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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
161

Food Waste Treatment Options at the University of Cincinnati: Life Cycle Assessment and Economic Evaluation

Zhu, Chao 27 October 2014 (has links)
No description available.
162

Comparison of Solid-State to Liquid Phase Anaerobic Digestion of Lignocellulosic Biomass for Biogas Production

Brown, Dan Lee 14 August 2012 (has links)
No description available.
163

Förpackningar till frukt ochgrönsaker i relation till matsvinn : En studie om förpackningar till frukt och grönsaker kan motiveras ur klimatsynpunkt / Fruit and vegetables packaging in relation to food waste : A study about plastic packaging for fruit and vegetables can be justified from a climate point of view

Précenth, Josefine January 2022 (has links)
En tredjedel av den globala producerade maten gick förlorad 2019 samtidigt som 690 miljoner människor gick hungriga. Maten som inte konsumeras står för 8–10% av de globala växthusgaserna. I Sverige står livsmedelsbutiker och hushållen för en stor del av matsvinnet, där det slängdes 70 000 ton från livsmedelsbutiker och grossister. För att minska matsvinnet och skydda livsmedel används förpackningar, där en huvudfunktion är att skydda maten och förlänga dess hållbarhet. Även om plastförpackningar gör klimatmässig nytta om mindre mängd mat slängs orsakar den stora problem om den inte återvinns utan hamnar i naturen och till slut i haven. Det är då viktigt att räkna på om mängden plast kan motiveras ur klimatsynpunkt för att den skyddar produkten och minskar svinnet. Syftet med studien var att undersöka om och för vilka frukt och grönsaker som plastförpackningar kan motiveras ur klimatsynpunkt om en minskning av svinn sker. Där målet med studien var att besvara för vilka frukt och grönsakers förpackningar kan motiveras utifrån om det sker en reduktion av svinn i butik och hushåll. För att kunna undersöka frågan togs frukt och grönsakernas klimatpåverkan fram samt förpackningarnas klimatpåverkan. Med hjälp av tidigare livscykelanalysstudier och SimaPro kunde data erhållas. Förpackningars material och mängd erhölls från Sydgrönt och Pacsystem samt från egen framtagen data från inköpta frukt och grönsaker. De frukt och grönsaker som undersöktes var morötter, plommontomat, snackstomat, paprika, äpple, avokado, päron, champinjoner, kiwi, broccoli, isbergssallat och bladsallad. Resultaten visade att bladsallad, avokado och plommontomat som odlas i växthus med stor sannolikhet kan motiveras för användning av förpackning med hänsyn till butik- och hushållssvinn. De frukt och grönsaker som osannolikt kan motiveras för användning av förpackning är frilandsodlade snackstomater, päron och champinjoner. Dessa livsmedel behöver en minskning av svinn i både hushåll och butik på över 28% vilket är en osäkerhet om det går att uppnå sådana minskningar av svinn. Orsaken till att de sannolikt inte kan motiveras är på grund av deras låga klimatpåverkan i relation till mängd förpackning och dess klimatpåverkan. Förpackningar med lägre klimatpåverkan som till exempel kartong bör användas för att förpackningar ska kunna motiveras på de frukt och grönsaker som är ömtåliga. / One third of the globally produced food was wasted in 2019 while 690 million people went hungry. Food that is not consumed accounts for 8-10% of global greenhouse gases. In Sweden, grocery stores and households account for a large part of food waste, where 70,000 tonnes were thrown away from grocery stores and wholesalers. To reduce food waste packaging is used, where a main function is to protect the food and extend its shelf life. Although the environment can benefit from plastic packaging if only small amount of food is discarded, it causes major problems if it is not recycled and ends up in nature and eventually in the oceans. It is then important to calculate whether the amount of plastic can be justified from a climate point of view because it protects the product and reduces waste. The purpose of the study was to investigate whether and for which fruits and vegetables plastic packaging can be justified from a climate point of view if a reduction in wastage occurs. Where the aim of the study was to answer for which fruit and vegetable packaging can be justified based on whether there is a reduction in waste in grocery stores and households. To investigate the issue, the climate impact of fruit and vegetables and the climate impact of packaging were developed. With the help of already existing life cycle analysis studies and SimaPro, data could be obtained. The material and quantity of packaging was obtained from Sydgrönt and Pacsystem, as well as from own data produced from purchased fruit and vegetables. The fruits and vegetables examined were carrots, plum tomatoes, snack tomatoes, peppers, apples, avocados, pears, mushrooms, kiwi, broccoli, iceberg lettuce and lettuce. The results showed that leaf lettuce, avocado and plum tomatoes grown in greenhouses can with high probability be justified for the use of packaging regarding store and household waste. The fruits and vegetables that are unlikely to be justified for the use of packaging are free-range snack tomatoes, pears and mushrooms. These foods need a reduction in waste in both households and shops of over 28%, which is an uncertainty as to whether such reductions in waste can be achieved. The reason why they can probably not be justified is due to their low climate impact in relation to the amount of packaging and its climate impact. Packages with a lower climate impact, such as cardboard, should be used to justify packaging on the fruits and vegetables that are fragile.
164

