Adição de poliuretana em pastas de cimento para poços de petróleo como agente de correção do filtrado

Chemical admixtures, when properly selected and quantified, play an important role in obtaining adequate slurry systems for quality primary cementing operations. They assure the proper operation of a well and reduce costs attributed to corrective cementing jobs. Controlling the amount lost by filtering through the slurry to permeable areas is one of the most important requirements in an operation, commonly controlled by chemical admixtures, such as carboxymethylcellulose (CMC). However, problems related to temperature, salttolerance and the secundary retarding effect are commonly reported in the literature. According to the scenario described above, the use of an aqueous dispersion of non-ionic poliurethane was proposed to control the filter loss, given its low ionic interaction with the free ions present in the slurries in humid state. Therefore, this study aims at assessing the efficiency of poliurethane to reduce filter loss in different temperature and pressure conditions as well as the synergistic effect with other admixtures. The temperatures and pressures used in laboratory tests simulate the same conditions of oil wells with depths of 500 to 1200 m. The poliurethane showed resistance to thermal degradation and stability in the presence of salts. With the increase in the concentration of the polymer there was a considerable decrease in the volume lost by filtration, and this has been effective even with the increase in temperature

Influência da adição de gres porcelanato no comportamento mecânico e microestrutural em pastas de cimento portland para cimentação de poços de petróleo

Cementation operation consists in an extremely important work for the phases of perforation and completion of oil wells, causing a great impact on the well productivity. Several problems can occur with the cement during the primary cementation, as well as throughout the productive period. The corrective operations are frequent, but they are expensive and demands production time. Besides the direct cost, prejudices from the interruption of oil and gas production till the implementation of a corrective operation must be also taken into account. The purpose of this work is the development of an alternative cement paste constituted of Portland cement and porcelainized stoneware residue produced by ceramic industry in order to achieve characteristics as low permeability, high tenacity, and high mechanical resistance, capable of supporting various operations as production or oil wells recuperation. Four different concentration measures of hydrated paste were evaluated: a reference paste, and three additional ones with ceramic residue in concentrations of the order of 10%, 20% and 30% in relation to cement dough. High resistance and low permeability were found in high concentration of residues, as well as it was proved the pozolanic reactivity of the residue in relation to Portland cement, which was characterized through x-ray and thermogravimetry assays. It was evident the decrease of calcium hydroxide content, once it was substituted by formation of new hydrated products as it was added ceramic residue

Investigação e gerenciamento de áreas contaminadas por postos revendedores de combustíveis em Natal

Activities that have fuel subterranean storage system are considered potentially polluting fuels by CONAMA Resolution 273, due to the possibility of leak, outpouring and overflow of fuel into the ground. Being even more worrying when contaminate groundwater for public supply, as the case of Natal City. For this reason, the Public Ministry/RN, in partnership with UFRN, developed the project environmental suitability of Gas stations in Natal, of which 36% showed evidence of contamination. This paper describes the four stages of the management of contaminated areas: preliminary assessment of environmental liabilities, detailed confirmatory investigation of the contamination, risk analysis to human health (RBCA), as well as the remediation plan of degraded areas. Therefore it is presented a case study. For the area investigated has been proposed a mathematical method to estimate the volume of LNAPL by a free CAD software (ScketchUp) and compare it with the partition method for grid area. Were also performed 3D graphics designs of feathers contamination. Research results showed that passive benzene contamination in groundwater was 2791.77 μg/L, when the maximum allowed by CONAMA Resolution 420 is 5 μg/L which is the potability standards. The individual and cumulative risks were calculated from 4.4 x10-3, both above the limits of 1.0 x10-5 or by RBCA 1.0 x10-6 by the Public Ministry/RN. Corrective action points that remediation of dissolved phase benzene is expected to reach a concentration of 25 μg/L, based on carcinogenic risk for ingestion of groundwater by residents residential, diverging legislation. According to the proposed model, the volume of LNAPL using the ScketchUp was 17.59 m3, while by the grid partitioning method was 14.02 m3. Because of the low recovery, the expected removal of LNAPL is 11 years, if the multiphase extraction system installed in the enterprise is not optimized

OBALUAIÊ: um estudo sobre o estigma no convívio com o HIV/Aids em terreiros de Umbanda na cidade de Fortaleza-Ceará

