Incorporação de resíduo de perfuração em matriz cerâmica: estabilização por solidificação

One of the waste generated during the drilling of oil wells are gravel which are impregnated of drilling fluid. This residue consists of highly toxic chemicals, including toxic metals. This study suggests an alternative process to the treatment of this waste, by incorporating it the form of raw material in the ceramic matrix , and by solidification and stabilize the metals present, Aluminum (Al), Iron (Fe), Manganese (Mn) and Zinc (Zn). The raw materials were characterized by the techniques of X ray fluorescence (FRX), X ray diffraction (DRX), laser granulometry (GL), thermogravimetry (TG) and differential thermal analysis (ADT). To evaluate the percentage of gravel effect the environmental and technological properties were obtained from formulations containing 0, 10 and 20 % by weight of gravel in the ceramic matrix. After sintering at temperatures 1080, 1120 and 1160 °C, the samples were tested for water absorption, the linear shrinkage firing, voltage of rupture and solubility. The results obtained showed that the stabilization by solidification, is a viable alternative to safe disposal of waste drilling. Ceramics products can be used in the manufacture of solid bricks

Remoção de carbonatos para otimizar a biolixiviação de rejeito calcopirítico empregando consórcio de microrganismos

The bioleaching of chalcopyrite has not been applied on a commercial scale due to the low process efficiency, so this process has been extensively studied in recent years. The bioleaching of chalcopyrite tailings becomes even more difficult by the presence of higher amounts of impurities, among them are the carbonates. The presence of carbonates in the ore promotes the increase in pH of the solution and may inhibit the development of bioleaching. Therefore, this research aims to apply the acid treatment for optimization of bioleaching process, in order to recover the lost copper throughout the process besides reducing the content of this toxic metal in the tailings pond. The removal and recovery of toxic metals is very important in protecting the environment and human health. The bioleaching experiments were performed in two stages, the first made up using the pre-treated tailing with sulfuric acid in bioleaching, and the second was made using the tailing without treatment with sulfuric acid addition at the beginning of bioleaching. The acid treatment was carried out in bioreactors with three different volumes of H2SO4 96% and a control experiment. All bioleaching experiments were performed in triplicate over a control, without addition of inoculum. The results showed that acid treatment was effective in removal of carbonates and managed to promote a good performance in the bioleaching of chalcopyrite in both steps studied, it is demonstrated that circa 47% copper recovery can be achieved.

Remoção de carbonatos para otimizar a biolixiviação de rejeito calcopirítico empregando consórcio de microrganismos

The bioleaching of chalcopyrite has not been applied on a commercial scale due to the low process efficiency, so this process has been extensively studied in recent years. The bioleaching of chalcopyrite tailings becomes even more difficult by the presence of higher amounts of impurities, among them are the carbonates. The presence of carbonates in the ore promotes the increase in pH of the solution and may inhibit the development of bioleaching. Therefore, this research aims to apply the acid treatment for optimization of bioleaching process, in order to recover the lost copper throughout the process besides reducing the content of this toxic metal in the tailings pond. The removal and recovery of toxic metals is very important in protecting the environment and human health. The bioleaching experiments were performed in two stages, the first made up using the pre-treated tailing with sulfuric acid in bioleaching, and the second was made using the tailing without treatment with sulfuric acid addition at the beginning of bioleaching. The acid treatment was carried out in bioreactors with three different volumes of H2SO4 96% and a control experiment. All bioleaching experiments were performed in triplicate over a control, without addition of inoculum. The results showed that acid treatment was effective in removal of carbonates and managed to promote a good performance in the bioleaching of chalcopyrite in both steps studied, it is demonstrated that circa 47% copper recovery can be achieved.

