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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

Treatment conditions for the removal of contaminants from road runoff

Hallberg, Magnus January 2007 (has links)
The pollutant load in road runoff is related to traffic densities and road maintenance activities. Inurbanised areas treatment of road runoff is common and often considered necessary. The pollutantsare partitioned between the particulate and dissolved matter. However, the contaminantstend to have an affinity to the particulate material. Sedimentation, the predominant treatmentmethod for road runoff uses various types of ponds. Design tools used for stormwater treatmentsystems are based on extensive data from existing treatment systems. The variations in the empiricaldata make it difficult when attempting to evaluate precise conditions for pollutant removaland thereby minimising the land use for a treatment facility. This is a concern in highly urbanisedareas where land use often is restricted.In this work, field studies were conducted in three separate watersheds along the same motorwaywith an annual average daily traffic exceeding 120,000 vehicles. The aim was to assess treatmentconditions for the removal of contaminants from road runoff.The study of mass transport of total suspended solids used the EU Directive (1991/271/EEC)discharge requirement for urban wastewater treatment: 60 mg/l during winter and summer. Theresults showed that a capture of the total runoff volume was necessary during both seasons. Tenmetals (Al, Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, and Zn), as dissolved and particulate bound, werestudied in the road runoff during a winter season and the following summer period. The dissolvedpart of Al, Cd, Co, Cr, Mn, and Ni was significantly higher in winter. The mass concentration(mg/kg) for all metals was significantly higher over the summer except for Al and Co, whichshowed a higher mass concentration during the winter. The total metal concentration showed agood correlation to total suspended solids (TSS) during winter with exception for Cd. Good correlationto TSS was also found for the summer period for Al, Cu, Fe, Mn, Ni, and Zn. A simplemodel could describe sedimentation by the initial concentration of TSS, albeit road salt (NaCl)had a significant impact on the sedimentation process during winter. Removal of dissolved metalswas studied by column experiments using water granulated blast furnace slag. The result showedgood removal for Cd, Cu, Ni, and Zn independent of NaCl concentrations. Sediment accumulation(mg sediment/mm precipitation) was relatively consistent for the studied summer seasons asopposed to winter. The sediment differed in metal mass concentrations (mg/kg) between theseasons. Concentrations of Cu and Zn were high in regard to the guidelines for sensitivity ofsediment dwelling organisms and Swedish guidelines for contaminated soils.The findings suggest that the entire runoff volume must be captured for treatment. The reductionof TSS concentration could be estimated for a specific surface load (m/h). This would alsoapply for majority of the studied metals that correlated well to the particulate material. Reactivefilter technology using water granulated blast furnace slag could be applied for treatment of runofffor the reduction of dissolved metals. However, long-term studies