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Steroid Estrogens and Estrogenic Activity in Farm Dairy Shed EffluentsGadd, Jennifer Bronwyn January 2009 (has links)
Estrogenic contamination of waterways is of world-wide concern due to the adverse effects observed in aquatic biota. Recently, wastes from agricultural activities have been
identified as likely sources of steroid estrogens released into the environment. Wastes from dairying activities are of particular concern in New Zealand. This project included development of analytical methods to measure free and conjugated estrogens,
measurement of estrogens from the source to receiving environments and an investigation of effluent treatment technologies.
The analytical method developed in this study was based on GC-MS measurement of free estrogens (17α-estradiol (17α-E2), 17β-estradiol (17β-E2) and estrone (E1)) and LC-IT-MS measurement of their sulfate-conjugates (17α-E2-3S, 17β-3S, E1-3S) in raw and treated farm dairy shed effluents (DSE). Effluents from farms in the Canterbury and Waikato Regions, two regions where dairy farming is the dominant land-use, were collected and analysed. All effluents demonstrated high concentrations of steroid estrogens, particularly 17α-E2 (median 760 ng/L). Estrogenic activity was also elevated, at up to 500 ng/L 17β-E2 equivalents using the E-Screen, an in vitro cell proliferation bioassay. Comparison to the chemical data indicated that for most samples, the highest proportion of estrogenic activity was derived from steroid estrogens naturally excreted by dairy cows. Conjugated estrogens were measured in several raw effluent samples, at similar concentrations to those of free estrogens, particularly E1.
Dairy effluent treatment systems reduced free estrogen concentrations by 63-99% and reduced estrogenic activity by up to 89%. In spite of high removal efficiencies, estrogens remained elevated in the treated effluents that are discharged into waterways. Steroid
estrogens and estrogenic activity were detected in streams and groundwater in areas impacted by dairy farming. Although concentrations were generally low, in two streams the concentrations were above levels regarded as safe for aquatic biota (<1 ng/L). The results demonstrate that dairy effluents are indeed a major source of estrogens to the environment and to waterways.
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Phosphorus reduction in dairy effluent through flocculation and precipitationBragg, Amanda Leann 17 February 2005 (has links)
Phosphorus (P) is a pollutant in freshwater systems because it promotes eutrophication. The dairies in the North Bosque and its water body segments import more P than they export. Dairies accumulate P-rich effluent in lagoons and use the wastewater for irrigation. As more P is applied as irrigation than is removed by crops, P accumulates in the soil. During intense rainfall events, P enters the river with stormwater runoff and can become bio-available. Reducing the P applied to the land would limit P build up in the soil and reduce the potential for P pollution. Since wastewater P is associated with suspended solids (SS), the flocculants, poly-DADMAC and PAM, were used to reduce SS. To precipitate soluble P from the effluent, NH4OH was added to raise the pH. Raw effluent was collected from a dairy in Comanche County, TX, and stored in 190-L barrels in a laboratory at Texas A&M University. Flocculant additions reduced effluent P content by as much as 66%. Addition of NH4OH to the flocculated effluent raised the pH from near 8 to near 9, inducing P precipitation, further reducing the P content. The total P reduction for the best combination of treatments was 97%, a decrease from 76 to 2 mg L-1. If this level of reduction were achieved in dairy operations, P pollution from effluent application would gradually disappear.
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Phosphorus reduction in dairy effluent through flocculation and precipitationBragg, Amanda Leann 17 February 2005 (has links)
Phosphorus (P) is a pollutant in freshwater systems because it promotes eutrophication. The dairies in the North Bosque and its water body segments import more P than they export. Dairies accumulate P-rich effluent in lagoons and use the wastewater for irrigation. As more P is applied as irrigation than is removed by crops, P accumulates in the soil. During intense rainfall events, P enters the river with stormwater runoff and can become bio-available. Reducing the P applied to the land would limit P build up in the soil and reduce the potential for P pollution. Since wastewater P is associated with suspended solids (SS), the flocculants, poly-DADMAC and PAM, were used to reduce SS. To precipitate soluble P from the effluent, NH4OH was added to raise the pH. Raw effluent was collected from a dairy in Comanche County, TX, and stored in 190-L barrels in a laboratory at Texas A&M University. Flocculant additions reduced effluent P content by as much as 66%. Addition of NH4OH to the flocculated effluent raised the pH from near 8 to near 9, inducing P precipitation, further reducing the P content. The total P reduction for the best combination of treatments was 97%, a decrease from 76 to 2 mg L-1. If this level of reduction were achieved in dairy operations, P pollution from effluent application would gradually disappear.
