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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.
491

Integration of a combined UASB-ozonation treatment system for cellar effluent degradation

McLachlan, Tania 03 1900 (has links)
Thesis (MSc Food Sc)--Stellenbosch University, 2004. / ENGLISH ABSTRACT: The wine industry significantly contributes to South Africa's water demand and subsequent pollution of the limited resource. Wastewater is produced throughout the year with an increase in volume and organic load during the vintage season. Anaerobic digestion (AD), specifically the upflow anaerobic sludge bed (UASB) technology has been shown to be feasible in the treatment of cellar wastewater. However, the legal standard for chemical oxygen demand (COD) for disposal in a natural water resource (75 rnq.L") is often not met. The aim of the study was to conduct a laboratory-scale investigation into the feasibility of combining pre- and post-ozonation processes with AD in order to achieve a final COD closer to the legal disposal limit. While acclimatising an UASB bioreactor containing mixed anaerobic granules to a cellar wastewater with a pH set at 8.0, stable-state conditions were not reached. Sucrose additions to the substrate, increased substrate loads, heattreatment of the substrate and an addition of isolated cellar effluent bacteria to facilitate degradation prior to AD, were all unsuccessful in maintaining stable-state in terms of COD removal efficiency. Once the substrate pH was re-set to 7.5, the reactor stabilised. The lowest efficient operational pH was found to be 5.73 resulting in a COD removal of 88% at a substrate COD < 5 000 rnq.L". At a substrate pH of 6.0, the lowest efficient operational hydraulic retention time (HRT) and corresponding organic loading rate (OLR) were 19.7 hand 9.75 kg COD.m-3d-1 , respectively, with the COD removal being maintained around 84%. The reactor effluent still had a final COD of 1280 rnq.L", which was well above the legal South African limit. Dominant bacteria were isolated from raw cellar wastewater and identified as Acinetobacter haemolyticus, Burkholderia cepacia and Cryseomonas luteola. In order to investigate the possibility that ozonation improved biodegradability, the growth of the isolates at 35°C was monitored over 24 h in sterile ozonated and non-ozonated substrates from the vintage and non-vintage seasons. All the isolates increased by at least 1.5 log cycles in the control substrates from both seasons. Ozonation of the wastewater batches for 10 min at a rate of 73 rnq.L" led to slightly increased growth of the inoculants in the substrate batch from the vintage season. For the substrates from the non-vintage season, ozonation had an inhibitory effect on the bacterial growth. A 5 min ozonation treatment at a concentration of 73 rnq.L" was found to be optimal for both a pre- and post-treatment to UASB-treatment of cellar wastewater. Both UASB treatment and ozonation were effective in reducing the COD by 85% and 20%, respectively. The COD reduction was improved to 88% when UASB treatment was combined with post-ozonation. The total reduction in total suspended solids (TSS) for the combined process was 97%, compared to 80% for UASB and 73% for an ozone treatment alone. The reduction for volatile suspended solids (VSS) was 98% compared to 81% for UASB and 73% for the ozone treatment alone. The total reduction when using a pre-ozonation UASB treatment combination was an average of 86% for COD. The TSS and VSS were both reduced by 95%. Biogas production increased from 1.4 L.d-1 to 3.8 L.d-1 when an ozonated wastewater was used as substrate. When the UASB treatment was combined with both a pre- and post-ozonation treatment process, the COD was reduced by 89% while TSS and VSS were both reduced by 99%. This study showed that pre- and post-ozonation treatment processes could successfully be utilised to improve UASB treatment of cellar wastewater. Although the legal limits for discarding into a natural resource were not met, significant progress was made in reducing COD levels. Cellar wastewaters do however, vary according to season and the wastewater composition could affect the efficiency of a pre-ozonation process. / AFRIKAANSE OPSOMMING: Die wynindustrie maak "n beduidende bydrae tot die eise wat aan Suid-Afrika se waterbronne gestel word en gevolglik die besoedeling van die beperkte hulpbron. Afloopwater, wat in volume en organiese lading gedurende die parstyd toeneem, word reg deur die jaar opgelewer. Anaërobiese vertering (AV), spesifiek die "Upflow anaerobic sludge blanket" (UASB) tegnologie, is alreeds suksesvol gebruik om kelderafloop te behandel. Die wetlike vereiste vir chemiese suurstof behoefte (CSB) vir storting in "n natuurlike hulpbron (75 rnq.L"), word egter dikwels nie bereik nie. Die doel van die studie was om in "n laboratorium-skaal ondersoek AV te kombineer met voor- en na-osoneringsprossesse, om sodoende te poog om "n CSB nader aan die wetlike standaard te verkry. Terwyl"n UASB bioreaktor wat gemengde anaerobiese granules bevat het, geakklimatiseer is tot kelderafloop met "n pH gestel tot 8.0, kon stabiele toestande nie bereik word nie. Die byvoeging van sukrose tot die substraat, verhoogde substraatladings, hitte-behandeling van die substraat en die byvoeging van geïsoleerde kelderafloop bakterië om substraatafbraak voor AV aan te help, was onsuksesvol om stabiliteit in terme van CSB-verwydering, te handhaaf. "n Verstelling van die substraat pH na 7.5, het gelei tot reaktorstabiliteit. By die laagste doeltreffende bedryfs-pH van 5.73 en substraat CSB < 5 000 rnq.L", was die CSB-verwydering 88%. By "n substraat pH van 6.0 was die laagste doeltreffende bedryfs-hidroliese retensie tyd en -organiese ladingstempo 19.7 h en 9.75 kg CSB.m-3d-1, onderskeidelik, terwyl die CSB verwydering rondom 84% gehandhaaf is. Die CSB van die reaktoruitvloesel van 1 280 rnq.L", was steeds ver bo die wetlike vereiste. Dominante bakterië is uit kelderafloop geïsoleer en as Acinetobacter haemolyticus, Burkholderia cepacia en Cryseomonas luteola, geïdentifiseer. Die moontlikheid dat osonering bioafbreekbaarheid bevorder, is ondersoek deur die groei van die isolate by 35°C oor 24 h in steriele geësoneerde en ongeësoneerde substrate te monitor. Die substrate is berei vanaf kelderafloop wat in die parsseisoen sowel as die nie-parsseisoen versamel is. AI die isolate het met ten minste 1.5 log siklusse in die kontrole substrate van beide seisoene, vermeerder. Vir die kelderafloop wat in die parsseisoen versamel is, het osonering vir 10 min teen 73 rnq.L" gelei tot effens verbeterde groei van die innokulante. Osonering het 'n onderdrukkende effek op die groei van bakterië in die afloopwater versamel in die nie-parsseisoen, gehad. Osonering vir 5 min teen 'n konsentrasie van 73 rnq.L" is as optimum vir beide voor- en na-osoneringsbehandeling tot UASB-behandeling van die kelderafloop, gevind. UASB-behandeling en osonering het die CSB met 85 en 20% onderskeidelik, verminder. Die vermindering kon tot 88% verhoog word wanneer UASB-behandeling met na-osonering gekombineer is. Die vermindering in totale gesuspendeerde vastestowwe (TGV) vir die gekombineerde proses was 97%, in vergelyking met 80% vir UASB- en 73% vir osoonbehandeling alleen. Die vermindering in vlugtige gesuspendeerde vastestowwe (VGV) was 98% in vergelyking met 81% vir UASB- en 73% vir osoonbehandeling alleen. Die totale CSB verwydering vir 'n voor-osonerings UASB kombinasie was gemiddeld 86%. Die TGV en VGV is beide met 95% verminder. Biogasproduksie het ook vermeerder vanaf 1.4 L.d-1 tot 3.8 L.d-1 toe geosoneerde afloopwater as substraat gebruik is. Die kombinasie van UASB-behandeling met voor-osonering, sowel as na-osonering het gelei tot 'n CSB-verwydering van 89% terwyl TGV en VGV beide met 99% verminder is. Hierdie studie het getoon dat voor- en na-osonering suksesvol gebruik kan word om UASB-behandeling van kelderafloop te verbeter. Hoewel wetlike vereistes vir storting in 'n natuurlike hulpbron nie bereik is nie, is beduidende vordering gemaak in die verlaging van CSB-vlakke. Die verskil in die samestelling van kelderafloop gedurende die onderskeie seisoene, kan egter die doeltreffendheid van die voor-osoneringsproses beïnvloed.
492

