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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.
21

Environmentální bezpečnost systému odpadních vod / Protection of the untreated sewage water environmental

BELEŠOVÁ, Petra January 2015 (has links)
The topic "Environmental Security of Wastewater System" was selected for the creation of my thesis by several fundamental reasons.The main one is the vital importance of water for the functioning of human society.Drinking water sources are limited and the current relatively easy access to good quality water leads to irresponsible waste of this commodity.Besides wasting there is another big problem with environmental pollution,which is closely related to the degradation of sources of drinking water.With the increase of human population,environmental conditions began to worsen rapidly and this issue became to be discussed by multinational organizations.The so-called Environmental Security is currently very topical subject.It is introduced gradually into school curricula.Large amounts of funds have been invested to the environmental safety of water management in the past few years.An especially,there have been build many waste water treatment plants.The thesis is oriented locally on the municipality of Příbram.Its administrative area covers 74 municipalities and military training area of Brdy.The administrative area is mostly formed by smaller communities that are self-sustaining in water management.It is necessary to ensure sufficiently good conditions of the environment to prevent its degradation.The aim of this thesis is mainly to map the impacts of failure of sewage system and eventual propose of appropriate interim solutions of such failure.The research question is closely related to it: What is the current level of environmental safety of water? To achieve the set objectives,primarily I applied the method of literary research,through which was described the basic information necessary to understand the issue.It was also used method of qualitative research,which was carried out on the basis of interviews with experts in that field.The collected data were organized in a logical survey and analyzed by the a SWOT analysis.The thesis is divided into two main sections.The first one is a theoretical part,which describes the water cycle,explains what is infrastructure and,consequently,it highlights the importance of critical infrastructure.It also explains the concept of water management and presents the basic characteristics and methods of processing and treatment of drinking and waste water.It also states the basic legislation governing the issue of water and ultimately defines the concept of environmental security.The second part describes the sewage system in the area of Příbram and maps the ways of creation and the subsequent magnitude of failure of analyzed wastewater treatment plants.In direct relation to this,it assesses the possible emergence of environmental impact.Waste water can be divided into several groups according to where and how they arise.Taking account of their origin,wastewater may contain a wide variety of harmful substances.A failure of the wastewater system would be not only a current problem of environmental pollution at the site where the waste water was getting into the nature,but a long term adverse effect,which would be later manifested in the form of,for example,contamination of soil and groundwater,which would subsequently mix with drinking water resources.It could also lead to the death of some animals,disabling eating crops in that location and spread of various infectious diseases.This condition is highly undesirable and therefore it is necessary to implement preventive measures to prevent environmental safety.From this research,it was found that the formation of potentially serious impacts on the environment due to the failure of the sewage disposal plants in the area of Příbram is not expected.The operators are ready to remove immediately and quite efficiently incurred defects in order to avoid serious long-term failure.In relation to this,the environmental safety of the sewage disposal plants in the area of Příbram can be evaluated as very good.
22

Avaliação da sustentabilidade de sistemas de tratamento de esgotos sanitários : uma proposta metodológica

