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- ItemRastreamento e prevalência de salmonella sp. na cadeia produtiva da pimenta-do-reino (piper nigrum) no Espírito Santo(Universidade Federal do Espírito Santo, 2024-09-20) Vinha, Mariana Barboza; Nascimento, Maristela da Silva do; https://orcid.org/0000-0003-1791-0361; Cassini, Sérvio Túlio Alves; https://orcid.org/0000-0001-5200-3666; https://orcid.org/0009-0002-3314-7896; Keller, Regina de Pinho; Silveira, Daniele Damasceno; Oliveira, Jairo Pinto de; Ventura, José AiresContamination of black pepper with Salmonella is a frequent problem in retail and imported shipments. However, there is scarce information about the prevalence of the pathogen in the initial stages of black pepper production chain. This study sought to bridge this gap in research by determining the prevalence, as well as quantifying, and identifying the main Salmonella serovars present during black pepper primary production and processing. Black pepper (233) and environmental (175) samples were collected from farms (354) and processing plants (54) in Espírito Santo, Brazil. The pathogen was detected in soil (16.7%), drying waste (20.4%), fallen berries (3.7%), threshed berries (14.3%), and dried peppercorns (22.2%) collected from farms. Salmonella was also detected in samples of raw material (11.1%), export products (16.7%), and processing waste (16.7%) collected from processing plants. A total of 12 serotypes were identified, and Salmonella Javiana showed the highest prevalence (38.8%). According to the results, contaminations can occur during black pepper harvest and post-harvest, increase or persist throughout post-harvest and remain in the grains produced on rural properties. The processing performed by exporting companies did not eliminate or reduce these contaminations to a safe level, resulting in contamination of the product intended for export The presence of the pathogen in the environment increases the risk of contamination of the fruits and pepper grains during processing. However, this risk can be reduced by improving hygiene practices during processing and by adopting Good Agricultural Practices (GAP) and Good Manufacturing Practices (GMP). To ensure product safety, it is essential to prevent contaminations and to make changes to the current production process, including the implementation of treatments that reduce and control contamination. Public policies aimed at improving rural sanitation, promoting the adoption of GAP, and advancing processing technologies are crucial for driving the necessary changes that will ensure the safety of black pepper produced in Espírito Santo.
- ItemEfeitos da remoção de nitrogênio amoniacal do inóculo e digestato líquido na produção de energia e estabilidade da digestão anaeróbia de resíduos alimentares(Universidade Federal do Espírito Santo, 2024-09-02) Assis, Tatiana Izato; Gonçalves, Ricardo Franci ; https://orcid.org/; http://lattes.cnpq.br/; https://orcid.org/0000-0001-7875-1750; http://lattes.cnpq.br/; Keller, Regina Pinho ; https://orcid.org/; http://lattes.cnpq.br/; Nariyoshi, Yuri Nascimento ; https://orcid.org/; http://lattes.cnpq.br/; Queiroz, Luciano Matos ; https://orcid.org/; http://lattes.cnpq.br/; Borges, Raquel Machado ; http://lattes.cnpq.br/This thesis investigates the valorization of food waste through anaerobic digestion, focusing on process optimization for biomethane production. The collected food waste exhibited a low C/N ratio (10.1 to 14.9). Therefore, a strategy for excess N removal was adopted. Initially, the study focused on ammonia removal from the inoculum (digestate) through volatilization and chemical precipitation of struvite, aiming to balance the nutrients by improving the C/N ratio and consequently biogas production. The treatment that used pH 8.7 and a molar ratio of Mg:PO₄ ³⁻ of 1:1 achieved the highest biomethane production (466.5 mL CH₄/gSV), representing a 74% increase compared to the control, with 94% biodegradability. Ammonia removal increased the process C/N ratio by up to 27.3%, enhancing energy recovery. Finally, a new operational strategy for reactors was evaluated, involving the recirculation of liquid digestate after nitrogen removal by volatilization and struvite precipitation. The condition with pH 9.5 and a molar ratio of Mg:PO₄ ³⁻ of 1:1 resulted in the removal of 45.5% of total ammoniacal nitrogen and 65.5% of free ammoniacal nitrogen, with improvements in alkalinity and organic matter removal (COD, VS, and TS) by 97%, 95%, and 91%, respectively. This strategy allowed for a reduction in the hydraulic retention time of the reactor, accelerating the stabilization of organic matter. The energy balance for the reactor with an HRT of 30 days was positive at 7.0 kWh/t of food waste. In summary, this thesis demonstrates that anaerobic digestion of food waste can be optimized through ammonia removal and liquid digestate recirculation, promoting a more sustainable and efficient management of this waste
- ItemParticles emission and transport due to wind erosion on beds and stockpiles : local and non-local aspects of turbulent fluid flow dynamics(Universidade Federal do Espírito Santo, 2024-05-03) Morais, Cristina Lima de; Furieri, Bruno ; https://orcid.org/0000-0002-9736-0250; http://lattes.cnpq.br/6585455298349085; Caliman, Maria Clara Schuwartz Ferreira ; https://orcid.org/0000-0001-9323-5041; http://lattes.cnpq.br/9245815665956760; Harion, Jean-Luc ; https://orcid.org/0000-0003-4317-9146; http://lattes.cnpq.br/; Co-orientador4; ID do co-orientador4; Lattes do co-orientador4; Santos, Jane Meri ; https://orcid.org/0000-0003-3933-2849; http://lattes.cnpq.br/0120226021957540; Orientador2; https://orcid.org/; http://lattes.cnpq.br/; https://orcid.org/0000-0003-4557-9952; http://lattes.cnpq.br/3583322289076958; Albuquerque, Taciana Toledo de Almeida ; https://orcid.org/0000-0002-6611-0283; http://lattes.cnpq.br/1339985577872129; Reis Junior, Neyval Costa ; https://orcid.org/0000-0002-6159-4063; http://lattes.cnpq.br/4944106074149720; Nieckele, Angela Ourivio ; https://orcid.org/0000-0003-4836-8931; http://lattes.cnpq.br/6935503527357767; Sartim, Rafael ; https://orcid.org/0000-0002-5678-2027; http://lattes.cnpq.br/0380809249444032; 5º membro da