Given the complexity involved when modeling heterogeneous and anisotropic formations, this condition is usually ignored, supposing that the well is surrounded by a homogenous and isotropic medium. The main objective of this paper is to present a method that shows the error that might occur when the condition of homogeneity and isotropy is not satisfied, when determining collapse pressure in a formation containing planes of weakness. Although the literature presents some studies, there is not a clear method for determining the collapse pressure of a well that takes into account the mechanical properties of the planes of weakness contained in the formation. The proposed method is based on the Mohr Coulomb criterion for homogeneous and isotropic formations and the criterion of Jaeger and Cook (1979) for laminated anisotropic media. It constitutes a robust tool that calculates the collapse pressure in highly complex configurations, contributing thus to prevent waste of time and money by more accurately considering the actual behavior of laminated formations. The method includes: the deduction of the direction cosine equation, the proposal of an objective function, the construction of a collapse pressure profile, and the sensitivity analysis of the collapse pressure with colored rosettes. A real case was selected to implement the proposed method.
{"title":"Method to determine the weakness planes effect on the calculation of the collapse pressure of oil wells","authors":"Juan-David Velilla-Uribe, Jorge-Luis Cáceres-Montero, Publio-Alejandro Sandoval, Reinel Corzo-Rueda, Zuly Calderón-Carrillo","doi":"10.29047/01225383.244","DOIUrl":"https://doi.org/10.29047/01225383.244","url":null,"abstract":"Given the complexity involved when modeling heterogeneous and anisotropic formations, this condition is usually ignored, supposing that the well is surrounded by a homogenous and isotropic medium. The main objective of this paper is to present a method that shows the error that might occur when the condition of homogeneity and isotropy is not satisfied, when determining collapse pressure in a formation containing planes of weakness. \u0000Although the literature presents some studies, there is not a clear method for determining the collapse pressure of a well that takes into account the mechanical properties of the planes of weakness contained in the formation. The proposed method is based on the Mohr Coulomb criterion for homogeneous and isotropic formations and the criterion of Jaeger and Cook (1979) for laminated anisotropic media. It constitutes a robust tool that calculates the collapse pressure in highly complex configurations, contributing thus to prevent waste of time and money by more accurately considering the actual behavior of laminated formations. The method includes: the deduction of the direction cosine equation, the proposal of an objective function, the construction of a collapse pressure profile, and the sensitivity analysis of the collapse pressure with colored rosettes. A real case was selected to implement the proposed method.","PeriodicalId":55200,"journal":{"name":"Ct&f-Ciencia Tecnologia Y Futuro","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2010-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88713591","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The aim of this work is to contribute to the current understanding on the role of the support’s acidic properties in the hydrogenating function of NiMo/-Al2O3 type catalysts during hydrodearomatization (HDA) and dibenzothiophene (DBT) type molecules desulfurization. NiMo/-Al2O3-B2O3 catalysts of different B2O3 (0, 2, 3, 6 and 8 wt.%) contents were prepared and tested in independent and simultaneous naphthalene (NP) HDA and DBT hydrodesulfurization (HDS) reactions. For HDA the catalytic activity as a function of the B2O3 content followed a volcano-shape trend, with a maximum around 3 wt.% of B2O3. In DBT desulfurization boron was found to have a positive effect in the development of the HYD route of desulfurization possibly due to an increase in total acidity. Conversely, the direct desulfurization route (DDS) was negatively affected by boron addition. The presence of NP during the HDS of DBT was found to have a significant effect in neither total HDS activity nor the HYD/DDS selectivity. The findings in this paper are significant for ultra-deep HDS of heavy oil cuts where increasing in the selectivity to HYD is a must because highly refractory alkyl-DBTs mostly react by this reaction route.
