937 resultados para co-produced water


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While most animal–bacterial symbioses are reestablished each successive generation, the mechanisms by which the host and its potential microbial partners ensure tissue colonization remain largely undescribed. We used the model association between the squid Euprymna scolopes and Vibrio fischeri to examine this process. This light organ symbiosis is initiated when V. fischeri cells present in the surrounding seawater enter pores on the surface of the nascent organ and colonize deep epithelia-lined crypts. We discovered that when newly hatched squid were experimentally exposed to natural seawater, the animals responded by secreting a viscous material from the pores of the organ. Animals maintained in filtered seawater produced no secretions unless Gram-negative bacteria, either living or dead, were reintroduced. The viscous material bound only lectins that are specific for either N-acetylneuraminic acid or N-acetylgalactosamine, suggesting that it was composed of a mucus-containing matrix. Complex ciliated fields on the surface of the organ produced water currents that focused the matrix into a mass that was tethered to, and suspended above, the light organ pores. When V. fischeri cells were introduced into the seawater surrounding the squid, the bacteria were drawn into its fluid-filled body cavity during ventilation and were captured in the matrix. After residing as an aggregate for several hours, the symbionts migrated into the pores and colonized the crypt epithelia. This mode of infection may be an example of a widespread strategy by which aquatic hosts increase the likelihood of successful colonization by rarely encountered symbionts.

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Thesis (Ph.D.)--University of Washington, 2016-06

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Rare earth element and yttrium (REE+Y) concentrations were determined in 49 Late Devonian reefal carbonates from the Lennard Shelf, Canning Basin, Western Australia. Shale-normalized (SN) REE+Y patterns of the Late Devonian samples display features consistent with the geochemistry of well-oxygenated, shallow seawater. A variety of different ancient limestone components, including microbialites, some skeletal carbonates (stromatoporoids), and cements, record seawater-like REE+Y signatures. Contamination associated with phosphate, Fe-oxides and shale was tested quantitatively, and can be discounted as the source of the REE+Y patterns. Co-occurring carbonate components that presumably precipitated from the same seawater have different relative REE concentrations, but consistent REE+Y patterns. Clean Devonian early marine cements (n = 3) display REE+Y signatures most like that of modern open ocean seawater and the highest Y/Ho ratios (e.g., 59) and greatest light REE (LREE) depletion (average Nd-SN/Yb-SN = 0.413, SD = 0.076). However, synsedimentary cements have the lowest REE concentrations (e.g., 405 ppb). Non-contaminated Devonian microbialite samples containing a mixture of the calcimicrobe Renalcis and micritic thrombolite aggregates in early marine cement (n = 11) have the highest relative REE concentrations of tested carbonates (average total REE = 11.3 ppm). Stromatoporoid skeletons, unlike modern corals, algae and molluscs, also contain well-developed, seawater-like REE patterns. Samples from an estuarine fringing reef have very different REE+Y patterns with LREE enrichment (Nd-SN/Yb-SN > 1), possibly reflecting inclusion of estuarine colloidal material that contained preferentially scavenged LREE from a nearby riverine input source. Hence, Devonian limestones provide a proxy for marine REE geochemistry and allow the differentiation of co-occurring water masses on the ancient Lennard Shelf. Although appropriate partition coefficients for quantification of Devonian seawater REE concentrations from out data are unknown, hypothetical Devonian Canning Basin seawater REE patterns were obtained with coefficients derived from modern natural proxies and experimental values. Resulting Devonian seawater patterns are slightly enriched in LREE compared to most modem seawaters and suggest higher overall REE concentrations, but are very similar to seawaters from regions with high terrigenous inputs. Our results suggest that most limestones should record important aspects of the REE geochemistry of the waters in which they precipitated, provided they are relatively free of terrigenous contamination and major diagenetic alteration from fluids with high, non-seawater-like REE contents. Hence, we expect that many other ancient limestones will serve as seawater REE proxies, and thereby provide information on paleoceanography, paleogeography and geochemical evolution of the oceans. Copyright (C) 2004 Elsevier Ltd.