The tradition and living in African-Brazilian religious spaces, called yards, reveal how dynamic the reproduction and exchange of knowledge are, and that through their worldview, reveal ways of dealing with health and disease. The yards are culturally rich territories, in which people shape concepts, practices, and beliefs about health, disease and forms of healing, passed on from generation to generation through oral tradition. With the advent of HIV/AIDS from the 80s, a new challenge is established in the community of the yards and in the individual trajectories of people affected by the disease, who since an early age participate in this religious practice. The objective of this research is the analysis on the stigma in living with HIV/AIDS in yards of Umbanda in Fortaleza-Ceará, considering the (re)production of social dramas experienced by the community in question. During the investigation we adopted two basic parameters: the first one considers the understanding of the reproduction of stigma (or deteriorated identity) in relation to HIV/AIDS in its socio-historical dimension and its effects in the investigated context (Goffman, 1988). And the second one refers to the creation and reproduction of social dramas as a social experience carried through learning, handling and symbolic performance, which is reproduced in four stages: rupture, crisis, corrective action and reintegration (Turner, 1971)

A tutela constitucional da exploração de petróleo em águas internacionais em face do princípio do desenvolvimento sustentável: a possibilidade de responsabilização civil do dano futuro

The demands brought by a society doomed to the constant production of global risks, which whose effects are not immediately noticed effects are not perceived immediately, claim from the Law a new Theory about the Risk, that would offer a broad environmental protection, at the same time it would still be compatible with the idea of economic efficiency, required by the Modern Industry. The expansion of the methods and technologies regarding the exploitation and production of oil causes the constant expansion of the exploitable boundaries, especially in ultra-deep waters with the Pre-salt layer, in Brazil, or the still incipient research about the polymetallic nodules and other mineral sources in international waters, like the Atlântico Sudoeste, by the Programme on Ocean Science in Relation do Non Living Resources (OSNLR), a global study performed in partnership with the Intergovernmental Oceanographic Commission, from UNESCO (IOC UNESCO) and also with the Division of Ocean Affairs and Law of the Sea (UNDOALOS). Thus, we aim to analyze the correlation, and possible collisions between the right to a balanced environment and the free exercise of economic activity and the occurrence of environmental damages from the perspective of the exploitation activities of oil and other natural resources in international waters, specifically in the Area, from the constitutional principle of sustainable development and its legitimacy by the environmental international protection. Therefore, this study also aims to evaluate the legal framework for exploration and production of oil in international waters, particularly in the Area, and appraise how the constitutional instruments and mechanisms for environmental protection can impact on the international environmental protection system in order to ensure the present and future generations an ecologically balanced environment, laid down in Article 225 of the Brazilian Constitution, even with so many risks posed by the activities of exploitation and production of oil in international waters. In the meantime, we intend to also intend to investigate the possibility of future liability for environmental damage in order to ensure that constitutional principle and, consequently, and try to define the concept of environmental damage and its implications on the constitutional principle of environmental protection. Given all that was in summary, this work aims to contribute to the evolution of the new Theory of Environmental Risk, turning the law into something more than a punitive or corrective element in this society, but into a legal risk management, that may be triggered even before the consolidation of the damage

Contribuição ao estudo da isonomia na tributação sob a perspectiva da ordem econômica

The study aims to investigate the limits of state intervention via induction on Economic Order, especially in cases regarding tax equality, through the analysis of their effects on economic development and on free competition from the perspective of economic efficiency and the Constitution. Thus, the work seeks to demonstrate that the achievement of equality in taxation is important in that it strengthens the economic relations in terms of efficiency, protects competition and fosters economic development to reduce regional and social inequalities and other constitutional desiderata. A dissertation is characterized by interdisciplinarity and was divided into two parts. The first is to discuss the legal meaning of equality from the doctrinal analysis of the principle and the relationship between equality and justice in the economic sense without rejecting its philosophical content. It is noteworthy that hermeneutics and the philosophy of language are useful tools for achieving equality in presenting the pragmatic methodologies applicable to the subject in terms of corrective justice. Based on these general assumptions, is going to study the tax equality and their characteristics, the corollary of the ability to pay and its relation to the economic capacity and the issue of progressivity in taxation as an ideal of distributive justice. The second part concerns the legal foundations of Economic Order and its relation to extrafiscality as a means of economic regulation in order to investigate the efficiency of this induction in order to promote economic development, free competition and tax equality itself to reduce inequalities and distributing wealth. Within this context, we investigated the scope of the constitutional principles of economic order, free enterprise and free competition, and favored differential treatment for small and medium enterprises, the issue of regional development for the reduction of regional and social inequalities, the problem the "fiscal war" and finally the efficiency from the perspective of Economic Analysis of Law