{"title":"Evaluating the functionalities of NiMo/y-Al2O3-B2O3 catalysts in naphthalene hydrodearomatization and dibenzothiophene hydrodesulfurization","authors":"V. Baldovino-Medrano, A. Centeno, S. Giraldo","doi":"10.29047/01225383.290","DOIUrl":"https://doi.org/10.29047/01225383.290","url":null,"abstract":"The aim of this work is to contribute to the current understanding on the role of the support’s acidic properties in the hydrogenating function of NiMo/-Al2O3 type catalysts during hydrodearomatization (HDA) and dibenzothiophene (DBT) type molecules desulfurization. NiMo/-Al2O3-B2O3 catalysts of different B2O3 (0, 2, 3, 6 and 8 wt.%) contents were prepared and tested in independent and simultaneous naphthalene (NP) HDA and DBT hydrodesulfurization (HDS) reactions. For HDA the catalytic activity as a function of the B2O3 content followed a volcano-shape trend, with a maximum around 3 wt.% of B2O3. In DBT desulfurization boron was found to have a positive effect in the development of the HYD route of desulfurization possibly due to an increase in total acidity. Conversely, the direct desulfurization route (DDS) was negatively affected by boron addition. The presence of NP during the HDS of DBT was found to have a significant effect in neither total HDS activity nor the HYD/DDS selectivity. The findings in this paper are significant for ultra-deep HDS of heavy oil cuts where increasing in the selectivity to HYD is a must because highly refractory alkyl-DBTs mostly react by this reaction route.","PeriodicalId":55200,"journal":{"name":"Ct&f-Ciencia Tecnologia Y Futuro","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2010-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89427307","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A method that allows the creation of the Synthetic Sonic Log (SSL) was developed from the Spontaneous Potential (SP) logs, the resistivity logs of the flushed zone (SN), and the resistivity zone of the uninvaded zone (ILD), using Artificial Neural Networks (ANN). The SSL was obtained with the created tool calledGeneration of Synthetic Sonic Logs (GSSL). The results obtained are presented hereinafter: in the Colorado 70 well, 90% of the generated SSL data present errors of less than 10%; in the Colorado 72 well; 53% of the SSL data obtained with the tool are below 5% error, in the Colorado 75 well, 80% of the SSL data present errors of less than 10%, and finally, the SSL generated for the Colorado 38 well follows the behavior of the original Sonic Logs of the well in an accurate manner. From the foregoing we conclude that the quality of the created tool is good and that the deviations are minimal in the times of transit of synthetic sonic profile.
{"title":"Methodology to design of synthetic sonic log (SSL), using artificial neural networks. Colorado field application","authors":"Carlos-Andrés Ayala Marín, Christiann-Camilo García-Yela","doi":"10.29047/01225383.242","DOIUrl":"https://doi.org/10.29047/01225383.242","url":null,"abstract":"A method that allows the creation of the Synthetic Sonic Log (SSL) was developed from the Spontaneous Potential (SP) logs, the resistivity logs of the flushed zone (SN), and the resistivity zone of the uninvaded zone (ILD), using Artificial Neural Networks (ANN). The SSL was obtained with the created tool calledGeneration of Synthetic Sonic Logs (GSSL). \u0000The results obtained are presented hereinafter: in the Colorado 70 well, 90% of the generated SSL data present errors of less than 10%; in the Colorado 72 well; 53% of the SSL data obtained with the tool are below 5% error, in the Colorado 75 well, 80% of the SSL data present errors of less than 10%, and finally, the SSL generated for the Colorado 38 well follows the behavior of the original Sonic Logs of the well in an accurate manner. From the foregoing we conclude that the quality of the created tool is good and that the deviations are minimal in the times of transit of synthetic sonic profile.","PeriodicalId":55200,"journal":{"name":"Ct&f-Ciencia Tecnologia Y Futuro","volume":"2007 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2010-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86592038","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Sandro Faruc González, J. A. Carrillo, M. Núñez, L. Hoyos, S. Giraldo
The world petroleum industry shows a decreasing in the oil reserves, specially the light kind. For this reason is very important to implement process schemes that give the possibility to improve the recuperation of valuable products of heavy oil. In this case the bottom processing in each one of the petroleum refining stages earns great importance with the purpose of maximizing the quantity of fuel by barrel of raw processed. Therefore, it has been proposed the modification of the currently vacuum residues process scheme in the Ecopetrol`s Barrancabermeja refinery (DEMEX-Visbreaking-Hydroprocessing). That modification consists in the incorporation of an additional Visbreaking stage, previous at DEMEX extraction stage. This investigation was developed with plant pilot tests combined with statistical models that predict the yield and the quality of the products obtained in the industrial plants. These models were developed by the Instituto Colombiano de Petróleo (ICP). The modified scheme Visbreaking I-DEMEX- Visbreaking II- Hydroprocessing, gives the possibility to increase the yield of middle distillates. Besides decrease the quantity of demetalized oil produced in DEMEX stage. This reduction is very favorable since environmental point of view, because it allows have a percentage of free capacity in the Hydroprocessing unit in order to removed sulfur of valuable products like Diesel and in this way to respect the environment law to this kind of fuel.