Sanches, Andréa Bandeira January 2009 (has links)
A sustentabilidade pode ser encarada como uma nova disciplina do conhecimento humano, agregando em seu escopo o conflito entre as dimensões ambiental, econômica e social. Esta Tese desenvolveu uma Metodologia de Avaliação da Sustentabilidade, aplicada a sistemas de tratamento de esgotos, bem como a sua aplicação na forma de um estudo de caso. A referida metodologia insere-se como uma ferramenta que pode ampliar o processo decisório, quando de um Estudo de Concepção, etapa anterior ao desenvolvimento de um projeto de uma estação de tratamento de esgotos, indo além dos critérios técnicos e econômicos. Ainda, dentro de sua estrutura, foi implementada uma plataforma participativa composta pela comunidade em estudo e por especialistas na área de saneamento ambiental. Foram comparadas três alternativas de processos de tratamento passíveis de serem implantadas em uma estação de tratamento de esgotos, situada no município de Capão da Canoa: reator anaeróbio e banhados construídos, lagoas de estabilização e banhados construídos, assim como o sistema de lodos ativados seguidos por uma etapa de desinfecção. Da análise dos referidos processos, a alternativa que contemplou as lagoas de estabilização associadas aos banhados construídos mostrou o melhor desempenho à luz das três dimensões da sustentabilidade. Com base nos resultados obtidos, observou-se que a Metodologia de Avaliação proposta, pode, efetivamente, elucidar os projetistas sobre a questão da sustentabilidade associada aos sistemas de tratamento de esgotos, bem como promover um processo decisório participativo, onde resultem soluções técnicas mais justas e transparentes. / The sustainability can be seen as a new discipline of human knowledge, adding to the scope of the conflict between the environmental, economic and social dimensions. This Thesis developed a methodology for assessment of the sustainability applied to wastewater treatment systems and its application as a case study. The methodology should be seen as a tool that can extend the decison making process, starting from a preliminary study of design, the stage preceding the development of a project from a wastewater treatment plant, going beyond the technical and economical criteria. More, inside its structure was implemented a participatory platform, compound by the community under study and by experts in the field of environmental sanitation. Were compared three alternatives of procedures that can be implanted in a wastewater treatment plant, located in Capão da Canoa: UASB reactor and constructed wetlands, stabilization ponds and constructed wetlands, as well as the activated sludge system followed by a stage of disinfection. From the analyses of those cases, the alternative that included the stabilization ponds associated with constructed wetlands showed the best performance under the perspective of the three dimensions of sustainability. Based on the results, it was observed that the assessment methodology proposed can, indeed, elucidate the designers on the issue of sustainability associated with wastewater treatment systems and promote a participatory decision process with more fair and transparent technical solutions.
23

Avaliação da sustentabilidade de sistemas de tratamento de esgotos sanitários : uma proposta metodológica

Sanches, Andréa Bandeira January 2009 (has links)
A sustentabilidade pode ser encarada como uma nova disciplina do conhecimento humano, agregando em seu escopo o conflito entre as dimensões ambiental, econômica e social. Esta Tese desenvolveu uma Metodologia de Avaliação da Sustentabilidade, aplicada a sistemas de tratamento de esgotos, bem como a sua aplicação na forma de um estudo de caso. A referida metodologia insere-se como uma ferramenta que pode ampliar o processo decisório, quando de um Estudo de Concepção, etapa anterior ao desenvolvimento de um projeto de uma estação de tratamento de esgotos, indo além dos critérios técnicos e econômicos. Ainda, dentro de sua estrutura, foi implementada uma plataforma participativa composta pela comunidade em estudo e por especialistas na área de saneamento ambiental. Foram comparadas três alternativas de processos de tratamento passíveis de serem implantadas em uma estação de tratamento de esgotos, situada no município de Capão da Canoa: reator anaeróbio e banhados construídos, lagoas de estabilização e banhados construídos, assim como o sistema de lodos ativados seguidos por uma etapa de desinfecção. Da análise dos referidos processos, a alternativa que contemplou as lagoas de estabilização associadas aos banhados construídos mostrou o melhor desempenho à luz das três dimensões da sustentabilidade. Com base nos resultados obtidos, observou-se que a Metodologia de Avaliação proposta, pode, efetivamente, elucidar os projetistas sobre a questão da sustentabilidade associada aos sistemas de tratamento de esgotos, bem como promover um processo decisório participativo, onde resultem soluções técnicas mais justas e transparentes. / The sustainability can be seen as a new discipline of human knowledge, adding to the scope of the conflict between the environmental, economic and social dimensions. This Thesis developed a methodology for assessment of the sustainability applied to wastewater treatment systems and its application as a case study. The methodology should be seen as a tool that can extend the decison making process, starting from a preliminary study of design, the stage preceding the development of a project from a wastewater treatment plant, going beyond the technical and economical criteria. More, inside its structure was implemented a participatory platform, compound by the community under study and by experts in the field of environmental sanitation. Were compared three alternatives of procedures that can be implanted in a wastewater treatment plant, located in Capão da Canoa: UASB reactor and constructed wetlands, stabilization ponds and constructed wetlands, as well as the activated sludge system followed by a stage of disinfection. From the analyses of those cases, the alternative that included the stabilization ponds associated with constructed wetlands showed the best performance under the perspective of the three dimensions of sustainability. Based on the results, it was observed that the assessment methodology proposed can, indeed, elucidate the designers on the issue of sustainability associated with wastewater treatment systems and promote a participatory decision process with more fair and transparent technical solutions.
24

