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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.
121

Propuesta de instalación de una planta productora de compost en el distrito de Pátapo para satisfacer la demanda

Sales Fernandez, Ricardo Erick January 2023 (has links)
La presente investigación tiene como propósito elaborar un estudio de pre-factibilidad para la instalación de una planta productora de compost en el distrito de Pátapo, aprovechando los residuos orgánicos para satisfacer la demanda de abono orgánico, para ello se plantearon tres objetivos: evaluar la pre-factibilidad comercial, técnica y financiera. En base a ello, se obtuvo que para el año 2026 se tiene una demanda insatisfecha de 4 111 421 toneladas de abono orgánico, donde el precio de venta de los sacos de 50 kg de compost para ese mismo año sería de S/61,58. En relación al aspecto técnico, dicho distrito para el año 2026 estaría generando un total de 16 578,37 kg de residuos sólidos al día, de las cuales el 74,86% está representado por residuos orgánicos, para ello la planta requiere de un área total de 4 423,03 𝑚2 de acuerdo al Método de Guerchet y estaría ubicado en el mismo distrito, donde se estaría empleando un sistema de compostaje cerrado y la capacidad diseñada sería 31 sacos/h. Así mismo referente al aspecto financiero, se requiere una inversión total de S/ 7 097 607,70, de las cuales el 76,4% se estaría financiando y como indicador de rentabilidad presenta un VAN de S/ 4 181 709,36 mientras que en el costo beneficio sería que por cada S/1 invertido, se estaría ganando S/2,50. En síntesis, es viable la instalación la planta de acuerdo a sus tres aspectos evaluados, donde se estaría cumpliendo con el 8,15% de la demanda nacional insatisfecha para el año 2026. / The purpose of this research is to prepare a pre-feasibility study for the installation of a compost production plant in the district of Pátapo, taking advantage of organic waste to meet the demand for organic fertilizer, for this, three objectives were proposed, which are to evaluate the commercial, technical and financial pre-feasibility. Based on this, it was obtained that for the year 2026 there is an unsatisfied demand of 4 111 421 tons of organic fertilizer, where the sale price of the 50 kg bags of compost for that same year would be S / 61,58. In relation to the technical aspect, said district by 2026 would be generating a total of 16 578,37 kg of solid waste per day, of which 74,86% is represented by organic waste, for this the plant requires an area total of 4 423,03 𝑚2according to the Guerchet method and would be located in the same district, where a closed composting system would be used and the designed capacity would be 31 bags / h. Likewise, regarding the financial aspect, a total investment of S / 7 097 607,70 is required, in which 76,4% would be financed and as an indicator of profitability it presents a VAN of S / 4 181 709,36 while that the cost benefit would be S / 3,50. In summary, the installation of the plant is viable according to its three evaluated aspects, where it would be meeting 8,15% of the unsatisfied national demand by 2026.
122

An economic analysis of the impact of removing organic waste from small scale cage aquaculture systems in irrigation dams in the Western Cape

