Análise dos Processos de Flotação e Oxidação Avançada para o Tratamento de Efluente Modelo da Indústria do Petróleo

The generation of wastes in most industrial process is inevitable. In the petroleum industry, one of the greatest problems for the environment is the huge amount of produced water generated in the oil fields. This wastewater is a complex mixture and present great amounts. These effluents can be hazardous to the environmental without adequate treatment. This research is focused in the analysis of the efficiencies of the flotation and photo-oxidation processes to remove and decompose the organic compounds present in the produced water. A series of surfactants derivated from the laurilic alcohol was utilized in the flotation to promote the separation. The experiments have been performed with a synthetic wastewater, carefully prepared with xylene. The experimental data obtained using flotation presented a first order kinetic, identified by the quality of the linear data fitting. The best conditions were found at 0.029 g.L-1 for the surfactant EO 7, 0.05 g.L-1 for EO 8, 0.07 g.L-1 for EO 9, 0.045 g.L-1 for EO 10 and 0.08 g.L-1 for EO 23 with the following estimated kinetic constants: 0.1765, 0.1325, 0.1210, 0.1531 and 0.1699 min-1, respectively. For the series studied, the most suitablesurfactant was the EO 7 due to the lower reagent consumption, higher separation rate constant and higher removal efficiency of xylene in the aqueous phase (98%). Similarly to the flotation, the photo-Fenton process shows to be efficient for degradation of xylene and promoting the mineralization of the organic charge around 90% and 100% in 90 min

Estudo teórico aplicado ao petróleo: estabilidade dos alcenos e recuperação terciária

The present work aims to study the theoretical level of some processes employed in the refining of petroleum fractions and tertiary recovery of this fluid. In the third chapter, we investigate a method of hydrogenation of oil fractions by QTAIM (Quantum Theory of Atoms in Molecules) and thermodynamic parameters. The study of hydrogenation reactions, and the stability of the products formed, is directly related to product improvement in the petrochemical refining. In the fourth chapter, we study the theoretical level of intermolecular interactions that occur in the process of tertiary oil recovery, or competitive interactions involving molecules of non-ionic surfactants, oil and quartz rock where oil is accumulated. Calculations were developed using the semiempirical PM3 method (Parametric Model 3). We studied a set of ten non-ionic surfactants, natural and synthetic origin. The study of rock-surfactant interactions was performed on the surface of the quartz (001) completely hydroxylated. Results were obtained energetic and geometric orientations of various surfactants on quartz. QTAIM was obtained through the analysis of the electron density of interactions, and thus, providing details about the formation of hydrogen bonds and hydrogen-hydrogen systems studied. The results show that the adsorption of ethoxylated surfactants in the rock surface occurs through the hydrogen bonding of the type CH---O, and surfactants derivatives of polyols occurs by OH---O bonds. For structures adsorption studied, the large distance of the surfactant to the surface together with the low values of charge density, indicate that there is a very low interaction, characterizing physical adsorption in all surfactants studied. We demonstrated that surfactants with polar group comprising oxyethylene units, showed the lowest adsorption onto the surface of quartz, unlike the derivatives of polyols

Estudo paramétrico da recuperação de petróleo pesado por aquecimento eletromagnético resistivo

Electrical resistive heating (ERH) is a thermal method used to improve oil recovery. It can increase oil rate and oil recovery due to temperature increase caused by electrical current passage through oil zone. ERH has some advantage compared with well-known thermal methods such as continuous steam flood, presenting low-water production. This method can be applied to reservoirs with different characteristics and initial reservoir conditions. Commercial software was used to test several cases using a semi-synthetic homogeneous reservoir with some characteristics as found in northeast Brazilian basins. It was realized a sensitivity analysis of some reservoir parameters, such as: oil zone, aquifer presence, gas cap presence and oil saturation on oil recovery and energy consumption. Then it was tested several cases studying the electrical variables considered more important in the process, such as: voltage, electrical configurations and electrodes positions. Energy optimization by electrodes voltage levels changes and electrical settings modify the intensity and the electrical current distribution in oil zone and, consequently, their influences in reservoir temperature reached at some regions. Results show which reservoir parameters were significant in order to improve oil recovery and energy requirement in for each reservoir. Most significant parameters on oil recovery and electrical energy delivered were oil thickness, presence of aquifer, presence of gas cap, voltage, electrical configuration and electrodes positions. Factors such as: connate water, water salinity and relative permeability to water at irreducible oil saturation had low influence on oil recovery but had some influence in energy requirements. It was possible to optimize energy consumption and oil recovery by electrical variables. Energy requirements can decrease by changing electrodes voltages during the process. This application can be extended to heavy oil reservoirs of high depth, such as offshore fields, where nowadays it is not applicable any conventional thermal process such as steam flooding

