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Uso de floculador hidráulico de manta de lodo acoplado a flotador por ar dissolvido no tratamento de água de abastecimento /Paz Júnior, Gilberto José da. January 2009 (has links)
Orientador: Edson Pereira Tangerino / Banca: Dib Gebara / Banca: Carlos Gomes da Nave Mendes / Resumo: Novas tecnologias para o tratamento de água vêem sendo desenvolvidas e suas combinações podem apresentar bons resultados principalmente quando submetidas a variações sazonais de origem natural e antropicas. A crescente poluição dos corpos d'água causa florescimentos de algas e cianobactérias nos mananciais, com aparecimento de sabor e odor na água bruta, podendo ocorrer também a liberação de toxinas pelas cianobactérias. Os processos de tratamento de água convencionais têm apresentado deficiências quanto à remoção de cianobactérias e cianotoxinas, principalmente quanto ao aspecto de remoção das células viáveis e na capacidade de remover as toxinas extracelulares. As cianobactérias retidas no lodo dos decantadores representam riscos à qualidade final da água tratada. O presente projeto de pesquisa consistiu em experiência com floco-decantador de manta de lodo acoplado a flotador por ar dissolvido, formando um conjunto composto pelos dois tipos de equipamentos ou tecnologias e ainda com dispositivo limitador de manta. O objetivo da pesquisa foi avaliar o desempenho da instalação proposta quando submetida a variações da qualidade da água bruta, principalmente quando submetido à sobrecarga de algas e cianobactérias, simulando possíveis florações nos mananciais. Os resultados dos ensaios no modulo experimental com água natural apresentaram remoção satisfatória de turbidez , com valores abaixo de 3,0 uT da água floco-floto-decantada e em torno de 0,1 uT da água filtrada. Os ensaios realizados com água natural com presença elevada de algas e cianobactérias, evidenciaram a importância da unidade de flotação, com remoção de clorofila_a de 82% na água decantada/flotada e próximo de 99% na água filtrada, em relação à água bruta, sendo que a turbidez manteve-se abaixo de 3 uT na saída do modulo floco-floto-decantador e a turbidez... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: New technologies for water treatment have been developed and their combinations can produce good results especially when subjected to seasonal variations of natural and anthropogenic. The increasing pollution of water bodies causes blooms of algae and cyanobacteria in water sources, with the appearance of taste and odor in raw water, but may also occur the release of toxins by cyanobacteria. The processes of conventional water treatment have shown deficiencies in the removal of cyanobacteria and cyanotoxins, especially on the aspect of removal of viable cells and the ability to remove extracellular toxins. Cyanobacteria retained in the sludge of the sedimentation tanks pose to the final quality of treated water. This research project was to experiment with floc-settling sludge blanket coupled to dissolved air flotation, forming a group composed of two types of equipment or technology, and with relief device blanket. The research aimed to evaluate the performance of the proposed development when subjected to variations in raw water quality, especially when subjected to the overload of algae and cyanobacteria to simulate possible blooms in the springs. The results of tests on an experimental module with natural water showed satisfactory removal of turbidity, with values below 3 uT decanted and around 0,1 uT filtered water. Tests conducted with water with high presence of algae and cyanobacteria, have highlighted the importance of unity flotation Chlorophyll "a" with removal of 82% in the decanted water / rappel and around 99% in filtered water compared to raw water, and the turbidity remained below 3 uT the output of modulo-flake-floto sedimentation and turbidity of filtered water was below 0,6 uT. The limiting device of the ground and periodic removal of sludge, decreased the retention time of the cells retained in the sludge which may have prevented the release of toxins into the water... (Complete abstract click electronic access below) / Mestre
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[en] DEVELOPMENT OF AN IN SITU THERMAL DESORPTION SYSTEM FOR THE REMEDIATION OF PETROLEUM HIDROCARBON CONTAMINATED MATERIALS / [pt] DESENVOLVIMENTO DE UM SISTEMA DE DESSORÇÃO TÉRMICA IN SITU PARA REMEDIAÇÃO DE MATERIAIS CONTAMINADOS POR HIDROCARBONETOS DE PETRÓLEOPATRICIO JOSE MOREIRA PIRES 01 October 2004 (has links)
