Recent advances in the structure and function of microbial community in anaerobic granular sludge / 生物工程学报

Anaerobic granular sludge (AnGS), a self-immobilized aggregate containing various functional microorganisms, is considered as a promising green process for wastewater treatment. AnGS has the advantages of high volume loading rate, simple process and low excess sludge generation, thus shows great technological and economical potentials. This review systematically summarizes the recent advances of the microbial community structure and function of anaerobic granular sludge, and discusses the factors affecting the formation and stability of anaerobic granular sludge from the perspective of microbiology. Moreover, future research directions of AnGS are prospected. This review is expected to facilitate the research and engineering application of AnGS.

Avaliação do perfil de resistência aos antimicrobianos em cepas de Escherichia coli e Staphylococcus spp. no canal do Marambaia em Balneário Camboriú, Santa Catarina / Evaluation of the antimicrobial resistance profile of isolated strains of Escherichia coli and Staphylococcus spp. in the Marambaia river in Balneário Camboriú, Santa Catarina

Introdução: Durante as últimas décadas, diversos micropoluentes orgânicos foram liberados no meio ambiente como resultado de atividades antropogênicas. Entre eles, se destacam os antibióticos, substâncias pouco biodegradáveis e muito persistentes que, ao se  acumularem nos sistemas aquáticos, proporcionam um ambiente favorável à seleção e proliferação de microrganismos resistentes a antimicrobianos. Objetivo: Avaliar o perfil de resistência aos antimicrobianos em cepas de Escherichia coli e Staphylococcus spp., isoladas no rio Marambaia e na praia adjacente, em Balneário Camboriú, Santa Catarina. Método: A amostragem foi dividida em seis coletas, totalizando 36 amostras e abrangendo todas as estações do ano. Foram realizadas análises microbiológicas fenotípicas, incluindo morfologia e testes de susceptibilidade aos antimicrobianos. A análise de dados foi realizada com o auxílio dos softwares Excel e Past, versão 4.03, através de análise explorativa e descritiva. Resultados: Foi verificada a presença de coliformes totais e termotolerantes, em todos os pontos amostrais, indicando a influência da desembocadura do rio na praia, além disso, a concentração de E. coli encontrada nos pontos amostrais está em desacordo com a Resolução Conama n° 357/2005, exceto para os pontos Marambaia 1 e Praia 3. De forma geral, cinco cepas apresentaram resistência a pelo menos três antibióticos, sendo a mais expressiva a ampicilina, com 14 cepas resistentes. O índice MAR para Staphylococcus spp. mostrou altos riscos para multirresistência, não apresentando diferenças para os fatores momento e local de coleta, sendo que 96 cepas apresentaram resistência para pelo menos um antibiótico. Foi encontrado um  número maior de cepas resistentes aos antimicrobianos eritromicina e clindamicina. Conclusões: A presença de E. coli é preocupante por se tratar de um coliforme termotolerante, indicativo de contaminação fecal recente. A existência de mecanismos de resistência nessas bactérias pode modificar a microbiota local, colocando em risco a saúde da população. Quanto aos Staphylococcus spp., através da avaliação dos dados do índice MAR, verificou-se riscos altos de multirresistência para a maioria dos locais amostrados e em qualquer momento das coletas. Além disso, poucas cepas foram sensíveis para todos os antibióticos testados. A análise do antibiograma revelou que 96 cepas apresentaram resistência para pelo menos uma classe de antimicrobiano. Os mecanismos de resistência que ocorrem em Gram-positivos, apesar de divergirem daqueles ocorridos em Gram-negativos, são igualmente preocupantes, seja do ponto de vista  icrobiológico ou em questões de saúde pública.

Introduction: During the last few decades, various organic micropollutants, including antibiotics, have been released into the environment because of anthropogenic activities. These drugs are poorly biodegradable and very persistent, such that when they accumulate in aquatic systems, they provide a favorable environment for the selection and proliferation of resistant microorganisms. Objective: Evaluate the antimicrobial resistance profile of isolated strains of Escherichia coli and Staphylococcus spp taken from the Marambaia river and its adjacent beach, in Balneário Camboriú, in the Brazilian state of Santa Catarina. Method: The sampling was divided into six collections, with a total of thirty-six samples, across all seasons of the year.  Subsequently, microbiological analyses and antibiotic sensitivity tests were performed. Data analysis was performed using the software programs Excel and Past, version 4.03, through exploratory and descriptive analyses. Results: The results showed the presence of total and thermotolerant coliforms at all sampling points, indicating the influence of the river outflow on the beach. Moreover, the concentrations of E. coli found in the sampling points are not compliant with Conama Resolution 357/2005,  except for the points Marambaia 1 and Praia 3. The MAR index for Staphylococcus showed high risks for multidrug resistance, with no differences for the time and place of collection. Ninety-six strains were resistant to at least one antibiotic. The isolated strains showed greater resistance to antibiotics erythromycin and clindamycin. Conclusions: The presence of E. coli is worrisome because it is a thermotolerant coliform, indicative of recent fecal contamination. The presence of resistance mechanisms in these bacteria can modify the local microbiota, putting the health of the population at risk. As for Staphylococcus spp., through the evaluation of the MAR index, high risks of multidrug resistance were found for most of the sampled locations and at any time of collection. In addition, few strains were sensitive to all antibiotics tested. The resistance mechanisms that occur in Gram-positives, despite differing from those that occur in Gram-negatives, are equally worrisome, whether from a microbiological point of view or in terms of public health.

