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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.
71

Tratamento de efluente de piscicultura orgânica utilizando macrófitas aquáticas Eichhornia crassipes (mart. Solms) e Egeria densa (Planchon.) / Treatment of effluent of organic pisciculture using macrophytes aquatics eichhornia crassipes (mart. solms) e egeria densa (planchon.)

Gentelini, André Luis 15 February 2007 (has links)
Made available in DSpace on 2017-05-12T14:46:53Z (GMT). No. of bitstreams: 1 Andre Luis Gentelini.pdf: 1181211 bytes, checksum: 52d87460c18b71f3e2128d705863b662 (MD5) Previous issue date: 2007-02-15 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The objective of the recent research was to evaluate the efficiency of a system of aquatic treatment being used macrophytes Eichhornia crassipes (water hyacinth) and Egeria dense (egeria) in three times of hydraulic detention, the removal of pollutants of the effluent one of organic culture of tilápias of the Nile (Oreochromis niloticus), and to get given of production of biomass of the aquatics macrophytes. The work was carried through in the Paturi farm, Terra Roxa city, state of the Paraná, during the period of 6 weeks. The system was composed for 18 experimental tanks of 2.00 x 1.00 x 0.65m length, width and depth respectively, coated with polypropylene canvas. An entirely randomized 2 macrophytes x 3 hydraulic detention times (HDT) and 3 repetitions. The used HDT had been of 04h, outflow of &#8776; 4.15 L.min-1, 08h, outflow of &#8776; 2.10 L.min-1 and 12h, outflow of &#8776; 1.40 L.min-1. The samples were collected in inlet and outlet of the system, in intervals of five days, being evaluated total nitrogen (NT), total phosphorus (PT), ammonia, nitrite, nitrate, turbidity, DQO, pH and electric conductivity. The temperature was measures daily. The biomass production was evaluated to the end of the experiment. For NT in such a way the water hyacinth and would egeria as it biggest removal (P<0.05) 39.90% and 37.38%, respectively was observed in the HDT of 12 hours, not differing from the HDT of 8 hours. The best removals of PT (P<0.05) 41.57% and 43.42% had been observed in the HDT of 12 hours for the water hyacinth and would egeria respectively. In the case of the turbidez, biggest removal 62.74% (P<0.05) was observed in the HDT of 12 hours for the water hyacinth, not differing from the HDT of 8 hours, already for it would egeria optimum resulted (P<0.05) was observed in the HDT of 12 hours with 81.81%. For the DQO, as much the water hyacinth as it would egeria it, the best ones resulted of removal (P<0.05) 63.61% and 62.64% had been observed in the HDT of 12 not differing from the HDT of 8 hours. For the biomass production the water hyacinth presented the best ones resulted, being greater 8.95 kg.m-2 for the HDT of 4 hours, followed for the HDT of 12 and 8 hours, already for would egeria optimum 0.05kg.m-2 in the HDT of 12 hours result, followed for the HDT of 8 and 4 hours. One concludes that for removal of NT, PT, turbidez and DQO the TDH of 12 hours was what it presented better resulted for both the macrophytes. The water hyacinth produced more biomass that egeria in these conditions in all the TDH. / O presente trabalho teve por objetivo avaliar a eficiência de um sistema de tratamento utilizando macrófitas aquáticas Eichhornia crassipes (aguapé) e Egeria densa (egeria) em três tempos de detenção hidráulica, na remoção de poluentes do efluente de cultivo orgânico de tilápias do Nilo (Oreochromis niloticus) e obter dados sobre a produção de biomassa das macrófitas aquáticas. O trabalho foi realizado na fazenda Paturi, município de Terra Roxa, estado do Paraná, durante o período de 6 semanas. O sistema foi composto por 18 tanques experimentais de 2,00 x 1,00 x 0,65 m de comprimento, largura e profundidade, respectivamente, revestidos com lona de polipropileno. O delineamento foi inteiramente casualizado, 2 macrófitas x 3 tempos de detenção hidráulica (TDH) e 3 repetições. Os TDH utilizados foram de 4 h, vazão de &#8776; 4,15 L.min-1, 8 h, vazão de &#8776; 2,10 L.min-1 e 12 h, vazão de &#8776; 1,40 L.min-1. As amostras foram coletadas na entrada e saída do sistema, em intervalos de cinco dias, avaliando-se o nitrogênio total (NT), fósforo total (PT), amônia, nitrito, nitrato, turbidez, DQO, pH e condutividade elétrica. A temperatura foi medida diariamente. A produção de biomassa foi avaliada ao final do experimento. Para NT, tanto para o aguapé como para a egeria, a maior remoção (P<0,05) foi de 39,90% e 37,38%, respectivamente, observada no TDH de 12 horas, não diferindo do TDH de 8 horas. As melhores remoções de PT (P<0,05) 41,57% e 43,42% foram observadas no TDH de 12 horas para o aguapé e egeria, respectivamente. No caso da turbidez, a maior remoção 62,74% (P<0,05) foi observada no TDH de 12 horas para o aguapé, não diferindo do TDH de 8 horas. Para a egeria o melhor resultado (P<0,05) foi observado no TDH de 12 horas com 81,81%. Para a DQO, tanto o aguapé como a egeria, os melhores resultados de remoção (P<0,05) 63,61% e 62,64% foram observados no TDH de 12 horas, não diferindo do TDH de 8 horas. Para a produção de biomassa o aguapé apresentou os melhores resultados, sendo o maior 8,95 kg.m-2 para o TDH de 4 horas, seguido pelo TDH de 12 e 8 horas. Para a egeria o melhor resultado 0,05 kg.m-2 no TDH de 12 horas, seguido pelos TDH de 8 e 4 horas. Conclui-se que. para remoção de NT, PT, turbidez e DQO, o TDH de 12 horas foi o que apresentou melhor resultado para ambas as macrófitas. O aguapé produziu mais biomassa que a egeria nessas condições em todos os TDH.
72

