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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

Produ??o de ?gua em ETA com altera??o da carreira de filtra??o

Cheng, Man 20 April 2017 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-09-04T21:13:12Z No. of bitstreams: 1 ManChengNg_DISSERT.pdf: 3234152 bytes, checksum: 3dbeca0a3d06fc382d321e61249e422a (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-09-06T23:51:54Z (GMT) No. of bitstreams: 1 ManChengNg_DISSERT.pdf: 3234152 bytes, checksum: 3dbeca0a3d06fc382d321e61249e422a (MD5) / Made available in DSpace on 2017-09-06T23:51:54Z (GMT). No. of bitstreams: 1 ManChengNg_DISSERT.pdf: 3234152 bytes, checksum: 3dbeca0a3d06fc382d321e61249e422a (MD5) Previous issue date: 2017-04-20 / Esta??es de Tratamento de ?gua s?o concebidas em fun??o da qualidade da ?gua do manancial, o que determina diretamente a tecnologia de tratamento a ser utilizada e consequentemente influi nos custos de opera??o e manuten??o. A adequa??o dos processos dentro das ETA ? fundamental para diminui??o dos custos e melhoria na qualidade da ?gua tratada. O processo de filtra??o ? considerado pela literatura como etapa de polimento, respons?vel pela remo??o de part?culas em suspens?o, e remo??o de cistos e oocistos de protozo?rios. A retrolavagem dos filtros pode consumir entre 3% a 10% do volume produzido nas ETA, ou seja, ? relevante no resultado final de produ??o de ?gua. O objetivo geral desse trabalho foi avaliar as modifica??es na produ??o de ?gua na ETA em escala real atrav?s da altera??o nas carreiras de filtra??o. Foram realizadas caracteriza??o f?sica e qu?mica da ?gua de lavagem dos filtros, da ?gua bruta, da ?gua tratada e da ?gua de recircula??o, al?m do monitoramento do n?vel da ?gua dos filtros em carreiras de filtra??o diferentes. Os resultados demonstraram que com o aumento da carreira de filtra??o aumentou a quantidade de s?lidos na ALF; o crescimento do n?vel da ?gua se comporta como fun??o de primeiro grau; pode-se alterar a carreira de filtra??o de 24 horas para 40 horas em condi??es normais na ETA Extremoz. / Water treatment plants are designed according to the water quality on source, which directly sets up the treatment technology to be used and consequently influences costs of operation and maintenance. The adequacy of the processes in WTP is primordial for reducing costs and improving the quality of treated water. The filtration process is considered by the literature as polishing step, responsible for the removal of suspended particles, and removal of protozoan cysts and oocysts. During backwashing it may consume from 3% to 10% of volume produced in the WTP. It?s relevant in the final result of water production. The general objective of this paper was to evaluate modifications in production of water on WTP in real scale through changes in filtration?s careers. Physical and chemical characterization of backwashing?s water of the filters, raw water, treated water and recirculation?s water, as well as the monitoring of the pressure loss of the filters in different filter run. The results showed that: increasing in filter run increased the amount of solids in backwash water; the growth of the loss behaves as a first-degree function; You can change filter run from 24 hours to 40 hours under normal conditions at WTP Extremoz.
2

Influ?ncia da seca extrema na din?mica fitoplanct?nica de um reservat?rio da regi?o tropical semi?rida: uma abordagem morfofuncional

