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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.
101

The connection between the issue of food waste and its collection for biogas : A case study in the municipality of Stockholm

Blomgren, My January 2013 (has links)
Reduction is the best way of handling the issue of food waste, however, considering the difficulties of achieving reduction, a collection of waste for a potential decrease was established. The thesis consist of an examination between two subjects, the issue of food waste and the waste management system of collecting food waste to produce biogas, where the main focus is upon the municipality of Stockholm. The purpose of the study was to analyze the issue of food waste and connect it to the process of collecting food waste to produce biogas, and examine the potential benefits and conflicts between these two topics. The aim was also to investigate the process possibilities and functionality, and how the procedure is operating in the municipality of Stockholm. Besides a litterature study, four interviews were conducted with respondents from authorities and the municipality. The results show that the process of collecting food waste to produce biogas is a great procedure. It is a good alternative for the environment and generates to a substitute towards fossil fuel. However, whether the process is a benefit for the issue of food waste seems to be rejected. There are also difficulties of apprehending the connection between the two subjects, since they are seen as topics that lie collaterally to each other. In the municipality of Stockholm, the process function within the section of restaurants, however, it is not that fortunate within households. The factors of simplicity, profitability and trust are the main features threatening the success of the process of collecting food waste to produce biogas. One may presume that the goal/requirement firsthand is to focus upon reduction of food waste. However, there seems to be a shift from consuming less (reduce the waste) to consuming differently (reuse the waste) nowadays, hence the process of collecting food waste to produce biogas is central.
102

Hygienisering av torkat bioavfall

Svensson, Malin January 2007 (has links)
The main project Dry preservation of food waste from households includes a new technique concerning drying and storage of dried biowaste as well as a study of the sorting of household waste and further usage of the dried biowaste. A question asked in the project is, can the dried biowaste be used as a soil amendment? If organic waste is used as a soil amendment, precaution concerning hygienic safety risks has to be accounted for. The objective of this M. Sc. Thesis Work was to first find a suitable method to attain hygienic safety through a literature study, to test and evaluate the method and to test if a method changes the composition or structure of the material. An existing recipe for food waste was developed and used throughout the work. Heating of the dried biowaste is probably the most suitable method to reach and attain a hygienically safe product. Three time-temperature proportions were tested, 55, 70 and 80°C. The results show that a raise in temperature lead to a change in the composition of the dried biowaste, most distinctively for the highest temperature. Nitrogen losses of 21% of the total nitrogen content were noticed. A composting experiment showed that the biowaste heated to the highest temperature was decomposed to a higher degree. It does not, however, seem like a heating process will decrease the possibility to use dried biowaste as a soil improvement. / Projektet Torrkonservering av matavfall från hushåll innefattar en ny teknik för torkning och lagring av bioavfall, hushållens sortering och vidare användning av det torkade materialet. För att sluta det naturliga kretsloppet utreds om det torkade bioavfallet kan användas som ett jordförbättringsmedel. När organiskt avfall ska användas som ett jordförbättringsmedel ställs krav på hygienisk säkerhet. Examensarbetets syfte var att, genom litteraturstudier, utreda lämplig hygieniseringsmetod att vidare testa praktiskt, samt att testa om en hygieniseringsprocess medför några förändringar på det torkade bioavfallets materialegenskaper. Ett befintligt standardrecept på matavfall vidareutvecklades och användes. Resultaten tyder på att upphettning av det torkade bioavfallet förmodligen är den mest lämpliga hygieniseringsmetoden. Tre olika tid- temperaturförhållanden testades, 55, 70 och 80°C. Laborationer och analyser tyder på att det torkade bioavfallet genomgår en viss förändring av den kemiska sammansättningen vid upphettning, vilket är tydligast för den högsta hygieniseringstemperaturen. Bland annat sker kväveförluster på upp till 21 % av totalkvävet. Komposteringstester visar på att nedbrytningsgraden är högst för bioavfall som hygieniserats vid den högsta temperaturen. Det verkar inte som om hygienisering, genom upphettning, minskar möjligheten att använda torkat bioavfall som ett jordförbättringsmedel.
103

Matavfall från livsmedelsbutiker : - En analys av den kommunala hanteringen i Sverige samt en detaljstudie av förhållandena i Umeå kommun

