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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.
301

Utilização de agregados de RCC e resíduo de polimento de placas cimentícias em artefatos de concreto / Use of CDW aggregates and cementitious slab polishing residue in concrete artifacts

Leviski, Anderson 20 December 2016 (has links)
A Construção Civil é um dos setores que mais consomem matérias-primas e também gera resíduos sólidos urbanos. É importante, que se consuma menos matérias-primas e que sejam aproveitados estes resíduos gerados. Uma das propostas para esta situação seria reciclar estes resíduos e transformá-los em agregados e filers, para então usá-los na produção de concretos. Ainda se encontram muitas barreiras para utilização destes agregados e filers em concretos, com e sem função estrutural e, dentre os principais motivos está a dificuldade de se alcançar resistências similares as dos concretos produzidos com matérias-primas naturais. Devido a este fato, foi proposto um estudo para analisar a influência do empacotamento de partículas nos agregados reciclados e ainda verificar a possibilidade de uso do filer de pó do polimento das placas de concreto para revestimento de piso. Inicialmente foram caracterizados dois lotes de agregados reciclados e apenas o de resíduo de concreto (ARC) foi considerado adequado para o estudo. Foram propostos três planejamentos experimentais compostos por mistura simplex com 4 fatores das misturas, contendo além dos agregados, filer e cimento Portland CP-V. Foram realizados estudos sobre as massas unitárias das amostras, para cada um dos planejamentos, considerando toda a faixa granulométrica, e também, amostras sem o material passante pela peneira com abertura de 0,150 mm. A quantidade de água foi determinada pelo consistômetro de Vebe, e a partir deste dado foi calculado o excesso de pasta. Após a obtenção dos corpos de prova, sob vibrocompactação, foi determinado o comportamento da resistência mecânica e da absorção de água. A análise dos resultados mostrou que o melhor empacotamento de partículas dos agregados ocorre na faixa de 42% a 58% de pedrisco. O filer utilizado em grandes quantidades, aumenta significativamente o consumo de água de amassamento e o de excesso de pasta, e por consequência, o aumento da absorção de água e perda de resistência do concreto seco. Entretanto, em quantidades menores que o volume de poros, a inclusão do filer é aceitável, pois não há afastamento das partículas. Conclui-se que, na faixa granulométrica estudada não houve alteração de resistência mecânica, sendo o fator preponderante a concentração de cimento. As resistências à compressão observadas mostram que estes agregados podem ser utilizados na fabricação de artefatos de concreto, como por exemplo, produção de blocos de vedação. / Civil Construction is one of the sectors that consumes the rawest materials and also generates municipal solid waste. It is important that less raw materials are consumed and that waste generated is used. One of the proposals for this situation would be to recycle these wastes and turn them into aggregates and filers and then use them in the production of concrete. There are still many barriers to the use of these aggregates and filers in concrete, with and without structural function, and among the main reasons is the difficulty of achieving similar resistance to concrete produced with natural raw materials. Due to this fact, a study was proposed to analyze the influence of the packing of particles in the recycled aggregates and to verify the possibility of using the filter of powder of the polishing of the concrete plates for floor covering. Initially, two batches of recycled aggregates were characterized and only that of concrete residue was considered adequate for the study. Three experimental schedules were proposed, composed of 4 factors of the mixtures, plus the aggregates, filer and Portland cement CP-V. Samples were analyzed for the sample masses, considering the entire grain size range, as well as samples without material passing through the sieve with a 0.150 mm opening. The amount of water was determined by the Vebe consist meter, and from this data, the excess paste was calculated. After the test specimens were obtained, under vibrarocompaction, the behavior of the mechanical resistance and the water absorption were determined. The analysis of the results showed that the best packaging of particles of the aggregates occurs in the range of 42% to 58% of hail. The filer used in large quantities significantly increases the consumption of kneading water and excess paste, and consequently, increased water absorption and loss of strength of dry concrete. However, in smaller amounts than the pore volume, the inclusion of the filer is acceptable, since there is no separation of the particles. It was concluded that in the granulometric range studied, there was no change in mechanical strength, being the preponderant factor the concentration of cement. The observed compressive strengths show that these aggregates can be used in the manufacture of concrete artifacts, such as the production of sealing blocks.
302

Material para construção civil a partir de lodo de estação de tratamento de água, lama de polimento de mármore e resíduo de produção de cal / Construction material from water treatment sludge, marble polish mud and lime production waste