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Reperfusion-induced ventricular fibrillation (VF) severely threatens the lives of post-myocardial infarction patients. Carbon monoxide (CO) - produced by haem oxygenase in cardiomyocytes - has been reported to prevent VF through an unknown mechanism of action. Here, we report that CO prolongs action potential duration (APD) by inhibiting a subset of inward-rectifying potassium (Kir) channels. We show that CO blocks Kir2.2 and Kir2.3 but not Kir2.1 channels in both cardiomyocytes and HEK-293 cells transfected with Kir. CO directly inhibits Kir2.3 by interfering with its interaction with the second messenger phosphatidylinositol (4,5)-bisphosphate (PIP 2). As the inhibition of Kir2.2 and Kir2.3 by CO prolongs APD in myocytes, cardiac Kir2.2 and Kir2.3 are promising targets for the prevention of reperfusion-induced VF. © 2014 Macmillan Publishers Limited. All rights reserved.

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The principal effluent in the oil industry is the produced water, which is commonly associated to the produced oil. It presents a pronounced volume of production and it can be reflected on the environment and society, if its discharge is unappropriated. Therefore, it is indispensable a valuable careful to establish and maintain its management. The traditional treatment of produced water, usualy includes both tecniques, flocculation and flotation. At flocculation processes, there are traditional floculant agents that aren’t well specified by tecnichal information tables and still expensive. As for the flotation process, it’s the step in which is possible to separate the suspended particles in the effluent. The dissolved air flotation (DAF) is a technique that has been consolidating economically and environmentally, presenting great reliability when compared with other processes. The DAF is presented as a process widely used in various fields of water and wastewater treatment around the globe. In this regard, this study was aimed to evaluate the potential of an alternative natural flocculant agent based on Moringa oleifera to reduce the amount of oil and grease (TOG) in produced water from the oil industry by the method of flocculation/DAF. the natural flocculant agent was evaluated by its efficacy, as well as its efficiency when compared with two commercial flocculant agents normally used by the petroleum industry. The experiments were conducted following an experimental design and the overall efficiencies for all flocculants were treated through statistical calculation based on the use of STATISTICA software version 10.0. Therefore, contour surfaces were obtained from the experimental design and were interpreted in terms of the response variable removal efficiency TOG (total oil and greases). The plan still allowed to obtain mathematical models for calculating the response variable in the studied conditions. Commercial flocculants showed similar behavior, with an average overall efficiency of 90% for oil removal, however it is the economical analysis the decisive factor to choose one of these flocculant agents to the process. The natural alternative flocculant agent based on Moringa oleifera showed lower separation efficiency than those of commercials one (average 70%), on the other hand this flocculant causes less environmental impacts and it´s less expensive

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Primary processing of natural gas platforms as Mexilhão Field (PMXL-1 ) in the Santos Basin, where monoethylene glycol (MEG) has been used to inhibit the formation of hydrates, present operational problems caused by salt scale in the recovery unit of MEG. Bibliographic search and data analysis of salt solubility in mixed solvents, namely water and MEG, indicate that experimental reports are available to a relatively restricted number of ionic species present in the produced water, such as NaCl and KCl. The aim of this study was to develop a method for calculating of salt solubilities in mixed solvent mixtures, in explantion, NaCl or KCl in aqueous mixtures of MEG. The method of calculating extend the Pitzer model, with the approach Lorimer, for aqueous systems containing a salt and another solvent (MEG). Python language in the Integrated Development Environment (IDE) Eclipse was used in the creation of the computational applications. The results indicate the feasibility of the proposed calculation method for a systematic series of salt (NaCl or KCl) solubility data in aqueous mixtures of MEG at various temperatures. Moreover, the application of the developed tool in Python has proven to be suitable for parameter estimation and simulation purposes