Role of nanomaterials in catalytic reduction of organic pollutants

Developing innovative technologies for the effective treatment of wastewater containing organic pollutants is of extreme importance across the globe. The organic pollutants such as dyes and nitrophenols are the common hazardous pollutants known for their adverse effects on humans and aquatic organisms. Various methods have been used for the removal of organic pollutants from wastewater but they suffer limitations such as high cost, time consuming removal process and production of sludge or toxic by-products. In recent years, chemical reduction method is becoming popular for removal of organic pollutants using various nanomaterials as catalysts. Nanomaterials show great potential for removal of organic pollutants due to large surface area which provides high catalytic activity. In the present review, current studies on catalytic reduction of organic pollutants (dyes and nitrophenols) using four different types of nanomaterials specifically carbon nanotubes, silica, metal oxide and chitosan polymer based have been explored. The factors affecting the catalytic process and mechanism of catalysis is explained in detail.In addition, a critical discussion about the pros and cons of each nano-catalyst have also been included for developing better understanding of the choice of catalyst.

Exploring integrated methodology for phytoremediation and biofuel production potential of Eichhornia crassipes

Eichhornia crassipes (EC) is a well-known invasive weed in different aquatic ecosystems. Its effective and complete eradication remains a challenge. The plant is a heavy metal (HM) hyperaccumulator in water bodies; however, studies regarding its biomass utilisation post-phytoremediation remain limited. The abundant growth rate and biochemical composition make EC a promising lignocellulosic feedstock for biofuel production; hence could be a deterministic approach for solving the twin problems of water pollution and higher energy demand, which are the global pressing issues in today’s scenario. The present study aimed at evaluating the phytoremediation potential of EC followed by proximate and biochemical analysis to investigate its suitability for biofuel production. After two weeks, the EC removed above 90% of Lead (Pb) and 60% of Cadmium (Cd) at all experimental doses. Lower doses of HMs, especially Pb, showed stimulatory effects on E. crassipes leaf biomass (ECLB). The recovered ECLB from Pb contaminated water (1 mg L?1) was further analysed for moisture (89.23±0.86%), dry matter (10.77±0.60%), ash (11.91±1.20%), organic carbon (51.56±1.08%), cellulose (21.89±0.64%), hemicellulose (26.50±1.13%), lignin (5.62±0.83%), total carbohydrate (32.00±1.58%), and protein (20.83±0.52%) content. SEM imaging of harvested ECLB confirmed compact and rigid structure. The recorded peaks in FTIR-spectra (1015.21, 1153.71, 1246.01, 1339.63, 1419.71, 1540.71, 1646.80, 1736.73, 2933.03, and 3263.72 cm?1) indicate the presence of lignocellulosic biomass. XRD peak at 21.55? confirmed the crystalline fraction of cellulose in ECLB. The results of theoretical yields of H2 and CH4 co-generation (HMG) (210.85 mLH2/g DW and 150.28 mL CH4/g DW) and Bioethanol (0.278 g/g DW) derived from cellulose and hemicellulose content of ECLB were comparable to those in reported studies. Overall, this work demonstrates an integrated methodology of phytoremediation followed by biofuel production from the recovered phytobiomass.

Research progress of combined anaerobic ammonium oxidation (ANAMMOX) process for nitrogen removal / 生物工程学报

Anaerobic ammonia oxidation (ANAMMOX) process is an efficient and low-cost biological nitrogen removal process. However, it still faces some challenges in mainstream applications due to the limitation of substrate types and nitrate accumulation. In recent years, the combined process of anammox has been widely studied to solve the above problems. In this paper, the combined processes of anammox developed in recent years are reviewed, and discussed from the process principle, advantages and disadvantages, influencing factors, process extensibility and the key bottlenecks existing in the promotion and application, as well as the relevant work of the subject group. Finally, we take an outlook on the development of the combined anaerobic ammonia oxidation process in municipal domestic wastewater treatment.

Avaliação de ultrafiltração como alternativa à flotação por ar dissolvido no pós-tratamento do efluente de lodos ativados — estudo em escala piloto na estação de tratamento de esgoto Brasília norte / Evaluation of ultrafiltration as an alternative to dissolved air flotation for the post-treatment of activated sludge effluent — pilot study in the Brasília norte wastewater treatment plant

RESUMO A melhoria da qualidade dos efluentes das estações de tratamento de esgotos Brasília Norte e Sul tornou-se premente após o corpo receptor dos seus efluentes, o lago Paranoá, passar a ser utilizado como manancial de abastecimento. Este trabalho apresenta estudo comparativo entre o tratamento terciário por ultrafiltração precedido por coagulação em escala piloto e a flotação por ar dissolvido existente na estação de tratamento de esgotos Brasília Norte. A instalação piloto de ultrafiltração e a flotação por ar dissolvido foram alimentadas pela mesma matriz, o efluente da etapa de lodos ativados das estações de tratamento de esgotos Brasília Norte, após coagulação. Foram avaliadas sete condições operacionais da instalação piloto de ultrafiltração variando-se a vazão, o tempo de operação entre limpezas e a duração da limpeza física. O comportamento operacional e a qualidade do efluente produzido foram monitorados. O aumento do fluxo do permeado (de 40,2 para 50,6 e 61,0 L.m−2.h−1) e do tempo de operação entre as limpezas (de 25 para 38 e 50 min), bem como a redução da duração da retrolavagem (de 80 para 60 e 30 s) resultaram em evolução mais intensa da pressão transmembrana. A ultrafiltração foi mais eficiente do que a flotação por ar dissolvido na remoção de turbidez, sólidos suspensos totais, demanda química de oxigênio e fósforo total, com ganho médio de remoção de 9,4, 13,0, 8,5 e 12,8%, respectivamente. Destaca-se a remoção de coliformes na ultrafiltração, 3,4 log superior à da flotação por ar dissolvido. A utilização da ultrafiltração como alternativa à flotação por ar dissolvido apresenta a vantagem de produzir efluente de melhor qualidade, particularmente no aspecto microbiológico, com menor flutuação da qualidade, porém o tratamento e a destinação do lodo produzido pela ultrafiltração devem ser equacionados.