{"title":"Modified design for vacuum residue processing","authors":"Sandro Faruc González, J. A. Carrillo, M. Núñez, L. Hoyos, S. Giraldo","doi":"10.29047/01225383.245","DOIUrl":"https://doi.org/10.29047/01225383.245","url":null,"abstract":"The world petroleum industry shows a decreasing in the oil reserves, specially the light kind. For this reason is very important to implement process schemes that give the possibility to improve the recuperation of valuable products of heavy oil. In this case the bottom processing in each one of the petroleum refining stages earns great importance with the purpose of maximizing the quantity of fuel by barrel of raw processed. Therefore, it has been proposed the modification of the currently vacuum residues process scheme in the Ecopetrol`s Barrancabermeja refinery (DEMEX-Visbreaking-Hydroprocessing). That modification consists in the incorporation of an additional Visbreaking stage, previous at DEMEX extraction stage. \u0000This investigation was developed with plant pilot tests combined with statistical models that predict the yield and the quality of the products obtained in the industrial plants. These models were developed by the Instituto Colombiano de Petróleo (ICP). \u0000The modified scheme Visbreaking I-DEMEX- Visbreaking II- Hydroprocessing, gives the possibility to increase the yield of middle distillates. Besides decrease the quantity of demetalized oil produced in DEMEX stage. This reduction is very favorable since environmental point of view, because it allows have a percentage of free capacity in the Hydroprocessing unit in order to removed sulfur of valuable products like Diesel and in this way to respect the environment law to this kind of fuel.","PeriodicalId":55200,"journal":{"name":"Ct&f-Ciencia Tecnologia Y Futuro","volume":"29 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2010-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77840139","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
F. Escobar, J. Martínez, Matilde Montealegre-Madero
In many activities of the oil industry, engineers have to deal with completion and stimulation treatment fluids such as polymer solutions and some heavy crude oils which obey a non-Newtonian power-law behavior. When it is required to conduct a treatment with a non-Newtonian fluid in an oil-bearing formation, thiscomes in contact with conventional oil which possesses a Newtonian nature. This implies the definition of two media with entirely different mobilities. If a pressure test is run in such a system, the interpretation of data from such a test through the use of conventional straight-line method may be erroneous and may not provide a way for verification of the results obtained. In this work, the signature of the pressure derivative curve is investigated to understand and ease the interpretation of the well test data in reservoirs with non-Newtonian power-law fluids. Specifically, the Tiab’s Direct Synthesis (TDS) technique is implemented using some characteristics features found on the pressure and pressure derivative curves. Hence, new equations are introduced to estimate permeability, non-Newtonian bank radius and skin factor. Permeability can be verified. The proposed methodology was successfully verified by its application to an example reported in the literature and a synthetic case.
{"title":"Pressure and pressure derivative analysis for a well in a radial composite reservoir with a non-newtonian/newtonian interface","authors":"F. Escobar, J. Martínez, Matilde Montealegre-Madero","doi":"10.29047/01225383.243","DOIUrl":"https://doi.org/10.29047/01225383.243","url":null,"abstract":"In many activities of the oil industry, engineers have to deal with completion and stimulation treatment fluids such as polymer solutions and some heavy crude oils which obey a non-Newtonian power-law behavior. When it is required to conduct a treatment with a non-Newtonian fluid in an oil-bearing formation, thiscomes in contact with conventional oil which possesses a Newtonian nature. This implies the definition of two media with entirely different mobilities. If a pressure test is run in such a system, the interpretation of data from such a test through the use of conventional straight-line method may be erroneous and may not provide a way for verification of the results obtained. \u0000In this work, the signature of the pressure derivative curve is investigated to understand and ease the interpretation of the well test data in reservoirs with non-Newtonian power-law fluids. Specifically, the Tiab’s Direct Synthesis (TDS) technique is implemented using some characteristics features found on the pressure and pressure derivative curves. Hence, new equations are introduced to estimate permeability, non-Newtonian bank radius and skin factor. Permeability can be verified. The proposed methodology was successfully verified by its application to an example reported in the literature and a synthetic case.","PeriodicalId":55200,"journal":{"name":"Ct&f-Ciencia Tecnologia Y Futuro","volume":"26 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2010-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90280207","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In this paper a comparison is made between the performance of models developed by applying chemometric analysis to NIR and UVVIS spectral data obtained from feedsctock samples corresponding to the different Ecopetrol S.A., Barrancabermeja Refinery FCC units for predicting some important physicochemical properties. The results show the utility of both methodologies here evaluated to follow up the quality of these types of refinery streams and present the advantages and disadvantages of each methodology for predicting the feedstock properties here evaluated.
