bluuebunny/crossref_metadata_2025 huggingface dataset:
Relevance of Ethnomuseology for Ethnographical Museums and Tribal Cultural Heritage
Authors:   Research Scholar, Indira Gandhi National Tribal University and Assistant Archaeologist, Archaeological Survey of India, New Delhi 110011, India., Prakash Kumar Om , Soni Amit ,   Assistant Professor, Department of Tribal Studies, Art, Culture & Folk Literature, Indira Gandhi National Tribal University, Amarkantak 484886, Madhya Pradesh, India.
Published: September 2022

Ethnomuseology is an interdisciplinary concept that mainly incorporates the Museum Studies and Ethnography / Anthropology with varieties of ethnic arts / artifacts. Ethnographical Museums all over world are the result of specialized field of Ethnomuseography. Since the initial stage and even till today Socio-Cultural Anthropologists are playing significant role to enrich the field of Ethnomuseography and contributing to the development of ethnographical museums in India and abroad. The present paper discusses about ethnographic museums in relation to tribal heritage of India in the wave of modernization and globalization. Most of the Ethnographic collections or cultural heritages are still prevalent in the form of living traditions. But, many of them are gradually lost or vanishing with time in the changing scenario due to cultural change. It is high time to preserve it by ethnomuseographical means. An attempt has also been made to discuss the ways through which such ethnographic museums are growing in India and abroad. In case of ethnographic museums especially community museums and tribal museums; Action Museology deals with the various aspects of tribal cultural sustainability and act as a key explanation to preserve and propagate the tribal cultural heritage.
Obstacles to Acquire Modern Medical Institutional Facility with Special Reference to Maternal Health Care among Tribals of South Bastar in Chhattisgarh
Authors:   Professor, School of Anthropology & Tribal Studies, Shaheed Mahendra Karma Vishwavidyalaya, Bastar, Jagdalpur 494001, Chhattisgarh, India,, Kumar Kolay Swapan , Chowdhary Siddharth ,   Professor, Department of Botany, Chaiytu Gayta (Alor) Government College, Pharasgaon, Kondagaon 494228, Chhattisgarh, India.
Published: September 2022

Introduction: The Maternal Mortality Ratio of Chhattisgarh is 269 (SRS 2010-11) which are higher than the National average (178). If we analyze the state wise data of MMR we found that Chhattisgarh is fourth in position amongst all states of India. Maternal and child health care is an important aspect of health seeking behaviour which is largely neglected among the tribal groups (Basu et al., 1990). It has been seen that inspite of a lot of government incentive programmes for women health care and development, some obstacles create obstruction to acquire modern medical institutional facilities. It is a burning concern for the development because the problems of tribal women differ from a particular area to another area owing to their geographical location, historical background and the processes of social change (Chauhan, A., 1990). Objectives: The study concerned with the objective of understanding the gap between government modern health facilities and tribal women with special reference to maternal health care. Study Area: For the study purpose tribal dominating villages of south Bastar, Chhattisgarh was selected. Chhattisgarh is known as 10th largest state of India where Bastar is known as its rich and uniqueness of bio-cultural diversity in the whole world. Methodology: Random sampling technique was the key instrument for selecting sample as well as Snowball sampling is also used to identify a few households where maternal and infant related problems occurred through some key informants in the village and ask each of them to identify households where maternal problems have occurred. Questionnaire on different variables of knowledge, attitudes, belief and opinion about government health institution were organised by direct interview. Along with above semi participatory observation was strength for the data collection. Result: The findings stated that the acceptance of modern institutional health facilities is poor amongst tribal people. In addition, a lot of females suffered from ill health due to pregnancy and childbirth in the absence of a well defined concept of health consciousness. Conclusion: The health problems of mothers arise as a result of synergistic effects of malnutrition, poverty, illiteracy, unhygienic living conditions, infections and unregulated fertility. Apart from that superstitious beliefs play an essential obstruction to acquire modern medical facilities. At the same time, poor infrastructure and ineffective public health services is also responsible for low inadequate obstetric care. Keywords: Maternal mortality; Seeking behavior; Modern medical institutional; Tribal women; Superstitious beliefs.
Mineral Formation at the East Pauzhetka Thermal Field (South Kamchatka) as an Indication of Influence of a Deep-Seated Alkaline Fluid and an Epithermal Ore-Forming System
Authors: Rychagov S.N. , Sandimirova E.I. , Chernov M.S. , Kravchenko O.V. , Sergeeva A.V.
Published: September 2022

