bluuebunny/crossref_metadata_2025_split huggingface dataset:
Durability of Portland Cement with and without Metal Oxide Weighting Material in a CO2/ H2S Environment
Authors: Fakhreldin Y.. 
Published: February 2012

Abstract
Hematite and hausmannite Ore ground are the most common material for weighting cement, it most adequately fulfills all the requirements and achieves the highest effective specific gravity, they usually dry blend with oil well cement to prepare high-density cement slurries. Cement sheath made of Portland cement and high-density additive of metal oxide such as Hematite and or hausmannite Ore ground decomposes much faster than cement sheath made of net or low Portland cement when it exposes to hydrogen sulfide (H2S) and or wet carbon dioxide (CO2) during the Well-Life. Hematite and hausmannite Ore ground's pre-densified cement sheath breaks down into many compounds through series of chemical reactions often involve an energy source that breaks apart the bonds of compounds. It decomposes into metal sulfide and or carbonate and calcium carbonate with a small concentration of iron sulfide as a result of the metal oxide and or Portland cement content sulfidation and carbonation reactions. Cement sheaths made of net, high, or low-Portland cement without high-density additive of metal oxide decomposition rate is less than cement sheath made of Portland cement with a high-density additive of metal oxide when it exposes to H2S and or CO2. H2S alone does not drastically decompose cement sheaths made of net, high, or low-Portland cement without high-density additive of metal oxide. H2S has limited impact on these cement sheath type as it reacts with iron(III) hydroxide [Fe(OH)3] in which is a part of 10% of the cement hydration products. Carbonic acid reacts with 90 % of the cement hydration products (calcium silicate hydrate and lime) and degrades cement sheath thoroughly. Despite that net cement-sheath does not drastically decompose when it exposed to H2S alone, it does when expose to CO2 alone and the decomposition rate increase in the as H2S concentration increase; unfortunately, it is not a case of if, it is a case of when cement sheaths with or without a high-density additive of metal oxide decompose due to the Carbonation and or Sulfidation reaction under wet CO2 and or sour environments. The cement sheath deterioration not only prevents well production or injection rate by reducing the inner diameter of the tubing and restrict access to the well with surveillance equipment for data acquisition but also damage the well-integrity and allow hydrocarbons along with H2S and CO2 to break through to the surface eventually. Immiscible gas injection is the worst case scenario ever, Portland cement sheath whether it contain a heavyweight additive of metal oxide or not, low-Portland or high Portland cannot sustain the acid gas, and it will lose its integrity. These wells have to fail in a short period due to the cement sheath deterioration. This paper discusses the durability of different oil well cement formulations under H2S / wet CO2 environments and demonstrates why some metal oxide containing cement more stable than others under sour CO2 reservoir downhole conditions.
Drilling Fluid: State of The Art and Future Trend
Authors: Apaleke Adeleye Sanmi , Al-Majed Abdulaziz , Hossain M. Enamul 
Published: February 2012

Abstract
In its endeavor to provide a sustainable flow of hydrocarbon energy, the Petroleum industry has been recognized by the general public as an industry that has negatively impacted the environment as a result of using either harmful materials or risky practices. This leads the industry to continuously invest in R&D to develop environmentally friendly technologies and products. For any new technology or product, the current R&D trend is toward the development of sustainable practices and expertise. Drilling fluids are necessary for drilling oil and gas wells. Unfortunately drilling fluids have become increasingly more complex in order to satisfy the various operational demands and challenges. The materials used in the process to improve the quality and functions of the drilling fluids, contaminates the subsurface and underground systems, landfills, and surrounding environment.
Due to the increasing environmental awareness and pressure from environmental agencies throughout the world, it is very important to look back to the drilling fluid technology to reassess its progress while it tries to make forward steps to improve the petroleum industry's position as an environment friendly industry. This article outlines the state-of-the-art of drilling fluids. The major types of drilling fluids, their strengths, limitations, and remedies to limitations are discussed. It also presents the current trend and the future challenges of this technology. In addition, future research guidelines are presented focusing on the development of environmentally friendly drilling fluids with zero impact on the environment. The paper concludes that future trend leads toward the development of sustainable drilling fluids.
A Model to Minimize Risk of Cement Plug failure in HPHT Conditions
Authors: Olutimehin Adekunle A , Odunuga Marilyn 
Published: February 2012