Conhecimento do enfermeiro sobre as ações de vigilância epidemiológica no Hospital Universitário Onofre Lopes, Natal, RN

This is an exploratory descriptive study with quantitative approach, aiming to verify the nurses' knowledge concerning the epidemiological surveillance activities at the Onofre Lopes hospital (HUOL), in Natal, Rio Grande do Norte. The study was performed with 63 nurses from the hospital and the data were collected through a questionnaire. All data were analyzed using descriptive statistics. The results were discussed and organized into four sections: nurses' knowledge on hospital epidemiological surveillance; procedures of the professional nurse through compulsory notification diseases; difficulties found by nurses to register the compulsory notification diseases and suggestions of strategies to joint epidemiological surveillance service with the care practices of nurses. The results showed that 55.55% of nurses know the main action of epidemiological surveillance, compulsory notification of diseases, and that 42.86% reported to the Hospital Epidemiology Center , while 57.14% did not allocate the information for this service. Most nurses found it difficult to perform notification for not knowing its flow; for the surveillance service does not operate 24 hours and for vagueness on diagnostic of disorders. Suggestions of strategies to improve the quality of epidemiological information are focused on training of nurses in hospital epidemiological surveillance; working in partnership with the surveillance center; diffusion of information on surveillance and conducting a daily active search. It comes to conclusion that most nurses don't notify the Surveillance Center about Compulsory Notification Diseases and it wasn't observed the incorporation of integrality values between the hospital surveillance and all nurses, since this principle guides the actions of health services based on dialogue, listening, ethical commitment, sharing of knowledge among professionals of various services and respect towards other professionals. Therefore, the integrality gap in the actions of the nurses studied, as well as in the surveillance service does not mobilize the potential of such services to changes in the sense of achievement of practices aimed at a special attention model that combines preventive and corrective actions, proposed and desired by SUS. Through the difficulties presented, it becomes important to recommend educational processes with strategy to transform the conducts, besides proposing actions under the principle of integrality provide responses agile and effective, as the purpose of VE hospital emergency care by the current epidemic

Desenvolvimento de um sistema de planejamento, gestão de serviços e controle de custos em obras de construção civil

The increasing competitiveness of the construction industry, set in an economic environment in which the offer is now greater than the demand , causes the prices of many products and services, are strongly influenced by the processes of production and the final consumer. Thus, to become more competitive in the market and construction companies are seeking new alternatives to reduce and control costs, production processes and tools that allow for close monitoring of the construction schedule, with the consequent compliance deadline with the client. Based on this scenario, the creation of control tools, service management and planning work emerges as an investment opportunity and an area that can promote great benefits to construction companies. The goal of this work is to present a system of planning, service management and costs control that through worksheets provide information relating to the production phase of the work, allowing the visualization of possible irregularities in the planning and cost of the enterprise, enabling the company to take steps to achieve the goals of the enterprise in question, and correct them when necessary. The developed system has been used in a piece of real estate in Rio Grande do Norte, and the results showed that its use together allowed the construction company to accompany their results and take corrective and preventive actions during the production process, efficiently and effective

Argamassas do grupo escolar Augusto Severo/RN: caracterização e incidência de manifestações patológicas