[pt] O presente trabalho avaliou a eficácia da dessorção térmica
in situ em remediar materiais contaminados por
hidrocarbonetos de petróleo em refinarias. Paralelamente,
foi projetado e construído um novo sistema modular para ser
empregado sob dutovias para remediação de britas
contaminadas. Os resultados do programa experimental
revelaram ser possível a remediação de pavimentos de
concreto contaminados por óleo combustível. A aplicação de
calor na superfície do pavimento reduziu em até 65 por cento a sua
resistência, porém propiciou a restauração de sua cor
original. Verificou-se que os resíduos do processo, após
análises mineralógicas por difração de raios X e químicas
por espectroscopia de fluorescência, apresentavam uma
composição muito semelhante ao solo empregado como material
de construção dos aterros da refinaria, sugerindo que o
resíduo possa ser advindo de transporte eólico. O sistema
desenvolvido no presente trabalho apresentou um
desempenho satisfatório. Verificou-se a necessidade de
aeração do material remediado para eliminar a produção de
coque. Adicionalmente, observou-se a importância de um bom
isolamento térmico para minimizar o consumo energético e
impedir a propagação de calor e das emissões para a
atmosfera. As emissões geradas pelo aquecimento consistiam
de olefinas e parafinas que podem ser devidamente tratadas
pelo oxidador térmico. / [en] This dissertation assessed the adequacy of in situ thermal
desorption (istd)
in cleaning oil contaminated debris from Refineries. A new
modulated istd system
was designed and built in order to remediate oiled cobbles
under pipeways.
The experimental results revealed the possibility of
cleaning concrete
pavements contaminated by heavy oil. The thermal desorption
process restored
their original color but reduced their resistance up to
65 percent. It was observed that
the resulting debris, after mineralogical analyses by X-ray
diffraction and
chemical analysis by X-Ray fluorescence, have a similar
composition to the soil
employed in the fills throughout the Refinery, indicating
that the debris could well
have been transported by the wind.
The system devised here had a satisfactory performance. It
was observed
the necessity of aeration during the treatment in order to
avoid the production of
coke. Additionally, it was also observed the importance of
a good thermal
insulation in order to minimize power consumption and the
propagation of heat
and gas emissions to the atmosphere.
The gases emissions consisted mainly of olefins and
paraffins that had
been reasonably been treated by the thermal oxidizer
devised herein.
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Deltack, Blanket StudyRandström, Monica January 2002 (has links)
There are two objectives of this study.The first one was to study the new instrument Deltack fromPrufbau, and with the new knowledge, study the interaction between blanket and paper.Deltack is a new instrument to measure the ink splitting force. Blankets from an earlier study doneby GATF have been montered on 12 different Deltack print forms and those have together with Deltackbeen the base for this project.This study together with information from GATF’s study shows that some of the blankets have ahigher capability to adsorb ink. Those blankets generate a sharper shape on the force curve, they havea lower dot gain, but they print not as good solid.
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Assessment of a Modified Double Agar Layer Method to Detect Bacteriophage for Assessing the Potential of Wastewater Reuse in Rural BoliviaHadley, Sakira N. 01 January 2013 (has links)
Water scarcity is a global concern that impacts many developing countries, forcing people to depend on unclean water sources for domestic, agricultural, and industrial needs. Wastewater is an alternative water source that contains nutrients needed for crop growth. Wastewater reuse for agriculture can cause public health problems because of human exposure to pathogens. Pathogen monitoring is essential to evaluate the compliance of wastewater with established World Health Organization (WHO) and U.S. Environmental Protection Agency (EPA) wastewater reuse guidelines. Indicator organisms are commonly used to detect pathogens in water and wastewater because they are quick and easy to measure, non-pathogenic, and have simple and inexpensive methods of detection.