Modeling Engineered Nanoparticles Removal by Conventional Activated Sludge Treatment Process in Wastewater Treatment Plant

January 2015 (has links)
abstract: The production and applications of engineered nanomaterials (ENM) has increased rapidly in the last decade, with release of ENM to the environment through the sewer system and municipal wastewater treatment plants (WWTPs) being of concern. Currently, the literature on ENM release from WWTPs and removal of ENM by WWTPs is insufficient and disorganized. There is little quantitative data on the removal of multi-walled carbon nanotubes (MWCNTs), graphene oxide (GO), or few-layer graphene (FLG), from wastewater onto biomass. The removal of pristine and oxidized MWCNTs (O-MWCNTs), graphene oxide (GO), few-layer graphene (FLG) and Tween™ 20-coated Ag ENM by the interaction with biomass were determined by programmable thermal analysis (PTA) and UV-Vis spectrophotometry. The removal of pristine and O-MWCNTs was 96% from the water phase via aggregation and 30-min settling in presence or absence of biomass with an initial MWCNT concentration of 25 mg/L. The removal of 25 mg/L GO was 65% with biomass concentration at or above 1,000 mg TSS/L. The removal of 1 mg/L FLG was 16% with 50 mg TSS/L. The removal of Tween™ 20 Ag ENM with concentration from 0.97 mg/L to 2.6 mg/L was from 11% to 92% with biomass concentration of 500 mg TSS/L to 3,000 mg TSS/L, respectively. A database of ENM removal by biomass was established by analyzing data from published papers, and non-linear solid-liquid distribution functions were built into the database. A conventional activated sludge (CAS) model was built based on a membrane bioreactor (MBR) model from a previous paper. An iterative numeric approach was adapted to the CAS model to calculate the result of non-linear adsorption of ENM by biomass in the CAS process. Kinetic studies of the CAS model showed the model performance changed mostly in the first 10 days after changing influent chemical oxygen demand (COD) concentration, and reached a steady state after 11 days. Over 60% of ENMs which have distribution coefficients in the database reached higher than 50% removal by the CAS model under general operational conditions. This result suggests that traditional WWTP which include the CAS process can remove many known types of ENMs in certain degree. / Dissertation/Thesis / Masters Thesis Civil and Environmental Engineering 2015
25

Avaliação da disposição de lodo gerado numa estação de tratamento de água em reator anaeróbio de fluxo ascendente e manto de lodo UASB. / Evaluation of throwing sludge generated on a treatment water station with an upflow anaerobic sludge blank reactor (UASB).

