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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

THE DEVELOPMENT OF A METAL PLATE TEST REACTOR FOR STUDYING REACTION KINETICS ON CATALYTICALLY COATED HEAT TRANSFER COMPONENTS

KHOSRAVI, AIDA 28 September 2012 (has links)
A novel catalytic metal plate test reactor was designed, built and commissioned. The overall dimensions of the whole assembly were 215 mm long 75 mm wide 60 mm deep. A strip of stainless steel with dimensions of 150 mm long 15 mm wide 1.59 mm thick was partly coated with catalyst and sealed between the two reactor parts. The design provided a single channel flow pattern that could be easily modeled to extract kinetic parameters. A key feature of the reactor design was effective heat transfer to promote isothermal operation. A series of thermocouples was incorporated into the reactor to measure the temperature profile along the reactor. Performance of the reactor was verified using a well characterized commercially available Cu/Zn/Al2O3 catalyst from BASF. The goal of this experimentation was to determine the conversion, rate constant and activation energy for methanol steam reforming and compare these with previously published measurements. Methanol conversion was measured at slightly higher than atmospheric pressure at temperatures of 220, 240 and 260 °C. Steam to water ratio of feed was maintained at one during the experimental program. The feed rate of methanol was varied to obtain a catalyst to feed ratio between 6 and 20 kgs mol-1. The composition of reformate and methanol conversion were studied with temperature and flow rate of the feed. An increase from 27.68 to 41.61% in methanol conversion was observed increasing the reaction temperature from 220 to 240°C. An irreversible first order rate constant was calculated using the experimentally measured conversion and space time. The apparent activation energy (Ea) based on a first order plug flow design operation was 96±4 k.J.mol-1 and agreed well with the values of 77-105.1 kJmol-1 reported in the literature. / Thesis (Master, Chemical Engineering) -- Queen's University, 2012-09-28 12:39:38.392
2

Determination of maximum fuel plate temperature in a light water moderated research reactor with central water void

Broadman, Gene Arnold. January 1963 (has links)
Thesis (M.S. in Engineering Science)--University of California, June 1963. / TID-4500 (19th Ed.). Bibliography: l. 70-71.
3

Sistema de obtencao de um pre-projeto otimizado de um nucleo de um reator nuclear

MAI, LUIZ A. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:32:47Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:08:32Z (GMT). No. of bitstreams: 1 03473.pdf: 1345873 bytes, checksum: c84cb3f38a6cd9b74002f62ae4817f88 (MD5) / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
4

Sistema de obtencao de um pre-projeto otimizado de um nucleo de um reator nuclear

MAI, LUIZ A. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:32:47Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:08:32Z (GMT). No. of bitstreams: 1 03473.pdf: 1345873 bytes, checksum: c84cb3f38a6cd9b74002f62ae4817f88 (MD5) / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
5

Reactor disposal evaluation at Sol Voltaics

Nilsson, Jens, Nilsson, Johan January 2016 (has links)
The purpose of this project was to map the current method for decommissioning / disposing of the Nano-wire reactor at Sol Voltaics. Additionally, alternatives should be suggested based on the findings during the mapping processes and the subsequent analysis. The aim of the presented alternatives was to improve the current workflow for reactor decommissioning based on five identified areas; Rules and Regulations; Environmental aspects; Safety aspects; Economical aspects and Logistical aspects. The existing disposal procedure was divided into six steps. The first step involves a purging procedure to make sure no hazardous gases remain in the reactor. The second step is to dismantle and seal the reactor. The third step is to move the reactor to a loading dock. The fourth step is the transport between Active Biotech in Lund and Sydblästring AB in Malmö. The fifth step is the disassembly and cleaning process of the reactor parts, including waste management. The sixth and final step is to move the cleaned parts to SYSAV in Malmö for final disposal. Finally, Rules and Regulations as well as Safety aspects were identified as having partial improvement potential. Ideas for possible alternatives in these areas was devised and analyzed according to all five areas to make sure that the improvements in one area would not bring undesirable shortcomings in another.
6

Desenvolvimento de sistema computacional para planejamento e controle da manutenção do reator IEA-R1 / Development of a computacional program to planning and control of the IEA-R1 reactor maintenance

