Title: A Practical Methodology for Biorefinery Product Chain Environmental Analysis Using Life Cycle Assessment

Transcription

1 PROJECT Title: A Practical Methodology for Biorefinery Product Chain Environmental Analysis Using Life Cycle Assessment Project Start Date: July 01, 2013 Estimated Completion Date: June 30, 2014 Name of Principal Investigator: Paul Stuart Names of Co-Investigator: Institution: École Polytechnique de Montréal Institution: Name of FPInnovations Liaison (FPInnovations contact): Lal Mahalle Network Research Theme: Theme II/III HQP (Ph.D., Master s, PDF, Internship) : PDF Student name : Zahra Sarshar- Zahra.sarshar@polymtl.ca Available immediately Executive Summary Developing an LCA in general is resource intensive and typically requires many months to complete. On the other hand, the idea of a simplified LCA raises concerns because if LCA is not rigorously performed, the results could be potentially misinterpreted for this methodology that despite ISO guidelines is considered subjective by many. The goal of this project is to criticallyreview pre-existing methodological and case study work completed at École Polytechnique, in order to identify a rules-based or heuristically-based LCA methodology suitable as practical method for biorefinery evaluation. Should this methodology be transferred to industry, LCA practitioners would be able to more quickly evaluate the environmental performance of different biorefinery options. Background Various approaches have been developed to perform the environmental evaluation of biorefinery processes, for example: Environmental Impact Assessment (EIA): A methodology for determining the environmental, social and other consequences of a given project, focusing on the impact in the receiving environment considering air, water and solid waste discharges. Regulatory Requirements: Estimation of the process emissions and comparison of these with provincial and federal government regulations and other requirements. Best Available Technology (BAT) Analysis: BAT refers to the assessment of the process technology and associated emissions, compared to best practices considering both design and operations [1]. Life Cycle Assessment (LCA): LCA assesses the potential impacts from products and services using a life cycle perspective. The holistic environmental perspective that LCA provides on products has made it invaluable for environmental management in industry, and environmental policy-making in government [2].

2 EIA, regulatory evaluation, and BAT are project- and site-specific approaches, whereas, life cycle assessment is generally a site-generic approach. LCA is a cradle to grave approach considering the entire product chain from raw material acquisition to end-of-life, compiling all the inputs and outputs existing in the life cycle, and evaluating their potential environmental impact [3]. By considering impacts throughout the product life cycle, LCA provides a comprehensive view of the environmental trade-offs for different biorefinery processes. Moreover, by interpreting the results of the evaluations, LCA can be employed to help decision-makers for making more informed decisions [4]. The biorefinery product chain could be environmentally preferable or not depending on the biorefinery process, and the particular manner it is implemented. It is critical to evaluate the environmental preference of the products manufactured from different biorefinery options, in order to use and integrate the results in multi-criteria decision making (MCDM) along with economical and social criteria for possible biorefinery strategies. Life Cycle Assessment (LCA) is the only generally-accepted approach for evaluating the environmental preference of products produced from biorefinery processes however the method of LCA application for the portfolio of bioproducts is (a) not wellunderstood or well-defined, as well as (b) complex, resource intensive, time-consuming, and expensive. As illustrated in Figure 1, the standard framework of LCA methodology has four steps, including goal and scope definition, inventory analysis, impact assessment and interpretation [2] Figure 1. Standard Life Cycle Assessment Framework For the biorefinery, LCA can be used to evaluate replacing fossil-based products and fuels by bioproducts. If LCA is correctly applied, it can be used to demonstrate the environmental impact due to different biomass feedstocks, emerging conversion technologies and potential biorefinery products. The comparison of the environmental performance of possible biorefinery strategies can play a significant role in distinguishing between promising options, especially in the context of multi-criteria decision-making (MCDM) [5]. The main steps considered in a life cycle assessment of a biorefinery process are presented in Figure 2.

