Remoção biológica de nitrato em ��gua de abastecimento humano utilizando o endocarpo de coco como fonte de carbono

The groundwater quality has been compromised as a result of the intensification of human activities over the years. Groundwater contamination by nitrate is one of the effects of this degradation, a socio-environmental problem that affects many regions of the world and particular the city of Natal (RN). Developing techniques for nitrate removal in water is intended to eliminate or reduce the concentration of this compound, and those that involve biological processes have produced economic and environmental advantages. This study proposes a technology for biological removal of nitrate in water supply for humans, using the endocarp s coconut as a carbon source and bacteria support. The experiments were performed in pilot scale anoxic, testing different areas of the substrate surface. Results showed high rates nitrate removal during the monitoring period, noting the occurrence of denitrification after the beginning of system operation. The best performance was achieved in the treatment system containing substrate surface area increased, indicating that the decrease in the endocarp size contributed to increased bacterial activity, improving the ability to remove nitrate. About the quality analyzed aspects of water, it was found that the proposed technology has the potential water use for human consumption

Remoção de nitrogênio em biofiltros aerado e an��xico, com alto ��ndice de vazios e sem remoção de lodo

The improper disposal of nitrogen in receiving water courses causes problems such as toxicity to living beings through the consumption of oxygen to meet the nitrogen demand, eutrophication and nitrate contamination of aquifers. For this reason it is often necessary to be carried out complementary treatment of wastewater to eliminate or reduce the concentration of this compound in the wastewater. The objective of this study is to evaluate the biological removal of nitrogen compounds using submerged aerated and anoxic filters as post-treatment of an anaerobic system, with low cost and innovative technology, which in previous studies has shown high removal efficiency of organic matter and great potential biological nitrogen compounds removal. The simple design with perforated hoses for air distribution and filling with plastic parts proved to be very efficient in relation to organic matter removal and nitrification. The system presented, in the best stage, efficiency in converting ammonia to nitrate by 71%, and produced a final effluent concentration below 10 mg / L of NH3-N. In addition, carbon concentration was removed by 77%, producing final effluent with 24 mg/L COD. However, denitrification in anoxic filter was not effective even with the addition of an external carbon source. There was a reduction of up to 56% of nitrogen caused by the process of simultaneous nitrification and denitrification (SND). The high voids space presented by this type of support material coupled with direct aeration of the sludge, allows the respiration of biomass retained between the endogenous phase, increased cell retention time and sludge retention capacity, producing a final effluent with turbidity less than 5 UT and total suspended solids around 5.0 mg/L

Caracteriza����o espacial de reservat��rios do semi��rido em fun����o da qualidade da ��gua atrav��s do uso de componentes principais

A regi��o semi��rida sofre escassez h��drica. A fim de regularizar a disponibilidade h��drica nos per��odos de estiagem, s��o constru��das barragens. No entanto, a qualidade da ��gua armazenada tem sofrido os efeitos do descarte irregular de res��duos no meio ambiente e das atividades antr��picas exercidas nas bacias hidrogr��ficas. A degrada����o h��drica pode ser constatada a partir do monitoramento dos par��metros de qualidade da ��gua. Estes dados podem ser analisados atrav��s de m��todos estat��sticos tais como a An��lise de Componentes Principais e a an��lise de agrupamento, que seleciona indiv��duos com caracter��sticas semelhantes. O objetivo deste trabalho �� realizar oagrupamento dos reservat��rios do Rio Grande do Norte, com base nos par��metros de qualidade da ��gua, para a identifica����o de grupos homog��neos de reservat��rios em termos de fontes de polui����o. Ser��o objeto desse estudo as bacias Piranhas-A��u, Apodi-Mossor��, Trair��, Potengi e Cear��-Mirim. Os par��metros merc��rio, chumbo, cromo, f��sforo total, nitrogênio total e zinco contribu��ram para a forma����o da primeira componente principal, que pode indicar polui����o por metais pesados; s��lidos totais, DBO, OD e cobre, para a segunda componente, que pode ser indicativo de polui����o por matéria orgânica e atividades antr��picas; e clorofila a , c��dmio e n��quel, para a terceira componente, que pode indicar eutrofiza����o e polui����o por metais pesados. De posse das componentes principais se procedeu o agrupamento dos reservat��rios, formando-se quatro grupos distintos. Os grupos 1 e 2 s��o constitu��dos por reservat��rios da Bacia Piranhas-A��u, que apresentou maiores valores de metais pesados. O grupo 3, constitu��do por reservat��rios das bacias Cear��-Mirim, Potengi e Trair��, apresentou maiores valores de DBO e s��lidostotais e o grupo 4 �� formado por reservat��rios da Bacia Apodi-Mossor��. Nas Bacias do Trar�� e Piranhas-A��u deve ser coibido o lan��amento desordenado de efluentes e fontes de polui����o difusas, e implantado um sistema de coleta de esgoto para minimizar a polui����o por matéria org��nica

