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Different Roads to the Same Destination?

Description

Sustainable Materials Management and Circular Economy are both frameworks for considering the way we interact with the world's resources. Different organizations and institutions across the world have adopted one philosophy or the other. To some, there seems to be little

Sustainable Materials Management and Circular Economy are both frameworks for considering the way we interact with the world's resources. Different organizations and institutions across the world have adopted one philosophy or the other. To some, there seems to be little overlap of the two, and to others, they are perceived as being interchangeable. This paper evaluates Sustainable Materials Management (SMM) and Circular Economy (CE) individually and in comparison to see how truly different these frameworks are from one another. This comparison is then extended into a theoretical walk-through of an SMM treatment of concrete pavement in contrast with a CE treatment. With concrete being a ubiquitous in the world's buildings and roads, as well as being a major constituent of Construction & Demolition waste generated, its analysis is applicable to a significant portion of the world's material flow. The ultimate test of differentiation between SMM and CE would ask: 1) If SMM principles guided action, would the outcomes be aligned with or at odds with CE principles? and conversely 2) If CE principles guided action, would the outcomes be aligned with or at odds with SMM principles? Using concrete pavement as an example, this paper seeks to determine whether or not Sustainable Materials Management and Circular Economy are simply different roads leading to the same destination.

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Date Created
2017-05

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Beyond recycling: design for disassembly, reuse, and circular economy in the built environment

Description

Today, we use resources faster than they can be replaced. Construction consumes more resources than any other industry and has one of the largest waste streams. Resource consumption and waste generation are expected to grow as the global population increases.

Today, we use resources faster than they can be replaced. Construction consumes more resources than any other industry and has one of the largest waste streams. Resource consumption and waste generation are expected to grow as the global population increases. The circular economy (CE) is based on the concept of a closed-loop cycle (CLC) and proposes a solution that, in theory, can eliminate the environmental impacts caused by construction and demolition (C&D) waste and increase the efficiency of resources’ use. In a CLC, building materials are reused, remanufactured, recycled, and reintegrated into other buildings (or into other sectors) without creating any waste.

Designing out waste is the core principle of the CE. Design for disassembly or design for deconstruction (DfD) is the practice of planning the future deconstruction of a building and the reuse of its materials. Concepts like DfD, CE, and product-service systems (PSS) can work together to promote CLC in the built environment. PSS are business models based on stewardship instead of ownership. CE combines DfD, PSS, materials’ durability, and materials’ reuse in multiple life cycles to promote a low-carbon, regenerative economy. CE prioritizes reuse over recycling. Dealing with resource scarcity demands us to think beyond the incremental changes from recycling waste; it demands an urgent, systemic, and radical change in the way we design, build, and procure construction materials.

This dissertation aims to answer three research questions: 1) How can researchers estimate the environmental benefits of reusing building components, 2) What variables are susceptible to affect the environmental impact assessment of reuse, and 3) What are the barriers and opportunities for DfD and materials’ reuse in the current design practice in the United States.

The first part of this study investigated how different life cycle assessment (LCA) methods (i.e., hybrid LCA and process-based LCA), assumptions (e.g., reuse rates, transportation distances, number of reuses), and LCA timelines can affect the results of a closed-loop LCA. The second part of this study built on interviews with architects in the United States to understand why DfD is not part of the current design practice in the country.

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Date Created
2018

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Quantifying the Impact of Circular Economy Applied to the Built Environment: A Study of Construction and Demolition Waste to Identify Leverage Points

Description

The built environment is responsible for a significant portion of global waste generation.

Construction and demolition (C&D) waste requires significant landfill areas and costs

billions of dollars. New business models that reduce this waste may prove to be financially

beneficial and generally more

The built environment is responsible for a significant portion of global waste generation.

Construction and demolition (C&D) waste requires significant landfill areas and costs

billions of dollars. New business models that reduce this waste may prove to be financially

beneficial and generally more sustainable. One such model is referred to as the “Circular

Economy” (CE), which promotes the efficient use of materials to minimize waste

generation and raw material consumption. CE is achieved by maximizing the life of

materials and components and by reclaiming the typically wasted value at the end of their

life. This thesis identifies the potential opportunities for using CE in the built environment.

It first calculates the magnitude of C&D waste and its main streams, highlights the top

C&D materials based on weight and value using data from various regions, identifies the

top C&D materials’ current recycling and reuse rates, and finally estimates a potential

financial benefit of $3.7 billion from redirecting C&D waste using the CE concept in the

United States.

