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Applying Life Cycle Assessment (LCA) in Process Industry—The Chemours Experience
Applying Life Cycle Assessment (LCA) in Process IndustrydThe Chemours Experience Shaibal Roy, Chemours Company, Wilmington, DE, United States Ó 2017 Elsevier Inc. All rights reserved.
Introduction Sustainability has arrived in the mainstream market. Major corporations have set sustainability goals, and have taken steps to meet those goals by improving their processes, products, and supply chains. DuPont, from where Chemours spun off as an independent company in 2015, for example, has published sustainability report for the last 25 years documenting its contribution to environmentally sustainable practices (DuPont Sustainability Report, 2015). During this time its sustainability focus has grown from managing operational footprint to helping its customers lighten their environmental footprint across the value chain. The shift is driven by both governmental and nongovernmental bodies, but also through greater awareness among consumers. Customers are demanding a product that conserves energy and water during manufacturing and use, requires less material to produce and produces minimal waste and have other minimal environmentally detrimental characteristics. Life cycle assessment (LCA) is a tool that provides a holistic quantification of a product’s environmental footprint along the entire supply chain, illustrated in Fig. 1. For systems of interest in process industry, the life cycle steps include extracting raw material from nature, preprocessing and manufacturing, distribution of materials at various stages, use of the product, and its eventual end-of-life through land filling, incineration, or recycling. The methodology and use of LCA has been published extensively in open literature (Schenck and White, 2014; PRe training manual, 2016). In summary ISO 14040/14044 provides the guiding steps for performing LCA (International Organization of Standardization, 2006a,b). Following the ISO guidelines provide LCA practitioners and users consistency in use and interpretation of the analysis originating from various sources and helps in comparing two or more products with similar functions. There are four main steps in LCA as shown in Fig. 2A. In the “Goal and Scope Definition step” the objective of the study as well as the boundary and content of the study is decided. The standard questions such as why, how, what, etc., are discussed in detail. All stakeholders are engaged in the process to arrive at a consensus. The “Inventory Analysis” step is the most involved and time-consuming steps of all. In this step, all relevant inventories of inputs such as material and energy use and the material release to the environment are compiled. For new processes, extensive process modeling is performed to generate the inventory data, whereas for an existing product, the plant data is normally used. In the “Impact Assessment” step, the compiled data is used to calculate potential environmental impacts. The conversion of inventory data to impact assessment can be accomplished in spreadsheet, but most often canned software (SimaPro 8 tutorial manual, 2016; GaBi manual, 2016.) are used to handle the large amount of data involved. A sample list of impact assessments is shown in Fig. 2B. The midpoint impact category is a problem-oriented approach that translates impacts into environmental themes such as climate change, acidification, human toxicity, etc. Using appropriate weighing factors, the midpoint impact assessments can be converted into endpoint impact category, also known as the damage-oriented approach. Endpoint translates environmental impacts into issues of concern such as human health, natural environment, and natural resources. LCA, as a tool to quantify environmental impacts, has wide applicability in industry. Corporations use LCA to develop sustainable business strategies by identifying direct and indirect emissions, as outlined by The Greenhouse Gas Protocol (The Greenhouse Gas Protocol, n.d.) for corporations. Based on LCA, the most environmentally friendly raw materials and utilities can be identified,
Fig. 1
Life cycle stages of a product.
Encyclopedia of Sustainable Technologies, Volume 1
http://dx.doi.org/10.1016/B978-0-12-409548-9.10073-9
357
358
Fig. 2
Applying Life Cycle Assessment (LCA) in Process IndustrydThe Chemours Experience
(A) The phases of life cycle assessment study. (B) Sample list of impact assessments.
and the best end-of-life process can be executed. LCA is also used, in addition to economics, to decide the best process to convert an idea to a product by selecting a technology that optimizes the environmental and economic gains. LCA has also proven to be a great marketing tool where manufacturers highlight competitive edge in markets where customers demand more environmentally friendly products.