Abstract
Cement plugs play a central role in providing hydraulic isolation for oil and gas well integrity. They are routinely required for abandonment purposes, drilling sidetracks and wellbore remedial operations. Despite extensive industry experience from around the world, there are many cases in high-pressure, high-temperature (HPHT) wells where an otherwise straightforward cement plug operation has led to major non-productive time (NPT) resulting in escalation of overall well costs. There are a number of issues that increase risks especially when it involves placement of high-density cement slurries in HPHT wells. Downhole conditions present additional challenges, which make it difficult to do the job right the first time. Whenever a job goes wrong in these conditions there is often an impact apart from the immediate non-productive rig time. In addition to the increase in costs there are other associated impact, e.g. potential loss of downhole barrier with negative implications for safety and the environment.
Many studies and publications have highlighted the risk of unmitigated fluids contamination during placement as one of the most common causes of cement plug failure.
One service company with extensive experience operating in the North Sea has used a model that integrates design and planning combined with a structured, detail-oriented process workflow to reduce surface execution and downhole placement risks thereby increasing the chances of success. The model relies heavily on close cooperation between the service company and the operator. Following the same strategy, this model can be applied in other geographical environments with the core objective of improving quality ensuring the job is always done right the first time. Some case histories, which inspire confidence in the ability to sustain the success rate, are described in this paper.
A Case Study on Compositional Reservoir Simulation for a Large Tight Reservoir: A Detailed Road Map from Initialization and History Match to Prediction Simulation
Authors: Basioni Mahmoud , Saad Mohamed A. , Dawoud Ahmed , El Mahdi Ahmed 
Published: February 2012

Abstract
This paper illustrates a detailed workflow to build a compositional simulation model for a large gas-bearing with a sizable oil-rim carbonate reservoir in the Middle East. The workflow is emphasising on the importance of data gathering, validation, analysis and integration in building a sound simulation model from geological and dynamical perspective. One of the main achievements of this work was the concept behind matching the variable producing Gas-to-Oil ratio without jeoporadizing the match of other performance parameters. The key resolution to this problem is the careful setup of equilibration and fluid models.
Integrated Approach: Key to Improved Reservoir Model
Authors: Tiwari Sanhita , Sathe Swati 
Published: February 2012

AbstractAn integrated approach where information and analysis from each discipline like geology, seismic, petrophysics and reservoir engineering is applied to build three-dimensional (3D) geo-cellular model and finally simulating the reservoir to represent the real flow conditions leading to formulate the field development strategy.Most of the present workflows are designed to model the clastic reservoirs integrating geological trend and statistical methods effectively. Limestone formations are highly sensitive to fluctuations in temperature, salinity and bathymetry which affect secondary porosity and permeability within the formation and thus result in randomness. Generally, in limestone the integration of geology and geo-statistics is very difficult due to lack of well defined geological trend or randomness. This difficulty is further enhanced if the wells available within the study area are few. Paper brings out how use of seismic derived porosity trend during property modeling led to a meaningful porosity model in a limestone reservoir. In absence of core based J-function data, use of log derived initial water saturation helped in deciding the rock type distribution and saturation modeling capturing the transition zone observed in wells. Classical methods like WOR & WOR derivative plots and material balance study helped in deciding the type of aquifer support and oil volume in place. The paper deals with a real case example of a carbonate reservoir in an offshore environment with around 12 MMT oil in place and 3 exploratory and around 9 development wells within the study area. Finally, with the help of a real case example, the paper brings out the critical stages where the application of integrated approach leads to an improved reservoir model which gives reasonably good estimate of the oil in place and a satisfactory history match.
A Study of the Behavior of Oil Spill from an Offshore Rig in Red Sea Region
Authors: Shehadeh M.. , Elsayed T.. , Youssef M.. , Al Ashkar G.. 
Published: February 2012

Abstract
Oil spills due to various industries including commercial shipping and offshore platforms damage the near coastal zones, ecological life, and tourism areas. Hence, it is required in many countries to develop oil spill contingency plans in compliance with the Oil Pollution Act of 1990 (OPA) and/or the Offshore Continental Shelf Lands Act (OCSLA). Implementation of the International Convention on Oil Pollution Preparedness, Response and Co-operation (OPRC) Convention and related issues are important elements of the IMO's Integrated Technical Co-operation Programme. The risk assessment/management, development of national contingency plans, environmental sensitivity index mapping, establishment of regional and sub-regional preparedness and response systems (agreements, plans and centers) and advice on dealing with marine pollution incidents are requested. This paper presents simulation results using a simulation model for studying the behavior of oil spill from an offshore rig. The model possesses a general structure that can accommodate most of the remaining weathering processes and a number of hypothetical scenarios are simulated for Red Sea region. The results show that using simulation can improve the oil spill contingency plans to support a risk-based decision which prevents future fatal accidents.
Potential Implementation of Casing while Drilling Technique in the Western Desert Fields of Egypt
Authors: Fattah K. A. , Sinde Seydou , Dahab A. A. 
Published: February 2012

