Properties Of Crude Oil Research Articles

Chemical and thermodynamic properties of palm oil-based materials and their impact on recycled binder blends

• We characterised chemical and thermodynamic properties of palm oil-based materials. • We assessed the impact of adding these agents to binder blends of an HMA with high RAP. • Surface free energy was used to assess the adhesion quality and durability of the bonds between aggregates and recycled binder blends with these agents. • Key chemical compounds present in the palm oil materials contributed to the rejuvenation effectiveness. • Palm oil-based materials are promising candidates to be used as rejuvenators in HMA with high RAP. Rejuvenators are agents added during the production of hot mix asphalts with high contents of reclaimed asphalt pavement (RAP) to restore some properties of the aged RAP binder. These materials can be obtained from numerous sources; hence, their chemical composition and physical properties vary greatly, which can have an impact on the final mixtures’ properties. This work assesses key chemical properties of crude palm oil and two of its solid by-products to understand their rejuvenation effect on a blend of a virgin and an aged RAP asphalt binder. The evaluation included thermogravimetry analysis (TGA), Fourier transform infrared (FTIR) spectroscopy and chromatography analysis. Besides, surface free energy measurements (SFE) on the recycled binder blends (i.e., virgin asphalt binder, RAP asphalt binder and rejuvenator) and of two aggregate sources were used to evaluate the impact of the palm oils in the adhesive bonds’ quality and moisture sensitivity of the recycled binder blends-aggregates systems. Results indicate that the palm oil materials have good thermal stability and contain several large molecular size (LMS) compounds that contribute to the rejuvenation effect. Besides, recycled binder blends produced with the palm oil materials developed strong adhesive bonds in dry and wet conditions. Overall, results highlight the potential of palm oil and its solid by-products as rejuvenators for high RAP content asphalt mixtures.

Effect of nickel oleate assisted ultrasonic waves on rheological properties of Tahe crude oil

The present study discussed the rheological changes of Tahe crude oil which were treated with ultrasonic waves and nickel oleate. The properties of crude oil such as freezing point, thixotropy, viscosity, flow pattern and viscosity-temperature dependence were tested and analyzed. In addition, SARA fractions, FTIR analysis and XRD patterns were applied to give detailed information on asphaltene structure. The results revealed that crude oil had high content of asphaltene and behaved as pseudoplastic fluid at low temperature. Ultrasonic waves can break the chain of asphaltene molecules which resulted in that asphaltene content decreased by 19.22% and light components content increased. In terms of macroscopic rheology, it can be seen that freezing point and viscosity reduced, thixotropy weakened, and rheological properties improved. After the addition of nickel oleate, the asphaltene content was further reduced by 31.67% through hydrogenation reaction. Meanwhile, the intermolecular interaction was reduced to inhibit the formation of gelled structure. As a result, the rheological properties of oil samples can be further improved.

Investigation on Wax Deposition Reduction Using Natural Plant-Based Additives for Sustainable Energy Production from Penara Oilfield Malaysia Basin.

In empowering the United Nations (UN) Sustainable Development Goal, the oil industry is inclined toward organic wax inhibitor applications when combatting the wax deposition issue during crude oil production. This is because synthetic chemical inhibitors are costly and have the potential to create environmental problems when oil spillage or seepage occurs during transportation or operation. This study evaluates the impact of low-cost, natural plant-based inhibitors such as Jatropha seed oil (JSO), crude palm oil, and crude palm kernel oil (CPKO) on paraffin inhibition efficiency (PIE, %) and rheological properties of Malaysian waxy crude oil. By using cold finger equipment and a Fann viscometer, the amount of solid wax deposits, apparent viscosity, plastic viscosity, yield value, and gel strength were determined. Commercialized ethylene-co-vinyl acetate and triethanolamine compounds were used for a comparative study. For the wax deposition test, the results revealed that the highest average PIE obtained was 86.30% when 5% JSO was blended with Penara crude oil. Meanwhile, the rheological test proved that 5% JSO and 1% CPKO were acting as highest viscosity-reducing agents at 60 °C below the wax appearance temperature (WAT). The discovery of palm-based and Jatropha-based inhibitors from Malaysia’s palm oil plantation and Malaysian JSO as a wax inhibitor was found to be beneficial for the application of wax deposition and rheological studies in crude oil production with a less harmful environment for sustainable energy production.