banca; https://orcid.org/; http://lattes.cnpq.br/; 6º membro da banca; https://orcid.org/; http://lattes.cnpq.br/; 7º membro da banca; https://orcid.org/; http://lattes.cnpq.br/This study aims to provide a comprehensive understanding of particle behavior in both local and non-local contexts. We analyze the influence of different configurations of successive stockpiles on the re-emission potential of particles from their surroundings using the USEPA model. This analysis is important for industries that store granular materials in open yards, as it helps to understand the impact of stockpile arrangements on particle emission. However, the USEPA model relies on an empirical equation and has gaps in its consideration of non-erodible particles and their effects on turbulent structures. Additionally, the friction velocity distribution used in the model is derived from previous RANS numerical simulations, which may not be the most accurate. Moving from a non-local to a local perspective, we assess the influence of non erodible particles on the development of fluid flow structures at the particle level. We examine the role of turbulent structures in particle entrainment through LES simulations, which provide detailed information about the flow field. These simulations allowed us to generate probability density distributions of friction velocity for smooth and rough beds, which can be used to improve or develop more accurate environmental stochastic prediction models. Finally, we evaluate the similarity requirements of wind flow, particle entrainment, and particle transport in wind tunnel experiments to ensure they accurately represent real-scale scenarios. By addressing these similarity requirements, we discuss the conditions under which wind tunnel experiments can reliably simulate real conditions, which is essential for the future applicability of our findings
- ItemRecuperação de recursos de biomassa algácea cultivada com esgoto sanitário através de pré-tratamento hidrolítico para produção de biogás e carbonização da biomassa residual(Universidade Federal do Espírito Santo, 2024-04-17) Estevam, Renata; Gonçalves, Ricardo Franci; https://orcid.org/0000-0002-2048-9451; http://lattes.cnpq.br/9604327349698525; https://orcid.org/0000-0003-1562-5962; http://lattes.cnpq.br/9232793099134014; Coelho, Edumar Ramos Cabral; https://orcid.org/0000-0002-9220-5737; http://lattes.cnpq.br/2276795519317927; Keller, Regina de Pinho; https://orcid.org/0000-0002-9163-0715; http://lattes.cnpq.br/1765455668560897; Calijuri, Maria Lúcia; https://orcid.org/0000-0002-0918-2475; http://lattes.cnpq.br/4128051734077960; Soares, Renan Barroso; https://orcid.org/0000-0002-9508-0036; http://lattes.cnpq.br/2642899302303469This research aimed to address gaps in the sustainable valorization of algal biomass from wastewater, providing insights and innovative strategies to boost its reuse and promote sustainable development. The core objectives encompassed optimizing the reuse of algal biomass harvested from high-rate ponds, considering the presence and absence of coagulants, both organic and inorganic. The research assessed the influence of these coagulants and thermal and thermochemical pre-treatments at various stages, from biomass harvesting to the production of biogas, activated carbons, and tests for toxic dye adsorption—a critical issue for efficient wastewater disinfection. An innovative approach was adopted for algal biomass harvesting, involving an experimental pilot that enabled total solids content exceeding 2%, without the need for energy-intensive equipment. Pre-treatments were conducted under different experimental conditions, and operational parameters were obtained through a second-degree polynomial, a response surface methodology (RSM) providing high reliability to the results. Data collection involved laboratory physicochemical analyses, elemental analysis (CHNS-O), Fouriertransform infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA and DrTGA), scanning electron microscopy (SEM), and X-ray diffraction (XRD). Statistical methods were applied to interpret the results, ensuring the reliability of conclusions and scalability. Results indicated that specific pre-treatments, such as 78°C for 7 hours in pure biomass, 80°C for 1.5 hours at pH 1 in Tanfloc-treated biomass, and 90°C for 3 hours at pH 11 in biomass treated with aluminum sulfate, provided efficiency in soluble COD solubilization, solid reduction, and nutrient solubilization, demonstrating the feasibility of optimized reuse from hydrolysis residues. Pre-treated biomass used in anaerobic digestion, especially algal biomass pre-treated at 90°C for 3 hours at pH 11, showed remarkable results, indicating no microbial inhibition by aluminum salts and viability for implementation in integrated systems targeting biogas production. In the context of reuse pathways, pre-treated biomass used as a precursor material in activated carbon production achieved significantly higher specific surface areas compared to untreated algal biomass. Changes in FTIR spectra indicated beneficial modifications in the composition of activated carbons produced from pretreated biomass, particularly an increase in the thermostability of activated carbons derived from pre-treated biomass, reflecting a decrease in recalcitrant compounds in the biomass. These results provided valuable insights for optimizing activated carbons in adsorption processes. Physical and chemical characteristics resulting from synergistic effects among pre-treatments, carbonization, and activation significantly contributed to conducting toxic dye adsorption tests, revealing the potential of these activated carbons as effective adsorbents for removing persistent toxic dyes in wastewater at low concentrations, indicating their viability for future modeling and applications of activated carbons in the integrated context of microalgae biorefineries. The research goes beyond a mere understanding of processes, significantly contributing to science. Key highlights include identifying new routes for waste reuse, optimizing biogas production, understanding the effects of pre-treatments on activated carbons and coagulants, both organic and inorganic and applying these materials to remove toxic dyes.