The Chemours Initiatives Chemours as well as its mother company DuPont have extensively used LCA for most of the hundreds of new products it launches each year. LCA has been used to develop new application of Chemours’ products in building and construction (Roy et al., 2012), food and beverage storage (internal memo, work in progress), household appliances (Roy et al., 2013), and many others. LCA has also been used to improve the operations within the company fence line, explore alternate raw material as well as to improve the supply chain for materials and energy for an overall reduction in environmental footprint. By demonstrating sustainability through LCA, Chemours has extensively used LCA reports for product differentiation and marketing in technical and industrial forums. In this article, two such examples will be discussed with an aim to encourage readers to incorporate life cycle thinking in their normal work stream.
Process Improvement Through LCA: Titanium Dioxide Chemours is a leading manufacturer of titanium dioxide (TiO2), a whitening pigment used in paints, plastics, laminates, and papers. Chemours manufactures TiO2 using chloride process to convert Ti bearing ore into various grades of TiO2. Significant amounts of chemicals and energy are required in the manufacturing process. Therefore, TiO2 manufacturers have been especially mindful of its environmental footprint, and have strived to achieve high sustainability in their processes (Titanium Dioxide Manufacturers Association, 2016). Responding to customer requests for environmental footprint data, the Titanium Dioxide Manufacturers Association (TDMA) developed a rigorous titanium dioxide product footprint accounting and reporting method and published representative average
Applying Life Cycle Assessment (LCA) in Process IndustrydThe Chemours Experience
359
data for the 2010 and 2012 cradle-to-gate carbon footprint of titanium dioxide manufacture (The Carbon Footprint of Titanium Dioxide Pigment, n.d.). In 2014, TDMA expanded this footprinting method to compile a robust and representative cradle-togate life cycle inventory (LCI) of titanium dioxide manufacture in 2012. The LCI data set was externally reviewed and is now freely available in the European Life Cycle Data Base ELCD (TDMA Life Cycle, n.d.). The inventory data is representative of 33 TiO2 manufacturing sites from 9 companies including Chemours, covering more than 50% of the world production. Carbon footprint was the primary impact assessment evaluated, however, other impacts were also studied. Chemours is an associate member of TDMA. Chemours has extensively contributed to the development of the industry LCI data by providing representative data from its TiO2 manufacturing sites. The impact assessment published by TDMA is representative of the environmental footprint of Chemours TiO2 manufacturing process. The industry average cycle climate change potential (CCP) is 5.78 kg CO2/kg TiO2. The distribution of various inputs to the TiO2 manufacturing process to the life cycle CCP is shown in Fig. 3. It is clear from the above figure that the ore, energy, and site emissions related to the use of energy, as well as the chemicals used at various places in the manufacturing process contribute significantly to the overall CCP. In the last few years, Chemours has undertaken a number of projects to manage its process steps and supply chains to reduce its CCP and the overall industry footprint. Some of the steps include: Titanium ore type: Beneficiated ores such as slag and synthetic rutile has a high CCP compared to mined rutile, as shown in Fig. 4. Chemours has undertaken steps to reduce the usage of beneficiated ores. On a life cycle basis, this has resulted in an average decrease in CCP per kg of TiO2 produced. Energy source: Historically, the main sources of energy in Chemours manufacturing process for TiO2 were coal and fuel oil, among others. A number of projects have been executed in recent years or are in the pipeline to change energy source from coal to natural gas. Furthermore, Chlorine required for the process at one of the sites is being generated in house, eliminating the environmental footprint associated with transporting toxic chlorine. All these steps have resulted in over 12% reduction in CCP for TiO2 manufacturing in Chemours.
Fig. 3
Contribution of various inputs to the life cycle climate change potential of the TiO2 manufacturing process.
Fig. 4
Climate change potential of select ore used in the TiO2 manufacturing process (EcoInvent Ver. 3, 2013–2015).