3 Figure 2. Main Steps in the Life Cycle of a Biorefinery process. The detailed LCA approach has been extensively-applied by the systems analysis research team at École Polytechnique, including specifically for evaluating biorefinery process-product options. Cornejo Rojas [6] proposed a tool to enhance Environmental Impact Assessments (EIA) of new process design alternatives by integrating Life Cycle Assessment (LCA) considerations into EIA in order to be able to execute a broader environmental analysis. An MCDM was performed based on different EIA and LCA criteria and results in this work. He demonstrated that Environmental Impact Assessment (EIA) can be enhanced by including Life Cycle Assessment (LCA) elements in the overall evaluation of the proposed design alternatives by showing different trends for LCA and EIA results. He also showed that at the product-chain level (related to LCA), there are important environmental benefits such as the reduction of current global, regional and local impact levels. Gaudreault et al. [7] reviewed LCA applications in the pulp and paper industry, and identified opportunities for improvement of LCA methodologies using consequential analysis. She evaluated short- and long-term environmental criteria for pulp and paper mills using consequential LCA. In this work, the principles of MCDM and the method of establishing a coherent family of criteria are applied to rank the environmental aspects according to their significance. She developed an LCM (life cycle management) framework which improves EMS by including LCA and MCDM which allows the proposal of relevant environmental improvement projects and the evaluation of the impact of other projects of the organization (tactical and strategic). A new normalization method based on the distance-to-target concept (where the target is defined using the best available technologies) was also developed. Liard et al. [8] conducted an environmental assessment of the Triticale-based biorefinery using LCA. She carried out Multi-Criteria Decision-Making (MCDM) panel studies in order to identify the most representative, comprehensive and interpretable environmental criteria. These environmental criteria along with technical, economic and commercial criteria were considered in the decision-making process for the development of riticalebased biorefinery. More recently in ongoing work, Batsy et al. [9] performed the environmental assessment of the forest biorefinery product portfolio using detailed and rigorous LCA analysis. He implemented the consequential LCA and cut-off procedure in his LCA methodology. Furthermore, he conducted an MCDM panel for identification of a set of practical and interpretable environmental criteria for evaluating a set of biorefinery strategies for a forestry company. Despite the strength of rigorous LCA methodology, it has limitations. Due to its meticulous nature, it requires a large amount of data, is time-consuming and expensive. If incorrectly applied, LCA can give skewed or erroneous results.

4 There are a host of decisions associated with applying appropriate LCA methodology including data quality, system boundary establishment, product functionality, allocation approach to assign environmental impacts to multiple products, selection of impact assessment method, weighting of different impact categories, temporal and special resolution, and others [10]. Particularly for evaluating biorefinery processes, there is limited information in the literature regarding environmental impacts including important issues such as indirect land use change, acidification, eutrophication, ozone depletion and toxicity [5]. In particular related to biorefinery decisionmaking, important challenges concern defining the proper normalization method, and interpreting environmental criteria used in an MCDM panel. Depending on the study context, environmental assessment can also be accomplished based on heuristic approaches. By implicating a fundamental understanding of processes, context-based and impact-based simplifications can be performed for the purpose of heuristically-based LCA. Context-based simplifications of the process are based on the development of simplified mass and energy balances, in other words during the life cycle inventory step of LCA. Impact-based simplifications are more complex, and have been achieved in models such as GHGenius and GREET. GHGenius is a life cycle assessment model capable of analyzing the emissions of contaminants associated with the production and use of traditional and alternative transportation fuels. It has been developed for Natural Resources Canada over the past years and is based on the 1998 version of Mark Delucchi s life cycle emission model. GHGenius can perform LCA with data for specific regions. All of the steps in the life cycle are included in the model, from raw material acquisition to end-use. Although it is transportation specific, it covers most energy sources and many materials manufacturing processes and land use changes [11]. GREET,(Greenhouse gases, Regulated Emissions and Energy use in Transportation) is a full life cycle model that has been developed by the Argonne National Laboratory in the USA to evaluate energy and emission impacts of advanced and new transportation fuels. The fuel cycle from wellto-wheels, and the vehicle cycle from material acquisition to vehicle disposal are considered in this model [12]. The focus of both these models has been on estimating life cycle emissions for three calculated criteria: greenhouse gases, pollutants from combustion sources, and energy consumed. These models calculate the consumption of total energy, fossil fuels, emissions of CO2-equivalent greenhouse gases, emissions of six criteria pollutants i.e. Volatile Organic Compounds (VOC), carbon monoxide, nitrogen oxide, particulate matters with sizes smaller than 10 and 2.5 micrometer, and sulfur oxide. In this project, a practical LCA methodology is sought for the evaluation of biorefinery processes more broadly including non-biofuel bioproducts, and considering the product portfolio. The methodology should be responsible: transparent and comprehensive, and the limitations of the approach should be evaluated and explicit. The heuristic approach to be developed can be achieved by incorporating context-based simplifications of biorefinery processes, and in particular, parameters that affect the mass and energy balances. The heuristic approach can also consider ways that Life Cycle Impact Assessment (LCIA) can be performed heuristically (impact-based simplification), so that targeted impact categories are considered for biorefinery evaluation. For example, LCA-based models such as GHGenius or GREET have been used for simplified impact assessment. The comparison between rigorous and heuristic LCA methodology is shown in Figure 3. In the example presented, the rigorous LCA approach begins with data collection for the process, along with definition of the goal and scope, system boundaries, functional unit and more importantly definition of the rigorous LCA methodology. The rigorous methodology includes the implementation of cut-off