ABSTRACT Improvement in the effluent quality of the Brasília Norte and Brasília Sul wastewater treatment plants became necessary after their effluent receiving body, Paranoá Lake, started being used as source of drinking water for the population of Brasília (Federal District, Brazil). This is a comparative study between the tertiary treatment with ultrafiltration membrane (pilot scale) and the existing dissolved air flotation of Brasília Norte wastewater treatment plant. Both ultrafiltration pilot plant and dissolved air flotation were fed with the same matrix, the effluent of the activated sludge stage of Brasília Norte wastewater treatment plants, after coagulation. Seven operational conditions were evaluated at ultrafiltration pilot plant, with variations in flow rate, time of operation between cleaning processes, and the duration of backwashing. The operational behavior and the quality of the produced effluent were monitored. The increase in permeate flux (from 40.2 to 50.6 and 61.0 L.m−2.h−1) and in the time of operation between cleaning processes (from 25 to 38 and 50 min), as well as the reduction of backwashing duration (from 80 to 60 and 30s), resulted in a more intense evolution of transmembrane pressure. Ultrafiltration was more efficient than dissolved air flotation in the removal of turbidity, total suspended solids, chemical oxygen demand, and total phosphorous, with average gain in removal of 9.4, 13.0, 8.5, and 12.8%, respectively. It is worth mentioning the removal of coliforms by ultrafiltration, which was, on average, 3.4 log higher than that by dissolved air flotation. The use of ultrafiltration as an alternative to dissolved air flotation has the advantage of producing better quality effluent, particularly regarding microbiological aspects, providing lower quality fluctuation; however, treatment and destination of the ultrafiltration waste must be considered.

Custos de operação e manutenção de estação de tratamento de esgotos por reator anaeróbio e lodos ativados / Operating and maintenance costs of wastewater treatment plant by anaerobic reactor and activated sludge

RESUMO Este trabalho apresentou estudos de custos de operação e manutenção (O&M) na estação de tratamento de esgotos (ETE) de nível terciário, intitulada ETE do Baldo, localizada na cidade de Natal, Rio Grande do Norte. Teve como objetivo avaliar a eficiência econômico-ambiental da ETE através da determinação de indicador de desempenho, calculado via identificação e quantificação de todos os custos operacionais e de manutenção envolvidos nos seus processos internos de tratamento. Na pesquisa, foram identificados os diversos componentes dos custos de O&M responsáveis pelas atividades necessárias ao funcionamento da ETE de julho de 2016 a dezembro de 2018, reunidos em quatro grupos de custos. Os custos mensais foram correlacionados com os dados de vazões do período, e os de O&M por metro cúbico de esgoto tratado ao longo dos anos de 2016, 2017 e 2018 assumiram valores médios de R$ 0,32, R$ 0,30 e R$ 0,38·m−3, respectivamente. Os custos referentes ao pessoal e ao consumo energético exerceram, em todos os meses analisados, o primeiro e o segundo componentes de maior representatividade no custo total, assumindo as seguintes composições percentuais: 56,72 e 26,75% no segundo semestre do ano de 2016; 46,69 e 28,73% no ano de 2017; e 52,44 e 27,56% no ano 2018. Por fim, recomendam-se estudos na implementação de melhorias nos grupos pessoal e energia, tendo em vista que são responsáveis por cerca de 75% de todos os custos de O&M da ETE.

ABSTRACT This study presented operational and maintenance costs (O&M) at the tertiary wastewater treatment plant (WWTP) entitled Baldo's ETE, located in the city of Natal, Rio Grande do Norte. Its aim was to evaluate the economic and environmental efficiency of the WWTP through the determination of a performance indicator, calculated from the identification and quantification of all the operational and maintenance costs involved in its internal processes of treatment. The research identified the various components of O&M costs responsible for the activities necessary for the operation of the WWTP from July 2016 to December 2018, assembled into 4 cost groups. The monthly costs were correlated with the flow data of the period. O&M costs per cubic meter of sewage treated over the years 2016, 2017, and 2018 assumed average values of R$ 0.32, R$ 0.30, and R$ 0.38·m−3, respectively. Personnel and energy consumption costs accounted for the first and second most representative components of the total cost in all the months analyzed, with the following percentage compositions: 56.72 and 26.75% in the second half of 2016; 46.69 and 28.73% in 2017; and 52.44 and 27.56% in the year 2018. Finally, studies on the implementation of improvements in the personal and energy groups are recommended, as they account for about 75% of all O&M costs of the WWTP.

SARS-CoV-2 en aguas residuales y superficiales: ¿cómo lidiar con el problema? / Sars-cov-2 in wastewater and surface water: how to deal with the problem?

Introducción: hoy la humanidad sufre uno de los peores episodios debido a la pandemia causada por el SARS-CoV-2. Su alta infectividad, rápida propagación y persistencia en ciertas superficies dificultan el combate de este virus. Su presencia en aguas residuales y posible transmisión fecal-oral podría ser una nueva amenaza para la salud pública. Objetivo: alertar a la comunidad científica internacional y a los gobiernos sobre la presencia de SARS-CoV-2 en las aguas residuales y sobre qué hacer para evitar su propagación por este medio. Métodos: se realizó una revisión de artículos referenciados en SCOPUS y Web of Science desde el año 2019 relacionados con la presencia del virus en aguas residuales y superficiales. Resultados y discusión: es necesario establecer sistemas de monitoreo, utilizar métodos analíticos sensibles y rápidos para la detección del virus en las aguas residuales y superficiales. Asimismo, implantar protocolos de inactivación del virus en las unidades de salud y en las plantas de tratamiento de aguas. Se recomiendan procesos con oxidantes químicos, radiación ultravioleta, fotocatálisis, foto-Fenton, ozono o filtración por membrana. Además, se debe alertar a la población sobre la importancia del lavado y de la desinfección de productos agrícolas, así como del cuidado en su manejo por parte de los trabajadores agrícolas