360
Applying Life Cycle Assessment (LCA) in Process IndustrydThe Chemours Experience
LCA for Product Comparison Foam expansion agent (FEA) is a substance that produces cellular structures via a foaming process in a variety of materials that undergo hardening or phase transition, most notably in spray polyurethane foams (SPFs) used for insulating homes and appliances. Concern about climate change has created demand for FEAs with low global warming potential (GWP) as well as improved thermal properties. To fully understand the impact of FEA on CCP in SPF applications, a LCA was undertaken by Chemours. While SPFs are used in many applications, this study targeted SPFs in U.S. residential wall applications and took into consideration not only the GWP of the FEA, but also production, installation, and end-of-life greenhouse gas (GHG) emissions, as shown in Fig. 5. Insulation use reduces the energy required to heat or cool a house. Differences in thermal performance of SPFs also result in varying amounts of energy consumption and corresponding GHG emissions associated with the energy production and consumption. The relative GHG burdens from energy use were included in this study. This study compared a spray foam system using OpteonÔ 1100, a zero ODP, low GWP FEA developed by Chemours, to spray foam systems using both historical and currently used FEAs in this application, including HCFC-141b, HFC-245fa, and water/CO2 blown foam. Three climate zones were chosen for this study to show the dependence on both climate and regional influences of energy supply and building practices. Houston, TX, in climate zone 2, Baltimore, MD in climate zone 4, and Chicago, IL in climate zone 5, as defined by American Society of Heating, Refrigerating, and Air-Conditioning Engineers (ASHRAE), were selected as representative of major population centers with significantly different climate impacts. As per ISO 14044, functional unit was defined as the amount of FEA required in one square-meter of installed SPF used in residential wall insulation with a lifetime of 60 years and thickness to fill the wall frame cavity associated with the region of interest. The frame cavity was 3.5 in. for climate zone 2 where all foams studied can achieve the minimum R-13 required in a 200 400 wall frame. For climate zones 4 and 5, 5.5 inches of insulation are used based on a 200 600 wall frame. TRACEÔ Load 700 (by TraneÒ ) was used to model energy savings incurred through usage of the spray foam insulation (American Standard, Inc., 1998). The software uses housing construction data from ASHRAE to assess the energy and economic impacts of building-related parameters such as architectural features, comfort-system design, Heating, ventilation and air conditioning (HVAC) equipment selections, operating schedules, etc. The software provides the heating and cooling load for the building through the year and the yearly average for the three locations considered. Since the goal of this study was to examine the effect of FEA type and usage rate (loading), formulation recipe was gathered for spray foam formulations using HCFC-141b, HFC-245fa, and HFO-1336mzz-Z with varying loading rates as well as for water/CO2 blown foam. Three FEA loading groups are described in this evaluation as “low,” “mid,” and “high,” which correspond to FEA loading of 3–5 wt%, 5–9 wt%, and 9–12 wt% of the total formulation, respectively. Fig. 6 shows net CCP in Chicago, IL for foam insulation with various expansion agents at low, mid, and high loading. Burdens associated with manufacture, installation, use, and end-of-life are shown above the “zero” line in the figures. Credits for energy savings relative to water/CO2 blown foam are shown below the “zero” line. Net CTGr CCP are tabulated in each figure and identified by the dashed blue line across each bar for each FEA installation. For a given FEA loading, all of the halogenated FEA installations provide similar energy savings compared to water/CO2 blown foam. For HFO-1336mzz-Z, these energy savings relative to water/CO2 blown foam are larger than the identified formulation and installation burdens for all FEA loadings. It was further observed through the LCA analysis of other regions (Houston, TX and Baltimore, MD) that the net GHG CTGr emissions for HFO-1336mzz-Z decrease as climatic conditions become colder since the energy savings increase significantly while manufacture and installation burdens increase marginally (due to an increase in wall cavity thickness from 3.500 to 5.500 across the cases evaluated). For HCFC-141b and HFC-245fa, the direct emissions during installation, use, and end-of-life are more significant than the energy savings relative to water/CO2 blown foam. Incremental energy savings relative to water/CO2 blown foam increase with FEA
Fig. 5
System boundaries for the SPF product system.