Influência da areia argilosa na recuperação de petróleo por injeção de vapor

Continuous steam injection is one of heavy oil thermal recovery methods used in the Brazilian Northeast because of high occurrence of heavy oil reservoir. In this process, the oil into the reservoir is heated while reduces, substantially, its viscosity and improves the production. This work analyzed how the shaly sand layers influenced in the recovery. The studied models were synthetics, but the used reservoir data can be extrapolated to real situations of Potiguar Basin. The modeling was executed using the STARS - Steam Thermal and Advanced Process Reservoir Simulator - whose version was 2007.10. STARS is a tool of CMG Computer Modeling Group. The study was conducted in two stages, the first we analyzed the influence of reservoir parameters in the thermal process, so some of these were studied, including: horizontal permeability of the reservoir and the layer of shaly sand, ratio of horizontal permeability to vertical permeability, the influence of capillary pressure layer of shaly sand and as the location and dimensions of this heterogeneity can affect the productivity of oil. Among the parameters studied the horizontal permeability of the reservoir showed the most significant influence on the process followed by diversity. In the second stage three models were selected and studied some operational parameters such as injection rate, distance between wells, production time and completion intervals. Among the operating parameters studied the low rate and intermediate distances between wells showed the best recoveries

Análise da recuperação em reservatório de gás com baixa permeabilidade (TIGHT GAS) através do fraturamento hidráulico

With the increasing of energetic consumption in the worldwile, conventional reservoirs, known by their easy exploration and exploitation, are not being enough to satisfy this demand, what has made necessary exploring unconventional reservoirs. This kind of exploration demands developing more advanced technologies to make possible to exploit those hydrocarbons. Tight gas is an example of this kind of unconventional reservoir. It refers to sandstone fields with low porosity, around 8%, and permeabilities between 0.1 and 0.0001 mD, which accumulates considerable amounts of natural gas. That natural gas can only be extracted by applying hydraulic fracturing, aiming at stimulating the reservoir, by creating a preferential way through the reservoir to the well, changing and making easier the flow of fluids, thus increasing the productivity of those reservoirs. Therefore, the objective of this thesis is analyzing the recovery factor of a reservoir by applying hydraulic fracturing. All the studies were performed through simulations using the IMEX software, by CMG (Computer Modelling Group), in it 2012.10 version

Análise do comportamento reológico de pastas de cimento contendo resíduos de pneu para poços de petróleo

The low tenacity presented by the Portland cement pastes used in the oil wells cementation has been motivating several researches with attention focused on alternative materials. Additives have been developed to generate flexible pastes with mechanical resistance capable to support the expansions and retractions of the metallic covering of the wells that submit to the steam injection, technique very used to increase the recovery factor in oil reservoirs with high viscosity. A fresh paste with inadequate rheological behavior may commit the cementation process seriously, involving flaws that affect the performance of the paste substantially in the hardened state. This work proposes the elaboration and the rheological analysis of Portland cement pastes with addition of residues of rubber tire in several proportions, with the aim of minimizing the damages provoked in the hem cementing of these wells. By thermogravimetric analysis, the particles of eraser that go by the sieve of 0,5mm (35 mesh) opening and treated superficially with NaOH solution of 1 mol/L presented appropriate thermal resistance for wells that submit to thermal cyclic. The evaluation of the study based on the results of the rheological analysis of the pastes, complemented by the mechanical analysis, thickening, stability, tenor of free water and filtrate loss, being used as parameter a paste reference, without rubber addition. The results showed satisfactory rheology, passive of few corrections; considerable loss of mechanical resistance (traction and compression), compensated by earnings of tenacity, however with established limits for its application in oil wells; satisfactory stability, free water and thickening time

