926 resultados para Waste Isolation Pilot Plant (N.M.)


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Operators can become confused while diagnosing faults in process plant while in operation. This may prevent remedial actions being taken before hazardous consequences can occur. The work in this thesis proposes a method to aid plant operators in systematically finding the causes of any fault in the process plant. A computer aided fault diagnosis package has been developed for use on the widely available IBM PC compatible microcomputer. The program displays a coloured diagram of a fault tree on the VDU of the microcomputer, so that the operator can see the link between the fault and its causes. The consequences of the fault and the causes of the fault are also shown to provide a warning of what may happen if the fault is not remedied. The cause and effect data needed by the package are obtained from a hazard and operability (HAZOP) study on the process plant. The result of the HAZOP study is recorded as cause and symptom equations which are translated into a data structure and stored in the computer as a file for the package to access. Probability values are assigned to the events that constitute the basic causes of any deviation. From these probability values, the a priori probabilities of occurrence of other events are evaluated. A top-down recursive algorithm, called TDRA, for evaluating the probability of every event in a fault tree has been developed. From the a priori probabilities, the conditional probabilities of the causes of the fault are then evaluated using Bayes' conditional probability theorem. The posteriori probability values could then be used by the operators to check in an orderly manner the cause of the fault. The package has been tested using the results of a HAZOP study on a pilot distillation plant. The results from the test show how easy it is to trace the chain of events that leads to the primary cause of a fault. This method could be applied in a real process environment.

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This thesis is concerned with the use of the synoptic approach within decision making concerning nuclear waste management. The synoptic approach to decision making refers to an approach to rational decision making that assumes as an ideal, comprehensiveness of information and analysis. Two case studies are examined in which a high degree of synoptic analysis has been used within the decision making process. The case studies examined are the Windscale Inquiry into the decision to build the THORP reprocessing plant and the Nirex safety assessment of nuclear waste disposal. The case studies are used to test Lindblom's hypothesis that a synoptic approach to decision making is not achievable. In the first case study Lindblom's hypothesis is tested through the evaluation of the decision to build the THORP plant, taken following the Windscale Inquiry. It is concluded that the incongruity of this decision supports Lindblom's hypothesis. However, it has been argued that the Inquiry should be seen as a legitimisation exercise for a decision that was effectively predetermined, rather than a rigorous synoptic analysis. Therefore, the Windscale Inquiry does not provide a robust test of the synoptic method. It was concluded that a methodology was required, that allowed robust conclusions to be drawn, despite the ambiguity of the role of the synoptic method in decision making. Thus, the methodology adopted for the second case study was modified. In this case study the synoptic method was evaluated directly. This was achieved through the analysis of the cogency of the Nirex safety assessment. It was concluded that the failure of Nirex to provide a cogent synoptic analysis supported Lindblom's criticism of the synoptic method. Moreover, it was found that the synoptic method failed in the way that Lindblom predicted that it would.

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This study presents design and construction of a tri-generation system (thermal efficiency, 63%), powered by neat nonedible plant oils (jatropha, pongamia and jojoba oil or standard diesel fuel), besides studies on plant performance and economics. Proposed plant consumes fuel (3 l/h) and produce ice (40 kg/h) by means of an adsorption refrigerator powered from the engine waste jacket water heat. Potential savings in green house gas (GHG) emissions of trigeneration system in comparison to cogeneration (or single generation) has also been discussed.

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In this paper a Hierarchical Analytical Network Process (HANP) model is demonstrated for evaluating alternative technologies for generating electricity from MSW in India. The technological alternatives and evaluation criteria for the HANP study are characterised by reviewing the literature and consulting experts in the field of waste management. Technologies reviewed in the context of India include landfill, anaerobic digestion, incineration, pelletisation and gasification. To investigate the sensitivity of the result, we examine variations in expert opinions and carry out an Analytical Hierarchy Process (AHP) analysis for comparison. We find that anaerobic digestion is the preferred technology for generating electricity from MSW in India. Gasification is indicated as the preferred technology in an AHP model due to the exclusion of criteria dependencies and in an HANP analysis when placing a high priority on net output and retention time. We conclude that HANP successfully provides a structured framework for recommending which technologies to pursue in India, and the adoption of such tools is critical at a time when key investments in infrastructure are being made. Therefore the presented methodology is thought to have a wider potential for investors, policy makers, researchers and plant developers in India and elsewhere. © 2013 Elsevier Ltd. All rights reserved.