The objective of this research was to develop a modified double agar layer assay method that can be conducted in the field to quantify bacteriophage to assess the quality of wastewater for agricultural reuse. Results from the modified double agar layer assay were used to investigate the potential of somatic coliphage as an indicator organism for assessing the potential presence of enteric viruses in developing world treated wastewater, and to use the criteria of a good indicator organism to compare the potential of two commonly used indicator organisms, somatic coliphage and fecal coliforms, as an indicator of enteric viruses in wastewater.
A modified EPA double agar layer method was developed and deployed in a developing world rural community to effectively quantify the concentration of somatic coliphage in a community managed wastewater treatment system composed of a Upflow Anaerobic Sludge Blanket (UASB) reactor followed by two maturation lagoons. The modified method served as a good indicator of enteric viruses in the water. Somatic coliphages were easily detected and quantified in the field setting using a modified double agar layer method. Somatic coliphage was found to be a potential indicator for enteric viruses rather than fecal coliforms because of their similarity in characteristics and resistances to wastewater treatment. The concentration of somatic coliphage was only reduced by 1.05 log units across the two series maturation lagoon system. Previous literature suggested removal would range from 2.1 to 4.6 log units. Influent wastewater (previously treated by an UASB reactor) had a concentration of 4.38 E+06 PFU/ 100 mL (standard deviation = ±3.7E+06, n = 9) and the treated effluent contained 3.90 E+05 PFU/100 mL (standard deviation = ± 4.5E+05, n = 8) of somatic coliphages. Results suggest that somatic coliphage is a good potential indicator for enteric viruses in wastewater but further research needs to be done.
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Preservation techniques and carbon and nitrogen growth enhancement of batch cultivated UASB granulesCameron, Michelle 12 1900 (has links)
Thesis (MSc Food Sc )--Stellenbosch University, 2000. / ENGLISH ABSTRACT: The potential use of the upflow anaerobic sludge blanket (UASB) bioreactor is
limited by the extended start-up periods due to the time-consuming granulation
process and the fact that seeding inoculum is not freely available in most
developing countries like South Africa. The mass cultivation of granules would
provide the waste water treatment industry with suitable seeding inoculum and,
therefore, an efficient waste water treatment option would be more easily
available. By applying 'stress' conditions on a bioreactor system seeded with raw
anaerobic sludge, the population dynamics of the anaerobic community change
and the acidogens start to produce extracellular polymers, which in turn enhance
the granulation process by providing a matrix for the bacterial cells to adhere to.
These "environmental stress" conditions include changes in the C:P:N ratio's. The
aim of this study was, therefore, to assess the impact of different carbon and
nitrogen sources on the enhancement of granulation in a batch system, and to
determine the best preservation technique in terms of retainment of activity.
It was found that the carbon source and concentration had a significant
influence on batch granule enhancement. Low concentrations (2.g.l ̄ ¹)
of glucose
gave the best granule enhancement over a 14 day incubation period. Fruit
cocktail effluent was found to be a cheap and effective carbon source for batch
granule cultivation. It was found that different nitrogen sources did not have the
same impact on granule enhancement, however, urea, at all concentrations
tested, gave the best granule enhancement.
A major problem encountered during the study was the standardisation of
the inoculum. Significant granule enhancement comparisons between the
different carbon sources were impeded by the lack of a suitable and reliable form
of sludge standardisation. Future research needs to address this problem of the
standardisation of the sludge inoculum as this would lead to more kinetically
comparable results.