Braga, Gustavo Gir?o 12 May 2015 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-05-10T23:18:28Z No. of bitstreams: 1 GustavoGiraoBraga_DISSERT.pdf: 1165620 bytes, checksum: f556b75a5b1a28aa0fdfdeb9558952d3 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2016-05-18T00:32:20Z (GMT) No. of bitstreams: 1 GustavoGiraoBraga_DISSERT.pdf: 1165620 bytes, checksum: f556b75a5b1a28aa0fdfdeb9558952d3 (MD5) / Made available in DSpace on 2016-05-18T00:32:20Z (GMT). No. of bitstreams: 1 GustavoGiraoBraga_DISSERT.pdf: 1165620 bytes, checksum: f556b75a5b1a28aa0fdfdeb9558952d3 (MD5) Previous issue date: 2015-05-12 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico (CNPq) / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / As secas s?o fen?menos clim?ticos que t?m ocorrido com maior frequ?ncia nas ?ltimas d?cadas e comprometem o fornecimento de ?gua pot?vel em regi?es semi?ridas. A escassez de chuvas aliada ?s altas taxas de evapora??o nessas regi?es causam redu??es significativas nos volumes dos reservat?rios. Essas condi??es, por sua vez, favorecem a concentra??o de nutrientes e o crescimento excessivo da biomassa fitoplanct?nica que inclui flora??es de cianobact?rias potencialmente t?xicas. Portanto, h? uma tend?ncia de que o processo de eutrofiza??o se intensifique nesses reservat?rios de durante per?odos de seca. A comunidade fitoplanct?nica ? capaz de responder rapidamente ?s mudan?as ambientais relacionadas ? disponibilidade de nutrientes e luz, por meio de sua biomassa e composi??o, sendo considerado como um bom preditor das vari?veis ambientais. O objetivo desse estudo foi avaliar a influ?ncia de um per?odo de seca extrema sobre a disponibilidade de luz, nutrientes e sobre a biomassa fitoplanct?nica, utilizando duas abordagens funcionais (Grupos Funcionais de Reynolds e Grupos Morfo-funcionais de Kruk) em um reservat?rio da regi?o semi?rida brasileira. Al?m disso, buscou-se comparar qual das abordagens melhor explicou tais mudan?as ambientais. No presente estudo, foi constatado que a redu??o de 90% do volume do reservat?rio, em conjunto com a redu??o da luminosidade e o aumento da disponibilidade de nutrientes, promove um aumento da biomassa algal. Os resultados das an?lises multivariadas utilizando ambas as abordagens funcionais diferenciaram as amostras dos per?odos de volumes altos e volumes baixos, sendo a luminosidade e os nutrientes as principais vari?veis ambientais que melhor explicaram a associa??o dos grupos funcionais. A comunidade fitoplanct?nica sofreu mudan?as em sua composi??o funcional inicial, caracterizada por organismos t?picos de ambientes meso-eutr?ficos (grupos F e J), para organismos descritores de ambientes eutrofizados e t?rbidos (SN, S1 e III e VII). A abordagem que mais explicou a varia??o dos dados foi a Morfo-Funcional, por?m, apresentou menor sensibilidade em detectar a contribui??o do grupo IV em condi??es de maior luminosidade. A abordagem de grupos funcionais de Reynolds descreveu de maneira mais detalhada a din?mica fitoplanct?nica associada ? redu??o do volume. / Droughts are climatic phenomena whose frequency has increased in the last decades and also compromised drinkable water supplies in semiarid regions. The lack of rain combined with high evaporation rates promotes a significant reduction of the volume of reservoirs in these regions. Shallower conditions favors nutrients concentration and phytoplankton overgrowth, including potentially toxic cyanobacteria blooming. Therefore, there is a tendency to the intensification of eutrophication in those reservoirs during drought periods. Phytoplankton can respond quickly to environmental conditions related to light and nutrient availability by changes in algal biomass and composition, therefore it is considered a good predictor of environmental variables. Two functional approaches - Reynolds?s Functional Groups (FG) and Kruk?s Morphologically Based Functional Groups (MBFG) - were used to assess which environmental variables were responsible for phytoplankton dynamics, in addition to compare which functional approach explains environmental changes better. This study highlights that the reduction of 90% in the volume of a tropical reservoir of Brazilian semi-arid region, as well as light limitation and nutrient increase, can promote phytoplankton overgrowth. Multivariate analyses using both functional approaches indicated a clear separation between high volumes and low volumes conditions, showing that light and nutrient availability were the main variables that better explained the combination of functional groups. The composition of phytoplankton assemblage changed from species of meso-eutrophic habitats (FG: F and J; MBFG: VI), to organisms of eutrophic and turbid environments (FG: SN and M; MBFG: VIII and VII) during shallower conditions. Both ecological approaches described properly the phytoplankton dynamics according to light and trophic state alterations related to the water volume reduction, therefore they can be considered as equivalent approaches for using in similar environments.
3