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The uptake in Europe of Energy from Waste (EfW) incinerator plants has increased rapidly in recent years. In the UK, 25 municipal waste incinerators with energy recovery are now in operation; however, their waste supply chains and business practices vary significantly. With over a hundred more plant developments being considered it is important to establish best business practices for ensuring efficient environmental and operational performance. By reviewing the 25 plants we identify four suitable case study plants to compare technologies (moving grate, fluidised bed and rotary kiln), plant economics and operations. Using data collected from annual reports and through interviews and site visits we provide recommendations for improving the supply chain for waste incinerators and highlight the current issues and challenges faced by the industry. We find that plants using moving grate have a high availability of 87-92%. However, compared to the fluidised bed and rotary kiln, quantities of bottom ash and emissions of hydrogen chloride and carbon monoxide are high. The uptake of integrated recycling practices, combined heat and power, and post incineration non-ferrous metal collections needs to be increased among EfW incinerators in the UK. We conclude that one of the major difficulties encountered by waste facilities is the appropriate selection of technology, capacity, site, waste suppliers and heat consumers. This study will be of particular value to EfW plant developers, government authorities and researchers working within the sector of waste management. © 2013 Elsevier Ltd.

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This paper presents a goal programming model to optimise the deployment of pyrolysis plants in Punjab, India. Punjab has an abundance of waste straw and pyrolysis can convert this waste into alternative bio-fuels, which will facilitate the provision of valuable energy services and reduce open field burning. A goal programming model is outlined and demonstrated in two case study applications: small scale operations in villages and large scale deployment across Punjab's districts. To design the supply chain, optimal decisions for location, size and number of plants, downstream energy applications and feedstocks processed are simultaneously made based on stakeholder requirements for capital cost, payback period and production cost of bio-oil and electricity. The model comprises quantitative data obtained from primary research and qualitative data gathered from farmers and potential investors. The Punjab district of Fatehgarh Sahib is found to be the ideal location to initially utilise pyrolysis technology. We conclude that goal programming is an improved method over more conventional methods used in the literature for project planning in the field of bio-energy. The model and findings developed from this study will be particularly valuable to investors, plant developers and municipalities interested in waste to energy in India and elsewhere. © 2014 Elsevier Ltd. All rights reserved.

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The uptake in Europe of Energy from Waste (EfW) incinerator plants has increased rapidly in recent years. In the UK, 25 municipal waste incinerators with energy recovery are now in operation; however, their waste supply chains and business practices vary significantly. With over a hundred more plant developments being considered it is important to establish best business practices for ensuring efficient environmental and operational performance. By reviewing the 25 plants we identify four suitable case study plants to compare technologies (moving grate, fluidised bed and rotary kiln), plant economics and operations. Using data collected from annual reports and through interviews and site visits we provide recommendations for improving the supply chain for waste incinerators and highlight the current issues and challenges faced by the industry. We find that plants using moving grate have a high availability of 87-92%. However, compared to the fluidised bed and rotary kiln, quantities of bottom ash and emissions of hydrogen chloride and carbon monoxide are high. The uptake of integrated recycling practices, combined heat and power, and post incineration non-ferrous metal collections needs to be increased among EfW incinerators in the UK. We conclude that one of the major difficulties encountered by waste facilities is the appropriate selection of technology, capacity, site, waste suppliers and heat consumers. This study will be of particular value to EfW plant developers, government authorities and researchers working within the sector of waste management. © 2013 Elsevier Ltd.