Hackbart, Fernanda Meireles 11 December 2015 (has links)
O crescimento populacional acelerado é o grande motivador para o desenvolvimento do setor da construção civil e o aumento na demanda por água potável, tendo como consequência, um aumento gradativo na geração de resíduos sólidos. Dessa forma, este trabalho foi realizado com o intuito de reciclar resíduos industriais e municipais incorporando-os em materiais para a construção civil. O compósito produzido a partir de lodo de estação de tratamento de água e lama de polimento de mármore, aplicando resíduo de produção de cal como ligante, foi avaliado quanto ao seu desempenho mecânico e sua estrutura morfológica. As matérias-primas foram caracterizadas quanto sua composição química, mineralógica,morfológica, granulométrica e, também, o teor de umidade. Com os materiais caracterizados, foram desenvolvidas nove composições variando-se o teor de lodo de estação de tratamento de água entre 25 e 50%, o teor de lama de polimento de mármore entre 35 e 50% e o resíduo de produção de cal entre 10 e 30%. Os compósitos foram submetidos a ensaios de resistência mecânica, absorção de água, análise química, mineralógica e morfológica. Os materiais desenvolvidos apresentaram, no 3° dia de cura, valor de resistência mecânica máxima de 4,65 MPa, no 7° dia 6,36 MPa, no 14° dia 6,74 MPa, no 28° dia 5,98 MPa, no 60° dia 8,52 MPa, no 90° dia 11,75 MPa e no 180° dia 12,06 MPa. Os valores de absorção de água aos 28 dias de cura variaram de 16,27 a 26,32% e aos 90 dias, de 13,57 a 23,56%. / The rapid population growth is the great motivator for the development of the construction industry and the increased demand for drinking water, resulting in a gradual increase in the generation of solid waste. Thus, this work was carried out in order to recycle industrial and municipal wastes incorporating them into materials for civil construction. The composite produced from water treatment sludge and marble polishing mud, applying lime production waste as a binder, was evaluated for its mechanical performance and its morphological structure. The raw materials were characterized for their chemical composition, mineralogy, morphology, particle size and also the moisture content. With the featured materials nine compositions have been developed varying the content of the water treatment sludge between 25 to 50%, marble polishing mud between 35 to 50% and the lime production waste between 10 to 30%. The composites were subjected to mechanical strength tests, water absorption, chemical and mineralogical composition and morphology. The developed materials presented, on the 3rd day of hydration, maximum strength value of 4.65 MPa, the 7th day 6.36 MPa, on the 14th day 6.74 MPa, the 28th day 5.98 MPa, on the 60th day 8.52 MPa at 90th day 11.75 MPa and 180th day 12.06 MPa. The water absorption values after 28 days of hydration ranged from 16.27% to 26.32% and after 90 days, from 13.57% to 23.56%.
303

Utilização de resíduos de argamassa, lodo de anodização de alumínio e cal para a formação de um novo compósito / Use of argamassa residues, anodization sludge of aluminum and lime for the formation of a new composite

Molinetti, Andréa 01 August 2016 (has links)
Os resíduos decorrentes da construção civil apresentam, na maioria das vezes, a predominância de materiais inertes e passíveis de reaproveitamento, que não tem em grande parte uma finalidade. Esta dissertação apresenta uma abordagem sobre destinação correta dos resíduos, utilizando resíduos de argamassa, lodo de anodização de alumínio e cal para a formação de um novo compósito. O maior objetivo desta dissertação é caracterizar os materiais como componentes de novos compósitos para a construção civil, além de identificar novas composições (ao todo são 13 composições) atendendo as normas e leis existentes, analisar os processos físico-químicos, determinar as propriedades mecânicas e adaptar tecnologias existentes no processo de fabricação, além de destinar sem danos ambientais todas as matérias primas. Para análises físico-químicas e mecânicas foram estudados os seguintes parâmetros: resistência uniaxial média, absorção de água, densidade aparente, retração linear, microscopia eletrônica de varredura (MEV), espectrometria por energia dispersiva, difração de raios-X e espectrometria de fluorescência de raios-X (FRX). Dentre as 13 composições foram escolhidas as composições 4 e 11 para analisar mais o comportamento físico-químico. A resistência à compressão média uniaxial, aos 90 dias da composição 11 alcançou 9,18 MPa, com coeficiente de absorção de água de 12%, a retração foi de 1,53% e a densidade ao longo de 180 dias de cura variou apenas 4%. Os estudos físico-químicos identificaram a presença de Carbono, Sódio, Magnésio, Alumínio, Silício e Cálcio na composição 11, e através do MEV e FRX foi possível identificar que se trata de uma estrutura amorfa. Através desses estudos propõe-se alternativas que sejam revertidas em vantagens sociais e ambientais, tais como a fabricação de blocos vazados de concreto simples para alvenaria sem função estrutural, blocos cerâmicos para alvenaria de vedação, tijolos maciços para a alvenaria em relação a categoria A, entre outros. / Waste from the construction, have in most cases the predominance of inerts materials and insusceptible reuse, which has a few purpose. This dissertation presents an approach on the correct disposal of this waste, using mortar residue, anodizing aluminum sludge and lime to form a new composite. The main objective of this project is to characterize the materials as components of new composites for the construction industry, and identify new compositions (they are 13 compositions) meet the existing standards and laws, analyze the physical and chemical processes, determine the mechanical properties and adapting existing technologies in the manufacturing process, beyond to appropriate correctly without environmental damage for all the materials. For physical-chemical and mechanical analysis, the following parameters were studied: resistance average uniaxial, water absorption, apparent density, linear retraction, environment-scanning electron microscopy, energy dispersive x-ray, x-ray diffraction and x-ray fluorescence. Between the 13 compositions, chosen compositions 4 and 11 to analyze the behavior. The average uniaxial compressive strength at 90 days composition 11 reached 9,18 MPa with 12% water absorption coefficient, the shrinkage was 1,53% and the density over 180 days varied only 4%. The physic-chemical studies have identified the presence of Carbon, Sodium, Magnesium, Aluminum, Silicon and Calcium in the composition 11 and about scanning electron microscopy and XRF identified that it is an amorphous structure. Through these studies, it was possible to propose alternatives that are reversed in social and environmental benefits, such as the manufacture of simple concrete hollow blocks brickwork without structural function, ceramic blocks for sealing brickworks and solid bricks for brickworks in relation to category A, among others.
304