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Produced water is a major problem associated with the crude oil extraction activity. The monitoring of the levels of metals in the waste is constant and requires the use of sensitive analytical techniques. However, the determination of trace elements can often require a pre-concentration step. The objective of this study was to develop a simple and rapid analytical method for the extraction and pre-concentration based on extraction phenomenon cloud point for the determination of Cd, Pb and Tl in produced water samples by spectrometry of high resolution Absorption source continues and atomization graphite furnace. The Box Behnken design was used to obtain the optimal condition of extraction of analytes. The factors were evaluated: concentration of complexing agent (o,o-dietilditilfosfato ammonium, DDTP), the concentration of hydrochloric acid and concentration of surfactant (Triton X -114). The optimal condition obtained through extraction was: 0,6% m v-1 DDTP, HCl 0,3 mol L-1 and 0,2% m v-1 of Triton X - 114 for Pb; 0,7% m v-1 DDTP, HCl 0,8 mol L-1 and 0,2% m v-1 Triton X-114 for Cd. For Tl was evidenced that best extraction condition occurs with no DDTP, the extraction conditions were HCl 1,0 mol L-1 e 1,0% m v-1 de Triton X - 114. The limits of detection for the proposed method were 0,005 µg L-1 , 0,03 µg L-1 and 0,09 µg L-1 to Cd, Pb and Tl, Respectively. Enrichment factors Were greater than 10 times. The method was applied to the water produced in the Potiguar basin, and addition and recovery tests were performed, and values were between 81% and 120%. The precision was expressed with relative standard deviation (RSD) is less than 5%

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Drilling fluids have fundamental importance in the petroleum activities, since they are responsible for remove the cuttings, maintain pressure and well stability, preventing collapse and inflow of fluid into the rock formation and maintain lubrication and cooling the drill. There are basically three types of drilling fluids: water-based, non-aqueous and aerated based. The water-based drilling fluid is widely used because it is less aggressive to the environment and provide excellent stability and inhibition (when the water based drilling fluid is a inhibition fluid), among other qualities. Produced water is generated simultaneously with oil during production and has high concentrations of metals and contaminants, so it’s necessary to treat for disposal this water. The produced water from the fields of Urucu-AM and Riacho da forquilha-RN have high concentrations of contaminants, metals and salts such as calcium and magnesium, complicating their treatment and disposal. Thus, the objective was to analyze the use of synthetic produced water with similar characteristics of produced water from Urucu-AM and Riacho da Forquilha-RN for formulate a water-based drilling mud, noting the influence of varying the concentration of calcium and magnesium into filtered and rheology tests. We conducted a simple 32 factorial experimental design for statistical modeling of data. The results showed that the varying concentrations of calcium and magnesium did not influence the rheology of the fluid, where in the plastic viscosity, apparent viscosity and the initial and final gels does not varied significantly. For the filtrate tests, calcium concentration in a linear fashion influenced chloride concentration, where when we have a higher concentration of calcium we have a higher the concentration of chloride in the filtrate. For the Urucu’s produced water based fluids, volume of filtrate was observed that the calcium concentration influences quadratically, this means that high calcium concentrations interfere with the power of the inhibitors used in the formulation of the filtered fluid. For Riacho’s produced water based fluid, Calcium’s influences is linear for volume of filtrate. The magnesium concentration was significant only for chloride concentration in a quadratic way just for Urucu’s produced water based fluids. The mud with maximum concentration of magnesium (9,411g/L), but minimal concentration of calcium (0,733g/L) showed good results. Therefore, a maximum water produced by magnesium concentration of 9,411g/L and the maximum calcium concentration of 0,733g/L can be used for formulating water-based drilling fluids, providing appropriate properties for this kind of fluid.