Applying Life Cycle Assessment (LCA) in Process IndustrydThe Chemours Experience
361
Fig. 6 Cradle-to-Grave climate change potential on an equal thickness basis. Energy savings are normalized to water/CO2 blown foam, that is, results represent incremental differences of energy savings as compared to a water/CO2 blown foam baseline. Energy savings based on Chicago, IL. Net CTGr CCP is tabulated.
loading. However, for high GWP FEA, the benefit gained by increasing FEA loading is largely offset by increases in incremental FEA emissions during product use and end-of-life. While the focus of this study was on CCP, additional metrics and impact categories, including nonrenewable energy use, acidification potential, smog potential, ozone depletion potential, and eutrophication potential were also evaluated. The results for these impact categories are detailed in a third-party-reviewed comparative assessment report (American Standard, Inc., 1998) as per ISO 140040/14044 guidelines and are available upon request. In general, these additional impact categories are not differentiated across the different closed cell foam options as seen for CCP. Chemours have used the findings of this study to highlight the sustainable credentials of its products at various forums including technology and marketing conferences and in customer meetings. Chemours has also extended the study to include the use of OpteonÔ 1100 in other applications, such as in household appliances (Roy et al., 2013). This exercise clearly demonstrates the usefulness of LCA study in industry for effective marketing of their products.
Summary and Conclusion LCA is a powerful tool to evaluate the environmental footprint of processes and products in process industry. DuPont and subsequently Chemours have used LCA in various stages of its product development and have used the findings to improve its processes and advanced the environmental credibility of its products. This article illustrated two such examples in Chemours. An increase in demand for LCA-based Environmental Product Declarations (EPDs) and credits in LEED certification in the US building industry is making LCA indispensable.
References Driving Progress through Sustainability, DuPont Sustainability Report (2015). http://www.dupont.com/corporate-functions/sustainability.html (last accessed on 05/01/2016). EcoInvent Ver. 3, Database for Ilmenite, Rutile and Slag (2013–2015).Opteon™ 1100. GaBi manual. http://www.gabi-software.com/fileadmin/GaBi_Manual/GaBi_6_manual.pdf (last accessed on 05/01/2016). Getting started with TRACE® Load 700. American Standard, Inc. 1998, Version 2.
362
Applying Life Cycle Assessment (LCA) in Process IndustrydThe Chemours Experience
International Organization of Standardization, 2006a. ISO 14040:2006 Environmental management – life cycle assessment – principles and framework. International Organization for Standardization (ISO), Geneva. International Organization of Standardization, 2006b. ISO 14044:2006 Environmental management – life cycle assessment – requirements and guidelines. International Organization for Standardization (ISO), Geneva. PRe training manual. https://www.pre-sustainability.com/lca-methodology (last accessed on 05/01/2016). Roy, S., et al., 2012. Low GWP spray foam expansion agents: why performance also matters. In: Technical conference: Construction 2: advancing the science of SPF for the construction industry. Center for Polyurethane Industries, Atlanta. Roy, S., et al., 2013. Formacel® -1100® : life cycle assessment for use in a household appliance. In: Technical conference: Sustainability: keeping polyurethanes positioned for the future. Center for Polyurethane Industries, Phoenix. Schenck, R., White, P., 2014. Environmental life cycle assessment. In: Published in the United States by American Center for Life Cycle Assessment, Vashon Island, Washington. SimaPro 8 tutorial manual. https://www.pre-sustainability.com/simapro-tutorial (last accessed on 05/01/2016). TDMA Life Cycle Inventory for Titanium Dioxide Production Published in the European Life Cycle Database. http://www.tdma.info/images/Documents/4._TDMA_Life_Cycle_ Inventory_for_Titanium_Dioxide_Production.pdf. The Carbon Footprint of Titanium Dioxide Pigment. http://www.tdma.info/images/Documents/3._TDMA_Carbon_Footprinting.pdf. The greenhouse gas protocol: a corporate accounting and reporting standard. http://www.ghgprotocol.org/files/ghgp/public/ghg-protocol-revised.pdf. Titanium Dioxide Manufacturers Association sustainability, http://www.tdma.info/sustainability (last accessed on 05/01/2016).