Optimising coagulation and ozone pre-treatments and comparing the efficacy of differently pre-treated grain distillery wastewaters in an upflow anaerobic sludge blanket (UASB) reactor

Robertson, Louise 04 1900 (has links)
Thesis (MScFoodSc)--Stellenbosch University, 2014. / ENGLISH ABSTRACT: Large volumes of high strength wastewater are generated annually by distilleries. Treatment of this wastewater is essential to increase its reuse potential. Anaerobic digestion (AD) has been widely applied as high strength wastewater treatment. Additionally, grain distillery wastewater (GDWW) is high in fats, oils and grease (FOG) which can cause problems during AD. Pre-treatment is therefore often required to make the AD process more efficient. The overall objective of this study was to investigate the operational efficiency of upflow anaerobic sludge blanket (UASB) reactors while treating GDWW as substrate. The first aim was to investigate the pre-treatment of the GDWW specifically for the removal of FOG by evaluating the effect of pH adaption, coagulant concentration and ozone (O3) dosages on the FOG reduction efficiency. Secondly, the effect of two different pre-treatments (only coagulant and coagulant and ozone) on the subsequent UASB treatment step was investigated. The pH of raw GDWW (pH 3.4) was adapted to three different pH values (5.0, 6.0, and 7.0) and the coagulant, aluminium chlorohydrate (ACH) (140 mg.L-1), was added. To make the process more economically viable, the lowering the coagulant concentration (to 100 mgACH.L-1) was also investigated. Optimal reductions for chemical oxygen demand (COD) (33.2% ± 4.93), total suspended solids (TSS) (91.9% ± 1.73) and FOG (84.1% ± 1.98) were, however, achieved at a higher coagulant concentration of 140 mgACH.L-1, and at a wastewater pH of 7.0. The effect of additional ozone treatment was also investigated. Maximum reductions for the ozone treatment were obtained at 100 mgO3.L-1 for COD (3.6% ± 4.08), and at 900 mgO3.L-1 for TSS (27.7% ± 5.58) and FOG (23.9% ± 1.83). The ozone treatment was most efficient for FOG reduction (in terms of mg FOG reduced per mg ozone) at 100 mgO3.L-1. An ozone dosage of 300 mgO3.L-1, was decided on based on economic feasibility, findings in literature on toxicity of ozone and the potential degradation of recalcitrant compounds at this dosage. The final pre-treatment thus included pH adaption to 7.0, coagulant dosage of 140 mgACH.L-1, and an ozone dosage of 300 mgO3.L-1. The second part of this study involved the operation of two 2 L laboratory scale UASB reactors for 277 days. The substrate of the first reactor contained GDWW that had only undergone coagulant pre-treatment (Rcontrol), while the substrate of the second UASB reactor consisted of GDWW that had undergone coagulant and ozone pre-treatment (Rozone). Both reactors treated the pre-treated GDWW successfully at ca. 9 kgCOD.m-3d-1. COD reductions of 96% for Rcontrol and 93% for Rozone, were achieved. FOG reductions (%) showed variations throughout the study and maximum reductions of 88% and 92% were achieved for Rcontrol and Rozone, respectively. The Rozone produced more biogas, but the methane content was similar for both reactors. The additional ozone pre-treatment did not show any added benefits to the reactor performance results. UASB granule washout in Rcontrol did, however, suggest possible toxicity of unsaturated fatty acids present in the non-ozonated substrate. The feasibility of FOG removal was shown as both reactors successfully treated pre-treated GDWW. Ozonation, after a coagulant dosage, which resulted in further reduction in the FOG content of the GDWW, is thus not essential to ensure the success of an anaerobic digestion step. Ozonation of the pre-treated GDWW could, however, be beneficial to gas production and the efficiency of a tertiary biological process. / AFRIKAANSE OPSOMMING: Groot volumes hoë-sterkte afloopwater word jaarliks deur distilleerderye opgelewer. Die