Carlos Gonzalo Alvarez Rosario 13 March 2007 (has links)
As estações de tratamento de água de abastecimento (ETAs) têm a finalidade de fornecer água potável. Neste processo de tratamento de água são gerados resíduos, os quais historicamente têm sido lançados em cursos de água, aumentando o nível de degradação destes. O presente trabalho teve por objetivo avaliar o impacto do lançamento desses resíduos numa estação de tratamento de esgoto (ETE) com reator anaeróbio de fluxo ascendente e manto de lodo (UASB), buscando estudar uma alternativa para a disposição adequada desses resíduos. Para o estudo da influência do lançamento do lodo da ETA em um reator de fluxo ascendente e manto de lodo (UASB) foram utilizados dois reatores em escala piloto. O esgoto utilizado para alimentar o sistema de tratamento foi proveniente do Conjunto Residencial da Universidade de São Paulo, já o lodo utilizado foi obtido na ETA da cidade de Juquitiba. A presente pesquisa foi dividida em três fases: a primeira etapa (Fase 1) constituiu-se na partida dos reatores UASB 1 e UASB 2; na segunda etapa (Fase 2) estudou-se o desempenho dos sistemas sob regime estabilizado; e na terceira e última etapa (Fase 3) o reator UASB 2 recebeu adição de duas dosagens de lodo de ETA, sendo a primeira de 50 mg/L (Fase 3a) e a segunda de 75 mg/L (Fase 3b), em termos de sólidos em suspensão totais. As condições operacionais adotadas foram: vazão de 50 L/h e tempo de detenção hidráulico (TDH) de 8 horas. Os resultados apresentados no texto indicaram que, com o acréscimo de lodo da ETA, o reator UASB 2 não teve seu desempenho afetado negativamente, e a remoção de matéria orgânica em termos de DQO, DBO e fósforo foi muito próxima entre os reatores UASB 1 e UASB 2. Conclui-se que com a disposição de lodo em um reator UASB, não haverá interferência prejudicial no desempenho operacional do mesmo. / Water treatment stations have the purpose of providing potable water. In this process of water treatment, a variety of residuals are produced; these, historically have been discharged into water streams, increasing the water pollution. The objective of this work was to evaluate the impact of discharging residuals in a treatment station with an Upflow Anaerobic Sludge Blank Reactor (UASB), and try to find an alternative for the appropriate treatment of these. For the study of the influence of discharging WTA sludge into a UASB reactor, two reactors in pilot scale were used. The disposals used to feed the treatment system came from the apartment building where Sao Paulo University students live, while the sludge used was obtained in the water treatment station from Juquitiba city. This research has been divided into three stages: The first one (Stage 1) consisted of the setting of the reactors UASB1 and UASB2. In the second stage (Stage 2) it was studied the performance of the systems in the balance regime. In the third one (Stage 3), the reactor UASB2 received the supply of two portions of WTA sludge, the first one of 50 mg/L (Stage 3a) and the second one of 75 mg/L (Stage 3b). These amounts are determined in terms of the TSS. The operational conditions adopted were flow of 50 L/h and TDH of eight hours. The results obtained indicated that with the addition of WTA sludge the reactor UASB2 did not show inferior performance. At the same time the organic material removal, in terms of DQO, DBO and phosphorous content, was similar between the reactors UASB1 and UASB2, concluding that with the supply of WTP sludge in the reactor UASB, there won\'t he detrimental effects in the reactor performance.
26

Avaliação da sustentabilidade de sistemas de tratamento de esgotos sanitários : uma proposta metodológica