Introduction Sustainability has arrived in the mainstream market. Major corporations have set sustainability goals, and have taken steps to meet those goals by improving their processes, products, and supply chains. DuPont, from where Chemours spun off as an independent company in 2015, for example, has published sustainability report for the last 25 years documenting its contribution to environmentally sustainable practices (DuPont Sustainability Report, 2015). During this time its sustainability focus has grown from managing operational footprint to helping its customers lighten their environmental footprint across the value chain. The shift is driven by both governmental and nongovernmental bodies, but also through greater awareness among consumers. Customers are demanding a product that conserves energy and water during manufacturing and use, requires less material to produce and produces minimal waste and have other minimal environmentally detrimental characteristics. Life cycle assessment (LCA) is a tool that provides a holistic quantification of a product’s environmental footprint along the entire supply chain, illustrated in Fig. 1. For systems of interest in process industry, the life cycle steps include extracting raw material from nature, preprocessing and manufacturing, distribution of materials at various stages, use of the product, and its eventual end-of-life through land filling, incineration, or recycling. The methodology and use of LCA has been published extensively in open literature (Schenck and White, 2014; PRe training manual, 2016). In summary ISO 14040/14044 provides the guiding steps for performing LCA (International Organization of Standardization, 2006a,b). Following the ISO guidelines provide LCA practitioners and users consistency in use and interpretation of the analysis originating from various sources and helps in comparing two or more products with similar functions. There are four main steps in LCA as shown in Fig. 2A. In the “Goal and Scope Definition step” the objective of the study as well as the boundary and content of the study is decided. The standard questions such as why, how, what, etc., are discussed in detail. All stakeholders are engaged in the process to arrive at a consensus. The “Inventory Analysis” step is the most involved and time-consuming steps of all. In this step, all relevant inventories of inputs such as material and energy use and the material release to the environment are compiled. For new processes, extensive process modeling is performed to generate the inventory data, whereas for an existing product, the plant data is normally used. In the “Impact Assessment” step, the compiled data is used to calculate potential environmental impacts. The conversion of inventory data to impact assessment can be accomplished in spreadsheet, but most often canned software (SimaPro 8 tutorial manual, 2016; GaBi manual, 2016.) are used to handle the large amount of data involved. A sample list of impact assessments is shown in Fig. 2B. The midpoint impact category is a problem-oriented approach that translates impacts into environmental themes such as climate change, acidification, human toxicity, etc. Using appropriate weighing factors, the midpoint impact assessments can be converted into endpoint impact category, also known as the damage-oriented approach. Endpoint translates environmental impacts into issues of concern such as human health, natural environment, and natural resources. LCA, as a tool to quantify environmental impacts, has wide applicability in industry. Corporations use LCA to develop sustainable business strategies by identifying direct and indirect emissions, as outlined by The Greenhouse Gas Protocol (The Greenhouse Gas Protocol, n.d.) for corporations. Based on LCA, the most environmentally friendly raw materials and utilities can be identified,
Fig. 1
Life cycle stages of a product.
Encyclopedia of Sustainable Technologies, Volume 1
http://dx.doi.org/10.1016/B978-0-12-409548-9.10073-9
357
358
Fig. 2
Applying Life Cycle Assessment (LCA) in Process IndustrydThe Chemours Experience
(A) The phases of life cycle assessment study. (B) Sample list of impact assessments.
and the best end-of-life process can be executed. LCA is also used, in addition to economics, to decide the best process to convert an idea to a product by selecting a technology that optimizes the environmental and economic gains. LCA has also proven to be a great marketing tool where manufacturers highlight competitive edge in markets where customers demand more environmentally friendly products.