Desenvolvimento de novos compósitos destinado a materiais de construção civil, com base em resíduos industriais de solo de decapagem, lodo e sedimentos de dragagem do porto de Antonina e cal virgem comum

Pan, Roberto Chun Yan 09 June 2015 (has links)
Pesquisa realizada para analisar o compósito de solo de decapagem (SD) considerado resíduos nas jazidas de minérios, em especial de calcário do município de Almirante Tamandaré, da Região Metropolitana de Curitiba neste trabalho, juntamente com o lodo e sedimentos de dragagem marinha do Porto de Antonina, no Estado do Paraná, e o uso cal virgem comum, como aglomerante pertencente à região de Almirante Tamandaré. Foram utilizados vários teores dos materiais para a determinação de 12 (doze) compósitos. Para o solo de decapagem os teores variaram entre 30% a 60%, para o material de dragagem os teores variaram entre 20% a 50% e o teor de aglomerante de cal virgem comum variou entre 15% a 30%. Foram moldadas idades de cura de 3 dias, 7, 14, 28, 60, 90, 180 e 365 dias. O aumento da resistência à compressão durante a cura foi proveniente das reações químicas das partículas sólidas das matérias-primas em ambiente alcalino gerando novas formações amorfas. Também foram analisados os materiais nos métodos de MEV com EDS, DRX e FRX, para a obtenção da composição química e formação estrutural dos novos compósitos. Todos os resultados da resistência à compressão uniaxial, com 28 dias de cura ao meio ambiente das 12 (doze) composições, obtiveram resultados médios de 7,7 MPa, atendendo satisfatoriamente a norma NBR 7170:1983 que determina a resistência à compressão igual ou acima de 4,0 MPa, destinada à produção de materiais de construção para alvenaria de vedação, sem fins estruturais. Comprovando o uso desses compósitos em materiais de construção civil, principalmente para os segmentos de blocos ou tijolos de vedações, sem fins estruturais, sem a necessidade de cozimento ou empreendimento de energia calorífica para a cura das peças, contribuindo para o meio ambiente e a sustentabilidade ambiental. / Research conducted to analyze the composite with pickling soil (SD), considered waste in mineral deposits, especially of limestone in the city of Almirante Tamandaré, the Metropolitan Region of Curitiba in this work, along with the sludge and marine dredging sediment from the Port of Antonina, State of Paraná, and use the common quicklime as binder belonging to the same region of Almirante Tamandaré. Various amounts of materials were used for the determination of twelve (12) composites. For the stripping soil content ranged from 30% and 60%, for the dredging material contents ranged from 20% and 50% and binder common quicklime content ranged from 15% to 30%. Were molded curing ages of 3 days, 7, 14, 28, 60, 90, 180 and 365 days. The increase in compressive strength during curing was derived from the chemical reactions of solid particles of raw materials in alkaline environment generating the new amorphous formations. Also the raw materials were analyzed in the SEM with EDS method, DRX and FRX, to obtain the chemical composition and formation structures of the new composite. All results of the uniaxial compressive strength, with 28 days of curing the environment of the twelve (12) compositions, obtained average results of 7.7 MPa, satisfactorily meeting the NBR 7170:1983 standard that determines the resistance to compression equal or above 4.0 MPa, for the production of building materials for sealing masonry without structural purposes. Proving the use of these composites in construction materials, especially for thread block or brick fences without structural purposes, without the need for cooking or heating energy project for the healing of parts, contributing to the environment and sustainability Environmental.
305

Material para construção civil a partir de lodo de estação de tratamento de água, lama de polimento de mármore e resíduo de produção de cal / Construction material from water treatment sludge, marble polish mud and lime production waste