Sanches, Andréa Bandeira January 2009 (has links)
A sustentabilidade pode ser encarada como uma nova disciplina do conhecimento humano, agregando em seu escopo o conflito entre as dimensões ambiental, econômica e social. Esta Tese desenvolveu uma Metodologia de Avaliação da Sustentabilidade, aplicada a sistemas de tratamento de esgotos, bem como a sua aplicação na forma de um estudo de caso. A referida metodologia insere-se como uma ferramenta que pode ampliar o processo decisório, quando de um Estudo de Concepção, etapa anterior ao desenvolvimento de um projeto de uma estação de tratamento de esgotos, indo além dos critérios técnicos e econômicos. Ainda, dentro de sua estrutura, foi implementada uma plataforma participativa composta pela comunidade em estudo e por especialistas na área de saneamento ambiental. Foram comparadas três alternativas de processos de tratamento passíveis de serem implantadas em uma estação de tratamento de esgotos, situada no município de Capão da Canoa: reator anaeróbio e banhados construídos, lagoas de estabilização e banhados construídos, assim como o sistema de lodos ativados seguidos por uma etapa de desinfecção. Da análise dos referidos processos, a alternativa que contemplou as lagoas de estabilização associadas aos banhados construídos mostrou o melhor desempenho à luz das três dimensões da sustentabilidade. Com base nos resultados obtidos, observou-se que a Metodologia de Avaliação proposta, pode, efetivamente, elucidar os projetistas sobre a questão da sustentabilidade associada aos sistemas de tratamento de esgotos, bem como promover um processo decisório participativo, onde resultem soluções técnicas mais justas e transparentes. / The sustainability can be seen as a new discipline of human knowledge, adding to the scope of the conflict between the environmental, economic and social dimensions. This Thesis developed a methodology for assessment of the sustainability applied to wastewater treatment systems and its application as a case study. The methodology should be seen as a tool that can extend the decison making process, starting from a preliminary study of design, the stage preceding the development of a project from a wastewater treatment plant, going beyond the technical and economical criteria. More, inside its structure was implemented a participatory platform, compound by the community under study and by experts in the field of environmental sanitation. Were compared three alternatives of procedures that can be implanted in a wastewater treatment plant, located in Capão da Canoa: UASB reactor and constructed wetlands, stabilization ponds and constructed wetlands, as well as the activated sludge system followed by a stage of disinfection. From the analyses of those cases, the alternative that included the stabilization ponds associated with constructed wetlands showed the best performance under the perspective of the three dimensions of sustainability. Based on the results, it was observed that the assessment methodology proposed can, indeed, elucidate the designers on the issue of sustainability associated with wastewater treatment systems and promote a participatory decision process with more fair and transparent technical solutions.
27

Disposição de resíduos gerados em estações de tratamento de água em estações de tratamento de esgoto / Disposal of water treatment plants sludge in wastewater treatment plants