Mass granule culturing will require granule preservation without risking the
loss of activity. In the second study, six different preservation techniques and
storage periods were evaluated in terms of the retainment of activity. These
involved freeze-drying, vacuum freeze-drying, vacuum-drying, freezing, cold storage and room temperature preservation. Activity testing was used for
comparing the efficiency of the different preservation techniques in terms of the
tempo of biogas and methane production. Freeze-drying the granules, with
storage for up to 90 days was found to give the best retainment of activity,
followed by vacuum freeze-drying. The room temperature preserved samples
showed a sudden increase in activity by day 120, which could possibly be
explained by cell hydrolysis of the granules after day 90.
The highest activity was achieved after 10 h of incubation, and it was,
therefore, suggested that activity testing for evaluation purposes should use an
incubation time of only 10 h. Furthermore, only the basic test medium with added
glucose should be used for activity testing as it was observed that the addition of
lactate and acetic acid played no decisive role in determining the level of activity of
the granules.
This study recommends the use of low concentrations of glucose for
optimum granule enhancement during the mass cultivation of granules, and the
addition of low concentrations of lactate to ensure a stable system with no
acidification. It is also advisable to use a standardised sludge inoculum, as this
will allow more efficient comparisons. Freeze-drying is recommended as
preservationtechnique as this technique showed the best retainment of activity. A
storage period of 90 days is, however, too short to be of much use for the industry.
This will have to be investigated, together with the phenomenon of increased
activity after 90 days as shown by the room temperature preserved granules. / AFRIKAANSE OPSOMMING: Die potensiële gebruik van die "uptflow anaerobic sludge blanket" (UASB)
bioreaktor word beperk deur verlengde aansitprosedure as gevolg van die
tydsame granulasieproses en die feit dat geskikte inokulums nie vrylik beskikbaar
is in die meeste ontwikkelende lande, bv. Suid-Afrika nie. Die massa-kweking van
granules sal die afvalwater-industrie voorsien van 'n geskikte inokulum, en
sodoende 'n effektiewe opsie vir die behandeling van afvalwater beskikbaar stel.
Deur die aanwending van "stres" toestande op 'n reaktor, wat geinokuleer is met
rou anaerobe slyk, vind daar 'n verandering in die samestelling van die anaerobe
populasie plaas. Die laktaat-benuttende asidogene begin om ekstrasellulêre
polisakkariede te produseer wat die granulasieproses versnel deur 'n matriks te
voorsien waaraan die bakteriële selle kan heg. Hierdie "omgewings stres"
toestande sluit veranderinge in die C:P:N verhoudings in. Die doel van hierdie
studie was om die invloed van verskillende koolstof- en stikstofbronne op die
vermeerdering van granules te bepaal, asook om die beste preserveringstegniek
in terme van die behoud van aktiwiteit te bepaal.
Daar is gevind dat die koolstofbron en konsentrasie 'n betekenisvolle
invloed op granule-vermeerdering het. Lae konsentrasies glukose (2 g.I ̄ ¹) het tot
die grootste vermeerdering in granules oor 'n 14 dae inkubasieperiode gelei.
Vrugtekelkie-afvalwater is geidentifiseer as 'n goedkoop en effektiewe koolstofbron
wat ook gebruik kan word vir die kweking van granules. Voorts is gevind dat die
stikstofbron en konsentrasie nie so 'n groot invloed op granule-vermeerdering het
nie. Urea het nietemin die beste granule-vermeerdering vir al die konsentrasies
wat getoets is, gegee.
Standaardisasie van die inokulum was 'n groot probleem gedurende die
studie. Betekenisvolle vergelykings tussen die granule-vermeerderings verkry met
die verskeie groeimedia is bemoeilik deur die afwesigheid van 'n geskikte en
betroubare standaardisasie-metode. Toekomstige navorsing moet hierdie
probleem aanspreek aangesien dit sal lei tot meer kineties vergelykbare resultate.
Massa-kweking van granule sal 'n metode van granule-preservering vereis
sonder enige verlies van aktiwiteit. In die tweede studie is ses verskillende
preserverings-tegnieke en opbergings-periodes in terme van die behoud van aktiwiteit geëvalueer. Die tegnieke sluit in: vriesdroging; vakuum-vriesdroging;
vakuumdroging; bevriesing; koelopberging en kamertemperatuur-preservering.