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Background and Objective: Medication non-compliance is a considerable obstacle in achievinga therapeutic goal, whichcan result in poorerhealthcare outcomes, increased expenditure, wastage and potential for medication resistance. The UK Government’s Audit Commission’s publication ‘A Spoonful of Sugar’1 addresses these issues and promotes self-medication systems as a possible solution. The self-medication system within the Liver Transplant Unit (LTU) was implemented to induct patients onto new post- transplantation medication regimes ready for discharge. The system involves initial consultations with both the Liver Transplant Pharmacist and Trans- plant Co-ordinator, supported with additional advice as and when necessary. Design: Following ethical approval, evaluation of the self-medication sys- tem for liver transplant patients was conducted between January and March 2004 via two methods: audit and structured post-transplantation interview. The audit enabled any discrepancies between current Hospital guidelines and Liver Transplant Unit (LTU) practices to be highlighted. Patient interviews generated a retrospective insight into patient acceptance of the self-medication system. Setting: LTU, Queen Elizabeth Hospital, Birmingham, England. Main Outcome Measures: LTU compliance with Hospital self-medication guidelines and patient insight into self-medication system. Results: A total of seven patients were audited. Findings illustrated that self- medication by transplant patients is a complex process which was not fully addressed by current Hospital self-medication guidelines. Twenty-three patients were interviewed, showing an overwhelming positive attitude to- wards participating in their own care and a high level of understanding towards their individual medication regimes. Following a drugs counselling session, 100% of patients understood why they were taking their medica- tion, and their doses, 95% understood how to take their medication and 85% were aware of potential side effects. Conclusions: From this pilot evaluation it can be stated that the LTU self-medication system is appreciated by patients and assists them in fully understanding their medication regimes. There appear to be no major defects in the system. However areas such as communication barriers and on-going internet education were illustrated as areas for possible future investigation. References: 1. Audit Commission. A spoonful of sugar – medicines management in NHS hospitals. London: Audit Commission; 2001.

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Hazardous radioactive liquid waste is the legacy of more than 50 years of plutonium production associated with the United States' nuclear weapons program. It is estimated that more than 245,000 tons of nitrate wastes are stored at facilities such as the single-shell tanks (SST) at the Hanford Site in the state of Washington, and the Melton Valley storage tanks at Oak Ridge National Laboratory (ORNL) in Tennessee. In order to develop an innovative, new technology for the destruction and immobilization of nitrate-based radioactive liquid waste, the United State Department of Energy (DOE) initiated the research project which resulted in the technology known as the Nitrate to Ammonia and Ceramic (NAC) process. However, inasmuch as the nitrate anion is highly mobile and difficult to immobilize, especially in relatively porous cement-based grout which has been used to date as a method for the immobilization of liquid waste, it presents a major obstacle to environmental clean-up initiatives. Thus, in an effort to contribute to the existing body of knowledge and enhance the efficacy of the NAC process, this research involved the experimental measurement of the rheological and heat transfer behaviors of the NAC product slurry and the determination of the optimal operating parameters for the continuous NAC chemical reaction process. Test results indicate that the NAC product slurry exhibits a typical non-Newtonian flow behavior. Correlation equations for the slurry's rheological properties and heat transfer rate in a pipe flow have been developed; these should prove valuable in the design of a full-scale NAC processing plant. The 20-percent slurry exhibited a typical dilatant (shear thickening) behavior and was in the turbulent flow regime due to its lower viscosity. The 40-percent slurry exhibited a typical pseudoplastic (shear thinning) behavior and remained in the laminar flow regime throughout its experimental range. The reactions were found to be more efficient in the lower temperature range investigated. With respect to leachability, the experimental final NAC ceramic waste form is comparable to the final product of vitrification, the technology chosen by DOE to treat these wastes. As the NAC process has the potential of reducing the volume of nitrate-based radioactive liquid waste by as much as 70 percent, it not only promises to enhance environmental remediation efforts but also effect substantial cost savings. ^