—A sequence of argillized rocks and hydrothermal clays of the East Pauzhetka thermal field was studied in detail by means of drilling and trenching. We have identified zones composed of unusual mineral associations; their formation conditions are considered. The structure of the base of the hydrothermal-clay mass is shown. The source rocks (brecciated andesites) of the base are altered by hydrothermal–metasomatic processes and are represented by smectite–chlorite–K-feldspar–zeolite–carbonate–siliceous aggregate with sulfides, phosphates, titanium silicates and zircon silicates, and other mineral phases, including rare metals. A conceptual geological and geochemical model for the formation of argillisites and zones with mineral associations has been plotted. It is assumed that modern mineral formation in the East Pauzhetka thermal field inherits an epithermal ore-forming system located in the influence zone of a deep-seated fluid, the derivates of which are outflowing near the surface as alkaline metal-bearing solutions of the Pauzhetka hydrothermal system.
Surface-to-Borehole Electromagnetics Using an Array System: A Case Study for Co2 Monitoring and the Energy Transition
Authors: Strack Kurt M. , Barajas-Olalde Cesar , Davydycheva Sophia , Martinez Yardenia , Soupios Pantelis
Published: September 2022

Fluid imaging technologies are used in a wide range of E&P applications. Among geophysical methods, electromagnetics (EM) determines subsurface resistivities and thus responds to fluid changes. On the path to zero carbon footprint, the most significant potential for EM lies in monitoring geothermal, carbon capture, utilization and storage (CCUS), and enhancing oil recovery (EOR).

To optimize reservoir fluid monitoring, we calibrate surface measurements to well logs resulting in a 3D anisotropic model consistent with borehole data. This is done before and after depletion or injection to estimate a time-lapse reservoir response. As part of a carbon capture and storage project, we carried out baseline measurements and validated the surface EM data to the 3D anisotropic borehole model. The monitoring workflow for this project can easily be adapted for other applications to support the energy transition.

From this, we learned that measurement accuracy requirements higher than 1 % because we are often imaging small anomalies. While there are always limits in acquisition set by industrial noise, we derived two ways of increasing the anomaly. One is by using, similar to a borehole focused logs, focusing methods in the acquisition setup. This is still subject to measurement accuracy limitations and limited to electric fields only. Another way is to add borehole sensors that increase the sensitivity by around a factor of 10. While shallow (around 50 m) is sufficient, they can be extended to deeper borehole sensors, bringing the measurements close to the anomaly and is thus the preferred approach. This, in combination with calibration back to the 3D anisotropic borehole log allows you to certify the data for its information content. This will give you quantifiable ways to derive risk values and significantly reduce acquisition and monitoring operations cost.
Successful Reservoir Management and Optimization of Mature Steamflood Projects Using Artificial Intelligence
Authors: Popa Andrei , Lolley Chris , Munoz Juan , Luz Lozano Ramos , Angelo Chris , Lewis Kenneth , Lwin Al , Tirtawidjaja Alexia , Umbriaco Jacob
Published: September 2022

The reservoir management processes of heavy oil reservoirs are challenging and require different types of considerations when contrasted to conventional reservoirs. The development and optimization of heavy oil thermal EOR projects entails the injection of steam through dedicated injectors to assure the viscosity reduction necessary for the oil to freely flow thorough the porous media into the producing wells. The four stages of a steamflood development project consist of ramp-up, peak and plateau, decline and tail-end production. Optimization of each stage is critical for the success of the project.

The current study addresses the tail-end stage of the steamflood project and focuses on the optimization component of steam used, particularly steam reduction, within reservoir management practices. The novel approach presented in this work allows successful identification of mature areas within the reservoir and/or projects that are ready and would benefit from significant steam reduction. The methodology uses heat management knowledge, large datasets, and artificial intelligence (AI) technologies. The workflow exploits the log data, existing full-field earth model, the current steamflood conditions, and automates the screening and ranking of maturity of development patterns in large heavy oilfields.

The methodology outperformed the previous manual approach, not only by better identifying areas and opportunities, but also optimizing the steam reduction schedule, and in certain cases recommending steam redeployment to potentially increase field production.
Machine-Learning-Assisted Modeling of Diverting Agent Performance for Multiple Fracture Propagation
Authors: Chan Chin Hsiang , Furui Kenji , Mandai Shusaku , Kuwagaki Setsuka , Kanamori Yuuya , Hirano Yasuhiro
Published: September 2022

This study discusses the development of a diverting agent (DA) performance prediction model for simultaneous hydraulic fracture propagation based on numerical and machine learning approaches. The filtrate capacity of a particulate DA plug was quantified by the filtrate coefficient obtained from the analyses of past filtrate experimental data, with a parametric study performed to evaluate the influence of the filtrate coefficient on multiple fracture propagations.

We developed a wellbore-fracture coupled model that considered filtration by a DA for multiple hydraulic fractures. The proposed model solved flux redistribution and simultaneous fracture propagation after diversion. The filtrate performance of the DA can be adjusted and controlled by the filtrate coefficient. Furthermore, we developed a prediction model using a machine learning approach to evaluate the performance of the DA. The model was constructed using four different algorithms: MLP, SVC, RF, and AdaBoost, with each model evaluated and compared using five evaluation indicators. Furthermore, a feature importance analysis was conducted to assess the contribution of the experimental parameters employed in this study.