behandeling van hierdie afloopwater is noodsaaklik om die hergebruiksmoontlikheid daarvan te verhoog. Die toepassing van anaërobiese vertering (AV) is wydverspreid in hoë-sterkte afloopwaterbehandeling. Graandistillerings-afloopwater (GDAW) is boonop hoog in vette, olies en ghries (VOG), wat probleme kan veroorsaak tydens AV. Voorbehandeling word dus dikwels verlang om die AV meer doeltreffend te maak. Die oorhoofse doelstelling van hierdie studie was om die doeltreffendheid van opvloei-anaërobieseslykkombers- (OAS-) reaktore wat GDAW as substraat behandel, te ondersoek. Die eerste mikpunt was om die voorbehandeling van die GDAW, te ondersoek vir die verwydering van VOG. Dit is uitgevoer deur die uitwerking van pH aanpassing, koagulantkonsentrasie en osoon(O3)dosis op VOG vermindering te evalueer. Tweedens is die uitwerking van twee verskillende voorbehandelings (slegs koagulant asook koagulant en osoonbehandeling) op die opvolgende OAS-behandelingsstap ondersoek. Die pH van rou GDAW (pH 3.4) is aangepas tot drie verskillende pH waardes (5.0, 6.0 en 7.0) en die koagulant, aluminium-chlorohidraat (ACH), is bygevoeg (140 mg.L-1). Om die proses meer ekonomies uitvoerbaar te maak is ‘n verlaagde koagulantkonsentrasie (verlaag tot 100 mgACH.L-1) ook ondersoek. Die optimale afnames vir chemiese suurstofvereiste (CSV) (33.2% ± 4.93), totale oplosbare vastestowwe (TOV) (91.9% ± 1.73) en VOG (84.1% ± 1.98) is egter bereik teen ‘n hoër koagulant konsentrasie van 140 mgACH.L-1, en teen ‘n afloopwater-pH van 7.0. Die uitwerking van ‘n bykomende osoonbehandeling is ook ondersoek. Die hoogste afnames tydens die osoonbehandeling is bereik teen 100 mgO3.L-1 vir CSV (3.6% ± 4.08), en teen 900 mgO3.L-1 vir TOV (27.7% ± 5.58) en VOG (23.9% ± 1.83). Die osoonbehandeling was mees doeltreffend vir VOG (in terme van mg VOG verwyder per mg osoon) teen 100 mgO3.L-1. Daar is besluit op ‘n van 300 mgO3.L-1, as gevolg van die ekonomiese uitvoerbaarheid, bevindinge in literatuur vir die toksisiteit van osoon, en die moontlike afbraak van moeilik-afbreekbare komponente teen hierdie dosis. Die finale voorbehandeling het dus bestaan uit ‘n aanpassing van die afloopwater-pH na 7.0, ‘n koagulantdosis van 140 mgACH.L-1, en ‘n osoondosis van 300 mgO3.L-1. Tydens die tweede gedeelte van hierdie studie is twee 2 L laboratoriumskaal OAS reaktore bedryf vir 277 dae. Die substraat van die eerste reaktor het GDAW bevat wat slegs ‘n koagulant-voorbehandeling ondergaan het (Rkontrole), terwyl die substraat van die tweede OAS-reaktor GDAW bevat het wat koagulant- en osoon-voorbehandeling ondergaan het (Rosoon). Beide reaktore het die voorbehandelde-GDAW suksesvol behandel teen ‘n organieseladingstempo van ca. 9 kgCSV.m-3d-1. Afnames in CSV van 96% vir Rkontrole en 93% vir Rosoon, is bereik. Tydens die studie is deurlopende wisseling in VOG verwydering (%) waargeneem, en die hoogste verwyderings wat bereik is, is onderskeidelik 88% en 92% vir Rkontrole en Rosoon. Die Rosoon het meer biogas geproduseer, maar die metaanpersentasie was soortgelyk vir beide reaktore. Die osoon-voorbehandeling het nie enige toegevoegde voordele getoon in die reaktorprestasie resultate nie. Die uitwas van die OAS-granules vir die Rkontrole het egter moontlike toksisiteit van onversadigdevetsure aangedui, wat moontlik teenwoordig kon wees in die nie-geösoneerde substraat. Die uitvoerbaarheid van VOG verwydering is getoon aangesien beide reaktore voorbehandelde GDAW suksesvol behandel het. Osonering, wat verdere afname in die VOG inhoud van GDAW teweeggebring het (na ‘n koagulant dosis), is dus nie noodsaaklik vir die suksesvolle verloop van ‘n anaërobiese-verteringsstap nie. Osonering van die voorbehandelde GDAW kan egter voordelig wees vir gasvorming, en kan ook verder die doeltreffendheid van ‘n tersiêre biologiese behandeling verhoog.
493

Remoção de matéria orgânica em tanque séptico com biomassa aderida / Removal of organic matter in a septic tank with adhered biomass