Andrée, Erik, Schütte, Johan January 2010 (has links)
Food waste from grocery stores - An analysis of municipal management inSweden and a detailed study of the situation in Umeå municipality The objective of this thesis was to analyze the municipal management of food waste fromgrocery stores in Sweden in general and in Umeå municipality in particular. Furthermore theobjective was to account for the different waste treatment methods that can be used and toevaluate them from an environmental perspective. In order to analyze the municipalmanagement a survey was sent to all of the municipalities/municipal waste companies inSweden. A general comparison of treatment methods was carried out on the basis of ascientific review and a system analysis was performed in order to compare three differenttreatment alternatives for the food waste generated in grocery stores in Umeå. The surveyshowed that the legal definition of food waste from grocery stores is unclear and variesbetween municipalities. However, a majority of the municipalities that offer any kind ofsource separation include grocery stores in the offer. The packaged food waste is oftenincinerated even if source separation is available due to the difficulties with removingpackaging materials. Concerning treatment methods, the results show that composting is theenvironmentally least advantageous method for large-scale treatment of food waste.Incineration and anaerobic digestion are about equal in their environmental impact, but thelatter was found to be favorable in principle based on the fact that it, in theory, generates bothnutrient recycling and energy recovery. For the food waste generated in grocery stores inUmeå municipality, incineration at the Dåva power and heating plant was found to be thepreferable method rather than anaerobic digestion in Skellefteå and composting in Luleå.
104

Biogaspotential hos rejektfraktionen från biogasanläggningen Kungsängens gård / Biogas potential of the reject fraction from the biogas plant Kungsängens gård

Malmros, Peter January 2011 (has links)
Den totala biogasproduktionen i Sverige 2009 var 1,4 TWh och 22 % av biogasen producerades i samrötningsanläggningar. Sedan 2005 är det förbjudet att deponera organiskt avfall, vilket har gjort att produktionen från samrötningsanläggningar har ökat de senaste åren. Den totala biogaspotentialen i Sverige är ungefär 15 TWh och där står lantbruket för över 70 %. Avloppsslam, avfall från livsmedelsindustrin och matavfall står för den resterande delen. Det är även dessa tre råvarugrupper som har störst lönsamhet med dagens teknik. Av dessa råvarugrupper finns den största kvarvarande potentialen hos matavfall. Problemet med matavfall är att det ofta innehåller föroreningar som måste sorteras bort för att inte orsaka driftstörningar. Detta orsakar ofta problem på grund av att organiskt material hamnar i rejektet.    Kungsängens gård är en samrötningsanläggning som producerar biogas från olika typer av organiska restprodukter. Under 2009 behandlades 7 536 ton material, av detta var 58 % matavfall. Av inkommande material sorterades 938 ton ut och lämnade anläggningen som rejekt. Under 2011 förväntas mängden inkommande material öka. Dessutom förväntas andelen matavfall öka till 90 % vilket kommer att ge ännu större rejektmängder. Syftet med detta examensarbete var att genom analyser och satsvisa utrötningsförsök bestämma den kemiska sammansättningen samt metanpotentialen hos de olika rejektfraktionerna från biogasanläggningen Kungsängens gård. En utredning gjordes för att undersöka vilka möjligheter och tekniker som potentiellt skulle kunna användas för att framställa biogas av rejektet och också vilka möjligheter som finns för att effektivisera befintlig utrustning. Resultatet från utrötningsförsöken visade att metanpotentialen för de olika rejektfraktionerna var hög och kan jämföras med vad som kan förväntas av källsorterat matavfall. Om rejektet som producerades under 2010 skulle användas för biogasproduktion skulle denna metanpotential motsvara 10 % av den totala biogasproduktionen vid Kungsängens gård under 2010. Utredningen visar att det bästa alternativet för att röta rejektet i sitt befintliga skick är satsvis torrötning. Osäkerheten kring torrötning är dock stor på grund av att det i Sverige inte finns några torrötningsanläggningar och därmed är kunskapsnivån relativt låg. / The biogas production in Sweden in 2009 was 1,4 TWh and 22 % of the biogas was produced in co-digestion plants. Since 2005 it is prohibited to deposit organic waste and this has resulted in an increased biogas production from this type of waste materials in recent years. The total biogas potential in Sweden is approximately 15 TWh and 70 % of that comes from agriculture wastes. Sewage sludge, waste from food industry and food waste accounts for the rest. It is also these three commodity groups that have the greatest profitability with today's technology. Among these groups, food waste have the largest remaining biogas potential. The problem with food waste is that it often contains impurities that must be sorted out in order to avoid operational problems. The out sorting process often causes problems and typically organic material is lost in the reject fraction. The biogas plant Kungsängens gård is a co-digestion plant that produces biogas from different types of organic residues. In 2009 about 7 536 tons of material were treated, of which 58 % was food waste. Of the incoming material 938 tons were sorted out as reject. In 2011 the amount of incoming material is expected to increase. In addition, the proportion of food waste is expected to increase to 90 %, which will result in even larger amounts of reject. The purpose of this study was to perform analysis and batch digestion experiments to determine the chemical composition and methane potential of the reject from the biogas plant Kungsängens gård. An investigation was also made to examine methods and technologies that potentially could be used to produce biogas from the reject. The results from the batch digestion experiments showed that the methane potential of the different reject fractions was high and it can be compared with what might be expected of source separated food waste. If the reject that was produced in 2010 would be used for biogas production, this methane potential is equal to 10 % of the total production of biogas at Kungsängens gård in 2010. The investigation shows that dry fermentation with a batch system is the only technology that potentially could produce biogas from the reject in its existing form. There are no dry fermentation plants in Sweden and therefore the level of knowledge is relatively low. Because of that it is hard to estimate the profitability and efficiency of dry fermentation plants.
105