The search for cultural heritage preservation should be a constant, in order to minimize the lost of historical and cultural identity of a country. As part of this cultural heritage, highlights the importance of historical buildings. For the principles of restoration are met its important to know the state of conservation and the existing materials. Given the above, this work aims to study the pathological manifestations of the mortar coating from the Grupo Escolar Augusto Severo. For this, was conducted historical survey of the building, on-site visits with visual observation, collecting samples of mortar coating and characterization through visual and laboratory analysis, XRF, XRD, TG/DTG, OM and SEM-EDS. From the observations, pathological manifestations were found as: cracks, detachment of the coating, dirt, use of inappropriate material basis of cement, efflorescence, mold and mildew and also incompatible material base of cement. It was found that the pathological manifestations were intensified due to lack of coverage in some spots and especially the abandonment of the building, that many years does not have restoration or any other type of preventive and corrective maintenance. The results of laboratory tests indicated that the mortars studied are based on lime, with calcitic nature, and siliceous aggregate, with the presence of clay in two samples. From the samples collected, two are composed of lime, sand and clay and two by lime and sand. In this regard, it is important to conduct periodic inspections and maintenance, as well as carrying out restoration with use of material compatible with the original

Modelo de gerenciamento de estoques de peças de reposição para empresas de transporte urbano de passageiros

This work searches to offer a model to improve spare parts stock management for companies of urban passenger transport by bus, with the consequent progress in their maintenance management. Also known as MRO items (Maintenance, Repair and Operations), these spare parts, according their consumption and demand features, cost, criticity to operation, lead-time, quantity of suppliers, among other parameters, shouldn´t have managed their inventory like normal production items (work in process e final products), that because their features, are managed by more predictable models based, for example, in economic order quantity. In the case specifically of companies of urban passenger transport by bus, items MRO have significant importance in their assets and a bad management of these inventories can cause serious losses to company, leading it even bankrupticy business, in more severe situations which missing spare part provokes vehicles shutdown indefinitely. Given slight attention to the issue, which translates in little literature available about it when compared to that literature about normal items stocks, and due the fact that MRO items be critical to bus urban transport of passengers companies´, it is necessary, so, deepen in this theme searching to give technical and scientific subsidies to companies that work, in many times, empirically, with these so decisive inputs to their business. As a typical portfolio problem, in which there are n items, separated into critical and noncritical, while competing for the same resource, it was developed a new algorithm to aid in a better inventory management of spare parts used only in corrective maintenance (whose failures are unpredictable and random), by analyzing the cost-benefit ratio, which compares the level of service versus cost of each item. The model was tested in a company of urban passenger transport by bus from the city of Natal, who anonymously provided their real data to application in this work

Dedução de Funções de Alívio para Priorização de Variantes de Chaveamento Adequadas à Eliminação de Sobrecargas

Eventually, violations of voltage limits at buses or admissible loadings of transmission lines and/or power transformers may occur by the power system operation. If violations are detected in the supervision process, corrective measures may be carried out in order to eliminate them or to reduce their intensity. Loading restriction is an extreme solution and should only be adopted as the last control action. Previous researches have shown that it is possible to control constraints in electrical systems by changing the network topology, using the technique named Corrective Switching, which requires no additional costs. In previous works, the proposed calculations for verifying the ability of a switching variant in eliminating an overload in a specific branch were based on network reduction or heuristic analysis. The purpose of this work is to develop analytical derivation of linear equations to estimate current changes in a specific branch (due to switching measures) by means of few calculations. For bus-bar coupling, derivations will be based on short-circuit theory and Relief Function methodology. For bus-bar splitting, a Relief Function will be derived based on a technique of equivalent circuit. Although systems of linear equations are used to substantiate deductions, its formal solution for each variant, in real time does not become necessary. A priority list of promising variants is then assigned for final check by an exact load flow calculation and a transient analysis using ATP Alternative Transient Program. At last, results obtained by simulation in networks with different features will be presented

Sistema para detecção e diagnóstico de falhas em motores elétricos de indução utilizando lógica fuzzy

Induction motors are one of the most important equipment of modern industry. However, in many situations, are subject to inadequate conditions as high temperatures and pressures, load variations and constant vibrations, for example. Such conditions, leaving them more susceptible to failures, either external or internal in nature, unwanted in the industrial process. In this context, predictive maintenance plays an important role, where the detection and diagnosis of faults in a timely manner enables the increase of time of the engine and the possibiity of reducing costs, caused mainly by stopping the production and corrective maintenance the motor itself. In this juncture, this work proposes the design of a system that is able to detect and diagnose faults in induction motors, from the collection of electrical line voltage and current, and also the measurement of engine speed. This information will use as input to a fuzzy inference system based on rules that find and classify a failure from the variation of thess quantities