Livscykelanalys av avfallsförbränning och biogasproduktion

Lysell, Sara January 2014 (has links)
Livscykelanalys används som metod för att undersöka produkter eller tjänster från ”vaggan tillgraven”. Med hjälp av mjukvaruprogrammet SimaPro utförs en livscykelanalys på förbränning av avfall med energiutvinning. Resultatet jämförs med en livscykelanalys som utförs på biogasproduktion från matavfall, för att visa vilken av processerna som har mer positiv påverkan på miljön. Resultatet visar att förbränning av avfall bidrar till minskad miljöpåverkan med 63,9 kg CO2-ekvivalenter per ton avfall. Biogasproduktionen minskar miljöpåverkan med 11,6 kg CO2-ekvivalenter per ton matavfall. Förbränning av avfall är den behandlingsmetod som har mer positiv inverkan på växthuseffekten. Energiproduktion med avfall som bränsle är inte hållbart på lång sikt. Avfall är ett ohållbart bränsle, inom EU utförs ett aktivt arbete för att minska uppkomsten av avfall. / Life cycle assessment as a method is used to evaluate products or services from “cradle to grave”. A life cycle assessment of municipal waste incineration with energy recovery is conducted with the software SimaPro. The result is compared with life cycle assessment conducted on biogas production from food waste, the comparison shows the process with the least impact on the environment. Incineration of municipal waste contributes to reduced environmental impact with 63.9 kg CO2-equivalents per ton waste. Biogas production reduces the environmental impact with 11.6 kg CO2-equivalents per ton food waste. Incineration of municipal waste is the treatment with the least environmental impact. Power generation with waste as fuel is unsustainable long term, waste is an unsustainable fuel and the European Union is actively working to reduce the generation of waste.
165

Volatile fatty acid production and application as external carbon source for denitrification / Flyktig fettsyra produktion och applikation som extern kolkälla för denitrifikation