Silva, Jaqueline dos Santos 21 February 2018 (has links)
No Brasil cerca de 50,3% da população é atendida por rede coletora de esgoto, do qual apenas 42,7% é tratado. Uma parcela de 12% da população total do país utiliza fossa séptica para o tratamento do esgoto gerado em suas residências. Apesar de suas vantagens, os tanques sépticos apresentam moderada remoção de matéria orgânica, girando em torno de 50%. Nesse sentido, vê-se a necessidade do aprimoramento desse sistema a fim de melhorar sua eficiência. O aumento da concentração de biomassa microbiana no sistema por meio da inserção de material suporte é um método frequentemente utilizado com este propósito, pois isso permite que os microrganismos fiquem por mais tempo dentro do sistema, aumentando seu tempo de contato com o esgoto e, consequentemente, elevando a eficiência de degradação da matéria orgânica. A garrafa PET tem sido estudada como material suporte em tanque séptico. O uso desse material em sistemas individuais de tratamento de esgoto está relacionado com o desenvolvimento de uma técnica sustentável e acessível a comunidades sem acesso à rede coletora. O objetivo desta pesquisa foi introduzir material suporte em tanque séptico em escala de bancada, o qual foi operado em quatro etapas: Etapa 1 (sem material suporte), Etapa 2 (50% de ocupação), Transição (sem material suporte) e Etapa 3 (10% de ocupação). O material suporte utilizado foram tiras de garrafa PET lixadas, com 1,5 cm de largura e 15,5 cm de comprimento. Os parâmetros de monitoramento, avaliados no esgoto afluente e efluente, foram: pH, alcalinidade total, ácidos graxos voláteis (AGV), DQO total e filtrada e série de sólidos. A concentração de microrganismos aderidos ao material suporte nas Etapas 2 e 3 foi monitorada por meio da concentração de proteínas (PT), polissacarídeos (PST) e sólidos totais voláteis aderidos (STVA). O resultado do monitoramento de pH, alcalinidade e AGV indicou estabilidade do sistema em todas as etapas de operação, sendo que a presença de material suporte não interferiu nesses resultados. A inserção de material suporte contribuiu para o aumento da eficiência do sistema, sendo que as maiores médias de remoção de DQOT e DQOF foram na Etapa 3 (77,9% e 74,4%) e as menores na Etapa 1 (49,7% e 40,5%). Em relação aos sólidos, a Etapa 2 apresentou as melhores eficiências de remoção de sólidos totais (42,1%) e sólidos em suspensão totais (82,3%) e a Etapa 3, as de sólidos dissolvidos totais (33,2%) e voláteis (87,4%). As análises de PT, PST e STVA indicaram a maior concentração de biomassa microbiana no material suporte na Etapa 2, fato esse que não refletiu na melhor eficiência de remoção de matéria orgânica. Conclui-se que a inserção de tiras de garrafa PET como material suporte em tanque séptico apresentou melhoria na eficiência de remoção de matéria orgânica, sendo que o percentual de ocupação de 10% apresentou os melhores resultados. / In Brazil about 50,3% of the population is served by a sewage collection network, of which only 42,7% is treated. A 12% share of the country’s total population uses septic tank to treat sewage generated in their homes. Despite their advantages, septic tanks present moderate removal of organic matter, spinning around 50%. In this sense, it is necessary to improve this system in order to improve its efficiency. The increase of microbial biomass concentration in the system by the insertion of support material is a method frequently used for this purpose, as this allows the microorganisms to remain for longer in the system, increasing their time of contact with the sewage and, consequently, increasing the efficiency of organic matter degradation. The PET bottle has been studied as a septic tank support material. The use of this material in individual sewage treatment systems is related to the development of a technique that is sustainable and accessible to communities without access to the collection network. In this sense, the objective of this research was the introduction of support material in a septic tank in a bench scale, which was operated in four stages: Step 1 (without support material), Step 2 (50% occupation), Transition (without support material) and Step 3 (10% occupation). The support material used were sands PET bottle strips, with 1,5 cm wide and 15,5 cm long. The monitoring parameters, evaluated in the influent and effluent sewage were: pH, total alkalinity, volatile fatty acids (VFA), total and filtered COD and solid series. The concentration of microorganisms adhered to the support material in Stages 2 and 3 was monitored by means of the concentration of proteins (PT), polysaccharides (PST) and adhered total volatile solids (STVA). The results of the monitoring of pH, alkalinity and VFA indicated stability of the system in all stages of operation, and the presence of support material did not interfere in these results. The insertion of support material contributed to increase the efficiency of the system, and the highest removal rates of DQOT and DQOF were in Step 3 (77.9% and 74.4%) and the lowest in Step 1 (49.7% % and 40.5%). In relation to solids, Step 2 presented the best removal efficiencies of total solids (42.1%) and total suspended solids (82.3%), and Step 3, total dissolved solids (33,2%) and volatile (87,4%). The analyzes of PT, PST and STVA indicated the highest concentration of microbial biomass on support material in Step 2, a fact that did not reflect the better efficiency of organic matter removal. It was concluded that the insertion of strips of PET bottle as a support material in septic tank showed an improvement in the organic matter removal efficiency, and the occupancy percentage of 10% presented the best results.
494

Avaliação do uso de coagulantes naturais no polimento de efluente de abatedouro e frigorífico de suínos / Evaluation of natural coagulants in the polishing treatment of swine slaughterhouse wastewater