Aktiwiteitstoetsing is gebruik vir die vergelyking van die effektiwiteit tussen die
verskillende preserverings-tegnieke in terme van die tempo van biogas- en
metaanproduksie. Die granules wat met behulp van die vriesdroogtegniek
gepreserveer is, het die beste behoud van aktiwiteit getoon, gevolg deur die
vakuum-gevriesdroogde granules. Die monsters wat by kamertemperatuur
gepreserveer is, het 'n skielike toename in aktiwiteit na 120 dae van opberging
getoon en 'n moontlike verklaring vir hierdie verskynsel kan sel-hidrolise van die
granules na 90 dae van opberging wees.
Die meeste aktiwiteit is behaal na 'n 10 h inkubasietyd, en dus word hierdie
inkubasietyd aanbeveel indien aktiwiteitstoetse vir evaluerings-doeleindes gedoen
word. Verder word aanbeveel dat slegs die glukose-verrykte basiese toetsmedia
vir aktiwiteitstoetsing gebruik word aangesien die byvoeging van laktaat en
asynsuur geen noemenswaardige rol speel in die bepaling van die vlak van
aktiwiteit van die granules nie.
Hierdie studie beveel die gebruik van lae glukosekonsentrasies aan vir
optimale vermeerdering van granules tydens die massakweking daarvan, asook
die byvoeging van lae konsentrasies laktaat om 'n stabiele sisteem met geen
versuring te verseker. Die gebruik van 'n gestandaardiseerde slyk-inokulum word
sterk aanbeveel aangesien dit meer vergelykbare resultate lewer. Vriesdroging
(as preserveringstegniek) het die beste behoud van aktiwiteit in die granules
getoon en word dus as preserveringstegniek aanbeveel. 'n Opbergingsperiode
van 90 dae is egter te kort om van veel waarde vir die industrie te wees. Hierdie
probleem, asook die verskynsel van 'n verhoging in aktiwiteit na 90 dae van die
granules wat by kamertemperatuur gepreserveer is, moet verder ondersoek word.
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Uso de floculador hidráulico de manta de lodo acoplado a flotador por ar dissolvido no tratamento de água de abastecimentoPaz Júnior, Gilberto José da [UNESP] 09 October 2009 (has links) (PDF)
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pazjunior_gj_me_ilha.pdf: 2578429 bytes, checksum: 46851cc20a1e31876058f21101609b1f (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Novas tecnologias para o tratamento de água vêem sendo desenvolvidas e suas combinações podem apresentar bons resultados principalmente quando submetidas a variações sazonais de origem natural e antropicas. A crescente poluição dos corpos d’água causa florescimentos de algas e cianobactérias nos mananciais, com aparecimento de sabor e odor na água bruta, podendo ocorrer também a liberação de toxinas pelas cianobactérias. Os processos de tratamento de água convencionais têm apresentado deficiências quanto à remoção de cianobactérias e cianotoxinas, principalmente quanto ao aspecto de remoção das células viáveis e na capacidade de remover as toxinas extracelulares. As cianobactérias retidas no lodo dos decantadores representam riscos à qualidade final da água tratada. O presente projeto de pesquisa consistiu em experiência com floco-decantador de manta de lodo acoplado a flotador por ar dissolvido, formando um conjunto composto pelos dois tipos de equipamentos ou tecnologias e ainda com dispositivo limitador de manta. O objetivo da pesquisa foi avaliar o desempenho da instalação proposta quando submetida a variações da qualidade da água bruta, principalmente quando submetido à sobrecarga de algas e cianobactérias, simulando possíveis florações nos mananciais. Os resultados dos ensaios no modulo experimental com água natural apresentaram remoção satisfatória de turbidez , com valores abaixo de 3,0 uT da água floco-floto-decantada e em torno de 0,1 uT da água filtrada. Os ensaios realizados com água natural com presença elevada de algas e cianobactérias, evidenciaram a importância da unidade de flotação, com remoção de clorofila_a de 82% na água decantada/flotada e próximo de 99% na água filtrada, em relação à água bruta, sendo que a turbidez manteve-se abaixo de 3 uT na saída do modulo floco-floto-decantador e a turbidez... / New technologies for water treatment have been developed and their combinations can produce good results especially when subjected to seasonal variations of natural and anthropogenic. The increasing pollution of water bodies causes blooms of algae and cyanobacteria in water sources, with the appearance of taste and odor in raw water, but may also occur the release of toxins by cyanobacteria. The processes of conventional water treatment have shown deficiencies in the removal of cyanobacteria