Gumbo, Tichaona 03 1900 (has links)
Thesis (MScAgric (Agricultural Economics))--University of Stellenbosch, 2011. / ENGLISH ABSTRACT: The rising demand of fish due to population growth coupled by stagnation of fish supply from natural capture has led the world to turn to aquaculture to fill in the gap between fish supply and demand. Aquaculture has emerged as the only sustainable way of supplying the rising population with fish. However the rapid expansion of aquaculture has been met with growing concerns over its environmental effects especially waste produced from aquaculture. The net cage system that is currently being used by small scale trout farmers in the Western Cape is an open water based system where release of waste into the water bodies is inevitable and this put into question the long term sustainability of trout farming using net cages in irrigation dams in the Western Cape. This study sought to compare identified production techniques that can be used by aquaculture farmers to reduce accumulation of organic waste in irrigation dams. The proposed ‘clean’ production techniques include use of net cages fitted with Lift-up system, semi intensive floating tank system (SIFTS) and intergrated aquaculture systems. The study revealed that the intergrated aquaculture system is the most effective way of recovering waste that shows great potential of moving aquaculture towards long term sustainability as it fullfills sustainability dimensions such as ‘zero emission’, nutrient recycling and integrated production. Mechanical methods of recovering waste such as Lift-up system and SIFTS are also effective in recovering particulate waste but however dissolved nutrients are lost into the environment. The study went on further to investigate if economic, environmental and social benefits of recovering waste from irrigation dams outweigh the costs of recovering waste using different production techniques. Models of small scale aquaculture farms using the three identified production techniques were developed and compared with a modelled small scale net cage farm where there was no waste recovery. A comparative financial analysis of the modelled small scale trout farms using alternative production techniques carried out showed that trout production using any of the three alternative ‘clean’ production techniques is financially viable with the SIFTS production technique giving the farmer the highest returns, followed by the intergrated system, then the net cage with a Lift-up system and lastly the net cage system without waste recovery. The second part of the study used the contingent valuation method to estimate the environmental and social benefits of removing waste from dams. Households revealed that they were willing to pay (WTP) R40 on average annually to improve water quality from a state where eutrophication had occurred to a state suitable for irrigation and aquaculture. To improve water quality from a state suitable for irrigation to a state suitable for swimming, households were willing to pay R16.67 annually. If water was to be improved from a state suitable for irrigation to a level suitable for domestic purposes, average willingness to pay (WTP) was R26.17 annually. WTP indicate that besides financial benefits associated with using ‘clean’ production techniques there are environmental and social benefits that will arise to the farm community using water from the irrigation dams. / AFRIKAANSE OPSOMMING: Die stygende vraag na vis as gevolg van bevolkingsgroei, tesame met die stagnering van die aanbod van vis vanaf natuurlike vangste het daartoe aanleiding gegee dat die oë van die wêreld op akwakultuur gerig is om die gaping in die voorsiening van vis te vul. Akwakultuur het ontwikkel as die enigste volhoubare manier om aan die groeiende vraag na vis te voldoen. Die vinnige uitbreiding van akwakultuur het egter toenemende besorgdheid in die nadelige omgewingsimpak, veral ten opsigte van akwakultuurafval, tot gevolg gehad. Die nethokstelsel wat tans deur kleinskaalse forelboere in die Wes-Kaap in oop watergebaseerde sisteme gebruik word en die vrystelling van afval in die wateromgewings wat onafwendbaar is, plaas ’n vraagteken oor die langtermyn volhoubaarheid van die nethokstelsel forelboerdery in besproeiingsdamme in die Wes- Kaap. Die studie het ten doel gehad om geïdentifiseerde produksiestelsels wat deur akwakultuurboere gebruik kan word om die akkummulasie van organiese afval in besproeiingsdamme te verminder, te vergelyk. Die voorgestelde “skoon” produksietegnieke sluit in nethokke wat aan ’n opligstelsel gekoppel word, ‘n semi-intensiewe drywende tenk- stelsel (“SIFTS system” in Engels) en ‘n geïntegreerde akwakultuurstelsel. Met hierdie studie is bevind dat die geïntegreerde stelsel die mees effektiewe manier is om afval te herwin en toon potensiaal om akwakultuur op ’n vohoubare pad te plaas aangesien dit aan die volhoubaarheidsdimensies van geen emissie, voedingstofherwinning en geïntegreerde produksie voldoen. Meganiese metodes van afvalherwinning soos die nethokopligstelsel en die SIFTS-stelsel is effektief in die herwinning van vastestofdeeltjies, maar opgeloste voedingstowwe word steeds in die omgewing vrygestel. Die studie het voorts ten doel gehad om te bepaal of die ekonomiese, omgewings- en sosiale voordele om afval uit besproeiingsdamme te herwin, groter is as die herwinningskoste van die verskillende produksietegnieke. Modelle van kleinskaalse akwakultuurplase wat die drie geïdentifiseerde produksiestelsels gebruik, is ontwikkel en aangewend om te vergelyk met ’n nethokstelsel waar geen afvalherwinning gedoen word nie. ’n Vergelykende finansiële ontleding van die gemodelleerde kleinskaalse forelboerderye met die verskillende produksietegnieke is gedoen en daar is bevind dat enige een van die drie “skoon” stelsels finansieel lewensvatbaar is, met die SIFTS-stelsel wat die hoogste vergoeding aan die boer bied, gevolg deur die geïntegreerde stelsel, dan die nethokke aan ’n opligstelsel en dan die nethokstelsel sonder afvalherwinning. Die tweede deel van die studie het van die voorwaardelike (“contingent”) waardasiemetode gebruik gemaak om die omgewings- en sosiale voordele om afval uit besproeiingsdamme te verwyder, te bepaal. Huishoudings het aangetoon dat hulle bereid sou wees om tot R40 per jaar te betaal om die waterkwaliteit te verbeter vanaf ’n toestand waar eutrifikasie plaasgevind het na ’n toestand waar die water vir besproeiing en akwakultuur geskik sou wees. Om die waterkwaliteit vanaf ’n toestand geskik vir besproeiing te verander na ’n toestand geskik om in te swem, sou huishoudings bereid wees om R16.67 per jaar te betaal. Indien water vanaf ’n toestand geskik vir besproeiing verander sou word na ’n toestand geskik vir huishoudelike gebruik, sou huishoudings gewillig wees om jaarliks R26.17 te betaal. Die “gewilligheid om te betaal” dui aan dat daar bo en behalwe die finansiële voordele om van “skoon” produksietegnieke gebruik te maak, ook omgewings- en sosiale voordele vir die plaasgemeenskap bestaan met die gebruik van die water uit die besproeiingsdamme.
123

Ecological food sense : connections between food waste flows and food production in Enkanini Informal Settlement, Stellenbosch

