bluuebunny/crossref_metadata_2025_split huggingface dataset:
Culture Eats Strategy for Breakfast: Developing Coaching Cultures in the Oil and Gas Sector
Authors: Hamp Roland , Webster David 
Published: September 2019

Abstract
Oil and gas businesses are often characterised as operating in volatile, uncertain, complex and ambiguous (‘VUCA’) environments, whilst also expected to meet ever more demanding operational challenges and stakeholder expectations. Within this setting the historically prevalent directive, ‘command and control’ leadership style has become increasingly ineffective at creating a workplace culture which fully enables and engages staff, especially millennials, to deliver outstanding results sustainably. This paper looks at what it takes for an organisation to shift towards a ‘coaching culture’, one in which exceptional performance is gained by a significantly higher quality of conversation between all involved in the business. The paper discusses the business context for a modern oil and gas business which necessitates a shift towards a ‘coaching culture’ for many in the sector; it sheds light on the critical elements of such a change programme and the key steps that are required for such a change to be successful; it examines the theoretical basis for development of a coaching leadership style in the sector; and it shares the authors’ practical learning from the field gained through implementation of such programmes in the sector, with examples and composite case studies.
Rigsite Thermal Treatment of Cuttings Enables Improved HSE Performance in 24-Well Campaign in the UK North Sea
Authors: Smith John , Eccles Graham 
Published: September 2019

Abstract
On offshore rigs, oil-based mud (OBM) cuttings can create logistical and environmental risks. Onshore disposal requires costly transport, and bad weather can halt shipping operations. The liability for waste treated onshore belongs to the operator. Although offshore disposal removes this liability, UK North Sea regulations specify that oil on cuttings (OOC) must be less than 1%. (by weight?) A rigsite thermomechanical cuttings cleaner (TCC) applies high temperatures to help reduce OOC to less than 1% and recovers base oil and water for reuse.
A TCC unit was installed on a semisubmersible rig to process OBM cuttings for a 24-well program. Mechanical action is applied directly to the cuttings by means of hammers that create friction, causing temperatures to exceed the boiling points of water and oil so that hydrocarbons are separated. The oil and water vapors are removed and condensed where the base oil and water are further separated and recovered. The TCC process on this rig was supported by vacuum-pump conveyance equipment and specialized storage tanks. Cuttings were no longer shipped to shore, and crane lifts associated with "skip-and-ship" operations were minimized significantly.
The TCC unit processed 14,500 metric tons (MT) of OBM cuttings throughout the duration of the 24- well program. The total footage drilled with OBM was more than 160,000 ft. All cuttings were disposed offshore. Approximately 13,500 bbl of base oil (valued at USD 135/bbl) was recovered for reuse in the drilling fluid system. The TCC unit ran for a total of 3,500 hours with zero downtime or nonproductive time (NPT) associated with cuttings disposal. The average is approximately 150 operating hours per well. One important benefit was the dramatic reduction of skips handling and crane lifts, which provided safer working conditions for rig crews. On a conventional skip-and-ship operation, the operator would fill and transport up to 35 skips per day. This translates to 2,380 crane lifts per well that were unnecessary. Offloading delays caused by bad weather were no longer a factor, thus helping reduce uncertainty and saving valuable rig time. Processing this volume of drill cuttings offshore meant that more than 57,000 skip crane lifts were avoided. The TCC mobilization process for this program was executed efficiently by coordinating with quayside contractors (welders, platers, electricians, etc.) to complete much of the installation work scope onshore.
Thermal treatment enables operators to address stringent offshore discharge regulations globally, excluding countries with zero discharge policies. Cost benefits include the following: No "wait on weather" time (rig day rate = USD 300,000)No dedicated vessels for transportNo quayside cuttings handlingNo trucking to treatment and disposal facilities
Safety and environmental benefits add the following value: Reduced manual handling of skipsReduced crane liftsBase oil reuseLiability for waste ends at rigsite
Multicomponent Diffusion Modeling of Cyclic Solvent Injection in Ultratight Reservoirs
Authors: Cronin Michael , Emami-Meybodi Hamid , Johns Russell 
Published: September 2019

