit is defined. As specified in FPInnovations Wood PCR 2011, Section 7 and ISO 21930:2007, the functional unit or declared unit of a product provides the quantitative normalization for comparing building products of equivalent function or equivalent specification. The declared unit is defined as the production of one cubic meter (1 m 3 ) of MDF product with a mm thickness (3/4-inch basis) and an equivalent surface of 52.5 m2 (565 square feet) Cut-off Criteria ISO 14040: 2006 defines the cut-off criteria, as a specification of the amount of material or energy flow or the level of environmental significance associated with unit processes or product system to be excluded from a study. The cut-off criteria for input flows to be considered within the system boundary were defined as follows: a. Mass if a flow is less than 1% of the cumulative mass of the model flows it may be excluded, providing its environmental relevance is minor. b. Energy if a flow is less than 1% of the cumulative energy of the system model it may be excluded, providing its environmental relevance is minor. c. Environmental relevance if a flow meets the above two criteria, but is determined (via secondary data analysis) to contribute 2% or more to any product life cycle impact category (see below), it is included within the system boundary. Waste treatment of manufacturing waste falls below the cut-off criteria and was thus excluded from the study. Athena Sustainable Materials Institute 12

21 3.2.5 Allocation Methods Allocation is the method used to partition the environmental load of a process when several products or functions share the same process. In accordance with FPInnovations Wood PCR 2011, Section 8.3. Allocation rules, mass was deemed as the most appropriate physical parameter for allocation. The weighted average raw wood residues input consisted of 42% shavings, 35% sawdust, 21% chips and 2% internal sanderdust and panel trim. The environmental profile of wood residue inputs to the MDF plant (shavings, sawdust, chips, etc.) is based on other recent Institute studies. These data include a Canadian weighted average profile (based on mass allocation rules and methods) for shavings, sawdust and chips (by-products of lumber production system). Sanderdust and panel trim are byproducts of the MDF process itself (closed-loop recycling) Impact Categories / Impact Assessment As defined in ISO 14040:2006, the impact assessment phase of an LCA is aimed at evaluating the significance of potential impacts using the results of the LCI analysis. In the life cycle impact assessment (LCIA) phase, we model a set of selected environmental issues referred to as impact categories, and use category indicators to aggregate similar resource usage and emissions to explain and summarize LCI results data. These category indicators are intended to characterize the relevant environmental flows for each environmental issue category in order to represent the potential or possible environmental impacts of a product system. According to LCA-based ISO 14040/44:2006 [3, 4], the mandatory elements of LCIA are: 1. Selection of impact categories, category indicators and models. 2. Assignment of the LCI results to the impact categories (classification) the identification of individual inventory flow results contributing to each impact indicator selected. 3. Calculation of category indicator results (characterization) the actual calculation of the potential or possible impact of a set of inventory flows identified in the previous classification step. The impact categories and assessment methods are the mid-point indicators from the U.S. EPA Tool for the Reduction and Assessment of Chemical and Other Environmental Impacts - TRACI 2, 2011 [5]. The TRACI methodologies were developed specifically for the US using input parameters consistent with US locations and are consistent with ISO 21930:2007, Sustainability in building construction Environmental declaration of building products category indicators and the wood product PCR. They include global warming, ozone depletion, photochemical oxidants (smog), eutrophication, and acidification potential. Further, total primary energy consumption is tabulated from the life cycle inventory results and reported on a segregated basis as non-renewable fossil, non-renewable nuclear, renewable (solar, wind, hydroelectric and geothermal) and renewable biomass. Higher Athena Sustainable Materials Institute 13

