A Diagnostic System for Improving Biomass Quality Based on a Sensor Network

Losses during storage of biomass are the main parameter that defines the profitability of using preserved biomass as feed for animal husbandry. In order to minimize storage losses, potential changes in specific physicochemical properties must be identified to subsequently act as indicators of silage decomposition and form the basis for preventive measures. This study presents a framework for a diagnostic system capable of detecting potential changes in specific physicochemical properties, i.e., temperature and the oxygen content, during the biomass storage process. The diagnostic system comprises a monitoring tool based on a wireless sensors network and a prediction tool based on a validated computation fluid dynamics model. It is shown that the system can provide the manager (end-user) with continuously updated information about specific biomass quality parameters. The system encompasses graphical visualization of the information to the end-user as a first step and, as a second step, the system identifies alerts depicting real differences between actual and predicted values of the monitored properties. The perspective is that this diagnostic system will provide managers with a solid basis for necessary preventive measures

Gas production, pressure and carbon dioxide absorption in maize silage

Orientador: Prof. Dr. Patrick SchmidtTese (doutorado) - Universidade Federal do Paraná, Setor de Ciências Agrárias, Programa de Pós-Graduação em Zootecnia. Defesa : Curitiba, 28/03/2022Inclui referênciasResumo: Uma diversidade de microrganismos está associada à ensilagem. Existe uma enorme diversidade de interações entre enzimas vegetais e atividades microbianas. Estudos recentes detectaram surpreendentemente uma nova fase de pressão negativa dentro dos silos e o aumento do teor de matéria seca após a fermentação da silagem. Essas observações justificam a realização deste estudo e afirmam a possibilidade de vias de fixação de CO2 ocorrerem em silagens. Este ensaio teve como objetivo avaliar a produção de gás, a pressão no interior dos silos e absorção de carbono ao suplementar os silos com CO2.Abstract: A diversity of microorganisms is associated with ensilage. There is a huge diversity interaction among plant enzymes and microbial activities. Recent studies have surprisingly detected a new phase of negative pressure inside the silos and the increase in dry matter content after silage fermentation. These observations justify the conduction of this study and affirm the possibility of CO2-fixing pathways in silages. This trial aimed to evaluate the gas production, the pressure inside the silos and the carbon absorption when supplementing the silos with CO2

Proceedings of the XVI international silage conference Hämeenlinna, Finland, 2-4 July 2012

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Heat and Mass Transfer in Baled Switchgrass for Storage and Bioconversion Applications

The temperature and moisture content of biomass feedstocks both play a critical role in minimizing storage and transportation costs, achieving effective bioconversion, and developing relevant postharvest quality models. Hence, this study characterizes the heat and mass transfer occurring within baled switchgrass through the development of a mathematical model describing the relevant thermal and physical properties of this specific substrate. This mathematical model accounts for the effect of internal heat generation and temperature-induced free convection within the material in order to improve prediction accuracy. Inclusion of these terms is considered novel in terms of similar biomass models. Two disparate length scales, characterizing both the overall bale structure (global domain) and the individual stems (local domain), are considered with different physical processes occurring on each scale. Material and fluid properties were based on the results of hydraulic conductivity experiments, moisture measurements and thermal analyses that were performed using the constant head method, TDR-based sensors and dual thermal probes, respectively. The unique contributions made by each of these components are also discussed in terms of their particular application within various storage and bioconversion operations. Model validation was performed with rectangular bales of switchgrass (102 x 46 x 36 cm3) stored in an environmental chamber with and without partial insulation to control directional heat transfer. Bale temperatures generally exhibited the same trend as ambient air; although initial periods of microbial growth and heat generation were observed. Moisture content uniformly declined during storage, thereby contributing to minimal heat generation in the latter phases of storage. The mathematical model agreed closely with experimental data for low moisture content levels in terms of describing the temperature and moisture distribution within the material. The inclusion of internal heat generation was found to be necessary for improving the prediction accuracy of the model; particularly in the initial stage of storage. However, the effects of natural convection exhibited minimal contribution to the heat transfer as conduction was observed as the predominate mechanism occurring throughout storage. The results of this study and the newly developed model are expected to enable the maintenance of baled biomass quality during storage and/or high-solids bioconversion

Proceedings of the European Conference on Agricultural Engineering AgEng2021

This proceedings book results from the AgEng2021 Agricultural Engineering Conference under auspices of the European Society of Agricultural Engineers, held in an online format based on the University of Évora, Portugal, from 4 to 8 July 2021. This book contains the full papers of a selection of abstracts that were the base for the oral presentations and posters presented at the conference. Presentations were distributed in eleven thematic areas: Artificial Intelligence, data processing and management; Automation, robotics and sensor technology; Circular Economy; Education and Rural development; Energy and bioenergy; Integrated and sustainable Farming systems; New application technologies and mechanisation; Post-harvest technologies; Smart farming / Precision agriculture; Soil, land and water engineering; Sustainable production in Farm buildings