and cyanotoxins, especially on the aspect of removal of viable cells and the ability to remove extracellular toxins. Cyanobacteria retained in the sludge of the sedimentation tanks pose to the final quality of treated water. This research project was to experiment with floc-settling sludge blanket coupled to dissolved air flotation, forming a group composed of two types of equipment or technology, and with relief device blanket. The research aimed to evaluate the performance of the proposed development when subjected to variations in raw water quality, especially when subjected to the overload of algae and cyanobacteria to simulate possible blooms in the springs. The results of tests on an experimental module with natural water showed satisfactory removal of turbidity, with values below 3 uT decanted and around 0,1 uT filtered water. Tests conducted with water with high presence of algae and cyanobacteria, have highlighted the importance of unity flotation Chlorophyll “a” with removal of 82% in the decanted water / rappel and around 99% in filtered water compared to raw water, and the turbidity remained below 3 uT the output of modulo-flake-floto sedimentation and turbidity of filtered water was below 0,6 uT. The limiting device of the ground and periodic removal of sludge, decreased the retention time of the cells retained in the sludge which may have prevented the release of toxins into the water... (Complete abstract click electronic access below)
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Ampliação de escala de um floco decantador de manta de lodo no tratamento de água de abastecimentoCavazzana, Tarso Luís [UNESP] 26 May 2006 (has links) (PDF)
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cavazzana_tl_me_ilha.pdf: 2979174 bytes, checksum: 3a1c33ad1723fd5eb6eef680e02d054b (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Na busca de avanços na concepção de uma Estação de Tratamento de Água (ETA) mais eficiente construiu-se, estudou-se e testou-se um Módulo Floco Decantador de Manta de Lodo (MFDML) - escala modelo. Essa busca contou com várias etapas e processos que envolveram uma ampla e variada pesquisa bibliográfica para a formação de idéias que foram ou poderão ser colocadas em prática para melhores calibração e verificação. Os avanços no MFDML forneceram resultados que motivaram seu estudo em escala de protótipo, denominado Sistema Floculador de Manta de Lodo (SFML) na forma de um Protótipo Modular Compacto (PMC) automatizado que pudesse ser operado de forma integrada aos diversos monitoramentos dos recursos hídricos. As idéias pesquisadas e estudadas geraram metodologias de cálculo que permitem a utilização prática do SFML, obtenção prévia de dosagens a partir de jar-test, estimativa da quantidade de lodo formada e estabelecimento de correlações qualitativas para aumento de escala. O SFML possui uma tecnologia com taxas de decantação 10 vezes maior que as tecnologias atuais (400m 3 /m 2 /dia) associados a bons resultados em termos de remoção de sólidos suspensos e dissolvidos, com turbidez da água decantada da ordem de 3uT e da filtrada de 0,1uT. No entanto, um maior desenvolvimento dessa nova tecnologia poderá ocorrer no âmbito científico-tecnológico conforme as necessidades e o despertar de idéias para contemplá-las. Assim, a busca por conhecimentos e melhoramentos científico-tecnológicos é um processo dinâmico, o qual envolve tempo, dedicação e continuidade das pesquisas. / On improvements search of the Water Treatment Plant more efficient conception was build, studied and tested a Sludge Blanket Flocculate Setter Modular Model. This search has been several processes and steps involved a varied and ample bibliographic search for ideas formation that was or will be set in practice for true verification and calibration. The improvements at the Sludge Blanket Flocculate Setter Modular Model gave results have motivated its prototype scale study, called Sludge Blanket Flocculator System in a Automated Compact Modular Prototype that could be operated in a integrated way with both waters resources managements and monitoring. These ideas generated calculation methodologies that may the Sludge Blanket Flocculator System for practice utilization, previous of dosages whith jar-test, formed sludge quantity estimate and scale increase correlations qualitative establishment. The Sludge Blanket Flocculator System owns a technology with settling rates 10 larger times than the current technologies (400m 3 /m 2 /dia) associates the good results in terms of suspended and dissolved solid removal, with water turbidity about 3uT and of the filtrated about 0,1uT. However, a more development of this new methodology may happen in a scientific-technology environ accord to the ideas necessities and emerge to get it. Thus, technologies-scientifics improvements and knowledge search is a dynamic process, which involves the research spend time, dedication and keep on of these.