Adição de vermiculita expandida mícron em pastas de baixa densidade para cimentação de poços de petróleo

The northeastern region of Brazil has a large number of wells producing oil using a method of secondary recovery steam injection, since the oil produced in this region is essentially viscous. This recovery method puts the cement / coating on thermal cycling, due to the difference in coefficient of thermal expansion between cement and metal coating causes the appearance of cracks at this interface, allowing the passage of the annular fluid, which is associated with serious risk socioeconomic and environmental. In view of these cracks, a correction operation is required, resulting in more costs and temporary halt of production of the well. Alternatively, the oil industry has developed technology for adding new materials in cement pastes, oil well, providing high ductility and low density in order to withstand the thermo-mechanical loads generated by the injection of water vapor. In this context, vermiculite, a clay mineral found in abundance in Brazil has been applied in its expanded form in the construction industry for the manufacture of lightweight concrete with excellent insulation and noise due to its high melting point and the presence of air in their layers lamellar. Therefore, the vermiculite is used for the purpose of providing low-density cement paste and withstand high temperatures caused by steam injection. Thus, the present study compared the default folder containing cement and water with the folders with 6%, 8% and 10% vermiculite micron conducting tests of free water, rheology and compressive strength where it obtained the concentration of 8 % with the best results. Subsequently, the selected concentration, was compared with the results recommended by the API standard tests of filtered and stability. And finally, analyzed the results from tests of specific gravity and time of thickening. Before the study we were able to make a folder with a low density that can be used in cementing oil well in order to withstand the thermo-mechanical loads generated by steam injection

Formulação de pastas cimentícias com adição de suspensões de quitosana para cimentação de poços de petróleo

Primary cementing is one of the main operations in well drilling responsible for the mechanical stability and zonal isolation during the production of oil. However, the cement sheath is constantly under mechanical stresses and temperature variations caused by the recovery of heavy oil. In order to minimize fracture and wear of the cement sheath, new admixtures are developed to improve the properties of Portland cement slurries and avoid environmental contamination caused by leaking gas and oil. Polymers with the ability to form polymeric films are candidates to improve the properties of hardened cement slurries, especially their fracture energy. The present study aimed at evaluating the effect of the addition of a chitosan suspension on cement slurries in order to improve the properties of the cement and increase its performance on heavy oil recovery. Chitosan was dissolved in acetic ac id (0.25 M and 2 M) and added to the formulation of the slurries in different concentrations. SEM analyses confirmed the formation of polymeric films in the cementitious matrix. Strength tests showed higher fracture energy compared to slurries without the addition of chitosan. The formation of the polymeric films also reduced the permeability of the slurry. Therefore, chitosan suspensions can be potentially used as cementing admixtures for heavy oil well applications

Adição de resíduo cerâmico em pastas geopoliméricas para cimentação de poços de petróleo

The development of activities the of oil and gas sector have promoted the search for suitable materials for cementing oil wells. In the state of the Rio Grande do Norte, the integrity of the cement sheath tends to be impaired during steam injection, a procedure necessary to increase oil recovery in reservoirs with low-viscosity oil. The geopolymer is a material that can be used as alternative cement, since it has been used in the production of fire-resistant components, building structures, and for the control of toxic or radioactive residues. Geopolymers result from condensation polymer alkali aluminosilicates and silicates resulting three-dimensional polymeric structures. They are produced in a manner different from that of Portland cement, which is made an activating solution that is mixed with geopolymer precursor. Among the few works studied allowed us to conclude that the pastes prepared with metakaolin as precursor showed better performance of its properties. Several studies show the addition of waste clay as a means of reducing cost and improving end of the folder properties. On this basis, the goal is to study the influence of the addition of ceramic waste in geopolymer paste. To develop the study of rheology tests were carried out, filtered, thickening time, compressive strength, free water, specific gravity and permeability, according to the American Pretoleum Institute (API). The results for all formulations studied show that the folders have high mechanical strength to a light paste; low filtrate volume, absence of free water, very low permeability, slurry, consistent with a light paste, and thickening time low that can be corrected with the use of a retardant handle. For morphological characterization, microstructural, physical, chemical and thermal tests were carried out by XRD, MEV, DTA, TG, FTIR. In the trial of XRD, it was found that geopolymer is an amorphous material, with a peak of crystalline kaolinite. In tests of TG / DTA, revealed the presence of a significant event, which represents the mass loss related to water, and also observed the reduction of weight loss by increasing the concentration of ceramic waste. In the trial of MEV, we found a uniform matrix without the presence of other phases. In the trial of FT-IR, we observed the presence of the band related to water. From all results it was determined that the optimum concentration range of use is between 2.5 and 5% of waste ceramic