Effect of a Coated Wall on Wax–Asphaltene Molecule Diffusion, Aggregation, and Adhesion Mechanism: A Molecular Dynamics Simulation Study

Coating is increasingly used as a cost-effective strategy for controlling heavy component deposition in waxy crude oil transportation flowlines. This paper systematically investigated the micro influence mechanism of the coated wall on the diffusion, aggregation, and adhesion behavior of wax–asphaltene molecules by the molecular dynamics (MD) method. A set of experiments was performed to determine the properties of the waxy crude oil. For overcoming the limitations of the model simplification of previous MD studies, the MD models based on experimental data were developed to characterize the motion behavior of wax–asphaltene molecules on non-coated and coated wall surfaces, and the simulated densities of crude oil components had an error of less than 5% with the National Institute of Standards and Technology (NIST) data, which showed that the established model was accurate and reliable. The simulation results showed that two condensate oil layers were formed on the non-coated wall surface, the diffusion and aggregation behavior of wax–asphaltene molecules were enhanced under the low-temperature condition, and there was considerably heavy component molecules adhesion to the non-coated wall surface. The analysis of mean square displacement, radial distribution function, and relative concentration distribution revealed that 288.15 K was the peak wax precipitation, which was consistent with the experimental conclusion. It was also found that the presence of low surface energy coating weakened the diffusion of heavy component molecules. The epoxy silicone-coated had the weakest interaction with wax–asphaltene molecules. Moreover, the fact that the coated wall had a certain inhibitory effect on the aggregation and adhesion of wax–asphaltene molecules in the pipeline was proven, where the epoxy silicone-coated had the strongest inhibitory effect. These investigations present new insights and guidance for controlling heavy component deposition by coating in the pipeline transportation process of waxy crude oil.

Synthesis of copolymers based on maleic anhydride and α-olefins and modification with primary amines as pour point depressant (PPD) for waxy crude oils

Polymeric PPDs that reduce the pour point of crude oil are one of the most important chemicals utilized in the petroleum industry, especially when transporting waxy oil. The regulation of the structure of such polymers with different hydrophobic-hydrophilic balance makes it possible to select an effective PPD to improve the low-temperature properties of crude oil. On this basis, the current work presents a series of syntheses of copolymers based on α-olefins and maleic anhydride and their modification by the amidation reaction with primary amines: butylamine, hexylamine, hexadecylamine, octadecylamine, and benzylamine. The structure of the copolymers was determined through FTIR spectroscopy and 1H and 13C NMR spectroscopy. The molecular weight of the copolymers was identified by the method of light scattering. The study of the effect of modified copolymers on rheological behavior and lowering the pour point was performed for waxy crude oil from the Akshabulak field (Kazakhstan). Rheological tests have shown that the synthesized copolymers improve the fluidity of oil and reduce the values ​of the yield stress of oil. Optical micrograph showed that the modified copolymers form fine crystals of paraffins and exhibit dispersing properties.

Magnetically recoverable poly (methyl methacrylate-acrylic acid)/iron oxide magnetic composites nanomaterials with hydrophilic wettability for efficient oil-water separation