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The Role of Victims’ Self-Efficacy in Perceptions of Blanket Amnesty and Engagement in Transitional Justice Processes: : May 27 Massacre, 1977, and The Blank Amnesty in AngolaG.Pinto, Diana January 2021 (has links)
How do victims of violence perceive blanket amnesties as part of transitional justice mechanisms in war-torn societies? The amnesty law is critical for conflict resolutions and post-conflict reconciliation processes. Governments and third parties use amnesties as a transitional justice instrument to end the violence because it ensures that conflict leaders will accept to engage in peace talks. However, a blanket amnesty restrains the victims’ narratives of past atrocities in the transitional justice process in exchange for peace. The amnesty in Angola illustrates this policy. The attempt to balance past and future avoids the risks of too much truth-telling from breaking peace negotiations. In a situation where peace and justice compete, this paper considers the victims as agents in the process. To this end, I enquire about the victims’ views about blanket amnesty. To find out, I explore the victims’ perceptions of the blanket amnesty in Angola and their engagement in transitional justice processes through their self-awareness. Specifically, how they apprehend their capabilities and social-political environment opportunities to change. For this purpose, I used Bandura’s self-efficacy theory of human agency to glean the victims’ consciousness of the political environment and capabilities. I argue that the victims’ self-efficacy level determines their perceptions of blanket amnesty and engagement as part of the transitional justice process that inflicts such an overwhelming impact on their lives. This study offers a micro-level interdisciplinary perspective to the transitional justice study field.
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Comfort behaviour in children : a psychological educational perspectiveKalyan, Santosh Vinita 11 1900 (has links)
This study addresses young children's involvement with comfort objects, including why children have them, how they are used, when attachments to such objects are cause for concern and how teachers and parents can respond to promote the young child's development.
The child's becoming and development is examined in this study. The researcher also reviews major transitional object theories in terms of origin, development and psychological meaning.
This study aims to explore this phenomenon from a psychological - educational perspective and to formulate a set of guidelines for parents and professionals whose children use comfort
behaviour.
Information was collated from case studies, a questionnaire and a detailed study of literature. / Psychology of Education / M. Ed. (Guidance and Counselling)
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Microbial community analysis of a UASB reactor and application of an evolutionary algorithm to enhance wastewater treatment and biogas productionEnitan, Abimbola Motunrayo January 2015 (has links)
Submitted in complete fulfillment for the degree of Doctor of Philosophy (Biotechnology), Durban University of Technology, Durban, South Africa, 2015. / Anaerobic digestion, a proven and highly efficient biological process for treating industrial wastewater and biogas generation is an underutilized technology in South Africa. Some of the industries that have on-site anaerobic reactors tend to face problems in operating these reactors due to poor understanding of the process and implementation of the technology. This has resulted in high pollutant loads in their final effluents and low energy recovery. In this study, an on-site full–scale upflow anaerobic sludge blanket (UASB) reactor treating brewery wastewater was extensively monitored in order to evaluate the efficiency in terms of effluent quality, biogas production and microbial structure. Furthermore, developed and adopted kinetic models were used to optimize the performance of the full–scale UASB reactor using a combined Pareto differential evolution (CPMDE) algorithm.