The numerical modeling results were validated against the analytical solutions for a plane-strain Khristianovic– Geertsma de Klerk (KGD) model. A series of numerical simulations were conducted to investigate the multi-fracture growth patterns under different filtrate coefficients during fracturing treatments. The parametric study showed that a DA based on Butane-diol vinyl alcohol co-polymer had sufficient filtration capacity, equivalent to that of ball sealers when the filtration coefficient was less than 10 [mL/min0.5], with almost no filtrate capacity when the filtration coefficient was over 1×10⁶[mL/min0.5]. As for the machine learning models, all models showed over 80% model scores; however, the RF and AdaBoost models, which are ensemble learning algorithms, provided better performance in terms of the five evaluation indicators compared to the other two models. Through the feature importance analysis, we calculated the contribution of each experimental parameter to the filtrate performance of DA.

The results of this study clearly demonstrate the influence of the filtrate coefficient on the diversion process. To the author's knowledge, this study is the first published paper to link the filtrate coefficient and actual multifracture propagation. The DA process developed in this study helps evaluate the diversion performance of particulate diverting agents. Furthermore, the machine learning model clarified the ambiguous performance evaluation of DA and enabled the prediction of the DA filtrate performance from complicated physical and chemical processes.
Compressed Air Pneumatics for Methane Mitigation
Authors: Garaway Isaac , Pang Kevin
Published: September 2022

Objectives/Scope

With the challenge of reaching carbon neutrality, the energy industry will need to be transformed. One of the key challenges facing the industry is eliminating Scope 1 emissions from the pneumatic devices used in wellpad automation and control. This practice accounts for roughly 45 million tons of CO2E/yr in the United States alone. Eliminating these emissions from existing brown-field sites is a significant challenge given that many of these well pads are in remote locations and suffer from a lack of reliable and sustainable electric power.

Methods, Procedures, Process

Compressed Air Pneumatics (CAP) is an innovative technology that replaces the methane emissions of pneumatic devices with clean, dry, compressed air. By employing highly reliable free-piston Stirling engine technology the end-user utilizes a small fraction of the normally vented methane to efficiently generate continuous and reliable electric power and clean, dry, compressed instrument air. CAP systems conserve valuable instrument gas and entirely eliminate methane venting at the well pad. They also eliminate the "wet-gas" issues associated with low-bleed pneumatic device contamination. In addition to compressed air for well pad automation, CAP technology is able to further provide additional utility grade electric power for additional well pad loads. Operators are able to further reduce their carbon footprint by harnessing the reject heat of the Stirling engine to keep process lines warm, further displacing the emissions of low-efficiency gas fired heaters. Another advantage that Stirling engine based CAP solutions gives upstream producers is the option to commission their instrument air system on tanked fuels like propane and readily switch over to instrument gas once wells are operational.

Results, Observations, Conclusions

A deployed CAP system on a multi-well pad in the Barnett Shale formation in Texas mitigated the vented emissions of 42,000 SCF of Methane in a 30-day period, which is equivalent to the removal of over 1,000 tCO2E on an annual basis, equivalent to removing 200 cars of the road. This same wellpad had zero downtime due to lack of pneumatic control or vent contamination across the same period. In addition to pneumatic control the CAP technology provided the wellpad prime power electricity, eliminating the need for large solar panels and cycling battery banks.

Novel/Additive Information

This technology when rightsized can maximize system value, driving down the cost of methane abatement below $2/tCO2e
Streamline Based Polymerflood Injection Optimization: Experiences in the Mangala Field, India
Authors: Li Ao , Chen Hongquan , Datta-gupta Akhil , Chitale Ashish , Shekher Sunit , Shankar Vivek , Kumar M Suresh , Ahmed Abaan , Das Joyjit , Kumar Ritesh
Published: September 2022

Mangala field (India) is one of the largest polymer flooding fields in the world with hundreds of wells and waxy crude oil. Field-scale optimization of polymer injection is challenging due to the geologic heterogeneity and operational constraints. This paper demonstrates an application of streamline-based injection optimization for the Mangala field. The paper will cover the mathematical foundation, optimization studies, and considerations for field implementation.

Our field application consists of five key stages: i) Problem framing. This includes defining optimization objectives, tuning parameters and constraints such as optimization start/end times, schedule update intervals, field rate targets, and injection/production limits for each well. ii) Rate optimization by streamline method. The optimizer iteratively reallocates the well rates, diverting the injected fluid to high efficiency injector-producer pairs located in upswept oil regions. iii) Optimal schedule interpretation. The rate change, flow pattern alteration and injection efficiency improvement are systematically examined, providing decision makers physical explanations of the suggested rate changes. iv) Selection of key injectors for field implementation. To avoid the risk of large-scale field implementation, limited number of injectors contributing the most to the oil production increase or water production decrease are selected for initial deployment. v) Potential field implementation and validation of the proposed plan based on field observations. Data from offset producers surrounding the rate-reallocated injectors can help evaluate oil production improvement or alleviated decline.