Abstract
We present a new semi-analytical compositional model specifically designed for hydrocarbon recovery (primary and cyclic solvent injection processes) in ultratight oil reservoirs based on multicomponent diffusion-dominated transport within the matrix. The semi-analytical solution consists of a well-mixed tank model for the fractures coupled to diffusive transport within the matrix. Production of oil, gas, and water from the fractures is proportional to its phase mobility. The matrix allows for differing effective diffusion coefficients for each component. Because there are no grid blocks within the matrix the analytical solution is computationally less expensive than numerical simulation while capturing the steep, non-monotonic compositional changes occurring a short distance into the matrix owing to multiple injection cycles. The Peng-Robinson equation-of-state is used to calculate phase behavior within the analytical framework.
The solution is validated with several lab and field-scale cases. For primary recovery, the results show that the diffusion-based model correctly reproduces the pressure and oil recovery declines observed in the field. We show that the hydrocarbon recovery mechanism for solvent huff’n’puff (HnP) is facilitated by greater density reduction and compositional changes (increased compositional gradients). Two solvents are considered in HnP calculations; carbon dioxide (CO2) and methane (CH4). Recovery of heavier components is enhanced with CO2 compared to CH4, but methane has overall greater oil recovery than carbon dioxide for the cases considered. Furthermore, the results demonstrate that multiple HnP cycles constrained to surface injection are needed to enhance density and compositional gradients, and therefore oil recovery. While shorter soaks are better for short-term recovery (i.e. 3 to 5 years), longer soak periods maximize recovery over a longer timeframe (i.e. 10 to 15 years). This paper provides a novel way to model the optimum number of cycles and duration and when to start the HnP process after primary recovery for the limiting case of diffusion only transport where matrix permeabilities are very small (k &lt; 200 nD).
Time-Enhanced Material Balance Analysis
Authors: McNeil Ralph G , Antonov Aleksandr , Tabatabaie S. Hamed , Mattar Louis 
Published: September 2019

Abstract
The traditional Material Balance Analysis only utilizes cumulative production and static average reservoir pressure. Time does not feature in the equations. However, there are significant advantages if time is incorporated into the analysis. For example: a) identifying if all the wells belong to the same reservoir; b) identifying the effect of external energy sources such as gas or water drive; c) incorporating the contribution of communicating tight reservoirs; d) visualization of the results in pressure-time format.
The time-based analysis presented in this paper supplements the conventional methods. It helps reduce the non-uniqueness of the solution. In contrast to the conventional Havlena-Odeh plotting variables, which are complex and non-intuitive, the pressure-time plot and corresponding pressure-history match are much easier for an engineer to comprehend and to evaluate the validity or uniqueness of the results.
Optimization of Multi-Fractured Horizontal Well Completion: A Montney Example
Authors: Haghshenas Behjat , Qanbari Farhad 
Published: September 2019