The Chemours Initiatives Chemours as well as its mother company DuPont have extensively used LCA for most of the hundreds of new products it launches each year. LCA has been used to develop new application of Chemours’ products in building and construction (Roy et al., 2012), food and beverage storage (internal memo, work in progress), household appliances (Roy et al., 2013), and many others. LCA has also been used to improve the operations within the company fence line, explore alternate raw material as well as to improve the supply chain for materials and energy for an overall reduction in environmental footprint. By demonstrating sustainability through LCA, Chemours has extensively used LCA reports for product differentiation and marketing in technical and industrial forums. In this article, two such examples will be discussed with an aim to encourage readers to incorporate life cycle thinking in their normal work stream.
Process Improvement Through LCA: Titanium Dioxide Chemours is a leading manufacturer of titanium dioxide (TiO2), a whitening pigment used in paints, plastics, laminates, and papers. Chemours manufactures TiO2 using chloride process to convert Ti bearing ore into various grades of TiO2. Significant amounts of chemicals and energy are required in the manufacturing process. Therefore, TiO2 manufacturers have been especially mindful of its environmental footprint, and have strived to achieve high sustainability in their processes (Titanium Dioxide Manufacturers Association, 2016). Responding to customer requests for environmental footprint data, the Titanium Dioxide Manufacturers Association (TDMA) developed a rigorous titanium dioxide product footprint accounting and reporting method and published representative average
Applying Life Cycle Assessment (LCA) in Process IndustrydThe Chemours Experience
359
data for the 2010 and 2012 cradle-to-gate carbon footprint of titanium dioxide manufacture (The Carbon Footprint of Titanium Dioxide Pigment, n.d.). In 2014, TDMA expanded this footprinting method to compile a robust and representative cradle-togate life cycle inventory (LCI) of titanium dioxide manufacture in 2012. The LCI data set was externally reviewed and is now freely available in the European Life Cycle Data Base ELCD (TDMA Life Cycle, n.d.). The inventory data is representative of 33 TiO2 manufacturing sites from 9 companies including Chemours, covering more than 50% of the world production. Carbon footprint was the primary impact assessment evaluated, however, other impacts were also studied. Chemours is an associate member of TDMA. Chemours has extensively contributed to the development of the industry LCI data by providing representative data from its TiO2 manufacturing sites. The impact assessment published by TDMA is representative of the environmental footprint of Chemours TiO2 manufacturing process. The industry average cycle climate change potential (CCP) is 5.78 kg CO2/kg TiO2. The distribution of various inputs to the TiO2 manufacturing process to the life cycle CCP is shown in Fig. 3. It is clear from the above figure that the ore, energy, and site emissions related to the use of energy, as well as the chemicals used at various places in the manufacturing process contribute significantly to the overall CCP. In the last few years, Chemours has undertaken a number of projects to manage its process steps and supply chains to reduce its CCP and the overall industry footprint. Some of the steps include: Titanium ore type: Beneficiated ores such as slag and synthetic rutile has a high CCP compared to mined rutile, as shown in Fig. 4. Chemours has undertaken steps to reduce the usage of beneficiated ores. On a life cycle basis, this has resulted in an average decrease in CCP per kg of TiO2 produced. Energy source: Historically, the main sources of energy in Chemours manufacturing process for TiO2 were coal and fuel oil, among others. A number of projects have been executed in recent years or are in the pipeline to change energy source from coal to natural gas. Furthermore, Chlorine required for the process at one of the sites is being generated in house, eliminating the environmental footprint associated with transporting toxic chlorine. All these steps have resulted in over 12% reduction in CCP for TiO2 manufacturing in Chemours.
Fig. 3
Contribution of various inputs to the life cycle climate change potential of the TiO2 manufacturing process.
Fig. 4
Climate change potential of select ore used in the TiO2 manufacturing process (EcoInvent Ver. 3, 2013–2015).