The optimized rate schedule is first compared with the current schedule in the field, honoring the field total liquid injection/production rates. The optimized case redistributes the rate allocation among high efficiency injectors within predefined bottom hole pressure and rate constraints. The cumulative oil production increase for the short-term optimization period, 11 months, is 0.66 MMbbl. The efficiency plots show efficient utilization of injected fluid after optimization and the bubble plots and streamline maps indicate that the optimizer alters the flow pattern for a better sweep of the remaining oil. Based on the full field optimization, 20 key injectors are selected for field implementation. Numerical simulation shows that 75% of total oil gain can be achieved from optimization of the key injectors. For field validation, offset producers are expected to show an arrest in the oil decline rate due to improved pressure support and, also reduced water cut increase after field implementation.
Laboratory Study and Field Application of High Temperature Resistant and Permeable Flooding Nanofluid for Enhanced Spontaneous Imbibition Oil Recovery
Authors: Xiao Lixiao , Hou Jirui , Qu Ming , Wang Weiju , Wen Yuchen , Liang Tuo , Wu Weipeng , Qi Pengpeng
Published: September 2022

Microemulsion with excellent properties has shown significant potential in enhancing oil recovery from tight formations by spontaneous imbibition. High temperature resistant and permeable flooding nanofluid (HTPF-NF) was prepared through microemulsion dilution method. Firstly, an evaluation process of HTPF-NF properties was evaluated through the particle size and high temperature resistant experiments, interfacial tension (IFT) and wettability measurements, as well as the static adsorption experiment. Meanwhile, Transmission Electron Microscope (TEM) was utilized to characterize the particle size and morphology of HTPF-NF before and after solubilization of the crude oil. Optical Microscope (OM) was also used to observe the morphological characteristics of emulsified oil droplets. Then, the spontaneous imbibition oil recovery (SIOR) mechanisms of- HTPF-NF were proposed ulteriorly by adopting imbibition tests and CT scanning technology. Moreover, the field application effects of HTPF-NF micro-fracture huff and puff in Shengli Oilfield were also analyzed. The results show that the optimum concentration of HTPF-NF is 0.2wt% with excellent comprehensive performances. Under this concentration, the particle size is 7.5 nm, the IFT value reaches ultra-low IFT, the wettability alteration ability is remarkable and the adsorption loss is minimized. Afterwards, adhesion work reduction factor (AWRF), solubilization coefficient (SC) and the self-driving force (SDF) are defined and calculated based on the IFT and contact angle for quantitatively analyzing the SIOR mechanisms. Furthermore, the data and images of spontaneous imbibition and CT scanning present that the longer the imbibition distance, the higher SIOR of HTPF-NF. In conclusion, the SIOR mechanisms of HTPF-NF are summarized as follows: remarkable property of solubilizing crude oil, brilliant ability of reducing oil/solid adhesion work by synergistic effect of IFT reduction and wettability alteration, and excellent capability of increasing imbibition distance by larger self-driving force. After soaking for two months, YB well was produced with the dramatic increase of the liquid production from 9.55 bbl/d to 34.5 bbl/d, the oil production from 5.15 bbl/d to 19.1 bbl/d and the water cut from 27.3% to 40.8%.
Onshore and Offshore EOR Applications in Brazil: A Review Study
Authors: Michelett Gustavo , Roberts Autumn , Kalyondo John , Habashi Aiden , Alhafidh Hasan , Hascakir Berna
Published: September 2022

This study reviews the existing oil and gas fields in Brazil located both onshore and offshore. Focus is on geology and production history of Santos, Campos, Reconcavo, Sergipe, and Potiguar Basins. We mainly reviewed the geological and reservoir characteristics of these basins, their production history, applied enhanced oil recovery (EOR) methods, and we finally made some EOR recommendations which may help to increase hydrocarbon recoveries in each basin.

At the beginning of the current decade, Brazil was producing almost 2 MM barrels of oil per day. Nowadays, the pre-salt fields alone (that started operating 15 years ago) produce an average of 1.67 MM bbl/d with a 2.73 MM bbl/d total daily oil production. In other words, the oil production from the basins other than the pre-salt fields started to decline of more than 50% in their production levels.