Desenvolvimento de um protocolo de comunicação para automação de subestações móveis via satélite

One of the most important decisions to turn a substation automatic and no attended it relates to the communication media between this substation and Operation Center. Generally energy companies uses radio or optic fiber, depending of distances and infrastructure of each situation. This rule applies to common substations. Mobile substations are a particular case, therefore they are conceived for use at provisional situations, emergencies, preventive or corrective maintenance. Thus the telecommunication solution used at common substations are not applied so easily to mobile substations, due absence of infrastructure (media) or difficulty to insert the mobile substation data in existing automation network not long. The ideal media must supply covering in a great geographic area to satisfy presented requirements. The implantation costs of this big infrastructure are expensive, however a existing operator may be used. Two services that fulfill that requirements are satellite and cellular telephony. This work presents a solution for automation of mobile substations through satellite. It was successfully implanted at a brazilian electric energy concessionaire named COSERN. The operation became transparent to operators. Other gotten benefits had been operational security, quality in the supply of electric energy and costs reduction. The project presented is a new solution, designed to substations and general applications where few data should be transmitted, but there is difficulties in relation to the media. Despite the satellite having been used, the same resulted can be gotten using celullar telephony, through Short Messages or packet networks as GPRS or EDGE.

Validação de uma metodologia de ensaio de resistência ao cisalhamento para avaliação da aderência de interfaces revestimento metálico-bainha de cimento aplicada a poços de petróleo

Improving the adherence between oilwell metallic casing and cement sheath potentially decrease the number of corrective actions present/y necessary for Northeastern wells submitted to steam injection. In addition to the direct costs involved in the corrective operations, the economic impact of the failure of the primary cementing aIso includes the loss in the production of the well. The adherence between casing and cement is current/y evaluated by a simple shear tests non standardized by the American Petroleum Institute (API). Therefore, the objective of the present is to propose and evaluate a standardized method to assess the adherence of oilwell metallic casing to cement sheath. To that end, a section of a cemented oilwell was simulated and used to test the effect of different parameters on the shear stress of the system. Surface roughness and different cement compositions submitted or not to thermal cycling were evaluated. The results revealed that the test geometry and parameters proposed yielded different values for the shear stress of the system, corresponding to different adherent conditions between metallic casing and cement sheath

Avaliação da temperatura de cristalização da parafina em sistemas: parafina, solvente e tensoativo

The formation of paraffin deposits is common in the petroleum industry during production, transport and treatment stages. It happens due to modifications in the thermodynamic variables that alter the solubility of alkanes fractions present in petroleum. The deposition of paraffin can provoke significant and growing petroleum losses, arriving to block the flow, hindering to the production. This process is associated with the phases equilibrium L-S and the stages and nucleation, growth and agglomeration the crystals. That process is function of petroleum intrinsic characteristics and temperature and pressure variations, during production. Several preventive and corrective methods are used to control the paraffin crystallization, such as: use of chemical inhibitors, hot solvents injection, use of termochemistry reactions, and mechanical removal. But for offshore exploration this expensive problem needs more investigation. Many studies have been carried through Wax Appearance Temperature (WAT) of paraffin; therefore the formed crystals are responsible for the modification of the reologics properties of the oil, causing a lot off operational problems. From the determination of the WAT of a system it is possible to affirm if oil presents or not trend to the formation of organic deposits, making possible to foresee and to prevent problems of wax crystallization. The solvent n-paraffin has been widely used as fluid of perforation, raising the production costs when it is used in the removal paraffin deposits, needing an operational substitute. This study aims to determine the WAT of paraffin and the interference off additives in its reduction, being developed system paraffin/solvent/surfactant that propitiates the wax solubilization. Crystallization temperatures in varied paraffin concentrations and different solvents were established in the first stage of the experiments. In the second stage, using the methodology of variation of the photoelectric signal had been determined the temperature of crystallization of the systems and evaluated the interferences of additives to reduction of the WAT. The experimental results are expressed in function of the variations of the photoelectric signals during controlled cooling, innovating and validating this new methodology to determine WAT, relatively simple with relation the other applied that involve specific equipments and of high cost. Through the curves you differentiate of the results had been also identified to the critical stages of growth and agglomeration of the crystals that represent to the saturation of the system, indicating difficulties of flow due to the increase of the density