Uso de aguapé (Eichhornia crassipes) em sistema de tratamento de efluente de matadouro e frigorífico e avaliação de sua compostagem

Mees, Juliana Bortoli Rodrigues 27 March 2006 (has links)
Made available in DSpace on 2017-05-12T14:48:07Z (GMT). No. of bitstreams: 1 Juliana Bortoli Rodrigues Mees.pdf: 2709034 bytes, checksum: 02264027f5193bac921eb872df0081a9 (MD5) Previous issue date: 2006-03-27 / The objective of the recent research was to evaluate the water hyacinth performance (E. crassipes), applied in situ in a slaughter house treatment system, located in the west of the Paraná state, observing the nutrients removal (nitrogen composts and total phosphorus), organic matter (COD and BOD), turbidity and suspended solids, obtaining as well data from the production, management and composting practices of the biomass generated in the system. The plants were introduced into the forth tank of the industry stabilization lagoons system, covering 35m2 of the total area delimitated for the experiment: 870m2. During a period of 11 months (47 weeks) of water hyacinth development, physic and chemical parameters were monitored monthly and meteorological parameters were monitored daily or weekly. In order to search information about the degradation of the water hyacinths removed from the treatment, another experiment was conduced in plant pilot. Eight composting piles were built measuring approximately 0.60m3, with four distinct treatments that were done twice. The treatments were T1 - Water hyacinth (E. crassipes), T2 - Water hyacinth and swine excrement (7:1), T3 - Water hyacinth, swine excrement and earth (7:1:0,67), T4 - Water hyacinth, swine excrement and cellulosic gut (7:1:0,67), for a period of 90 days. The temperature was monitored daily, and humidity, cinder, nitrogen and total organic carbon were monitored monthly. The result obtained, during 11 months, were promising and the efficient averages of 26.3% of COD and 32.5% of BOD removal were observed, with a maximum removal of 77.2% of COD and 77.87% of BOD. About the nutrient removal, a 21.2% average of nitrogen removal was observed, with a maximum removal of 87.9%, an 11.0% average for ammoniac nitrogen, with maximum of 47.5%, and an 11.1% average and maximum of 38.9% for total phosphorus, during an average of 5 days of retention. An increase in the water turbidity was noticed during the months of high pluviometric precipitation; however, the efficiency of the process was positive during all the monitoring period, with a maximum removal of 58.1%. Considering the C/N relation as a compost maturity indicator, the T4 treatment (water hyacinth, swine excrement and cellulosic gut) had the shorter period of stabilization: 60 days. / O presente trabalho teve por objetivo avaliar o desempenho da macrófita aquática (Eichhornia crassipes), aplicada in situ em sistema de tratamento de um matadouro e frigorífico, localizado no Oeste do Estado do Paraná, com relação à remoção de nutrientes (formas de nitrogênio e fósforo total), matéria orgânica (DBO e DQO), turbidez e sólidos sedimentáveis, bem como obter dados da produção, de práticas de manejo e compostagem da biomassa gerada no sistema. As plantas foram introduzidas na quarta célula do sistema de lagoas de estabilização da indústria, ocupando 35m2 da área total delimitada para o experimento: 870m2. Durante o período de 11 meses (47 semanas) de desenvolvimento das macrófitas na lagoa, realizou-se o monitoramento de parâmetros físico-químicos, analisados com freqüência mensal e parâmetros meteorológicos, coletados com freqüência diária e/ou semanal. Com intuito de buscar informações sobre a degradação das macrófitas retiradas do sistema de tratamento, foi conduzido um experimento em planta piloto, montando-se oito leiras de compostagem com aproximadamente 0,60m3, com quatro tratamentos distintos, sendo: T1 - Aguapé (E. crassipes), T2 - Aguapé e dejeto suíno (7:1), T3 - Aguapé, dejeto suíno e terra (7:1:0,67), T4 - Aguapé, dejeto suíno e tripa celulósica (7:1:0,67), por um período de 90 dias, monitorando-se semanalmente a temperatura, e mensalmente a umidade, cinzas, nitrogênio e carbono orgânico total. Os resultados obtidos, durante os 11 meses do experimento, foram promissores e observou-se uma eficiência media de remoção de DQO de 26,3% e de DBO de 32,5%, com remoção máxima de DQO de 77,2% e de DBO de 77,8%. Em relação aos nutrientes, observou-se uma remoção média de nitrogênio total de 21,2% com máxima de 87,9%, de nitrogênio amoniacal de 11,0% com máxima de 47,5% e de fósforo total de 11,1% com máxima de 38,9%, para um tempo médio de retenção de cinco dias. Com relação à turbidez, observou-se aumento da turbidez afluente nos meses com maior índice de precipitação pluviométrica, contudo a eficiência manteve-se positiva durante todo período de monitoramento, com remoção máxima de 58,1%. Considerando a relação C/N como um indicador da maturidade do composto, observou-se que o tratamento T4 (aguapé, dejeto e tripa celulósica) obteve o menor período de estabilização do composto orgânico: 60 dias.
73

Optimization of BNR from wastewater using SBR and A²O processes

Guo, Lei January 2011 (has links)
University of Macau / Faculty of Science and Technology / Department of Civil and Environmental Engineering
74

Efterpolering med våtmark : Hur kan det användas vid Haga reningsverk?