are necessary for its practicalimplementation. Furthermore; the work shows that on-line turbidity measurements could beused for expedient process control for treatment facilities in similar watersheds dominated byroads. The work could be used together with existing design methods and models to evaluate andoptimise road runoff treatment. / Föroreningsbelastningen i vägdagvatten är beroende av trafikbelastningen och vägunderhållet. Iurbaniserade områden är behandling av dagvatten vanlig och ofta bedömd nödvändig. Föroreningarnaär lösta och partikulära, men har vanligen en affinitet till det partikulära materialet. Denförhärskande behandlingsmetoden för dagvatten är sedimentering, vanligen i dammar. Designmodellernabygger på data från olika befintliga dagvattenanläggningar. Det varierande ursprungettill det empiriska underlaget medför svårighet att precist värdera designförutsättningarna och såledesminimera behandlingsanläggningens storlek. I förtätad stadsmiljö, där tillgång på mark ärbegränsad, kan detta vara ett problem.I detta arbete har fältförsök genomförts i tre avrinningsområden vilka domineras av en motorledmed en årlig dygnstrafik större än 120,000 fordon för att utvärdera behandlingsförutsättningar förvägdagvatten.Masstransporten av suspenderat material (SS) utvärderades utifrån EU Direktivet(1991/271/EEC) och gränsvärdet för avloppsvatten på 60 mg/l under vinter och sommar. Studienvisade att hela avrinningsvolymen bör behandlas oberoende av säsong. Fördelningen mellanpartikulärt och löst material studerades för tio metaller (Al, Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, Zn)under vinter och sommar. Den lösta delen av Al, Cd, Co, Cr, Mn och Ni var signifikant högreunder vintern. Den partikulära koncentrationen (mg/kg) för samtliga metaller var högre undersommaren med undantag för Al och Co vilka förekom i högre halter under vintern. Totalhalten(μg/l) av metallerna korrelerade väl med SS under vintern med undantag för Cd. Likaledes uppvisaderesultaten en god korrelation mellan SS och Al, Cu, Fe, Mn, Ni och Zn under sommaren.Sedimenteringsegenskaperna kunde beskrivas med en enkel modell utifrån koncentration av SS,men förhöjda halter av vägsalt (NaCl) befanns påverka sedimenteringen under vintern. Reduktionav lösta metaller studerades i pilotförsök med vattenkyld granulerad masugnsslagg. God avskiljningerhölls för Cd, Cu, Ni och Zn oberoende av förhöjda halter av vägsalt. Ackumulering avsediment (mg sediment/mm nederbörd) befanns vara konstant under sommaren i motsats tillstuderade vinterperioder. Sedimentkoncentrationerna av Cu och Zn var förhöjda med avseendepå riktlinjer för känslighet hos sedimentlevande organismer samt för återanvändning av slam.Resultaten visar att hela avrinningsvolymen måste behandlas. Reduktion av SS samt huvuddelenav metallerna, vilka visade god korrelation till det partikulära materialet, kan skattas utifrån enspecifik ytbelastning (m/h). Reduktion av lösta metaller kan ske med granulerad masugnsslagg,dock bör långtidsstudier genomföras. Vidare visar studien på möjligheten att nyttja kontinuerligturbiditetsmätning för en effektiv och praktisk processkontroll i reningsanläggningar för liknandeavrinningsområden med hög trafikbelastning. Resultaten av arbetet kan användas för bedömningoch optimering av vägdagvattenbehandling tillsammans med existerande designmetoder och modeller. / QC 20100709
2