The divestment of many assets, located both onshore and offshore, opens a window of opportunity and a need for the new owners to apply EOR methods to bring back production to higher levels and recover their investments. By reviewing the data from three onshore fields from Reconcavo, Sergipe, and Potiguar and two offshore fields from the Campos basin, this paper has discussed issues and assessed alternatives that may similarly be applicable to other fields in the same basins. Buracica, Carmopolis, and Canto do Amaro fields presented almost none to low increase in production. One of the reasons may be credited to paraffin wax deposition. To avoid wax deposition and increase oil production, we proposed to combine two methods; a thermochemical method to avoid the buildup of wax with the addition of surfactant to the injected fluid to reduce the interfacial tension between water and oil and increase recovery. Both Jubarte and Marlim have achieved success with waterflooding but currently, a continuous decline is observed. Polymer flooding is proposed as a solution in these cases. The pre-salt fields are still ramping up production at very high rates. Hence, as an alternative, in those reservoirs, CO2-WAG might be applied in the near future before reaching a decline in the oil production.

This study briefly discusses the status of the oil and gas fields in Brazil both located onshore and offshore. Moreover, it provides quick recommendations for the existing problems in Brazil during oil and gas production via EOR methods.
Vaca Muerta Oil Production Facility Energy Efficiency Analysis
Authors: Correnti Augusto , Alzate Daniela , Arze Carolina , Gregorini Sofia , Frete Selene , Heins Andrea , Monzon Cesar , Asis Marcelo
Published: September 2022

Energy efficiency plays an essential role in accelerating clean energy transitions and achieving global climate and sustainable development goals. Global improvements in energy efficiency have been declining since 2015. Energy efficiency along with methane emissions and flaring reduction, is expected to deliver more than 40% of the reduction in energy-related greenhouse gas (GHG) emissions over the next 20 years in the IEA's Sustainable Development Scenario, which shows how to put the world on track to achieve international climate and energy goals in full.

The scope of the analysis focused on the Early Production Facility (EPF) operated by Shell Argentina in Sierras Blancas, which processes the oil and associated gas and water production of Vaca Muerta with an installed capacity of 12,000 bbl/d of crude. The period of analysis considered was from May 2020 to April 2021. Energy consumptions upstream of the processing facility, mainly from the producing wellpads, are out of scope. Within the EPF, the limit defined is the plant operations boundaries, and the scope includes the oil, water and gas processing facilities, lighting, flare, services, and plant office.

The analysis was developed in the frame of the Master on Sustainable Energy Development at ITBA and was based on the methodology required by the standard ISO 50.001 on Energy Management Systems for the energy review1.

The total energy consumption of the plant was measured and compared against the energy usage of the installed equipment. Fuel gas and diesel were identified as the primary energy sources of the plant; however, fuel gas represents more than 90% of the primary energy source of the facility and only 7 pieces of equipment represent more than 90% of the fuel gas consumption.

Both a fuel gas and an electricity balance were performed to validate the inputs of the analysis. Additionally, the energy uses were ranked. Improvement opportunities were identified for the operation and maintenance of the existing facilities, and for the design of future plants or revamps of the existing one. Potential savings of +10% in fuel consumption compared to the baseline were estimated based on previous experiences in analogue facilities2.

This analysis is replicable and scalable to all similar installations, so the methods and criteria used as well as main improvement opportunities identified are shared, with the aim of reducing Scope 1 GHG emissions at country level for upstream operations.
Lost Circulation Material Design for Engineered Fracture Gradient of Drilling
Authors: Nguyen Kien , Mehrabian Amin , Santra Ashok , Phan Dung , Bathija Arpita
Published: September 2022

Lost circulation material (LCM) is known to enhance the breakdown limit of wellbores. However, the related gain in the wellbore circulation density remains a weak link in the literature. A design scheme for the LCM blend is developed in this work that allows for quantification of the maximum enhancement in fracture gradient of wellbores. An analytical solution is developed for this purpose that accounts for wellbore inclination and azimuth. The LCM blend is selected by applying appropriate criteria for the particle size distribution (PSD) to the estimated width of near-wellbore fractures. A constitutive model for stress-strain behavior of the LCM is developed from in-house laboratory data of axial compression test on LCMs. The test is intended to simulate compression of the LCM plug upon partial closure of the fracture faces. The obtained constitutive model is used along with the presented analytical solution to estimate the fracture width, tip stress intensity and the wellbore stress redistribution after fluid filtrate leakoff and closure of fracture faces on the LCM agglomerate. The LCM blend composition is selected by optimizing the resulting variations in the fracture tip stress intensity and wellbore stress enhancement between the pre-leakoff (suspended particle) and post-leakoff (solid agglomerate) states of the deposited particles inside of the fracture. The compromise between fracture tip stress intensity factor and compressional stress redistribution around wellbore wall is shown to determine the extent of enhancement in the wellbore fracture gradient, i.e., the maximum circulation density that would not cause wellbore breakdown. Case studies with fracture gradient gains as large as one lbm/gal are presented.
The Impact of Gas-Oil Miscibility on Oil Recovery During Huff-and-Puff EOR in Organic-Rich Shales
Authors: Cruz Felipe , Mamoudou Sidi , Tinni Ali
Published: September 2022