Diagnóstico ecotoxicológico dos efluentes lançados no complexo estuarino do Jundiaí/Potengi, Natal/RN

Untreated effluents that reach surface water affect the aquatic life and humans. This study aimed to evaluate the wastewater s toxicity (municipal, industrial and shrimp pond effluents) released in the Estuarine Complex of Jundiaí- Potengi, Natal/RN, through chronic quantitative e qualitative toxicity tests using the test organism Mysidopsis Juniae, CRUSTACEA, MYSIDACEA (Silva, 1979). For this, a new methodology for viewing chronic effects on organisms of M. juniae was used (only renewal), based on another existing methodology to another testorganism very similar to M. Juniae, the M. Bahia (daily renewal).Toxicity tests 7 days duration were used for detecting effects on the survival and fecundity in M. juniae. Lethal Concentration 50% (LC50%) was determined by the Trimmed Spearman-Karber; Inhibition Concentration 50% (IC50%) in fecundity was determined by Linear Interpolation. ANOVA (One Way) tests (p = 0.05) were used to determinate the No Observed Effect Concentration (NOEC) and Low Observed Effect Concentration (LOEC). Effluents flows were measured and the toxic load of the effluents was estimated. Multivariate analysis - Principal Component Analysis (PCA) and Correspondence Analysis (CA) - identified the physic-chemical parameters better explain the patterns of toxicity found in survival and fecundity of M. juniae. We verified the feasibility of applying the only renewal system in chronic tests with M. Juniae. Most efluentes proved toxic on the survival and fecundity of M. Juniae, except for some shrimp pond effluents. The most toxic effluent was ETE Lagoa Aerada (LC50, 6.24%; IC50, 4.82%), ETE Quintas (LC50, 5.85%), Giselda Trigueiro Hospital (LC50, 2.05%), CLAN (LC50, 2.14%) and COTEMINAS (LC50, IC50 and 38.51%, 6.94%). The greatest toxic load was originated from ETE inefficient high flow effluents, textile effluents and CLAN. The organic load was related to the toxic effects of wastewater and hospital effluents in survival of M. Juniae, as well as heavy metals, total residual chlorine and phenols. In industrial effluents was found relationship between toxicity and organic load, phenols, oils and greases and benzene. The effects on fertility were related, in turn, with chlorine and heavy metals. Toxicity tests using other organisms of different trophic levels, as well as analysis of sediment toxicity are recommended to confirm the patterns found with M. Juniae. However, the results indicate the necessity for implementation and improvement of sewage treatment systems affluent to the Potengi s estuary

Desenvolvimento de membranas porosas de alumina para fins de tratamento de efluente industrial têxtil

Textile production has been considered as an activity of high environmental impact due to the generation of large volumes of waste water with high load of organic compounds and strongly colored effluents, toxic and difficult biodegradability. This thesis deals with obtaining porous alumina ceramic membranes for filtration of textile effluent in the removal of contaminants, mainly color and turbidity. Two types of alumina with different particle sizes as a basis for the preparation of formulation for mass production of ceramic samples and membranes. The technological properties of the samples were evaluated after using sintering conditions: 1,350ºC-2H, 1,450ºC-30M, 1,450ºC-2H, 1,475ºC-30M and 1,475ºC-2H. The sintered samples were characterized by XRD, XRF, AG, TG, DSC, DL, AA, MEA, RL, MRF-3P, SEM and Intrusion Porosimetry by Mercury. After the characterization, a standard membrane was selected with their respective sintering condition for the filterability tests. The effluent was provided by a local Textile Industry and characterized at the entry and exit of the treatment plant. A statistical analysis was used to study the effluent using the following parameters: pH, temperature, EC, SS, SD, oil and grease, turbidity, COD, DO, total phosphorus, chlorides, phenols, metals and fecal coliform. The filtered effluent was evaluated by using the same parameters. These results demonstrate that the feasibility of the use of porous alumina ceramic membranes for removing contaminants from textile effluent with improved average pore size of 0.4 micrometre (distribution range varying from 0,025 to 2.0 micrometre), with total porosity of 29.66%, and average percentages of color removal efficiency of 89.02%, 92.49% of SS, turbidity of 94.55%, metals 2.70% (manganese) to 71.52% (iron) according to each metal and COD removal of 72.80%

Avaliação da correlação entre os parâmetros, carbono orgânico total e elementos tóxicos, em solo de um posto de serviço e revenda de combustíveis