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In this work, the treatment of wastewater from the textile industry, containing dyes as Yellow Novacron (YN), Red Remazol BR (RRB) and Blue Novacron CD (NB), and also, the treatment of wastewater from petrochemical industry (produced water) were investigated by anodic oxidation (OA) with platinum anodes supported on titanium (Ti/Pt) and boron-doped diamond (DDB). Definitely, one of the main parameters of this kind of treatment is the type of electrocatalytic material used, since the mechanisms and products of some anodic reactions depend on it. The OA of synthetic effluents containing with RRB, NB and YN were investigated in order to find the best conditions for the removal of color and organic content of the dye. According to the experimental results, the process of OA is suitable for decolorization of wastewaters containing these textile dyes due to electrocatalytic properties of DDB and Pt anodes. Removal of the organic load was more efficient at DDB, in all cases; where the dyes were degraded to aliphatic carboxylic acids at the end of the electrolysis. Energy requirements for the removal of color during OA of solutions of RRB, NB and YN depends mainly on the operating conditions, for example, RRB passes of 3.30 kWh m-3 at 20 mA cm-2 for 4.28 kWh m-3 at 60 mA cm-2 (pH = 1); 15.23 kWh m-3 at 20 mA cm-2 to 24.75 kWh m-3 at 60 mA cm-2 (pH 4.5); 10.80 kWh m-3 at 20 mA cm-2 to 31.5 kWh m-3 at 60 mA cm-2 (pH = 8) (estimated data for volume of treated effluent). On the other hand, in the study of OA of produced water effluent generated by petrochemical industry, galvanostatic electrolysis using DDB led to the complete removal of COD (98%), due to large amounts of hydroxyl radicals and peroxodisulphates generated from the oxidation of water and sulfates in solution, respectively. Thus, the rate of COD removal increases with increasing applied current density (15-60 mAcm-2 ). Moreover, at Pt electrode, approximately 50% removal of the organic load was achieved by applying from 15 to 30 mAcm-2 while 80% of COD removal was achieved for 60 mAcm-2 . Thus, the results obtained in the application of this technology were satisfactory depending on the electrocatalytic materials and operating conditions used for removal of organic load (petrochemical and textile effluents) as well as for the removal of color (in the case of textile effluents). Therefore, the applicability of electrochemical treatment can be considered as a new alternative like pretreatment or treatment of effluents derived from textiles and petrochemical industries.

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Produced water is considered the main effluent of the oil industry, due to their increased volume in mature fields and its varied composition. The oil and grease content (TOG) is the main parameter for the final disposal of produced water. In this context, it is of great significance to develop an alternative method based on guar gum gel for the treatment of synthetic produced water, and using as the differential a polymer having high hydrophilicity for clarifying waters contaminated with oil. Thus, this study aims to evaluate the efficiency of guar gum gels in the remotion of oil from produced water. Guar gum is a natural polymer that, under specific conditions, forms three-dimensional structures, with important physical and chemical properties. By crosslinking the polymer chains by borate ions in the presence of salts, the effect salting out occurs, reducing the solubility of the polymer gel in water. As a result, there is phase separation with the oil trapped in the collapsed gel. The TOG was quantified from the spectroscopy in the ultraviolet and visible region. The system was proven to be highly efficient in the removal of dispersed oil from water produced synthetically, reaching removal percentages above 90%.

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The produce of waste and the amount of the water produced coming from activities of petroleum production and extraction has been a biggest challenge for oil companies with respect to environmental compliance due to toxicity. The discard or the reuse this effluent containing organic compounds as BTEX (benzene, toluene, ethylbenzene and xylene) can cause serious environmental and human health problems. Thus, the objective this paper was study the performance of two process (separately and sequential) in one synthetic effluent for the benzene, toluene and xylene removal (volatile hydrocarbons presents in the produced water) through of electrochemical treatment using Ti/Pt electrode and exchange resin ionic used in the adsorption process. The synthetic solution of BTX was prepared with concentration of 22,8 mg L-1, 9,7 mg L-1 e 9,0 mg L-1, respectively, in Na2SO4 0,1 mol L-1. The experiments was developed in batch with 0.3 L of solution at 25ºC. The electrochemical oxidation process was accomplished with a Ti/Pt electrode with different current density (J = 10, 20 e 30 mA.cm-2). In the adsorption process, we used an ionic exchange resin (Purolite MB 478), using different amounts of mass (2,5, 5 and 10 g). To verify the process of technics in the sequential treatment, was fixed the current density at 10 mA cm-2 and the resin weight was 2.5 g. Analysis of UV-VIS spectrophotometry, chemical oxygen demand (COD) and gas chromatography with selective photoionization detector (PID) and flame ionization (FID), confirmed the high efficiency in the removal of organic compounds after treatment. It was found that the electrochemical process (separate and sequential) is more efficient than absorption, reaching values of COD removal exceeding 70%, confirmed by the study of the cyclic voltammetry and polarization curves. While the adsorption (separately), the COD removal did not exceed 25,8%, due to interactions resin. However, the sequential process (electrochemical oxidation and adsorption) proved to be a suitable alternative, efficient and cost-effectiveness for the treatment of effluents petrochemical.