5 procedure, consequential LCA for the product portfolio, attributional LCA for individual products and definition of proper normalization method. The execution of the rigorous LCA including the development of mass and energy balances using data from various sources (literature review, data from site and information from the technology providers) and especially through close collaboration with the project team developing the process, and performing rigorous LCI and LCIA in order to obtain the results. Then, the environmental results are required to be normalized by using a proper normalization method. An MCDM will be conducted to weigh the resulting environmental impacts. In the heuristic LCA approach, the preliminary steps are the same as for rigorous LCA except for the methodology definition. In other words, the heuristically-based methodology can be characterized by incorporating the context-based and impact-based simplifications along with the implementation of the above-mentioned procedures and methods of the rigorous methodology. The heuristic LCA methodology will be executed by developing a context-based and simplified mass and energy balances using the data from rigorous analysis. The inventory from the simplified mass and energy balances will be used to perform the environmental impact assessment, using models like Simapro. The results of the LCI and LCIA stages of the heuristic approach will be systematically compared with the corresponding results from the rigorous LCA method. This comparison can be used as a proper basis for refining the heuristically-based methodology. Also, Impact-based simplification can be achieved by using approaches similar to GHGenius or GREET. The results of the environmental impact assessment from these models can be compared with rigorous models like Simapro. This comparison will lead to the definition of the strength, weaknesses, benefits and limitations of these simplified methodologies.

6 Figure 3. Comparison of Rigorous and Heuristic LCA Methodologies

7 Objectives 1) To critically analyze previous methodological and case study work for the LCA evaluation of energy and biorefinery projects. 2) To critically analyze the GHGenius and GREET model approaches established for biofuels. 3) To propose the heuristically-based methodology for practical LCA method. 4) To identify the case study (likely one addressed in earlier work) and to evaluate the results of heuristically-based LCA. 5) 5) To write a review article introducing a methodology and finally, presentation to VCO network. Schedule of Milestones and Deliverables Year Milestones/Deliverable Expected Delivery Date Milestone: Literature review of the methodology and case studies for LCA biorefinery evaluation August Milestone: Critical analysis of GHGenius and GREET models for LCA of biofuels Milestone: Definition of the heuristically-based methodology based on literature review and critical analysis of both models Milestone: Evaluation of the results obtained from using rigorous and heuristically-based LCA methodology for a specific case study October 2013 December 2013 March Deliverable: Review article introducing a methodology May 2014 Deliverable: Presentation to VCO network June 2014

8 References [1] James L., Definition of Best Available Techniques, European directive on industrial emissions (2010). [2] Baumann H, Tillman A-M, The Hitch Hiker s guide to LCA, Lund, Sweden, p.20 (2004). [3] International Standard Organization, ISO 14040:2006; Environmental management - Life cycle assessment - Principles and framework. [4] Curran M-A. Life Cycle Assessment: principles and practice. By Scientific Applications International Corporation (SAIC). Cincinnati, OH. (2006). [5] Stuart P., El-Halwagi M. Integrated Biorefineries: Design, Analysis, and Optimization, LCA-based environmental evaluation of biorefinery projects, (2012.) [6] Corenjo Rojas F.A., Using Life Cycle Assessment as a Tool to Enhance Environmental Impact Assessment with a Case Study Application in the Pulp and Paper Industry, MSc. Thesis, École Polytechnique de Montréal (2005). [7] Gaudreault C. Samson R. Stuart P. Life cycle thinking in the pulp and paper industry, part 2:LCA studies and opportunities for development, TAPPI journal, Vol.6, No.8 (2007). [8] Liard G. Samson R. Stuart P. Systematic assessment of Triticale-based biorefinery strategies: Environmental evaluation using Life Cycle Assessment. Biofuels, Bioproduct and Biorefining (2011). [9] Romaric Batsy D. Environmental Impact Assessment of Forest Biorefinery Product Portfolio, Unpublished work, École Polytechnique de Montreal, Canada (2011). [10] H. Bos and K. Meester, Sustainability evaluation of high value-added products models, (2008). [11] S & T Consultants Inc. Introduction to lifecycle analysis and GHGenius, prepared for Natural Resources Canada (2006). [12] Wang M., Biofuel lifecycle analysis with the GREET model, Center for Transportation Research, Argonne National Laboratory (2011).