Il mais rappresenta una delle colture più diffuse nel Nord Italia. Negli ultimi anni si è assistito ad un notevole incremento della superficie a mais legato soprattutto all'uso dell'insilato di mais come substrato per la produzione di biogas. Per questo motivo è necessario avere il maggior numero di informazioni possibili per migliorare le performance della coltura. In letteratura ci sono molti studi che valutano l’impatto dell’ambiente e del management sulle caratteristiche chimico nutrizionali e sul potenziale metanigeno del foraggio di mais ma non ci sono lavori che considerano entrambi i parametri. L’obiettivo della tesi è stato quello di investigare come il danno da grandine , la genetica e il momento di raccolta possano influenzare la composizione della pianta intera tradotta come potenziale metanigeno e valore nutrizionale del foraggio. / In the Po Valley the maize crop represent one of the most cultivated plant used for cattle feeding but in the last 10 years it is also used as biogas substrate. Considering the importance of this cultivation, there is the continuous need to obtain information about this plant with the aim to improve the crop performance. There are numerous studies investigating the impact of environmental aspects and management practices on chemical and nutritional composition, and methane production in the literature but very few that evaluate those parameters together. The general objective of this thesis is to investigate how hail damage, type of hybrid and the harvesting date affect the whole plant composition. To accomplish this, two specific objectives are posed: i) verify the effects of hail damage levels on yield, chemical and nutritional feature as well as on BMP of maize grown in the Po Valley; and ii) to evaluate the value of different hybrids for animal nutrition and methane production in anaerobic fermenters and as delaying harvesting after the usual stage of maturity affects these features. It was also aimed to verify if chemical composition and in vitro digestibility tests could allow to estimate methane yield potential in maize whole plant.

Orientador: Marcus César Avezum Alves de Castro / Resumo: No Brasil são geradas quantidades significativas de resíduos orgânicos provenientes das perdas no segmento de produção e processamento da cadeia de fornecimento de alimentos, ou desperdiçadas no varejo e no consumo final. Ainda, no país há carência de aplicações do processo de digestão anaeróbia no tratamento dos resíduos orgânicos alimentares, tornando pertinente seu estudo. Este trabalho analisou a influência de diferentes proporções de resíduos alimentares no processo de biometanização. Os substratos consistiram de resíduos orgânicos coletados em restaurante universitário, sendo divididos em dois grupos: Resíduos de Pré-Preparo dos alimentos (RPP) e Resíduos de Sobras das refeições (RS). Testes em batelada foram realizados para avaliar o Potencial Bioquímico de Metano (BMP) das diferentes proporções de resíduos, sob condições mesofílica e termofílica, tendo como fontes de inóculos dois lodos anaeróbios granulares provenientes de reatores UASB (Upflow Anaerobic Sludge Blanket). Para verificar a atividade dos lodos foram realizados testes de Atividade Metanogênica Específica (AME), tendo o acetato como fonte de carbono, com aplicação de diferentes relações Substrato/Inóculo (So/Xo) (0,5, 1,0 e 1,5). Os resultados dos testes de AME sob condições mesofílica e termofílica demonstraram bom desempenho dos inóculos com índices 0,1965 e 0,1559 g DQOCH4.g STV-1.d-1, respectivamente, sendo que a relação So/Xo=1,0 foi a mais indicada para aplicação na biodigestão anaeróbia dos resíduo... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: In Brazil, significant amounts of organic waste are generated from losses in the production and processing segment of the food supply chain, or wasted on retail and final consumption. Still, in the country there is a lack of applications of the anaerobic digestion process in the treatment of organic food residues, making its study pertinent. This work analyzed the influence of different proportions of food residues on the biomethanization process. The substrates consisted of organic residues collected in a university restaurant, being divided into two groups: Food Pre-Preparation Residues (RPP) and Residues of Leftovers from meals (RS). Batch tests were carried out to evaluate the Biochemical Potential of Methane (BMP) of the different proportions of residues, under mesophilic and thermophilic conditions, having as inoculum sources two granular anaerobic sludge from UASB (Upflow Anaerobic Sludge Blanket) reactors. In order to verify the activity of the sludges, tests of Specific Methanogenic Activity (AME) were carried out, with acetate as carbon source, applying different Substrate/Inoculum (So/Xo) ratios (0.5, 1.0 and 1.5). The results of the AME tests under mesophilic and thermophilic temperatures showed good performance of the inoculum with indexes 0.1965 and 0.1559 g DQOCH4.g STV-1.d-1, respectively, with the ratio So/Xo=1.0 was the most indicated for application in anaerobic biodigestion of food waste. BMP tests under different proportions of food residues demonstrated ... (Complete abstract click electronic access below) / Mestre

Submitted by Neusa Fagundes (neusa.fagundes@unioeste.br) on 2017-09-05T19:08:26Z No. of bitstreams: 1 Thiago_Edwiges2017.pdf: 2041114 bytes, checksum: f435c702dd49431aa0534c4ce49e2533 (MD5) / Made available in DSpace on 2017-09-05T19:08:26Z (GMT). No. of bitstreams: 1 Thiago_Edwiges2017.pdf: 2041114 bytes, checksum: f435c702dd49431aa0534c4ce49e2533 (MD5) Previous issue date: 2017-08-18 / The economical development and urbanization process have contributed to the increase in solid waste generation and problems related to final disposal. Thus, the National Solid Waste Policy reinforces treatment in order to improve efficiency in the management of solid waste as one of its priorities and stimulates to recover and use energy. Anaerobic digestion has been suggested as a promising approach to the treatment of organic fraction of solid waste, mainly because it represents an opportunity to reduce environmental pollution and minimizes impacts concerning the energy crisis. So, this trial aimed at evaluating FVW biogas potential, collected in a wholesale market (Unit from Foz do Iguaçu/PR) through batch and semicontinuous tests. Fruits and vegetables trading from that unit generates approximately 70,500 t year-1, with 2,800 kg d-1 solid waste, composed of almost 85% organic matter. The influence of chemical composition of twelve FVW different samples with different compositions on biochemical methane potential (BMP) was analyzed. The BMP ranged from 288 LN CH4 kg VS-1 to 516 LN CH4 kg VS-1, with significant statistical differences among means. This was explained by in the waste chemical composition over time. BMP variation was most strongly correlated for lipid content and high calorific values (HCV). Linear regression analyses were carried out to develop statistical models to predict as fast as possible methane potential of this kind of waste. The models were analyzed according to chemical compounds and HCV based on simple and multiple regression. The model with the best statistical metrics included lipid, protein, cellulose, lignin, and HCV, with a 92.5% R² and lignin content negatively correlated to BMP. Since HCV and lipids were strongly correlated, and because HCV can be determined more rapidly than chemical composition, HCV may be useful for predicting BMP. In addition to batch tests, the performance of anaerobic digestion was also investigated in a semicontinuous mode using a FVW mixture as a single substrate. The performance of a continuous stirred tank reactor (CSTR) was monitored along with the gradual increase of organic loading rates (OLR) from 0.5 gVS L–1 d–1 to 5.0gVSL–1d–1. BMP of FVW used as a feedstock to CSTR was 370 LN CH4 kg VS-1 with 