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The improvement of tropical tree crops using conventional breeding methods faces challenges due to the length of time involved. Thus, like most crops, there is an effort to utilize molecular genetic markers in breeding programs to select for desirable agronomic traits. Known as marker assisted breeding or marker assisted selection, genetic markers associated with a phenotype of interest are used to screen and select material reducing the time necessary to evaluate candidates. As the focus of this research was improving disease resistance in tropical trees, the usefulness of the WRKY gene superfamily was investigated as candidates for generating useful molecular genetic markers. WRKY genes encode plant-specific transcriptional factors associated with regulating plants' responses to both biotic and abiotic stress. ^ One pair of degenerate primers amplified 48 WRKY gene fragments from three taxonomically distinct, economically important, tropical tree crop species: 18 from Theobroma cacao L., 21 from Cocos nucifera L. and 9 from Persea americana Mill. Several loci from each species were polymorphic because of single nucleotide substitutions present within a putative non-coding region of the loci. Capillary array electrophoresis-single strand conformational polymorphism (CAE-SSCP) mapped four WRKY loci onto a genetic linkage map of a T. cacao F2 population segregating for resistance to witches' broom disease. Additionally, PCR primers specific for four T. cacao loci successfully amplified WRKY loci from 15 members of the Byttneriae tribe. A method was devised to allow the reliable discrimination of alleles by CAE-SSCP using only the mobility assigned to the sample peaks. Once this method was validated, the diversity of three WRKY loci was evaluated in a germplasm collection of T. cacao . One locus displayed high diversity in the collection, with at least 18 alleles detected from mobility differences of the product peaks. The number of WRKY loci available within the genome, ease of isolation by degenerate PCR, codominant segregation demonstrated in the F2 population, and usefulness for screening germplasm collections and closely related wild species demonstrates that the WRKY superfamily of genes are excellent candidates for developing a number of genetic molecular markers for breeding purposes in tropical trees. ^

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In isolation and characterization studies, expression level U1 and U2 snRNA isoforms were obtained from the 5th instar larval stage silk gland (SG). The DNA content of the SG cells is approximately 200,000-fold higher compared to the usual (2N) somatic cells of B. mori due to endoreduplication. In this study, the existence of U1 and U2 snRNA isoforms in the SG of the organism is investigated. Bombyx mori U1 and U2-specific RT-PCR libraries from the silk gland were generated. Five U1 and eight U2 isoforms were isolated and characterized. Nucleotide differences, structural alterations, as well as protein and RNA interaction sites were analyzed in these variants. For the U1 snRNA variants, they were compared to the previously reported BmN isoforms. In all these U-snRNA variants, polymorphic sites do not predominate at the core of known functional sequences, which were interspecifically conserved. Variant sites and inter-species differences are located in moderately conserved regions. Free energy (ΔG) values for the entire U1 and U2 snRNA secondary structures and for the individual stem/loops domains of the isoforms were generated and compared to determine their structural stability. This will be the first time that U1 and U2 variants are shown specific for a development stage (larval) other than embryonic or adult. ^ Using phylogenetic analysis, evolutionary trees were generated for the U1 and U2 snRNAs using animal, plant, protista and fungal species. The resulting trees were boostrapped for robustness and rooted with the self-splicing RNA group II intron sequence from the cyanobacterium Calothrix. Using phylogenetic analyses, possible structural and functional evolutionary interdependence between the U1 and U2 snRNAs was investigated. ^

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A pivotal component of hydrological restoration of the Florida Everglades is the improvement of water conveyance to Everglades National Park by the degradation of the current network of canals, roadways and levees. The Tamiami Trail (L29) road/canal complex represents a major barrier to natural water flows into the park and a variety of modification options for flow improvement are currently being explored, including the installation of spreader swales immediately downstream of culverts conveying water under Tamiami Trail from the L29 canal into Everglades National Park. In this study, we evaluated water column chemistry and wet-season diatom community structure to provide baseline information for use in future monitoring activities related to the proposed Tamiami Trail modifications. Water chemistry showed pronounced fluctuations in response to precipitation and anthropogenically mediated hydrological events. Differences in water quality variables among sites were dampened during periods of inundation, and became more pronounced during periods of low canal stage, suggesting the importance of small-scale mechanisms related to isolation of habitat patches. Diatom assemblages were unexpectedly speciose (127 taxa in 40 samples) compared to typical Everglades assemblages, and spatially heterogeneous in sites associated with concentric areas of dense vegetation immediately downstream of culverts. We also observed significant compositional dissimilarities among transects, indicating that culvert pool and north transect assemblages were substantially influenced by propagule input from the canal and areas to the north, while south transect sites were compositionally similar to typical sawgrass prairie diatom communities. Central transect sites were compositionally intermediate to their north and south counterparts. We propose that the position and spatial extent of this “transitional assemblage” is a sensitive indicator of subtle environmental change related to Tamiami Trail modifications.