22 heating value (HHV) of primary energy carriers is used to calculate the primary energy values reported in the study. In accordance with FPInnovations Wood PCR 2011, Section 9.1, Table 3, the following TRACI impact categories (IC) and characterization factors (CF) 10 were selected and reported (also see Table 3). Global warming (IC) - TRACI uses global warming potentials (CF), a midpoint metric proposed by the International Panel on Climate Change (IPCC), for the calculation of the potency of greenhouse gases relative to CO2. The 100-year time horizons recommended by the IPCC and used by the United States for policy making and reporting are adopted within TRACI. Within TRACI 2.0, the most current GWPs published by IPCC (2007) were used for each substance. Global warming potential (GWP) the methodology and science behind the GWP calculation can be considered one of the most accepted LCIA categories. GWP 100 is expressed on equivalency basis relative to CO 2 i.e., equivalent CO 2 mass basis. Acidification (IC) - As per TRACI, acidification comprises processes that increase the acidity (hydrogen ion concentration, [H+]) of water and soil systems. Acidification is a more regional rather than global impact effecting fresh water and forests as well as human health when high concentrations of SO 2 are attained. The Acidification potential (CF) of an air emission is calculated on the basis of the number of H+ ions which can be produced and therefore is expressed as potential moles H+ molar equivalents per kg of contributing emission. Eutrophication (IC) - In TRACI, eutrophication is defined as the fertilization of surface waters by nutrients that were previously scarce. This measure encompasses the release of mineral salts and their nutrient enrichment effects on waters typically made up of phosphorous and nitrogen compounds and organic matter flowing into waterways. The result is expressed on an equivalent mass of nitrogen (N) basis. The characterization factors estimate the eutrophication potential of a release of chemicals containing N or P to air or water, per kilogram of chemical released, relative to 1 kg N discharged directly to surface freshwater. Photochemical smog (IC) - Photochemical ozone formation potential (CF) Under certain climatic conditions, air emissions from industry and transportation can be trapped at ground level where, in the presence of sunlight, they produce photochemical smog, a symptom of photochemical ozone creation potential (POCP). While ozone is not emitted directly, it is a product of interactions of volatile organic compounds (VOCs) and nitrogen oxides (NO x ). The smog indicator is expressed on a mass of equivalent ozone (O 3 ) basis. Ozone depletion (IC) - Stratospheric ozone depletion is the reduction of the protective ozone within the stratosphere caused by emissions of ozone-depleting substances. International consensus exists on the use of Ozone Depletion Potentials (CF), a metric proposed by the World Meteorological Organization for calculating the relative importance of CFCs, 10 Characterization factor is a factor derived from a characterization model which is applied to convert an assigned life cycle inventory analysis result to the common unit of the category indicator. The common unit allows calculation of the category indicator result [ISO 14040:2006]. Athena Sustainable Materials Institute 14

23 hydrochlorofluorocarbons (HFCs), and halons expected to contribute significantly to the breakdown of the ozone layer. Within TRACI 2.0, the most recent sources of ODPs (WMO 2003) were used for each substance, where chemicals are characterized relative to trichlorofluoromethane (CFC-11). Total primary energy (IC) Total primary energy is the sum of all energy sources which are drawn directly from the earth, such as natural gas, oil, coal, biomass or hydropower energy. The total primary energy contains further categories namely non-renewable and renewable energy, and fuel and feedstock energy. Non-renewable energy includes all fossil and mineral primary energy sources, such as natural gas, oil, coal and nuclear energy. Renewable energy includes all other primary energy sources, such as solar, wind, hydroelectric and geothermal and biomass. Feedstock energy (both non-renewable, fossil and renewable) is that part of the primary energy entering the system which is not consumed and/or is available as fuel energy and for use outside the system boundary. The feedstock energy was calculated based on an assumed HHV of 20 MJ/kg to align with the PCR reporting recomendation 11. Total Primary Energy is expressed in MJ. Table 2: Selected Impact Indicators Impact category Unit Source method Level of site specifity Environmental media Air TRACI 2.0/ Global warming kg CO2 eq IPCC 2007 Global Acidification mol H+ eq TRACI 2.0 North America Air Eutrophication kg N eq TRACI 2.0 North America Air, Water Smog kg O3 eq TRACI 2.0 North America Air Ozone depletion Total primary energy consumption* Non renewable, fossil Non-renewable, nuclear Renewable, biomass Renewable (solar, wind, hydroelectric and geothermal) kg CFC-11 eq MJ TRACI 2.0/WMO:2003 CED Adapted (last SP update Aug 2010) Global Global Air Natural resources 20 MJ/kg manual Feedstock, renewable calculation [6],[15] * Non renewable, fossil (combusted and feedstock), Non renewable, nuclear, and Renewables (biomass and solar, wind, hydroelectric and geothermal) are subsets of Total primary energy consumption Furthermore, in accordance with FPInnovations Wood PCR 2011, Section 9.1, Table 3, material resource consumption (in kg) and waste generated (in kg) are also reported broken into consumption of non-renewable materials, renewable materials, fresh water and waste generated - see section FPInnovations PCR (2011): Section 9.1, pg 11, Notes for Table 3, item 4 The heating value of the wood building product itself (feedstock energy, renewable) should be reported separately from other renewable primary energy on a higher heating value (HHV) basis. Athena Sustainable Materials Institute 15