Today a major responsibility for the contamination of soil and groundwater and surface water are establishments known as gas stations of fuel which has attracted increasing attention from both the general population as the state agencies of environmental control due to leaks in storage tanks and mainly to disruption of pipe corrosion of tanks and pumping. Other services, like oil changes and car wash are also causes for concern in this type of establishment. These leaks can cause or waste produced, and the contamination of aquifers, serious health problems and public safety, since most of these stations located in urban areas. Based on this, the work was to evaluate soil contamination of a particular service station and fuel sales in the city of Natal, through the quantification of heavy metals like Cd, Cu, Cr, Ni, Pb, Zn of total organic carbon (TOC) and organic matter using different techniques such as optical emission spectrometry with inductively coupled plasma source (ICP OES), Total Organic Carbon analyzer and gravimetric analysis respectively. And also to characterize the soil through particle size analysis. Samples were taken in 21 georeferenced points and collected in the same period. The soils sampled in sampling stations P3, P5, P6, P10, P11, P12, P13, P14, P15, P17, P18 and P20 showed the smallest size fractions ranging from fine sand to medium sand. The other study sites ranged from fine sand to medium sand, except the point P8 showed that only the type size medium sand and P19, indicating a particle size of the coarse type. The small correlation of organic matter with the elements studied in this work suggests that these are not of anthropogenic origin but geochemical support

Estudo da remoção de Ba2+, Ni2+, Cd2+, Cu3+, Cr3+, Sr2+, Zn2+ por eletrocoagulação em água associada à produção de petróleo

Among the waste generated in the petrochemical industry water associated with oil production is the most important. It is considered one of the great challenges due to the presence of considered toxic chemicals present in this composition. The presence of these substances difficult to reuse the water associated with the enhanced recovery processes, so that prior to their reuse or disposal, treatment is necessary. This paper aimed to study the removal efficiency of chemical species: Ba2+, Ni2+, Cd2+, Cu2+, Cr3+, Sr2+ and Zn2+, present in the composition of the water associated with oil production by electrocoagulation. The evaluation of removal of these chemical species was performed by laboratory tests using electrochemical batch reactors and continuous flow. Initial tests were performed with electrocoagulation of synthetic wastewater in batch reactor using iron electrode. Results of removal of Zn2+ and Ni2+ were 78 % and 59 % respectively. While the percentage of removed Ba2+ was 19 % by 30 minutes of treatment and by applying current of 1.10 A. The tests were performed on effluent batch reactor applying the electrochemical technique with stainless steel electrodes 304, the objective was to remove part of the dispersed oil and also of organic compounds in the effluent. Under the experimental conditions used, the maximum result was obtained TOG was 60 % and TOC was approximately 50 % compared to the initial concentration. In the experiments carried out in continuous reactor, with effluent semisynthetic, have been used electrodes of iron and aluminum and the results were 100 % removal of Cd2+, Cu2+, Cr3+ and Zn2+ and 77 % of Sr2+. These percentages were only attainable through the use of the iron electrode. However, when the electrode was replaced by aluminum, there was a reduction in the percentage of removal to 65 %, using the same flow rate and current. Therefore according to the results obtained using the iron electrode was more effective in removing these metals and the conditions of lower current and lower flow rate was satisfactory, as observed in the experimental design adopted

Uso e ocupação do solo e a concentração de metais pesados no sedimento e na água: bacia do rio Pitimbu

