bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Weak Alkali ASP Flooding Research in High Water Cut Shallow Reservoir
Authors: Gao Ming , Luo Wenli , Zhang Shanyan , Zhang Qun , Shi Yanyao , Sang Guoqiang , Ji Zemin 
Published: October 2018

Abstract
Strong alkali ASP flooding is now the major choice to develop high permeability reservoirs after water flooding in China. The formation was damaged seriously by the component of alkali. Weak alkali ASP flooding technique has become one of the most important research fields in EOR method due to the prevention of side-effects of alkali.
The Laojunmiao oilfield has been developed 79 years since 1939. The waterflooding's ineffectiveness was caused by complex reservoir structure and longtime water flooding. The waterflooding remaining oil distribution of Laojunmiao reservoir was analyzed by sealed cores, logging interpretation, fluorescence analyses, numerical simulation and other means. The appropriate EOR technology of high water cut shallow reservoir was selected by laboratory experiments, numerical simulation and single well test. In order to avoid formation damage and protect environment, weak alkali ASP flooding was chosen as the candidate EOR method.
The recovery factor of sand body type I and II (high permeability) were higher than type III and IV (low permeability). The main remaining oil type was oil membrane at the particle surface. Membrane remaining oil major distributed at the rock surface between the large grain holes (greater than 10 microns), which was suitable for ultra-low interfacial tension chemical flooding technology. The weak alkali ASP flooding injection parameters were identified by indoor natural core experiments and numerical simulation parameter optimization. Due to the low fracture pressure of shallow reservoir, the pressure rising space of weak alkali ASP was just 1-3MPa. It was necessary to choose the appropriate injection speed, realizing injection pressure control, which avoided dynamic cracks forming. The pressure rose from 4.9 MPa to 7.65 MPa during single well injection test. 6 months later, the water cut of effective wells decreased to 81.3%, the injection system was suitable for Laojunmiao oilfield. The injection process and equipment requirements of weak alkali ASP are simple, which has less effect on the environment.
The weak alkali ASP flooding of this paper is different from the conventional chemical flooding, which will provide the necessary support for future applications. The strong alkali ASP flooding will be replaced by weak alkali ASP flooding in the future.
Formation Damage Assessment and Adsorption/Desorption Profile of New Phosponate-Based Scale Inhibitor at 350°F
Authors: Al-Aamri Jamal , Al-Dahlan Mohammed , Al-Yami Ibrahim , Hazzazi Hassan 
Published: October 2018

Abstract
The formation of calcite scale is induced generally through a change in pressure and temperature, which affects the saturation level of calcium and bicarbonate as the CO2 gas is released. Prevention of calcite precipitation through scale inhibitor squeezing job treatment is a well-known method for minimizing potential scaling. The selection of suitable scale inhibitor is important as its performance can be affected by the lithology and reservoir conditions. In this study, a scheme of screening new scale inhibitors was evaluated. The proposed scheme included the study of the adsorption/desorption characteristics of the scale inhibitor and its efficiency at higher temperature.
The proposed scale inhibitor treatment design included pre-flush/post-flush fluid and the SI main fluid in addition to the synthetic formation water (SFW). Lithium chloride was introduced to the main SI fluid as a tracer.
To study the SI fluid-rock interaction, core flood testing was conducted on the Outcrop Torrey Buff sandstone core plug. The results of the core flood was used to determine the change in permeability during the SI soaking and assess the formation damage. Ca, Mg and total iron in the effluents samples were used to study the dissolution of the plug. P and Li analysis were used to study the absorption/desorption behavior of the scale inhibitor during the 5 days of flooding and compared to the minimum inhibition concentration (MIC).
Core flood data showed the differential pressures versus the cumulative pore volume of the injected fluids revealed that around 20% of formation damage was encountered during the SI flooding, which is anticipated in sandstone rock due to high adsorption of the scale inhibitor on the rock. The desorption profile of the scale inhibitor showed that the proposed treatment scale inhibitor could keep its concentration above the MIC at ultra-high temperature.
The study revealed that the proposed phosphonate-based inhibitor showed effective performance at higher temperature. The desorption rate is adequate to keep the scale inhibitor concentration above the MIC. The scheme of study can be used to screen different scale inhibitors at higher temperature and to assess their adsorption/desorption characteristic.
Investigation of the Relationship Between Rate of Penetration and Mud Weight Based on the Hardness of the Rock
Authors: Alkinani Husam H. , Al-Hameedi Abo Taleb , Dunn-Norman Shari , Flori Ralph E. , Hilgedick Steven A. , Alkhamis Mohammed M. , Alshawi Yousif Q. , Al-Maliki Madhi A. , Alsaba Mortadha T. , Amer Ahmed S. 
Published: October 2018