Paulo Sergio Scalize 08 August 2003 (has links)
O presente trabalho foi realizado em duas fases. Na primeira, foram estimados os efeitos produzidos nos decantadores primários de uma ETE, após receber resíduo da ETA-SC, que utiliza sulfato de alumínio como coagulante. Foram realizados ensaios em colunas de sedimentação, onde os parâmetros SST, SSV, cor, turbidez, DQO, coliformes totais, Escherichia coli e parasitas, pesquisados no sobrenadante, diminuíram com o aumento da quantidade de resíduo adicionado. Com relação aos sedimentos obtidos nas colunas de sedimentação, foi encontrada maior quantidade de ST e menor resistência específica nos lodos provenientes das colunas que receberam os resíduos da ETA-SC. No teste de atividade metanogênica, a concentração molar de metano foi reduzida nos sistemas que receberam resíduo da ETA-SC, influenciando negativamente no desenvolvimento dos microrganismos metanogênicas. As espécies de microrganismos do gênero Methanothrix sp foram inibidas, sendo encontradas em maior número no frasco-reator controle e em menor quantidade a medida que se aumentou a quantidade do resíduo adicionado. Nesta etapa foi constatado que o resíduo da ETA-SC poderá apresentar interferências negativas sobre a digestão anaeróbia do lodo produzido em decantadores primários de uma ETE. Na segunda fase, na estação piloto, composta de lagoa de aeração seguida de lagoa de sedimentação, que recebeu resíduo da ETA-Fonte, que utiliza cloreto férrico como coagulante, foi verificado que tal resíduo melhorou a qualidade do efluente em termos de DQO, DBO, SST, turbidez, cor, amônio, nitrato, NTK e fosfato total. Os parâmetros ST, SDT, cloreto, nitrito, condutividade e pH não apresentaram diferenças significativas. Em relação ao exame microscópico não houve influências negativas no licor misto das lagoas de aeração. O lodo formado nas lagoas de sedimentação piloto apresentou-se em maior quantidade na lagoa que recebeu resíduo da ETA-Fonte. Neste lodo a resistência específica a filtração foi menor em comparação ao lodo da lagoa que não recebeu resíduo da ETA-Fonte. A desidratação deste lodo por centrifugação necessitou menor quantidade de polieletrólito. Baseado neste estudo não foi verificado interferências que possa impedir o lançamento do resíduo da ETA-Fonte na ETE-Araraquara. / This work was carried out in two phases. Effects of disposing the residues from a water treatment plant - ETASC, which uses alum as primary coagulant on the primary settling tanks was evaluated in the first one. Sedimentation tests using column indicated that parameters such as TSS, VSS, colour, turbidity, COD, total coliformes totais, Escherichia coli e parasites in the supernatant decreased with the increase of the amount of the water treatment wastes added to the column. With relation to the sediments produced in the column, it was found great amount of TS and lower specific solids resistance in those generated in the columns where the water treatment plant residues-WTPR were used. Molar concentration of methane was reduced in the tests performed with the sediments produced with water treatment plant residues and thus, altering negatively the development of methanogenic organisms. The growth of species of microorganism of genera Methanothrix sp was inhibited, which were found in great number in the control flask (with out WTPR) and in lower number as it was increased the amount of WTPR added to the column. It was observed that the WTPR generated in the city water treatment plant may interfere in the anaerobic digestion of sludge produced in primary settling tanks of a wastetreatment plant. A continuous pilot plant was operated in the second phase, which consisted of two aerated lagoon each one followed by a settling lagoon. Waste and WTPR from a watter treatment plant which ferric chloride were fed in one of the systems. It was observed that the use of WTPR improved the effluent quality of the settling lagoon evaluated in terms of COD, BOD, TSS, turbidity, color, ammonium, nitrate, TKN and total phosphate. Some parameters, such as TS, TDS, chloride, nitride, conductivity and pH did not present significant differences in both systems. Microscopic examinations indicated that no influence resulted in the aerated lagoon mixed liquor. A higher amount of sludge was formed in the lagoon system which received the WTPR. The specific resistance to filtration of this sludge was lower than that formed in the lagoon system with out WTPR addition. When dewatering both sludges, that one produced with the addition of WTPR required less amount of polymer. It was concluded that the WTPR produced in the water treatment plant of Araraquara may be disposed in the city wastewater treatment plant.
28

Změna kvality vody v malých povodích po postavení čistírny odpadních vod / Water quality change in small watersheds after sewage water treatment plant building

Rödlová, Sylva January 2010 (has links)
Změny kvality vody v malých tocích, vyvolané vybudováním čistírny odpadních vod, představují doposud málo studované a přitom velmi aktuální téma současné hydrologie. Tato studie se zabývá popsáním těchto změn a faktorů, které je ovlivňují. Pro účely výzkumu bylo vybráno pět malých, zemědělsky využívaných povodí prvního řádu (čtyři povodí průměrně 6 km2 , jedno 16 km2 ). V každém zájmovém území byla vždy jedna vesnice od 640 do 2 500 obyvatel. Během 7 - 16 let trvajícího měsíčního monitoringu základních indikátorů kvality vody (O2, BSK5, CHSKCr, TOC, konduktivita, N-NH4, N-NO2, N-NO3, PC, P-PO4) byla zachycena stavba čistíren v obcích. Spolu s daty o účinnosti čistíren byly vyhodnoceny změny kvality vody v toku. Identifikované typy změn ukazují na problematické aspekty vývoje kvality vody v malých povodích. Kromě očekávaného rychlého a razantního snížení hodnot zátěže po výstavbě čistírny odpadních vod se vyskytují i odlišné projevy změn - pouze mírné snížení zátěže, stagnace, dokonce i zvýšení koncentrací sledovaných indikátorů. Mezi další typické změny patří navýšení hodnot 1-2 roky před uvedením čistírny do provozu a opožděná nitrifikace v toku způsobená nevhodným provozem čistírny. Mezi nejdůležitější faktory ovlivňující změny patří provoz čistírny, velikost průtoku recipientu, zemědělské...
29