Hackbart, Fernanda Meireles 11 December 2015 (has links)
O crescimento populacional acelerado é o grande motivador para o desenvolvimento do setor da construção civil e o aumento na demanda por água potável, tendo como consequência, um aumento gradativo na geração de resíduos sólidos. Dessa forma, este trabalho foi realizado com o intuito de reciclar resíduos industriais e municipais incorporando-os em materiais para a construção civil. O compósito produzido a partir de lodo de estação de tratamento de água e lama de polimento de mármore, aplicando resíduo de produção de cal como ligante, foi avaliado quanto ao seu desempenho mecânico e sua estrutura morfológica. As matérias-primas foram caracterizadas quanto sua composição química, mineralógica,morfológica, granulométrica e, também, o teor de umidade. Com os materiais caracterizados, foram desenvolvidas nove composições variando-se o teor de lodo de estação de tratamento de água entre 25 e 50%, o teor de lama de polimento de mármore entre 35 e 50% e o resíduo de produção de cal entre 10 e 30%. Os compósitos foram submetidos a ensaios de resistência mecânica, absorção de água, análise química, mineralógica e morfológica. Os materiais desenvolvidos apresentaram, no 3° dia de cura, valor de resistência mecânica máxima de 4,65 MPa, no 7° dia 6,36 MPa, no 14° dia 6,74 MPa, no 28° dia 5,98 MPa, no 60° dia 8,52 MPa, no 90° dia 11,75 MPa e no 180° dia 12,06 MPa. Os valores de absorção de água aos 28 dias de cura variaram de 16,27 a 26,32% e aos 90 dias, de 13,57 a 23,56%. / The rapid population growth is the great motivator for the development of the construction industry and the increased demand for drinking water, resulting in a gradual increase in the generation of solid waste. Thus, this work was carried out in order to recycle industrial and municipal wastes incorporating them into materials for civil construction. The composite produced from water treatment sludge and marble polishing mud, applying lime production waste as a binder, was evaluated for its mechanical performance and its morphological structure. The raw materials were characterized for their chemical composition, mineralogy, morphology, particle size and also the moisture content. With the featured materials nine compositions have been developed varying the content of the water treatment sludge between 25 to 50%, marble polishing mud between 35 to 50% and the lime production waste between 10 to 30%. The composites were subjected to mechanical strength tests, water absorption, chemical and mineralogical composition and morphology. The developed materials presented, on the 3rd day of hydration, maximum strength value of 4.65 MPa, the 7th day 6.36 MPa, on the 14th day 6.74 MPa, the 28th day 5.98 MPa, on the 60th day 8.52 MPa at 90th day 11.75 MPa and 180th day 12.06 MPa. The water absorption values after 28 days of hydration ranged from 16.27% to 26.32% and after 90 days, from 13.57% to 23.56%.
306

An evaluation of strategic management of landfill sites: A case study of Thohoyandou Block J. landfill site, Vhembe District Municipality, Limpopo Province

Nefale, Anza 18 May 2018 (has links)
MENVSC / Department of Ecology and Resource Management / The purpose of this study was to evaluate the strategic management of the Thohoyandou Block J landfill site. There are limited documented materials on strategic management of landfill sites in South Africa. As a result, this study sought to close this gap and expose new insights that it deemed to be of great importance in the management and operations of landfill sites. The capacity of a TBJ landfill site in terms of its efficiency in disposing waste, adherence to rules and procedures and the overall management of the site are the key areas of this study. The dominant types and sources of solid waste disposed at the TBJ landfill site, efficiency and effectiveness of operation of TBJ landfill site and operational challenges are the main areas covered in this study. The study adopted the mixed methods approach, involving both qualitative and quantitative research methods. Both primary and secondary data were acquired. Primary data were obtained through a questionnaire, an interview and field observation, using an observation checklist. Secondary data were obtained from ArcGIS Desktop Help 9.2 and documented materials from the Thulamela Local Municipality and the TBJ landfill site, the Integrated Waste Management Plan, Integrated Development Plan, TBJ landfill site’s monthly report, audit report and landfill site’s operating plan. Basically, field observation and a questionnaire completed by the waste manager, landfill operator and supervisor, were used to collect data on the operational challenges of TBJ landfill site and to obtain data on the efficiency and effectiveness at which the TBJ landfill site is operating. Waste pickers were interviewed and field observation was undertaken, to identify the dominant types and sources of waste disposed at the TBJ landfill site. A questionnaire completed by TBJ landfill operator, ArcGIS Desktop Help 9.2 for field measurement, reports of the amount of waste recorded and the municipality’s database, were utilized to elicit data regarding the determination of the capacity of TBJ landfill site. The results obtained revealed that the TBJ landfill site’s remaining capacity is 317 085 m3, which will be exhausted in the next 4 years. Plastics were found to be the dominant waste disposed at the TBJ landfill site, at 40%, followed by card-boxes, which constituted 32%. The dominant sources of solid waste generation in the TBJ landfill site were households, at 51%, followed by commercial, at 31% and industrial, at 11%. The absence of a weighbridge, to weigh loads of waste, frequent break down of equipment, lack of equipment required to operate the TBJ landfill site efficiently and the presence of fire hazards, were some of the / NRF
307

Stoffliche Nutzung industrieller Abprodukte in Biogasanlagen am Beispiel Apfeltrester