Floto-filtração como pós-tratamento de efluente de reator anaeróbio tratando esgoto sanitário / Floto-filtration as post-treatment of an anaerobic reactor effluent

Oliveira, André Luiz de 23 February 2007 (has links)
Este trabalho compreende o estudo do desempenho de sistema piloto de floto-filtração, aplicado ao pós-tratamento de efluente de reator anaeróbio, sob diferentes taxas de aplicação superficial, quantidade de ar fornecida ao processo e leitos filtrantes. O trabalho foi dividido em duas fases: ensaios preliminares (fase 1) e ensaios com o floto-filtro (fase 2), sem utilização de leito filtrante (etapa 1 da fase 2) e com utilização do leito filtrante (etapa 2 da fase 2). A fase 1, realizada com unidade de flotação por ar dissolvido em escala de bancada, apresentou resultados satisfatórios em termos de redução de turbidez, cor e Abs254nm para dosagens de cloreto férrico entre 40 a 80 mg/L na maior parte dos ensaios. Os dados desta fase serviram principalmente para a determinação e adoção dos melhores parâmetros operacionais a serem utilizados na fase seguinte. Na etapa 1 da fase 2, o sistema foi analisado sob a ótica da qualidade da água produzida em condições variáveis de dosagem de cloreto férrico, tempo e gradiente de floculação, taxa de recirculação e taxa de aplicação superficial. Para as amostras coletadas foram analisadas as variáveis turbidez, temperatura, condutividade, DQO, SST, pH, cor, Abs254nm, metais, OD, \'P-PO IND.4\'POT.3-\', NTK e \'N-NH IND.4\'POT.+\'. Foram obtidas eficiências globais de 88 a 97% de redução na turbidez (residual < 20 uT), 84 a 98% de SST (residual < 25 mg/L), 87 a 94% de \'DQO IND.B\' (residual < 60 mg/L), 78 a 92% de \'DQO IND.F\' (residual < 40 mg/L), 85 a 96% de \'P-PO IND.4\'POT.3-\' (residual < 2 mg/L) e menor que 30% para NTK e \'N-NH IND.4\'POT.-\'. Na etapa 2 da fase 2, além das análises supracitadas, foram analisadas as variáveis DBO, coliformes totais e fecais, sulfatos, dureza, alcalinidade, ácidos voláteis e turbidez ao longo do leito filtrante além da medida de perda de carga no decorrer da carreira de filtração. Foram monitorados a perda de carga ao longo do leito filtrante, carreira de filtração. Nesta fase, a instalação piloto de floto-filtração foi avaliada mediante a variação da taxa de aplicação superficial e do leito filtrante. Os resultados foram positivos com efluente final apresentando turbidez média abaixo de 2 uT e duração média da carreira filtração de 24 horas. Foram obtidas eficiências globais de 96 a 99% de redução na turbidez (residual < 7 uT), 96 a 99% de SST (residual < 6 mg/L) , 93 a 96% de \'DQO IND.B\' (residual < 40 mg/L), 89 a 97% de \'DQO IND.F\' (residual < 34 mg/L), 93 a 98% de \'P-PO IND.4\' POT.3-\' (residual < 0,3 mg/L), menor que 30% para NTK e \'N-NH IND.4\' POT.-\', 96 a 98% de cor (residual < 50 uC) e 80 a 82% de Abs254nm (residual < 0,198). Desta forma, em virtude dos bons resultados apresentados, pôde-se constatar que a floto-filtração é uma alternativa atraente no pós-tratamento de efluente de reator anaeróbio. / This works assesses the performance of a floto-filtration pilot system, applied to the post-treatment of an anaerobic reactor effluent, under different superficial application rates, amount of air supplied to the process and filter beds. The work was divided in two phases: preliminary essays (phase 1), essays with the floto-filter without using filter bed (step 1 of phase 2) and essays with the floto-filter using filter beds (step 2 of phase 2). Phase 1, carried out with bench scale dissolved air flotation unit, presented satisfactory results regarding turbidity removal, color and Abs254nm for ferric chloride dosages between 40 - 80 mg/L in most of the essays. The data acquired from this phase were mainly used to determine and adopt the best operational parameters to be employed in the following phase. In step 1 of phase 2, the system was analyzed concerning the quality of the water produced in favorable conditions for ferric chloride dosages, time and flocculation gradient, recirculation gradient and superficial application rate. The following variables were analyzed from the collected samples: turbidity, temperature, conductivity, COD, TSS, pH, color, Abs254nm, metais, OD, \'P-PO IND.4\'POT.3-\', NTK and \'N-NH IND.4\'POT.+\'. Global efficiencies of 88 to 97% for turbidity removal (residual < 20 uT), 84 to 98% for TSS (residual 25 mg/L), 87 to 94% for COD (residual < 60 mg/L), 78 to 92% for CODF (residual < 40 mg/L), 85 to 96% \'P-PO IND.4\'POT.3-\' (residual < 2 mg/L) and less than 30% for NTK and \'N-NH IND.4\'POT.+\' were obtained. In step 2 of phase 2, besides the aforementioned analyses, BOD, total and fecal coliforms, sulphates, hardness, alkalinity, volatile acids and turbidity throughout the filter in addition to the measure of headloss during the filter run. In this phase, the floto-filtration pilot plant was assessed varying the superficial application and filter bed rate. The results were positive with the final effluent presenting mean turbidity below 2 uT and mean filter run time of 24 hours. Global efficiencies of 96 to 99% for turbidity removal (residual < 7 uT), 96 to 99% for TSS (residual < 6 mg/L), 93 to 96% for \'COD IND.B\' (residual < 40 mg/L), 89 to 97% for \'COD IND.F\' (residual < 34 mg/L), 93 to 98% for \'P-PO IND.4\'POT.3-\' (residual < 0,3 mg/L), less than 30% for NTK and \'N-NH IND.4\'POT.-\', 96 to 98% for color (residual < 50 uC) and 80 to 82% for Abs254nm (resisual < 0,198). Thus, due to the good results that were presented, it can be said that floto-filtration is an attractive alternative for the post-treatment of an anaerobic reactor effluent.
3