360
Applying Life Cycle Assessment (LCA) in Process IndustrydThe Chemours Experience
LCA for Product Comparison Foam expansion agent (FEA) is a substance that produces cellular structures via a foaming process in a variety of materials that undergo hardening or phase transition, most notably in spray polyurethane foams (SPFs) used for insulating homes and appliances. Concern about climate change has created demand for FEAs with low global warming potential (GWP) as well as improved thermal properties. To fully understand the impact of FEA on CCP in SPF applications, a LCA was undertaken by Chemours. While SPFs are used in many applications, this study targeted SPFs in U.S. residential wall applications and took into consideration not only the GWP of the FEA, but also production, installation, and end-of-life greenhouse gas (GHG) emissions, as shown in Fig. 5. Insulation use reduces the energy required to heat or cool a house. Differences in thermal performance of SPFs also result in varying amounts of energy consumption and corresponding GHG emissions associated with the energy production and consumption. The relative GHG burdens from energy use were included in this study. This study compared a spray foam system using OpteonÔ 1100, a zero ODP, low GWP FEA developed by Chemours, to spray foam systems using both historical and currently used FEAs in this application, including HCFC-141b, HFC-245fa, and water/CO2 blown foam. Three climate zones were chosen for this study to show the dependence on both climate and regional influences of energy supply and building practices. Houston, TX, in climate zone 2, Baltimore, MD in climate zone 4, and Chicago, IL in climate zone 5, as defined by American Society of Heating, Refrigerating, and Air-Conditioning Engineers (ASHRAE), were selected as representative of major population centers with significantly different climate impacts. As per ISO 14044, functional unit was defined as the amount of FEA required in one square-meter of installed SPF used in residential wall insulation with a lifetime of 60 years and thickness to fill the wall frame cavity associated with the region of interest. The frame cavity was 3.5 in. for climate zone 2 where all foams studied can achieve the minimum R-13 required in a 200 400 wall frame. For climate zones 4 and 5, 5.5 inches of insulation are used based on a 200 600 wall frame. TRACEÔ Load 700 (by TraneÒ ) was used to model energy savings incurred through usage of the spray foam insulation (American Standard, Inc., 1998). The software uses housing construction data from ASHRAE to assess the energy and economic impacts of building-related parameters such as architectural features, comfort-system design, Heating, ventilation and air conditioning (HVAC) equipment selections, operating schedules, etc. The software provides the heating and cooling load for the building through the year and the yearly average for the three locations considered. Since the goal of this study was to examine the effect of FEA type and usage rate (loading), formulation recipe was gathered for spray foam formulations using HCFC-141b, HFC-245fa, and HFO-1336mzz-Z with varying loading rates as well as for water/CO2 blown foam. Three FEA loading groups are described in this evaluation as “low,” “mid,” and “high,” which correspond to FEA loading of 3–5 wt%, 5–9 wt%, and 9–12 wt% of the total formulation, respectively. Fig. 6 shows net CCP in Chicago, IL for foam insulation with various expansion agents at low, mid, and high loading. Burdens associated with manufacture, installation, use, and end-of-life are shown above the “zero” line in the figures. Credits for energy savings relative to water/CO2 blown foam are shown below the “zero” line. Net CTGr CCP are tabulated in each figure and identified by the dashed blue line across each bar for each FEA installation. For a given FEA loading, all of the halogenated FEA installations provide similar energy savings compared to water/CO2 blown foam. For HFO-1336mzz-Z, these energy savings relative to water/CO2 blown foam are larger than the identified formulation and installation burdens for all FEA loadings. It was further observed through the LCA analysis of other regions (Houston, TX and Baltimore, MD) that the net GHG CTGr emissions for HFO-1336mzz-Z decrease as climatic conditions become colder since the energy savings increase significantly while manufacture and installation burdens increase marginally (due to an increase in wall cavity thickness from 3.500 to 5.500 across the cases evaluated). For HCFC-141b and HFC-245fa, the direct emissions during installation, use, and end-of-life are more significant than the energy savings relative to water/CO2 blown foam. Incremental energy savings relative to water/CO2 blown foam increase with FEA
Fig. 5
System boundaries for the SPF product system.