Bedrich, Karl 30 March 2011 (has links)
Die folgende Arbeit beschreibt Potentiale und Risiken der Nutzung industrieller Abprodukte am Beispiel des Apfeltrester – einem Pressrückstand der Apfelsaftgewinnung. Dieser spielt aus finanzieller und ökologischer Sicht als Abprodukt eine steigende Rolle bei der Biogassynthese. Dabei werden die Ergebnisse des vorangegangenen Fachpraktikums vorgestellt und diskutiert. Darauf aufbauend wurden Thesen erstellt und anhand ermittelter Messwerte sowie der Literatur verifiziert. Schlussendlich werden in einer Wirtschaftlichkeitsrechnung Kosten von Bezug, Lagerung und Beschickung den Gewinnen aus der Einspeisevergütung gegenüber gestellt. Es konnte gezeigt werden, dass Apfeltrester unter Laborbedingungen nicht die befürchtete Übersäuerung des anaeroben Abbauprozesses zur Folge hatte, sondern unter vergleichbaren Erträgen mit leicht höherer Sicherheit zur Maissilage bis zu einem gewissen Anteil zu Maissilage und Stallgülle zugesetzt werden kann.:Abstract 4 Zusammenfassung 4 Abkürzungsverzeichnis 5 1 Literaturrecherche 6 1.1 Grundlagen zur Biogassynthese 6 1.1.1. Übersicht des anaeroben Abbaus organischer Substanzen 6 1.1.1 Abgrenzung zum aeroben Abbau 6 1.1.2 Ausgangsprodukte 7 1.2 Phasen der Biogasbildung 11 1.2.1 Hydrolyse 11 1.2.2 Acidogenese 12 1.2.3 Acedogenese 12 1.2.4 Methanogenese 13 1.3 Einflussfaktoren des Biogasprozesses 14 1.3.1 Temperatur 14 1.3.2 pH-Wert und Gehalt an Fettsäuren 15 1.3.3 Nährstoffversorgung und Hemmstoffe 16 1.4 Verfahrenstechnische Betriebsparameter 18 1.4.1 Faulraumbelastung 18 1.4.2 Hydraulische Verweilzeit 18 2 Material und Methoden 20 2.1 Ausgangsmaterialien 20 2.1.1 Apfeltrester der Kelterei „Sachsenobst“ 20 2.1.2 Maissilage des „LLH Eichhof“ 24 2.1.3 Stallgülle des „LLH Eichhof“ 25 2.1.4 Fermentergülle des „LLH Eichhof“ 26 2.2 Diskontinuierlicher Gärtest (Batch-Versuch) 27 2.2.1 Apparativer Aufbau 27 2.2.2 Versuchsdurchführung 29 2.3 Kontinuierlicher Gärversuch 30 2.3.1 Apparativer Aufbau 30 2.3.2 Versuchsdurchführung 31 3 Ergebnisse 38 3.1 Biogasertragsermittlung 38 3.1.1 Variante „Null“ 39 3.1.2 Cellulose als Referenz 39 3.1.3 Apfeltrester 40 3.1.4 Maissilage 41 3.2 Kontinuierlicher Versuch 42 3.2.1 Erläuterung der dargestellten Diagramme 42 3.2.2 Variante „Null“ 45 3.2.3 Variante „Mais“ 48 3.2.4 Variante „Mix“ 53 3.2.5 Variante „Trester“ 57 4 Diskussion 62 4.1 Fehlerrechnung und -diskussion 62 4.1.1 Systematische Fehler der Laborversuche 62 4.1.2 Zufällige Fehler der Laborversuche 64 4.1.3 Fehlerrahmen und Vergleichbarkeit der Ergebnisse 65 4.2 Thesen 67 4.2.1 Die Vergärung von Apfeltrester als Co-Fermentat hat nur wenig Einfluss auf Ertrag und Stabilität des Gärprozesses unter Einsatzbedingungen 67 4.2.2 Die Zugabe von Apfeltrester verdünnt das Fermentat 72 4.2.3 Weder Lagerdauer noch Konservierung des Apfeltresters beeinflussen messbar den Methanertrag 75 5 Einsatz von Apfeltrester als Co-Fermentat in BGA 76 5.1 Politische und wirtschaftliche Rahmenbedingungen 76 5.2 Technische und wirtschaftliche Annahmen 81 5.3 Vorstellung der Vergleichsfälle 86 5.3.1 Optimierung hinsichtlich diskreter Parameter des Transports 86 5.3.2 Optimierung hinsichtlich der Verteilung des Tresters 87 5.3.3 Verwertung des Gärrestes 90 6 Fazit 93 Literaturverzeichnis 95 Abbildungsverzeichnis 100 Tabellenverzeichnis 103 Eidesstattliche Erklärung 105 Anhang 106 / Due to the increasing ecological and financial importance of industrial waste products in the recovery of biogas the following thesis describes potentials and risks of the usage of one of these products using apple pomace – the filter cake of the apple juice production. Thereby the issues of the three-month practical course in the LHL Eichhof, a laboratory in middle Germany, are shown and discussed. As conclusion several theses are given and verified with help of the taken measurements and scientific literature. At the end an economical calculation compares the present costs of purchase, storage and processing with the proceeds of the reimbursement by the german renewable energy sources act (EEG). Against the misgiving that apple pomace could decrease the pH-value to an unacceptable level for the anaerobic decomposition process the fermentation of this product gets a comparable output even with a little more reliability compared to corn silage when added up to a defined level to corn silage and slurry.:Abstract 4 Zusammenfassung 4 Abkürzungsverzeichnis 5 1 Literaturrecherche 6 1.1 Grundlagen zur Biogassynthese 6 1.1.1. Übersicht des anaeroben Abbaus organischer Substanzen 6 1.1.1 Abgrenzung zum aeroben Abbau 6 1.1.2 Ausgangsprodukte 7 1.2 Phasen der Biogasbildung 11 1.2.1 Hydrolyse 11 1.2.2 Acidogenese 12 1.2.3 Acedogenese 12 1.2.4 Methanogenese 13 1.3 Einflussfaktoren des Biogasprozesses 14 1.3.1 Temperatur 14 1.3.2 pH-Wert und Gehalt an Fettsäuren 15 1.3.3 Nährstoffversorgung und Hemmstoffe 16 1.4 Verfahrenstechnische Betriebsparameter 18 1.4.1 Faulraumbelastung 18 1.4.2 Hydraulische Verweilzeit 18 2 Material und Methoden 20 2.1 Ausgangsmaterialien 20 2.1.1 Apfeltrester der Kelterei „Sachsenobst“ 20 2.1.2 Maissilage des „LLH Eichhof“ 24 2.1.3 Stallgülle des „LLH Eichhof“ 25 2.1.4 Fermentergülle des „LLH Eichhof“ 26 2.2 Diskontinuierlicher Gärtest (Batch-Versuch) 27 2.2.1 Apparativer Aufbau 27 2.2.2 Versuchsdurchführung 29 2.3 Kontinuierlicher Gärversuch 30 2.3.1 Apparativer Aufbau 30 2.3.2 Versuchsdurchführung 31 3 Ergebnisse 38 3.1 Biogasertragsermittlung 38 3.1.1 Variante „Null“ 39 3.1.2 Cellulose als Referenz 39 3.1.3 Apfeltrester 40 3.1.4 Maissilage 41 3.2 Kontinuierlicher Versuch 42 3.2.1 Erläuterung der dargestellten Diagramme 42 3.2.2 Variante „Null“ 45 3.2.3 Variante „Mais“ 48 3.2.4 Variante „Mix“ 53 3.2.5 Variante „Trester“ 57 4 Diskussion 62 4.1 Fehlerrechnung und -diskussion 62 4.1.1 Systematische Fehler der Laborversuche 62 4.1.2 Zufällige Fehler der Laborversuche 64 4.1.3 Fehlerrahmen und Vergleichbarkeit der Ergebnisse 65 4.2 Thesen 67 4.2.1 Die Vergärung von Apfeltrester als Co-Fermentat hat nur wenig Einfluss auf Ertrag und Stabilität des Gärprozesses unter Einsatzbedingungen 67 4.2.2 Die Zugabe von Apfeltrester verdünnt das Fermentat 72 4.2.3 Weder Lagerdauer noch Konservierung des Apfeltresters beeinflussen messbar den Methanertrag 75 5 Einsatz von Apfeltrester als Co-Fermentat in BGA 76 5.1 Politische und wirtschaftliche Rahmenbedingungen 76 5.2 Technische und wirtschaftliche Annahmen 81 5.3 Vorstellung der Vergleichsfälle 86 5.3.1 Optimierung hinsichtlich diskreter Parameter des Transports 86 5.3.2 Optimierung hinsichtlich der Verteilung des Tresters 87 5.3.3 Verwertung des Gärrestes 90 6 Fazit 93 Literaturverzeichnis 95 Abbildungsverzeichnis 100 Tabellenverzeichnis 103 Eidesstattliche Erklärung 105 Anhang 106
308