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Steroid Estrogens and Estrogenic Activity in Farm Dairy Shed EffluentsGadd, Jennifer Bronwyn January 2009 (has links)
Estrogenic contamination of waterways is of world-wide concern due to the adverse effects observed in aquatic biota. Recently, wastes from agricultural activities have been identified as likely sources of steroid estrogens released into the environment. Wastes from dairying activities are of particular concern in New Zealand. This project included development of analytical methods to measure free and conjugated estrogens, measurement of estrogens from the source to receiving environments and an investigation of effluent treatment technologies. The analytical method developed in this study was based on GC-MS measurement of free estrogens (17α-estradiol (17α-E2), 17β-estradiol (17β-E2) and estrone (E1)) and LC-IT-MS measurement of their sulfate-conjugates (17α-E2-3S, 17β-3S, E1-3S) in raw and treated farm dairy shed effluents (DSE). Effluents from farms in the Canterbury and Waikato Regions, two regions where dairy farming is the dominant land-use, were collected and analysed. All effluents demonstrated high concentrations of steroid estrogens, particularly 17α-E2 (median 760 ng/L). Estrogenic activity was also elevated, at up to 500 ng/L 17β-E2 equivalents using the E-Screen, an in vitro cell proliferation bioassay. Comparison to the chemical data indicated that for most samples, the highest proportion of estrogenic activity was derived from steroid estrogens naturally excreted by dairy cows. Conjugated estrogens were measured in several raw effluent samples, at similar concentrations to those of free estrogens, particularly E1. Dairy effluent treatment systems reduced free estrogen concentrations by 63-99% and reduced estrogenic activity by up to 89%. In spite of high removal efficiencies, estrogens remained elevated in the treated effluents that are discharged into waterways. Steroid estrogens and estrogenic activity were detected in streams and groundwater in areas impacted by dairy farming. Although concentrations were generally low, in two streams the concentrations were above levels regarded as safe for aquatic biota (<1 ng/L). The results demonstrate that dairy effluents are indeed a major source of estrogens to the environment and to waterways.
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Techno-Economic Feasibility and Life Cycle Assessment of Dairy Effluent to Biofuel via Hydrothermal LiquefactionSummers, Hailey M. 01 May 2015 (has links)
Uncertainty in the global energy market and negative environmental impacts associated with fossil fuels has led to renewed interest in alternative fuels. The scalability of new technologies and production pathways are critically being evaluated through economic feasibility studies and environmental impact assessments. This work investigated the conversion of agricultural wast, delactosed whey permeate (delac), with yeast fermentation for the generation of biofuel via hydrothermal liquefaction (HTL). The feasibility of the process was demonstrated at laboratory scale with data leveraged to validate systems models used to perform industrial-scale economic and environmental impact analyses. Results showed a minimum fuel selling point of $4.56 per gasoline gallon equivalent (CGE), a net energy ratio (NER), defined as energy required to process biofuel divided by energy in the biofuel produced, of 0.81 and greenhouse gas (GHG) emissions of 30.03 g CO2-eq MJ-1. High Production costs can be attributed to operational temperatures of HTL while the high lipid yields of the yeast counter these heating demands, resulting in a favorable NER. The operating conditions of both fermentation and HTL contributed to the majority of GHG emissions. Further discussion focuses on optimization of the process, on the metrics of TEA and LCA and the evaluation of the process, on the metrics of TEA and LCA, and the evaluation of the process through a sensitivity analysis that highlights areas for directed research to improve commercial feasibility.
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Desempenho de unidades gotejadoras operando com diluições de efluentes de laticínios e de água de abastecimento público em escala laboratorialMarques, Blake Charles Diniz 29 February 2016 (has links)
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Previous issue date: 2016-02-29 / The problem of water crisis is directly related to factors such as increasing population,
increased demand for water, climate variations and deterioration of existing resources.