Remoção de Microalgas de efluentes de lagoas de estabiliza����o utilizando biofiltro

This research evaluated the microalgae removal produced in a stabilization pond system using biofilters as post-treatment, besides characterizing the effluents of stabilization ponds and filters in relation to concentrations of algal biomass (chlorophyll a and suspended solids), organic matter (BOD and COD), total phosphorus, orthophosphate, pH and dissolved oxygen, and tried to correlate physicochemical parameters with chlorophyll "a". It was held at the Ponta Negra ETE which is constituted by three stabilization ponds, with a primary facultative pond and two of maturation. For the algae removal were used two submerged bio-filters: the filter FPF (Facultative Pond Filter), fed with facultative pond effluent; and the filter MPF (Maturation Pond Filter), fed with second maturation pond effluent. The filling material of both filters was predominantly gravel no. 2, although it contains portions of gravel no. 1 and no. 3. The filters operating conditions were bad, they were nearly 10 years without maintenance, without cleaning or removal of sludge since the time of its construction, and part of the filling material may be obstruct. Despite poor operating conditions were obtained satisfactory results, in level of posttreatment. Removal efficiencies in relation to BOD and COD were 7 and 25% in FPF and 9 and 19% and in MPF, respectively. In relation to TSS efficiencies in MPF and FPF were 37 and 20%, respectively. As for the chlorophyll "a" removal, the FPF efficiency was 44% and the MPF was 40%. There was 50% of consumption of dissolved oxygen, on average, within the filters. Two profiles were performed in the filters, and it was possible to conclude that variations throughout the day were not statistically significant, and that, regardless of the time of collection, they would have the same representation comparing to the time of data collection (7 am) and the daily average, although individual variations throughout the day have been shown to be significant. Another important observation is that the correlations between Chlorophyll a and TSS were bigger and more significant in the effluent of the filters than in the effluent of the ponds

Diagn��stico ambiental das ��guas do estu��rio Jundia��-Potengi pela determina����o dos ��ndices de qualidade da ��gua e toxidez

This study is an environmental diagnosis of the Jundia��-Potengi/RN estuarine system waters, using calculations of pollution indicator indices such as the Water Quality Index (WQI) and the Toxicity Index (TI). The samples were collected at twelve points on the estuary, at high and low tide, between August and November 2007, over four campaigns. The study area, located in a high impact region, has various activities on its banks such as: discharge of untreated or undertreated domestic and industrial sewage, shrimp farming, immunizer stabilization lakes, riverside communities, etc. All the parameters analyzed were compared to the limits of CONAMA Resolution No. 357 of 2005 for healthy and saline Class 1 waters. The results found prove the impact caused by various activities, mainly the parameters related to the presence of organic material, such as DQO, DBO, COT and thermotolerant colliforms. The IQA for most of the collection points was of medium quality. For the metals, although values above the Resolution limits were found, most of them were lower than the detection limits of ICP-OES used, indicating that they tend to be transported by the dynamic of the tides or rainfall and are deposited in bottom sediments, resulting in a TI of 1.0 in this water, when they are absent, which occurs in most cases, or 0.0, when heavy metals are found in these waters

Avalia����o das condi����es qu��mica e f��sica dos sedimentos do estu��rio Jundia��-Potengi

The aim of this study was to quantify the presence of major and minor elements in the sediments of the Jundia��-Potengi estuary, bordering the municipalities of Maca��ba, Natal and S��o Gon��alo do Amarante in the state of Rio Grande do Norte, Brazil, considering the evidence of anthropic activity along this estuary, resulting in pollution by treated and untreated wastewaters as well as those produced by industry and shrimp farming. The assessment of the environmental status of this estuary was based on physical-chemical parameters, such as granulometry, organic matter and the major (Al, Fe, Mn and P) and minor (Cd, Cr, Cu, Ni, Pb and Zn) elements found in sediment samples. Two collections were made at 12 georeferenced points along the channel of the estuary at different times. Granulometric analysis was carried out and the percentage of organic matter was determined. The sediments were microwave digested using acid digestion and quantitative analyses of the elements Al, Fe, Cd, Cr, Cu, Mn, Ni, P, Pb and Zn were performed by inductively coupled plasma optical emission spectrometry. Sediment analysis followed the methodology proposed by US EPA 3051A for total elements analysis. The small correlation between the organic matter and the elements studied here suggests that they are of geochemical rather than anthropic origin. The analytical results obtained from the bottom sediment samples in the study area show that the concentration of elements was below the reference values for standard shales (Turekian & Wedepohl, 1961) at the vast majority of points analyzed, ruling out a possible contamination by metals