Bortolatto, Rubiane 02 June 2017 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / A coagulação, um processo importante no tratamento convencional de efluentes, promove a retirada de partículas leves demais para sedimentarem por ação da gravidade (coloides). A sedimentação destas partículas torna-se possível com a adição de agentes coagulantes, geralmente sais metálicos. Entretanto, o grande inconveniente no uso destes sais são os resíduos metálicos que permanecem no lodo, e que podem contaminar o solo. Agentes coagulantes à base de polieletrólitos orgânicos têm se mostrado interessantes pela sua capacidade de retirar matéria orgânica de efluentes. Este trabalho objetivou testar a eficiência de dois polieletrólitos naturais, quitosana e Tanfloc®, como coagulantes, para redução de DQO, turbidez e cor aparente de efluente advindo de um abatedouro e frigorífico de suínos, e de compará-la com a eficiência do cloreto férrico. A sequência de ensaios, conduzidos em Jar Test, foi realizada segundo planejamento experimental pré-definido para cada um dos coagulantes, com planejamento fracionado seguido de DCCR. A quitosana promoveu aumento considerável da DQO, ao invés de sua redução, mostrando-se ineficaz na redução desta resposta. Entretanto, como auxiliar de coagulação a quitosana favoreceu a formação de flocos maiores. O Tanfloc® proporcionou formação de flocos grandes em pH básico (7,75) e flocos pequenos em pH ácido (5,25). Em condição ótima e em pH básico, ainda para o Tanfloc®, a redução máxima foi de 86% para turbidez e 34% para cor aparente. Em pH ácido, a melhor redução foi de 96% para turbidez e 78% para cor aparente. A redução conseguida para DQO foi de cerca de 50%, independentemente do pH aplicado. Estes resultados foram satisfatórios e condizentes com o esperado para o coagulante Tanfloc®. Quanto ao cloreto férrico, este apresentou, de forma geral, um desempenho inferior ao Tanfloc®. Os resultados mostram que o Tanfloc® foi eficaz no papel de coagulante primário, substituindo, com vantagens, o cloreto férrico no tratamento de coagulação, floculação e sedimentação do efluente de estudo. / Coagulation, an important process in the conventional treatment of effluents, promotes the removal of particles too light to sediment by gravity action (colloids). The settling of these particles becomes possible with the addition of coagulating agents, generally metal salts. However, the major drawback in the use of such salts are metallic residues remaining in the sludge, which can contaminate soil. Coagulant agents based on organic polyelectrolytes have been interesting for their ability to remove organic matter from effluents. This study aimed to test the efficiency of two natural polyelectrolytes, chitosan and Tanfloc®, As coagulants, for the reduction of COD, turbidity and apparent colour of effluent coming from a pig slaughterhouse, and to compare it with the efficiency of ferric chloride. The sequence of tests, conducted in Jar Test, was performed according to a predefined experimental design for each of the coagulants, with fractional planning followed by DCCR. Chitosan promoted a considerable increase in COD, rather than its reduction, proving ineffective in reducing this response. However, as a coagulation aid, chitosan favored the formation of larger flakes. Tanfloc® provided formation of large flakes at basic pH (7.75) and small flakes at acid pH (5.25). In optimum condition and at basic pH, a maximum reduction of 86% for turbidity and 34% for apparent colour was obtained. At acid pH, the reduction achieved for the responses was 96% for turbidity and 78% for apparent colour. The COD reduction was about 50% regardless of the pH. These results were satisfactory and consistent with that expected for the coagulant. Regarding ferric chloride, it generally presented a lower performance than Tanfloc®. The results showed that Tanfloc® performed very well the role of primary coagulant, favorably replacing ferric chloride in the treatment of coagulation, flocculation and sedimentation of the study effluent.
495

Preparação, caracterização e aplicação de híbridos de montmorilonita-alginato-nanopratas na desinfecção de efluentes industriais para águas de reuso

Lovatel, Rosa Helena 24 September 2014 (has links)
Diferentes técnicas têm sido desenvolvidas para eliminar micro-organismos de efluentes industriais e melhorar a sua qualidade final. Dentre elas, o uso de nanopartículas de prata (AgNPs) ancoradas em montmorilonita (MMT) tem demonstrado bons resultados. Neste contexto, este estudo teve por objetivo preparar híbridos de alginato de sódio (ALG) e MMT, com AgNPs ancoradas, visando sua posterior aplicação na desinfecção de efluentes industriais para águas de reuso. Inicialmente, as AgNPs foram sintetizadas por meio da redução química de íons prata com boroidreto de sódio, na presença de citrato de sódio. Em seguida, uma suspensão contendo AgNPs, MMT e ALG foi preparada. Os híbridos de MMT-ALG-AgNPs foram obtidos a partir do gotejamento da suspensão em uma solução aquosa de cloreto de cálcio (4,0% m/v). As AgNPs, assim como os híbridos, foram caracterizados por meio das técnicas de espectroscopia de absorção na região do ultravioleta e visível (UV-Vis), microscopia eletrônica de transmissão (MET) e de varredura (MEV), espectroscopia no infravermelho com transformada de Fourier (FT-IR) e difração de raios X (DRX). O conjunto de resultados confirmou a presença da MMT, com as AgNPs ancoradas em formato esférico, dispersa na matriz de alginato. Posteriormente, foi realizado o ensaio de difusão em ágar com dois tipos de micro-organismos (Escherichia coli e Staphylococcus aureus) para se verificar o potencial bactericida desses materiais. Os ensaios mostraram que houve a formação de zonas de inibição (ZOI) para ambas as bactérias. Os híbridos foram então utilizados na desinfecção de um efluente industrial e os resultados indicaram uma redução de 98,5% em termos de coliformes totais. Por fim, o efluente industrial foi submetido a outro processo de desinfecção utilizando radiação ultravioleta (UV), que é muito comum no tratamento de águas e efluentes, com a finalidade de comparar os resultados obtidos pelos dois métodos. Verificou-se que o percentual de remoção de coliformes totais, em relação ao tempo de contato, foi aproximadamente 16% maior no tratamento com os híbridos do que com a radiação UV, confirmando o potencial do material para o objetivo proposto. / Submitted by Ana Guimarães Pereira (agpereir@ucs.br) on 2015-03-04T17:25:40Z No. of bitstreams: 1 Dissertacao Rosa Helena Lovatel.pdf: 7996972 bytes, checksum: 8c1966fc85def630979bd727eb3dbdde (MD5) / Made available in DSpace on 2015-03-04T17:25:40Z (GMT). No. of bitstreams: 1 Dissertacao Rosa Helena Lovatel.pdf: 7996972 bytes, checksum: 8c1966fc85def630979bd727eb3dbdde (MD5) / Different techniques have been developed to eliminate microorganisms from industrial wastewater and improve its final quality for reuse. Among them, the use of silver nanoparticles (AgNPs) anchored on montmorillonite (MMT) has shown good results. In this context, the aim of this study was to prepare hybrid materials from sodium alginate (ALG) and MMT, decorated with AgNPs, for application in the disinfection of industrial wastewater for reuse. Initially, AgNPs were synthesized by chemical reduction of silver ions with sodium borohydride in the presence of sodium citrate. Then, a suspension containing AgNPs, MMT, and ALG was prepared. The hybrid MMT-ALG-AgNPs was obtained from dripping the suspension in an aqueous solution of calcium chloride (4.0% w/V).The AgNPs and the hybrids were characterized by UV-visible absorption spectroscopy (UV-Vis), transmission electron microscopy (TEM), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FT-IR), and X-ray diffraction (XRD).The set of results confirmed the presence of MMT decorated with AgNPs of spherical shape dispersed in the ALG matrix. The evaluation of the bactericidal potential of the hybrids was performed by the agar diffusion assay with two types of micro-organisms (Escherichia coli and Staphylococcus aureus). The tests evidenced the formation of a prominent zone of inhibition (ZOI) for both bacteria. The hybrids were then used in the disinfection of an industrial wastewater. The results indicated a reduction of up to 98.5% of total coliforms. For comparison bases, the industrial wastewater was subjected to another disinfection process using ultraviolet radiation (UV), which is very common in the treatment of water and wastewater. It was found that the removal of total coliforms with the hybrids was approximately 16% higher than the UV radiation, thus confirming the potential of these materials for the purpose of this work.
496