Mollatt, Michelle Claire 04 1900 (has links)
Thesis (MPhil)--Stellenbosch University, 2014 / ENGLISH ABSTRACT: In situ Informal Settlement Upgrading (ISU) was explored in this thesis, focussing on its relevance to waste service upgrading options immediately available and practically implementable for residents of Enkanini, a poorly serviced township (slum) in Stellenbosch, South Africa. Household food waste (kitchen scraps) was chosen as a key point of entry for exploring the context and viability of in situ improvement of solid waste management services in the area. This was done by investigating ways biological and social aspects of soil quality and food waste management can be incrementally improved in the settlement. Transdisciplinary methodology, Participatory Action Learning and Social Learning perspectives, combined with ecological thinking were used to explore different methods of managing food waste in Enkanini. A food waste collection pilot project was initiated in Enkanini by the Stellenbosch Municipality in 2012. The project was modified and continued in 2013, which served as the case study for this thesis. In 2013, food waste was collected by 56 households over five months. It was treated with Bokashi Effective Micro-organisms (Bokashi EM) containing yeasts, lactic acid bacteria, actinomycetes and photosynthetic bacteria. The Bokashi EM partially fermented the waste before it was used for composting or feeding to Black Soldier Fly (Hermetia illucens) larvae. Laboratory testing of food waste, compost, soils and larvae waste residue determined the safety, potential and sustainability of food waste for recycling and contribution to local urban agriculture by closing the organic waste loop, and for generating an income stream. A total of 5851kg food waste was collected, saving 6m3 landfill space. Households generated 5,2kg - 9,6kg food waste per week. Extrapolating this lower figure for all of Enkanini (about 2400 households), about 50,2 tonnes of food waste could be generated per month. If this were collected and recycled or composted, this would save 51,2m3 landfill space per month. The most commonly cited benefit of food waste collections by participants was reduction of vermin in or around their homes. Laboratory testing indicated that some samples had high levels of Escherichia coli (E. coli) bacteria. No traces of Salmonella were found in food waste, compost and soil samples, and most were within acceptable limits for heavy metals. It was cautioned that vegetables grown on soils or compost with high E. coli be washed or cooked before consumption. Following socially and ecologically sustainable management of Enkanini’s food waste requires a combination of waste management methods. Options include localised composting - burying EM treated food waste in soil; in situ container composting of waste and adding this to soil; processing of EM treated food waste by Black Soldier Fly larvae (and their subsequent use as feed for chickens or fish); and finally by anaerobic digestion for generation of biogas and effluent fertiliser in local biodigestors. The thesis showed that biological elements (such as bacteria and soil nutrients) have impacts on residents in communities and these need to be considered significant. The thesis suggests ecological elements be considered as indicators or building blocks for ISU locally, nationally and internationally. Keywords: in situ incremental upgrading, food waste management, Effective Micro-organisms, social learning, urban agriculture, closed-loop systems, organic waste management, informal settlements. / AFRIKAANSE OPSOMMING: In situ Opgraderingsprojek vir Informele Nedersetting (OIN) is in hierdie tesis ondersoek, met die fokus om die relevansie van afval diens opgradering opsies prakties te implementeer vir die inwoners van Enkanini, Stellenbosch, Suid Afrika, 'n gemeenskap met swak dienslewering. Huishoudelike kombuis voedselafval is gekies om die konteks en lewensvatbaarheid van in situ verbetering van vaste afval bestuur dienste te ondersoek. Dit is bereik deur maniere te ondersoek om die biologiese en sosiale aspekte van die kwaliteit van grond en voedselafval bestuur in die nedersetting te verbeter. Transdissiplinêre metode, Deelnemende Aksie Leer en Sosiale Leerprosesse, gekombineer met ekologiese denke, is gebruik is om verskillende metodes van die bestuur van voedselafval in Enkanini te verken. 'N Enkanini voedselafval versamelingsprojek is in 2012 deur die Stellenbosch Munisipaliteit begin. Dit is in 2013 aangepas en vir hierdie studie gebruik. Gedurende vyf maande in 2013 is voedselafval deur 56 huishoudings ingesamel. Dit is behandel met Bokashi effektiewe mikro-organismes (EM Bokashi) met gis, melksuur bakterieë, aktinomisete en fotosintetiese bakterieë. Die Bokashi EM het die afval gedeeltelik gegis voordat die afval gebruik was vir kompos of voeding aan Swart Soldaat Vlieg (Hermetia illucens) larwes. Voedselafval, kompos, grond en larwe oorskot laboratourim toetse het die veiligheid bepaal, asook die potensiaal en volhoubaarheid van die afval vir herwinning en die bydrae tot die plaaslike stedelike landbou deur middel van die organiese afval siklus, en vir inkomste generering. 5851kg voedselafval is ingesamel en 6m³ se opvullingsruimte bespaar. Die huishoudings het 5,2kg – 9,6kg voedselafval per week gegenereer. Die laer syfer in aggeneem, kan sowat 50,2 ton voedsalafval per maand in Enkanini (ongeveer 2400 huishoudings) gegenereer word. As dit ingesamel, herwin of gekomposteer was, sou 51,2 m³ opvullingsruimte per maand bespaar word. Die belangrikste voordeel van die voedselafval versamelings was die vermindering van knaag en aasdiere rondom wonings. Laboratoriumtoetse het hoë vlakke van Escherichia coli (E. coli) bakterieë in sommige monsters gevind. Geen spore van Salmonella is in die voedselafval, kompos en grondmonsters gevind nie en meeste was binne die aanvaarbare perke vir swaar metale. Die gemeenskap is gewaarsku om groente wat in die grond of kompos gekweek is voor verbruik in chloorwater te was of kook. Die sosiale en ekologies volhoubare bestuur van Enkanini se voedselafval vereis 'n kombinasie van afval bestuursmetodes. Opsies sluit gelokaliseerde kompos - begrawe EM behandelde voedsel afval in die grond; in situ houer kompos afval en die toevoeging van hierdie tot die grond; verwerking van EM behandelde voedselafval deur Swart Soldaat Vlieg larwes (en hul daaropvolgende gebruik as voer vir hoenders of vis); en uiteindelik deur mestvergisting vir die generasie van biogas en kunsmis in biovergisters. Die tesis toon dat biologiese elemente (soos bakterieë en voedingstowwe in grond)'n impak het op die gemeenskap se inwoners en as n belangrik faktor beskou moet word. Die tesis dui ekologiese elemente as n toekomstige aanwysers aan indien OIN plaaslik, nasionaal of internasionaal oorweeg word. Sleutelwoorde: in situ toenemende opgradering, kos afval bestuur, effektiewe mikro-organismes, sosiale leerproses, stedelike landbou, geslotestelsel-sisteme, organiese afval, informele nedersettings.
124