Compósitos Portland-biopolímeros para cimentação de poços de petróleo

The oil production in mature areas can be improved by advanced recovery techniques. In special, steam injection reduces the viscosity of heavy oils, thus improving its flow to surrounding wells. On the other hand, the usually high temperatures and pressures involved in the process may lead to cement cracking, negatively affecting both the mechanical stability and zonal isolation provided by the cement sheath of the well. The addition of plastic materials to the cement is an alternative to prevent this scenario. Composite slurries consisting of Portland cement and a natural biopolymer were studied. Samples containing different contents of biopolymer dispersed in a Portland cement matrix were prepared and evaluated by mechanical and rheological tests in order to assess their behavior according to API (American Petroleum Institute) guidelines. FEM was also applied to map the stress distribution encountered by the cement at bottom bole. The slurries were prepared according to a factorial experiment plan by varying three parameters, i.e., cement age, contents of biopolymer and water-to-cement ratio. The results revealed that the addition of the biopolymer reduced the volume of free water and the setting time of the slurry. In addition, tensile strength, compressive strength and toughness improved by 30% comparing hardened composites to plain Portland slurries. FEM results suggested that the stresses developed at bottomhole may be 10 to 100 times higher than the strength of the cement as evaluated in the lab by unconfined mechanical testing. An alternative approach is proposed to adapt the testing methodology used to evaluate the mechanical behavior of oilwell cement slurries by simulating the confined conditions encountered at bottornhole

Aditivação de pastas geopoliméricas com tetraborato de sódio e látex não iônico para cimentação de Poços de Petróleo

The development of activities in the oil and gas sector has been promoting the search for materials more adequate to oilwell cementing operation. In the state of Rio Grande do Norte, the cement sheath integrity tend to fail during steam injection operation which is necessary to increase oil recovery in reservoir with heavy oil. Geopolymer is a material that can be used as alternative cement. It has been used in manufacturing of fireproof compounds, construction of structures and for controlling of toxic or radioactive waste. Latex is widely used in Portland cement slurries and its characteristic is the increase of compressive strength of cement slurries. Sodium Tetraborate is used in dental cement as a retarder. The addition of this additive aim to improve the geopolymeric slurries properties for oilwell cementing operation. The slurries studied are constituted of metakaolinite, potassium silicate, potassium hydroxide, non-ionic latex and sodium tetraborate. The properties evaluated were: viscosity, compressive strength, thickening time, density, fluid loss control, at ambient temperature (27 ºC) and at cement specification temperature. The tests were carried out in accordance to the practical recommendations of the norm API RP 10B. The slurries with sodium tetraborate did not change either their rheological properties or their mechanical properties or their density in relation the slurry with no additive. The increase of the concentration of sodium tetraborate increased the water loss at both temperatures studied. The best result obtained with the addition of sodium tetraborate was thickening time, which was tripled. The addition of latex in the slurries studied diminished their rheological properties and their density, however, at ambient temperature, it increased their compressive strength and it functioned as an accelerator. The increase of latex concentration increased the presence of water and then diminished the density of the slurries and increased the water loss. From the results obtained, it was concluded that sodium tetraborate and non-ionic latex are promising additives for geopolymer slurries to be used in oilwell cementing operation