Avaliação de bactérias nitrificantes em lodos ativados de quatro estações de tratamento de diferentes efluentes industriais

Pauletti, Carla Maria 05 August 2016 (has links)
Os sistemas de lodos ativados se destacam pelo fato de oferecerem a possibilidade de remoção satisfatória de nutrientes como nitrogênio e fósforo, com poucos requisitos de área. Para aperfeiçoar esse processo de remoção, o sistema pode ser otimizado a fim de alcançar satisfatórias condições de pH, temperatura, aeração, entre outros. As bactérias presentes no lodo ativado são capazes de transformar e remover o nitrogênio através dos processos de nitrificação e desnitrificação. As reações de nitrificação são catalisadas por diferentes gêneros de bactérias autotróficas, entres os quais Nitrosomonas, Nitrobacter, Nitrospira, Nitrococcus. Existem evidências mais recentes de que estas reações de nitrificação podem, em certa medida, também ser catalisadas por organismos heterotróficos. Assim, a identificação das bactérias presentes em lodos ativados de Estações de Tratamento de Efluentes (ETE), bem como o estudo dos fatores que podem ou não influenciar na eficiência do processo de remoção de nutrientes, é muito importante para a otimização do sistema. As análises físico-químicas e, posterior, análises da composição bacteriana foram realizadas em amostras de afluente, efluente e de lodo de quatro diferentes estações de tratamento. As coletas foram realizadas em ETE de dois abatedouros de aves, de uma indústria de embalagens de papel e de um hospital particular. As amostras analisadas mostraram resultados pouco similares entre si, evidenciando diferenças nos processos de nitrificação e desnitrificação conforme a ETE de origem. Os resultados encontrados para as análises físico-químicas nas amostras estudadas estiveram de acordo com os parâmetros normalmente encontrados para efluentes industriais e de acordo com os exigidos pela legislação (CONAMA, 2011), com exceção de apenas uma amostra (hospital), que teve um valor de nitrogênio amoniacal (21,23 mg/L) na saída do sistema acima do valor máximo permitido pela legislação vigente (20 mg/L). A eficiência de remoção de DQO em todas as estações de tratamento esteve na faixa entre 67,5% e 97,8%. A amostra da ETE da Indústria de Embalagens de Papel foi a que demonstrou maior eficiência de remoção de DQO (97,8%), enquanto que uma das amostras da ETE do Hospital Particular, que apresentou a maior DQO na entrada do sistema, foi a que obteve menor eficiência de remoção (67,5%). A remoção de nitrogênio amoniacal foi observada, com exceção de uma amostra, em todas as demais, e sua eficiência de remoção foi bastante variável nas amostras, com valores considerados satisfatórios para o parâmetro estudado (99,7%) e abaixo do esperado para sistemas de lodos ativados (24,6%). A menor eficiência de remoção de nitrogênio amoniacal (24,6%) foi encontrada para uma amostra da ETE Hospital, enquanto a maior eficiência se observou para a amostra da ETE Embalagens de Papel (99,7%). As amostras de lodo foram analisadas molecularmente através de nested PCR e DGGE, com posterior sequenciamento genético. Os primers utilizados na técnica de nested PCR foram: 11f e 1492r (primers universais), NIT3r (Nitrobacter), Nos1225r (Bactérias oxidadoras de amônio), Ntspa685r (Nitrospira), sendo o primer Eub338f utilizado em conjunto com os primers específicos. Já o PCR realizado para o DGGE foi realizado utilizando-se os primers 968F GC e 1392r. As análises moleculares demonstraram que as bactérias mais comuns nos processos de tratamento por lodos ativados (Bactérias oxidadoras de amônio, nitrobacter e nitrospira) estiveram presentes (pelo menos um dos gêneros) em quase todas as amostras testadas por PCR. A amostra que mostrou maior eficiência de remoção de DQO e nitrogênio amoniacal teve, também, resultado positivo para todos os primers utilizados (Bactérias oxidadoras de amônio, nitrobacter e nitrospira) na técnica de PCR, sugerindo que o processo de nitrificação foi satisfatório. Das amostras que tiveram resultado positivo para as amplificações com primers específicos para nitrificantes, apenas uma teve correspondência de resultado positivo no sequenciamento genético (Bactérias oxidadoras de amônio). / Submitted by Ana Guimarães Pereira (agpereir@ucs.br) on 2016-11-23T17:48:34Z No. of bitstreams: 1 Dissertacao Carla Maria Pauletti.pdf: 2032023 bytes, checksum: 05c1e6ec8f9dadc338303f4fd9581a5d (MD5) / Made available in DSpace on 2016-11-23T17:48:34Z (GMT). No. of bitstreams: 1 Dissertacao Carla Maria Pauletti.pdf: 2032023 bytes, checksum: 05c1e6ec8f9dadc338303f4fd9581a5d (MD5) Previous issue date: 2016-11-23 / PETROBRAS, Brasil.
497