In the semi-arid Northeast the predominant characteristics of reduced rainfall, high
temperature and high evaporative rate, make the shortage of water for long periods of
the year, more and more recurrent. Liquid effluents of dairy industries have the potential
for agricultural use due to nutrient intake. However, this practice involves technical
feasibility issues inherent in the method of irrigation adopted where the clogging of the
emitters becomes more vulnerable, but can be attenuated with the technique of dilution
in water. Given the above, the study aimed to analyze the hydraulic performance
drippers units applying wastewater dilution dairy (ARL) and the public water supply
(AA). For this, it was set up a trial bench, the Pollution Laboratory and Land
Degradation (LPDS) of the Federal Rural University of Semi-Arid (UFERSA) campus
Mossoro-RN, consisting of four drippers units operating with four different dilutions of
ARL in AA (1A0E; 1A1E; 2A1E and 3A1E) and five types of drippers (G1, G2, G3, G4
and G5). The hydraulic performance of drippers units was obtained every 40 hours of
operation with dilutions of ARL AA for 200 h at 2014 20/10 10/04 2015 period, using
the indicators drip flow ( Q) flow variation coefficient (CVQ), statistical uniformity
coefficient (US), distribution uniformity coefficient (CUD) and reduction of the relative
flow rate (Dr). At the same time, they quantified the physicochemical and
microbiological attributes of ARL dilutions AA. Data were submitted to analysis of
simple and multiple regression and parametric test of Pearson correlations. Among the
physicochemical and microbiological characteristics of dairy effluent, solid values
suspended (SS), dissolved solids (DS), pH and total iron (Fe) represented drippers
clogging risk ranging from moderate to high. The SS features, SD, pH and Fe
predominated in multiple linear regression equations adjusted to the hydraulic
performance variables, combinations between types of drippers and dairy effluent
dilution levels in the public water supply. At the end of the experimental tests, samples
of emitters biofouling were subjected to photographic records and analyzes by optical
microscopy and scanning electron microscopy (SEM), showing the formation of a
biofilm on the entire internal area of the sampled emitters resulting in partial clogging
and total tested drippers, thus affecting the hydraulic system performance. Hydraulic
performance indicators Q, CUD, CVQ and Us satisfactorily expressed the drippers
obstruction levels, while Dr. underestimated the risks of obstruction brought about by
dairy effluent. The greater susceptibility to clogging occurred in the dripper G2
operating in 1A1E and 3A1E dilutions. On the other hand, the dripper G5 was less
susceptible to clogging at operating 2A1E dilution. The screen filter provided good
removal of SS with the same size or greater than 130 μm / O problema da crise hídrica está diretamente relacionado com fatores como aumento
da população, aumento da demanda por água, variações climáticas e deterioração dos
recursos existentes. No semiárido nordestino as características predominantes de índice
pluviométrico reduzido, temperatura elevada e alta taxa evaporativa, tornam a escassez
de água, por longos períodos do ano, cada vez mais recorrente. Os efluentes líquidos das
indústrias de laticínios apresentam potencial para uso agrícola, devido ao aporte de
nutrientes. No entanto, esta prática envolve questões relacionadas à viabilidade técnica,
inerente ao método de irrigação adotado, onde o entupimento dos emissores se torna a
maior vulnerabilidade, mas que pode ser atenuada com a técnica da diluição em água.
Diante do exposto, o trabalho objetivou analisar o desempenho hidráulico de unidades
gotejadoras aplicando diluições de água residuária de laticínios (ARL) e água de
abastecimento público (AA). Para isso, montou-se uma bancada experimental, no
Laboratório de Poluição e Degradação do Solo (LPDS) da Universidade Federal Rural
do Semi-Árido (UFERSA) câmpus Mossoró-RN, constituída de quatro unidades
gotejadoras operando com quatro diferentes diluições de ARL em AA (1A0E; 1A1E;
2A1E e 3A1E) e de cinco tipos de gotejadores (G1; G2; G3; G4 e G5). O desempenho
hidráulico das unidades gotejadoras foi obtido a cada 40 h de operação com as diluições
de ARL em AA, durante 200 h no período de 20/10 de 2014 a 10/04 de 2015,
utilizando-se os indicadores: vazão de gotejadores (Q), coeficiente de variação de vazão
(CVQ), coeficiente de uniformidade estatístico (Us), coeficiente de uniformidade de
distribuição (CUD) e redução da vazão relativa (Dra). Paralelamente, quantificaram os
atributos físico-químicos e microbiológicos das diluições de ARL em AA. Os dados
foram submetidos às análises de regressão simples e múltipla e teste de correlações
paramétricas de Pearson. Dentre as características físico-químicas e microbiológicas do
efluente de laticínios, os valores de sólidos suspensos (SS), sólidos dissolvidos (SD), pH
e ferro total (Fe) representaram risco de obstrução de gotejadores que variam de
moderado a alto. As características SS, SD, pH e Fe predominaram nas equações de
regressão lineares múltiplas ajustadas às variáveis de desempenho hidráulico, para as
combinações entre tipos de gotejadores e níveis de diluição do efluente de laticínios em
água de abastecimento público. Ao final dos ensaios experimentais, amostras dos
emissores com bioincrustação foram submetidas a registros fotográficos e análises por
microscopia óptica e eletrônica de varredura (MEV), evidenciando a formação de um
biofilme em toda a área interna dos emissores amostrados tendo como consequência o
entupimento parcial e total dos gotejadores testados, afetando dessa forma, o
desempenho hidráulico do sistema. Os indicadores de desempenho hidráulico Q, CUD,
CVQ e Us expressaram satisfatoriamente os níveis de obstrução de gotejadores,
enquanto o Dra subestimou os riscos de obstrução acarretado pelo efluente de laticínios.