Devenir de l’arsenic dans une papeterie : étude de cas / Arsenic fate in a pulp and paper mill : a case study

Michon, Clémence 04 February 2011 (has links)
Les objectifs de ce travail étaient de déterminer les sources et le devenir de l’arsenic dans une papeterie vosgienne, et en particulier dans sa station d’épuration, afin de comprendre les variations de la concentration en arsenic dans l’effluent traité par la station et rejeté dans la Moselle.Les papiers récupérés utilisés pour la production de pâte désencrée représentent la source majoritaire d’arsenic pour la papeterie, puis les combustibles incinérés dans le secteur énergie. Les sorties majoritaires sont les cendres produites par le secteur énergie, puis le papier produit. Le devenir de l’arsenic dans le procédé de désencrage est complexe et implique des phénomènes de transfert entre le circuit de la pâte à papier et le circuit des eaux. L’arsenic présent dans les eaux blanches semble provenir des matières en suspension. Des dysfonctionnements dans le secteur énergie ont causé le départ de cendres produites dans la chaudière à la station d’épuration via les eaux de lavage du laveur de fumées. Ces cendres peuvent avoir une concentration en arsenic très importante et pourraient être l’une des causes des dépassements de la limite de rejet en arsenic. La station d’épuration peut éliminer de la phase aqueuse jusqu’à 50 % de l’arsenic entrant à la station après neutralisation/décantation et traitement par boues activées. Un traitement tertiaire par coagulation (par des sels d’aluminium) / floculation / flottation permet de diminuer encore la concentration en arsenic dans le rejet en fonction des conditions de fonctionnement / This study was about the sources and the fate of arsenic in a pulp and paper mill located in the Vosges, and particularly in the wastewater treatment plant, in order to understand the variations of the arsenic concentration in the treated effluent discharged in the Moselle River.The recovered papers used for the production of deinked pulp are the main source of arsenic for the pulp and paper mill, followed by the solid fuels incinerated in the boiler of the energy area of the mill. The main outputs are the ashes produced by the boiler, then the produced paper. The fate of the arsenic in the deinking process is complex and involves transfer phenomena between the pulp and the white water of the process. Arsenic present in white water could come from the suspended solids. Malfunctions in the energy area have caused the departure of ashes to the wastewater treatment plant via the washing water of the flue gas washer. Those ashes may contain a high arsenic concentration and could be one of the sources of the large variations of the arsenic concentration in the effluent of the wastewater treatment plant. This wastewater treatment plant is able to eliminate up to 50% of arsenic of the effluent thanks to neutralization/decantation and biotreatment by activated sludge. A tertiary treatment by coagulation (with aluminum salts) / flocculation / flotation permits to decrease the arsenic concentration in the effluent according to the operating conditions
30

Možnosti a meze vývozu vybraného českého zboží na ruský trh / Possibilities and limits of export of Czech goods to Russian market

Všetičková, Věra January 2014 (has links)
The diploma´s thesis deals with possibilities and limits of export of Czech goods with a specific focus on facilities for wastewater treatment plants in the Russian Federation. In compliance with the theory of internationalization, the first chapter introduces individual forms of entry to foreign markets. Choosing some of the entry modes including export, the thesis mentions specifics of their application on the Russian market. The following chapter outlines current Czech-Russian trade relations which result from valid bilateral, regional and multilateral agreements so as from the crucial political-economic events. In the case study the thesis deals with the very specific opportunities and barriers for the export of Czech facilities for wastewater treatment plants. Therefore, in the particular subchapters the thesis analyzes the current condition of wastewater treatment management in Russia and the legislative and program documents, which stimulate the development and modernization of existing infrastructure. Moreover, the thesis discusses factors that make it difficult to enter the Russian market by Czech companies. Since one of the problems is project financing in Russia, the last chapter deals with the possibilities of financing and insuring export with state support. Overall, the thesis aims to cover the stimuli for export of given goods to Russia, the problems which the exporters might face and their possible solutions as well.

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