Döhler, Cora Michelle January 2020 (has links)
By rethinking wastewater treatment plants (WWTPs) as resource recovery facilities, it is possible to de- velop the next generation of WWTPs. Moreover, it allows to accomplish environmental goals, such as reducing the CO2 footprint, and comply with increasing effluent standards regarding the concentration of nitrogen in a more sustainable way. This research study aims to analyse the possibility of recirculating carbon within WWTPs in form of volatile fatty acids (VFAs) produced by co-fermentation of primary sludge and food waste. The obtained fermentation liquid is utilised as carbon source to enhance the denitrification process in a post-anoxic denitrification plant setup. Two pilot scale fermentation reactors were semi-continuously operated, systematically varying only in pH. By controlling one reactor to pH 10, while the second reactor was operated without pH control, it was possible to assess the influence of the pH on the carbon recovery process. Despite the pH not being controlled in the second fermentation reactor, it adjusted itself to a stable pH around 5.4. The co-fer- mentation process was monitored by weekly analysis of the SCOD and total amount of VFAs (TVFA). While the alkaline conditions in the reactor operated at pH 10 allowed a higher hydrolysis of the sub- strate, the second reactor, operated without pH control, achieved a more distinct acidification, due to the lower pH. Consequently, the SCOD in the reactor operated without pH control contains a higher percentage of TVFA amounting to 64 % in comparison to the reactor operated at pH 10 with 40 % TVFA. Furthermore, the achieved degree of fermentation was assessed by calculating the net increase of TVFA per gram of VS, respectively VSS. A higher degree of fermentation was achieved without pH control, resulting in a higher VFA yield compared to the fermentation reactor operated at pH 10. Moreover, anal- ysis of the individual VFAs by gas chromatography showed distinct differences in the composition of the fermentation liquids. According to the findings, the reactor operated at pH 10 produced mainly acetic acid (61 %), followed by propionic acid (18 %) and n-butyric acid (14 %). In contrast, the fermentation reactor operated without pH control produced mainly n-caproic acid (47 %), followed by acetic acid (25 %) and n-butyric acid (16 %). Despite the similar fermentation substrate supplied to both reactors, the acidic conditions in the reactor operated without pH control allowed carboxylic acid chain elongation from acetic acid to n-caproic acid, resulting in the main difference of the fermentation liquids. The fermentation liquid of the two reactors was filtered, diluted to a concentration of 5 g COD/L and supplied as additional carbon source to enhance denitrification in two continuously operated pilot scale moving bed biofilm reactors (MBBR), applying a carbon-to-nitrogen ratio of 4.5. One of the denitrifica- tion MBBRs received the carbon recovered by fermentation at pH 10 as external carbon source, whereby the carbon source produced by fermentation without pH control was supplied to the other MBBR. The maximal achieved denitrification rate was quite similar for both MBBRs amounting to 3.25 g NO3- Neq/(m2·d) for the MBBR receiving the carbon source recovered by co-fermentation at pH 10 and 3.38 g NO3-Neq/(m2·d) for the MBBR receiving the VFA-mix obtained by co-fermentation without pH control. However, the MBBR provided with the carbon source recovered by co-fermentation under acidic conditions achieved a higher average denitrification rate of 2.5 g NO3-Neq/(m2·d), compared with the MBBR receiving carbon produced by co-fermentation at pH 10 (1.8 g NO3-Neq/(m2·d)). The lower efficiency of the MBBR supplied with additional carbon recovered by fermentation at pH 10 is caused by an accumulation of NO2-N during the denitrification process. This accumulation of NO2-N indicates suboptimal conditions, both due to the composition of the supplied carbon source and an overall higher pH during the denitrification process, which might supress facultative anaerobes, such as denitrifiers. Nevertheless, this study shows that both VFA-rich carbon sources obtained by co-fermentation of pri- mary sludge and food waste are suitable to enhance denitrification of municipal wastewater, with the carbon source recovered by fermentation