Assessment of industrial waste load of River Borkena and its effect on Kombolcha town and the surrounding communities

Kebebew Kassaye Beyene 07 1900 (has links)
Water pollution is a major threat to human population and dumping of pollutants into water body result in rapid deterioration of water quality and affect the ecological balance in the long run. The present study was undertaken to assess pollution load from river Borkena. In urban and suburban parts of Kombolcha, the use of industrial wastewater for irrigation purpose is a common practice. Local farmers in Borkena watershed use the wastewater to irrigate their agricultural fields for cultivation of vegetables. But they suffered from loss of productivity of leafy vegetables and skin injury because of their exposure to the wastewater during irrigation practices. That is why this study focused on assessing the amount of industrial waste load on river Borkena and its effects on communities in the watershed. The main aim of this study was: to assess the physico-chemical characteristics of River Borkena before and after industrial waste discharges mixed to it by the waste carrier small streams; and its environmental impact on the surrounding communities and vegetable farms. The methodology consisted: 1) Basic survey in order to assess the physical and chemical characteristics of the river water, and 2) a case study performed by focus group discussions with the community authorities and farmers in the study area who used the river water mainly for irrigation purposes. Sampling was conducted at 6 sites in the study area during low and high flow periods with an interval of three months for a period of one year in order to account for the seasonal hydrological cycle of the river water. Laboratory measurements of river water and leafy vegetables for metal concentration were also determined to investigate the effect of the use of the river water for growing vegetables and other personal cases. The findings of this dissertation showed metal concentrations in leafy vegetables and irrigation water are within the permissible limits of FAO/WHO standards and not significant for the time being, but is expected to be a challenge in the near future if not well addressed. The concentrations of metals in leafy vegetables will provide baseline data and it shows that, in the current situation consumption of leafy vegetables grown in the study area may not have health risks in the context of metal concentrations. To avoid the entrance of metals into the food chain, municipal or industrial wastes should not be drained into the river and farmlands without prior treatment. The continuous monitoring of the soil, vegetable plant and irrigation water quality are prerequisites for the prevention of potential river water. Laboratory measurements of river water and leafy vegetables for metal concentration were also determined to investigate the effect of the use of the river water for growing vegetables and other personal cases. The findings of this dissertation showed metal concentrations in leafy vegetables and irrigation water are within the permissible limits of FAO/WHO standards and not significant for the time being, but is expected to be a challenge in the near future if not well addressed. The concentrations of metals in leafy vegetables will provide baseline data and it shows that, in the current situation consumption of leafy vegetables grown in the study area may not have health risks in the context of metal concentrations. To avoid the entrance of metals into the food chain, municipal or industrial wastes should not be drained into the river and farmlands without prior treatment. The continuous monitoring of the soil, vegetable plant and irrigation water quality are prerequisites for the prevention of potential health hazards to human beings. Finally this study fills the gaps in information for concerned regional and federal governmental offices and may use it as an input to design regulations and policies which benefits the communities in the watershed. / Environmental Sciences / Ph. D. (Environmental Science)
309