Caracteriza����o e aplica����o de vermicultura natural e quimicamente modificada na adsor����o de azul de metileno

Chemical modification of clays has been extremely studied in the search for improvements of their properties for use in various areas, such as in combating pollution by industrial effluents and dyes. In this work, the vermiculite was chemically modified in two ways, characterized and evaluated the adsorption of methylene blue dye. First was changed with the addition of a surfactant (hexadecyltrimethylammonium bromide, BHTA) making it an organophilic clay and then by adding an acid (HCl) by acid activation. Some analyzes were performed as X-ray fluorescence (FRX), X-ray diffraction (DRX), adsorption isotherms of methylene blue dye, infrared (FTIR) , scanning electron microscopy (SEM), thermal gravimetric analysis and spectroscopy energy dispersive (EDS). Analysis by FRX of natural vermiculite indicates that addition of silicon and aluminum, clay presents in its structure the magnesium, calcium and potassium with 16 % organic matter cations. The DRX analyzes indicated that the organic vermiculite was an insertion of the surfactant in the space between the lamellae, vermiculite and acid partial destruction of the structure with loss of crystallinity. The adsorption isotherms of methylene blue showed that there was a significant improvement in the removal of dye to the vermiculite with the addition of cationic surfactant hexadecyltrimethylammonium bromide and treatment with acid using HCl 2 mol/L. In acid vermiculites subsequently treated with surfactant, the adsorption capacity increased with respect to natural vermiculite, however was much lower compared vermiculite modified with acid and surfactant separately. Only the acidic vermiculite treated with surfactant adjusted to the Langmuir model. As in the infrared spectrometry proved the characteristics of natural vermiculite. In the organic vermiculite was observed the appearance of characteristic bands of CH3, CH2, and (CH3)4N. Already on acid vermiculite, it was realized a partial destruction with decreasing intensity of the characteristic band of vermiculite that is between 1074 and 952 cm-1. In the SEM analysis, it was observed that there was partial destruction to the acid treatment and a cluster is noted between the blades caused by the presence of the surfactant. The TG shows that the higher mass loss occurs at the beginning of the heating caused by the elimination of water absorbed on the surface between layers. In the organic vermiculite also observed a loss of mass between 150 and 300 ��C caused decomposition of the alkylammonium molecules (surfactants)

Rota����o de culturas e propriedades f��sicas e qu��micas em Latossolo Vermelho de Cerrado sob preparo convencional e semeadura direta em ado����o

O manejo inadequado do solo tem promovido a degrada����o de suas propriedades f��sicas, qu��micas e biológicas. O objetivo deste trabalho foi avaliar, ap��s tr��s anos da instala����o de sistemas de manejo do solo, os efeitos da rota����o com adubo verde, soja ou milho (ver��o) e feij��o de inverno, sendo utilizadas as seguintes esp��cies na aduba����o verde: mucuna-preta, milheto, crotal��ria e guandu, nas propriedades f��sicas e qu��micas de um Latossolo Vermelho distrof��rrico e na produtividade das culturas. Outro tratamento foi adicionado como alternativa �� aduba����o verde, o pousio. Os sistemas de manejo do solo foram: semeadura direta n��o consolidada e preparo convencional. O estudo foi realizado em Selv��ria-MS, no ano agr��cola de 1999/2000. O delineamento experimental foi em blocos casualizados com parcelas subdivididas e quatro repeti����es. O sistema de semeadura direta, ap��s tr��s anos de instalada a rota����o, degradou mais as propriedades f��sicas do solo na camada superficial. Por outro lado, neste sistema e camada de solo, houve acr��scimo no teor de matéria orgânica e no pH, bem como na produtividade do milho, superior �� do sistema de preparo convencional. O feij��o em rota����o �� cultura do milho, na semeadura convencional, e em rota����o �� soja, na semeadura direta, foi a melhor op����o quanto �� produtividade.