A maior suscetibilidade ao entupimento ocorreu no gotejador G2, operando nas
diluições 1A1E e 3A1E. Por outro lado, o gotejador G5 se mostrou menos suscetível ao
entupimento operando na diluição 2A1E. O filtro de tela proporcionou boa remoção de
SS com tamanhos iguais ou superiores a 130 μm / 2016-11-17
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Água residuária de laticínio em co-digestão com dejetos de bovinos leiteiros / Dairy residual water co-digestion with dairy cattle manureFernandes, Aline [UNESP] 06 July 2016 (has links)
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Previous issue date: 2016-07-06 / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / A pecuária leiteira bem como a industrialização do leite produzem resíduos que podem impactar o meio se lançados de forma imprópria. Sendo assim, objetivou-se avaliar o efeito da co-digestão de água residuária de laticínio com dejetos bovinos em biodigestores do tipo batelada e contínuo sobre a produção de biogás e biofertilizante. O experimento foi dividido em duas fases. A primeira fase desenvolvida com biodigestores batelada e a segunda subdividida em dois períodos com biodigestores contínuos. Avaliou-se o efeito da inclusão de água residuária de laticínio (ARL) na primeira etapa: 0% de ARL, 50% de ARL, 77,5% de ARL, 100% de ARL e tratamento ARL. Para segunda fase no primeiro período tratamento com 0% de ARL e 50% de ARL. E no segundo período com tratamentos de 0% ARL e 63,5% ARL. Para análise dos dados considerou-se um delineamento inteiramente casualizado, utilizando-se o programa SAS® com nível de significância de 5%. Para a primeira fase, observou–se que o tratamento ARL foi o que apresentou menor produção de biogás (0,00753 m3) em relação aos demais. Para os potenciais de produção o tratamento com 50% de ARL apresentou as menores médias. Nos dois períodos da segunda fase, ou seja, com biodigestores contínuos, os resultados demonstram que os tratamentos contendo água residuária foram eficientes sem diferença de produção de biogás entre os tratamentos. O aproveitamento da água residuária para compor substrato em co-digestão com dejetos bovinos leiteiros apresentou condições favoráveis de produção e qualidade de biogás e biofertilizante. / The dairy farming and industrialization of milk produce waste that may impact the environment if disposed improperly. Thus, this study aimed to evaluate the effect of co-digestion of dairy production wastewater with cattle manure in biodigesters in the batch and continuous type on the production of biogas and biofertilizers. The experiment was divided into two phases. The first phase developed with batch digesters and second divided in two periods with continuous digesters. We evaluated the effect of the inclusion of dairy wastewater (DW) in the first stage: 0% of DW, 50% of DW, 77,5% of DW, 100% of DW and DW treatment. For the second phase the first treatment period with 0% and 50% DW. And in the second period with treatments of 0% and 63.5% DW. Data analysis was considered a completely randomized design, using the SAS® program with 5% significance level. For the first phase, it was observed that the DW treatment showed the lower production of biogas (0.00753 m3) compared to the others treatments. For the production potential treatment with 50% of DW had the lowest means. In the second phase in both periods, with continuous digesters, the results show that the treatments containing wastewater were effective and there is no difference in biogas production between the treatments. The use of wastewater to form substrate co-digestion of dairy cattle manure showed favorable production conditions and quality of biogas and biofertilizers.