without pH control achieving a higher denitrification effi- ciency. / Eine Neuinterpretation kommunaler Klärwerke als Rohstoff-Rückgewinnungsanlagen ermöglicht die Entwicklung der Kläranlagen der Zukunft. Umweltziele, wie die Reduktion des CO2-Fußabdrucks und die Einhaltung steigender Abwasserstandards im Hinblick auf die Stickstoffkonzentration können somit nachhaltiger erreicht werden. Diese Forschungsstudie zielt darauf ab, die Möglichkeit der Rückführung von Kohlenstoff in Kläranlagen in Form leichtflüchtiger Fettsäuren (engl. volatile fatty acids, VFAs) zu untersuchen. Diese VFAs werden durch Co-Fermentation von Primärschlamm und Lebensmittelabfäl- len erzeugt und als zusätzliche Kohlenstoffquelle einer nachgeschalteten Denitrifikation zugeführt, um die Prozesseffizienz zu steigern. Zur Erzeugung der VFAs wurden zwei Fermentationsreaktoren halbkontinuierlich im Pilotmaßstab be- trieben, welche systematisch im pH-Wert variierten. Der Einfluss des pH-Wertes auf den Kohlenstoff- rückgewinnungsprozess konnte beurteilt werden, indem ein Reaktor auf pH 10 geregelt wurde, während dieser im zweiten Reaktor nicht beeinflusst wurde. In diesem stellte sich aufgrund ablaufender Reakti- onen ein stabiler pH-Wert um 5,4 ein. Der Co-Fermentationsprozess wurde durch wöchentliche Analyse des gelösten chemischen Sauerstoffbedarfs (engl. soluble chemical oxygen demand, SCOD) und der Ge- samtmenge an VFAs (TVFA) überwacht. Während die alkalischen Bedingungen in dem bei pH 10 be- triebenen Reaktor eine höhere Hydrolyse des Substrats ermöglichten, erreichte der zweite Reaktor auf- grund des niedrigeren pH-Werts eine stärkere Versäuerung. Folglich enthält der SCOD in dem Reaktor, der ohne pH-Regelung betrieben wurde, mit 64 % einen höheren Anteil an TVFA im Vergleich zu dem bei pH 10 betriebenen Reaktor mit 40 % TVFA. Außerdem wurde der erreichte Fermentationsgrad durch Berechnung der Nettozunahme der TVFA pro Gramm flüchtige Feststoffe (VS) bzw. flüchtige suspendierte Feststoffe (VSS) erfasst. Ein höherer Fer- mentationsgrad konnte ohne pH-Regelung erzielt werden, welche eine höhere VFA-Ausbeute im Ver- gleich zur Fermentation bei pH 10 zeigt. Deutliche Unterschiede in der Zusammensetzung der gewon- nenen VFAs konnten durch Analyse mittels Gaschromatographie erfasst werden. Demzufolge entstand bei der Fermentation bei pH 10 hauptsächlich Essigsäure (61 %), gefolgt von Propionsäure (18 %) und n-Buttersäure (14 %). Im Gegensatz dazu, produzierte der Fermentationsreaktor ohne pH-Regelung überwiegend n-Capronsäure (47 %), gefolgt von Essigsäure (25 %) und n-Buttersäure (16 %). Trotz des gleichen Fermentationssubstrates, welches beiden Reaktoren zugeführt wurde, ermöglichen die sauren Bedingungen in dem Fermentationsreaktor ohne pH-Regelung, eine Verlängerung der Carbonsäureket- ten von Essigsäure zu n-Capronsäure. Nach Filtration der in verschiedenen Milieus gewonnenen Fermentationssubstrate und Verdünnung auf eine Konzentration von 5 g COD/L, wurden diese zwei im Pilotmaßstab kontinuierlich betriebenen Fließbett-Biofilmreaktoren (engl. Moving bed biofilm reactor, MBBR) als zusätzliche Kohlenstoffquelle zur Denitrifikation zugeführt. Über die gesamte Versuchsdauer wurden ein MBBR mit dem alkalisch gewonnenen und der Andere mit dem im sauren Milieu erzeugten VFA-Mix betrieben. Das Kohlenstoff- Stickstoff-Verhältnis (C/N Ratio) lag dabei bei 4,5. Beide MBBRs wiesen eine vergleichbare maximale Denitrifikationsrate von 3,25 g NO3-Neq/(m2·d) (VFAs pH 10) und 3,38 g NO3-Neq/(m2·d) (VFAs pH un- geregelt) auf. Der MBBR, welcher die im sauren Milieu rückgewonnene Kohlenstoffquelle erhielt, er- reichte im Durchschnitt eine höhere Denitrifikationsrate von 2,5 g NO3-Neq/(m2·d) als der MBBR, der den bei pH 10 gewonnenen VFA-Mix erhielt (1,8 g NO3-Neq/(m2·d)). Die im Vergleich geringere Effizi- enz der alkalisch rückgewonnenen Kohlenstoffquelle wird durch eine NO2-N-Anreicherung während der Denitrifikation verursacht, welche suboptimale Bedingungen während des Prozesses indiziert. Dies ist sowohl auf die Zusammensetzung der zugeführten Kohlenstoffquelle, als auch auf einen insgesamt hö- heren pH-Wert während des Reduktionsprozesses zurückzuführen, der fakultative Anaerobier, wie bspw. Denitrifikanten, unterdrücken kann. Dessen ungeachtet zeigt diese Studie, dass beide durch Co- Fermentation von Primärschlamm und Lebensmittelabfällen gewonnenen VFA-reichen