本文比较了采用化学计量学分析方法建立的模型的性能,这些模型采用近红外和紫外可见光谱数据,从不同的Ecopetrol sa, Barrancabermeja炼油厂催化裂化装置对应的原料样品中获得,用于预测一些重要的物理化学性质。结果显示了本文所评估的两种方法在跟踪这些类型的炼油厂流的质量方面的效用,并展示了每种方法在预测所评估的原料特性方面的优缺点。
{"title":"COMPARISON BETWEEN NIR AND UVVIS SPECTRA CHEMOMETRICS FOR PREDICTING FCC FEEDSTOCKS PROPERTIES","authors":"C. Baldrich, L. Novoa, A. Bueno","doi":"10.29047/01225383.444","DOIUrl":"https://doi.org/10.29047/01225383.444","url":null,"abstract":"In this paper a comparison is made between the performance of models developed by applying chemometric analysis to NIR and UVVIS spectral data obtained from feedsctock samples corresponding to the different Ecopetrol S.A., Barrancabermeja Refinery FCC units for predicting some important physicochemical properties. The results show the utility of both methodologies here evaluated to follow up the quality of these types of refinery streams and present the advantages and disadvantages of each methodology for predicting the feedstock properties here evaluated.","PeriodicalId":55200,"journal":{"name":"Ct&f-Ciencia Tecnologia Y Futuro","volume":"164 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2010-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73278095","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Maria Elizabeth Gómez, Liliana Santos, Néstor Tapias, Clemencia Vargas, J. Lizcano
Polycyclic Aromatics (PCA) are aromatic hydrocarbons and related sulphur and nitrogen compounds, containing three or more fused aromatic rings, which are considered as toxic compounds. PCA control is a complex task because the Base Oil production involves different processes with many variables such as pressure, temperature, feedstock quality, catalyst, etc. This study focuses on controlling the hydrotreating temperature as main variable in the reduction of PCA in Naphthenic Bases. Two Naphthenic distillate fractions taken from an industrial plant were hydrotreated in pilot plant at different temperatures. The results show that PCA are reduced as hydrotreating temperature increases; however there is an optimum temperature above it, the thermodynamic equilibrium of aromatic hydrogenation reverses, increasing as a result, the PCA content. These results were implemented in the industrial Unit by installing a hydrogen quench between the two industrial reactors to guarantee that the profile of temperature, due to exothermic character of some reactions, be always in the optimun operating range.
{"title":"PCA REDUCTION IN NAPHTHENIC BASE OILS BY OPTIMIZING HDT CONDITIONS","authors":"Maria Elizabeth Gómez, Liliana Santos, Néstor Tapias, Clemencia Vargas, J. Lizcano","doi":"10.29047/01225383.443","DOIUrl":"https://doi.org/10.29047/01225383.443","url":null,"abstract":"Polycyclic Aromatics (PCA) are aromatic hydrocarbons and related sulphur and nitrogen compounds, containing three or more fused aromatic rings, which are considered as toxic compounds. PCA control is a complex task because the Base Oil production involves different processes with many variables such as pressure, temperature, feedstock quality, catalyst, etc. This study focuses on controlling the hydrotreating temperature as main variable in the reduction of PCA in Naphthenic Bases. Two Naphthenic distillate fractions taken from an industrial plant were hydrotreated in pilot plant at different temperatures. The results show that PCA are reduced as hydrotreating temperature increases; however there is an optimum temperature above it, the thermodynamic equilibrium of aromatic hydrogenation reverses, increasing as a result, the PCA content. These results were implemented in the industrial Unit by installing a hydrogen quench between the two industrial reactors to guarantee that the profile of temperature, due to exothermic character of some reactions, be always in the optimun operating range. ","PeriodicalId":55200,"journal":{"name":"Ct&f-Ciencia Tecnologia Y Futuro","volume":"21 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2010-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83184936","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
F. Escobar, M. Montealegre, Daniel Carrillo-Moreno
Due to geologic and tectonic events many reservoirs have an elongated geometry in which dual-linear and single-linear flow regimes may be developed. The single-linear flow may be altered by changes in facies (mobility) or reservoir width (composite reservoir). Therefore, it is desirable to identify and characterize these types of systems which lead to competent decisions and adequate reservoir management. The identification and determination of parameters for such reservoirs are conducted by conventional techniques (straight-line method), type-curve matching of pressure versus time and the Tiab’s Direct Synthesis (TDS) technique. This last one has been lately presented for homogeneous and constant width reservoirs. In this paper, an extension of the TDS technique to incorporate variations in either mobility or reservoir width is presented. Several