Research And Product Design To Minimize Food Waste In Western Domestic Kitchens

Bektes, Ahmet 01 September 2010 (has links) (PDF)
The aim of this thesis is to explore design directions to minimize a food wastage problem in western domestic kitchens. Central to the thesis is an understanding of people&rsquo / s behavior towards the food waste phenomenon. Three interconnected studies and one design project are included. In Study I, 18 participants were interviewed to explore their perceptions and attitudes towards food waste, revealing the most wasted food types and reasons for food wastage. The findings of Study I are clustered under four phases of food handling: acquisition, preparation, consumption and storage. Study II comprised a generative session with three users and two designers, devised to explore latent and tacit knowledge regarding food wastage. Study II resulted in user-generated ideas for minimizing food waste, which were analyzed so as to reveal possible design directions. From these results, a set of criteria for a &lsquo / perfect&rsquo / kitchen appliance, which could minimize food waste, was drawn-up. The design project took the research findings of Study I and II and devised a collection of design concepts as possible ways to help reduce domestic food waste. Two concepts &ndash / Philips Dispense and Canvas - are taken further because they relate to the most wasted food types: &lsquo / bread&rsquo / and &lsquo / vegetables and fruits&rsquo / . In Study III, Philips Dispense and Canvas were evaluated with a questionnaire. According to the results, in households containing busy couples without children, Philips Dispense is valued highest (it takes the food waste responsibility away from users) whereas Philips Canvas was valued lower (it gives feedback on current stocks and persuades homeowners not to waste food).
106

龍碧雅寶農 : 綠色農業專家,社區與農民之友 / Lombriabono: helping farmers and communities using green agriculture

蘇和, Astorga Solano, Jose B. Unknown Date (has links)
龍碧雅寶農 : 綠色農業專家,社區與農民之友 / Social enterprises are the solution to many of today’s global problems. Although great efforts have been made by nongovernmental organizations and charity, there is still a gap between the world’s most fortunate and less fortunate. In Nicaragua two of the biggest issues are malnourishment and waste management. Both reinforced by the amount of poverty in the country. LOMBRIABONO looks to bridge the gap in malnourishment while alleviating waste management in the country. LOMBRIABONO will involve the communities of the state of Carazo in waste management. The people of Carazo will recycle food waste and hand it to one of our partners in the markets. They in turn will receive payment in the form of food for their efforts and their waste. We will then collect the food waste, process it and turn it into vermicomposting, which is an organic fertilizer made with the use of red worms that presents many benefits to the soil, crops and overall health of the population, later selling the vermicomposting, vermicomposting tea and red worms to sustain our business model. The time is now for our product as people are catching on to the benefits of green agriculture. With the industry being in its embryonic stage, with the proper use of marketing and advertising we will reach thousands of households and bridge that gap caused by poverty all while inspiring other entrepreneurs to start similar ventures.
107

Minimera matsvinn : En studie om livsmedelsbutikers och kunders arbete och medvetenhet kring matsvinn