Kohlenstoff- quellen zur Verbesserung der Denitrifikation kommunalen Abwassers geeignet sind, wobei die durch Fermentation ohne pH-Regelung erzeugte Kohlenstoffquelle eine höhere Effizienz aufweist. / Det är möjligt att utveckla den nya generationen av avloppsreningsverk genom att ompröva avloppsreningsverk som resursanläggning. Därtill möjliggör det att uppnå miljömål som att minska koldioxidavtrycket och följa ökande utsläppskrav, t.ex. för kvävekoncentration, på ett mer hållbart sätt. Denna forskningsstudie syftar till att analysera möjligheten att återcirkulera kol inom reningsverket i form av lättflyktiga fettsyror (engl. volatile fatty acids, VFAs), producerades genom samfermentering av primärslam och matavfall. Det erhållna fermenteringssubstratet används som extern kolkälla för att förbättra processeffektiviteten i en efterdenitrifikationsanläggning. Två pilotskaliga fermenteringsreaktorer drevs i semikontinuerligt driftläge med endast en skillnad i pH. Det var möjligt att utvärdera pH-påverkan på kolåtervinningsprocessen genom att kontrollera pH- värdet i en reaktor till pH 10, medan den andra reaktorn drevs utan pH-kontroll. På grund av reaktionerna som fortlöpte, justerade sig den icke-kontrollerade reaktorn själv till ett stabilt pH runt 5,4. Samfermenteringsprocessen övervakades genom veckoanalys av kemisk syreförbrukning i filtrerade prover (engl. soluble chemical oxygen demand, SCOD) och total mängd av VFAs (TVFA). Medan den alkaliska miljö i den första reaktorn gynnade en högre hydrolys av substratet, uppnådde den andra reaktorn en mer tydlig surgöring på grund av det lägre pH-värdet. Följaktligen innehåller SCOD i reaktorn som drivs utan pH-kontroll en större andel TVFA – 64 % av SCOD - jämfört med reaktorn som drivs vid pH 10, där TVFA utgör 40 % av SCOD. Vidare analyserades den uppnådda fermenteringsgraden genom att beräkna nettoökningen av TVFA per gram VS, respektive VSS. En högre jäsningsgrad uppnåddes i sur miljö, vilket resulterade i en högre VFA-produktion jämfört med fermenteringsreaktorn som drevs vid pH 10. Därtill visade analys med gaskromtografi av de individuella VFA tydliga skillnader i sammansättning av substraten. Enligt rönen producerade reaktorn vid pH 10 mestadels ättiksyra (61 %) följt av propionsyra (18 %) och n-smörsyra (14 %). Däremot producerade fermenteringsreaktorn utan pH-kontroll mestadels n-kapronsyra (47 %) följt av ättiksyra (25 %) och n-smörsyra (16 %). Detta visar att trots att samma fermentationssubstrat användes för båda reaktorerna möjliggör den sura miljön i reaktorn utan pH-kontroll karboxylkedjeförlängningen från ättiksyra till n-kapronsyra. Fermentationssubstraten av de två reaktorerna filtrerades, utspäddes till en koncentration av 5 g COD/L och tillfördes som extern kolkälla, med ett kol/kväve-förhållande på 4,5, för att förbättra denitrifikationen i två kontinuerliga drivna biofilmreaktorer med rörliga bärare (engl. moving bed biofilm reactor, MBBR). En MBBR erhöll under hela experimentets gång den kolkälla som bildats under alkaliska förhållanden och den andra MBBR:en erhöll motsvarande kolkälla som bildats i den sura miljön i fermenteringsreaktorn utan pH-kontroll. Den maximala uppnådda denitrifikationskapaciteten var ganska likartad för båda MBBR: 3,25 g NO3-Neq/(m2·d) för den MBBR som opererades med den alkaliska erhållen kolkällan och 3,38 g NO3-Neq/(m2·d) för MBBR som erhöll den utspädda fermenteringsvätskan bildad utan pH-kontroll. Emellertid uppnådde den MBBR som erhöll kolkällan bildad i sura miljön en högre genomsnittlig denitrifikationskapacitet på 2.5 g NO3-Neq/(m2·d) jämfört med MBBR som fick kolkällan producerad genom fermentering vid pH 10 (1.8 g NO3-Neq/(m2·d)). Den lägre effektiviteten i den MBBR som fick den alkaliskt erhållna kolkällan orsakas av en ansamling av NO2-N under denitrifikationsprocessen, vilket indikerar suboptimala förhållanden. Detta beror både på sammansättningen av den tillförda kolkällan och ett högre totalt pH-värde under reduktionsprocessen, vilket kan hämma fakultativa anaerober såsom denitrifierare. Trots det visar denna forskningsstudie att båda de VFA-rika kolkällorna erhållna genom samfermentering av primärslam och matavfall är lämpliga för att förbättra denitrifikationen av kommunalt avloppsvatten, varvid kolkällan som produceras genom fermentering utan pH-kontroll uppnår en högre denitrifikationseffektivitet.
166