Avaliação do desempenho de sistemas de zona de raízes (wetlands construídas) em escala piloto aplicados ao tratamento de efluente sintético

Andrade, Helisson Henrique Borsato de 30 March 2012 (has links)
CAPES / Arranjos tecnológicos que integram sistemas de zona de raízes apresentam-se como uma opção plausível para adequação de efluentes, devido principalmente a sua simplicidade construtiva, baixo custo de implantação/operação e eficiência na remoção de poluentes. Estes sistemas atuam como filtros biológicos cultivados com macrófitas aquáticas, aplicados ao tratamento de esgotos domésticos e industriais. O presente estudo teve por objetivo a construção e o monitoramento de dois sistemas pilotos de tratamento de esgotos por zonas de raízes de fluxo hidráulico vertical livre e afogado, montados em recipientes plásticos com volume total de 220L cada. Neles foi cultivada a espécie vegetal Canna x generalis L.H Bailey (cana- indica), planta heliófita rizomatosa, com folhagens ornamentais e de inflorescências coloridas, cultivada sobre meio suporte com camadas de brita e areia. Os sistemas foram alimentados com substrato sintético tendo glicose como fonte de carbono, sob taxa hidráulica de aplicação de 125,8 L.m-2.dia-1 e matéria orgânica em termos de DQO de 300,93± mg.L-1. O sistema de fluxo afogado apresentou eficiências na remoção de Nitrogênio Total Kjeldahl, DQO e PO 4 de, 55±17%, 95±6% e 46±11% respectivamente. No sistema de fluxo livre as eficiências para remoção de Nitrogênio Total Kjeldahl, DQO e PO4 foram de 57±11%, 96±6% e 41±11%, demonstrando elevada remoção de matéria orgânica e nutrientes para os dois modelos estudados. / Technological arrangements that integrate systems root zone are presented as plausible option for effluents treatment, mainly because of their simplicity in construction, low cost of implementation/operation and efficiency in removing pollutants. These systems act as biological filters planted with macrophytes, applied to the treatment of domestic and industrial sewage. The present study aimed at the construction and monitoring of two pilot systems for sewage treatment of the roots zones of free vertical hydraulic flow and drowned, mounted in plastic containers with a total volume of 220L each. They were cultivated plant species Canna x generalis LH Bailey (cana indica), heliophytic rhizomatous plant with ornamental foliage and colorful flowers, grown on the support medium with layers of gravel and sand. The systems were fed synthetic substrate with glucose as carbon source, under hydraulic application rate of 125,8 L.m-2.day-1 an organic material and in terms of COD of 300,93± mg.L-1. The drowned system flow had removal efficiencies of Total Kjeldahl Nitrogen, COD and PO4 de, 55±17%, 95±6% e 46±11%respectively. In the system of free flow efficiencies for Total Kjeldahl Nitrogen removal, COD and PO4 were 57 ± 11%, 96 ± 6% and 41 ± 11%, showing high removal of organic matter and nutrients for the two models studied.
498

Investigation of anaerobic up-flow batch reactor for treatment of greywater in un-sewered settlements.