Injection pressure is a key parameter in the design of a Huff-and-Puff EOR process in organic-rich shales. Reservoir engineering studies have shown that injection pressure and miscibility play a role during Huff-and-Puff EOR. However, during field implementation, the injection pressure is often limited by the number of compressors and in several cases, the gas injected might not reach sufficient pressure to achieve a state of complete miscibility with the oil. These scenarios lead to a condition of partial miscibility or immiscibility which impacts the efficiency of the recovery mechanisms during Huff-and-Puff EOR. The objective of this present study was to quantify experimentally the impact of complete, partial, and immiscible gas injection during Huff-and-Puff EOR in organic-rich shales.

For the purpose of this study, we have collected crude oil and wax preserved core samples from the Eagle Ford shale formation. The Eagle Ford shale samples were characterized by measurements of mineralogy, TOC, porosity, pore throat size, and specific surface area. We performed 20 Huff-and-Puff EOR tests in the shale samples at several different injection pressures, using two field gases and an immiscible helium gas. The minimum miscibility pressure (MMP) between the field gases and the crude oil was measured using the vanishing interfacial tension technique. Oil recovery for each Huff-and-Puff EOR cycle was quantified using NMR measurements. The produced hydrocarbon compositions were determined using a multi-step dry Pyrolysis measurement at the end of each Huff-and-Puff EOR test.

Our results show that injection pressure is one of the most important factors controlling the oil recovery during Huff-and-Puff EOR in shales using a field gas. We observe a strong linear increase in oil recovery as injection pressure increases. The injection of the field gas in either partially miscible or completely miscible conditions provides significantly larger oil recovery compared to the immiscible gas at the same absolute pressures. The oil recovery is three times larger for the field gas in a completely miscible condition compared to the immiscible gas and two times larger in a partially miscible condition. The multi-step dry Pyrolysis results show a preferential production of light hydrocarbon species regardless of the state of miscibility during Huff-and-Puff EOR.

The findings reported in this experimental study will help to optimize the design of field Huff-and-Puff EOR operations in organic-rich shales. The strong linear trend between the injection pressure and the oil recovery factor in the field gas tests can be used for the selection of gas compressors during field implementations. The superior performance of the field gas compared to the immiscible helium gas at the same injection pressures confirms the importance of miscibility during Huff-and-Puff EOR in organic-rich shales.
Experimental Study of Polymer-Alternating-Gas Flood
Authors: Pang Jieqiong , Mohanty Kishore
Published: September 2022

Carbon dioxide (CO2) flooding has a high microscopic displacement efficiency above the minimum miscibility pressure (MMP), but a low sweep efficiency due to gravity segregation and bypassing. In many fields, water-alternating-gas (WAG) is used to improve sweep efficiency, but early breakthrough and low sweep efficiency are common. The objective of this research is to evaluate the performance of polymer-alternating-gas (PAG) floods experimentally in the lab-scale. Continuous gas (CG), WAG and PAG flood experiments were performed in homogeneous and heterogeneous cores. Experiments conducted in homogeneous Berea cores showed that tertiary CG flooding and tertiary WAG flooding had similar incremental oil recovery and the tertiary PAG flooding had a lower incremental oil recovery. Heterogeneous core flood experiments showed that WAG flooding and PAG flooding had similar incremental oil recovery, which were slightly higher than that in the CG flooding. In linear cores, the gravity segregation effect is limited due to the small diameter of cores; so, the extent of bypassing is small. In heterogeneous cores, there is bypassing in CG floods due to permeability contrast and WAG / PAG floods help improve oil recovery. However, PAG oil recovery was no better than WAG oil recovery in these laboratory-scale core floods.
Maximize Reservoir Recovery in a High-Pressure Gas Field Through Re-Evaluating Integrity Of Production Tubulars and Liner Hanger Failure-Based Analysis
Authors: Mohy Amr , Miller Rich A. , El Kholy Sherif , Betancourt Mauricio , Mousa Mohamed
Published: September 2022

A high-pressure gas field in Egypt includes eight development wells drilled and completed: three wells in the West and five wells in the East. The reservoir management team had considered increasing the reservoir recovery by lowering the reservoir abandonment pressure below the initial design value. The eight wells in the field had slightly different production casing ratings and different liner hanger suppliers with different ratings and mechanisms. The impact of lowering the reservoir abandonment pressure had to be checked against all the eight wells in the field in terms of design assumptions and casing/equipment ratings. The main challenge was to lower the reservoir abandonment pressure while maintaining the wells integrity and reliability.