Impact of fly specific bacteria on fly larvae composting / Flugspecifika bakteriers inverkan på fluglarvskompostering

Lundgren, Kristina January 2019 (has links)
About one third of all edible food is wasted globally each year. This calls for improvements in resource and waste management. An interesting solution for organic waste is fly larvae composting, which both produces protein in the form of larvae and a nutrient rich residue. The larvae can be used as animal feed while the residue can be applied as an organic fertilizer, thus recycling the nutrients. Fly larvae composting with the black soldier fly (BSF), Hermetia illucens, is relatively new, but there is extensive research on how the treatment is affected by different parameters, e.g. temperature, moisture and type of organic waste that is treated. The role of bacteria has only been the topic of a few studies in recent years but has shown promising positive effects on larval growth. This study investigated the impact of bacteria isolated from BSF eggs on fly larvae composting of food waste by BSF larvae. The study was done in two experimental phases. In phase I, groups of three bacteria were added to each treatment together with the larvae and only single treatments were executed; in phase II triplicates of promising groups of three, two or single bacteria were evaluated. The results of phase I suggested that selected groupings of bacteria could either decrease or increase the bioconversion ratio and in general decrease the reduction ratio of the food waste, while the survival ratio did not seem to be impacted. However, in phase II no significant difference (p<0.05) between the treatments with bacteria and the control were found for any evaluated variables. Interestingly, the variation in resulting bioconversion ratio and reduction ratio (on a VS basis) was found to be reduced when one or more bacteria were present. The coefficient of variation in bioconversion ratio was 9.5% for the control compared to between 2.5% and 6.1% for treatments with bacteria. For the reduction ratio the variation was reduced from 5.6% and to between 0.9% and 4.6% for the bacteria treatments. Hence, seeding with bacteria may improve stability of the process, which is especially interesting when scaling up the process. / Globalt slängs ungefär en tredjedel av all ätbar mat. Därmed finns ett stort behov av säker och hållbar avfallshantering. En intressant lösning för organiskt avfall är fluglarvskompostering, som både producerar protein i form av larver och en näringsrik behandlingsrest. Larverna kan exempelvis användas som djurfoder medan behandlings-resten kan användas som gödselmedel, vilket innebär att näring kan återvinnas. Fluglarvskompostering med amerikansk vapenfluga (BSF), Hermetia illucens, är en relativt ny teknik men det finns redan omfattande forskning på hur olika processparametrar, t.ex. temperatur och vattenhalt, påverkar processen. Bakteriers roll har studerats endast i ett fåtal studier men de indikerar att tillsats av bakterier kan ha en positiv inverkan på larvernas tillväxt. Den här studien har därför undersökt hur tillsats av bakterier isolerade från BSF ägg påverkar fluglarvskompostering av matavfall med BSF larver. Studien gjordes i två experimentella delar. I fas I undersöktes effekten av tillsats av bakteriegrupper om tre bakterier till matavfallet samtidigt med larverna; i fas II utfördes triplikat av lovande bakteriegrupper med tre, två eller enstaka bakterier. Resultaten från fas I indikerade att olika bakteriegrupper antingen kunde höja eller sänka bioomvandlingskvoten och generellt gav en minskning i materialreduktions-kvoten medan överlevnadsgraden inte verkade påverkas i samma utsträckning. I fas II observerades däremot ingen signifikant skillnad (p<0,05) mellan någon av bakteriebehandlingarna och kontrollen för samtliga processvariabler. Variationen i resulterande bioomvandlingskvot och materialreduktionskvot (på VS basis) var dock lägre för bakteriebehandlingarna jämfört med kontrollen. Variationen i bioomvandlings-kvot var 9,5% för kontrollen jämfört med 2,5-6,1% för bakteriebehandlingarna. För materialreduktionskvoten minskade variationen från 5,6% till mellan 0,9% och 4,6%. Detta tyder på att tillsats av bakterier kan förbättra stabiliteten hos fluglarvskompostering, vilket är särskilt intressant vid uppskalning av processen.
125

Die Eluate des mikrobiellen Abbaus organischer Massen in ihrer chemischen Zusammensetzung und ihrer Kopplung mit freigesetzten Asche-Anteilen / The eluates of the microbial degradation of organic masses in their chemical composition and its coupling with released ash portions