Satsvisa laboratorieförsök för utvärdering av kolkällor i denitrifikation / Lab-scale batch experiments for evaluation of carbon sources in denitrification

Tejde, Lisa January 2022 (has links)
I takt med att Uppsala växer behöver kapaciteten för avloppsvattenrening på Kungsängsverket byggas ut. För att möta en framtida ökad belastning bedömer Uppsala Vatten & Avfall AB att en kolkälla kommer behöva tillsättas i den biologiska kvävereningen för att effektivisera den heterotrofa denitrifikationen på Kungsängsverket, som idag sker utan tillsats av kolkälla. Potentialen till förbättrad denitrifikation med olika kolkällor utvärderades genom satsvisa laboratorieförsök och litteraturstudier. Syftet var att bättre förstå de studerade kolkällornas funktion och prestanda i denitrifikation för att ge underlag inför en framtida fullskalig implementering av kolkälla. Det övergripande målet var att identifiera vilken eller vilka kolkällor som är mest fördelaktiga med avseende på reningseffektivitet, processpåverkan, doseringsbehov, ekonomi och miljöpåverkan. Triplikata försök genomfördes som denitrifikationstester med aktivt slam vid en genomsnittlig slamtemperatur på 14 ℃ och pH 7-8, där fem externa kolkällor (etanol, Brenntaplus VP1 och tre industriella restprodukter) samt försedimenterat avloppsvatten testades. I litteraturstudien inkluderades även metanol. Från försöksdata bestämdes specifika denitrifikationshastigheter, COD/N-kvoter och utbyteskoefficienter. Även bieffekter såsom nitritackumulering och fosforsläpp studerades. Därefter uppskattades doseringsbehov och kostnader baserat på erhållna resultat och antaganden om framtida produktionsmål för nitratkväve. En likartad prestanda erhölls med en av restprodukterna (RTP-vätska) och etanol som uppnådde högst denitrifikationshastigheter och reduktionsgrader (98 % respektive 97 %). Doseringsbehovet uppskattades vara 4 gånger högre med RTP-vätska jämfört med etanol. Med de två andra restprodukterna (dextrandrank och sackaroslösning) uppnåddes lägst denitrifikationseffektivitet och reduktionsgraderna uppgick till 79 % respektive 47 %. Vid test av sackaroslösning observerades dessutom ofullständig denitrifikation samt höga fosforsläpp. Dextrandranken uppträdde på liknande sätt. I egenskap av restprodukt är RTP-vätskan intressant för fortsatt utvärdering. Fullskalig implementering av RTP-vätska förutsätter att doseringsbehoven kan tillgodoses samt att lämplig distribuering och lagerhållning kan ordnas på Kungsängsverket. / The city of Uppsala is expanding and consequently enhanced capacity at the wastewater treatment plant of Kungsängen will be required in the future. As for the biological nitrogen removal process, Uppsala Vatten & Avfall AB expects an additional carbon source to be necessary in the future denitrification process. Currently, the nitrogen removal is employed without the addition of a carbon source. The potential of enhancing denitrification with different carbon sources was evaluated by conducting lab-scale batch tests and compiling literature data. The objective of this work was to better understand the performance of the chosen carbon sources as electron donors in heterotrophic denitrification and thereby provide groundwork for a future full-scale implementation of a carbon source. Based on information drawn from batch tests and literature, the carbon sources were evaluated with respect to removal efficiency, process compliance, quantitative dosing requirements, costs, and environmental sustainability. Lab-scale trials were conducted as denitrification tests (triplicate) at a mean sludge temperature of 14 ℃ and pH 7-8 with five external carbon sources (ethanol, Brenntaplus VP1, and three industrial waste products) and pretreated wastewater. In the literature review, methanol was included as well. Results obtained from the batch tests were used to determine kinetic parameters, mainly specific denitrification rates, COD/N ratios, and anoxic yield coefficients. Moreover, unwanted side effects due to addition of carbon sources were examined. Dosing requirements and costs were assessed based on previously determined kinetic parameters and supposed future production guidelines for effluent quality with respect to nitrate concentration. Similar performance was observed with one of the waste products (RTP liquid) and ethanol which achieved the highest denitrification rates and degree of removal (98 and 97 %, respectively). The estimated dosing requirement was 4 times higher with the RTP liquid compared to ethanol. The other two waste products, solutions of fructose (dextran) and sucrose, reached the lowest denitrification efficiency and removal degrees were 79 and 47 %, respectively. During tests with sucrose solution, incomplete denitrification and release of phosphorous were observed. The fructose solution showed somewhat similar behavior but to a lesser degree. Being a waste product, the RTP liquid is interesting for future evaluation. Full-scale implementation needs further considerations regarding dosing requirements, distribution, and storage conditions at the site of Kungsängsverket.
310

Avaliação do potencial de aplicação dos preceitos da logística reversa de resíduos sólidos ao setor da construção civil em Curitiba, Paraná / Evaluation of the potential application of the precepts of solid waste reverse logistics to the civil construction sector in Curitiba, Paraná