Impactos do esgotamento h?drico na qualidade da ?gua de um reservat?rio da regi?o semi?rida tropical em evento de seca prolongada

Leite, J?ssica Nayara de Carvalho 22 November 2017 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2018-03-12T14:44:41Z No. of bitstreams: 1 JessicaNayaraDeCarvalhoLeite_DISSERT.pdf: 1653844 bytes, checksum: a1fa3b230b445d2b44c344d47909c125 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2018-03-14T20:07:28Z (GMT) No. of bitstreams: 1 JessicaNayaraDeCarvalhoLeite_DISSERT.pdf: 1653844 bytes, checksum: a1fa3b230b445d2b44c344d47909c125 (MD5) / Made available in DSpace on 2018-03-14T20:07:28Z (GMT). No. of bitstreams: 1 JessicaNayaraDeCarvalhoLeite_DISSERT.pdf: 1653844 bytes, checksum: a1fa3b230b445d2b44c344d47909c125 (MD5) Previous issue date: 2017-11-22 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / Em regi?es mais secas, muitos reservat?rios chegam a volumes t?o baixos que deixam de ser suficientes para abastecimento, sendo assim interrompida a tomada d??gua. No semi?rido brasileiro ? recorrente o esgotamento h?drico em alguns reservat?rios, os quais permanecem secos por meses ou at? anos, o que representa um problema para o abastecimento e causa preju?zos socioecon?micos. Ap?s um evento de esgotamento h?drico, em termos de impactos na qualidade da ?gua, espera-se que haja melhorias ap?s a renova??o com novas ?guas: Menor biomassa algal, maior transpar?ncia da ?gua, menor turbidez e baixa concentra??o de nutrientes. O objetivo deste estudo foi analisar a qualidade da ?gua de um reservat?rio do semi?rido tropical ap?s esgotamento h?drico durante um evento de seca prolongada. O reservat?rio estudado foi Dourado, localizado semi?rido brasileiro. O trabalho foi realizado com tr?s per?odos distintos, determinados de acordo com o volume h?drico. Os per?odos foram marcados por chuvas abaixo da m?dia hist?rica anual, estando assim inseridos em um per?odo de estiagem prolongada. Foram analisadas as vari?veis transpar?ncia da ?gua, turbidez, condutividade el?trica, pH, f?sforo total, f?sforo reativo dissolvido e clorofila-a. Ap?s a renova??o das ?guas, a expressiva redu??o na clorofila-a, indicativa de biomassa algal, indica melhora na qualidade da ?gua em termos de eutrofiza??o, devido ? mudan?a de estado de trofia de eutr?fico para mesotr?fico. As vari?veis pH, condutividade el?trica e turbidez tamb?m sofreram redu??o ap?s a renova??o das ?guas. N?o houve redu??o ap?s o aporte de ?gua para as vari?veis f?sforo total e f?sforo reativo dissolvido em compara??o aos per?odos anteriores. / In dry regions, many reservoirs reach volumes so low that they are no longer sufficient for supply, interrupting the water intake. In the Brazilian semi-arid region, occasional drying is recurrent in some reservoirs, which remains dry for months or even years, representing a problem for the supply and causing socioeconomic issues. After an event of drying, in terms of impacts on water quality, it is expected that there will be improvements after reflooding: Less algal biomass, increased water transparency, decreased turbidity and low concentration of nutrients. The aim of this study was to analyze the water quality of a tropical semi-arid reservoir after drying during an extended drought event. The studied reservoir was Dourado, located in the Brazilian semi-arid. This study consists of the comparison of three distinct periods accordingly to the water volume. Those periods were marked by rainfall below the annual historical average, therefore being inserted in an extended drought period. The variables water transparency, turbidity, electrical conductivity, pH, total phosphorus, soluble reactive phosphorus and chlorophyll-a were analyzed. After the water renewal, a significant reduction in chlorophyll-a, indicative of algal biomass, indicates an improvement in water quality in terms of eutrophication, due to the change of the trophic state from eutrophic to mesotrophic. pH, electrical conductivity and turbidity variables also reduced after the reflooding, indicating an improvement in water quality. There was no reduction in total phosphorus and soluble reactive phosphorus after the reflooding in comparison to the previous periods.
4