24 3.2.7 Biogenic Carbon Treatment FPInnovations Wood PCR 2011 adopts the biogenic carbon accounting practice that is widely employed in LCA practice and is specified by the Norwegian Solid wood product PCR 12 as follows: CO2 emissions due to the combustion of wood fuels are considered equal to the CO2 uptake in the forestry growth (neutral CO2 balance). For this reason, the inventory which the EPD is based on will not include emissions/uptake of CO2 in relation to wood fuels." It follows that the biogenic carbon emissions are not considered as contributing to the global warming potential impact category. While biogenic carbon emissions are accounted as carbon neutral, the carbon sequestered in the MDF product can only be considered as an uncertain carbon credit because the eventual fate of that carbon is unknown in cradle-to-gate LCA such as this one. The FPI PCR specifies that the 100 year methodology for in-use products and EPA landfilling models be applied to determine the net sequestered carbon relative to the emissions of carbon dioxide and methane that occur at the end of life. Since these processes are not included in this LCA, the following presents only the carbon sequestered in the product at the manufacturing gate, and equivalent carbon dioxide that was consumed during the forest growth. This will allow for a future user of the data to add the gate-to-grave processes and calculate a carbon sequestration credit. The carbon sequestered in 1 m3 MDF at the manufacturing gate is: 673 oven dry kg (From mass balance Table 5) is equal to: kg C (assuming 50% carbon content) is equal to: kg CO2 eq. (assuming 44/12 molecular weight ratio) For a business-to-business EPD developed in accordance with the FPInnovations Wood PCR 2011, this carbon sequestration at the manufacturing gate may be included in the Additional Information section. 12 NPCR 015 September 2009, The Norwegian EPD Foundation Athena Sustainable Materials Institute 16

25 4 Data Sources and Averaging This section provides a brief description of the primary and secondary data sources used to complete the LCA. It also discusses how the data for the four MDF mills were integrated to provide a weighted average profile for Canada. 4.1 Primary and Secondary Data Sources There are three main system process accounted for in this LCA study. The first system process is upstream wood residues processing which includes production of by-products such as shavings, sawdust and chips by third-party suppliers. These raw wood inputs to MDF manufacturing are primarily categorized as by-products of lumber production. The second system process is wood residues and material transportation from suppliers/manufactures to MDF mills. Input materials include resin, wax, catalyst, scavenger, purchased hog fuels, lubricants, various oils, and greases transported to MDF mills. The third system process is the manufacturing of MDF in Canada. Upstream wood residues processing- the environmental load of wood residue inputs to the MDF plant (shavings, sawdust, chips, etc.) is based on other recent Institute studies 13. These data include a Canadian weighted average profile (based on mass allocation rules and methods) for shavings, sawdust and chips (by-products of lumber production system). Sanderdust and panel trim are byproducts of the MDF process itself. On average, the raw wood residues input consisted of 42% shavings, 35% sawdust, 21% chips and 2% internal sanderdust and panel trim. Wood residues and material transportation, from suppliers to MDF plants, was primarly via diesel tractor-trailer truck (DTTT). Other modes of transportation such as rail and pipe were used for resin, wax, catalyst and scavenger transportation- see Table 4. The study incorporated the appropriate US LCI modal transportation datasets ( for this system process. MDF manufacturing LCI data was gathered from four plants across the country in four provinces British Columbia, Alberta, Ontario and New Brunswick. Four surveyed mills provided data on a 2006 calendar year basis. The participating plants also provided information and data on the use of UF and/or MUF resins, wax, catalyst, scavenger and the ancillary inputs (e.g., lubricants, oils, greases, etc.) to their plants, including the transportation distance. New 2007 LCI data for the production of UF resin and scavenger (a byproduct of UF resin production) were provided by a Canadian UF resin manufacturer. These data were used in this LCA study. The slack wax LCI profile was adapted from the ecoinvent 2.2 database. Table 3 shows the secondary LCI data sources used in this LCA study. 13 A Cradle-to-Gate Life Cycle Assessment of Canadian Surfaced Dry Softwood Lumber: An Update, Prepared for: Canadian Wood Coucil, September Athena Sustainable Materials Institute 17

26 Table 3: Secondary LCI Data Sources Technosphere Input Diesel Truck Delivery Electricity Fiber Production Gasoline Hogfuel Hydraulic Fluid Lubricants Natural gas Propane LCI Data Source USLCI data for diesel transport, combination truck, diesel powered; pre- combustion dummy processes corrected Athena data for Canadian average % electricity source and line loss; USLCI data for combustion processes ATHENA cradle- to- gate mass- allocated production data for lumber coproducts (includes upstream harvesting and transportation) USLCI data for gasoline combusted in equipment; pre- combustion dummy processes corrected; NPRI substances removed in S3: MDF Manufacturing stage as these were accounted for separately as process emissions specific to emissions controls at the surveyed facilities CORRIM 12 data (based on AP42) for biomass combustion; normalized to oven- dried kg inputs and all technosphere inputs for wood production removed to reflect internal sourcing; NPRI substances removed in S3: MDF Manufacturing stage as these were accounted for separately as process emissions specific to emissions controls at the surveyed facilities USLCI data for gasoline production; pre- combustion dummy processes corrected USLCI data for gasoline production; pre- combustion dummy processes corrected USLCI data for natural gas combusted in boiler; pre- combustion dummy processes corrected; NPRI substances removed in S3: MDF Manufacturing stage as these were accounted for separately as process emissions specific to emissions controls at the surveyed facilities USLCI data for propane combusted in equipment; pre- combustion dummy processes corrected; NPRI substances removed in S3: MDF Manufacturing stage as these were accounted for separately as process emissions specific to emissions controls at the surveyed facilities Publication Year / / / Athena Sustainable Materials Institute 18