- ItemEvaluation of nanotechnological processes applied to the harvesting of microalgae biomass(Universidade Federal do Espírito Santo, 2023-07-23) Barizao, Ana Carolina de Lima; Cassini, Servio Tulio Alves; https://orcid.org/0000000152003666; http://lattes.cnpq.br/2519874649699294; https://orcid.org/0000-0003-2381-2020; http://lattes.cnpq.br/1087798223713901; Keller, Regina de Pinho; https://orcid.org/0000000291630715; http://lattes.cnpq.br/1765455668560897; Antunes, Paulo Wagnner Pereira; https://orcid.org/; http://lattes.cnpq.br/5259147170249880; Oliveira, Jairo Pinto de; https://orcid.org/0000000175951183; http://lattes.cnpq.br/2228283301316218; Silva, Andre Romero da; https://orcid.org/0000000214976093; http://lattes.cnpq.br/3079774974302460; Pinotti, Laura Marina; https://orcid.org/0000000250126811; http://lattes.cnpq.br/5616576281329159As microalgas têm despertado interesse significativo devido às diversas aplicações na produção de biocombustíveis, alimentos funcionais, cosméticos e produtos farmacêuticos. Porém, um dos desafios encontrados durante sua produção é a etapa de colheita, que muitas vezes é trabalhosa e ineficiente. Neste contexto, a colheita utilizando nanopartículas magnéticas surge como uma técnica promissora para superar estas dificuldades. As nanopartículas podem aderir às paredes celulares das microalgas, permitindo a sua recuperação através da aplicação de um campo magnético. Algumas partículas podem ainda ser utilizadas para funcionalizar essas nanopartículas, melhorando suas características e otimizando sua aplicação. Assim, este estudo forneceu uma visão abrangente das diversas aplicações potenciais das microalgas, enfatizando seu potencial no tratamento de águas residuais, fixação de CO2 e produção de bioprodutos, buscando resolver a etapa limitante por meio de abordagens inovadoras que incluem a seleção e análise de nanopartículas derivadas de diferentes fontes e seu uso otimizado na colheita de Chlorella sp. De acordo com os resultados da caracterização, as nanopartículas de duas fontes utilizadas foram a magnetita. Os experimentos foram otimizados por planejamento fatorial, onde as nanopartículas magnéticas (MNPs) sintetizadas em laboratório (funcionalizadas pelo tanino de Rhizophora mangle) e aplicadas na colheita de Chlorella sp, alcançaram uma eficiência de colheita (HE%) de 92,6% ((MNP-TNs concentração =1.000 mg L -1 ; qexp= 1,39 g pH=4), mantendo esta eficiência durante 5 ciclos de reaproveitamento. manter um HE%= 63% (qexp= 0,96 g. mg-1 ) De forma satisfatória, quando foram utilizadas nanopartículas obtidas de fonte alternativa (material particulado) tanto as MNPs (nuas) quanto as MNP-TAN (funcionalizadas com tanino comercial) apresentaram ótimo rendimento eficiência, sendo que as MNPs (nuas) obtiveram maior eficiência de colheita (HE%=86%; concentração de MNPs=1.250 mg. L-1 ; pH=3) do que as nanopartículas funcionalizadas (HE%=77%; concentração de MNP-TANs=1.100 mg . L -1 ; pH=3,5). Porém, para isso foi necessária uma maior concentração de MNPs em um pH mais baixo. A funcionalização contribuiu para a estabilização das partículas aumentando seus ciclos de reutilização de 3 (MNSs) para 7 ciclos (MNP-TANs). Embora neste caso as eficiências de colheita tenham sido um pouco inferiores, é interessante verificar que um material obtido de forma natural, com baixo custo e aplicado pela primeira vez para este fim também pode ser considerado altamente promissor para este fim.