Abstract
The rate of penetration (ROP) plays a major role in drilling optimization, making it an important area of investigation. In this work, sensitivity and statistical analysis were carried out using data from over 100 wells in the Rumaila field, Iraq. The goal is to assess the effect of mud weight (MW) on ROP, to provide a method for estimating the recommended range for operational mud weight based on the hardness of the rock.
Drilling intervals from data collected from drilling reports from over 100 wells in the Rumaila field, Iraq, were categorized as weak, medium, hard, and very hard, based on UCS, depth, and lithology. Statistical and sensitivity analysis was conducted, developing correlation coefficients (CC) to represent relationships between rock hardness, ROP, and MW from field data. This methodology combines data from mud logging, daily drilling reports, and geological information to investigate the relationship between ROP and MW for different rock types and strengths.
It is well known that MW can dramatically impact ROP, and well documented in literature and laboratory studies. Several early studies focused directly on MW, clearly demonstrating the effect of MW on bit conditions, and therefore ROP. However, these studies do not include consideration of the hardness or lithology of the rock. There is also a strong discrepancy between results from different studies. Different literature concludes the relationship between MW and ROP is inverse, and in some it is direct.
For this study, field data have been gathered (more than 100 wells) to further investigate the relationship between MW and ROP, and how it varies with rock hardness. Field data have been categorized based on the hardness of the rock. The results showed that MW has an inverse relationship with ROP for the weak formation with a CC of -0.57. Thus, MW should be maintained as minimum as possible when drilling through the weak formation. On the other hand, MW has a direct relationship with ROP for medium, hard, and very hard formations with CC of 0.31, 0.4, and 0.42 respectively. Hence, MW has to be maintained as high as possible to maximize ROP for medium, hard, and very hard formations.
Large-scale collection and interpretation of field data were collected to demonstrate the effects of MW on ROP with varying rock hardness and lithology. While field data of this scale is inherent of interest, this analysis also investigates relationships previously unexplored and extends understanding of how MW effects ROP.
Survey of Big Data New SQL Database Systems for Real-Time Data Transfer in the Upstream Oil and Gas Industry
Authors: Djamaluddin Basirudin , Mohammed Salahadin 
Published: October 2018

Abstract
In less than a decade, there has been a tremendous evolution in the various storage solutions used to contain wellsite data in the upstream oil and gas industry. Many organizations from wellsite data management providers to the oil and gas operators themselves are moving away from traditional relational database management systems (RDBMS) and towards big data solutions.
There are several reasons for this evolution. First, data flow has increased at an unprecedented rate as the number of rigs increase and so has the data frequency rate. Second, the types of data from the sensors and data acquisition systems (DAQ) have also grown. Third, for data analytics that requires high-speed processing, it needs to be received in a timely manner so insights can be drawn for better, faster decision- making.
Big Data implementation known as NoSQL databases were proposed to handle conditions where: the data volumes are increasing exponentially, various types of data that are being transmitted or connected from various sources which are substantial for data analytics, and the last is the high-velocity streaming data that requires high-speed processing.
Moving in this direction is not without sacrifice. For example, companies adopting NoSQL give up several important factors, for instance, how the database handles transactions from multiple applications. Implementing NoSQL means giving up the benefits of Atomic, Consistent, Isolated and Durable (ACID). NewSQL comes as a promising new solution which offers the same scalable performance as NoSQL for the Online Transaction Processing (OLTP) read-write workloads while still maintaining ACID guarantees for transactions.
This paper will investigate, characterize and analyze the list of NewSQL databases in depth and develop comprehensive taxonomy for various critical aspects which come with them. We then will map the requirement of the data storage for handling upstream data to the proposed taxonomy so it can be used as a basis for analyzing each of the databases. At the end, we will predicate and highlight sorted databases which can be recommended for the implementation of next generation wellsite data storage in the upstream oil and gas industry.
Compatibility of Acid Precursors and Solvents with Sandstone Formations
Authors: Al-Ibrahim Hussain , Al Moajil Abdullah , Al-Yami Ibrahim , Al-Darweesh Sajjad 
Published: October 2018