Three essays on reducing waste in restaurants

Shu, Yiheng 09 September 2022 (has links)
No description available.
167

Investigating Radical High-Involvement Eco-Innovations: The Case of Household Biogas in the U.S.

Dowell, Zachary David 07 June 2024 (has links)
There is an emerging market of radical eco-innovations that require high involvement from the U.S. consumer for successful routinization. Yet, there exists a gap in knowledge that guides the dissemination of such innovations for related stakeholders. Among these innovations is the household digester (HD), which is marketed as an innovation capable of generating biogas and fertilizer through processing organic waste at its point-of-source (POS). The HD may surpass other high-involvement eco-innovations in respect to levels of involvement necessary for consumer routinization and sustained operation. However, previously unexplored factors within the contemporary U.S. landscape have spurred recent growth in HD adoption. This dissertation took a three-manuscript approach in the investigation of factors that influence the adoption and diffusion of HD in the U.S. The first of three studies tested a literature-based conceptual model framed within the multi-level perspective (MLP) to identify barriers and drivers of HD adoption. Qualitative data from expert interviews and social media posts inform the production of a taxonomy of complexities that depict the current state of HD in the U.S. Findings indicate that HD marketing during the Covid pandemic brought forth new adopter populations seeking resilience due to infrastructure distrust. The second study investigated motivations for HD adoption through operationalizing constructs from psychology literature and diffusion of innovation theory (DOI). Through in-depth interviews with adopters, the factors of relative advantage, compatibility, and cost were found to outweigh pro-environmental behavior (PEB) in adoption decisions. Furthermore, high-involvement was not found to influence adoption decisions. The final study employed a collective case study approach that explored paths to HD routinization among ten adopters. Results highlight the ability of adopters to overcome technical challenges through reinventions necessary for contextual adaptations. This dissertation contributes insights into the adoption and diffusion of radical high-involvement eco-innovations, offering implications for policy, practice, and future research in emerging innovations interacting within socio-technical transitions. / Doctor of Philosophy / A variety of emerging products are entering the U.S. consumer market that promote household sustainability, many of which require high levels of involvement from consumers for successful adoption. These high-involvement eco-innovations have been studied within the context of electric cars, organic foods, and other products that require extensive consumer research before purchase. However, this research focuses on a new product entering the U.S. market where involvement not only requires extensive pre-purchase research but also radical levels of interaction during operation and maintenance for successful product use. The household anaerobic digester is an apparatus that turns organic waste into cooking fuel and fertilizer. This innovation has been widely adopted in the developing world with some success, but technical issues during operation have been shown to result in discontinued use. This dissertation focuses on the adoption of household digesters in the U.S. Radical high-involvement eco-innovations need further scientific analysis to understand what factors might affect adoption, as well as explore the viability of such products entering a market where convenience is a social norm. This research aims to provide an analysis of this phenomenon through three studies. Chapter Two explores this new product and factors that may hinder or accelerate adoption in the U.S. Experts in the field of household digesters are interviewed for data collection, as well as analysis of social media posts where new adopters share information. This study aims to determine the social and technical complexities of Americans adopting household digesters. The Third Chapter assesses the purchase motivations of current adopters of household digesters in the U.S. This assessment takes place through interviews, where consumers provide information about their traits, values, and the degree to which they use the product to replace an existing technology. Chapter Four takes a further look at adopters to gain an understanding of paths to adoption and commonly shared practices that are employed to be successful in the adoption of household digesters. This study first presents the stories of each adopter and then provides a cross-case analysis that reveals commonalities of adopters regarding how paths to adoption often lead to shared practices for successful HD operation. The work is summarized in Chapter Five with conclusions, lessons learned, and recommendations for future research. This includes drawing connections between the three studies' findings and how the studies' chronology brought forth validation in the instruments used for data collection.
168