Enarsson, Marie January 2015 (has links)
Sverige är ett land som är bra på att ta hand om det avfall som uppstår. Mängden matavfall ökar hela tiden och händer ingenting snarast så kommer det finnas dubbelt så mycket om 20 år. Om en hållbar utveckling ska uppnås så måste mängden avfall som kastas minskas drastiskt. Naturvårdsverket har på uppdrag av regeringen föreslagit att matavfallet ska minska med 20 procent fram till år 2020, till skillnad mot år 2010. Sverige kastar 1,9 miljoner ton matavfall varje år. En stor del av detta är mat som faktiskt hade kunnat ätas, om det hanterats annorlunda. Matsvinn är ett globalt problem som uppstår i hela världen men även i hela livsmedelskedjan. Olika studier visar på att stora mängder mat kasseras i onödan varje dag. Det är olika svårt att minska matsvinnet i de olika stegen i livsmedelskedjan. Svårighetsgraden beror på hur mycket matsvinn de olika stegen erhåller. Ju längre produkterna har färdats i kedjan, desto mer energi och resurser har gått till spillo. Denna studie syftar på att ta reda på hur livsmedelsbutiker hanterar matsvinn men även kundernas medvetenhet kring ämnet. Semistrukturerade intervjuer med de ansvariga på frukt och grönt och ”på- stan-intervjuer” med kunder har genomförts i tre olika livsmedelsbutiker för att få fram en bild i hur matsvinn hanteras både hemma och i butiker. Resultatet visade på att livsmedelsbutikerna är medvetna kring ämnet och har förebyggande åtgärder i rutin för att hålla nere svinnet men att de ändå kan bli bättre. Samtidigt vill butikerna sälja så mycket varor som möjligt vilket skapar en komplex värld. Kunderna i de studerade butikerna visar på att de flesta tänker på hur mycket matsvinn de har hemma men att de sen inte vill eller kan intresserad sig för livsmedelsbutikernas svinn. Studien visade även på att det finns skillnader mellan kön- och åldersgrupper bland kunderna vilket är ett intressant resultat. / Sweden is a country that is good at taking care of the waste that arises. The amount of food waste is increasing continuously and if nothing happens soon there will be twice as much in 20 years. If sustainable development is to be achieved, the amount of thrown waste must be reduced. Naturvårdsverket (environmental protection agency) has suggested by commission of the government that food waste will decrease by 20 percent by 2020, unlike in 2010. Sweden throws 1.9 million tons of food waste every year. A large part of this is food that actually could have been eaten, if handled differently. Food loss is a global issue, which occurs in the whole world but also in the entire food chain. Various studies show that large quantities of food are discarded unnecessarily every day. It ́s different to reduce food loss in different steps in the food chain, depending on the food loss receiving in the various steps. The longer the products have been in the chain, the more energy and resources have been wasted. This study aims to find out how grocery stores handle food loss but also customers awareness around the topic. Semi-structured interviews with the responsible for the studied section, and "at-town interviews” with the costumers, have been conducted in three different grocery stores to obtain an image of how food loss is managed both at home and in stores. The results showed that food stores are conscious about the subject and have preventive measures in the routine to keep down losses, but they can always be better. At the same time stores will sell as much merchandise as possible which creating a complex world. Customers in the studied stores shows that most people thinking of food loss at home but that they don’t want to or can be interested for the grocery stores wastage. The study also shows that there is a difference between gender and ages, which is a rather interesting result.
108

Shop More, Buy Less: A Qualitative Investigation Into Consumer Decisions That Lead To Food Waste In U.S. Households

Ligon, Victoria K. January 2014 (has links)
Estimates suggest that 40% of the food grown in the United States ends up in landfills. Household losses are the highest contributor to volume of waste overall, and individual households are estimated to discard around 15% of their total acquired food inventory. Consumers are generally waste averse and a vast majority have been shown to object to wasting food in particular, yet almost all consumers discard a substantial volume of potentially edible food each year. This exploratory qualitative study sought to uncover underlying psychological mechanisms behind this discrepancy between attitude and behavior by exploring the decision-making processes that consumers engage in as they acquire, prepare, consume and discard food. By exploring the patterns of thinking that shape household provisioning practices through an initial in-depth interview, a two-week long household food diary and a follow-up interview with 17 diverse consumers, a grounded theory emerged to explain this counter-intuitive behavior pattern. Extending research from behavioral economics and decision making literature, data from this study suggests the following: 1) people evaluate cost of goods based on incomplete value estimations that fail to account for the costs associated with discarding potentially edible foods; 2) costs associated with the act of shopping are salient and encourage less frequent provisioning trips; 3) people do not adequately account for costs associated with overbuying and storing food; and 4) consumer strategies aimed at maximize efficiency in food acquisition through less frequent shopping trips may actually result in increased inefficiency in the form of greater waste and higher overall cost of goods. Based on emergent findings, a strategy for waste avoidance is presented along with managerial implications.
109