AbstractCasing While Drilling (CWD) technique allows the operator to simultaneously drill and case a wellbore section in only one run without the necessity to pull the drill string out of the hole. This innovative technique comes into play in time when oil and gas well drilling faces a lot of challenges such as excessive lost circulation, formation fluid influx, formation instability, etc. CWD is implemented into today drilling activities in order to safely and economically deal with these obstructive challenges. In addition to eliminating/minimizing the effects of these challenges, it remarkably improves the entire economics of the drilling project. Researches and developments are continuously on their ways to further improve the performance of the technique in order to minimize its limitations. A lot of case studies all over the world have been analyzed and their related practical lessons have been stated. Based on a study carried out on five shallow wells and seven deep wells drilled between 2007 and 2008 in the region of Western Desert, lost circulation and stuck pipe represented more than 80% of the drilling problems. The study revealed that CWD could be an alternative approach in the region to eliminate/minimize the aforesaid problems as was the case in numerous fields in the world. Therefore, the potential applicability of CWD technique in the region has been widely discussed. A proposed drilling program that suits CWD has been given. Special reference has been also given to casing string design, mud program, hydraulics optimization, bit selection criteria, working conditions and operational parameters such as WOB and RPM.
Challenge in Mature Field's Waterflood Project: Facing Limited GGRP Data & Budget Issue
Authors: Handayani Nuni , Simamora John H. 
Published: February 2012

Abstract
In the middle of high demand of oil production, Pertamina EP faces the fact that most of the fields are mature fields that sharp declining production rate is inevitable. This condition should be followed by other production method alternative because primary recovery is no longer be solution to increase production or restrain production decline. The option to this condition is moving to secondary phase: Waterflood.
EOR Department (team) performed screening analysis to find suitable candidates for the waterflood. Tapian Timur Field was one of the candidates. This field has a good potential to waterflood development but also has a huge constraint to be faced. Some constraints were the lack of GGRP Data, no existing water source, limited facilities and foremost was limited development costs. The challenge to develop waterflood project in this field is how to conduct project that meets engineering and economic aspect.
Tapian Timur Field's Study and Evaluation was carried out to evaluate Geology, Reservoir and Production in integrated way to determine: layers to be injected, injection patterns, sources of injection water, etc. The team also conduct comprehensive studies of production facilities. Due to budgeting issue, this project design emphasizes to maximally use existing wells and facilities. This could reduce costs significantly.
Waterflood was successfully conducted in layer C in May 2010 that preceeded with pilot waterflood. Pilot waterflood showed a good response indication. Currently the team is preparing POD (Plan Of Development) regarding to Tapian Timur Full Scale Waterflood Project.
Modeling Inflow Performance Relationships for Wells Producing from Multi-Layer Solution-Gas Drive Reservoirs
Authors: Qasem Fuad , Malallah Adel , Nashawi Ibrahim Sami , Mir Mohammad Irfan 
Published: February 2012

Abstract
Optimum field development strategy requires good knowledge of anticipated well performance and future flowing condition variation. This practice involves continuous monitoring of surface facility network, wells, and reservoir. Thus, it is crucial for the petroleum engineer to possess the appropriate tools to efficiently forecast well behavior, design artificial lift equipment and stimulation treatments, forecast production, and improve the entire production system optimization. Inflow performance relationship (IPR) is one of the vital tools required to monitor well performance. Currently used inflow performance relationship models are idealistic in nature, mainly developed for homogeneous reservoirs, and not suitable for multi-layer systems with different permeabilities. Consequently, the available IPR relationships do not provide accurate performance of such reservoirs. Thus, there is an urgent need for new realistic IPR models that describe the actual reservoir inflow performance behavior more efficiently than t he available models.
This study investigates the effects of reservoir heterogeneity on IPR curves for wells producing from multi-layer solution-gas drive reservoirs. To achieve the desired objectives a stochastic simulation algorithm known as simulated annealing was used to generate various permeability realizations among the stacked layers. The generated data were then thoroughly scrutinized and two simple yet accurate empirical IPR models were developed for heterogeneous two and multi-layer solution-gas drive reservoirs.
Chemical Injection in Multilayered Reservoir that have Different Rock Properties and Pore Pressures
Authors: Ahmed Quosay Awad 
Published: February 2012