Applying Life Cycle Assessment (LCA) in Process IndustrydThe Chemours Experience
361
Fig. 6 Cradle-to-Grave climate change potential on an equal thickness basis. Energy savings are normalized to water/CO2 blown foam, that is, results represent incremental differences of energy savings as compared to a water/CO2 blown foam baseline. Energy savings based on Chicago, IL. Net CTGr CCP is tabulated.
loading. However, for high GWP FEA, the benefit gained by increasing FEA loading is largely offset by increases in incremental FEA emissions during product use and end-of-life. While the focus of this study was on CCP, additional metrics and impact categories, including nonrenewable energy use, acidification potential, smog potential, ozone depletion potential, and eutrophication potential were also evaluated. The results for these impact categories are detailed in a third-party-reviewed comparative assessment report (American Standard, Inc., 1998) as per ISO 140040/14044 guidelines and are available upon request. In general, these additional impact categories are not differentiated across the different closed cell foam options as seen for CCP. Chemours have used the findings of this study to highlight the sustainable credentials of its products at various forums including technology and marketing conferences and in customer meetings. Chemours has also extended the study to include the use of OpteonÔ 1100 in other applications, such as in household appliances (Roy et al., 2013). This exercise clearly demonstrates the usefulness of LCA study in industry for effective marketing of their products.
Summary and Conclusion LCA is a powerful tool to evaluate the environmental footprint of processes and products in process industry. DuPont and subsequently Chemours have used LCA in various stages of its product development and have used the findings to improve its processes and advanced the environmental credibility of its products. This article illustrated two such examples in Chemours. An increase in demand for LCA-based Environmental Product Declarations (EPDs) and credits in LEED certification in the US building industry is making LCA indispensable.
References Driving Progress through Sustainability, DuPont Sustainability Report (2015). http://www.dupont.com/corporate-functions/sustainability.html (last accessed on 05/01/2016). EcoInvent Ver. 3, Database for Ilmenite, Rutile and Slag (2013–2015).Opteon™ 1100. GaBi manual. http://www.gabi-software.com/fileadmin/GaBi_Manual/GaBi_6_manual.pdf (last accessed on 05/01/2016). Getting started with TRACE® Load 700. American Standard, Inc. 1998, Version 2.
362
Applying Life Cycle Assessment (LCA) in Process IndustrydThe Chemours Experience
International Organization of Standardization, 2006a. ISO 14040:2006 Environmental management – life cycle assessment – principles and framework. International Organization for Standardization (ISO), Geneva. International Organization of Standardization, 2006b. ISO 14044:2006 Environmental management – life cycle assessment – requirements and guidelines. International Organization for Standardization (ISO), Geneva. PRe training manual. https://www.pre-sustainability.com/lca-methodology (last accessed on 05/01/2016). Roy, S., et al., 2012. Low GWP spray foam expansion agents: why performance also matters. In: Technical conference: Construction 2: advancing the science of SPF for the construction industry. Center for Polyurethane Industries, Atlanta. Roy, S., et al., 2013. Formacel® -1100® : life cycle assessment for use in a household appliance. In: Technical conference: Sustainability: keeping polyurethanes positioned for the future. Center for Polyurethane Industries, Phoenix. Schenck, R., White, P., 2014. Environmental life cycle assessment. In: Published in the United States by American Center for Life Cycle Assessment, Vashon Island, Washington. SimaPro 8 tutorial manual. https://www.pre-sustainability.com/simapro-tutorial (last accessed on 05/01/2016). TDMA Life Cycle Inventory for Titanium Dioxide Production Published in the European Life Cycle Database. http://www.tdma.info/images/Documents/4._TDMA_Life_Cycle_ Inventory_for_Titanium_Dioxide_Production.pdf. The Carbon Footprint of Titanium Dioxide Pigment. http://www.tdma.info/images/Documents/3._TDMA_Carbon_Footprinting.pdf. The greenhouse gas protocol: a corporate accounting and reporting standard. http://www.ghgprotocol.org/files/ghgp/public/ghg-protocol-revised.pdf. Titanium Dioxide Manufacturers Association sustainability, http://www.tdma.info/sustainability (last accessed on 05/01/2016).