Due to the environmental and production problems of emulsion, it is important to efficiently separate oil-water emulsion to meet the refinery requirement and clean up oil spills. Synthesis of a universal demulsifier is not an easy task because the physical properties of crude oil vary, which makes its characterization and demulsification procedure difficult. To overcome this problem, hydrophilic and magnetically recoverable poly (methyl methacrylate-acrylic acid)/iron oxide magnetic composite nanoparticles ((P(MMA-AA)/Fe3O4 NPs) were developed as an efficient and economical demulsifier via soap-free emulsion polymerization. To characterize the magnetic composite NPs for their appropriate surface morphology and magnetic domain, TEM, FTIR, VSM, and TGA analyses were carried out. The newly synthesized NPs displayed good hydrophilic properties as they migrated quickly to the aqueous emulsion phase, which was also reassured by their water contact angle of 75°. They exhibit strong magnetic characteristics (20 amu/g) in the oil-water emulsion, makings the hydrophilic wettability capable and attractive to the external magnet. Experimental results revealed that the prepared magnetic composite NPs separated 99% of the water from stable emulsion in 30 min and could be recycled 8 times through magnetic separation. The recycled magnetic composite NPs maintain their hydrophilic wettability and efficiency in separating oil-water emulsion, making them economical and commercially viable. The migration of magnetic composite NPs to the aqueous phase in the stable emulsion with a strong magnetic domain explains the coalescence of emulsified water droplets and their quick separation from the stable emulsions through the external magnet.

Influence of heterogeneity on fluid property variations in carbonate reservoirs with multistage hydrocarbon accumulation: A case study of the Khasib formation, Cretaceous, AB oilfield, southern Iraq

Abstract The fluid distribution is considerably influenced by the reservoir homogeneity. This study analyzes carbonate reservoir heterogeneity and hydrocarbon accumulation processes in the Khasib reservoirs in AB oilfield in the Middle East to discuss factors controlling the distribution of fluid and the effects of this distribution on the productivity of single wells. The Khasib reservoirs in the AB oilfield show uniform vertical distributions, with a large difference in the longitudinal pore throats, and the upper part of the reservoir is better than the lower one. Because the hydrocarbon accumulation is multiphasic, the heterogeneity of crude oil is based on whether traps are formed in the early or late stage of source rock formation during accumulation. Moreover, the longitudinal physical differences in crude oil properties are mainly attributed to the longitudinal differences in the pore throats. The difference in the pore throat and physical properties of crude oil affords differences in the productivity of horizontal wells in different subzones.

Emulsifying stability and viscosity reduction for heavy crude oil in surfactant-polymer composite system

Heavy crude oil is one of the most precious and complex molecular mixtures available, with considerable economic relevance. Nevertheless, its high viscosity and complicated chemical compositions pose an exceptional challenge for viscosity reduction with a compound emulsification system in heavy oil exploitation. Here, two types of polymers were synthesized and compounded with surfactant SDS to reduce the heavy crude oil viscosity. Their emulsifying properties in demineralized water and mineralized water were measured to evaluate their differences from macroscopic views. Furthermore, the corresponding emulsion system (involving resins, asphaltenes, surfactants, polymers, etc.) was also simulated and computed using molecular dynamics simulation to investigate the relationships of various compositions on emulsifying properties at the molecular scale. The results showed that the surfactant-polymer composite system formed by the amphiphilic polymer had an obvious advantage in emulsifying stability with the water segregation rate of 60.6% after 48 h in the simulated salinity and the viscosity reduction rate reached more than 92.1% after optimization. Besides, the electrostatic interaction is the major part of the potential energy in emulsion systems at a ratio of 87.8%. The divalent cations (Ca2+ and Mg2+) resulted in the shrinkage or collapse of molecular conformation of the water-soluble polymer by 19%. The variation of interaction energy in salt solutions for different emulsifying systems caused a series of experimental and simulated distinctions, such as solution viscosity, interface behaviors, the number of hydrogen bonds, and the spatial distribution function, which ultimately determined the emulsifying properties of heavy crude oil. Notably, this work offers insight into the interactions and influences of complex mixtures in oil–water systems. It also facilitates to design and apply the innovative functional chemical additives in heavy crude oil extraction and transportation.