Carlsen, Inger-Marie January 2015 (has links)
The aim of this report is to present a proposal for a constructed wetland as a complement toHaga treatment plants, Surahammar. First, a literature study in the subject was made andthen a case study was conducted, where Ekeby and Trosa wetland was visited. Parallel anarchival study was performed and several field visits were made to the proposed site toinvestigate the local conditions for constructing a wetland adjacent to Haga treatment plants.Finally, a proposal for the design of the constructed wetland was made. The proposalincludes an oxygenating area for reduction of ammonium to nitrate followed by a system ofdams and channels to convert nitrate to nitrogen diffuses into the air. Phosphorus removaltakes place throughout the residence time in the wetland, as well as reduction of the bacterialload. Expected results for the outgoing water from the wetland is that P-tot can be reduced to0.10-0.11 mg / l, N-tot can be reduced to 11-14 mg / l, a reduction of E. coli, fecal streptococciand intestinal streptococci by 70-99% and a little reduction of residues from drugs take placedue to oxygenation and the UV-irradiation of the water. / Allt vatten här på jorden ingår i den hydrologiska cykeln, så även det renade avloppsvattnet.Avloppsvatten innehåller bland annat kväve och fosfor vilka bidrar till övergödningen avsjöar, vattendrag och hav. Övergödningen är ett utbrett problem och i Västmanland är 53 %av länets sjöar och vattendrag utsatta för det.Syftet med den här rapporten är att ta fram ett förslag till våtmark för Haga reningsverk,Surahammar. Först har information om hur en våtmark kan användas för efterpolering avrenat avloppsvatten tagits fram för att därefter nyttjas som grund i ett förslag till våtmark förHaga reningsverk, Surahammar. Först gjordes en litteraturstudie inom ämnesområdet ochdärefter gjordes en fallstudie där Ekeby och Trosa våtmark besöktes. Parallellt utfördes enarkivstudie och flera områdesbesök på den tilltänkta platsen för att få fram vilkaförutsättningar som finns för att anlägga en våtmark i anslutning till Haga reningsverk ochsist gjordes ett förslag på en våtmark.Anledningen till att anlägga en våtmark kan vara flera, men att avskilja fosfor, kväve samtbryta ner organiskt material är vanliga orsaker. En våtmark fungerar som ett kompletterandesteg till det ordinarie reningsverket och minskar belastningen på recipienten. Hur mycketutsläppen reduceras beror på många faktorer och egenskaper där utformning, vattnetsuppehållstid, syresättning och tillgång till organiskt material är viktiga men även parametrarsom förbehandling av avloppsvattnet och belastningen på våtmarken spelar stor roll. Ävenväxtligheten i våtmarken påverkar det slutliga resultatet, både vad det gäller vad och hurmycket som avskiljs. Avskiljningen av fosfor och kväve sker främst genom sedimentation ochnäringsupptag till växter samt att kväve även avskiljs vid denitrifikation. För den långsiktigaavskiljningen av kväve från vattnets kretslopp är nitrifikation och denitrifikation de som harstörst