Introduction: Today, humanity suffers one of the worst episodes due to a pandemic caused by the SARS-CoV-2. Its high infectivity and rapid spread combined with its persistence on certain surfaces difficult to fight this virus. Its presence in wastewater and possible fecal-oral transmission could be a new public health threat. Objective: To alert the international scientific community and governments about the presence of SARS-CoV-2 in wastewater, and what to do to prevent its spread by this means. Methods: A review of articles referenced in SCOPUS and Web of Science since 2019 related to the presence of the virus in wastewater and surface water was performed. Results and discussion: It is necessary to establish monitoring systems with the use of sensitive and rapid analytical methods for the on-site detection of viruses in wastewaters and surface waters. It should be established virus inactivation protocols at the health units, and water treatment plants, where are recommended processes with chemical oxidants, ultraviolet radiation, photocatalysis, photo-Fenton, ozone, or membrane filtration. It is necessary to alert the population about the importance of washing and disinfecting agricultural products, mainly vegetables and fruits, as well as the care in its handling by agricultural workers

Evaluación del potencial de Desmodesmus asymmetricus y Chlorella vulgaris para la remoción de nitratos y fosfatos de aguas residuales / Potential assessment of Desmodesmus asymmetricus and Chlorella vulgaris for removal of nitrates and phosphates in wastewater

Resumen En este estudio evaluamos las microalgas Chlorella vulgaris y Demodesmus asymmetricus, con el fin de determinar la proporción de microalgas que remueven la mayor concentración de nitrógeno y fósforo en aguas residuales de una planta de tratamiento. Se realizó un diseño de mezclas de las microalgas con el agua residual durante 9 días, con fotoperiodo 12:12 h, en un invernadero. Las mayores eficiencias de remoción de nitrógeno (principalmente NO3 -N y NO2 -N) y fósforo (PO4 ) se observaron en los tratamientos con mayor proporción de D. asymmetricus, entre ellos sobresalió el tratamiento T3 (25% C. vulgaris / 75% D. asymmetricus) donde se removió el 100% de nitrógeno y 77.1% de fósforo. De igual manera con el oxígeno disuelto (OD), el T3 obtuvo el mejor resultado alcanzando una media de 25.50 ± 0.28 mg/L. Finalmente, de acuerdo con el análisis del diseño de mezclas, se determinó que la mezcla óptima de microalgas que logra la mayor producción de OD y la mayor remoción, fue la proporción de 6% de C. vulgaris y 94% de D. asymmetricus en un tiempo de cultivo de 9 días. En conclusión, las microalgas demuestran su capacidad de biorremediación de aguas residuales domésticas.

Abstract In this work, we evaluated the proportion Chlorella vulgaris and Demodesmus asymmetricus microalgae, that removes the highest concentration of nitrogen and phosphorus in wastewater from a treatment plant. A mixture design was employed in this study, for 9 days, with 12:12 h photoperiod, in a greenhouse. The highest nitrogen removal efficiencies (mainly NO3 -N and NO2 -N) and phosphorus (PO4 ) were observed in treatments with the highest proportion of D. asymmetricus, including T3 (25% C. vulgaris / 75 % D. asymmetricus), where 100.0% nitrogen and 77.1% phosphorus were removed. Likewise, T3 obtained the best result of dissolved oxygen (DO), achieving average of 25.50 ± 0.28 mg/L. Finally, according to the analysis of the mixture design, the optimal microalgae mixture was determinated that achieves the highest DO production, and the highest removal was the proportion of 6% of C. vulgaris and 94% of D. asymmetricus in 9 days cultivation time. In conclusion, microalgae have shown their capacity for bioremediation of domestic wastewater, which is an alternative to consider.

Tecnologia de lodo granular aeróbio no tratamento de esgoto doméstico: oportunidades e desafios / Aerobic granular sludge technology in domestic wastewater treatment: opportunities and challenges

RESUMO Considerado por muitos profissionais como um dos maiores avanços do século 21 na área de tratamento de esgotos, os reatores de lodo granular aeróbio (LGA) vêm recebendo bastante atenção em termos de pesquisa e instalação em escala plena em diferentes continentes e condições climáticas. São frequentes os relatos na literatura de eficiências de remoção acima de 90% em termos de demanda química de oxigênio, nitrogênio total e fósforo total, além da manutenção no reator de elevadas concentrações de sólidos (> 8 g SSV/L) sem a necessidade de decantador secundário e recirculação de lodo. Contudo, há também diversos relatos de problemas de instabilidade da biomassa, longo período de formação dos grânulos (principalmente quando se utiliza esgoto real), formação de grânulos pequenos, acúmulo de nitrito e outras questões. Esta revisão explora os mecanismos necessários para granulação em estações de tratamento de esgoto em escala plena no tratamento de esgoto sanitário, incluindo os principais grupos microbianos presentes no LGA, parâmetros-chave para a formação dos grânulos, configurações de reator etc. Além disso, discutem-se algumas questões sobre a operação e a manutenção desses sistemas em escala plena.

ABSTRACT Considered by many professionals as one of the greatest advances in wastewater treatment in the 21st century, the aerobic granular sludge (AGS) reactors have received great attention in terms of research and full-scale installation in different continents and weather conditions. There are frequent reports in the literature on removal efficiencies above 90% in terms of COD, total nitrogen and total phosphorus, as well as the maintenance of high solids concentrations (> 8 g VSS/L) in the reactor without the need for secondary clarifier and sludge recirculation. However, there are also several reports on problems of biomass instability, long periods of granule formation (mainly when using real sewage), formation of small granules, nitrite accumulation (incomplete denitrification), and other issues. This review explores the mechanisms required for granulation in full-scale WWTP treating sanitary wastewater, including the main microbial groups present in the AGS, key granule formation parameters, reactor configurations, etc. In addition, some issues on the operation and maintenance of these full-scale systems are discussed.