The production packer splits the production pipes into two pressure regimes: above and below the packer. The production pipe section and liner hanger above the production packer will be exposed to the reservoir abandonment pressure in case of communication below and above the packer (e.g., a packer leak near depletion). During the planning phase, the main limiting factor for the reservoir abandonment pressure was the liner hanger in most of the wells. When re-evaluating the potential for a lower abandonment pressure, multiple well barrier elements were considered in their as-installed condition, including pipe collapse, hanger hold-down capacity, and liner top packer differential pressure.

The conclusion of these assessments showed that the weak point was still the liner hanger system in most of the wells, so a further failure-based analysis was conducted on the liner hangers. The results defined an updated reservoir abandonment pressure that maintains well integrity.

This paper outlines the thorough well barrier elements design check and methodology used to support the decision to lower reservoir abandonment pressures and maximize reservoir recovery for the field.
Modeling and Analysis of Hydraulic Fracture Skin and Its Control on Shale Gas Production from Horizontal Wells
Authors: Atama Grace , Akkutlu Ibrahim
Published: September 2022

It is widely recognized that hydraulic fracturing creates a region of altered permeability near the fracture/matrix interface. Although we have a limited understanding, it is believed this region plays an important role on the production rates. The objective of this study is to model the region as a fracture skin explicitly including local physical and chemical phenomena and their associated effects, namely: (1) permeability improvement due to unpropped fracture development during the fracturing, (2) stress increase due to slick water invasion and clay-swelling effect developing after the fracturing, and (3) water-saturation buildup due to capillary end effect (CEE) developing during the flowback and production. A sensitivity analysis on the derived skin indicates key parameters controlling production and help in minimizing the damage.

The proposed fracture skin increases at a decreasing rate with distance away from the fracture/matrix interface, which mirrors the invaded fracturing fluid (slick-water) near the interface. The sensitivity analysis performed shows that clay swelling is the predominant damage mechanism and is controlled by the geo-mechanical parameters of the permeability model: (i) the normalized effective stress at the fracture matrix/interface when clay swelling develops in the altered zone, and (ii) strength of the unpropped fractures and cracks inside the damage zone to stay open. On the other hand, the contribution of CEE to the skin is mainly controlled by the average water saturation in the damaged zone. CEE can thus be severe in formations with high water saturation. To minimize the damage, the salinity of the injected water needs to be increased, which in turn will reduce the chemical imbalance between the clay-bound water and slick-water, preventing osmosis. In addition, using proppants with a wider particle size distribution could reduce the damage by allowing smaller size proppants to invade into secondary fractures and cracks, hence, keeping them propped open during the production.
Drillpipe Conveyed Cased Hole Logging: New Technology and Mode of Conveyance for Cement and Casing Inspection
Authors: Hawthorn Andy , Steinsiek Roger , Rahman Shaela
Published: September 2022

Casing and cement are probably the two most critical components for good well integrity through the life of a well. Understnding the condition and annular coverage of both is essential for many subsequent operations and may also, in many locations, be a regulatory requirement. Therefore, a good knowledge is needed of the internal dimensions of the casing, the ovality, the thickness of the casing, the level of corrosion or wear, and the material in the annular space behind the casing. As the industry moves towards a significant amount of mature fields there is a push towards accessing new reservoir exposure from within existing production infrastructure. This is leading to a significant increase in the number of re-entered wells, often in highly deviated wellbores. Sidetracking off an existing cased well requires a good understanding of the condition of the casing and cement. It is now often the case that casing and cement evaluation operations are required several times on the same well. Historically these measurements have only been available on wireline. What we shall describe in this paper is the development and early field results of a pipe conveyed equivalent. The best description of this is to consider it the analog of a logging while drilling tool, but specifically designed for cased hole interpretation and furthermore for casing inspection and cement mapping. The fact that we run drillpipe in the well on numerous occasions gives us the opportunity to acquire this critical data, often in parallel with existing operations, or acquiring it in real-time during the rig operation we are using the data for. We will demonstrate how this tool was designed, and some of the key differences between this and a wireline conveyed tool. These differences presented some specific challenges that needed to be overcome, not only in the mechanical design of the tool, but also in the way it handles and processes data downhole. We will then show, through case histories, some of the data sets acquired and their comparison with wireline for qualification of the tool. The field results will show the full range of measurements which this tool is capable.
Profiling Asphaltene Inhibitor Performance Using Asphaltene Dispersion, Particle Growth, and Onset Point Methods with Packed-Bed and Capillary Deposition Tests
Authors: Chiang Pinn-Tsong , Bian Yu
Published: September 2022

Asphaltene inhibitors (AIs) are commonly used to mitigate asphaltene deposition issues. AIs are believed to change asphaltene growth behaviors, including dispersion, aging, electrostatic interaction, and/or more parameters, and thus collectively impacting deposition rate. In this work, AI performance was profiled by different methods to identify the responsible mechanisms.