Lagringstidens påverkan på metanpotentialen i matavfall

Hellman, Emil January 2015 (has links)
Biogas är en förnyelsebar energikälla som tillverkas genom att organiskt material som matavfall bryts ner av mikroorganismer under anaeroba (syrefria) förhållanden. Regeringen har satt upp mål för en högre matavfallsutsortering vilket leder till ökad mängd tillgängligt substrat till biogasproduktion. Matavfallet som samlas in börjar brytas ner under tiden det transporteras och lagras. Syftet med studien var att undersöka hur länge matavfall lagras, ta fram ett representativt recept på ett genomsnittligt matavfall i Sverige och utvärdera hur mycket metanpotential som försvinner från matavfall med avseende på lagringstid, insamlingssystem (papper- och plastpåse) och lagringstemperatur (22°C och 6°C) genom laboratorieförsök. Den genomsnittliga lagringstiden för matavfall från villor och flerbostadshus i undersökningen var sex dagar. Ett recept för matavfall har tagits fram med hjälp av litteratursökning och modifiering av recept i Avfall Sveriges rapport U2010:10. Laboratorieförsöken visade att skillnaden i metanpotential mellan plast och papper var tydlig vid 22°C, då metanpotentialen sjunker, men obefintlig vid 6°C. För att uppnå maximal metangasproduktion från matavfall under den varma delen av året så är plastpåsar bättre då de har en mer konserverande effekt på matavfallet än papperspåsar. Detta kan relateras till att plast är tätare än papper och därför håller inne flyktiga ämnen. / Biogas is a renewable energy source that is produced when organic materials like food waste is degraded by microorganisms under anaerobic (oxygen-free) conditions. The Swedish Government has set goals for a higher sorting of food waste, leading to increased amounts of available substrate for biogas production. Collected food waste begin to break down during the time it is transported and stored. The purpose of this study was to investigate the length of the storage, produce a representative recipe for an average food waste in Sweden and evaluate how much methane potential is lost from food waste with respect to the storage time, collection method (paper or plastic bag) and storage temperature (22°C and 6°C) through laboratory tests. The average storage time of food waste from houses and apartment buildings in the survey was six days. A recipe for food waste has been developed with the help of literature search and modification of recipes in ‘’Avfall Sverige’’ report U2010:10. Laboratory tests showed that the difference in methane potential between the plastic and paper were clear at 22°C, with decreasing methane potential, but non-existent at 6°C. To achieve maximum methane production from food waste during the warmer part of the year, plastic bags are better because they have a preservative effect on the food waste. This can be related to the fact that plastic are denser than paper and therefore holds volatile compounds better.
110

Towards a Zero Waste Vision using Insects – Urban Farming producing New Values in a Swedish Supermarket

Ingvarsson, Josef January 2018 (has links)
The premise of the thesis is that current food systems are unsustainable. In fact, as the global population continues to rise, food systems are under greater strain to deliver quality output in a sustainable way. In sustainable food systems, effective use of agricultural land and reducing food waste are central, as stipulated by Agenda 2030 target to reduce food waste by 50 % to 2030. Insects have gained attention for their ability to effectively convert feed, including feed from food waste, to edible products. Framed by a literature review and an analysis of food waste data from a Swedish supermarket, the ability to rear three insect species, House Cricket (Acheta Domesticus), Yellow Mealworm (Tenebrio Molitor) and Black Soldier fly (Hermetia Illucens) on food waste is examined. The three insect species with the addition of laying hens are also the grounding for evidence-based scenarios. The results indicate that the Black Solider Fly can be reared on unprocessed food waste while the House Cricket requires food waste treated for higher levels of protein and phosphorus and the Yellow Mealworm food waste supplemented by external products such as yeast, carrots or wheat bran. The result from the scenarios shows that substantial amounts of edible output can be produced by providing the insects and laying hens vegetable food waste from the supermarket. The conclusion of this thesis highlights the potential of using insects and laying hens as feed converters in integrated production systems to recover energy and nutrients from food waste and thereby contribute to a food system that produces more output using less land and with less negative environmental impact.

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