Fungi as a purifying species in an Integrated Fixed Film Activated Sludge (IFAS) Bioreactor as a Biological Nitrogen Reduction System

Background: Fungi are free-living heterotrophic microorganisms, which absorb nutrients for growth andreproduction. The integrated fixed film activated sludge (IFAS) system is a beneficial technology for developingconventional activated sludge plants, which consisted of a wide range of microorganisms. Methods: Twelvewastewater samples were collected from four IFAS sites during 3 days. The samples were prepared for count andidentification. The genera of fungi were identified by macroscopic and microscopic features. The physicalchemical analyses were done according to the standard method protocols. To prevent and reduce the growth ofbacteria, 0.05 g/l of chloramphenicol was added to the synthetic wastewater. Results: The highest count of fungiwith a mean concentration was found in the Aeration tank (149 CFU/ml), whereas the lowest count of fungi wasfound in the Effluent tank (3.3 CFU/ml). The highest diversity of genera (17) was isolated in the Aeration tank,while the lowest diversity of genera (3) was isolated from the Effluent tank. The results of the physical-chemicaltests showed that the average removals of COD, TN, and TP in the IFAS fungal system were 91.76%, 91.43%,and 80.23%, respectively. Conclusions: This study on fungi and their ability in reducing nutrients called attentionto the role of the IFAS system and its potential for developing a new biological nitrogen removal technology basedon fungal treatment.

Influence of Solar Energy on the Physicochemical Parameters of Effluent Sludge and the Receiving Stream of an Oxidation Pond

Aim: This study was aimed at determining the physicochemical characteristics (such as pH, dissolved oxygen, biological oxygen demand, nitrogen, phosphorus, chloride, iron, lead, magnesium etc.) of the effluent sludge from a sewage oxidation pond and the receiving stream before and after exposure to solar energy. This is to gain a better understanding on how ultraviolet radiations from sunlight alters the physicochemical parameters inherent in the sludge and the stream. Methods and Results: Effluent sludge samples and water samples from the receiving stream were collected and exposed to solar energy over a twenty-day period. Physicochemical parameters were measured using standard methods. Results revealed that mean values of dissolved oxygen and pH increased whereas those of biological oxygen demand, ammonia nitrogen, chloride, phosphorus, iron, lead zinc and magnesium reduced over the period study. Conclusion: The findings from this study suggest that the addition of solar energy to the chains of processes in sewage treatment will produce effluents with minimal content of nutrients from organic matter and heavy metals and these will ultimately protect the receiving stream from contamination, thus contributing to human health protection.

Avaliação de estação de tratamento de esgoto com reator anaeróbio recebendo lodo de estação de tratamento de água Actiflo® / Evaluation of wastewater treatment plant with anaerobic reactor receiving sludge from water treatment plant Actiflo ®

RESUMO O objetivo deste trabalho foi analisar a disposição do lodo do decantador de uma estação de tratamento de água (ETA) com sedimentação lastreada por microareia (Actiflo®) em uma estação de tratamento de esgoto (ETE) composta de upflow anaerobic sludge blanket (UASB) e lagoa de polimento, em Ponta Grossa, Paraná. A ETE Verde operou em condição estável, com uma vazão média afluente de 213,14 L.s-1. Os UASBs operaram com tempo de detenção hidráulica (TDH) de 9,9 horas, carga hidráulica volumétrica de 2,4 m3.m-3.d-1 e carga orgânica volumétrica (COV), em função da demanda química de oxigênio (DQO), variando entre 0,75 e 1,66 kgDQO.m-3.d-1. A lagoa operou com TDH de 4,5 dias, com taxa de aplicação superficial variando entre 765 e 2.872 kgDQO.ha-1.d-1 e COV variando entre 19 e 72 gDQO.m-3.d-1. A eficiência na remoção de DQO e sólidos suspensos totais (SST) foi mantida, mesmo com o lançamento do lodo da ETA. A eficiência da ETE variou entre 80 e 86% para a remoção de DQO e entre 92 e 96% para a remoção de SST. Concluiu-se que o lançamento na rede de esgotos é uma alternativa viável de disposição do lodo do decantador da ETA Actiflo®.

ABSTRACT The objective of this paper was to analyze the disposal of decanter's sludge from a WTP with microsand ballasted sedimentation (Actiflo®) in a WWTP containing UASB reactors and polishing pond, in Ponta Grossa - PR. The WWTP Verde operated in stable condition, with an average flow tributary of 213.14 L.s-1. The UASBs operated with HRT in 9.9 hours, VHL in 2.4 m3.m-3.d-1 and OLR ranging from 0.75 to 1.66 kgCOD.m-3.d-1. The polishing pond operated with HRT in 4.5 days and OLR ranging from 765 to ­2872 ­kgCOD.ha-1.d-1, which corresponds from 19 to 72 gCOD.m-3.d-1. The efficiency of COD and TSS removal was maintained even with the release of WTP sludge. WWTP's efficiency ranged between 80% and 86% for COD removal and between 92% and 96% for TSS. It was concluded that the release in the sewage collection network is a viable alternative to disposal of the decanter's sludge from WTP Actiflo®.