Muanda, Christophe January 2009 (has links)
Masters Thesis / Un-sewered settlements are provided with the basic water and sanitation systems that comprise, in most cases, of dry sanitation and standpipes. Substantial amounts of wastewater (including greywater) generated from households are discarded untreated into streets, open spaces between shacks, streams and rivers due to the lack of adequate disposal or treatment infrastructures. The negative impacts from unsafe disposal of greywater generated in un-sewered settlements affect both human health and the general environment. Several treatment technologies ranging from the simplest to the more sophisticated have been developed and made available for consideration to deal with the adverse impacts caused by the unsafe discharge of greywater. Some of these treatment technologies have been implemented successfully in certain developing countries worldwide. Amongst these is the anaerobic up-flow batch reactor (AnUBR) which was successfully used for the first time to treat greywater from sewered areas in Jordan, Lebanon and Sri Lanka. The AnUBR has emerged as a localised greywater treatment technology alternative to conventional treatment methods in areas not served by sewer networks. This technology holds promise because of its simplicity of design, high pollutant removal efficiency, absence of energy or chemical consumption, ease with which it can be implemented, cost effectiveness, and low operation and maintenance costs. This technology was originally developed for treating sewage and high strength greywater from hotels. Recently it was further pioneered by INWRDAM (Inter-Islamic Network on Water Resources Development and Management) in the treatment of greywater from sewered areas of developing countries. This technology has not been tested in un-sewered settlements of developing countries which are characterised by the lack of disposal infrastructures despite being suitable for tropical countries. This treatment system is able to produce effluent that meets the quality standard for discharge and irrigation. However, new applications of the AnUBR require further investigation in order to ascertain its feasibility and evaluate its performance in the un-sewered settlement context. Given the promising results reported for the AnUBR application for greywater treatment, this study aims to investigate the performance of the AnUBR as an alternative technology for the treatment of greywater generated in un-sewered settlements and its application in developing countries. A laboratory scale plant encompassing the AnUBR was designed, constructed and investigated using influent greywater collected from two selected case study settlements representing sewered and un-sewered areas. The plant was operated for 20 consecutives days using greywater from both selected sites separately. The influent greywater was analysed prior to feeding the plant and fed intermittently by batch as per designed feeding schedule. The performance of the AnUBR was evaluated mainly by analysing the quality of effluent produced, while the typical application was recommended based on the ability of the plant to produce effluent complying with local regulations and ability to treat greywater regardless of its source. The daily characteristics of influent greywater from both sites during the period of investigation were found to be as follows: temperature: 24 – 29ºC, pH: 7.1 – 7.2, TSS: 117.72 – 2,246.6mg/l, TN: 5.66 – 12.29mg/l, TP: 12.27 – 116.46mg/l, COD: 223.17 – 1,135.32mg/l, BOD5: 98.0 – 383.6mg/l, O&G: 52.22 – 475.29mg/l, e-coli: 8.87x104 – 2.17x107cfu/100ml, and Faecal coliform: 1.49x105 – 2.41x107cfu/100ml. The AnUBR managed to treat greywater to a quality that comply with the general standards for discharge into natural water resources. The final effluent showed a significant decrease in the level of pollutants from the initial values presented above to the following: temperature: 27 – 29 ºC, pH: 7.1 – 7.2, TSS: 5.12 – 12.82mg/l, TN 0.91 – 1.09mg/l, TP: 0.93 – 7.47mg/l, COD: 24.67 – 40.45mg/l, BOD5: 8.59 – 16.0mg/l, O&G: 1.15 – 1.72mg/l, e-coli: 213.3 – 1.12x103cfu/100ml, and Faecal coliform: 461.6 – 1.5x103cfu/100ml. Results obtained showed that the quality of influent greywater (from un-sewered settlements) is similar regardless of the water and sanitation technology. Following the operation of the AnUBR, significant removal of pollutants was observed in all processes. The overall removal efficiency averaged 80 to 95% for O&G and TSS respectively and 50 to 85% for TN and TP. The COD and BOD5 removal averaged 70 to 85% while that of micro-organisms averaged 90 to 99%. However, despite the high removal efficiency recorded the AnUBR may still require a post treatment step in order to improve the quality of effluent. It was concluded that the AnUBR is a viable alternative greywater treatment technology for un-sewered settlements, households or businesses such as hotels and restaurants. The AnUBR is able of treating high polluted greywater to effluent of quality that meets the standards for discharge or reuse provided a post treatment to ensure the complete killing of pathogenic organisms. The result of this study confirms the performance of the AnUBR for the treatment of greywater and provides an understanding of its concept as an alternative to conventional treatment and its application in un-sewered settlements based on local practical investigations.
499

Bioflocculant dissolved air flotation system for the reduction of suspended solids-lipids-Proteinaceous matter from poultry slaughterhouse wastewater

Dlangamandla, Cynthia January 2016 (has links)
Thesis (MTech (Chemical Engineering))--Cape Peninsula University of Technology, 2016. / Poultry slaughterhouse wastewater (PSW) contains organic matter that can be degraded by microorganisms. Such matter can further be used by the microbial community as a nutrient source for growth. Moreover, this type of wastewater also contains a high quantity of particulate matter, lipids and proteins, including antimicrobial compounds such as triclosan (TCS) and trichlorocarbanilide (TCC) used during cleaning and sanitising of processing facilities. Lipids and particulate matter lead to clogging of pipes and fouling of diffusers in the wastewater treatment plants (WWTPs). To overcome this problem, a pre-treatment system such as a dissolved air flotation system (DAFs) in which synthetic flocculants are used, is commonly used prior to the biological treatment of the wastewater. Synthetic flocculants add to the environmental burden associated with the use of synthetic compounds, particularly when these compounds are used in WWTPs. This study focused on the reduction of suspended solids, lipids and proteinaceous matter using a bioflocculant- supported DAF for the treatment of PSW.
500

Design, installation, and assessment of a biological winery wastewater treatment system

Holtman, Gareth Alistair January 2017 (has links)
Thesis (MTech (Civil Engineering))--Cape Peninsula University of Technology, 2017. / Currently in South Africa, most wastewater from small cellars is pH-adjusted and disposed of via land irrigation. This practice can lead to environmental degradation. There is a need for low cost, low maintenance solutions for the treatment of cellar effluent. Constructed wetlands provide such an option. However, the use of plants is problematic because winery effluent can be phytotoxic. After successful initial laboratory-scale experiments, an in-situ pilot scale biological sand filter (unplanted constructed wetland) system was designed, installed, and used to treat effluent from a small winery in the Western Cape, South Africa. The system is off-grid, totally self-regulating, and uses a modular approach which allows for the addition and subtraction of filter modules within the system to alter treatment capacity, retention time and/or rest filter modules. The system can be easily integrated into existing settling basins and/or retention ponds at small wineries. The biological sand filter was operational for 610 days, and showed promising results. The average chemical oxygen demand removal efficiency was 81% (range: 44-98%) with an average effluent of 324 mg/L, and an average flow rate of 413 L/day after the acclimation (start-up) period. The average hydraulic loading rate after the initial start-up period was 143 L/m3 sand day-1 (range: 67-222/m3 sand day-1), with an organic loading rate of 205 gCOD/m3 of sand day-1 (range: 83-338 gCOD/m3 sand day-1) which resulted in an organic removal rate of 164 gCOD/m3 of sand day-1. There was an average of 67% removal of total phenolics, thereby reducing the potential phytotoxicity of the effluent. In addition, there was a 1.6 times increase in calcium concentration, a 29% decrease in the average sodium adsorption ratio, and complete passive neutralisation of the acidic winery wastewater (final effluent pH range: 6.63 – 8.14. The findings of this study compare well with previous laboratory studies conducted with synthetic and authentic winery effluent. The system can potentially provide a low cost, energy efficient, low maintenance, sustainable means of treating cellar effluent at small wineries. Uptake of this technology may alleviate environmental degradation caused by irrigating land with inadequately treated effluent.

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