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Structure, energetics and reactions of ions in the gas phase can be revealed by mass spectrometry techniques coupled to ions activation methods. Ions can gain enough energy for dissociation by absorbing IR light photons introduced by an IR laser to the mass spectrometer. Also collisions with a neutral molecule can increase the internal energy of ions and provide the dissociation threshold energy. Infrared multiple photon dissociation (IRMPD) or sustained off-resonance irradiation collision-induced dissociation (SORI-CID) methods are combined with Fourier Transform Ion Cyclotron Resonance (FT-ICR) mass spectrometers where ions can be held at low pressures for a long time. The outcome of ion activation techniques especially when it is compared to the computational methods results is of great importance since it provides useful information about the structure, thermochemistry and reactivity of ions of interest. In this work structure, energetics and reactivity of metal cation complexes with dipeptides are investigated. Effect of metal cation size and charge as well as microsolvation on the structure of these complexes has been studied. Structures of bare and hydrated Na and Ca complexes with isomeric dipeptides AlaGly and GlyAla are characterized by means of IRMPD spectroscopy and computational methods. At the second step unimolecular dissociation reactions of singly charged and doubly charged multimetallic complexes of alkaline earth metal cations with GlyGly are examined by CID method. Also structural features of these complexes are revealed by comparing their IRMPD spectra with calculated IR spectra of possible structures. At last the unimolecular dissociation reactions of Mn complexes are studied. IRMPD spectroscopy along with computational methods is also employed for structural elucidation of Mn complexes. In addition the ion-molecule reactions of Mn complexes with CO and water are explored in the low pressures obtained in the ICR cell.

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Advances in digital photography and distribution technologies enable many people to produce and distribute images of their sex acts. When teenagers do this, the photos and videos they create can be legally classified as child pornography since the law makes no exception for youth who create sexually explicit images of themselves. The dominant discussions about teenage girls producing sexually explicit media (including sexting) are profoundly unproductive: (1) they blame teenage girls for creating private images that another person later maliciously distributed and (2) they fail to respect—or even discuss—teenagers’ rights to freedom of expression. Cell phones and the internet make producing and distributing images extremely easy, which provide widely accessible venues for both consensual sexual expression between partners and for sexual harassment. Dominant understandings view sexting as a troubling teenage trend created through the combination of camera phones and adolescent hormones and impulsivity, but this view often conflates consensual sexting between partners with the malicious distribution of a person’s private image as essentially equivalent behaviors. In this project, I ask: What is the role of assumptions about teen girls’ sexual agency in these problematic understandings of sexting that blame victims and deny teenagers’ rights? In contrast to the popular media panic about online predators and the familiar accusation that youth are wasting their leisure time by using digital media, some people champion the internet as a democratic space that offers young people the opportunity to explore identities and develop social and communication skills. Yet, when teen girls’ sexuality enters this conversation, all this debate and discussion narrows to a problematic consensus. The optimists about adolescents and technology fall silent, and the argument that media production is inherently empowering for girls does not seem to apply to a girl who produces a sexually explicit image of herself. Instead, feminist, popular, and legal commentaries assert that she is necessarily a victim: of a “sexualized” mass media, pressure from her male peers, digital technology, her brain structures or hormones, or her own low self-esteem and misplaced desire for attention. Why and how are teenage girls’ sexual choices produced as evidence of their failure or success in achieving Western liberal ideals of self-esteem, resistance, and agency? Since mass media and policy reactions to sexting have so far been overwhelmingly sexist and counter-productive, it is crucial to interrogate the concepts and assumptions that characterize mainstream understandings of sexting. I argue that the common sense that is co-produced by law and mass media underlies the problematic legal and policy responses to sexting. Analyzing a range of nonfiction texts including newspaper articles, talk shows, press releases, public service announcements, websites, legislative debates, and legal documents, I investigate gendered, racialized, age-based, and technologically determinist common sense assumptions about teenage girls’ sexual agency. I examine the consensus and continuities that exist between news, nonfiction mass media, policy, institutions, and law, and describe the limits of their debates. I find that this early 21st century post-feminist girl-power moment not only demands that girls live up to gendered sexual ideals but also insists that actively choosing to follow these norms is the only way to exercise sexual agency. This is the first study to date examining the relationship of conventional wisdom about digital media and teenage girls’ sexuality to both policy and mass media.