81% biodegradability. During the whole trial pH was stable and there was an adequate level of buffering capacity in the system. Volumetric biogas production (LN biogas L–1 d–1) increased linearly (R² = 94.4%) according to OLR increase. On the other hand, the specific methane production (LN CH4 kg VS-1) has registered the best performance at an OLR of 3.0 g VS L–1 d–1 and 30 days of hydraulic retention time, with 285 LN CH4 kg VS-1 added, reaching 74% of BMP measured by batch tests. A clear accumulation of volatile fatty acids (VFA) was monitored with a decreased specific methane yield was detected with an OLR above 3.0 g VS L–1 d–1. / O crescimento econômico e o processo de urbanização vêm contribuindo para o aumento da geração de resíduos sólidos e problemas relacionados à disposição final. A Política Nacional de Resíduos Sólidos reforça o tratamento com o intuito de melhorar a eficiência quanto ao gerenciamento dos resíduos sólidos no país, como uma de suas prioridades e enfatiza o incentivo à recuperação e ao aproveitamento energético. A biodigestão anaeróbia tem sido apontada como uma abordagem promissora ao tratamento da fração orgânica dos resíduos sólidos, sobretudo por representar oportunidade de reduzir a poluição ambiental e minimizar os impactos da crise energética. Assim, o objetivo deste trabalho foi avaliar o potencial de produção de biogás de resíduos de frutas e hortaliças (RFH) coletados na Central de Abastecimento (CEASA – Unidade de Foz do Iguaçu/PR) a partir de testes em batelada e em regime semicontínuo. A comercialização de frutas e hortaliças da unidade é de aproximadamente 70.500 t ano-1, com geração de resíduos sólidos de 2.800 kg d-1, compostos por aproximadamente 85% de matéria orgânica. A influência da composição química de doze amostras de RFH com diferentes composições sobre o potencial bioquímico de metano (PBM) foi analisada. O PBM dos resíduos variou entre 288 LN CH4 kg SV-1 e 516 LN CH4 kg SV-1, com diferenças estatísticas significativas entre as médias, o que pôde ser explicado pela variação na composição química dos resíduos ao longo do tempo. A variação do PBM foi mais fortemente correlacionada à variação do teor de lipídeos e do poder calorífico superior (PCS). Foram realizadas análises de regressão linear visando desenvolver modelos estatísticos para estimar, de forma mais rápida, o potencial metanogênico deste tipo de resíduo. Os modelos foram analisados considerando os componentes químicos e o PCS a partir de regressão linear simples e múltipla. O modelo com as melhores métricas estatísticas foi obtido considerando lipídio, proteína, celulose, lignina e PCS, com R² de 92,5% e com teor de lignina negativamente correlacionado ao PBM. Como o PCS e os lipídeos apresentaram forte correlação, e como o PCS pode ser determinado, em geral, de forma mais rápida que a composição química, o PCS pode ser considerado um parâmetro útil para a estimava do PBM. Além dos testes em batelada, investigou-se também o desempenho da biodigestão anaeróbia em regime semicontínuo utilizando-se uma mistura de RFH como único substrato. O desempenho de reator de mistura completa (do inglês CSTR) foi monitorado juntamente com o aumento gradativo da carga orgânica volumétrica (COV) de 0,5 g SV L-1 d-1 até 5,0g SV L-1 d-1. O PBM dos RFH utilizado para alimentar o reator foi 370 LN CH4 kg SV-1 com biodegradabilidade de 81%. Durante todo o ensaio o pH se manteve estável e o sistema apresentou boa capacidade tampão. A produção volumétrica de biogás (LN biogás L-1 d-1) aumentou de forma linear (R² = 94,4%) de acordo com aumento da COV. Já a produção específica de metano (LN CH4 kg SV-1) indicou o melhor desempenho com COV de 3,0 g SV L-1 d-1 e 30 dias de tempo de retenção hidráulica, com 285 LN CH4 kg SV-1 adicionados, e atingiu 74% de PBM, medido a partir dos testes em batelada. Observou-se um acúmulo evidente de ácidos graxos voláteis (AGV), com consequente redução da produção de metano a partir da COV acima de 3,0 g SV L-1 d-1.