27 Steel Strapping Urea Formaldehyde Resin USLCI data for cold rolled sheet steel Canadian industry data Methodology for Averaging Data There are two methods available for integrating LCI data across an industry sample vertical or horizontal 14. Horizontal integration implies averaging the data across each unit or system process and then integrating through the supply or product chain. Vertical integration implies first integrating the data through the supply chain and then using a weighting factor, based on annual production data, to horizontally integrate the primary data. Based on the data availability, the horizontal approach is applied is this LCA study-see Figure 4 below. Average weighting factors were calculated as follows: Equation 1: w 1 = y 1 / (y 1 + y 2 + y 3 + y 4 )= y 1 / Y total w 1 (in %) = (y 1 / Y total ) * 100 where, Y total y 1 y 2 y 3 y 4 total annual production of four MDF mills (MSF 3/4 inch basis); MDF annual production of Mill 1 (MSF 3/4 inch basis); MDF annual production of Mill 2 (MSF 3/4 inch basis); MDF annual production of Mill 3 (MSF 3/4 inch basis); MDF annual production of Mill 4 (MSF 3/4 inch basis). For example, if the annual production of mill 1, 2, 3 and 4 are respectively 100, 200, 300 and 400 MSF 3/4-inch basis, the weighting factors for averaging would be w1=0.1, w2=0.2, w3=0.3 and w4=0.4, respectively (wtotal should always equals to 1 or 100%). 14 A detailed description of each method is given in: I Boustead: Eco-profiles of the European Plastics Industry, Methodology, Prepared for Plastics Europe; page 32. Athena Sustainable Materials Institute 19

28 Figure 4: Depiction of horizontal approach for averaging the Canadian MDF LCI Data Athena Sustainable Materials Institute 20

29 5 Life Cycle Inventory This section provides a general description of each system process in the production of MDF. It then presents a mass balance for the production of MDF products in Canada. 5.1 Upstream wood residues processing On average, the raw wood residues input consisted of 42% shavings, 35% sawdust, 21% chips and 2% MDF internal sanderdust and panel trim. Shavings, sawdust and chips are byproducts of Canadian lumber production system. None of the four mills reported using raw logs as an input material. Sanderdust and panel trim are byproducts of the MDF process itself. Canadian wood residues fibre sources used in the production of MDF consisted of 81 % softwood and 19 % hardwood species. The average input wood density was determined to be approximately 383 kg/m3 (volume green, weight oven dry) based on the species mix entering the MDF mills. 5.2 Resource and material transportation Table 4 below presents the weighted average transportation mode and distances for each of the raw material inputs used in the production of Canadian MDF. Transportation is calculated on a tonne-km basis; i.e., the energy necessary to move one tonne of material one km, by mode. The mass of raw wood fibre transported reflects wet wood (wood + moisture in wood). Table 4: Summary of Raw Material Transportation by Mode and Distance to MDF mills Ressource DTTT 1,2) Rail Pipe transportation (in km) % (in km) % (in km) % Wood residues % Resin(s) % % % Wax % % Catalyst % % Scavenger % % Hydraulic fluids, motor % oils, and greases Polyethylene sheets % MDF wrap % Purchased hog fuel % Steel strapping % 1) DTTT- Diesel Tractor Trailer Truck; 2) Empty backhaul included 5.3 MDF Manufacturing Mass Balance There are four main material input components for the production of MDF. These include wood fibre residues, urea formaldehyde (UF) and or methylurea-formaldehyde (MUF) resin, Athena Sustainable Materials Institute 21

30 wax and scavenger. On a percent mass basis, Canadian MDF is comprised of wood fiber (88.5%), resins (10.2%), wax (0.5%) and scavenger 0.7%. MDF production by-products include sanderdust and panel trim and are used on-site either as hogfuel (84%) or as product furnish reintroduced at the blowline (16%). Wood waste (about 1%) is either transferred to a landfill or is stockpiled on-site. All wood fibre flows in the MDF system were converted an oven-dry (OD) basis. The following formulas 15 were applied to prepare the mass balance: Moisture content on a oven dry basis is calculated by the following equation [14]: Equation 2: Alternately, wood moisture content may be expressed on a wet basis. Moisture content on a wet basis is calculated by the following equation [14]: Equation 3: Equation 4: The following formulas were applied to convert from wet basis to oven dry [14]: % Moisture Content (dry basis) = 100 % MC wet basis 100 % MC wet basis Based on the data provided by individual mills, the average range of moisture content of wood residues input was estimated to be between 30% to 57 % oven dry basis. The weighted average moisture content (MC %) was estimated to be 5.1 % on an oven-dry basis. This value is in the range with the American National Standards Institute (ANSI) Standard for wood, which is between 5-7% MC. 15 RTI International: Emission Factor Documentation for AP-42, Chapter 10, Plywood and Composite Wood Products, Final Background Report, Prepared for EPA, July Athena Sustainable Materials Institute 22