Hofmann, Heidrun 03 February 2005 (has links)
No description available.
126

Modélisation des flux de biomasse et de nutriments dans les territoires agricoles : simulation et évaluation de scénarios appliqués à un cas d’étude en France / Modelling biomass and nutrient flows in agro-food systems at the local scale : scenario simulation and assessment in a French case-study

Fernandez mena, Hugo 19 December 2017 (has links)
Nourrir une population mondiale croissante dans un contexte de changements globaux pose de nouveaux défis à l’agriculture en termes d’efficience de production et d’impacts environnementaux. Rendre les systèmes agro-alimentaires plus soutenables nécessite de mieux recycler la biomasse et les nutriments, c’est-à-dire de tendre vers des flux de fertilisants, de produits végétaux, d’aliments du bétail, de coproduits et de déchets plus circulaires. À ce titre, il est nécessaire de développer de nouveaux outils pour mieux explorer et évaluer les échanges de matières entre les fermes et leurs partenaires économiques amont et aval dans les territoires. Dans le travail présent, l’état de l’art concernant les méthodes d’analyse, de modélisation et d’évaluation environnementale des flux de biomasse et d’éléments minéraux à différentes échelles est réalisé. Le modèle multi-agents FAN (« Flows in Agricultural Network») qui simule les flux des matières entre les fermes et leurs partenaires économiques dans les territoires agricoles a été développé. Les processus de FAN sont expliqués en détail et une analyse de sensibilité des variables clefs est présentée. Par ailleurs, le modèle FAN a été appliqué à un cas d’études en France pour évaluer la performance des scénarios contrastés visant à améliorer l’efficience d’utilisation des éléments minéraux, développer le recyclage de la matière, favoriser la production du biogaz ou reconcevoir les systèmes de production. Les sorties de simulations des scénarios sont analysées en termes de production alimentaire et énergétique, de flux de matières et de logistique, de cycle des nutriments et d’émissions de gaz à effet de serre. Ce travail montre l’utilité des outils de prospective et modèles multi-agents pour améliorer la durabilité des systèmes agricoles et des chaines alimentaires, pour créer et évaluer des solutions collectives tendant vers l’économie circulaire et pour prendre en charge les interactions entre acteurs économiques au sein des chaines et filières alimentaires complexes. / Feeding the growing global population in a context of global change raises new challenges for agriculture regarding its production efficiency and impacts on natural resources. Solutions for towards farming sustainability require to improve nutrient and biomass recycling in agro-food systems, i.e. to move from linear to more circular flows of fertilizers, crop products, feedstuff, by-products and organic wastes. Innovative tools exploring material exchanges between farms and their upstream and downstream partners in agro-food systems at the local scale are needed. In the present work, the state of the art about analysis methods, models and environmental tools addressing nutrient and biomass flows at different scales is reviewed. The FAN (“Flows in Agricultural Network”) model, an agent-based model that simulates a range of material flows among farms and their partners within agricultural districts is developed. FAN processes are explained in details and a sensitivity analysis to some key variables is performed. In addition, the FAN model is applied to a French case-study to assess the performances of contrasted scenarios aiming to enhance nutrient use efficiency, recycling strategies, biogas production and system redesign. The outcomes from the scenario simulation are analyzed are assessed in terms of food provisioning, nutrient cycling and greenhouse gas emissions. This work shows the usefulness of prospective, agent-based tools for greater farming and food-chain sustainability, to design and evaluate collective solutions for circular economy and to account for interactions among economic actors within complex agro-food systems.
127

Determinação do gradiente de pressão estática do ar para sistemas de compostagem por aeração forçada / Determination of static pressure gradient of air for composting system by forced aeration