Intelligent Oil Production Stratified Water Injection Technology

As the driving energy to deal with the decrease of interlayer pressure caused by continuous oil production, the layered water injection technology has the characteristics of inhibiting the decrease of oil production and slowing down the increase of oil/gas ratio. In engineering, water injection technology is often used to improve the properties of crude oil, such as excessive viscosity, weak liquidity, and depleted storage, to avoid the formation of dead oil. Injecting appropriate amount of water into different production horizons can effectively maintain the formation water injection pressure, improve the sustainable development speed of the oilfield, ensure the oil production and effectively control the production cost. It is of great value to petroleum engineering and has been widely concerned by the industrial and academic circles at home and abroad. With the continuous development of oilfields over the years, most oilfields have become high-water-cut oilfields. Through the existing layered water injection technology, there are defects such as high labor cost, low operating efficiency, and long commissioning cycle. The ratio of water injection cost to constant increase gradually decreases, and the technical shortcomings become more and more obvious, which is difficult to meet production needs. It is urgent to study and optimize water injection technology scheme to meet oilfield production and technology iteration. In recent years, electronic technology, communication technology, automatic control technology, and other advanced production technology applied to geological exploration, logging technology fields such as engineering, oilfield development is towards integration and intelligent direction, which makes the advanced control and real-time communication intelligent power precision, and the layered water injection technology is possible. This paper summarizes the development history and status quo of oil recovery stratified water injection technology at home and abroad and points out that there are technical bottlenecks and development limitations in the development of water injection technology at present. Focusing on the current hot spots of intelligent oil recovery stratified water injection technology, the advantages and disadvantages of various intelligent water injection technology are compared and analyzed. It provides a certain theoretical reference value for the theoretical research and engineering application of intelligent stratified water injection technology to the equipment design and production of oilfield production and oil recovery technology research institutes and technology and equipment manufacturers.

Drag Reduction of AL-Ahdab Crude Oil Using Chemical Additives

The viscosity of crude oil has a crucial role in drag reduction during pipeline transportation; hence additives are required to enhancing the flow properties of AL-Ahdab crude oil. In this work, the potato starch biopolymer and CTAB surfactant are utilized to achieve the target. The drag reduction experiments were carried out at different crude oil flow rates (20-35-50 liters/min), pipe diameters (0.5-0.75 -1 inch), and different concentrations of potato starch (500-2000 ppm) and CTAB (100-500 ppm). The results showed that these additives had minimized flow resistance in various operating conditions, the drag reduction percent increased with increasing of additives concentration increase. The maximum drag reduction achieved using CTAB and potato starch is 41.6% and 36.3%, respectively, at 50 liters/min and 1-inch pipe diameter.

Neural network supported flow characteristics analysis of heavy sour crude oil emulsified by ecofriendly bio-surfactant utilized as a replacement of sweet crude oil

The present study was carried out to assess the replacement of the sweet crude oil (SWCO) with the natural additive surfactant (NAS) namely Madhuca latifolia for the emulsification of heavy sour crude oil (SOCO) in order to facilitate eco-friendly transportation. In this study, the flow characteristics of SOCO were investigated with and without emulsification with SWCO and NAS. Both additives were blended in 10 to 15 percent (by volume) in heavy sour crude oil. The rheological properties of the SOCO suspension were measured by a rheometer ranging from 0 to 500 s−1 for shear rate ranges. The temperature scale was taken as 32±9 °C throughout the investigation. The rheological properties of sour crude oil including steady-state behavior, yield stress, viscosity, thixotropic properties, and other non-uniform steady characteristics were studied during the experimentation. Dynamic light scattering and optical microscopy were employed to investigate the morphology and the distribution of the wax in the SOCO and its emulsions. The flowability of SOCO and its emulsions was evaluated by Fourier transform infrared spectroscopy i.e. FTIR. The flow properties of SOCO were found non-Newtonian at low temperatures and its viscosity was decreased with an increase in temperature. Rheological results demonstrate that the addition of Madhuca latifolia and SWCO caused a reduction in the viscosity of SOCO. However, the viscosity of SOCO was decreased more by the emulsification with Madhuca latifolia as compared to SWCO. However, the CC, CH, and CO bonds are disintegrated in the presence of the Madhuca latifolia functional group.