simulation experiments were run to understand the behavior of the reservoir under these new conditions. If the change of the mentioned parameters takes place after the dual- linear flow has ended a new half-slope line is observed on the pressure derivative curve. This new line is shifted upwards the original dual-linear line without regarding the variation of one of the studied parameter. When, the anomaly occurs during dual- linear flow the new half-slope line of the pressure derivative curve may be shifted upwards or downwards depending upon the magnitude of either mobility or reservoir width. This new line may not be referred as linear flow regime because it is really not. We have named it as pseudo-linear flow regime, instead. Therefore, a modification of the intercept of the ½-slope line from 0,5 for dual-linear flow regime to a greater or smaller value, which may be different from (single-linear flow case) has to be considered in order to provide new equations for the estimation of new values of either permeability or reservoir width. The proposed methodology was successfully verified by interpreting both synthetic and field pressure tests for elongated oil reservoirs which involve changes in either mobility or reservoir width during the path of the transient wave.
{"title":"PRESSURE AND PRESSURE DERIVATIVE TRANSIENT ANALYSIS WITHOUT TYPE-CURVE MATCHING FOR ELONGATED RESERVOIRS WITH CHANGES IN FACIES OR WIDTH","authors":"F. Escobar, M. Montealegre, Daniel Carrillo-Moreno","doi":"10.29047/01225383.441","DOIUrl":"https://doi.org/10.29047/01225383.441","url":null,"abstract":"Due to geologic and tectonic events many reservoirs have an elongated geometry in which dual-linear and single-linear flow regimes may be developed. The single-linear flow may be altered by changes in facies (mobility) or reservoir width (composite reservoir). Therefore, it is desirable to identify and characterize these types of systems which lead to competent decisions and adequate reservoir management. The identification and determination of parameters for such reservoirs are conducted by conventional techniques (straight-line method), type-curve matching of pressure versus time and the Tiab’s Direct Synthesis (TDS) technique. This last one has been lately presented for homogeneous and constant width reservoirs. In this paper, an extension of the TDS technique to incorporate variations in either mobility or reservoir width is presented. Several simulation experiments were run to understand the behavior of the reservoir under these new conditions. If the change of the mentioned parameters takes place after the dual- linear flow has ended a new half-slope line is observed on the pressure derivative curve. This new line is shifted upwards the original dual-linear line without regarding the variation of one of the studied parameter. When, the anomaly occurs during dual- linear flow the new half-slope line of the pressure derivative curve may be shifted upwards or downwards depending upon the magnitude of either mobility or reservoir width. This new line may not be referred as linear flow regime because it is really not. We have named it as pseudo-linear flow regime, instead. Therefore, a modification of the intercept of the ½-slope line from 0,5 for dual-linear flow regime to a greater or smaller value, which may be different from (single-linear flow case) has to be considered in order to provide new equations for the estimation of new values of either permeability or reservoir width. The proposed methodology was successfully verified by interpreting both synthetic and field pressure tests for elongated oil reservoirs which involve changes in either mobility or reservoir width during the path of the transient wave. ","PeriodicalId":55200,"journal":{"name":"Ct&f-Ciencia Tecnologia Y Futuro","volume":"43 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2010-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75911726","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In this work, the conventional cartesian straight-line pseudosteady-state solution and the Total Dissolved Solids (TDS) solution to estimate reservoir drainage area is applied to constant-pressure reservoirs to observe its accuracy. It was found that it performs very poorly in such systems, especially in those having rectangular shape. On the other hand, the pseudosteady-state solution of the TDS technique performs better in constant-pressure systems and may be applied only to regular square- or circular-shaped reservoirs with a resulting small deviation error. Therefore, new solutions for steady-state systems in circular, square and rectangular reservoir geometries having one or two constant-pressure boundaries are developed, compared and successfully verified with synthetic and real field cases. Automatic matching performed by commercial software sometimes are so time consuming and tedious which leads to another reason to use the proposed equations.