31 Table 5 provides a mass balance for Canadian MDF manufacturing on a horizontal weighted average basis for both 1m3 and 1,000 sq. ft. of MDF product (3/4- inch basis). Athena Sustainable Materials Institute 23

32 Table 5: Wood Mass balance for Canadian MDF Manufacture per m3 and MSF basis Input/Output per m 3, and MSF (3/4-inch basis) MDF Inputs Units per m 3 per MSF % Purchased wood residues kg 766 1,355 98% Sanderdust generated in house and used in process line Outputs Sanderdust and sawtrim (84% used internally as fuel, 16% in process line) kg % Total Inputs 782 1, % MDF (wood only) kg 673 1,191 86% kg % Wood waste kg % Total Outputs kg 782 1, % The mass balance indicates that 86% of the raw wood resource input ends up as the primary product (MDF). Another 13% of the incoming biomass is used as hogfuel or is recycled via the blowline and about 1% of the raw wood fibre input ends up as wood waste. The weighted average density of Canadian MDF was determined to be 761 kg/m3 (47 lb/ft3) inclusive of resin and scavenger Gate-to-Gate LCI of MDF manufacturing production system Table 6 presents the weighted average resource and energy inputs and the reported direct emissions to air and water and solid waste generated at the plant site for the production of MDF on a 1 m3 (19.05 mm basis) and 1000 square feet (¾-inch basis). Table 6: Gate-to-gate weighted average LCI flows of Canadian MDF manufacturing system (based on data provided by 4 Canadian MDF mills for 2006 calender year) Inputs/Outputs Unit Quantity per 1 MSF, 3/4-inch basis (1.77 m3) 1. Material input Wood residues 1) kg 1, Sanderdust generated in house 1) kg UF Resin 2) kg MUF resin 2) kg Wax 2) kg Quantity per 1 m3, mm basis Athena Sustainable Materials Institute 24

33 Inputs/Outputs Unit Quantity per 1 MSF, 3/4-inch basis (1.77 m3) Catalyst 2) kg Scavenger 2) kg Hydraulic fluids Liter Motor oils Liter Greases kg Steel strapping kg Polyethylene sheets m MDF wrap m Energy input Electricity (purchased) kwh Electricity (generated) kwh 0 0 Liquid Propane Gas (LPG) 3) Liter Gasoline 3) Liter Diesel Fuel 3) Liter Natural Gas m Hogfuel (generated and used inhouse) kg ) Purchased Hogfuel kg Purchased Steam MJ Water use Surface Water (Input) m Groundwater (Input) m Water discharged (output) m Water recycled m Water consumption m Product & by-products MDF product kg 1, Quantity per 1 m3, mm basis MDF 1) - wood only kg 1, Sanderdust, saw trims 1), 4) kg Sanderdust (in blowline) kg Athena Sustainable Materials Institute 25

34 Inputs/Outputs Unit Quantity per 1 MSF, 3/4-inch basis (1.77 m3) Hogfuel (in-house) kg 150 Quantity per 1 m3, mm basis Air Emissions (NPRI data- on-site process and fuel combustion only) Total Particulates kg Particulates =<10 pm kg Particulates =<2.5 pm kg Oxides of Nitrogen (NOx) kg Carbon monoxide (CO) kg Total VOCs kg Phenol kg Formaldehyde kg Methanol kg Acrolien kg Acetaldehyde kg Propionaldehyde kg 2.4E E-05 Lead kg 1.2E E Water Effluents 6) Suspended Solids kg Chemical Oxygen Demand (COD) kg Solid Waste 6) Wood waste kg Heater and fly ash waste kg Solid waste (unspecified) kg All wood fiber weights (inputs/outputs) are reported on oven dry basis. 2. Resin, wax, catalyst and scavenger weights are reported at 100% solids; solids content as reported by mills were UF resin ( %), wax (57-58%), catalyst (100%) and scavenger (50-59%). 3. LPG, gasoline and diesel fuel (80%) are used to run on-site mobile equipment. 4. Canadian MDF mills reported byproducts under sanderdust and sawtrims which are fuly utilized on-site. 5. Water intake and discharge present the water flows in and out the MDF mills only. 6. Air, water and solid waste emissions represent reported on-site (process and combustion) emissions only Athena Sustainable Materials Institute 26