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Agent

Created

Date Created
2019

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Role of Circular Economy in the Indigenous Built Environment: An Assessment of Design and Construction Potential of Circular Building Materials in an American Indian Community

Description

This thesis intends to help inform American Indian nations’ decision making related to housing. The study recognizes the urgent need for housing solutions that fit the needs of a community as well as benefit the overall ecosystem. One model that

This thesis intends to help inform American Indian nations’ decision making related to housing. The study recognizes the urgent need for housing solutions that fit the needs of a community as well as benefit the overall ecosystem. One model that can offer guidance is the Circular Economy (CE) model. A well-thought-out CE process can provide housing solutions that are economically, socially, and environmentally sustainable. It also stimulates the local economy by strategically introducing positive changes. This research identifies the construction potential of available circular materials as compared to more contemporary building materials. It then recommends a closed-loop circular model that utilizes the community’s existing infrastructure to develop affordable housing. The proposed CE model operates within the built environment, stimulating local employment while catering to the needs of the residents. Such an approach can prove to be beneficial for the local community and perhaps scalable to the global economy.

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Agent

Created

Date Created
2020

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Addressing the Limitations of Life Cycle Assessments for Circular Economy Packaging Innovations with the Kaiteki Innovation Framework

Description

ABSTRACT

Historically, Life Cycle Assessments (LCA) guided companies to make better decisions to improve the environmental impacts of their products. However, as new Circular Economy (CE) tools emerge, the usefulness of LCA in assessing linear products grow more and more obsolete.

ABSTRACT

Historically, Life Cycle Assessments (LCA) guided companies to make better decisions to improve the environmental impacts of their products. However, as new Circular Economy (CE) tools emerge, the usefulness of LCA in assessing linear products grow more and more obsolete. Research Question: How do LCA-based tools account for reuse/multiple life cycles of products verses CE-based tools?

The Kaiteki Innovation Framework (KIF) was used to address the question of circularity of two packaging materials using an Environmental LCA to populate its 12 CE dimensions. Any gaps were evaluated with 2 LCA- based and 2 CE-based tools to see which could address the leftover CE dimensions.

Results showed that to complete the KIF template, LCA data required one of the LCA-based tools: Social Life Cycle Assessment (SLCA) and both CE-based tools: Circular Transition Indicators (CTI) and Material Circularity Indicator (MCI) to supplement gaps in the KIF. The LCA addressed 5 of the KIF dimensions: Innovation Category Name, Description, GHG Impact, Other Environmental Impacts, and Value Chain Position. 3 analytical tools addressed 5 more:: Effect on Circularity, Social Impacts, Enabling Technologies, Tier 2 and 3 Requirements, and Value Chain Synergies. None of the tools could address the KIF Dimensions: State of Development or Scale Requirements. All in all, the KIF required both LCA-based and CE-based tools to cover social and socio-economic impacts from a cradle-to-cradle perspective with multiple circular loops in mind. These results can help in the research and development of innovative, circular products that can lead to a more environmentally preferred future.

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Agent

Created

Date Created
2020

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Conversations with the Circular Consumer

Description

The circular economy is viewed as a solution to many of the environmental and social ills that the linear economy has exacerbated. Whether it is through refill solutions or redesigning a cardboard shipping container, fast-moving consumer goods (FMCG) brands are

The circular economy is viewed as a solution to many of the environmental and social ills that the linear economy has exacerbated. Whether it is through refill solutions or redesigning a cardboard shipping container, fast-moving consumer goods (FMCG) brands are rethinking the way their products are delivered to consumers through business model innovations that promote circularity. The consumer plays the important, often overlooked, role of enabler within circular business models. This study aims to increase broader understanding of what motivates circular consumption of fast-moving consumer goods while analyzing the relationship between motivators and the behaviors required to participate. Semi-structured interviews provide insights from consumers who are currently purchasing household cleansers from brands that operate with a circular business model. Results from this study highlight a group of consumers that are distinguished by their common desire to reduce their personal consumption of plastics. There is clear indication that these consumers are in fact seeking out ways to consume more sustainably. A significant subset of this group expresses concern regarding ingredients used in the products. Health concerns for themselves, their family, or a pet are driving a desire to understand product ingredients. There is evidence to indicate that the concern for personal consumption of plastics is being driven by information distributed via social media and supported by targeted advertisements for brands that address this concern.

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Agent

Created

Date Created
2020

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Using Industry Data to Make an Impact on Construction Practices over the Project Lifecycle

Description

The construction industry generates tremendous amounts of data every day. Data can inform practitioners to increase their project performance as well as the quality of the resulting built environment. The data gathered from each stage has unique characteristics, and processing

The construction industry generates tremendous amounts of data every day. Data can inform practitioners to increase their project performance as well as the quality of the resulting built environment. The data gathered from each stage has unique characteristics, and processing them to the appropriate information is critical. However, it is often difficult to measure the impact of the research across project phases (i.e., planning, design, construction, operation and maintenance, and end-of-life). The goal of this dissertation is to present how industry data can be used to make an impact on construction practices and test a suite of methods to measure the impact of construction research across project phases. The dissertation provides examples of impactful research studies for each project phase to demonstrate the collection and utilization of data generated from each stage and to assess the potential tangible impact on construction industry practices. The completed studies presented both quantitative and qualitative analyses. The first study focuses on the planning phase and provides a practice to improve frond end planning (FEP) implementation by developing the project definition rating index (PDRI) maturity and accuracy total rating system (MATRS). The second study uses earned value management system (EVMS) information from the design and construction phases to support reliable project control and management. The dissertation then provides a third study, this time focusing on the operations phase and comparing the impact of project delivery methods using the international roughness index (IRI). Lastly, the end-of-life or decommissioning phase is tackled through a study that gauges the monetary impact of the circular economy concept applied to reuse construction and demolition (C&D) waste. This dissertation measures the impact of the research according to the knowledge mobilization (KMb) theory, which illustrates the value of the work to the public and to practitioners.