The accelerated growth of urban regions have produced relevant effects on water resources. Urban regions need an adequate institutional structure that can be able to face environmental demands and the adverse effects of land use on water resources. This study aims at analysing land use effects on heavy metals concentration in sediments and water, as well as making a comparative analysis involving water physical-chemical parameters. Applied methodology included both in loco water parameters measurement and water and bed sediment sampling at 8 sections along the fluvial system. Sample analysis was performed in laboratory in order to measure heavy metal concentrations. It was measured metal concentrations of Al, Cu, Pb, Cd, Fe, Ni and Zn. Once the samples were subjected to acid digestion (method 3050B), concentration values were measured by using atomic absorption spectrometry by flame (ICP-FLAA). The analysis results were compared with normative reference, these standards is intended to assess the risks of toxic substances in sediment and water management programs. The normative reference used in this work were: a) Ontario Ministry of the Environment and Energy (OMEE, 1993) b) Normative Netherlands (VROM, 2000); c) Normative Canadian (CCME, 1999); d) United States Environmental Protection Agency (USEPA, 1977), e) CONAMA Resolution No. 344/2004; f) CONAMA Resolution No. 357/2005. The high concentrations of iron (38,750 mg.g-1), Lead (1100 mg.g-1), Nickel (100 μg.g-1) and zinc (180 μg.g-1) detected sediments confirm the state of degradation of the aquatic system. Iron concentrations (1.08 mg.L-1), Aluminum (0.6 mg.L-1) and phosphorus (0.05 mg.L-1) present in the water are outside the established standards for human consumption

Avaliação da genotoxicidade das águas do lençol freático sob a Universidade Federal do Rio Grande do Norte

The groundwater represents the most important freshwater supply of planet. Dailly, in all world a great amount of toxic and genotoxic material reaches the aquatic systems, mainly the aquifers. The Barreiras aquifer through of five water wells is responsible for the supplying of Universidade Federal do Rio Grande do Norte (UFRN). All water wells are polluted with nitrate and some heavy metals, two of them were disabled. The genotoxicity of groundwater samples from Barreiras Aquifer in UFRN was assessed using the Allium cepa test, the Ames test and the Salmonella typhymurium microsuspension test (Kado test). For the Allium cepa test the influence of the groundwater samples collected on macroscopic (root length, colour and form) and microscopic (root tip mitotic index, chromosome aberrations and micronucleus) parameters was examined. All water samples caused a significant increase of the chromosome and mitotic aberration frequency and reduction on the rooth growth compared to negative control. Bridges and chromosome stickness were the most frequent kind of aberration in dividing cells. Furthermore, breaks were also observed. No significant increase in the number of micronuclei was found in relation to the negative controls. For Ames test were used the Salmonella typhymurium strains TA98 and TA100 without metabolic activation, applying the direct method. Prior to the Kado test, organic fractions from the water samples were obtained through XAD resin concentration. The mutagenicity organic extracts were evaluated by Kado test using TA98 and TA100 strains, in the absence and presence of S9 mix (metabolic activation). The concentrations of seven heavy metal ions were measured in water samples, but only Ni, Cu and Cr levels exceeded the permissible maximum concentration for the natural reservoirs. The results obtained for mutagenic activity using the Ames test were negative in all raw water samples analyzed. Positive results in XAD4 extracts of water samples were obtained for TA98 in the presence of S9 mix for two stations. Concentrations of heavy metals and nitrate can be correlated with the toxicity and genotoxicity of water analyzed. The mutagenic effect detected with TA98 strain suggested that organic compounds (after metabolization) are involved with the mutagenicity detected in the samples analyzed. The data set obtained in this work indicated the presence of at least two classes of mutagens: organic and inorganic compounds

Análise da toxicidade no açude Riacho da Cachoeira, Lajes Pintadas (RN): um desafio interdisciplinar

Contamination by complex mixtures of various origins has been explored and studied for decades. Radon is a naturally occurring environmental contaminant that causes carcinogenic effects. These emissions can cause mutations in the lung tissue, which can initiate a carcinogenic process. Thus the dam Creek Falls, located in the municipality of Lajes Pintadas, was chosen for the development of this study, since cancer rates in the region reach 9% of the population annually, with this, the main objective of this study was evaluate the mutagenicity and toxicity of Riacho da Cachoeira damunder the influence of radon. The methodology ecotoxicological tests were performed with Ceriodaphinia dubia, as well as tests with Tradescantia pallida genotoxicologicos and Oreochromis niloticus. To understand how the population of Pintadas Slabs realizes the environment, we performed a study of environmental perception. The test results indicated that the reservoir water is toxic to test organimos exposed, found heavy metals, chloride, total and fecal coliforms as well as radon levels above the maximum allowed under Brazilian law. These results can be justified because it is so complex samples composed of different compounds that interact only with each other or causing synergistic effects. It was concluded that the dam Creek Waterfall, is contaminated with radon, as well as heavy metals, coliforms and chloride, causing toxic effects to the natural community. Thus, further studies should be performed with the human population of the region, to verify that the high rates of cancer in the population of the municipality may be linked to the presence of natural radiation. Thus, it is expected that the competent bodies that administer the municipality of Lajes Pintadas take reasonable steps to minimize risks and ensure the health of the community that still makes use of the weir