O impacto da remo??o de peixes sobre a din?mica e estrutura dos grupos funcionais fitoplanct?nicos em um lago raso tropical durante uma seca severa

Costa, Mariana Rodrigues Amaral da 20 March 2014 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-04-15T23:04:38Z No. of bitstreams: 1 MarianaRodriguesAmaralDaCosta_DISSERT.pdf: 2488995 bytes, checksum: c1bb8bd3c6d969c70744bfd049bfdd73 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2016-04-20T21:52:13Z (GMT) No. of bitstreams: 1 MarianaRodriguesAmaralDaCosta_DISSERT.pdf: 2488995 bytes, checksum: c1bb8bd3c6d969c70744bfd049bfdd73 (MD5) / Made available in DSpace on 2016-04-20T21:52:13Z (GMT). No. of bitstreams: 1 MarianaRodriguesAmaralDaCosta_DISSERT.pdf: 2488995 bytes, checksum: c1bb8bd3c6d969c70744bfd049bfdd73 (MD5) Previous issue date: 2014-03-20 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico (CNPq) / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / A eutrofiza??o artificial ? uma das grandes amea?as ? qualidade ambiental de ecossistemas aqu?ticos em todo o mundo. As expectativas dos cen?rios clim?ticos futuros para regi?es ?ridas e semi?ridas s?o per?odos de secas mais intensas e frequentes, aumentando ainda mais o risco de eutrofiza??o e de flora??es de cianobact?rias. Muitas t?cnicas de restaura??o de lagos eutrofizados foram propostas para reduzir as cargas de nutrientes e melhorar a qualidade da ?gua. Uma t?cnica bastante utilizada ? a biomanipula??o por remo??o de peixes que v?m se mostrando eficiente em lagos eutr?ficos de regi?es temperadas. Trabalha mos a hip?tese de que a remo??o de peixes bent?v oros bioturbadores reduz a biomassa total do fitopl?ncton e altera a composi??o dos grupos funcionais fitoplanct?nicos , refletindo na melhora d a qualidade da ?gua . Assim , este estudo teve como objetivo avaliar o impacto da biomanipula??o na din?mica e estr utura d os grupos funcionais fitoplanct?nicos e n a qualidade da ?gua. Aplicamos a t?cnica da biomanipula??o no lago artificial ESEC, regi?o semi?rida do nordeste brasileiro e analisamos as vari?veis f?sicas e qu?micas da ?gua e a din?mica dos grupos funcion ais fitoplanct?nicos, mensalmente durante o per?odo de novembro de 2012 a agosto de 2013. Com a remo??o dos peixes bioturbadores, observamos um aumento significativo na zona euf?tica, na riqueza de esp?cies fitoplanct?nicas e o recrutamento de grupos funci onais fitoplanct?nicos de algas verdes (grupos F e J) indicadoras de boa qualidade ambiental. Por?m, n?o observamos diferen?as significativas na concentra??o de f?sforo total e na biomassa e diversidade fitoplanct?nica. O efeito da seca severa na regi?o du rante o estudo foi evidente , proporcionando uma redu??o dr?stica no n?vel de ?gua que influenciou na disponibilidade de recursos e afetou a comunidade fitoplanct?nica antes da biomanipula??o . Para avaliar o efeito de uma seca severa sobre a din?mica dos gr upos funcionais fitoplanct?nicos e testar se per?odos de seca s?o favor?veis ? domin?ncia de cianobact?rias, estudamos dois lagos artificiais vizinhos (ESEC e Pocinhos) no semi?rido tropical durante maio de 2012 a fevereiro de 2013. Observamos uma diferenc ia??o temporal das vari?veis abi?ticas e do fitopl?ncton causada pela seca severa. Ambos os lagos apresentaram redu??o de 2 metros do n?vel da ?gua e aumento nos valores de condutividade, turbidez, nas concentra??es de nutrientes e redu??o da transpar?ncia da ?gua, durante o per?odo da seca severa. Por?m, a comunidade fitoplanct?nica respondeu diferente ?s condi??es ambientais dependendo da profundidade de cada lago. O mais profundo (Pocinhos) aumentou a biomassa total do fitopl?ncton e apresentou domin?nci a do grupo funcional de cianobact?rias heterocitadas formadoras de flora??o (grupo S N ) e o lago menos profundo (ESEC) reduziu a biomassa total e apresentou