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Created

Date Created
2020

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Production of Renewable Fuels from Bio-Based Feedstocks: A Viable Path to Enhance Value Chain and Sustainability

Description

The continued reliance on fossil fuel for energy resources has proven to be unsustainable, leading to depletion of world reserves and emission of greenhouse gases during their combustion. Therefore, research initiatives to develop potentially carbon-neutral biofuels were given the highest

The continued reliance on fossil fuel for energy resources has proven to be unsustainable, leading to depletion of world reserves and emission of greenhouse gases during their combustion. Therefore, research initiatives to develop potentially carbon-neutral biofuels were given the highest importance. Hydrothermal liquefaction (HTL, a thermochemical conversion process) of microalgae is recognized as a favorable and efficient technique to produce liquid biofuels from wet feedstocks. In this work, three different microalgae (Kirchneriella sp., Galdieria sulphuraria, Micractinium sp.) grown and harvested at Arizona State University were hydrothermally liquefied to optimize their process conditions under different temperatures (200-375 °C), residence times (15-60 min), solids loadings (10-20 wt.%), and process pressures (9-24 MPa). A one-factor-at-a-time approach was employed, and comprehensive experiments were conducted at 10 % solid loadings and a residence time of 30 min. Co-liquefaction of Salicornia bigelovii Torr. (SL), Swine manure (SM) with Cyanidioschyzon merolae (CM) was tested for the presence of synergy. A positive synergistic effect was observed during the co-liquefaction of biomasses, where the experimental yield (32.95 wt.%) of biocrude oil was higher than the expected value (29.23 wt.% ). Co-liquefaction also led to an increase in the energy content of the co-liquefied biocrude oil and a higher energy recovery rate ( 88.55 %). The HTL biocrude was measured for energy content, elemental, and chemical composition using GC-MS. HTL aqueous phase was analyzed for potential co-products by spectrophotometric techniques and is rich in soluble carbohydrates, dissolved ammoniacal nitrogen, and phosphates. HTL biochar was studied for its nutrient content (nitrogen and phosphorous) and viability of its recovery to cultivate algae without any inhibition using the nutrient leaching. HTL biochar was also studied to produce hydrogen via pyrolysis using a membrane reactor at 500 °C, 1 atm, for 24 h to produce 5.93 wt.% gas. The gaseous product contains 45.7 mol % H2, 44.05 ml % CH4, and 10.25 mol % of CO. The versatile applications of HTL biochar were proposed from a detailed physicochemical characterization. The metal impurities in the algae, bio-oil, and biochar were quantified by ICP-OES where algae and biochar contain a large proportion of phosphorous and magnesium.

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Date Created
2020

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Three Essays on Implementing a Sustainable Circular Economy for Plastics

Description

Plastic is a valuable part of the consumer economy, but it creates negative environmental externalities throughout its lifecycle. To reduce these effects, a sustainable circular economy is needed, where more plastic is diverted from landfill or environmental sinks through reduction,

Plastic is a valuable part of the consumer economy, but it creates negative environmental externalities throughout its lifecycle. To reduce these effects, a sustainable circular economy is needed, where more plastic is diverted from landfill or environmental sinks through reduction, reuse, recycling, or composting, while addressing social needs. Although many different stakeholders (industry, academia, policymakers) are calling for a sustainable circular economy for plastics, globally, less than 20% of plastic is recycled with no data on reduction and reuse. In this dissertation, a mixed methods approach is used to suggest how organizations related to the plastic industry can implement a sustainable circular economy. The first chapter identifies how firms across the plastic value chain can innovate to adopt a sustainable circular flow. A systematic review reveals over 300 examples, which are used to create a material flow typology. Findings summarize five critical points of innovation and indicate that innovation adoption is low. More concerted efforts are needed to improve innovation adoption and there is a need to shift innovation focus from resource efficiency to sustainability. The second chapters studies U.S. plastic recyclers’ price signals to generate evidence for favorable recycling policies. A hedonic analysis reveals recyclers preferences for recyclability – plastic properties that enable recycling. Results suggest that adequate recycling infrastructure and absence of virgin plastic can play an important role in facilitating more recycling. In the third paper, the role of governments as consumers is studied. As the largest consumers in a market, governments can signal a large demand for circular products and services, however public administration literature has paid limited attention to it. A theoretical framework is created to fill the knowledge gap and suggest how governments can use sustainable public procurement for a circular economy. A systematic literature review of the top ten public administration journals over 32 years reveals critical knowledge gaps and the potential for important sustainable public procurement research

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Date Created
2022