Abstract
After a successful decade of exploration and development activities in major tight/shale reservoirs, the industy now has access to incredible sets of data, modeling tools, and technologies for multi-fractured horizontal well (MFHW) completion. A review of the available data and models shows that performance of a MFHW is governed by hydraulic facture properties (dimension, conductivity, and distribution) and reservoir fluid and rock characteristics (reservoir fluid properties, and rock storage and flow capacities). Workflows are required to link the characterization attempts (reservoir and MFHW), learnings from completion expriments, modeling approaches (reservoir and fracture modeing) and pettern recognition exercises (relationship between well performance metrics and the governing parameters).
In the current study, an interative workflow is proposed for design and optimization of MFHW completion based on a mixed-method approach combining three major paradigms: experiments, modeling, and data science. Each cycle of the workflow starts with data gathering and characterization of reservoir fluid and rock, followed by reservoir and fracture modeling, statistical analysis, updated design, economc analysis, and ends with implementation, monitoting and data analysis. The first cycle of the workflow is the most time-consuming and tedious one which requires a great deal of discussions and instructions.
The proposed workflow is tried on a population of Montney gas condensate wells. Rate-transient analysis (RTA) and numerical reservoir modeling were applied to a group of 16 Monteny gas condensate wells with detailed daily production and flowing pressure data. Further, a simplified RTA-based approach and statistical analysis were applied to more than 90 Montney gas condensate wells (from the same region) with publically available production data.
A new design with optimized completion paramteres is obtained from the results of RTA, numerical reservoir modeling, statistical and ecnomic analyses. The new design is applied to six new wells in the same area. The average performance of the new wells is reasonably close to the predicted performance by the proposed workflow. The workflow is believed to optimize the well performance, save the operator millions of dollars through optimization, and give the management and technical teams confidence in the next phase of corporate planning.
Comparison of the Methods for Analyzing Rate and Pressure Transient Data from Multistage Hydraulically Fractured Unconventional Gas Reservoirs
Authors: Atadeger Aykut , Batur Ela , Onur Mustafa , Thompson Leslie G. 
Published: September 2019

Abstract
In this study, we provide a detailed review and comparison of the various graphical methods, available in the literature, to interpret/analyze rate and pressure transient data acquired from multistage hydraulically fractured horizontal wells (MHFHWs) completed in unconventional gas reservoirs. The methods reviewed are based on transient matrix linear flow (Ibrahim and Wattenbarger 2006; Nobakht and Clarkson 2012a, 2012b; Chen and Raghavan 2013) and boundary-dominated flow due to the stimulated reservoir volume (SRV). The methods for boundary-dominated flow are the contacted volume methods based on the ending times of linear flow (Wattenbarger et al. 1998; Behmanesh et al. 2015) and the material balance methods (FBMs); Agarwal-Gardner method (Agarwal et al. 1999) and conventional method involving plotting rate-normalized pseudo pressure versus pseudo time material-balance time. We delineate the advantages and limitations associated with each method and identify the best methods of interpretation and analysis. Three different production modes; constant rate (CR), constant bottomhole-pressure (CBHP), and variable-rate/bottomhole pressure, are considered. For comparison, various synthetic test data sets generated from a high-resolution spectral gas simulator, which treats nonlinear gas flow rigorously and accurately to simulate rate transient data, is used. Both synthetic noise-free and noisy rate/pressure data sets considering wide ranges of initial reservoir pressure and bottomhole pressure as well as real field data sets are used to compare the methods. For linear flow, the Nobakht-Clarkson method yields the best results, although its use is tedious as it requires an iterative procedure. The Chen-Raghavan method for linear flow seems to provide comparable results to the Nobakht-Clarkson method, but does not require iterative procedure. The Ibrahim-Wattenbarger method for linear flow analysis always overestimates flow capacity as compared to the other methods. For boundary dominated flow, the results show that the Agarwal-Gardner FBM method is quite vulnerable to the error in rate/pressure data, while the conventional FBM method is more robust to noise and provides more accurate estimates of gas in place. Among the methods based on the ending time of linear flow, it was found that unit-impulse method based on Behmanesh et al. (2015) provides best results for predicting gas in place.
A Robot for Removing Hydrate and Paraffin Plugs in Offshore Flexible Lines – Development and Experimental Trials
Authors: Santos Hugo , Perondi Eduardo , Wentz André , Silva Anselmo , Barone Dante , Basso Eduardo , Reis Ney , Galassi Maurício , Pinto Hardy , Castro Bruno , Ferreira André , Ferreira Lincoln , Krettli Igor 
Published: September 2019