Biossorção de íons Cr(III) de soluções aquosas sintéticas e efluente de curtume utilizando a macrófita aquática Pistia stratiotes / Biosorption of Cr(III) ions from synthetic aqueous solutions and tannery effluent using the macrophyte Pistia stratiotes

RESUMO O cromo é um metal tóxico amplamente utilizado em processos industriais, por isso a constante preocupação com os efluentes líquidos gerados. Uma vez lançados sem o devido tratamento podem comprometer a qualidade do corpo receptor. Este trabalho teve por objetivo analisar o processo de biossorção na remoção de íons Cr(III) de soluções aquosas sintéticas e efluente de curtume utilizando como biossorvente a macrófita aquática Pistia stratiotes in natura (PN) e quimicamente modificada (PM) com hidróxido de sódio e ácido cítrico. Realizou-se o preparo, a caracterização dos biossorventes e os experimentos de biossorção. Os estudos de equilíbrio indicaram que a capacidade máxima de biossorção foi de 58,16 e 19,80 mg g-1 para PM e PN, respectivamente. Nos testes utilizando efluente bruto de curtume, a remoção de cromo foi de 28,26% para ambos os biossorventes, e no efluente da lagoa de tratamento biológico, a maior taxa de remoção do metal foi obtida pelo biossorvente PM, com 65,44%. Os resultados demonstraram que a utilização de P. stratiotes como biossorvente apresenta-se como uma alternativa eficaz e de baixo custo, porém estudos complementares são necessários a fim de avaliar sua aplicação em escala real.

ABSTRACT Chromium is a toxic metal widely used in industrial processes, so the concern with the liquid effluents generated is constant, that once released without proper treatment can compromise the quality of the receiver body. The study aimed at analyzing the process of biosorption in removing Cr(III) ions of synthetic aqueous solutions and tannery effluent using as biosorbent the Pistia stratiotes macrophyte in natura (PN) and chemically modified (PM) with sodium hydroxide and citric acid. The preparation, characterization of the biosorbents and the experiments of biosorption were performed. Equilibrium studies indicated that the maximum biosorption capacity for PM was 58.16 mg g-1 and 19.80 mg g-1 for PN. In the tests using raw effluent from tannery, chromium removal was 28.26% for both biosorbents, and in the effluent from biological treatment lagoon, the higher rate of metal removal was obtained by biosorbent PM with 65.44%. The results showed that the use of P. stratiotes as biosorbent may be an effective and low-cost alternative and that additional studies are needed to assess its full-scale application.

Utilização do fruto seco descascado da Luffa cyllindrica como meio suporte em filtros biológicos percoladores: análise do desempenho quanto à redução da carga orgânica e considerações microbiológicas / Use of dehydrated peeled fruit of Luffa cyllindrica as support medium in biological trickling filters: analysis of performance regarding the reduction of the organic content and microbiologic considerations

RESUMO Experiências sobre o tratamento de esgoto doméstico foram realizadas em instalação piloto de filtros biológicos percoladores, em laboratório, nos quais frutos secos descascados de Luffa cyllindrica constituíram o meio suporte para o crescimento microbiológico, com o objetivo de verificar sua capacidade de remoção da matéria orgânica, medida em termos da demanda bioquímica de oxigênio e da demanda química de oxigênio. Os resultados obtidos, quando comparados com os originários de um filtro similar que utilizava pedras como meio suporte, indicaram que a Luffa cyllindrica pode substituir, em condições específicas, o meio suporte tradicional. Embora estudos microbiológicos detalhados não estivessem entre os objetivos deste estudo, observou-se também que o biofilme encontrado na Luffa cyllindrica era mais rico em espécies e apresentava estágio mais evoluído do que o biofilme encontrado nas pedras. Estudos complementares são recomendados.

ABSTRACT Domestic sewage treatment experiments were conducted in a pilot installation of biological trickling filters in laboratory, in which the peeled dehydrated fruits of Luffa cyllindrica were used as a support medium for microbiological growth, in order to verify its capacity to remove organic matter, measured in terms of biochemical oxygen demand and chemical oxygen demand. The results obtained, when compared to results from similar pilot plant using stones as supporting medium, indicated that Luffa cyllindrica can substitute, under specific conditions, the traditional support media. Although detailed microbiologic studies were not among the objectives of this study, it was also observed that the biofilm found in Luffa cyllindrica was richer in species and in a higher evolutive stage than the biofilm found in the stones. Further studies are recommended.

Nanocompósitos magnéticos para concentração/remoção de contaminantes de águas / Magnetic adsorbent nanocomposites for water treatment

Zeólitas e carvão ativado são materiais eficazes para o tratamento de efluentes devido a sua grande área superficial e possibilidades de funcionalização, que permitem o desenvolvimento de novos materiais derivados visando a processos de concentração/remoção de contaminantes, por exemplo, em águas. A preparação de nanocompósitos magnéticos e sua aplicação na remoção seletiva de poluentes em meio aquoso tornou-se viável devido as interações distintas que ocorrem entre zeólita e carvão ativado com compostos orgânicos, íons metálicos e compostos nitrogenados. Assim, novos materiais voltados para sistemas de tratamento de águas residuais e monitoramento ambiental foram desenvolvidos com base em materiais bem estabelecidos. Os nanocompósitos foram caracterizados estrutural e morfologicamente por técnicas de microscopia eletrônica de varredura, termogravimetria, espectroscopia no infravermelho, espalhamento de luz, difração de raios x, bem como suas capacidades de adsorção. Foi avaliado também a viabilidade de aplicações em métodos analíticos, como pré-concentração por extração em fase sólida magnética (M-SPE), e, para tratamento de efluentes em amostras reais. Contaminação por cromo (VI), outras espécies potencialmente tóxicas e amônio foram removidos de águas residuais, gerando produtos tratados com níveis de contaminantes suficientemente baixos para atenderem as recomendações da EPA (Environmental Protection Agency) e CONAMA (Conselho Nacional do Meio Ambiente), permitindo seu descarte na natureza. Os materiais demonstraram ser adequados para pré-concentração rápida, eficiente, economicamente competitiva e ambientalmente amigável de amostras por M-SPE para quantificação analítica de espécies orgânicas ou inorgânicas, por técnicas analíticas convencionais. Assim, foi demonstrado a possibilidade de determinação simultânea de elementos potencialmente tóxicos e de outros cátions metálicos em concentrações traço (ppb), diretamente no material compósito magnético, por espectroscopia de fluorescência de raios X de energia dispersiva (EDX), além da quantificação de traços de compostos orgânicos semi-voláteis por cromatografia emfase gasosa com detector por espectrometria de massas, aumentando a sensibilidade para além do limite nominal de detecção por essas técnicas