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The oil production in Brazil has been increasing each year. Consequently, increasing volumes of water produced are generated with large quantities of contaminants, which brings many problems in disposing of these waters. The concern that the concentrations of contaminants in water produced meet existing laws for disposal of effluents, has been extremely important for the development of different techniques for treatment of water produced. The study of clay minerals as adsorbents of organic contaminants has grown considerably so in order to combine the low cost with the efficiency of environmental preservation and health issues. Thus, this study aims to understand the characteristics of vermiculite clay, sodium bentonite, calcium bentonite and diatomite and evaluate their performance as adsorbents for phenol in the water produced. Through adsorption isotherms it was possible to observe the behavior of these adsorptive clay and diatomite for adsorption of phenol, the main phenolic compound found in water produced. Different concentrations of synthetic solutions of phenol were put in touch with these adsorbents under same conditions of agitation and temperature. The adsorbents were composted adsorptive favorable, but the vermiculite and diatomite showed little capacity for absorption, being suggested for absorbs small concentrations of phenol in the balance isothermal

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The production of water has become one of the most important wastes in the petroleum industry, specifically in the up stream segment. The treatment of this kind of effluents is complex and normally requires high costs. In this context, the electrochemical treatment emerges as an alternative methodology for treating the wastewaters. It employs electrochemical reactions to increase the capability and efficiency of the traditional chemical treatments for associated produced water. The use of electrochemical reactors can be effective with small changes in traditional treatments, generally not representing a significant additional surface area for new equipments (due to the high cost of square meter on offshore platforms) and also it can use almost the same equipments, in continuous or batch flow, without others high costs investments. Electrochemical treatment causes low environmental impact, because the process uses electrons as reagent and generates small amount of wastes. In this work, it was studied two types of electrochemical reactors: eletroflocculation and eletroflotation, with the aim of removing of Cu2+, Zn2+, phenol and BTEX mixture of produced water. In eletroflocculation, an electrical potential was applied to an aqueous solution containing NaCl. For this, it was used iron electrodes, which promote the dissolution of metal ions, generating Fe2+ and gases which, in appropriate pH, promote also clotting-flocculation reactions, removing Cu2+ and Zn2+. In eletroflotation, a carbon steel cathode and a DSA type anode (Ti/TiO2-RuO2-SnO2) were used in a NaCl solution. It was applied an electrical current, producing strong oxidant agents as Cl2 and HOCl, increasing the degradation rate of BTEX and phenol. Under different flow rates, the Zn2+ was removed by electrodeposition or by ZnOH formation, due the increasing of pH during the reaction. To better understand the electrochemical process, a statistical protocol factor (22) with central point was conducted to analyze the sensitivity of operating parameters on removing Zn2+ by eletroflotation, confirming that the current density affected the process negatively and the flow rate positively. For economical viability of these two electrochemical treatments, the energy consumption was calculated, taking in account the kWh given by ANEEL. The treatment cost obtained were quite attractive in comparison with the current treatments used in Rio Grande do Norte state. In addition, it could still be reduced for the case of using other alternative energy source such as solar, wind or gas generated directly from the Petrochemical Plant or offshore platforms