Schamne, Annelise Nairne 13 December 2016 (has links)
Apesar da significativa representatividade do setor da construção civil na economia, o gerenciamento dos resíduos sólidos gerados pelo setor ainda é um desafio na maioria dos municípios brasileiros. Os resíduos da construção civil (RCC) são gerados nas atividades relacionadas à construção, comércio e indústria de materiais da construção civil. Estes resíduos quando não recebem tratamento e destinação adequados além de causarem impactos ambientais, afetam direta ou indiretamente a saúde, segurança e o bem estar da população, interferindo nas atividades sociais e econômicas e na qualidade dos recursos ambientais. Neste contexto, a logística reversa é vista como alternativa para gestão adequada dos resíduos, quando bem planejada e executada. A logística reversa está prevista na Lei no 12.305/2010, que trata sobre a Política Nacional dos Resíduos Sólidos (PNRS). No entanto, a implantação da logística reversa ainda é um desafio para alguns setores devido às dificuldades inerentes a este sistema e a falta de informações quanto à operacionalização e regulamentação. Tendo em vista esta dificuldade, este trabalho tem como objetivo avaliar o potencial de aplicação dos preceitos da logística reversa ao setor da construção civil na cidade de Curitiba e propor um modelo conceitual, destacando as responsabilidades dos principais participantes da cadeia produtiva da construção civil. Na primeira etapa da pesquisa, profissionais da construção civil foram selecionados para responder, com auxílio da técnica Delphi, um questionário, elaborado com base na revisão da literatura, a fim de selecionar critérios relevantes para compor o sistema de logística reversa no setor da construção civil. Na primeira rodada Delphi os profissionais opinaram sobre a relevância dos critérios escolhidos para compor o sistema de logística reversa e na segunda rodada foi realizada a análise multicritério com auxílio do Processo de Análise Hierárquica (AHP) a fim de ponderar e hierarquizar os critérios selecionados. Os resultados foram analisados na ferramenta BPMS AHP Excel e exportados por meio de gráficos. Nesta etapa da pesquisa foi demonstrado que a aplicação do questionário Delphi em conjunto com o AHP auxilia a tomada de decisão dos agentes da cadeia produtiva da construção civil. Os resultados apontam a importância da relação colaborativa entre clientes e fornecedores na devolução materiais e as possíveis barreiras que podem dificultar a operacionalização do sistema de logística reversa no setor da construção civil como a falta de apoio do governo, conscientização da população e baixo incentivo para reutilização de RCC. Na etapa da idealização e elaboração do modelo conceitual, com o auxílio da ferramenta Free Mind, foi possível destacar o potencial de aplicação dos preceitos da logística reversa entre os principais agentes da cadeia produtiva da construção civil em Curitiba. O modelo proposto auxilia na compreensão do fluxo de materiais no sistema de logística reversa e as responsabilidades de cada prestador de serviço, na execução das atividades relacionadas à construção civil, incluindo o gerenciamento dos RCC, além do cumprimento da PNRS e minimização dos impactos ambientais. / Despite the significant representativeness of the construction sector in the economy, the management of solid waste generated by the sector is still a challenge in most Brazilian municipalities. Construction and Demoliton Waste (CDW) is generated in activities related to the construction, trade and construction materials industry. The CDW when not properly treated and destined besides causing environmental impacts can affect directly or indirectly the health, safety and welfare of the population, interfering in social and economic activities and the quality of environmental resources. In this context, reverse logistics is seen as one of the alternatives for proper waste management, when well planned and executed. Reverse logistics is provided for in Law 12.305/2010, which deals with the National Policy on Solid Waste (NPSW). However, the implementation of reverse logistics is still a challenge for some sectors due to the difficulties inherent in this system and the lack of information regarding operationalization and regulation. In view of this difficulty, this paper aims to evaluate the potential of applying the reverse logistics precepts to the civil construction sector in the city of Curitiba and to propose a conceptual model, highlighting the responsibilities of the main participants in the civil construction production chain. In the first stage of the research, professionals of construction industry were selected to answer, with the help of the Delphi technique, a questionnaire elaborated based on the literature review, in order to select relevant criteria to compose a reverse logistics system to the civil construction sector. In the first round of Delphi, the participants decided on the relevance of the criteria chosen to compose the reverse logistics system and in the second round a multicriteria analysis was carried out with the aid of Analytic Hierarchy Process (AHP) in order to weight and hierarchize the criteria selected. The results were analyzed in the BPMS AHP Excel tool and exported through graphs. In this stage of the research it was demonstrated that the application of Delphi questionnaire in conjunction with the AHP helps the decision making of the agents of the civil construction productive chain. The results point out the importance of the collaborative relationship between customers and suppliers in the return of materials and possible barriers that may hinder the operation of the reverse logistics system in the construction sector, such as a lack of government support, population awareness and a low incentive to CDW reuse. In the stage of idealization and elaboration of the conceptual model, with Free Mind tool, it was possible to highlight the potential of applying the reverse logistics precepts among the main agents of the civil construction production chain in Curitiba. The proposed model assists in understanding the flow of materials in the reverse logistics system and the responsibilities of each service provider in the execution of activities related to civil construction, including the management of CDW, besides compliance with NPSW and minimization of environmental impacts.

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