Teixeira, Denis Leocádio 18 July 2014 (has links)
Made available in DSpace on 2015-03-26T13:23:59Z (GMT). No. of bitstreams: 1 texto completo.pdf: 1263079 bytes, checksum: 4f8dcc7d9121a93cc4f882cd8390c608 (MD5) Previous issue date: 2014-07-18 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Although there equations and graphics in scientific literature to estimate the static pressure gradient of airflow through layers of grains and seeds, studies using organic waste submitted to composting treatment are scarce. The objective of this study was to adjust equations to estimate the static pressure gradient of airflow through layers of different organic residues. The waste used were chicken litter and as bulking agents and carbon source: sugarcane bagasse, sawdust and coffee husk which were mixed in the ratio of 0; 10; 20; 30 e 40% (volumetric basis), of chicken litter in relation to bulking agents, as well as mixture with C/N ratio of 25/1, which were submitted to composting process. Measurements of static pressure drop in layers of organic waste before and after the composting process, and in layers of material from the different proportions of chicken litter added to bulking agents, were performed using a prototype with specific airflow rates ranging from 0.02 to 0.13 m 3 s -1 m -2. The static pressure drop of airflow increased as a power of the material layer thickness. Static pressure gradient in layers of organic waste decrease with the composting process. Shedd, Hukill & Ives and Hunter models may be used to predict the static pressure gradient of air to be blown through the organic residues layers, however, the Shedd model was that which best represented the phenomenon studied. Lower values of static pressure gradient were obtained in layers without chicken litter and the higher values obtained in layers composed of mixture of chicken litter in proportion of 40%. Equations to estimate the static pressure gradient for different proportions of chicken litter may be clustered, yielding models that can explain the variation of pressure gradient for each bulking agent and carbon source. / Embora existam, na literatura científica, equações e gráficos para estimativa do gradiente de pressão estática do ar, quando forçado em camadas de grãos e sementes, são poucos os trabalhos realizados utilizando-se resíduos orgânicos submetidos ao tratamento por compostagem. Neste trabalho, teve-se por objetivo o ajuste de equações que possibilitassem a estimativa do gradiente de pressão estática do ar, quando insuflado em camadas de diferentes materiais orgânicos. Os resíduos utilizados foram a cama de frango e, como agentes estruturantes e fonte de carbono, o bagaço de cana-de-açúcar, a serragem de madeira e a palha de café, os quais foram misturados nas proporções de 0; 10; 20; 30 e 40% (base volumétrica) de cama de frango em relação aos agentes estruturantes, além de misturas com relação C/N de 25/1, as quais foram submetidas ao tratamento por compostagem. As medições da queda de pressão estática do ar, ao atravessar camadas de material orgânico, antes e depois de ter sido submetido ao tratamento por compostagem, e nas camadas de materiais provenientes das diferentes proporções de cama de frango adicionada aos agentes estruturantes, foram realizadas utilizando-se um protótipo, no qual o material foi submetido a vazões específicas de ar que variaram de 0,02 a 0,13 m 3 s -1 m -2 . A queda na pressão estática do ar aumentou de forma potencial com a espessura da camada de material. No que se refere ao decurso do processo de compostagem, este contribuiu para redução do gradiente de pressão estática do ar ao atravessar as camadas de material orgânico. Os modelos matemáticos de Shedd, Hukill & Ives e Hunter podem ser utilizados para predizer o gradiente de pressão estática do ar, ao ser insuflado em camadas de resíduos orgânicos, no entanto, o modelo de Shedd pode ser considerado, em termos estatísticos, o que melhor representou o fenômeno em estudo. Menores valores de gradientes de pressão estática do ar foram obtidos em camadas sem adição de cama de frango e os maiores obtidos nas camadas constituídas pela mistura com cama de frango na proporção de 40%. As equações obtidas para estimativa do gradiente de pressão estática do ar, para as diferentes proporções de cama de frango, podem ser agrupadas, originando modelos capazes de explicar a variação do gradiente de pressão para cada agente estruturante e fonte de carbono.
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Desenvolvendo e gerenciando compostagem de res?duos s?lidos urbanos: para gera??o de renda e repasse de tecnologia ? acrevi