betydelse. Nitrifikationsprocessen är när ammoniumjoner omvandlas till nitratjoneroch det kräver god tillgång på syre, därefter följer denitrifikationen när nitratjonerna undersyrefria förhållanden omvandlas till kvävgas som diffunderar upp i atmosfären. För attnitrifikationsprocessen ska kunna fungera krävs antingen att det finns ennitrifikationsanläggning i reningsverket eller en syresättningsfas i våtmarken. Det kan skapasgenom att börja våtmarken med en översilningsäng, där det renade avloppsvattnet får strilaner över en bevuxen äng. Vattnet syresätts av luften och nitrifikationsbakterier som trivs bra iväxtligheten utför nitrifikationsprocessen och omvandlar ammoniumjonerna till nitratjoner.Därefter följer ett system av dammar och kanaler där denitrifikationsprocessen tar vid ochomvandlar nitratjonerna till harmlöst kväve. Även i dammar och kanaler har växtlighetenstor betydelse eftersom det bildas biofilm, ett tunt lager av bakterier på växterna, som deltar iden biologiska processen av nedbrytning av organiskt material samt avskiljning av fosfor ochkväve i vattnet.När vattnet passerar genom våtmarken sker också en reducering av antalet bakterier somfinns i det renade avloppsvattnet. Mätningar av E. coli, fekala streptokocker, Koliformabakterier och intestinala enterokocker visar på att halterna kan reduceras kraftigt. Även vissaläkemedel visar tendenser till att brytas ned, men läkemedel är en komplex grupp och detfinns begränsad kunskap om deras omvandling och påverkan i miljön. Det finns dock indikationer om att nedbrytningen av läkemedelsrester är högre i de våtmarker som harsyresättande delar som till exempel översilningsäng.Haga reningsverk är beläget strax utanför Surahammars tätort och har idag en kulvert somleder ut det renade avloppsvattnet från verket till recipienten. Mellan Haga och recipientenligger ett markområde på cirka 750 gånger 750 meter som skulle kunna utnyttjas till envåtmark. Redan idag ligger utsläppsvärdena för Haga reningsverk under de tillåtna halternamen en önskan att ytterligare minska belastningen på miljön finns. Vid analysering avutsläppsvärden för Haga reningsverk framkom att ammoniumkväve utgör en stor andel avutgående totalkväve samt att halterna av totalfosfor, BOD7 och suspenderade ämnen är lågatill måttliga. Ett förslag på våtmark anpassat till de förutsättningar som råder vid Hagareningsverk har tagits fram och presenteras i rapporten. Våtmarken föreslås innehålla tvåsektioner med först en översilningsäng för att reducera den höga andelen ammoniumkväveoch därefter ett damm och kanalsystem för att reducera nitratkvävet. Under hela processensker avskiljning av fosfor samt reducering av bakterier och en viss nedbrytning avläkemedelsrester. Förväntade resultat för det utgående vattnet från våtmarken är att P-totkan reduceras till 0,10–0,11 mg/l, N-tot kan reduceras till 11–14 mg/l, en reducering av E.coli, fekala streptokocker och intestinala streptokocker med 70-99 % samt att en vissminskning sker av läkemedelsrester tack vare syresättning och solens UV-bestrålning avvattnet.
75