35 6 Life Cycle Impact Assessment, Use of resources and Generation of waste This section discusses the cradle-to-gate results for the declared unit in terms of the selected life cycle impact assessment (LCIA) indicators, use of resources and generation of waste (see Table 2). Tables 7 and 8 present the LCIA absolute and percent results for the cradle-to-gate life stages in the production of MDF. The MDF manufacturing stage (S3) consumes the most fossil and bioenergy and is the greatest contributor to impacts in every impact category. The portion of global warming caused by this life stage (81%) closely matches the consumption of fossil fuels (85%) and the smog, eutrophication, and acidification are also dominated by manufacturing (83%-94%). Table 7: LCIA Results Summary for Cradle-to-Gate production of 1 m 3 of MDF absolute basis (mass allocation, unit process approach) Impact category Unit Total S1: Wood residues processing S2: Resource transportation S3: MDF Manufacturing Global Warming kg CO2 eq Acidification H+ moles eq Eutrophication kg N eq 2.80E E E E- 01 Smog kg O3 eq Ozone Depletion kg CFC- 11 eq 1.40E E E E- 09 Total Primary Energy Consumption Non renewable, fossil MJ 7, , Non- renewable, nuclear MJ Renewable, biomass MJ 2, , Renewable (solar, wind, hydroelectric and geothermal) MJ 1, , Feedstock, renewable 16 MJ 13, , FPInnovations PCR (2011): Section 9.1, pg 11, Notes for Table 3, item 4 The heating value of the wood building product itself (feedstock energy, renewable) should be reported separately from other renewable primary energy on a higher heating value (HHV) basis. Feedstock energy, renewable is calculated by multiplying 673 kg wood/m3 MDF by 20MJ/kg (HHV). Athena Sustainable Materials Institute 27

36 Table 8: LCIA Results Summary for Cradle-to-Gate production of 1 m 3 of MDF percentage basis (mass allocation, unit process approach) Impact category Total S1: Wood residues processing S2: Resource transportation S3: MDF Manufacturing Global Warming 100% 12% 7% 81% Acidification 100% 5% 4% 91% Eutrophication 100% 2% 4% 94% Smog 100% 7% 10% 83% Ozone Depletion 100% 30% 8% 62% Total Primary Energy Consumption Non renewable, fossil 100% 9% 5% 85% Non- renewable, nuclear 100% 7% 0% 92% Renewable, biomass 100% 1% 0% 99% Renewable (solar, wind, hydroelectric and geothermal) 100% 7% 0% 93% Feedstock, renewable 100% 0% 0% 100% Tables 9 and 10 present the use of resources and generation of waste results for the cradle-togate life stages in the production of MDF on an absolute and percent basis, respectively. These inventory values are not characterized by any impact assessment factors. Water use was broken down into water withdrawal and water consumption as defined by SETAC 17 and in-stream water use (water flowing through turbines in hydroelectric plants) was excluded from both metrics. Water consumption was estimated as the percentage of evaporative loss for cooling and process water based on the default values that will be applied in the forthcoming ecoinvent v3 18. Cooling water and process water use result in different evaporative loss and thus should be distinguished in LCI accounting for consumption. In some unit processes, the differentiation is made, but in the others a default breakdown was applied. Process: 80% of unclassified water Cooling: 20% of unclassified water Once the water use has been assigned to one of these categories, the consumption factors are applied. These consumption factors are: Process: 15% consumption factor Cooling: 50% consumption factor 17 Bayart JB, Bulle C, Deschênes L, Margni M, Pfister S, Vince F, Koehler A (2010) A framework for assessing off- stream freshwater use in LCA. Int J Life Cycle Assess 15: Athena Sustainable Materials Institute 28

37 For the gate-to-gate MDF manufacturing process, the consumption was calculated based on the actual consumption of water resource specified in Table 6. Table 9: LCI Parameters Required by Wood PCR absolute basis (mass allocation, unit process approach) Use of Material Resources and Generation of Waste Units Total S1 Mass: Forestry, harvesting, fiber production S2 Mass: Resource transportation S3 Mass: MDF manufacturing Material resources consumption Renewable materials- wood fiber kg 7.82E E E E+01 Non- renewable materials kg 1.43E E E E+00 Fresh water Water withdrawal l 9.48E E E E+02 Water consumption l 3.92E E E E+02 Waste generated 19 Hazardous Waste kg None Non- Hazardous Waste Wood waste kg 2.45E E E E+00 Unspecified waste kg 2.60E E E E+00 Fly ash kg 3.24E E E E FPInnovations PCR (2011): Section 9.1, pg 11, Notes for Table 3, item 5 Waste should be declared as either hazardous or non-hazardous. Athena Sustainable Materials Institute 29

38 Table 10: LCI Elements Required by Wood PCR percentage basis (mass allocation, unit process approach) Use of Material Resources and Generation of Waste Total S1 Mass: Forestry, harvesting, fiber production S2 Mass: Resource transportation S3 Mass: MDF manufacturing Material resources consumption Renewable materials- wood fiber 100% 98% 0% 2% Non- renewable resources 100% 27% 0% 73% Fresh water Water withdrawal 100% 6% 0% 94% Water consumption 100% 9% 0% 91% Waste generated Hazardous Waste None Non- Hazardous Waste Wood waste 100% 66% 0% 34% Unspecified waste 100% 59% 0% 41% Fly ash 100% 0% 0% 100% Athena Sustainable Materials Institute 30