Recupera����o do subsolo em ��rea de empr��stimo usada para constru����o de hidrel��trica

��reas degradadas referem-se a ecossistemas alterados, onde perdas ou adi����es s��o as formas mais comuns de perturba����es e degrada����es ambientais. As ��reas de empr��stimo em hidrel��tricas podem ser consideradas ��reas degradadas, pois delas foram retirados os horizontes superficiais do solo. Portanto, este trabalho teve como objetivo estudar a recupera����o de atributos f��sicos e da matéria orgânica do subsolo de um Latossolo Vermelho distr��fico, degradado pela retirada de solo para constru����o de usina hidrel��trica, por meio de aduba����o verde e aplica����o de calc��rio e gesso. A pesquisa foi implantada em 1992 e os tratamentos constitu��ram-se de: testemunha (solo mobilizado e vegeta����o espont��nea); mucuna-preta; guandu at�� 1994, seguido por feij��o-de-porco; calc��rio + mucuna-preta; calc��rio + guandu at�� 1994, seguido por feij��o-de-porco; calc��rio + gesso + mucuna-preta e calc��rio + gesso + guandu at�� 1994, seguido por feij��o-de-porco. Os tratamentos foram implantados seguindo o esquema em blocos casualizados com quatro repeti����es. Ap��s sete anos, em 1999, foram avaliadas a porosidade do solo, a macroporosidade, a microporosidade, a densidade do solo, matéria orgânica e a produ����o de massa seca da braqui��ria. Os tratamentos adotados est��o contribuindo para a recupera����o dos atributos f��sicos do subsolo exposto, e o tratamento com mucuna-preta, sem a corre����o do solo, tem se mostrado mais promissor. Os efeitos da recupera����o do solo est��o atingindo a profundidade de 0,00-0,10 m.

Col��mbolos (arthropoda: hexapoda: collembola) numa ��rea de caatinga do nordeste brasileiro

Edaphic ecosystems are the basis for the production of terrestrial biological resources and their dynamics affect not only the natural environment but also society and their economic activities. In Caatinga biome, the semi-arid climate associated with an inadequate soil management has increased the degradation and loss of productive potential of the soil. In this context, the study of soil fauna, including springtails, becomes an important indicator of soil quality. This study aimed to evaluate the fauna of Collembola in an area of Caatinga of Rio Grande do Norte State and the influence of biotic and abiotic factors, such as soil, vegetation and climate characteristics, on the structure of the taxocenosis. The environmental variables which were used were the following ones: granulometry (represented by the proportion of sand), quantity of organic matter and soil pH, richness, density and aerial biomass of the vegetal structure, and necromass. We used pitfall traps intending to collect specimens of the epiedaphic fauna of Collembola in 30 points located on Caua��u Farm, Jo��o C��mara, RN, in July (rainy season) and November (dry season) 2011. We collected 5513 individuals of 15 species distributed in 13 genera and 9 families of Collembola. Five of the recorded species are new to science, confirming the expected high degree of endemism for Caatinga biome, and the highest abundance was recorded in the rainy season, which suggests Collembola sensitivity to low humidity. Four species were more abundant in the dry season, all of them belonged to the Order Entomobryomorpha. Results of statistical analyzes suggest that plant species richness, aerial biomass of vegetal structure, proportion of sand in the soil, pH and humidity are the main influences to the abundance of Collembola in the region studied

Studies on the electrochemical disinfection of water containing Escherichia coli using a Dimensionally Stable Anode

Funda����o de Amparo �� Pesquisa do Estado de S��o Paulo (FAPESP)

Electrolytic treatment applied to the industrial effluent containing persistent wastes monitored by Bartha respirometric assays

Conselho Nacional de Desenvolvimento Cient��fico e Tecnol��gico (CNPq)

Performance of the constructed wetland system for the treatment of water from the corumbata�� river

Funda����o de Amparo �� Pesquisa do Estado de S��o Paulo (FAPESP)

Efficiency of bioaugmentation in the removal of organic matter in aquaculture systems

Funda����o de Amparo �� Pesquisa do Estado de S��o Paulo (FAPESP)

Phosphorus, nitrogen, and carbon contents of macrophytes in lakes lateral to a tropical river (Paranapanema River, S��o Paulo, Brazil)

Funda����o de Amparo �� Pesquisa do Estado de S��o Paulo (FAPESP)