Sousa J?nior, Francisco Souto de 11 July 2011 (has links)
Made available in DSpace on 2015-03-03T15:43:02Z (GMT). No. of bitstreams: 1 FranciscoSSJ_DISSERT.pdf: 1787707 bytes, checksum: 43dde43d6a3eb1e5d3dd4888ccb3c5b4 (MD5) Previous issue date: 2011-07-11 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / Nowadays, as well as in the past decades, the dumping of biodegradable organic waste in landfill is common practice in Brazil, as well as in most parts of the world. Nevertheless due to its rapid decomposition and release of odors, this practice hamper?s the operation and implementation of a recycling system. These facts encouraged our research to find an efficient system for the management of organic waste, not only for the use of official workers responsible for managing these wastes, but also for non-governmental institutions. The Recycling for Life Community Association ? ACREVI (Associa??o Comunit?ria Reciclando para a Vida), together with the municipal authorities of Mossor?-RN, Brazil, have assumed the social role of collecting and recycling solid waste produced by most of the local population. However, it was observed that the organic waste it collected was not receiving any treatment. This present work aims to make compost with mixed waste (green waste and organic household), and then do chemical analysis of the material in view to use the waste as organic fertilizer. The objective being: to share the knowledge acquired by putting it into a very simple language accessible to people with little education. The experiment was conducted at ACREVI, Mossor? (RN), and the compost was obtained following the method "windrow", forming three cells (I, II, III) with conical shape, dimensions of 1.6 meters and 2.0 meters in diameter for cells I and II, and 1.0 meters high and 2.0 meters in diameter for cell III. The process was accompanied by analysis: CHN elemental, a variation of cell temperature, humidity, pH, TKN, bulk density, nutrients and heavy metals. Stabilized organic compounds reached the C/N ratio of 10.4/1 cell I and 10.4/1 in the cell II in the cell, showing how good soil conditions, with potential to improve the physical properties of any soil and pH acid soils, has presented the cell III at the end of the process the C/N 26/1, is a high ratio may be associated with the stack size III, thus changing the optimal conditions for the occurrence of the process. The levels of heavy metals in the analyzed compounds were lower than those established by the SDA normative instruction, N? 27, of 5 June, 2006. The use of pruning trees and grass are used in small-scale composting, while generating a quality compost in the final process, it also created an important condition for a correct sizing of the composting piles. Under the studied conditions it is not advisable to use cells with a height of 1.00 m in height and 2.00 m in diameter, as these do not prevent the rapid dissipation of heat and thus can not be a good product at the end of composting. The composting process in the shed of the association and the preparation of the primer enabled the development of an alternative technology to generate income for members of ACREVI. / Durante d?cadas e ainda hoje no Brasil, assim como em muitos pa?ses do mundo a deposi??o de res?duos org?nicos biodegrad?veis em aterro foi uma pr?tica muito comum, pois a r?pida decomposi??o e a libera??o de odores destes res?duos dificultam a operacionaliza??o e aplica??o de um sistema de reciclagem. Estes fatos incentivam ? busca de medidas eficientes para a gest?o de res?duos org?nicos n?o s? nas entidades oficiais respons?veis pela gest?o destes res?duos, mas tamb?m nas institui??es n?o governamentais. A Associa??o Comunit?ria Reciclando para a Vida ACREVI, com o apoio da prefeitura municipal de Mossor?, Brasil, tem assumido o papel social da coleta e reciclagem de res?duos s?lidos produzido por grande parte da popula??o local. Por?m, observou-se que os res?duos org?nicos que ela coleta n?o est?o recebendo qualquer tratamento. Nesse trabalho objetivou-se realizar a compostagem com misturas de res?duos urbanos (res?duos verdes e org?nicos domiciliares), fazer a an?lise qu?mica desse material, tendo em vista sua utiliza??o como adubo org?nico, e repassar o conhecimento produzido em linguagem bem simples e acess?vel a pessoas com baixa escolaridade via produ??o de uma cartilha de compostagem. O experimento foi realizado na ACREVI, Mossor? (RN) e o produto da compostagem foi obtido seguindo o m?todo windrow , formando tr?s pilhas (I, II, III) com formato c?nico, dimens?es de 1,6 metros de altura e 2,0 metros de di?metro para as pilhas I e II, e 1,0 metro de altura e 2,0 metros de di?metro para a pilha III. O processo foi acompanhado atrav?s das an?lises: elementar de CHN, varia??o de temperatura da pilha, grau de umidade, pH, NTK, densidade aparente, metais pesados e nutrientes. Os compostos org?nicos estabilizados atingiram a rela??o C/N de 10,4/1 na pilha I e 10,4/1 na pilha II, mostrando-se como bons condicionantes de solo, apresentando potencial para melhorar as propriedades f?sicas de qualquer solo e o pH de solos ?cidos, j? a pilha III apresentou no final do processo rela??o C/N 26/1, est? alta rela??o pode ser associada ao tamanho da pilha III, alterando desta forma as condi??es ideais para ocorr?ncia do processo. Os teores de metais pesados analisados nos compostos foram inferiores aos estabelecidos pela instru??o normativa SDA, N? 27 de 05 de Junho de 2006. O uso de podas de arvores e gramas, utilizadas na compostagem em pequena escala, ao mesmo tempo em que gerou um composto de qualidade no produto final do processo, tamb?m criou uma condi??o importante para um correto dimensionamento das pilhas de compostagem. Nas condi??es estudadas n?o ? aconselh?vel utilizar pilhas com altura de 1,00 m de altura e 2,00 m de di?metro, pois estas n?o impedem a r?pida dissipa??o de calor e assim n?o se consegue um bom produto no final da compostagem. O processo de compostagem no galp?o da associa??o e a elabora??o da cartilha viabilizou o desenvolvimento de uma tecnologia alternativa de gera??o de renda para os associados da ACREVI
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Uso de resíduo da extração de celulose e o impacto em solo de cerrado cultivado com eucalipto e espécie arbórea nativa /