<p>Anaerobic digestion uses a mixed, microbial community to convert organic wastes to biogas, thereby generating a clean renewable energy and reducing greenhouse gas emissions. However, few studies have quantified the relationship between waste composition and the subsequent physical and chemical changes in the digester. This Ph.D. dissertation aimed to gain new knowledge about how these differences in waste composition ultimately affect digester function. This dissertation examined three areas of digester function: (1) hydrogen sulfide production, (2) digester foaming, and (3) methane yield. </p> <p>To accomplish these aims, a variety of materials from four different large-scale field digesters were collected at different time points and from different locations within the digester systems, including influent, liquid in the middle of the digesters, effluent, and effluent after solids separation. The materials were used for biochemical methane potential (BMP) tests in 43 lab-scale lab-digester groups, each containing triplicate or duplicate digesters. The materials from field digesters and the effluents from the lab-digesters were analyzed for an extensive set of chemical and physical characteristics. The three areas of digester function were examined with the physical and chemical characteristics of the digester materials and effluents, and the BMP performances. </p> <p>Hydrogen sulfide productions in the lab-digesters ranged from non-detectable to 1.29 mL g VS^-1. Higher H₂S concentrations in the biogas were observed within the first ten days of testing. The initial Fe(II) : S ratio and OP concentrations had important influences on H₂S productions. Important parameters of digester influents related to digester foaming were the ratios of Fe(II) : S, Fe(II) : TP, and TVFA : TALK; and the concentrations of Cu. Digesters receiving mixed waste streams could be more vulnerable to foaming. The characteristics of each waste type varied significantly based on substrate and inoculum type, and digester functioning. The influent chemical characteristics of the waste significantly impacted all aspects of digester function. Using multivariate statistics and machine learning, models were developed and the prediction of digester outcomes were simulated based on the initial characteristics of the waste types. </p>

In horse keeping horse manure is produced, which can be utilized as a fertilizer or considered a waste. Horse manure constitutes a resource in terms of both plant nutrients and energy. In addition energy policies and objectives aim at replacing fossil fuels with renewable energy sources. The interest to improve resource recovery of horse manure increases due various incentives for renewable vehicle fuels, legal requirements on management of manure, and environmental impact from current horse manure management. This thesis aims at describing horse manure management in a life cycle perspective. This is made by (1) identifying factors in horse keeping affect­ing the possibility to use horse manure as a biogas feedstock and to recycle plant nutrients, (2) analysing factors in anaerobic digestion with influence on methane potential and biofertilizer nutrient content and (3) comparing the environmental impact from different horse manure treatment methods. Literature reviews, systematic combining, and simulations have been used as research methods. The results show that horse keeping activities such as feeding, indoor keeping, outdoor keeping and manure storage affect the amount and charac­teristics of horse manure and thereby also the possibilities for anaerobic digestion horse manure. Transport affects the collected amount and spread­ing affects loss of nutrients and nutrient recycling. Simulation results in­dicate the highest methane yield and energy balance from paper bedding, while straw and peat gave a higher nutrient content of the biofertilizer. The highest methane yield was achieved with a low rate of bedding, which in the cases of woodchips and paper is also preferable for plant nutrient recycling. Still, results indicate the best energy balance from anaerobic digestion with a high ratio of bedding. The environmental impact assessment indicates a reduction in global warming potential for anaerobic digestion compared to incineration or composting. / Vid hästhållning alstras hästgödsel som kan användas som växtnäring eller anses vara ett avfall. Hästgödsel utgör både en växtnäringsresurs och en energi resurs. Dessutom styr uppsatta energimål mot att förnybar energi ska ersätta fossila bränslen. Intresset för att öka resursutnyttjandet av hästgödsel ökar på grund av olika incitament för förnybara drivmedel, lagstiftning om gödselhantering och miljöpåverkan från dagens hantering av hästgödsel. I den här avhandlingen beskrivs hästgödselhantering i ett livscykel­perspektiv genom att (1) identifiera olika faktorer vid hästhållningen som påverkar möjligheten att utvinna biogas ur hästgödsel och återföra näringen till jordbruksmark, (2) analysera faktorer i biogasprocessen som påverkar den specifika metanmängden och innehållet av växtnäring i gödseln och (3) jämföra olika gödselhanteringsmetoders miljöpåverkan. Metoderna i avhan­dlingen har varit litteraturstudier, systematisk kombination av teori och em­piri samt simulering. Resultaten visar att utfodringen, om och hur hästarna hålls inomhus och utomhus och hur hästgödsel lagras påverkar mängden hästgödsel och dess egenskaper, och därmed också hur den fungerar som ett biogassubstrat. Trans­porterna har betydelse för hur mycket gödsel som kan samlas in och spridas, medan gödselspridningen påverkar näringsförluster och närings återföring. Resultaten från simuleringarna indikerar högst metanutbyte och bäst energi­balans från papper som strömaterial, medan halm och torv gav högre växt­näringsinnehåll i biogödseln. De högsta resultaten på specifik metanmängd nåddes med låg andel strö, vilket också var positivt för växtnäringsinnehållet vid scenarierna med spån och papper. Samtidigt indikerar resultaten att en hög andel strömaterial ger den bästa energibalansen. Miljöpåverkansbedöm­ningen indikerar att potentialen för klimatpåverkan minskar om hästgödsel behandlas i en biogasprocess jämfört med förbränning eller kompostering.