Asphaltene aggregation and deposition in pipeline: Insight from multiscale simulation

Understanding the colloidal structure of crude oil in pipeline is of great significance for finding effective solutions to remediate and prevent the aggregation and deposition of asphaltene during transport process. Here, combing large-scale structural-unit-based dissipative particle dynamics simulations and all-atom molecular dynamics simulations, the colloidal structure and interatomic interactions of crude oil in the pipeline are studied. The analysis of structural characteristics of asphaltene aggregates demonstrates that temperature, pressure, and flow speed jointly affect the colloidal structure of crude oil at mesoscopic level and the compactness of asphaltene aggregates at microcosmic level. By analyzing the mesoscopic structural properties of crude oil during transport and the microscopic interaction between crude oil and Fe2O3, the competitive adsorption of crude oil components on pipeline surface is demonstrated. We reveal that although the fluid movement of crude oil is favorable for structural transformation of asphaltene aggregate from large size to small size in bulk phase, but the asphaltenes are steadily deposited onto pipeline surface with the exfoliation of other oil components. These findings provide a molecular-level understanding of the colloidal structure of asphaltene during transport of crude oil through pipeline.

Wax precipitation and deposition risk: Issues on ethics and professionalism

The deposition of wax on pipelines causes problems that affect oil production rate and the facilities. Several preventive and control measures were employed to manage this problem. However, there is no single technique that is hundred per cent effective for different fields. Therefore, this article provides new interpretation of the associated risk of the problem – such as the impact of ethical and professionalism on wax deposition. It sheds more light on the need for the implementation of sound engineering practices during pipeline design, construction, and operations to reduce wax deposition risks and the associated remediation costs. The laboratory case study revealed that crude oil properties (such as wax appearance temperature (WAT), pour point (PP), and density), standard operating conditions and procedures must be accurate and continuously updated throughout the production life cycle. The results showed that maintaining crude oil temperature above wax appearance temperature (30°C) and at a relatively high flow rate particularly within the turbulent flow region (7, 9 and 11 l/min) provides a safe and uninterrupted production of waxy crude oil (δwax ≈ 0 mm).

Utilizing Attapulgite as Anti-Spill Liners of Crude Oil

The efficiency of attapulgite liners as anti-seepage for crude oil is examined. Consideration is given to the potential use of raw attapulgite and mixture attapulgite with prairie hay and coconut husk as liners to prevent crude oil seepage. Attapulgite clay used in this study was brought from Injana formation /Western Desert of Iraq. Two types of Crude oil brought from Iraqi oil fields were used in experiments; heavy crude oil from East-Baghdad oil field and light crude oil from Nassiriya oil field. Initially the basic properties of attapulgite and crude oils were determined. The attapulgite clay was subjected to mineralogical, chemical and scanning electron microscope analyses. Raw Attapulgite 150µm, 75µm, and 53µm were tested as anti-seepage liners for heavy and light crude oil. Experiments showed that raw attapulgite liners 53µm and 75µm are good in terms of retention and prevention of seepage so they can be used as the main layer to impede the flow of heavy crude oil. Raw attapulgite150µm could not be used as a liner to impede the flow of crude oil. This type of liner is totally inefficient for heavy and light crude oil. Adding prairie hay to attapulgite 150µm gives a good barrier medium that retains heavy crude oil and prevents it from seepage as long as possible. Raw attapulgite liners failed to prevent light crude oil seepage whereas the partial substitution of attapulgite by prairie hay or coconut enhanced the performance of the liner. Moreover, the addition of prairie hay with coconut to attapulgite enhanced the performance of the liner to a greater extent compared to raw attapulgite liners and mixture liner attapulgite with prairie hay.