MARTINS, MAURO O. 23 July 2015 (has links)
Submitted by Claudinei Pracidelli (cpracide@ipen.br) on 2015-07-23T10:51:27Z No. of bitstreams: 0 / Made available in DSpace on 2015-07-23T10:51:27Z (GMT). No. of bitstreams: 0 / Dissertação (Mestrado em Tecnologia Nuclear) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP
7

Desenvolvimento de sistema computacional para planejamento e controle da manutenção do reator IEA-R1 / Development of a computacional program to planning and control of the IEA-R1 reactor maintenance

MARTINS, MAURO O. 23 July 2015 (has links)
Submitted by Claudinei Pracidelli (cpracide@ipen.br) on 2015-07-23T10:51:27Z No. of bitstreams: 0 / Made available in DSpace on 2015-07-23T10:51:27Z (GMT). No. of bitstreams: 0 / A manutenção é uma atividade essencial em reatores nucleares. Os componentes de sistemas de segurança de uma instalação industrial devem ter uma baixa probabilidade de falha, especialmente se houver um elevado risco de acidentes que podem causar danos ambientais. Em instalações nucleares, a presença de sistemas de segurança são uma especificação técnica e uma exigência para a sua licença de funcionamento. De forma a gerenciar todo o fluxo de informações provenientes das manutenções do Reator IEA-R1 foi desenvolvido um sistema computacional, que além de planejar e controlar toda a manutenção mantém atualizados documentos e registros para salvaguardar a qualidade e garantir a segurança na operação do Reator IEA-R1. O sistema computacional possui níveis de acesso e apresenta relatórios detalhados de todas as manutenções previstas e executadas, e também um histórico individual de cada equipamento durante sua vida útil na instalação. O trabalho apresenta todas as etapas de desenvolvimento do sistema, sua descrição, compatibilidades, aplicação, vantagens e resultados obtidos experimentalmente. / Dissertação (Mestrado em Tecnologia Nuclear) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP
8

Optimization of Batch and Semi-batch Reactors

Pahija, E., Manenti, F., Mujtaba, Iqbal M. January 2013 (has links)
no / Batch and semi-batch reactors are widely used for fine chemical productions. The target in the fine chemical industry is to produce a high quality product and operational optimization is the key-element to match it. This work investigates how batch and semi-batch reactors can be optimized in order to increase the yield of a desired product. Optimization problem is formulated and applied to calculate the optimal operating parameters such as the reactor temperature and the feed flow rate. Comparison and considerations on the two reactor configurations are given.
9

Investigating the Validity of UV Reactor Additivity

Young, Patrick 11 December 2013 (has links)
Ultraviolet (UV) light reactors or banks are often arranged in series in order to meet microbial inactivation credit requirements. It has been assumed that UV doses given by each reactor in series are mathematically additive, though work done to substantiate the hypothesis has been inconsistent. Based on previously developed theory of reactor additivity and the reactor additivity factor (RAF), three types of UV reactors are modelled using computational fluid dynamics and their RAFs are computed. It is noted that the assumption of perfect mixing may not be valid depending on the distance between reactors in series. It is discussed that the original formulation of the RAF is inadequate when dealing with wastewater. It is shown unexpectedly that even with perfect mixing performance, worse than additivity would be achieved. A new performance factor (PF) is introduced and the implications of this are further discussed in the context of UV reactor validation.
10

Investigating the Validity of UV Reactor Additivity

Young, Patrick 11 December 2013 (has links)
Ultraviolet (UV) light reactors or banks are often arranged in series in order to meet microbial inactivation credit requirements. It has been assumed that UV doses given by each reactor in series are mathematically additive, though work done to substantiate the hypothesis has been inconsistent. Based on previously developed theory of reactor additivity and the reactor additivity factor (RAF), three types of UV reactors are modelled using computational fluid dynamics and their RAFs are computed. It is noted that the assumption of perfect mixing may not be valid depending on the distance between reactors in series. It is discussed that the original formulation of the RAF is inadequate when dealing with wastewater. It is shown unexpectedly that even with perfect mixing performance, worse than additivity would be achieved. A new performance factor (PF) is introduced and the implications of this are further discussed in the context of UV reactor validation.

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