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Aplicação de processo oxidativo avançado (POA) como pré-tratamento de efluente de laticínio para posterior tratamento biológico / Aplication of Advanced Oxidative Process (AOP) as pretreatment of dairy wastewater for subsequent biologic treatmentSalazar, Rodrigo Fernando dos Santos 09 March 2009 (has links)
O foco deste trabalho foi desenvolver um sistema de tratamento híbrido, constituído por um pré-tratamento fotocatalítico heterogêneo (POA) e posterior tratamento biológico por lodo ativado (SLA), para a redução da carga orgânica de efluentes laticinista oriundos do processamento de lácteos líquidos, como por exemplos, cremes, iogurte e beneficiamento de leite. Para a caracterização analítica do efluente in natura e tratado empregaram-se as metodologias Standard Methods, validadas em função do tipo e da complexidade da amostra (DQO, DBO, Norgânico, N-NH4 +, PTotal, Fe2+, O&G, ST, STF, STV, SS, SD, Al, As, Ca, Fe, Mge Pb). Através de planejamentos fatoriais determinaram-se as melhores condições entre as variáveis estudadas para as etapas de tratamentos com POA e lodo ativado, tendo como fator de resposta a redução da DQO. Para a etapa de POA empregou-se a fotocatálise, utilizando como semicondutor o dióxido de titânio (TiO2) finamente distribuído e fixado com tinta poliuretânica sobre uma chapa metálica plana, onde o efluente foi percolado sobre o respectivo leito catalítico posicionado em um ângulo fixo de 23º, recebendo a radiação solar direta. O dois tipos de estrutura de TiO2 (rutilo ou anatase) foram avaliados morfologicamente (DRX, BET, MEV-EDS) e cineticamente, como uma variável do processo fotocatalítico: a fase anatase apresentou maior eficiência de degradação da matéria orgânica, em pH 5. Posteriormente à degradação da carga orgânica por reação fotoquímica, as amostras foram tratadas biologicamente por lodo ativado e, conseqüentemente, pode-se analisar e otimizar um sistema híbrido (POA - SLA) que apresentasse maior eficiência de degradação da matéria orgânica do efluente lácteo utilizado. Ensaios de biodegradação sem o pré-tratamento com POA apresentou uma redução de 26,01 ± 5,23 % em 72 h de tratamento. O sistema (POA - SLA) que apresentou maior eficiência de degradação da matéria orgânica, em 72 h de tratamento, foi de 93,70 ± 0,10 % caracterizado por uma DQO de entrada em 3782,5 ± 37,6 mg O2 L-1 e uma DQO de saída (efluente tratado) em 236,8 ± 0,1 mg O2 L-1. / The aim of this work is at developing a hybrid system in order to treat dairy wastewater. The hybrid system was composed by two modules. The first one is based in advanced oxidative process (AOP) and the second in actived sludge system (SLA). Methodologies from Standard Methods were adaptded and validated (BOD, COD, Norganic, N - NH4 +, Ptotal, Fe2+, G&O, TS, TFS, VSS, TSS, TDS, Al, As, Ca, Fe, Mg and Pb) for dairy effluent characterization. The best conditions for AOP and SLA processes had been determined through Designs of Experiments (DOE). The efficiency of both processes was avaliabled by COD. AOP treatment based on photocatalisis was applied. Titanium dioxide (TiO2) was used as semiconductor. This TiO2 was finely distributed and settled with poliuretanic ink on a plain metallic plate where the effluent was circulated on the respective located catalytic stream bed in fixed angle of 23º. This process (AOP) received direct solar radiation. Two types of crystalline structure of TiO2 (rutile or anatase) had been evaluated morphologically (XRD, BET, SEM-EDS) and kinetically, as an variable of photocatalisis process: the anatase crystalline phase in pH 5 have shown better degradation of dairy wastewater. The samples had been treated by SLA later photochemical reaction. The hybrid system (AOP - SLA) was then analyzed and optimized. 72 hours of biodegradation tests without AOP pretreatment had been shown 26,01 ± 5,23 % of COD reduction. Over optimized conditions the hybrid system showed 93,70 ± 0,10 % of COD reduction with a initial organic load of 3782,5 ± 37,6 mg O2 L-1 and final COD of 236,8 ± 0,1 mg O2 L-1 (treated effluent).