The Effect of Ownership on Consumers' Disposal Decisions: Research on Food Wastage and Recycling Behaviors

Xie, Jieru 11 April 2022 (has links)
Research in consumer behavior has focused predominantly on how consumers make purchase decisions. However, much less attention has been directed toward examining post-purchase behaviors. In this dissertation, I examine how ownership affects individuals' disposal decisions of their current possessions. In essay 1, I investigate how differences in duration of ownership affect consumers' food waste behaviors. I demonstrate that the same food products are more likely to be wasted as well as wasted more of when they are owned for a longer duration (vs. purchased more recently). I also delineate how this wastage can be reduced. In essay 2, I explore how a specific post-ownership experience, evaluations (positive vs. negative), influences consumers' recycling behaviors, even when these evaluations (e.g., taste of a drink) do not affect recyclability (e.g., of the bottle). I demonstrate that consumers will be more likely to recycle products associated with positive (vs. negative) evaluations, and, thus, will be more likely to recycle a drink's bottle when the taste is evaluated more positively. / Doctor of Philosophy / When thinking about the field of consumer behavior, most might believe it to involve studying how consumers evaluate products and make purchase decisions. Very few might believe that studying post-purchase behaviors also falls within the realm of consumer behavior. Unfortunately, these beliefs are quite common, and are not held by lay people alone. In fact, in the past, even researchers thought of consumer research as being synonymous with buyer behavior. However, researchers now recognize that consumer behavior is a dynamic ongoing process, which does not just start and end with product purchase. In this dissertation, I focus on one type of consumers' post-purchase behavior, disposal decisions. Specifically, I look at how ownership affects individuals' disposal decisions of their current possessions. In essay 1, I focus on consumers' food waste behavior. I study how differences in how long they have owned a food product (duration-of-ownership) affect their food evaluations as well as food waste behavior. I find that even when two food products are otherwise identical (i.e., same manufacturing/expiration dates, not expired, previously unopened), consumers are more likely to waste as well as waste more of the one purchased earlier (a longer duration-of-ownership) than that purchased more recently (a shorter duration-of-ownership). I also suggest one strategy to help reduce this food wastage. In essay 2, I focus on consumers' recycling behavior. I study how product evaluations affect consumers' recycling decisions. I find that even when these evaluations (e.g., taste of a drink) have nothing to do with the container (e.g., bottle of the drink), consumers are more likely to recycle the drink's bottle when they like the taste than when they do not like the taste of the drink.
169

The Effect of a Trace Element Supplement on the Biomethane Potential of Food Waste Anaerobic Digestion