Formation of denitrification intermediates and their impact on process performance

Mr Scott McMurray Unknown Date (has links)
No description available.
76

Formation of denitrification intermediates and their impact on process performance

Mr Scott McMurray Unknown Date (has links)
No description available.
77

Formation of denitrification intermediates and their impact on process performance

Mr Scott McMurray Unknown Date (has links)
No description available.
78

Microalgal Biofilms for Treatment of Domestic Wastewater and Resource Recovery

January 2016 (has links)
abstract: The application of microalgal biofilms in wastewater treatment has great advantages such as abolishing the need for energy intensive aerators and recovering nutrients as energy, thus reducing the energy requirement of wastewater treatment several-fold. A 162 cm2 algal biofilm reactor with good wastewater treatment performance and a regular harvesting procedure was studied at lab scale to gain an understanding of effectual parameters such as hydraulic retention time (HRT; 2.6 and 1.3 hrs), liquid level (LL; 0.5 and 1.0 cm), and solids retention time (SRT; 3 and 1.5 wks). A revised synthetic wastewater “Syntho 3.7” was used as a surrogate of domestic primary effluent for nutrient concentration consistency in the feed lines. In the base case (2.6 hr HRT, 0.5 cm LL, and 3 wk SRT), percent removals of 69 ± 2 for total nitrogen (TN), 54 ± 21 for total phosphorous (TP), and 60 ± 7 for chemical oxygen demand (COD) were achieved and 4.0 ± 1.6 g/m2/d dry biomass was produced. A diffusion limitation was encountered when increasing the liquid level, while the potential to further decrease the HRT remains. Nonlinear growth kinetics was observed in comparing SRT variations, and promoting autotrophic growth seems possible. Future work will look towards producing a mathematical model and further testing the aptness of this system for large-scale implementation. / Dissertation/Thesis / Masters Thesis Chemical Engineering 2016
79

Tratamento de efluente de piscicultura orgânica utilizando macrófitas aquáticas Eichhornia crassipes (mart. Solms) e Egeria densa (Planchon.) / Treatment of effluent of organic pisciculture using macrophytes aquatics eichhornia crassipes (mart. solms) e egeria densa (planchon.)