39 7 Life Cycle Interpretation Interpretation is the phase of LCA in which the findings from the inventory analysis and the impact assessment are brought together and significant issues are identified and considered in the context of the study goal and scope. In addition, the study s completeness, consistency of all applied information, and sensitivity to key assumptions or parameters as they relate to the goal and scope of the study, are evaluated. Lastly, the interpretation phase ends by drawing conclusions, stating the study s limitations and making recommendations for further study (as per Clause , ISO 14044:2006). 7.1 Identification of the significant issues Based on established LCA practices, contribution analysis was applied for the interpretation phase of this study. Contribution analysis examines the contribution of life cycle stages, groups of processes or specific substances to the total results [4]. The previous section of this report detailed the key contributing life cycle stages for MDF manufacturing product system. In this section, the contribution analysis was focused on the contributing unit processes of the MDF manufacturing system and the examination of the major contributing flows for each of the selected impact indicators categories Unit processes Contribution Analysis Tables 11 and 12 present the LCIA absolute and percent results for the unit processes that comprise the MDF manufacturing life stage (S3). The wood preparation unit process (SU1) consumes the most fossil and biomass energy and is the greatest contributor to impacts in every impact category. The drying unit process (SU2) also draws heavily on internally generated and externally purchased hogfuel. The ozone depletion potential is less less than 10-8 kg CFC-11 eq. and is thus insignificant overall. Table 11: Unit Process Contribution Analysis for Manufacturing (S3) of 1 m3 of MDF absolute basis (mass allocation, unit process approach) Impact category Unit Total SU1: Wood preparation SU2: Drying SU3: Board shaping SU4: Board finishing Global Warming kg CO2 eq Acidification H+ moles eq Eutrophication kg N eq 2.64E E E E E- 04 Smog kg O3 eq Ozone Depletion kg CFC- 11 eq 8.70E E E E E- 09 Total Primary Energy Consumption Non renewable, fossil MJ 6, , , Non- renewable, nuclear MJ Renewable, biomass MJ 2, , Renewable (solar, wind, hydroelectric and geothermal) MJ 1, Athena Sustainable Materials Institute 31

40 Table 12: Unit Process Contribution Analysis for (S3) of 1 m3 of MDF percentage basis (mass allocation, unit process approach) Impact category Total SU1: Wood preparation SU2: Drying SU3: Board shaping SU4: Board finishing Global Warming 100% 62% 25% 7% 6% Acidification 100% 69% 22% 6% 3% Eutrophication 100% 55% 36% 8% 0% Smog 100% 51% 36% 10% 3% Ozone Depletion 100% 38% 3% 6% 54% Total Primary Energy Consumption Non renewable, fossil 100% 71% 20% 5% 4% Non- renewable, nuclear 100% 74% 4% 13% 9% Renewable, biomass 100% 56% 31% 13% 0% Renewable (solar, wind, hydroelectric and geothermal) 100% 73% 4% 13% 9% Substance Contribution Analysis The previous section discussed how each of the three stages and manufacturing unit processes contribute to each of the impact indicators for the cradle-to-gate MDF profile. However, these previous tables do not show how each of the substance releases within each of the system processes contributes to each of the impact indicators. Often by highlighting key contribution substances a more focussed approach to improving the contributing process can be undertaken. For example, Table 13 below shows the degree to which various greenhouse gases contribute to the global warming potential impact indicator across the three system processes. As already identified, the primary system process contributing to the indicator is MDF manufacturing itself (81%) - see Table 8. What the substance contribution table shows is that within the MDF manufacturing process, it is the carbon dioxide from fossil fuels that are the primary contributors to the global warming impact contributing 89% to the cradle-to-gate total (Table 13). Appendix A summarizes the substance contribution analysis for each of the other impact indicators. Athena Sustainable Materials Institute 32