Abstract
Methane Hydrates and Paraffin Plugs in flexible lines are concerns in offshore production. They may stop wells for months, causing high financial losses. Sometimes, operators use depressurization techniques for hydrate removal. Other strategy is using coiled tubing or a similar unit in order to perform local heating or solvent injection. However, frequently these strategies are not successful. In those cases, a rig may perform the operation or the line may be lost.
This project developed a robotic system in order to perform a controlled local heating and remove obstructions. The robotic system developed is able to access the line from the production platform. It uses a self-locking system in order to exert high traction forces. An umbilical with neutral buoyancy and low friction coefficient allows significant drag reduction. It allows moving upwards and in pipes with a large number of curves. Coiled tubing and similar units cannot do that. Carbon fiber vessels and compact circuits give flexibility to move inside 4-inch flexible pipes. A novel theoretical model allows the cable traction calculation using an evolution of the Euler-Eytelwein equation.
Experimental tests validated this model using curved pipes, both empty and filled with a fluid and using different loads. Experimental tests also validated the external layer traction resistance. Furthermore, the carbon fiber vessels were pressure tested, indicating a collapse resistance of more than 550 bar (8.000 psi). In addition, exhaustive tests of the onboard electronics and of the surface control system guarantee the communication reliability.
Additionally, the 25 kN (5.6 kip) traction system was modeled theoretically considering the self-locking system, the contact with the wall and a diameter range. Four prototypes allowed to: a) compare hydraulic and electric drive systems, b) validate the self-locking mechanism up to its limit, c) analyze the hydraulic system for leg opening and translation and d) prove the traction capacity. Finally, a theoretical model for the local heating system was developed. The system experimental validation on a cooled environment demonstrated its capacity of increasing temperature. Furthermore, it allows the obstruction removal in a controlled manner, avoiding damage to the polymeric layer of the flexible line.
Application of Inter-Fracture Injection and Production in a Cluster Well to Enhance Oil Recovery
Authors: He Youwei , Cheng Shiqing , Chai Zhi , Patil Shirish , Rui Ray , Yu Haiyang 
Published: September 2019

Abstract
Applications of cluster wells and hydraulic fracturing enable commercial productivity from unconventional reservoirs. However, well productivity decrease rapidly for this type of reservoirs, and in many cases, it is difficult to maintain a productivity that is economical. Enhanced oil recovery (EOR) is therefore needed to improve well performance. Traditional fluid injection from other wells are not feasible due to the ultra-low permeability, and fluid Huff-n-Puff also fails to meet the expected recovery. This work investigates the feasibility of the inter-fracture injection and production (IFIP) approach to increase oil production of multiple multi-fractured horizontal wells (MFHW).
Three MFHWs are considered in a cluster well. Each MFHW includes injection fractures (IFs) and recovery fractures (RFs). The fractures with even and odd indexes are assigned to be IFs or RFs, respectively. The injection/production schedule falls into two categories: synchronous inter-fracture injection and production (s-IFIP) and asynchronous inter-fracture injection and production (a-IFIP). To analyze the well performance of multiple MFHWs using the IFIP method, this work performs numerical simulation based on the compartmental embedded discrete fracture model (cEDFM) and compares the production performance of three MFHWs using four different producing methods (i.e., primary depletion, CO2 Huff-n-Puff, s-IFIP, and a-IFIP). Although the number of producing fractures is reduced by about 50% for s-IFIP and a-IFIP, they achieve much higher oil rates than primary depletion and CO2 Huff-n-Puff. Sensitivity analysis is performed to investigate the impact of parameters on the IFIP. The fracture spacing between IFs and RFs, CO2 injection rates, and connectivity of fracture networks affect the oil production significantly, followed by length of RFs, well spacing among MFHWs and length of IFs. The suggested well completion scheme is presented for the a-IFIP and s-IFIP methods. This work demonstrates the ability of the IFIP method in enhancing oil production of multiple MFHWs in unconventional reservoirs.
Numerical Investigation to Understand the Mechanisms of CO2 EOR in Unconventional Liquid Reservoirs
Authors: Zhang Fan , Adel Imad A. , Saputra I. W. , Chen Weidong , Schechter David S. 
Published: September 2019

