3,496 research outputs found

    Air pollution and livestock production

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    The air in a livestock farming environment contains high concentrations of dust particles and gaseous pollutants. The total inhalable dust can enter the nose and mouth during normal breathing and the thoracic dust can reach into the lungs. However, it is the respirable dust particles that can penetrate further into the gas-exchange region, making it the most hazardous dust component. Prolonged exposure to high concentrations of dust particles can lead to respiratory health issues for both livestock and farming staff. Ammonia, an example of a gaseous pollutant, is derived from the decomposition of nitrous compounds. Increased exposure to ammonia may also have an effect on the health of humans and livestock. There are a number of technologies available to ensure exposure to these pollutants is minimised. Through proactive means, (the optimal design and management of livestock buildings) air quality can be improved to reduce the likelihood of risks associated with sub-optimal air quality. Once air problems have taken hold, other reduction methods need to be applied utilising a more reactive approach. A key requirement for the control of concentration and exposure of airborne pollutants to an acceptable level is to be able to conduct real-time measurements of these pollutants. This paper provides a review of airborne pollution including methods to both measure and control the concentration of pollutants in livestock buildings

    Potential of duckweed for swine wastewater nutrient removal and biomass valorisation through anaerobic co-digestion

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    Over the last decades, phytodepuration has been considered an efficient technology to treat wastewaters. The present study reports a bench scale depuration assay of swine wastewater using Lemna minor. The highest observed growth rate obtained in swine wastewater was 3.1 ± 0.3 gDW m−2 day−1 and the highest nitrogen and phosphorus uptake were 140 mg N m−2 day−1 and 3.47 mg P m−2 day−1, respectively. The chemical oxygen demand removal efficiency in the swine wastewater assay was 58.9 ± 2.0%. Furthermore, the biomass valorisation by anaerobic co-digestion with swine wastewater was assessed. Results showed a clear improvement in specific methane production rate (around 40%) when compared to mono-substrate anaerobic digestion. The highest methane specific production, 131.0 ± 0.8 mL CH4 g−1 chemical oxygen demand, was obtained with a mixture containing 100 g of duckweed per liter of pre-treated swine wastewater. The water-nutrients-energy nexus approach showed to be promising for swine waste management.info:eu-repo/semantics/publishedVersio

    Developing a batch isolation procedure and running it in an automated semi-continuous unit : AWL CFD25 case study

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    A key challenge during the transition from laboratory/small batch to continuous manufacturing is the development of a process strategy that can easily be adopted for a larger batch/continuous process. Industrial practice is to develop the isolation strategy for a new drug/process in batch using the design of experiment (DoE) approach to determine the best isolation conditions and then transfer the isolation parameters selected to a large batch equipment/continuous isolation process. This stage requires a series of extra investigations to evaluate the effect of different equipment geometry or even the adaptation of the parameters selected to a different isolation mechanism (e.g., from dead end to cross flow filtration) with a consequent increase of R&D cost and time along with an increase in material consumption. The CFD25 is an isolation device used in the first instance to develop an isolation strategy in batch (optimization mode) using a screening DoE approach and to then verify the transferability of the strategy to a semicontinuous process (production mode). A d-optimal screening DoE was used to determine the effect of varying the input slurry. Properties such as solid loading, particle size distribution, and crystallization solvent were investigated to determine their impact on the filtration and washing performance and the characteristics of the dry isolated product. A series of crystallization (ethanol, isopropanol, and 3-methylbutan-1-ol) and wash solvents (n-heptane, isopropyl acetate and n-dodcane) were used for the process. To mimic a real isolation process, paracetamol-related impurities, acetanilide and metacetamol, were dissolved in the mother liquor. The selected batch isolation strategy was used for the semicontinuous isolation run. Throughput and filtration parameters, such as cake resistance and flow rate, cake residual liquid content and composition, cake purity, particle-particle aggregation, and extent and strength of agglomerates, were measured to evaluate the consistency of the isolated product produced during a continuous experiment and compared with the isolated product properties obtained during the batch process development. Overall, the CFD25 is a versatile tool which allows both new chemical entity process development in batch and the production of the active pharmaceutical ingredient in semicontinuous mode using the same process parameters without changing equipment. The isolated product properties gained during the semicontinuous run are overall comparable between samples. The residual solvent content and composition differs between some samples due to filter plate blockage. In general, the mean properties obtained during semicontinuous running are comparable with the product properties simulated using the DoE

    Advanced micro and nano fabrications for engineering applications

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    This document is a compilation of my selected research publications in micro and nano fabrications. The papers are largely arranged in chronological order to show the development of research interests. The research works are grouped into three sections. Section one consists of 34 research papers on micro fabrication in various materials. The research was motivated by the development of a finger nail sized micro engine as explained in Papers 1 and 2. Section two of the document includes some research activities and achievements on nanocomposite materials embedded in metallic and ceramic matrices. Section 3 includes the papers to reflect the research in developing nanostructure fabrication processes. The research contained in this DSc submission shows a continuous exploration and development of novel micro/nano fabrication processes. Although the submission covers research activities spanning 15 years, from 2000 to 2015, many of the research results represent the top technology of the time. They have contributed to the ever progressing manufacturing capability of the world. The research has encompassed both theoretical and experimental studies, contributing to the understanding of the processes and materials involved

    Gestión de riesgos de exposición ocupacional a las nanopartículas en un proyecto en desarrollo: Estudio de caso

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    The production of nanotechnology based products is increasing, along with the conscience of the possible harmful effects of some nanomaterials. Along with technological advances, there is the need to improve knowledge of safety and health and apply that knowledge to the workplace. The “safety-by-design” approaches are attracting attention as helpful tools to develop safer products and production processes. The Systematic Design Analysis Approach could help to identify the solutions to control workplace risks by defining the emission and exposure scenarios and the possible barriers to interrupt them. When managing risks during a photocatalytic ceramic tiles development project, it was possible to identify relevant nanoparticles emission scenarios and related barriers. Possible ways to reduce them could then be defined, which would in turn, lead to an inherently safer production process.La producción de productos basados en la nanotecnología va en aumento, junto con la conciencia de los posibles efectos nocivos de algunos nanomateriales. Junto con los avances tecnológicos, existe la necesidad de mejorar el conocimiento de la seguridad y salud y aplicar ese conocimiento en los entornos laborales. La enfoques "Safety-by-design” están atrayendo la atención como herramientas útiles para desarrollar productos y procesos de producción más seguros. El enfoque de Análisis Sistemática de Diseño podría ayudar a identificar las soluciones para el control de los riesgos laborales mediante la definición de los escenarios de emisiones y de exposición y los posibles obstáculos a interrumpirlos. Cuando la gestión de riesgos durante un proyecto de desarrollo de las azulejos cerámicos fotocatalíticos, fue posible identificar escenarios de emisiones de las nanopartículas relevantes y las barreras relacionadas. Así, las posibles formas de reducirlos podrían ser definidas, lo que, a su vez, pueden dar lugar a un proceso de producción inherentemente más seguro.The research was part of the SELFCLEAN – Selfcleaning ceramic surfaces Project, funded by QREN – Technological R&D Incentives System – Co-operation projects, Project No. 21533. The authors would like to thank their project partners for their co-operation
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