Gentelini, André Luis 15 February 2007 (has links)
Made available in DSpace on 2017-07-10T19:23:41Z (GMT). No. of bitstreams: 1 Andre Luis Gentelini.pdf: 1181211 bytes, checksum: 52d87460c18b71f3e2128d705863b662 (MD5) Previous issue date: 2007-02-15 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The objective of the recent research was to evaluate the efficiency of a system of aquatic treatment being used macrophytes Eichhornia crassipes (water hyacinth) and Egeria dense (egeria) in three times of hydraulic detention, the removal of pollutants of the effluent one of organic culture of tilápias of the Nile (Oreochromis niloticus), and to get given of production of biomass of the aquatics macrophytes. The work was carried through in the Paturi farm, Terra Roxa city, state of the Paraná, during the period of 6 weeks. The system was composed for 18 experimental tanks of 2.00 x 1.00 x 0.65m length, width and depth respectively, coated with polypropylene canvas. An entirely randomized 2 macrophytes x 3 hydraulic detention times (HDT) and 3 repetitions. The used HDT had been of 04h, outflow of &#8776; 4.15 L.min-1, 08h, outflow of &#8776; 2.10 L.min-1 and 12h, outflow of &#8776; 1.40 L.min-1. The samples were collected in inlet and outlet of the system, in intervals of five days, being evaluated total nitrogen (NT), total phosphorus (PT), ammonia, nitrite, nitrate, turbidity, DQO, pH and electric conductivity. The temperature was measures daily. The biomass production was evaluated to the end of the experiment. For NT in such a way the water hyacinth and would egeria as it biggest removal (P<0.05) 39.90% and 37.38%, respectively was observed in the HDT of 12 hours, not differing from the HDT of 8 hours. The best removals of PT (P<0.05) 41.57% and 43.42% had been observed in the HDT of 12 hours for the water hyacinth and would egeria respectively. In the case of the turbidez, biggest removal 62.74% (P<0.05) was observed in the HDT of 12 hours for the water hyacinth, not differing from the HDT of 8 hours, already for it would egeria optimum resulted (P<0.05) was observed in the HDT of 12 hours with 81.81%. For the DQO, as much the water hyacinth as it would egeria it, the best ones resulted of removal (P<0.05) 63.61% and 62.64% had been observed in the HDT of 12 not differing from the HDT of 8 hours. For the biomass production the water hyacinth presented the best ones resulted, being greater 8.95 kg.m-2 for the HDT of 4 hours, followed for the HDT of 12 and 8 hours, already for would egeria optimum 0.05kg.m-2 in the HDT of 12 hours result, followed for the HDT of 8 and 4 hours. One concludes that for removal of NT, PT, turbidez and DQO the TDH of 12 hours was what it presented better resulted for both the macrophytes. The water hyacinth produced more biomass that egeria in these conditions in all the TDH. / O presente trabalho teve por objetivo avaliar a eficiência de um sistema de tratamento utilizando macrófitas aquáticas Eichhornia crassipes (aguapé) e Egeria densa (egeria) em três tempos de detenção hidráulica, na remoção de poluentes do efluente de cultivo orgânico de tilápias do Nilo (Oreochromis niloticus) e obter dados sobre a produção de biomassa das macrófitas aquáticas. O trabalho foi realizado na fazenda Paturi, município de Terra Roxa, estado do Paraná, durante o período de 6 semanas. O sistema foi composto por 18 tanques experimentais de 2,00 x 1,00 x 0,65 m de comprimento, largura e profundidade, respectivamente, revestidos com lona de polipropileno. O delineamento foi inteiramente casualizado, 2 macrófitas x 3 tempos de detenção hidráulica (TDH) e 3 repetições. Os TDH utilizados foram de 4 h, vazão de &#8776; 4,15 L.min-1, 8 h, vazão de &#8776; 2,10 L.min-1 e 12 h, vazão de &#8776; 1,40 L.min-1. As amostras foram coletadas na entrada e saída do sistema, em intervalos de cinco dias, avaliando-se o nitrogênio total (NT), fósforo total (PT), amônia, nitrito, nitrato, turbidez, DQO, pH e condutividade elétrica. A temperatura foi medida diariamente. A produção de biomassa foi avaliada ao final do experimento. Para NT, tanto para o aguapé como para a egeria, a maior remoção (P<0,05) foi de 39,90% e 37,38%, respectivamente, observada no TDH de 12 horas, não diferindo do TDH de 8 horas. As melhores remoções de PT (P<0,05) 41,57% e 43,42% foram observadas no TDH de 12 horas para o aguapé e egeria, respectivamente. No caso da turbidez, a maior remoção 62,74% (P<0,05) foi observada no TDH de 12 horas para o aguapé, não diferindo do TDH de 8 horas. Para a egeria o melhor resultado (P<0,05) foi observado no TDH de 12 horas com 81,81%. Para a DQO, tanto o aguapé como a egeria, os melhores resultados de remoção (P<0,05) 63,61% e 62,64% foram observados no TDH de 12 horas, não diferindo do TDH de 8 horas. Para a produção de biomassa o aguapé apresentou os melhores resultados, sendo o maior 8,95 kg.m-2 para o TDH de 4 horas, seguido pelo TDH de 12 e 8 horas. Para a egeria o melhor resultado 0,05 kg.m-2 no TDH de 12 horas, seguido pelos TDH de 8 e 4 horas. Conclui-se que. para remoção de NT, PT, turbidez e DQO, o TDH de 12 horas foi o que apresentou melhor resultado para ambas as macrófitas. O aguapé produziu mais biomassa que a egeria nessas condições em todos os TDH.
80