Zeolites and activated carbon are effective materials for the treatment of effluents due to their large surface area and functionalisation possibilities, which allow the development of new derived materials aiming at the concentration/removal of contaminants from water, for example. The preparation of magnetic nanocomposites and their application in the selective removal of pollutants in aqueous media has become feasible due to the distinct interactions that occur between zeolite and activated carbon with organic compounds, metal ions and nitrogen compounds. Thus, new materials for wastewater treatment and environmental monitoring systems were developed based on well-established materials. The nanocomposites were structural and morphologically characterized by scanning electron microscopy, thermogravimetry, infrared spectroscopy, light scattering, x-ray diffraction, as well as their adsorption capacities, viability of applications in analytical methods such as preconcentration by extraction in magnetic solid phase, M-SPE, were evaluated, and the composite materials Cmag and Zmag applied for treatment of real samples. Chromium (VI) contamination, heavy metal cations and ammonium were removed from wastewater, generating treated products with levels of contaminants low enough to meet the EPA and CONAMA recommendations, allowing their disposal in the wild. The materials have been shown to be suitable for rapid, efficient, economically competitive and environmentally friendly preconcentration of samples per M-SPE for analytical quantification of organic or inorganic species by conventional analytical techniques. Thus, it was demonstrated the possibility of simultaneous analysis of heavy metals and other metal cations in trace concentrations (ppb), directly in the magnetic composite material, by dispersive energy X-ray fluorescence spectroscopy (EDX), in addition to the quantification of traces of volatile organic compounds (VOC) by gas chromatography with mass spectrometry detector, increasing the sensitivity beyond the nominal limit of detection by these techniques

Biofloc production in activated sludge system treating shrimp farming effluent / Produção de bioflocos em sistema de lodos ativados tratando efluente de carcinicultura

ABSTRACT The release of wastewater and the shrimp feed cost are the main challenges faced by the shrimp farming industry. An alternative solution to both problems is biofloc production in a unit external to the farm, in an activated sludge system for effluent treatment. The treatment system's influent was composed of the shrimp farm wastewater supplemented with urea and sugarcane molasses. The results show that the average removal of chemical oxygen demand was 71% and the average biofloc production in the reactor was approximately 1.5g.L-1. Adding molasses to the influent contributed to the increase in the quantity and diversity of existing microorganisms that are beneficial to cultured shrimp. The mass balance of nitrogen compounds confirmed that nitrification occurred in the system. Therefore, the use of the activated sludge system is a viable and environmentally suitable alternative to produce bioflocs and shrimp farming effluent treatment.

RESUMO A geração de efluentes e o custo com a alimentação do camarão são os principais desafios enfrentados pela carcinicultura. Uma solução conjunta para ambos os problemas é a produção de bioflocos em um sistema de lodo ativado para tratamento de efluentes. Neste trabalho, o afluente ao sistema estudado era composto pelas águas residuais do cultivo de camarão suplementadas com ureia e melaço de cana-de-açúcar. Os resultados mostraram que a remoção média de demanda química de oxigênio foi de 71% e a produção média de bioflocos no reator foi de aproximadamente 1,5 g.L-1. A adição de melaço ao afluente contribuiu para o aumento da quantidade e da diversidade de microrganismos benéficos para a produção de camarão. Houve remoção de amônia e nitrificação confirmada pelo balanço de massa. Portanto, a utilização do sistema de lodos ativados é uma alternativa viável e ambientalmente adequada para produzir bioflocos e tratar efluentes de cultivo de camarão.

Adsorción del colorante azul directo 2 sobre borra de café en una columna de lecho fijo a escala de laboratorio / Adsorption of direct blue 2 dyes over a coffee grounds in a fixed-bed column at laboratory scale

RESUMEN La contaminación del agua con colorantes sintéticos, resultado de las actividades industriales, es un problema latente en la sociedad. Su presencia, aun en concentraciones muy bajas, influye drásticamente en los procesos de fotosíntesis, porque impide la penetración de la luz, afectando la vida acuática e, incluso, la salud humana. La adsorción con carbón activado es una de las técnicas más empleadas para remover el color de los efluentes, pero sus altos costos han dirigido la atención de los investigadores hacia el estudio de materiales adsorbentes provenientes, principalmente, de la agroindustria. Este artículo presenta un estudio sobre la remoción del colorante azul directo 2 en disolución acuosa sobre borra de café sin tratar y modificada a 30±1°C, en una columna empacada. Se realizó la caracterización fisicoquímica de los adsorbentes, que incluye la evaluación de las propiedades de textura, mediante isotermas de adsorción, con N2 a 77K, la identificación y cuantificación de grupos funcionales orgánicos, con FTIR y el método de Boemh. El estudio en columna evaluó el efecto de la altura del lecho del adsorbente (Z = 3 y 6cm), el flujo volumétrico (Qv= 2 y 4cm3min-1) y la concentración inicial (Co = 8 y 14mgdm-3), sobre el tiempo de ruptura y la capacidad de adsorción. Los datos experimentales de las curvas de ruptura se ajustaron al modelo BDST (Bed Depth Service Time). Los resultados muestran que el rendimiento de la columna mejora con el incremento de Z y la disminución de Qv y Co, siendo la concentración inicial, el factor con mayor significancia.