{"title":"Determination of reservoir drainage area for constant pressure systems using well test data","authors":"F. Escobar, Y. Hernández, D. Tiab","doi":"10.29047/01225383.440","DOIUrl":"https://doi.org/10.29047/01225383.440","url":null,"abstract":"In this work, the conventional cartesian straight-line pseudosteady-state solution and the Total Dissolved Solids (TDS) solution to estimate reservoir drainage area is applied to constant-pressure reservoirs to observe its accuracy. It was found that it performs very poorly in such systems, especially in those having rectangular shape. On the other hand, the pseudosteady-state solution of the TDS technique performs better in constant-pressure systems and may be applied only to regular square- or circular-shaped reservoirs with a resulting small deviation error. Therefore, new solutions for steady-state systems in circular, square and rectangular reservoir geometries having one or two constant-pressure boundaries are developed, compared and successfully verified with synthetic and real field cases. Automatic matching performed by commercial software sometimes are so time consuming and tedious which leads to another reason to use the proposed equations.","PeriodicalId":55200,"journal":{"name":"Ct&f-Ciencia Tecnologia Y Futuro","volume":"27 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2010-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85879407","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
William-Armando Fernández-Vera, R. Corzo, N. Saavedra
Wellbore instability in shales is attributed to many factors. Two of them are mechanical effects and physico-chemical effects. Drilling and drilling fluid cause physico-chemical interaction and the flux of water and ions that may alter the shale stress state through pore pressure and shale strength. This paper presents the analysis of the chemical osmosis phenomenon between drilling fluids and shale formations to evaluate the chemical parameters necessary for modeling the aqueous flux. These parameters are the drilling fluid activity (Adf), shale activity (Ash) and membrane efficiency (ME). This work also characterizes the shales for drilling purposes and describes an integrated methodology to obtain the magnitude of the chemical parameters. Furthermore, it is stated how the generation of effective osmotic pressure between the formation and drilling fluid define the water flux direction. Finally, the application of the results of the chemical analysis to Carbonera shale is presented. The design of laboratory tests for two mud formulations, Mud A and Mud B, and the field application is also showed. The Mud A is a balanced activity mud and the Mud B is a high salt concentration mud which may produce water flux out of the shale formation (dehydration) during drilling, in some sections of the wellbore, increasing the formation strength. The results presented in this paper will help to reduce the risks associated with wellbore instability during the drilling of shale formations and thereby lowering the overall non-productive time and reducing drilling costs.
{"title":"Selection of OBM salinity through effective osmotic pressure evaluation in carbonera shale for colombian foothills","authors":"William-Armando Fernández-Vera, R. Corzo, N. Saavedra","doi":"10.29047/01225383.436","DOIUrl":"https://doi.org/10.29047/01225383.436","url":null,"abstract":"Wellbore instability in shales is attributed to many factors. Two of them are mechanical effects and physico-chemical effects. Drilling and drilling fluid cause physico-chemical interaction and the flux of water and ions that may alter the shale stress state through pore pressure and shale strength. This paper presents the analysis of the chemical osmosis phenomenon between drilling fluids and shale formations to evaluate the chemical parameters necessary for modeling the aqueous flux. These parameters are the drilling fluid activity (Adf), shale activity (Ash) and membrane efficiency (ME). This work also characterizes the shales for drilling purposes and describes an integrated methodology to obtain the magnitude of the chemical parameters. Furthermore, it is stated how the generation of effective osmotic pressure between the formation and drilling fluid define the water flux direction. Finally, the application of the results of the chemical analysis to Carbonera shale is presented. The design of laboratory tests for two mud formulations, Mud A and Mud B, and the field application is also showed. The Mud A is a balanced activity mud and the Mud B is a high salt concentration mud which may produce water flux out of the shale formation (dehydration) during drilling, in some sections of the wellbore, increasing the formation strength. The results presented in this paper will help to reduce the risks associated with wellbore instability during the drilling of shale formations and thereby lowering the overall non-productive time and reducing drilling costs.","PeriodicalId":55200,"journal":{"name":"Ct&f-Ciencia Tecnologia Y Futuro","volume":"89 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2010-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80220007","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}