Predicting crude oil properties using fourier-transform infrared spectroscopy (FTIR) and data-driven methods

Two data-driven approaches based on the Fourier-transform infrared spectroscopy (FTIR) data are presented in this work to predict crude oil properties. The first approach is the combination of the principal component analysis (PCA) and the support vector regression (SVR), namely PCA-SVR. In the PCA-SVR, the PCA is employed to extract the high-dimension FTIR data to obtain lower-dimensional data. The lower-dimensional data is utilized as the inputs of the SVR to predict crude oil properties. The second approach is a hybrid model composed of the autoencoder and the SVR, namely Auto-SVR. In the Auto-SVR, the autoencoder is exploited to learn new representations for the dimensionality reduction of the FTIR data. The learned lower-dimensional representations are input into the SVR to predict crude oil properties. The presented data-driven approaches are used to predict fractions of light virgin naphtha (LVN), heavy virgin naphtha (HVN), kerosene (Kero), distillate, vacuum gas oil (VGO), and residual in crude oil. According to the obtained results, the presented methods can achieve accurate predictions with satisfactory prediction accuracy.

Modification of the viscosity of extra-heavy crude oil using aqueous extracts of common geranium (Pelargonium hortorum)

The transport of extra-heavy crude oil is a severe problem in the oil industry due to its viscosity, asphaltenes content, and tendency to precipitate. These crude oil's characteristics cause clogging of the pipes and increase production costs. One of the solutions for this problem is the addition of compounds that reduce the viscosity of crude oil and the self-aggregation of asphaltenes. In recent years, new ‘green’ additives have been investigated to replace the use of traditional and more toxic substances, such as toluene. In this study, new common geranium (Pelargonium hortorum) aqueous extracts were synthesized with 1, 5, and 10% (w/v). Its effect on the Mexican extra-heavy (8 °API) crude oil blend was analyzed in a shear rate range of 0.1–60 1/s and constant temperatures of 30, 40, and 50 °C. In addition, its pH, TDS, and EC were measured on days 1 and 15 after synthesis. These synthesized compounds were qualitatively determined using phytochemical analysis. The possible relationship between these compounds and the viscosity modification was analyzed. The results suggest that using these compounds as viscosity modifiers for extra-heavy crude oil could be promising, at higher concentrations in the range of 5–10% and for a temperature range of 40–50 °C, and for lower shear rates. The conclusions suggest further investigation of the common geranium aqueous extracts to understand its effect on crude oil properties.

Improved generalized regression neural network for quantitative analysis of crude oil density by gas chromatography

在油气勘探开发领域,快速识别储集层原油性质对于工程技术人员有非常重要的指导意义。地球化学录井技术是用于判断储集层原油性质的常规手段,能为储集层综合评价提供专业认识。该文研究了地化录井中的岩石热解分析和气相色谱分析的原理,提出了一种利用色谱谱图对原油密度进行定量分析的新方法,再结合原油性质密度划分标准,可快速判断储集层原油性质。首先使用计算机图像处理软件对色谱图进行标准化和归一化预处理,并分析了岩石热解气相色谱谱图的曲线特征规律,提出了岩石热解气相色谱谱图的特征参数提取方法,将色谱图转换为特征参数矩阵。其次,研究了3种人工智能预测分类模型,为了适合该实验对储集层原油密度的预测,对其做了部分优化改进,利用元启发式优化算法(麻雀搜索优化算法)对广义回归神经网络的超参数进行了优化,提高了模型的精度和收敛速度。最后,通过现场获得的气相色谱图样本对各模型进行训练并验证,综合对比3种模型预测的结果,发现基于麻雀搜索算法优化的广义回归神经网络预测模型效果最佳,模型稳定,预测密度误差小,可泛化能力强。该研究所提出的方法能为储集层的综合评价研究和现场施工提供可靠的数据支撑。

Investigation of crude oil properties impact on wettability alteration during low salinity water flooding using an improved geochemical model