ABSTRACT Water bodies contaminated with synthetic dyes from industrial activities is a latent problem in our society. Even in low concentration it influences drastically in photosynthesis process because it blocks sun rays affecting both life in water and human health as well. Adsorption with activated carbon is one of the most used techniques to remove dyes from effluents, but high costs have lead researchers to examine adsorbents materials coming from agroindustry. This article introduces a research about direct blue 2 removal in water solution over coffee grounds untreated and modified at 30±1°C in a packed column. A physicochemical characterization was carried out in adsorbents that involves the test of texture properties using isotherms of adsorption with N2 at 77K, the identification and quantification of organic functional groups with FTIR and the Boemh method. The study in column, tested the effect of the height of the bed of the adsorbent (Z = 3 y 6cm), the volumetric flow (Qv = 2 y 4cm3min-1) and the initial concentration (Co = 8 y 14mgdm-3) at the breakthrough time and the capacity of adsorption. The experimental data of breakthrough curves were fitted to BDST (Bed Depth Service Time) models. The results show that performance in the column improves as Z increases and Qv y Co decreases, being the initial concentration the factor with main significance.

Estimaciones del consumo de drogas ilícitas derivadas del análisis de aguas residuales: Una revisión crítica / Illicit drug consumption estimations derived from wastewater analysis: A critical review

Resumen La medición cuantitativa de drogas ilícitas en aguas residuales puede proporcionar información objetiva sobre los patrones y tendencias del uso de psicotrópicos en la comunidad. Se analizó la presencia de psicoactivos en plantas de tratamiento para aguas residuales y en el medio ambiente por epidemiología de alcantarillado, mediante una revisión sistemática de 2008-2017 por medio de los descriptores controlados: "drogas ilícitas", "plantas de tratamiento de aguas residuales" y "ambiente" hecha en las bases de datos Medline vía PubMed, SciELO, BVS vía LILACS y Google Académico. La búsqueda arrojó 439 estudios y fueron seleccionados 34 estudios para análisis. Los años de publicación variaron, siendo 2016 el de mayor de publicaciones (diez), seguido de 2014 y 2012 (cinco), 2017, 2013, 2010 (tres), 2011 (dos), 2015, 2009 y 2008 (uno cada uno). Los resultados mostraron la presencia de indicadores químicos de las drogas clásicas cocaína y cannabis. La investigación sobre la presencia de drogas ilícitas, particularmente como compuestos activos en el medio ambiente, es vital para mejorar el conocimiento de los tipos consumidos, su prevalencia; siendo capaz desplegar para analizar la exposición y el impacto de estos compuestos en el medio ambiente y la salud pública. Los resultados de esta revisión han resaltado que la epidemiología basada en aguas residuales es un enfoque útil y poderoso.

Abstract Quantitative measurement of illicit drugs in wastewater can provide objective information on community drug use patterns and trends. The presence of illicit drugs in treatment plants for wastewater and in the environment was analyzed by sewege epidemiology. It is a systematic review from 2008-2017 by means of the controlled descriptors: "illicit drugs", "wastewater treatment plants" and "environment" performed on Medline databases via PubMed, SciELO, BVS via LILACS and Google Scholar. The search yielded 439 studies. 34 studies were selected for analysis. The years of publication varied, with 2016 being the highest of publications (ten), followed by 2014 and 2012 (five), 2017, 2013, 2010 (three), 2011 (two), 2015, 2009 and 2008 (one each). The results showed the presence of chemical indicators of the classic drugs cocaine and cannabis. Research on the presence of illicit drugs, particularly as active compounds in the environment, are vital to improve knowledge of the types consumed, its occurrence; being able to unfold to analyze the exposure and the impact of these compounds in the environment and public health. The results of this revision have highlighted that wastewater-based epidemiology is a useful and powerful approach.

Desenvolvimento de um biorreator de grânulos aeróbios para tratamento de água residuária sintética e reativação do sistema após parada prolongada / Development of an aerobic granular sludge bioreactor for simulated wastewater treatment and system reactivation after prolonged shutdown

RESUMO Este trabalho teve por objetivo produzir lodo granular aeróbio num reator em batelada sequencial não tubular, uma geometria diferente da usualmente utilizada nesses sistemas. Este reator foi inoculado com lodo ativado proveniente de uma estação de tratamento de esgoto municipal. O reator foi operado com ciclos de seis horas, com cinco horas de reação totalmente aeróbia. O efluente simulado continha um derivado de amido usado na indústria têxtil. A indução da granulação foi conseguida por meio da redução gradual do tempo de sedimentação, verificando-se que este é um parâmetro crítico do sistema. Após estabilização, com um tempo de sedimentação de 3 minutos, obteve-se um índice volumétrico de lodo de 25 mL.gSST-1, uma concentração de biomassa de 7 gSST.L-1 e uma eficiência de remoção da demanda química de oxigênio de 88%. Os grânulos obtidos foram armazenados úmidos durante 7 meses, a 4 e 25ºC, obtendo-se resultados excecionais na repartida dos reatores, com rápida recuperação das suas características de sedimentação, taxa de crescimento, estrutura e integridade granulares.

ABSTRACT This study aimed to produce aerobic granular sludge in a non-tubular sequencing batch reactor, which is an unusual geometry in these systems. This reactor was inoculated with activated sludge from a municipal wastewater treatment plant. The reactor was operated in cycles of six hours, with five hours of fully aerobic reaction. The simulated wastewater contained a starch derivative used in the textile industry. Granulation was induced by gradually reducing the settling time; therefore, this is a critical parameter of the system. After stabilization, with a sedimentation time of 3 minutes, a Sludge Volume Index after 30 minutes of settling of 25 mL.gSST-1, a biomass concentration of 7 gTSS.L-1 and a Chemical Oxygen Demand removal of 88% were obtained. The granules were stored wet for 7 months at 4 and 25ºC, yielding exceptional results in the re-start of the reactor, with rapid recovery of their sedimentation characteristics, growth rate, and granular structure and integrity.