AbstractWell intervention techniques and several IOR and EOR methods are sometimes entailing injection of emulsion of water based chemicals and oil into hydrocarbon reservoir layers. The injection depth into each layer usually depends on a lot of different factors that related to reservoir rock and fluid properties as well as the difference between injected fluid's pressure and formation fluid's pressure. For a well completed in multi zones and each zone has its own permeability, porosity, fluid saturation and pore pressure; it is difficult to predict how and up to what end the injection fluid will invade each zone.A computation model, based on analytical equations of flow in porous media, is developed to simulate bullhead injection of water based chemical solutions into well with multi opened zones. Analytical equations are developed to model fluid penetration radius, injected volume and injection rate for every opened zone during the injection process. Equations describe cooling effect of the injected fluid into hot formation is arranged and simulated to illustrate radial and vertical cooled area during the injection process. An equation is developed to simulate dilution process of chemical concentrated solution during its injection into reservoir layerThis model is very useful when it comes to plan and to design chemical water shut off, sand consolidation, microbial fluid placement, injection of mobility control fluids or any treatment involves of bullheading of chemical concentrated solutions into multi layered reservoir. It can be also used to design many workover applications especially for comminglely completed wells.
Modeling Flow of Chelating Agents during Stimulation of Carbonate Reservoirs
Authors: Mahmoud M. A. , Nasr-El-Din H. A. 
Published: February 2012

AbstractDifferent fluids have been introduced in the oil industry to be used as alternatives to HCl. Chelating agents such as EDTA (ethylenediaminetetraaceticacid), and HEDTA (hydroxy ethylene diamine triacetic acid) have been used as stand-alone stimulation fluids. These fluids can be used to stimulate water injectors, oil, or gas producers, therefore, the effect of the type of reservoir fluid on the stimulation process should be investigated.In this study, an analytical model was developed to describe the flow of HEDTA and EDTA chelating agents and propagation inside carbonate formations. The analytical model can be used as a pre-design tool before the treatments. The developed model can be used to predict the volume of the chelant solution required to create wormholes in calciteformations at different temperatures. The temperature affects the diffusion coefficient of the chelating agent, wormholing rate, and wormhole shape and size. The dissolving power of different forms of HEDTA chelating agent can be determined using the model. The optimum injection rate based on optimum wormholing conditions was identified for the chelating agents. Also, the model can be used to predict the wormholing rate of different chelating agents in carbonate formations.The analytical model can be used to predict the performance of the chelating agent in carbonate stimulation. The volume of chelating agent required to stimulate carbonate formation per foot thickness was determined using the developed model. The optimum injection rate was determined for different chelating agents using the model and the results were compared with experimental results from previous work and there was a good agreement between the measured and the predicted values. The model can be used to determine the best stimulation fluid based on the temperature and fracture pressure of the target zones.
Comprehensive Model for Flash Calculations of Heavy Oils Using the Soave - Redlich - Kwong Equation of State
Authors: AL-Jawad Mohammed S. , Hasan Omar F. 
Published: February 2012

AbstractOne of the main techniques to achieve phase behavior calculations of reservoir fluids is the equation of state. Soave - Redlich - Kwong equation of state can then be used to predict the phase behavior of the petroleum fluids by treating it as a multi-components system of pure and pseudo-components. The use of Soave – Redlich – Kwon equation of state is popular in the calculations of petroleum engineering therefore many researchers used it to perform phase behavior analysis for reservoir fluids (Wang and Orr (2000), Ertekin and Obut (2003), Hasan (2004) and Haghtalab (2011))This paper presents a new flash model for reservoir fluids in gas – oil separation stations. The proposed model uses Soave - Redlich - Kwong equation of state for calculating vapor and liquid mole fraction after each separation stage of heavy oils. The form of Soave - Redlich - Kwong equation of state that used in this paper is the cubic equation for Z-factor. The solution of this cubic equation depends on using Newton's and false position methods to find the three roots of the equation. This model finds the initial guess of Z-Factor using the false position technique and calculates the exact value of Z-Factor by applying the Newton-Raphson technique. The new model distinguishes between liquid and vapor phases through choosing the minimum root as the Z factor for the liquid phase and the maximum root as the Z factor for the vapor phase.Many empirical relationships have been applied to calculate the related parameters which are utilized to perform the flash calculation. AL–Dulaimy's correlation (2002) is utilized to calculate the critical properties for the plus fraction (C7+). Wilson's correlation (1968) is used to guess the initial value of equilibrium ratio. Whitson's correlation (1984) is employed for calculating boiling point for plus fraction (C7+).The new model has been tested using Iraqi oils data for several degasing stations. Calculated results of vapor mole fractions are found to be in excellent agreement with the field data. The graphical demonstration of the calculated results and field data shows credit index to utilize the new model in separation calculations of heavy oils under different temperatures. Two more Iraqi separation stations have been used to check the efficiency of the proposed model.