Abstract
Organic acids and their precursors have been used to remove filter cake created by water or oil-based drilling fluids. Solvent and emulsifying surfactants are incorporated in the fluid recipe to solubilize oil residue and water-wet the surface of filter cake. Acids lost into the formation may interact negativity sandstone formation minerals and clays. The objective of this study is to assess fluid/rock interactions using high permeable sandstone core plugs.
Oil-based drilling fluids were used to create the filter cake. Formic and acetic acids-based fluid recipes were used at concentrations below their solubility limits. Mutual solvents and microemulsifying surfactants were added to the acid recipes to dissolve the oil residue and water-wet the filter cake. Compatibility, HT/HP fluid loss and coreflooding experiments, were conducted using the acid/solvent based recipes. Experiments were conducted at 250°F and 3,000 psi. XRD analysis was conducted to analyze solids generated after the reaction of sandstone core plugs with injected fluids.
Acetic acid-based fluid recipes were compatible with sandstone core plug. A Formic acid-based recipes showed a significant decrease in core plug permeability. XRD results showed presence of iron-based and calcium formate precepitations. Filtercake removal recipes showed effective removal efficiencies (e.g., 80-100 wt%).
The First Application of the Reinforced Thermoplastic Pipe in a Sour Wells in Saudi Arabia Gas Field
Authors: Bin Ziad Abdullah , Subaii Abdullah , Alshammari Fahad , Buali Muhammad , Fazaa Jamal 
Published: October 2018

Abstract
In a strive to reduce the domestic reliance on oil, Saudi Arabia continues to sustain and increase it is production of naturel gas by drilling and stimulating new gas wells in Gahwar field. The newly drilled wells by default will not have the required permanent surface equipment to flow the free gas and condensate to the gas plant during the testing process of the productivity of the well. This testing process may extend for days, particularly when the well undergoes fracturing stimulations where hundreds of barrels of stimulation fluids are pumped into the formation in high pressures to create artificial fractures into the pay zone to enhance the well productivity. Such operations require extended flowback periods to clean up the well in order to reach the required production fluid criteria. This paper will focus on the first successful application of the spoolable reinforced thermoplastic pipe (RTP) in Saudi Arabia gas field. A 10,500 ft of 4" high pressure-high temperature RTP line was temporarily spooled and connected from a newly stimulated well to a flowline of a pre exiting well which allowed to flow back a significant amounts of free gas and condensate to the gas plant. Testing separators were utilized during the flowback operation to insure a low water cut production to the gas plant. Challenges like large operating area, high H2s content, nearby oil and gas wells, the installation and dismantle process of the RTP line after completing the operation were faced and resolved during the implementation of this technology. Utilizing RTP during the testing period of the well saved the environment from unnecessary emissions of heat-trapping gases and is proven to be economically beneficial. However, it may not be possible to implement it in every well due to safety and geographical reasons.
Well and Layer Selection Method Study of CO2 Waterless Fracturing
Authors: Qinghai Yang , Siwei Meng , Tao Fu , Yongwei Duan , Shi Chen 
Published: October 2018

Abstract
CO2 waterless fracturing is a novel waterless fracturing technology. CO2 exists in the reservoir with supercritical state, and its fracturing stimulation mechanism is very different from that of water-based fracturing. This paper studies the physical and chemical properties of supercritical CO2 and reservoir adaptability of CO2 waterless fracturing.
Supercritical CO2 has the advantages of good fluidity and strong penetrability, which avail to form a complex network fractures. Through miscible phase with crude oil, absorption gas displacement, and reservoir energy enhancement, production and ultimate recovery are further improved. While the liquid CO2 has the disadvantages of poor proppant carrying capacity, high friction and low fracture opening. Based on CO2 waterless fracturing practices in Jilin oilfield, this paper summarizes physical parameters, operation effect and production situation of all wells, analyzes the main factors influencing productivity, and puts forward a set of well and layer selection methods of waterless CO2 fracturing.
Under the condition of existing CO2 thickening and resistance reducing technology, the selection of wells and layers is mainly carried out in 6 aspects. (1) Because the filtration of CO2 fracturing fluid is strong, the permeability of target reservoir should be lower than 5md in order to ensure stimulation effect of remote area. (2) CO2 can react with water and divalent metal ions to produce carbonate sediments to block existing pores and reduce reservoir permeability, so it is better for low water-bearing reservoirs. (3) Frictional resistance of CO2 is 1.9 times as that of conventional guar gum, so the target layer should be 3000m or shallower to reduce frictional pressure drop. (4) Energy increasing effectiveness of unit volume of CO2 is 1.9 times as that of slick-water, which is more suitable for stimulating undercompacted reservoirs. (5) There is no water phase in CO2 fracturing fluid, suitable for stimulating strong water-sensitive reservoirs. (6) CO2 is easy to dissolve in crude oil and greatly reduces its viscosity, which is suitable to stimulate heavy hydrocarbon reservoir.
Adopting above well and layer selection principles, CO2 waterless fracturing were implemented in 6 wells in 2017, and the key parameters, such as success ratio, sand adding amount, production capacity post-fracturing were comprehensively promoted, which effectively supported CO2 waterless fracturing development practices of unconventional reservoirs.
The Performance of the Popular PVT Correlations on Sudanese Crude Oils: A Statistical Study
Authors: Mohamed Abdelmjeed , Ahmed Musa , Mohamed Ismail , Abdein Moutaz 
Published: October 2018