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Aplicação de processo oxidativo avançado (POA) como pré-tratamento de efluente de laticínio para posterior tratamento biológico / Aplication of Advanced Oxidative Process (AOP) as pretreatment of dairy wastewater for subsequent biologic treatmentRodrigo Fernando dos Santos Salazar 09 March 2009 (has links)
O foco deste trabalho foi desenvolver um sistema de tratamento híbrido, constituído por um pré-tratamento fotocatalítico heterogêneo (POA) e posterior tratamento biológico por lodo ativado (SLA), para a redução da carga orgânica de efluentes laticinista oriundos do processamento de lácteos líquidos, como por exemplos, cremes, iogurte e beneficiamento de leite. Para a caracterização analítica do efluente in natura e tratado empregaram-se as metodologias Standard Methods, validadas em função do tipo e da complexidade da amostra (DQO, DBO, Norgânico, N-NH4 +, PTotal, Fe2+, O&G, ST, STF, STV, SS, SD, Al, As, Ca, Fe, Mge Pb). Através de planejamentos fatoriais determinaram-se as melhores condições entre as variáveis estudadas para as etapas de tratamentos com POA e lodo ativado, tendo como fator de resposta a redução da DQO. Para a etapa de POA empregou-se a fotocatálise, utilizando como semicondutor o dióxido de titânio (TiO2) finamente distribuído e fixado com tinta poliuretânica sobre uma chapa metálica plana, onde o efluente foi percolado sobre o respectivo leito catalítico posicionado em um ângulo fixo de 23º, recebendo a radiação solar direta. O dois tipos de estrutura de TiO2 (rutilo ou anatase) foram avaliados morfologicamente (DRX, BET, MEV-EDS) e cineticamente, como uma variável do processo fotocatalítico: a fase anatase apresentou maior eficiência de degradação da matéria orgânica, em pH 5. Posteriormente à degradação da carga orgânica por reação fotoquímica, as amostras foram tratadas biologicamente por lodo ativado e, conseqüentemente, pode-se analisar e otimizar um sistema híbrido (POA - SLA) que apresentasse maior eficiência de degradação da matéria orgânica do efluente lácteo utilizado. Ensaios de biodegradação sem o pré-tratamento com POA apresentou uma redução de 26,01 ± 5,23 % em 72 h de tratamento. O sistema (POA - SLA) que apresentou maior eficiência de degradação da matéria orgânica, em 72 h de tratamento, foi de 93,70 ± 0,10 % caracterizado por uma DQO de entrada em 3782,5 ± 37,6 mg O2 L-1 e uma DQO de saída (efluente tratado) em 236,8 ± 0,1 mg O2 L-1. / The aim of this work is at developing a hybrid system in order to treat dairy wastewater. The hybrid system was composed by two modules. The first one is based in advanced oxidative process (AOP) and the second in actived sludge system (SLA). Methodologies from Standard Methods were adaptded and validated (BOD, COD, Norganic, N - NH4 +, Ptotal, Fe2+, G&O, TS, TFS, VSS, TSS, TDS, Al, As, Ca, Fe, Mg and Pb) for dairy effluent characterization. The best conditions for AOP and SLA processes had been determined through Designs of Experiments (DOE). The efficiency of both processes was avaliabled by COD. AOP treatment based on photocatalisis was applied. Titanium dioxide (TiO2) was used as semiconductor. This TiO2 was finely distributed and settled with poliuretanic ink on a plain metallic plate where the effluent was circulated on the respective located catalytic stream bed in fixed angle of 23º. This process (AOP) received direct solar radiation. Two types of crystalline structure of TiO2 (rutile or anatase) had been evaluated morphologically (XRD, BET, SEM-EDS) and kinetically, as an variable of photocatalisis process: the anatase crystalline phase in pH 5 have shown better degradation of dairy wastewater. The samples had been treated by SLA later photochemical reaction. The hybrid system (AOP - SLA) was then analyzed and optimized. 72 hours of biodegradation tests without AOP pretreatment had been shown 26,01 ± 5,23 % of COD reduction. Over optimized conditions the hybrid system showed 93,70 ± 0,10 % of COD reduction with a initial organic load of 3782,5 ± 37,6 mg O2 L-1 and final COD of 236,8 ± 0,1 mg O2 L-1 (treated effluent).