Arruda, Otton Garcia de. January 2012 (has links)
Orientador: Marlene Cristina Alves / Banca: Francisco Maximino Fernandes / Banca: Rafael Montanari / Resumo: Com a produção de papel e celulose as indústrias do setor têm gerado diariamente grandes quantidades de resíduos sólidos e efluentes, constituindo-se em uma grande preocupação ambiental e econômica. No intuito de retornar com estes subprodutos de forma sustentável à natureza, esse trabalho teve como objetivo testar a eficácia de um resíduo orgânico advindo da indústria de papel e celulose quanto a sua influência sobre os atributos químicos e físicos do solo e desenvolvimento de plantas arbóreas. O experimento foi implantado em um Latossolo Vermelho distrófico no município de Selvíria, MS. O delineamento experimental foi em blocos ao acaso, onde se avaliou o clone Eucalyptus spp. e a espécie nativa Mabea fistulifera com cinco tratamentos: sem adubação (controle), adubação mineral, 10 t ha -1, 15 t ha-1 e 20 t ha-1 do resíduo celulósico. Nas camadas de solo de 0-0,05; 0,05-0,10; 0,10-0,20 e 0,20-0,40 m avaliaram-se os atributos químicos: MO, pH, P, K, Ca, Mg, H + Al, Al e calculou-se a SB, CTC e V%; e os atributos físicos: macroporosidade, microporosidade, porosidade total, densidade do solo, estabilidade de agregados em água, resistência do solo à penetração e infiltração de água. Para as características dendrométricas das plantas foram avaliados: altura média de plantas, diâmetro do caule na superfície do solo (DSS) e diâmetro médio das copas (DMC) trimensalmente, até os 21 meses. Para a cultura do eucalipto, também foram determinados o diâmetro a altura do peito (DAP), o volume de madeira e o incremento médio anual do volume de madeira aos 21 meses. Os resultados foram analisados aplicando-se a comparação entre médias, contrastes e análise de regressão. Concluiu-se que o uso de resíduo celulósico influenciou os atributos do solo estudado, principalmente nas camadas superficiais do solo... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: A large amount of solid waste and effluents have been daily generated by industries due to the cellulose and paper production, becoming a major environmental and economic concern. In order to return with these by-products in a sustainable way to nature, the aim of this study was to test the effectiveness of an organic waste from cellulose and paper industry as its influence on soil chemical attributes and development of eucalyptus plants. The experiment was implanted in an Oxisol in the city of Selvíria, MS, Brazil. A randomized block design was used, which evaluated Eucalyptus spp. and and the native species Mabea fistulifera with five treatments: no fertilization (control), mineral fertilizers, 10 t ha -1, 15 t ha-1 and 20 t ha-1 of cellulosic residue. In the soil layers of 0-0,05; 0,05-0,10; 0,10 - 0,20 and 0,20 - 0,40 m, were evaluated: organic matter, pH, P, K, Ca, Mg, H+AL, Al and calculated the sum of bases, CEC and base saturation, and physical attributes: macroporosity, microporosity, total porosity, bulk density, aggregate stability in water, soil resistance to penetration and water infiltration. For the plants dendrometric characteristics were evaluated: plant height, stem diameter at the soil surface and diameter of the crown quarterly, up to 21 months. For the cultivation of eucalyptus the diameter at breast height, the volume of wood and the average of the annual increment of timber volume were also determined. The results were analyzed by comparison of means, contrasts and regression analysis. In conclusion, the use of cellulosic waste influence the soil characteristics studied mainly in the surface layers of soil (0-0,10 m), negatively macroporosity and infiltration of water to the cultivation of eucalyptus and stabilit y of aggregates M. fistulifera. For the chemical increased the contents of Ca, Mg, SB and CEC of the soil for eucalyptus... (Complete abstract click electronic acces / Mestre
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Diseño de modelo de la cadena de suministro del fertilizante orgánico para reutilizar desechos orgánicos y aumentar el consumo de fertilizantes en el Perú / Design of a model eco-friendly fertilizer supply chain to reuse organic waste and increase consumption of fertilizers in Peru

Flores Yaranga, Andrea Luz, Vasquez Perez, Renzo Alberto 22 November 2020 (has links)
Durante muchos años, el consumo global de fertilizantes ha mostrado una tendencia positiva, que también se refleja en el sector agrícola peruano. Sin embargo, en Perú el consumo de fertilizantes en kilogramos por hectárea agrícola es muy bajo en comparación con los países de América del Sur, ya que se consumen alrededor de 128 kilogramos por hectárea, cuando la recomendación de la Organización de las Naciones Unidas para la Agricultura y la Alimentación es de aproximadamente 204 kilogramos por hectárea. hectárea agrícola. Por ello, este problema fue analizado en el contexto del mercado agrícola peruano para determinar las posibles causas raíz, que ayudarían a incrementar el consumo de fertilizantes en el Perú. Se determinó que este problema es causado principalmente por el comercio centralizado de fertilizantes en el departamento de Lima y por la baja importación anual de fertilizantes orgánicos, que impactan directamente en la baja disponibilidad de fertilizantes orgánicos. Por ello, este artículo propone un modelo de cadena de suministro de fertilizantes ecológicos a través de la metodología SCOR para emplear la mejor solución posible que abarque todas las incertidumbres de la disponibilidad de fertilizantes orgánicos en el Perú. Este modelo identificará una mejora en los costos operativos y la rentabilidad para las partes interesadas en esta cadena de suministro. Como resultado final, el proyecta presenta una mejora en la sustentabilidad, la cual se incrementó en 2.8 y sostenibilidad, cuya mejora se incrementó en 3.2 con respecto a la situación actual de la cadena de suministro del floculo. / For many years, the global consumption of fertilizers has shown a positive trend, which is also reflected in the Peruvian agricultural sector. However, in Peru the consumption of fertilizers in kilograms per agricultural hectare is very low compared to the countries of South America, since around 128 kilograms per hectare is consumed, when the recommendation of the United Nations Organization to Agriculture and Food is approximately 204 kilograms per agricultural hectare. For this reason, this problem was analyzed in the context of the Peruvian agricultural market to determine the possible root causes, which would help to increase the consumption of fertilizers in Peru. It was determined that this problem is caused mainly by the centralized trade of fertilizers in the department of Lima and by the low annual import of organic fertilizers, which directly impact on the low availability of organic fertilizers. For this reason, this article proposes a supply chain model for eco-friendly fertilizer through the SCOR methodology to employ the best possible solution that encompasses all the uncertainties of the availability of organic fertilizers in Peru. This model will identify an improvement in operating costs and profitability for stakeholders in this supply chain. As a result, an economic acceptance of the project is obtained since in this case 4 financial indicators were used to determine the economic viability of the project. As a final result, the project presents an improvement in sustainability, which increased by 2.8 and sustainability, whose improvement was increased by 3.2 with respect to the current situation of the floc supply chain. / Trabajo de investigación

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