domin?ncia de grupos funcionais de algas flageladas com metabolismo mixotr?fico (grupos W 1 e W 2 ) . Su marizando, o conhecimento sobre os efeitos da biomanipula??o por remo??o de peixes bent?voros bioturbadores em um lago raso no semi?rido tropical ainda ? incipiente e o estudo possui limita??es devido ao evento de seca prolongada durante o per?odo de estud o . Sendo assim, ? necess?rio um monitoramento em longo prazo para investigar os reais efeitos da biomanipula??o no funcionamento do ecossistema. Al?m disso, per?odos de seca podem ter efeitos antag?nicos (aumento ou redu??o) na biomassa total , bem como na composi??o dos grupos funcionais fitoplanct?nicos, que nem sempre levar? ? domin?ncia de cianobact?rias. / The artifi cial eutrophication is one of the biggest t h reat for the quality of aquatic ecosystems in the whole world. The expectations for the future climatic scenarios in arid and semi - arid regions are intense and frequent droughts enhancing the risk of eutrophicati on and cyanobacterial blooms. Restoration techniques of eutrophic lakes were proposed to reduce nutrient loading and improve the water quality. A successful technique used in temperate regions is the biomanipulation by benthivorous fish removal . Our hypoth esis is that the benthivorous fish removal reduces phytoplankton total biomass and change the composition of phytoplankton functional groups, improving water quality. The aim of the study was evaluate the impact of biomanipulation on phytoplankton function al groups and in the water quality. We applied the technique of biomanipulation in the artificial lake ESEC, in a semi - arid region of Brazil and analyzed the physical and chemical variables and the dynamic of phytoplankton functional groups monthly during November 2012 to August 2013. With the removal of benthivorous fish we observed a significant increase of the euphotic depth, phytoplankton richness and the recruitment of green algae (groups F and J ), indicators of good water quality. However, we did not observe significant differences on total phosphorous concentration and on phytoplankton biomass and diversity. The drought effect in the region during the study was evident , promoting a drastic reduction on water level which influenced the availability of resource and affected phytoplankton community before the biomanipulation. To evaluate the effect of severe drought on the dynamic of phytoplankton functional groups and test if the drought periods are favorable to dominance of cyanobacterial groups, we stu died two artificial neighbors lakes (ESEC and Pocinhos) in a semi - arid tropical region during May 2012 to February 2013. We observed a temporal differentiation of biotic and abiotic variables caused by drought. Both lakes presented reduction of 2 meters of water level and increase on conductivity, turbidity, nutrients concentration and a reduction on water transparency, during the severe drought. The deeper lake (Pocinhos) increased phytoplankton total biomass and presented cyanobacterial functional group d ominance (group S N ) and the shallower lake (ESEC) reduced phytoplankton total biomass and presented dominance of mixotrophic and flagellate functional groups (groups W 1 e W 2 ). Summarizing, the knowledge of the effects of benthivorous fish removal in semi - a rid tropical lakes still unknown and this study had limitations caused by the impact of drought. Thus, it is necessary a long term monitoring to investigate the real effects of biomanipulation on the functioning of the studied ecosystems. Otherwise, period s of drought could have opposite effects (increase or reduction) on total biomass and composition of phytoplankton functional groups. Drought not always leads to dominance of cyanobacterial groups.

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