Chemophysical Characteristics And Application Of Biosorption Activated Media (bam) For Copper And Nutrient Removal In Stormwater Management

Jones, Jamie 01 January 2013 (has links)
For high groundwater table areas, stormwater wet detention ponds are utilized as the preferred stormwater management throughout the state of Florida. Previous research has found that accumulations of nutrients, algae, heavy metals, pesticides, chlorophyll a, fecal coliform bacteria and low concentrations of dissolved oxygen (DO) are common characteristics of stormwater wet detention ponds. Although these pollutant levels are not regulated within the ponds, states are required to compute the pollutant load reductions through total maximum daily load (TMDL) programs to meet the water quality requirements addressed by the Clean Water Act (CWA). In this study, field sampling data of stormwater ponds throughout Florida are presented to identify concentration levels of the main contaminants of concern in the discharge of wet detention ponds. Sampling was done to identify possible sources, in addition to possible removal mechanisms via the use of specific sorption media. Nutrients were found as a main problematic pollutant, of which orthophosphate, total phosphorus, ammonia, nitrate, and total nitrogen were targeted whereas heavy metals exhibited minor concerns. Accumulation of high nutrient concentrations may be mitigated by the adoption of best management practices (BMPs) utilizing biosorption activated media (BAM) to remove phosphorus and nitrogen species through physical, chemical, and biological processes. This study aims to increase overall scientific understanding of phosphorus removal dynamics in sorption media systems via Langmuir and Freundlich isotherms and column studies. The removal of phosphorus (P) was proven effective primarily through chemophysical processes. The maximum orthophosphate adsorption capacities were determined under varying conditions of the media within the columns, which were found up to 0.000534 mg-P adsorbed per gram BAM with influent concentrations of 1 mg∙L -1 orthophosphate in distilled water and 1 hour hydraulic residence time (HRT). When using iv spiked pond water under the same conditions, the adsorption capacity was increased about 30 times to 0.01507 mg-P∙g -1 BAM presumably due to the properties and concentrations of ions affecting the diffusion rate regulating the surface orthophosphate reactions. These equilibrium media uptake values (q) were used to calculate the life expectancies of the media under varying HRT and influent concentrations of treatment. Chemophysical and biological removal capabilities of the media for total nitrogen, ammonia, and nitrate were effective in columns using 1100 g of BAM. In flow-through column conditions, ammonia had a consistent ~95% removal while effluent nitrate concentrations were highly variable due to the simultaneous nitrificationdenitrification processes once an aerobic-anaerobic environment was established. Batch column experiments simulating no-flow conditions within a media bed reactor resulted in orthophosphate removals comparable with the continuous flow conditions, increased total phosphorus effluents indicative of chemical precipitation of orthophosphate, decreased ammonia removal, and increased nitrate removal. Due to a biofilm’s sensitivity to even low copper concentrations and accumulation in ponds, a copper sorption media mix of "green" materials was generated. Freundlich and Langmuir isotherm tests concluded a successful mix resulting in copper removal efficiencies up to 96%.

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