Graff, Kelly Mackenzie 15 June 2022 (has links)
Food waste is a desirable feedstock for anaerobic digestion because it is high in moisture and is an easily degradable material. However, mono-digestion of food waste often fails due to the accumulation of volatile fatty acids. Supplementing trace elements is one strategy to combat this issue. This study examined the effect of supplementing trace elements (iron, nickel, selenium, molybdenum, magnesium, zinc, calcium, copper, manganese, cobalt) on the methane yield and organic waste destruction of anaerobically digested food waste. Methane yield of food waste with and without the inorganic salt trace element was determined by the gas density-based biomethane potential method at mesophilic (37°C) conditions over 30 days. The three treatments were inoculum only, food waste and inoculum, and food waste and inoculum with an added trace element solution. There was no significant difference between treatments in terms of waste stabilization (percent volatile solids, total solids, and total chemical oxygen demand reduction) between treatments. The average cumulative biogas produced was 41% higher, and the average total cumulative methane produced was 23% higher in the treatment with the trace element supplement. Mean methane yield was not different (p > 0.05) between treatments over the 30 days, and there was no difference (p > 0.05) in biomethane potential between treatments. In addition, greenhouse gas reduction potential was estimated from food waste streams in Montgomery, VA using anaerobic digestion. The purpose of this work was to (1) estimate the total mass of food waste produced in Montgomery, VA in a year, (2) use the results from the biomethane potential analyses to inform the sizing of a theoretical community digester in Montgomery, VA, and (3) estimate the greenhouse gas reduction potential of anaerobically digesting the food waste instead of sending it to landfill. Greenhouse gas reduction was calculated using the Climate Action Reserve Organic Waste Digestion Project Protocol guidelines. The greenhouse gas reduction potential was estimated as 6,532 tonnes of carbon dioxide equivalent per year (tCO2e/year), with approximately 693 m3 methane produced per day. In one year, the digester would generate an estimated 7370 kWh of energy which has the potential to power 149 homes for a year in Montgomery, VA. In addition, 4130 tonnes/year of composted digestate would be available as fertilizer for surrounding farms. / Master of Science / Currently, about one-third of the entire U.S. food supply is lost or wasted. A large portion of that food waste is sent to landfills, where it produces methane, a greenhouse gas. Instead, food waste can be broken down to produce biogas during anaerobic digestion. Anaerobic digestion is a process in which microorganisms break down organic materials in the absence of oxygen to produce biogas and digestate, a material used as a soil amendment or fertilizer. However, anaerobically digesting food waste often leads to process instability and failure due to a buildup of undesirable intermediates. Microorganisms in anaerobic digestion require certain trace elements (i.e., iron, copper) that food waste often lacks; therefore, supplementing key trace elements may improve the anaerobic digestion of food waste. This research aimed to assess the effect of supplementing key trace elements (iron, copper, zinc, calcium, magnesium, nickel, manganese, selenium, molybdenum, cobalt) on organic matter degradation and methane yield. Methane yield of food waste with and without the inorganic salt trace element was determined by the gas density-based biomethane potential method at mesophilic (37°C) conditions over 30 days. The average cumulative biogas produced was 41% higher, and the average total cumulative methane produced was 23% higher in the bottles containing a trace element supplement. No significant difference was seen in the two groups when comparing organic matter degradation. These results demonstrate that supplementing trace elements can improve biogas and methane production. Greenhouse gas reductions from anaerobically digesting food waste instead of sending it to landfills were determined for Montgomery, VA. The results from the biomethane potential test informed the design of a theoretical community digester. Greenhouse gas reduction was calculated using the Climate Action Reserve Organic Waste Digestion Project Protocol equations. The greenhouse gas reduction was determined as 6,532 tonnes of carbon dioxide equivalent per year (tCO2e/year). The digester would produce approximately 693 m3 methane/day, which has the potential to power 149 homes for a year in Montgomery, VA. In addition, 4130 tonnes/year of compost would be produced and available as a fertilizer for surrounding farms.
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Managing food security through food waste and loss: Small data to big data

Irani, Zahir, Sharif, Amir M., Lee, Habin, Aktas, E., Topaloğlu, Z., van't Wout, T. 11 March 2017 (has links)
Yes / This paper provides a management perspective of organisational factors that contributes to the reduction of food waste through the application of design science principles to explore causal relationships between food distribution (organisational) and consumption (societal) factors. Qualitative data were collected with an organisational perspective from commercial food consumers along with large-scale food importers, distributors, and retailers. Cause-effect models are built and “what-if” simulations are conducted through the development and application of a Fuzzy Cognitive Map (FCM) approaches to elucidate dynamic interrelationships. The simulation models developed provide a practical insight into existing and emergent food losses scenarios, suggesting the need for big data sets to allow for generalizable findings to be extrapolated from a more detailed quantitative exercise. This research offers itself as evidence to support policy makers in the development of policies that facilitate interventions to reduce food losses. It also contributes to the literature through sustaining, impacting and potentially improving levels of food security, underpinned by empirically constructed policy models that identify potential behavioural changes. It is the extension of these simulation models set against a backdrop of a proposed big data framework for food security, where this study sets avenues for future research for others to design and construct big data research in food supply chains. This research has therefore sought to provide policymakers with a means to evaluate new and existing policies, whilst also offering a practical basis through which food chains can be made more resilient through the consideration of management practices and policy decisions.

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