In low-salinity water flooding (LSWF), modifying the injected brine composition leads to greater oil recovery from carbonate reservoirs. The processes that control improved recovery during LSWF are not totally clear, which could lead to ambiguities in finding optimum brine composition regarding wettability alteration (WA) toward water wetness. One of the methods to determine WA is bound product sum (BPS) calculation using geochemical tools. In the case of wettability improvement, the BPS value of a crude oil-brine-rock (COBR) system should be at its minimum value. In this study, an improved geochemical model is developed, which includes the effects of oil composition (i.e., acid number, base number, and weight percent of nonhydrocarbon components) and physical properties of oil (i.e., density, viscosity, and solution gas-oil ratio) on COBR interactions. The proposed method generates BPS as a function of temperature, pressure, oil and brine composition, and pH for carbonate rocks. The model applicability was validated using several experimental data sets available in the literature. The results of the improved BPS model were in line with the results of contact angle and zeta potential measurements as the major indices of rock wettability. BPS calculations using the available geochemical tools sometimes failed to predict the correct WA trend since they overlooked the impact of oil properties on COBR interactions. The model predictability was also compared with the results of an available geochemical tool, PHREEQC, and the results demonstrate just how important the effect of oil properties and composition inclusion on wettability determination is. The improved BPS approach could be successfully utilized as an optimization tool to optimize the water composition during LSWF for a given COBR system.

Study on layer system complementarity technology in Block N

In view of the low permeability of oil reservoir, poor physical properties of crude oil, narrow strip development of channel sand, scattered development of plane sand body and serious heterogeneity in block n, there are some problems in water drive development, such as low well pattern control, low oil production rate, fast water cut rise rate and large production decline, the ideal stimulation effect can not be achieved by conventional measures, which restricts the potential of the block. In block n, 9 water injection wells and 16 production wells are selected to carry out layer series complementarity. Through the layer series complementarity of infill wells and basic well pattern, the well spacing is reduced, the injection production relationship of narrow sand body is improved, the water drive control degree and multidirectional connectivity ratio are improved, and the feasibility of improving the water drive development effect of block n is improved. In this paper, through the analysis of various remaining oil distribution types, the hole filling mode is optimized, so as to obtain better social and economic benefits.

Integrated Approach Improves Completion Reliability Using Compact Horizontal Wellhead

This article, written by JPT Technology Editor Chris Carpenter, contains highlights of paper IPTC 20201, “Improving Completion Reliability by Integrating ESPs, Intelligent Completion, and Zonal Downhole Monitoring With a Compact Horizontal Wellhead,” by Suresh Jacob, SPE, Maithem Al-Nakhli, SPE, and Muhammad Munir, SPE, Saudi Aramco. The paper has not been peer reviewed. Copyright 2020 International Petroleum Technology Conference. Reproduced by permission. The complete paper presents an oilwell completion integrating multilaterals, intelligent completions, permanent downhole monitoring systems, electric submersible pumps (ESPs), and a horizontal wellhead system. The paper discusses the completion drivers and design, individual equipment, preparation, field experience during installation, and performance of the system during production. The completion has been installed successfully and its lessons are being applied in the design of future installations. Background The well was drilled in a field comprising two main stacked reservoirs separated by a thick nonporous impermeable mudstone barrier. The two reservoirs are in an asymmetrical anticline structure sharing the same oil/water contact. The two reservoirs have a common pressure gradient and similar crude oil properties while having different petrophysical properties, with one reservoir having twice the productivity of the other. Both reservoirs were developed simultaneously using peripheral water injection with horizontal injector and producer wells. Dedicated producer and injector wells targeting individual reservoirs were drilled because of the differences in productivity and the areal extent between the reservoirs. ESPs were installed in all producers to increase rates and to transport fluid to surface facilities. Multilateral wells were drilled to increase production rate and to decrease pressure drawdown. These wells were drilled as TAML Level 2 wells, with openhole laterals drilled from a cemented liner. An intelligent completion allowed the production from each lateral to be controlled remotely from the surface. While both ESPs and intelligent completions are widely used in the industry, the integration of these technologies in the same well is rare because of the difference in operating cycles for the two systems. A well with both ESPs and intelligent completions should be designed to allow periodic ESP workovers while retaining the intelligent-completion equipment within the wellbore for the life of the well. The downhole-disconnection tool is a key enabler in the integration of ESPs and intelligent completions. However, the high level of operational planning and precision required to reconnect the control lines after ESP workover and the absence of downhole sensors in the intelligent completion prompted the design of an ESP/intelligent-completion integration without the downhole wet-connect tool.