Matching Items (2)
Description
Fossil resources have enabled the development of the plastic industry in the last century. More recently biopolymers have been making gains in the global plastics market. Biopolymers are plastics derived from plants, primarily corn, which can function very similarly to fossil based plastics. One difference between some of the dominant biopolymers, namely polylactic acid and thermoplastic starch, and the most common fossil-based plastics is the feature of compostability. This means that biopolymers represent not only a shift from petroleum and natural gas to agricultural resources but also that these plastics have potentially different impacts resulting from alternative disposal routes. The current end of life material flows are not well understood since waste streams vary widely based on regional availability of end of life treatments and the role that decision making has on waste identification and disposal.
This dissertation is focused on highlighting the importance of end of life on the life-cycle of biopolymers, identifying how compostable biopolymer products are entering waste streams, improving collection and waste processing, and quantifying the impacts that result from the disposal of biopolymers. Biopolymers, while somewhat available to residential consumers, are primarily being used by various food service organizations trying to achieve a variety of goals such as zero waste, green advertising, and providing more consumer options. While compostable biopolymers may be able to help reduce wastes to landfill they do result in environmental tradeoffs associated with agriculture during the production phase. Biopolymers may improve the management for compostable waste streams by enabling streamlined services and reducing non-compostable fossil-based plastic contamination. The concerns about incomplete degradation of biopolymers in composting facilities may be ameliorated using alkaline amendments sourced from waste streams of other industries. While recycling still yields major benefits for traditional resins, bio-based equivalents may provide addition benefits and compostable biopolymers offer benefits with regards to global warming and fossil fuel depletion. The research presented here represents two published studies, two studies which have been accepted for publication, and a life-cycle assessment that will be submitted for publication.
This dissertation is focused on highlighting the importance of end of life on the life-cycle of biopolymers, identifying how compostable biopolymer products are entering waste streams, improving collection and waste processing, and quantifying the impacts that result from the disposal of biopolymers. Biopolymers, while somewhat available to residential consumers, are primarily being used by various food service organizations trying to achieve a variety of goals such as zero waste, green advertising, and providing more consumer options. While compostable biopolymers may be able to help reduce wastes to landfill they do result in environmental tradeoffs associated with agriculture during the production phase. Biopolymers may improve the management for compostable waste streams by enabling streamlined services and reducing non-compostable fossil-based plastic contamination. The concerns about incomplete degradation of biopolymers in composting facilities may be ameliorated using alkaline amendments sourced from waste streams of other industries. While recycling still yields major benefits for traditional resins, bio-based equivalents may provide addition benefits and compostable biopolymers offer benefits with regards to global warming and fossil fuel depletion. The research presented here represents two published studies, two studies which have been accepted for publication, and a life-cycle assessment that will be submitted for publication.
ContributorsHottle, Troy A (Author) / Landis, Amy E. (Thesis advisor) / Allenby, Braden R. (Thesis advisor) / Bilec, Melissa M (Committee member) / Arizona State University (Publisher)
Created2015
Description
The proliferation of plastic has created a wicked global sustainability challenge. From the extraction of fossil fuels to end-of-life management and pollution, plastic imposes significant negative impacts to human health, economic well-being, and the environment. One proposed solution is to replace conventional plastic with biomass-based plastics and plastic alternatives (BBPAs), such as paper or bio-based plastics. While these products may have advantageous properties, they require biomass as a feedstock. Given the scale of the plastics problem, this biomass demand may be significant. In my dissertation, I evaluate the magnitude of biomass required, and assess the potential impact of this biomass demand on global land use. After examining the scope and the scale of the problem in chapter one, I evaluate the assumptions that have been made regarding the land-use impacts of BBPAs in chapter two. In chapter three, I use a global land-system model (CLUMondo) to evaluate the potential land-use change of large-scale production of BBPAs. In chapter four, I evaluate how certification schemes could be used as a policy tool to mitigate the land-use impacts of bio-based alternatives. I find that the current studies evaluating the land-use impacts of these products make optimistic and unrealistic assumptions regarding land-use. Using a global model, I show how high production scenarios of BBPAs could induce significant land-use change at the global level. Finally, I demonstrate that reliance on certification schemes would likely be insufficient to prevent negative impacts from this scale of land change. Overall, this dissertation suggests that large-scale replacement of plastic with BBPAs could incur significant land-use impacts. Policies designed to mitigate the impacts of plastic need to account for this impact to land-use, lest they risk substituting one global problem for another.
ContributorsHelm, Levi (Author) / Kinzig, Ann (Thesis advisor) / Dooley, Kevin (Committee member) / Turner II, Billie (Committee member) / Verburg, Peter (Committee member) / Arizona State University (Publisher)
Created2023