Abstract
The knowledge of PVT properties is of a high importance in the petroleum industry, precisely, in oil and gas reservoirs development, engineering, and production. In the practice of petroleum industry, these properties are obtained by laboratory analysis from downhole fluid samples which are highly recommended to be taken in the early time of the reservoir prior to production to get representative reservoir fluid. It becomes a challenge when production is started as the fluid composition in the reservoir changes with changing the reservoir pressure, in such case PVT properties could be estimated using measured data on the surface separator, well head, offset field, etc. However, in many cases this data is not available and the only source to estimate these properties is the empirically derived correlations. In fact, there are many correlations that have been developed in the past seven decades for different geological areas. Nevertheless, these correlations are merely reliable for a specific range of data. Therefore, significant errors might yield when these correlations are applied for different regions and crude oils.
This work is the first regional and formal analysis that studies the performance of the most popular PVT correlations and introduces a new set of correlations that estimate some of the PVT properties of different Sudanese crude oils which are: bubble point pressure (Pb), solution gas-oil ratio (Rs), and oil formation volume factor (Bo), at pressures below the bubble point pressure.
The data was obtained from different Sudanese oilfields, to represent a wide range of data. Then, the data was analyzed, prepared and fitted with correlations using non-linear regression techniques. Afterwards, statistical analyses were performed, and the new correlations were compared with the existing correlations to prove their applicability using the most common statistical parameters, i.e. average absolute percentage error, standard deviation and R-square.
The Statistical Error Analyses (SEA) show that all the popular existing correlations yield a variable range of accuracy when these correlations are applied to our database and the proposed correlations were found to be superior to all the popular existing correlations in terms of accuracy when applied for this specific region. Eventually, the performance of the newly developed correlations was tested against each oilfield individually to ensure their accuracy, and it was found that the error varies widely from field to another.
It is concluded from this study that PVT properties vary regionally and recommendation comes to perform such study before using such correlations in estimating PVT properties for a specific region.
The Challenges and Lessons of Enhanced Oil Recovery Using Sequestrated CO2
Authors: Odesa David 
Published: October 2018

Abstract
The use of CO2 for enhanced oil recovery is a proven technology capable of increasing oil production and addresses energy security issues from known resources. In this work, we considered Carbon (IV) Oxide CO2 capture in a flowstation Mystras FPSO for re-injection in a 32km away depleted vertical Okono-3 Well in Okono field, Offshore Niger Delta. The study considered the screening of storage site, CO2 post-combustion capture using monoethannolamine (MEA), analytical determination of the minimum miscibility pressure (MMP), transportation and injection of captured CO2. The economics of the capture process and the risks of leakage over a long time were also considered. About 6.9433mmscf/day of CO2 will be captured annually and re-injected into Okono-3 well over a period of one year. With 9416ft as Point-of-Injection (POI) for CO2-enhanced oil recovery. CO2-EOR is a proven tertiary recovery technology which allows the recovery of an additional 10 – 20% of the original oil in place from depleted or marginal wells (Tzimas et al., 2005; Stevens et al., 2001).
Particle Swamp Optimization of PVT Correlation
Authors: Sylvester Okotie 
Published: October 2018

Abstract
Pressure-volume-temperature (PVT) properties are very paramount in the evaluation of oil and gas performance. They serve as input data in most reservoir engineering calculations such as material balance equation, reserve estimate, reservoir simulation/study. PVT properties are obtained from laboratory experiment by sampling the fluid and/or empirical developed correlations. Laboratory measurements of PVT properties are usually capital intensive and such are nor readily available during reservoir performance evaluation, hence, petroleum engineers resorted to using existing empirical correlations to generate these properties as the reservoir pressure declines. Often time, the PVT data obtained from empirical correlations do not agree with the experimental data, thereby yielding a considerable amount of error. Hence in this study, Standing’s correlation for estimating the solution gas-oil ratio and Kartoatmodjo and Schmidt correlation for estimating the formation volume factor were optimized using a particle swarm optimization algorithm to minimize the error associated in estimating these properties from experimental analysis at various depletion pressure. PVT data from differential liberation test was used to validate this study’s correlation and the result obtained shows that the optimized correlation for this study matches closely with the experimental values, also the newly optimized correlations was validated with other models and the results gave the least average relative error of 3.34 and a correlation coefficient of 0.998 after 216th successive iterations for the optimized Standing’s correlation and average relative error of ±0.00065 and correlation coefficient of 0.99996 after 154th successive iterations for Kartoatmodjo and Schmidt.