Abstract
Observations from pilot wells along with laboratory experiments have revealed the significant potential of CO2 as an EOR agent in unconventional liquid reservoirs (ULR). This study focuses on unveiling the mechanisms of gas injection EOR through a combination of experimental results, ternary diagram analysis, and core-scale simulation. In addition, laboratory results were upscaled to the field-scale to evaluate the effectiveness of the CO2 injection in production enhancement from ULR.
Gas injection experiments were performed at different pressures, and the laboratory results were upscaled to evaluate the production enhancement through gas injection EOR in ULR. A CT-generated core-scale model was utilized to investigate the mechanisms of gas injection EOR. Mechanisms such as diffusion and multi-contact miscibility were determined from core-scale simulation through history-matching experimental results, then upscaled to the field-scale model. Ternary diagrams reveal that EOR by gas injection is only effective at pressures greater than the Minimum Miscibility Pressure (MMP). Alteration of the injected gas and composition of crude oil clearly has an implication on changing the ternary diagram.
The primary production mechanisms of CO2 EOR are multi-contact miscibility, vaporizing/condensing gas drive, oil swelling, and diffusion. Gas injection experiments recovered up to 45% of the Original Oil In Place (OOIP) at 3,500 psi, but the recovery factor was less than 5% when operating below the MMP. Diffusion has a minor effect in enhancing oil recovery in ULR based on the core-scale history-matching results. The multi-contact miscibility is found to be the primary driving mechanism for oil extraction during gas injection. Ternary diagrams analysis clearly demonstrates that MMP plays a significant role in gas injection and that miscible conditions need to be achieved for EOR projects in ULR. CT-scan technology is utilized to demonstrate the movement of the fluids inside the cores throughout the experiments. Thus, we can determine the high flow path regions of the core plugs. Additionally, the impact of injection pressure and the start time of the gas injection process were analyzed using the field-scale model. The simulation results indicate that gas injection has significant potential of enhancing oil production in ULR. This study not only reveals the mechanisms of gas injection in ULR, but also provides a method for designing and optimizing gas injection for Huff-n-Puff EOR.
This study challenges the paradigm that diffusion is the dominating parameter of CO2 injection EOR in ULR. The novelty comes from the establishment of gas injection EOR mechanism in ULR through a thorough analysis of laboratory experiments, core-scale simulation, and ternary diagram analysis. In addition, a new modeling workflow for the design of gas injection strategies is proposed to unveil the real potential of gas injection.
Case Study: Human Factors Analysis of FPSO Operations Activities in Brazil
Authors: Franca Josue , Luquetti dos Santos Isaac , Haddad Assed 
Published: September 2019

Abstract
Production and drilling activities in offshore installation are one of the most necessary activities of human society. To drill a subsea well and raise the crude oil to a platform, by itself, presents a series of risks. Associated with this activity, when the crude oil reaches the topside of the platform, there are a number of operations that prepare the oil and gas to be exported to land by pipelines or oil tanker vessels, which involves equipment and process that take high temperatures, high pressure and high flow rates. Understanding the dynamics of the factors that can affect the interaction of operators with all these offshore complex systems is critical, because the loss of control of these systems can cause serious accidents, resulting in injuries to workers, environmental damage, loss of production and geopolitical crises. Accidents in the oil and gas offshore installations, such as drilling rigs and FPSOs, can have tragic consequences and all efforts should be targeted to prevent its recurrence. Therefore, from the perspective of current technological developments, it is essential to consider the influence of Human Factors in the risk management of offshore industrial plants.
Career Development Essentials for Young E&P Technical Professionals
Authors: Lau Hon Chung 
Published: September 2019

Abstract
This paper discusses career development essentials for young E&P technical professionals to realize and use for career planning. By dividing the professional life of the E&P professional into the early-career, mid-career and late-career stages, each spanning about twelve years, the author discusses career development essentials and their benefits in each stage. In the early-career stage, essentials include understanding the corporate culture, developing technical depth and breadth and developing good interpersonal team skills. In the mid-career stage, essentials include developing leadership skills, moving out of one's comfort zone, mastering cross discipline competency and developing a strong professional network. In the late-career stage, essential include anticipating future trends, leveraging one's strength and experience, developing others and leaving a legacy.