Avaliação do potencial mutagênico da água do açude de Lucrécia (RN- Brasil): um enfoque na relação saúde e ambiente

The water quality of many reservoirs in the world has been reduced due to percolation of contaminants to water, which can have natural or anthropogenic origin, increasing the level of genotoxic compounds in aquatic ecosystems. This fact has contributed to the reduction of environmental quality, and commitment the health of living beings that inhabit these ecosystems, including the human population. In this backdrop of reduced water quality, is the Lucrecia dam, which is a major surface water reservoirs by volume of semi-arid region of Rio Grande do Norte, and that has shown contamination by heavy metals, cyanobacteria toxic and the natural presence of Radon. The population that use this source has been showing high rates of cancer, popularly associated with the consumption of this water, with a prevalence about three times higher compared to the whole state of Rio Grande do Norte. Based on this, the present study aimed to evaluate the mutagenic potencial of surface water from the Lucrecia dam, using the Micronucleus Test in Tradescantia pallida (Trad-MN) and in human peripheral blood lymphocytes (CBMN) assay, as well as identify the concentrations of some heavy metals in this water. Water samples were collected on a dry season and a rainy season, in two distinct points. Moreover, in order to bring a completely view about the relationship of man-health-environment in this local, through the knowledge of knowing / acting environmental from residents of Lucrecia, and the use and perceptions they have about the dam of your city, a study of Environmental Perception was carried out with local residents. The results obtained for the both micronucleus test, showed significant results for the three points analyzed. The strongest mutagenic effect was observed in the dry season for both assays. Chemical analyses detected an increase of heavy metal levels in different points and season above the maximum allowed by legislation. Regarding the study of Environmental Perception with local residents, it was observed the knowledge of the environment that the residents have, as well as the strong ties and perceptions with the dam of the city. Thus, the combination of these two aspects (the genetic toxicity tests conducted in the dam together with analysis of environmental perception with the residents of Lucrecia) allowed to draw a more complete diagnosis on the local situation

Metais pesados no caranguejo Ucides cordatus (Linnaeus, 1763) e ecotoxicologia de sedimentos do estuario dos Rios Jundiai e Potengi - RN

This study is conducted in the estuary of the rivers Jundiaí and Potengi, one of the most important estuaries of Rio Grande do Norte, which suffers a strong anthropogenic influence from neighboring cities. According to Resolution 344/2005 environments that have high concentrations of metals such as arsenic, cadmium, lead and mercury need ecotoxicological tests. This study aims to evaluate the heavy metals contamination in the estuary through analysis of sediment collected at four points distributed from Macaíba to Natal city, and in the crab Uçá, Ucides cordatus. The study aims also to evaluate the effects of sediment toxicity in the tests organisms Leptocheirus plumulosus. To obtain data about the concentrations of heavy metals in the environment, sediments were collected in January and May 2011 and crab Uçá was collected in June 2011. On the other hand the monitoring was carried out through toxicological tests with sediment collected from July to October 2011. During the collection of sediment samples the physico-chemical parameters of water (dissolved oxygen, pH, chloride, turbidity, conductivity and temperature) were measured by using multi-parametric probe (TROLL 9500). It was possible to identify contamination by metals such as lead, cadmium, arsenic and copper both in the sediment and in the Uçá crab, which characterizes that the consumption of this crustacean may be a risk to human health. Once the concentrations of metals were identified, toxicology tests were performed and revealed toxic effect to organisms in at least one of the four months studied. Point 2 was classified as toxic in three of the four months studied . The heavy metal contamination is a risk to the environment, to aquatic organisms and to the community which survives of resources taken from the environment