Floto-filtração como pós-tratamento de efluente de reator anaeróbio tratando esgoto sanitário / Floto-filtration as post-treatment of an anaerobic reactor effluent

André Luiz de Oliveira 23 February 2007 (has links)
Este trabalho compreende o estudo do desempenho de sistema piloto de floto-filtração, aplicado ao pós-tratamento de efluente de reator anaeróbio, sob diferentes taxas de aplicação superficial, quantidade de ar fornecida ao processo e leitos filtrantes. O trabalho foi dividido em duas fases: ensaios preliminares (fase 1) e ensaios com o floto-filtro (fase 2), sem utilização de leito filtrante (etapa 1 da fase 2) e com utilização do leito filtrante (etapa 2 da fase 2). A fase 1, realizada com unidade de flotação por ar dissolvido em escala de bancada, apresentou resultados satisfatórios em termos de redução de turbidez, cor e Abs254nm para dosagens de cloreto férrico entre 40 a 80 mg/L na maior parte dos ensaios. Os dados desta fase serviram principalmente para a determinação e adoção dos melhores parâmetros operacionais a serem utilizados na fase seguinte. Na etapa 1 da fase 2, o sistema foi analisado sob a ótica da qualidade da água produzida em condições variáveis de dosagem de cloreto férrico, tempo e gradiente de floculação, taxa de recirculação e taxa de aplicação superficial. Para as amostras coletadas foram analisadas as variáveis turbidez, temperatura, condutividade, DQO, SST, pH, cor, Abs254nm, metais, OD, \'P-PO IND.4\'POT.3-\', NTK e \'N-NH IND.4\'POT.+\'. Foram obtidas eficiências globais de 88 a 97% de redução na turbidez (residual < 20 uT), 84 a 98% de SST (residual < 25 mg/L), 87 a 94% de \'DQO IND.B\' (residual < 60 mg/L), 78 a 92% de \'DQO IND.F\' (residual < 40 mg/L), 85 a 96% de \'P-PO IND.4\'POT.3-\' (residual < 2 mg/L) e menor que 30% para NTK e \'N-NH IND.4\'POT.-\'. Na etapa 2 da fase 2, além das análises supracitadas, foram analisadas as variáveis DBO, coliformes totais e fecais, sulfatos, dureza, alcalinidade, ácidos voláteis e turbidez ao longo do leito filtrante além da medida de perda de carga no decorrer da carreira de filtração. Foram monitorados a perda de carga ao longo do leito filtrante, carreira de filtração. Nesta fase, a instalação piloto de floto-filtração foi avaliada mediante a variação da taxa de aplicação superficial e do leito filtrante. Os resultados foram positivos com efluente final apresentando turbidez média abaixo de 2 uT e duração média da carreira filtração de 24 horas. Foram obtidas eficiências globais de 96 a 99% de redução na turbidez (residual < 7 uT), 96 a 99% de SST (residual < 6 mg/L) , 93 a 96% de \'DQO IND.B\' (residual < 40 mg/L), 89 a 97% de \'DQO IND.F\' (residual < 34 mg/L), 93 a 98% de \'P-PO IND.4\' POT.3-\' (residual < 0,3 mg/L), menor que 30% para NTK e \'N-NH IND.4\' POT.-\', 96 a 98% de cor (residual < 50 uC) e 80 a 82% de Abs254nm (residual < 0,198). Desta forma, em virtude dos bons resultados apresentados, pôde-se constatar que a floto-filtração é uma alternativa atraente no pós-tratamento de efluente de reator anaeróbio. / This works assesses the performance of a floto-filtration pilot system, applied to the post-treatment of an anaerobic reactor effluent, under different superficial application rates, amount of air supplied to the process and filter beds. The work was divided in two phases: preliminary essays (phase 1), essays with the floto-filter