Particle growth profiles were first obtained based on traditional Turbiscan method (ASTM D7061) for larger particle dispersions. Subsequently, a modified Turbiscan method was used to assess the asphaltene growth kinetics. The indirect method was used to detect onset point. Packed-bed (5″ length; 0.334″ ID; 1.5 mm dia. bead) and capillary (100 ft length; 0.03″ ID) deposition tests were done at the same deposition flow rate (0.15 mL/min), time (20 h), and temperature (75 °C). Non-deposited residue was removed by cyclohexane at experiment flow rate. An extra fast flow rate (0.5 mL/sec) wash was applied on packed-bed setup to differentiate between loose and firm deposits.

Untreated sample, along with 150 ppm AI-1, and 150 ppm AI-2 samples were tested with a variety of methods. Overall, both AI-1 and AI-2 show great dispersion and delayed asphaltene particle growth compared to the untreated. The changes of asphaltene growth kinetics were reflected on packed-bed and capillary deposition results as deposition masses for AI-1 and AI-2 treated crudes decreased significantly compared to the blank. Capillary tests yielded less deposition compared to the packed-bed test counterparts. Some asphaltene particles are pushed out of the capillary before deposition due to the higher shear rate but deposited in when compared to packed-bed experiments. By adopting the fast flow rate wash on packed-bed column, we found high correlation between firm asphaltene deposit weight to capillary deposit weight.

By combining different test methods, AI effectiveness is determined at different kinetic stages. The performance profile can provide a systematic method to build structure-property relationships. We believe the testing protocol can facilitate new molecule development.
Wellbore Stabilizing Nanomaterial Assist to Drill Over-Pressured Formations
Authors: Addagalla Ajay , Moroni Luigi , Hoxha Besmir , Gad Ahmed
Published: September 2022

As the oil and gas industry looks for more prolific opportunities, the complexities of drilling have become more sophisticated and consequently there is more risk associated with borehole stability, differential sticking, and mud losses. Some wells, despite their very narrow operating window, require high mud weights to prevent borehole collapse. Therefore, wells are drilled with inherent risks of stuck-pipe, fluid losses, and possible set contingency casing string - all of which can be very expensive in terms of equipment, and lost time.

Drilling through shale is inevitable. Shale tends to be characterized as high in-situ stresses, fissile, laminated, with low permeability. It has been observed that wellbore stability problems occur due to lack of appropriate inhibition from drilling fluids. The most important variable in maintaining shale stability is the prevention of pressure invasion into the shale matrix. Shale stability is achieved when fluid invasion is reduced, and differential pressure support is maintained using pressure reducing additives that provide borehole support. There are many additives currently being used for this application, but all have their limitations, and not all are properly used for appropriate applications.

The latest development in Nanotechnology offers the opportunity to utilise the features of nano-sized particles (sub-micron) in drilling fluids where conventional products fail to deliver required wellbore stability at the target zones. The stabilizing nanoparticle is a dry solid with a particle size of approximately 100-200 nano-meters, deformable, stable, and with a dispersed zeta potential -10 to -20mV. The product can mechanically ‘seal’ micro-fractures and possibly large pore throats in shale thus assisting in forming a semi-permeable membrane. Additionally, the application of these particles could be extended to stabilize weak-bedding planes in geomechanically sensitive formations.

This paper will discuss a product that is suitable for use in both water base and oil base muds that functions to improve wellbore stability at high over-balance pressures. Herein, detailed laboratory work will demonstrate the product behaviour in different mud systems while reducing pore pressure transmission. Additionally, the product has shown to have great stability in high salt and high pH environments while being inert with respect to rheological property changes.
What Can Fluid Properties Do for You: Quantifying the Impact of Downhole Fluid Properties in Reservoir Petrophysical Characterization
Authors: Machado Patrick , Vasconcelos Adna , Bertolini Andre , Carneiro Giovanna , Dantas Marianna
Published: September 2022

Fluid composition has a direct impact on predicted petrophysical properties, mainly on those related to reserves estimation, such as total porosity, water saturation and volume of oil. However, most formation evaluation workflows use properties from literature or black oil models with built-in fluid properties, not considering the effects of different fluid compositions.

This study analyzes petrophysical answers of a target Brazilian carbonate presalt well using a well-established multiphysics inversion workflow with three different approaches for determining fluid properties. The source of the benchmark data used for the fluid properties is a wireline formation tester which can acquire ultra-clean samples from several depths and estimate fluid properties.

The scenarios for assessment of fluid properties are: (a) standard/usual values for presalt fields, (b) properties estimated from a black oil model, (c) and properties estimated from a properly calibrated thermodynamic package. The impact of fluid properties uncertainty is quantified using petrophysical properties estimated using PVT (pressure-volume-temperature) derived fluid properties as the benchmark.

The goal of this study is to quantify the impact of downhole fluid properties throughout petrophysical evaluation workflows and production estimate, mainly for complex fluid composition, such as high CO2 (carbon dioxide) content or light fluids.