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The new engine plant by General Motors (GM) in Joinville-SC, inaugurated on February 27th 2013, incorporates the most advanced automotive technology processes and broad compliance with environmental standards and energy efficiency. The initiatives implemented in this industrial plant include processes with 100% of recycled industrial waste (landfill free) and pioneer systems in energy efficiency and environmental protection, qualifying the plant to obtain the global certification of Leadership in Energy and Environmental Design (LEED). This industrial project reveals the strategic importance of the region and of Brazil in the growth of GM in the world, becoming a reference for studies and project evaluations of "green" factories in the automotive sector. The present study performs an exploratory research based on scientific publications, assessing the direct and indirect impacts on the business outcome, resulting from implementation of industrial serviceoriented sustainability of its operations, referred to in this article as "Green Factory”. We concluded that the adopted technologies focused on sustainability, study and development, represent a new step for the design of new plants and future expansions of the company in the region, combining low operating cost, low environmental impact and conservation of natural resources.

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This reports summarises research that began in March 2014 and was completed in October 2015 by an experienced inter-disciplinary research team from the Centre for Social Justice and Change and Psycho-Social Research Group, School of Social Sciences, the University of East London (UEL) and included Dr Yang Li from the Centre for Geo-Information Studies, UEL, for the first phase of the study. Tottenham ‘Thinking Space’ (TTS) was a pilot therapeutic initiative based in local communities and delivered by the Tavistock & Portman NHS Foundation Trust and funded by the London Borough of Haringey Directorate of Public Health. TTS aimed to improve mental health and enable and empower local communities. TTS was situated within a mental health agenda that was integral to Haringey’s Health and Wellbeing Strategy 2012-2015 and aimed to encourage people to help themselves and each other and develop confident communities. On the one hand TTS was well-suited to this agenda, but, on the other, participants were resistant to, and were trying to free themselves from labelling that implied ‘mental health difficulties’. A total of 243 meetings were held and 351 people attended 1,716 times. The majority of participants attended four times or less, and 33 people attended between 5 and 10 times and 39 people attended over 10 times. Attending a small number of times does not necessarily mean that the attendee was not helped. Attendees reflected the ethnic diversity of Tottenham; 29 different ethnic groups attended. The opportunity to meet with people from different cultural backgrounds in a safe space was highly valued by attendees. Similarly, participants valued the wide age range represented and felt that they benefited from listening to inter-generational experiences. The majority of participants were women (72%) and they were instrumental in initiating further Thinking Spaces, topic specific meetings, the summer programme of activities for mothers and young children and training to meet their needs. The community development worker had a key role in implementing the initiative and sustaining its growth throughout the pilot period. We observed that TTS attracted those whose life experiences were marked by personal struggle and trauma. Many participants felt safe enough to disclose mental health difficulties (85% of those who completed a questionnaire). Participants also came seeking a stronger sense of community in their local area. Key features of the meetings are that they are democratic, non-judgemental, respectful, and focussed on encouraging everyone to listen and to try to understand. We found that the therapeutic method was put in place by high quality facilitators and health and personal outcomes for participants were consistent with those predicted by the underpinning psychoanalytical and systemic theories. Outcomes included a reduction in anxieties and improved personal and social functioning; approximately two thirds of those who completed a questionnaire felt better understood, felt more motivated and more hopeful for the future. The overwhelming majority of survey respondents also felt good about contributing to their community, said that they were more able to cooperate with others and accepting of other cultures, and had made new friends. Participants typically had a better understanding of their current situation and how to take positive action; of those who completed a questionnaire, over half felt more confident to seek support for a personal issue and to contact services. Members of TTS supported each other and instilled hope and build community-mindedness that reduced social isolation.

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Economic losses resulting from disease development can be reduced by accurate and early detection of plant pathogens. Early detection can provide the grower with useful information on optimal crop rotation patterns, varietal selections, appropriate control measures, harvest date and post harvest handling. Classical methods for the isolation of pathogens are commonly used only after disease symptoms. This frequently results in a delay in application of control measures at potentially important periods in crop production. This paper describes the application of both antibody and DNA based systems to monitor infection risk of air and soil borne fungal pathogens and the use of this information with mathematical models describing risk of disease associated with environmental parameters.