without using filter bed (step 1 of phase 2) and essays with the floto-filter using filter beds (step 2 of phase 2). Phase 1, carried out with bench scale dissolved air flotation unit, presented satisfactory results regarding turbidity removal, color and Abs254nm for ferric chloride dosages between 40 - 80 mg/L in most of the essays. The data acquired from this phase were mainly used to determine and adopt the best operational parameters to be employed in the following phase. In step 1 of phase 2, the system was analyzed concerning the quality of the water produced in favorable conditions for ferric chloride dosages, time and flocculation gradient, recirculation gradient and superficial application rate. The following variables were analyzed from the collected samples: turbidity, temperature, conductivity, COD, TSS, pH, color, Abs254nm, metais, OD, \'P-PO IND.4\'POT.3-\', NTK and \'N-NH IND.4\'POT.+\'. Global efficiencies of 88 to 97% for turbidity removal (residual < 20 uT), 84 to 98% for TSS (residual 25 mg/L), 87 to 94% for COD (residual < 60 mg/L), 78 to 92% for CODF (residual < 40 mg/L), 85 to 96% \'P-PO IND.4\'POT.3-\' (residual < 2 mg/L) and less than 30% for NTK and \'N-NH IND.4\'POT.+\' were obtained. In step 2 of phase 2, besides the aforementioned analyses, BOD, total and fecal coliforms, sulphates, hardness, alkalinity, volatile acids and turbidity throughout the filter in addition to the measure of headloss during the filter run. In this phase, the floto-filtration pilot plant was assessed varying the superficial application and filter bed rate. The results were positive with the final effluent presenting mean turbidity below 2 uT and mean filter run time of 24 hours. Global efficiencies of 96 to 99% for turbidity removal (residual < 7 uT), 96 to 99% for TSS (residual < 6 mg/L), 93 to 96% for \'COD IND.B\' (residual < 40 mg/L), 89 to 97% for \'COD IND.F\' (residual < 34 mg/L), 93 to 98% for \'P-PO IND.4\'POT.3-\' (residual < 0,3 mg/L), less than 30% for NTK and \'N-NH IND.4\'POT.-\', 96 to 98% for color (residual < 50 uC) and 80 to 82% for Abs254nm (resisual < 0,198). Thus, due to the good results that were presented, it can be said that floto-filtration is an attractive alternative for the post-treatment of an anaerobic reactor effluent.
4

Projekt přírodní čistírny odpadních vod pro obec Hvozd / Project of a natural wastewater treatment plant for the municipality of Hvozd

Šenková, Lucie January 2022 (has links)
The topic to Diploma Thesis is design of Biological Wastewater Treatment for 450 PE in Hvozd Commune (Region Olomoucký). First part is dedicated to description of multiple possible variants of design. In the following part is more detailed described chosen technology. Except from description of technology are also shown parameters calculations proposal. Some of the main reasons for preference of Biological Wastewater Treatment are low maintenance requirements, independence of energy supply or possibility of future sludge treatment. Foundational materials for the design were first, Local Zoning Plan which describes current and future drainage and wastewater disposal situation. Second, study aims at parameters calculations of French system. Project documentation is part and parcel of this thesis. Documentation will also be a basis for planning building permission.

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