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Ozonização catalítica de efluente de laticínio em processo semi-batelada com reciclo / Catalytic ozonation of dairy effluent in semi-batch process with recycleMessias, Raquel de Aquino 20 July 2015 (has links)
O efluente lácteo é caracterizado pelo elevado teor de matéria orgânica. Os principais impactos ambientais causados pelas indústrias de laticínios estão relacionados ao lançamento dos efluentes líquidos, geralmente com ineficiente controle ou tratamento, sendo de fundamental importância a implementação de técnicas de tratamento eficazes e de baixo custo. Dentro desta proposta, os chamados Processos Oxidativos Avançados (POAs) são tecnologias eficientes para a oxidação (parcial ou total) de compostos orgânicos de difícil degradação. O presente trabalho de pesquisa objetivou a avaliação da potencialidade da ozonização catalítica, para a redução da carga orgânica do efluente proveniente da indústria de laticínio Cia de Alimentos Glória da cidade de Guaratinguetá, oriundos do processamento de beneficiamento de leite, utilizando-se Fe2+ como catalisador em processo semi-batelada com reciclo. A caracterização do efluente lácteo in natura foi realizada empregando-se métodos estabelecidos e otimizados de alguns parâmetros elencados nas legislações ambientais, destacando-se: DQO, COT, DBO5, Nitrogênio (orgânico e amoniacal), Fósforo total, Ferro, Sólidos (ST, STF, STV), surfactantes aniônicos, óleos e graxas e elementos metálicos. Através de planejamento fatorial fracionado 24-1, determinaram-se as melhores condições entre as variáveis potência do ozonizador, vazão de O2, concentração de Fe2+ e pH para a etapa de tratamento com POA, tendo como fator de resposta a redução da DQO e COT. Avaliou-se também uma nova configuração de reator em função de uma espuma formada durante o processo de tratamento. Os resultados obtidos para o conjunto de experimentos mostraram-se promissores, sendo que a redução média de COT com 63,95 % e de DQO com 70,50 % para o ensaio com as variáveis da reação otimizada, com o custo no valor de R$ 0,056 / L de efluente. Após o processo de ozonização catalítica, a amostra do melhor experimento: pH 4,0, concentração de Fe2+ 1,0 g L-1, potência 86 W, vazão de O2 0,5 L min-1, tendo como vazão mássica de O3 3,10 mg min-1, foi tratada por um processo biológico - Sistema Lodo Ativado (SLA), a fim de verificar a eficiência de degradação da matéria orgânica do efluente estudado através do sistema conjugado (POA - SLA). Os resultados para o tratamento híbrido apresentou percentuais de reduções para COT de 82,95 %, DQO de 95,60 % e DBO de 93,09 %. / Dairy effluent is characterized by the high content of organic material. The major environmental impacts caused by dairy industries are related to the release of liquid effluents, generally with an inefficient control or treatment, which makes it essential to implement effective treatment techniques, at a low cost. Within this proposal, Advanced Oxidation Processes (AOPs) are efficient technologies for oxidation (partial or total) of organic compounds of difficult degradation. This research study aimed at assessing the potential of catalytic ozonation for reduction of the effluent organic load from the dairy industry Cia de Alimentos Glória located in the city of Guaratinguetá, State of São Paulo, Brazil, derived from milk processing, using Fe2+ as catalyst in a semi-batch process with recycle. The characterization of milky effluent in natura was performed by using established and optimized methods of some parameters listed in environmental legislation, among them: COD, TOC, BOD5, Nitrogen (organic and ammoniacal), total Phosphorus, Iron, Solids (TS, FTS, VTS), anionic surfactants, oils and greases and metallic elements. Through fractional factorial design 24-1, the best conditions among the power variables of the power ozonator, O2 flow, Fe2+ concentration and pH were determined for the treatment stage with AOP, with a response factor of COD and TOC reduction. A new configuration of reactor was also assessed due to the presence of foam during the treatment process. The obtained results for the set of experiments were found to be promising, with an average reduction of TOC of 63.95 % and of 70.50 % for COD for the test with optimized reaction variables, with a cost of U$$ 0.02 / L of effluent. After the catalytic ozonation process, the sample of the best experiment was: pH 4.0, concentration of Fe2+ 1.0 g L-1, power of 86 W, flow of O2 0.5 L min-1, with mass flow of O3 3.10 mg min-1, was treated by a biological process in order to verify to verify the efficiency of degradation of the organic matter of the effluent studied through the conjugated (AOP - AS) system.The results for the hybrid treatment showed percentages of reductions for TOC of 82.95 %, COD of 95.60 % and BOD5 of 93.09 %.
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