A preliminary analysis of the raw wastewater has shown that the wastewater produced from the brewery industry was high in organic matter with a total chemical oxygen demand (COD) between 1096.41 to 8926.08 mg/L. The average removal efficiency of COD from the UASB reactor after treatment was 79% with a methane (CH4) production of 60-69% at temperature ranges of 28-32˚C and hydraulic retention time (HRT) of 12 h within the optimal pH range for anaerobic bacteria (6.6 and 7.3) under various organic loading rates. However, the results also showed an increase in total suspended solids (TSS), nitrogen (N2), ammonia (NH3) and orthophosphate concentrations when comparing the influent to the effluent, which indicated the necessity for further optimization of the reactor condition in order to reduce these effluent parameters to acceptable standards and to increase CH4 production.
In order to optimize the process, a thorough understanding of microbial interaction was essential. A combination of different molecular techniques viz., fluorescence in–situ hybridization (FISH), polymerase chain reaction (PCR) and quantitative real-time PCR (QPCR) were employed to understand the microbial community structure of the granular sludge samples using species specific primers and probes. The results revealed that the dominance of diverse groups of eubacteria belonging to phyla Proteobacteria, Firmicutes and Chloroflexi and an uncultured candidate division WS6 with four different orders of methanogenic Archaea viz., Methanomicrobiales,
Methanococcales, Methanobacteriales and Methanosarcinales belonging to hydrogenotrophic and aceticlastic methanogens were within the reactor samples. Quantification of the 16S rDNA copies of eubacteria and methanogenic Archaea using species-specific primers further confirmed the spatial distribution of these microorganisms within the different compartments of the reactor where, the upper compartments were dominated by eubacteria and the lower compartments by methanogenic Archaea. The concentration of Archaea per nanogram of DNA was much higher (96.28%) than eubacteria (3.78%) in lower compartments, while, the eubacteria concentration increased to 98.34% in upper compartments with a decrease in Archaea quantity (1.66%).
A modified kinetic methane generation model (MMGM) was developed on the basis of mass balance principles with respect to substrate (COD) degradation and the endogenous decay rate to predict CH4 production efficiency of the reactor. Furthermore, a Stover–Kincannon kinetic model was adopted with the aim of predicting the final effluent quality in terms of COD concentration and model coefficients were determined using the data collected from the full–scale reactor. Thereafter, a model-based multi-objective optimization was carried out using the CPMDE algorithm with three–objective functions namely; maximization of volumetric CH4 production rate; minimization of effluent substrate concentration and minimization of biomass washout, in order to increase the overall efficiency of the UASB reactor. Important decision variables and constraints related to the process were set for the optimization. A set of non-dominated solutions with high CH4 production rates of between 2.78 and 5.06 L CH4/g COD/day at low biomass washout concentrations were obtained at almost constant solution for the effluent COD concentration. A high COD removal efficiency (85-87%) at ~30-31˚C and 8-9 h HRT was obtained for the multi-objective optimization problem formulated.
This study could significantly contribute towards optimization of a full–scale UASB reactor treating brewery wastewater for better effluent quality and biogas production. Knowledge on the activity and performance of microbial community present in the granular sludge taken from the full–scale UASB reactor would contribute significantly to future optimization strategies of the reactor. In addition, optimization using an evolutionary algorithm under different operational conditions would help to save both time and resources wasted in operating anaerobic bioreactors.
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