41 Table 13: Substance Contribution Analysis to Global Warming Potential by Life Stage - % basis displays relative values vertically (within processes)- for MDF Substance Compartment Unit Total S1 Mass: Forestry, harvesting, fiber production S2 Mass: Resource transportation S3 Mass: MDF manufacturing Total of all compartments % Carbon dioxide Air % Methane Air % Dinitrogen monoxide Air % Remaining substances % Completeness, Consistency and Sensitivity Checks Evaluating the study s completeness, consistency and sensitivity helps to establish and enhance confidence in, and the reliability of, the results of the LCA study, including the significant issues identified in the first element of the interpretation [4]. The objective of the completeness check is to ensure that all relevant information and data needed for the interpretation are available and complete [4]. Three selected life cycle stages ( Forestry, harvesting, fiber production, resource transportation and MDF manufacturing ) and the four MDF manufacturing unit processes (SU1: Wood preparation, SU2: Drying, SU3: Board shaping, SU4: Board finishing) were checked for data completeness including all elements such as raw and ancillary material input, energy input, transportation, water consumption, product and co-products outputs, emissions to air, water and land and waste disposal. All the input and output data were found to be complete and no data gaps were identified. The objective of the consistency check is to determine whether the assumptions, methods, models and data are consistent with the goal and scope of the study [4]. Through a rigorous process, consistency is ensured to fullfill the goal of the study in terms of assumptions, methods, models and data quality including data source, accuracy, data age, time-related coverage, technology and geographical coverage. Sensitivity analysis tries to determine the influence of variations in assumptions, methods and data on the results of the study [4]. Sensitivity analysis is a procedural comparison of the results obtained using baseline assumptions, methods or data with the results obtained using altered assumptions, methods or data. For this study we completed a sensitivity analysis contrasting the mass allocation method as employed in this study update - with that of applying a economic based allocation method. Athena Sustainable Materials Institute 33

42 MDF is a single-output process and thus no allocation was applied to the manufacturing gateto-gate process. The wood fiber input, however, is the product of the multi-output manufacturing system for softwood lumber. Softwood lumber manufacturing results in multiple valuable primary products (rough green, surfaced green and surfaced dry) and byproducts (pulp chips, planer shavings, sawdust, etc.). When using economic allocation, the total environmental burden of the total manufacturing system is "shared" between the primary product (e.g., softwood lumber) and the co-products of production (e.g. pulpchips, sawdust, planer shavings etc.) based on the share of each product/co-product contribution to total sales or proceeds of the multi-functional process traced back to the cradle. The proceeds are based on average prices provided by the participating mills per unit of primary product and co-products. Table 14 summarizes the LCIA results for the cradle-to-gate MDF with the fiber input based on an economic allocation applied to the wood fiber cradle-to-gate product system. Table 14: LCIA Results Summary for Cradle-to-Gate production of 1 m3 of MDF absolute basis (economic allocation, unit process approach) S1 Econ: Impact category Unit Total Forestry, S2 Econ: S3 Econ: MDF harvesting, Resource manufacturing fiber transportation production Global Warming kg CO2 eq Acidification H+ moles eq Eutrophication kg N eq 2.74E E E E- 01 Smog kg O3 eq Ozone Depletion kg CFC- 11 eq 1.15E E E E- 09 Total Primary Energy Consumption Non renewable, fossil MJ 7, , Non- renewable, nuclear MJ Renewable, biomass MJ 2, , Renewable (solar, wind, hydroelectric and geothermal) MJ 1, , Feedstock, renewable MJ 13, , Figure 5 graphically displays the two allocation methodologies side by side across the various LCIA indicators developed and supported for this study. Reviewing Figure 5, it is apparent that using economic allocation as opposed to mass allocation reduces impacts by roughly 3-15% across the various impact categories. That is, more of the environmental burden is allocated to the lumber manufacturing co-products (and MDF inputs) using mass allocation then when using economic allocation. Athena Sustainable Materials Institute 34

43 Figure 5: Sensitivity Analysis Results Mass vs. Economic Allocation 7.3 Conclusions, limitations and recommendations This study provides a comprehensive cradle-to-gate LCA of the Canadian industry s production of MDF products. The primary goal of this LCA was to develop life cycle inventory data and impact assessment results for MDF that could be used to develop EPD s in accordance with FPInnovations Wood PCR In addition to the impact assessment results, the life cycle inventory elements are also provided. Including the LCI elements enables the resource use inventory elements and waste flows as required by the PCR to be included in the EPD. This cradle-to-gate LCA does incorporate the necessary scope to develop a business-to-business EPD in accordance with FPInnovations Wood PCR The manufacturing activity stage, and particularly the drying and board shaping unit processes, drives the life cycle profile for MDF; both fiber production and resource transportation to the mill account for only a minor share of the environmental impact for the product. Bio-based energy substantially reduces the global warming potential from the drying unit process, but does not eliminate the MDF plants total GWP contribution due to the use of fossil fuels directly or indirectly via purchased electricity. Increased use of renewable biomass would further reduce the overall use of fossil energy (especially natural gas use) and the GWP impacts from the industry. Topics for further investigation include: 1) modeling the use and end-of-life phases of the product; and 2) determining the influence of substituting more renewable biomass on fossil fuel use and how this may effect overall co-product supply to other end users of the industry s coproducts. FPInnovations Wood PCR 2011 also requires additional information related to environmental issues that are beyond the scope of this LCA. This information includes impacts to forest biodiversity and any other environmental certifications that may apply to the product. Athena Sustainable Materials Institute 35