Estudo paramétrico da recuperação de óleo no processo de drenagem gravitacional com injeção de CO2

The gas injection has become the most important IOR process in the United States. Furthermore, the year 2006 marks the first time the gas injection IOR production has surpassed that of steam injection. In Brazil, the installation of a petrochemical complex in the Northeast of Brazil (Bahia State) offers opportunities for the injection of gases in the fields located in the Recôncavo Basin. Field-scale gas injection applications have almost always been associated with design and operational difficulties. The mobility ratio, which controls the volumetric sweep, between the injected gas and displaced oil bank in gas processes, is typically unfavorable due to the relatively low viscosity of the injected gas. Furthermore, the difference between their densities results in severe gravity segregation of fluids in the reservoirs, consequently leading to poor control in the volumetric sweep. Nowadays, from the above applications of gas injection, the WAG process is most popular. However, in attempting to solve the mobility problems, the WAG process gives rise to other problems associated with increased water saturation in the reservoir including diminished gas injectivity and increased competition to the flow of oil. The low field performance of WAG floods with oil recoveries in the range of 5-10% is a clear indication of these problems. In order to find na effective alternative to WAG, the Gas Assisted Gravity Drainage (GAGD) was developed. This process is designed to take advantage of gravity force to allow vertical segregation between the injected CO2 and reservoir crude oil due to their density difference. This process consists of placing horizontal producers near the bottom of the pay zone and injecting gás through existing vertical wells in field. Homogeneous models were used in this work which can be extrapolated to commercial application for fields located in the Northeast of Brazil. The simulations were performed in a CMG simulator, the STARS 2007.11, where some parameters and their interactions were analyzed. The results have shown that the CO2 injection in GAGD process increased significantly the rate and the final recovery of oil

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

Simulador de dano à formação, aplicado ao Projeto e à execução da perfuração de poços de petróleo

With the high oil price variability, the petroleum and the reservoir engineers are usually face to face on how they can evaluate the well performance and productivity. They can improve high productivity from the well construction to the secondary recoveries, but they have never tried a measurement in the drilling operations about the lower productivity index. As a rule, frequently the drilling operations hear from the reservoir engineering and geology that, if there is a formation damage, probably some drilling operations practices were not done properly or the good practice in petroleum engineering or mud engineering were not observed. The study in this working search is an attempt of how to measure a formation damage just from the project drilling to the drilling operations, with datum from the fields in Brazilian northeast and putting into practice a Simulator developed from the modeling on the theory offered by different experts and sources in formation damage

Incorporação de resíduo cerâmico para prevenção da retrogressão da resistência de cimentos de poços de petróleo submetidos à injeção de vapor

Steam injection is the most used thermal recovery method of oil nowadays because of the high degree of development of the technique that allows high recovery factors. However, injection of superheated steam into the reservoir affects the entire structure of the well, including the cemented layer that presents a retrogression of compressive strength and increases the permeability due to formation of more crystalline and denser phases at temperatures above 110 °C. These changes result in failures in the cement that favor the entrance of formation fluids into the annulus space resulting in unsafe operations and restrictions in the economic life of the well. But the strength retrogression can be prevented by partial replacement of cement by silica-based materials that reduce the CaO/SiO2 ratio of cement slurries changing the trajectory of the reactions, converting those deleterious phases in phases with satisfactory mechanical strength and permeability. The aim of this study was to evaluate the behavior of a ceramic waste material rich in silica in partial and total substitution of a mineral additive used to fight the strength retrogression of cement slurries subjected to high temperatures. The evaluation was made by compression, X-ray diffraction (XRD) and thermogravimetry (TG/DTG). The samples were submitted to a cycle of low temperature (38 °C) for 28 days and a cycle of low temperature followed by exposure to 280 ºC and 1000 psi by 3 days. The results showed that slurries with additions of up to 30% of the waste material are not enough to prevent the strength retrogression, while slurries with additions of the waste material combined with silica flour in various proportions produced hydrated products of low Ca/Si ratios that maintained the compressive strength at satisfactory levels