bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Multifaceted Strategy to Achieve Significant Reservoir Simulation Work Flow Efficiency Gains
Authors: Kaczorowski Norman , Knyazev Alexander , Ghassan Majed , Brock Nigel , Wilby Geoff , Engle Colin , Bogachev Kirill 
Published: November 2017

Abstract
A multifaceted strategy is presented which achieved significant reservoir simulation work flow efficiency gains at an operating company. The components of the strategy, including hardware and software, are detailed, and the relative efficiency gain is quantified with respect to the previous approach. The relative business value achieved by implementing the strategy is discussed. The new strategy improved efficiency by leveraging modern technology to impact those tasks of routine reservoir simulation work flows not directly related to reservoir engineering. This involved changes in three primary areas of the classic simulation routine of pre-processing, processing, and post-processing. A turn-key high-performance computing (HPC) solution for hosting data storage and executing simulation job processing was designed and implemented. A modern state-of-the-art simulator was configured for simulation job processing. An innovative simulation project management technology solution was deployed to organise and drive the reservoir simulation work flows and associated data management. The in-place HPC solution was constrained by the configuration of the compute nodes, lack of a master node, and the storage solution. These were configured inefficiently to the point that the expected gains from fast processing capacity were not realised due to other choke points in the compute processing and network. To realise the full potential of fast processing in a modern parallel environment, a custom HPC solution was designed. The custom solution allowed for better communication between the compute nodes and the storage, and incorporated an integrated master node. Next, simulation jobs were configured to run on a modern state-of-the-art simulator optimised for advanced HPC hardware. The new simulator significantly reduced model run times. Lastly, an innovative simulation project management technology was deployed on the reservoir engineer workstations. This technology allowed the engineers to reduce the time spent managing data, and to increase the time spent engineering. The preand post-processing engineering tasks were also made more efficient with the technology. The net result of the new strategy was to increase simulation throughput eight times. The higher volume of throughput led to more optimised engineering solutions and eventually allowed for the development of more complex simulation models. The multifaceted strategy to improve reservoir simulation work flow efficiency combines optimisation of the hardware and selecting software technologies conducive to modern HPC environments to allow engineers to focus the majority of their efforts on engineering rather than on systems and data management.
Finite Element Based Optimization and Improvement of the Sucker Rod Pumping System
Authors: Langbauer C. , Antretter T. 
Published: November 2017

Abstract
Low oil prices push the demand for efficient production, especially in mature fields. The reduction of artificial lifting costs by increasing efficiency is essential for extending the meantime between failure, the economic limit of the reservoir and the increase of the recovery factor.
For achieving these goals, the Finite Elements Method (FEM) is used for modelling and analysing the behaviour of the sucker rod string. Based on the results an optimisation of the whole pumping system is performed, which does not only consider subsurface equipment, but in addition also the surface facilities. The main target is to carry out a diagnostic analysis to evaluate the performance of existing units as well as a predictive analysis to optimize their performance and to design new units.
This paper summarizes the concept and the capabilities of the employed sucker rod pumping system analysis, based on the results of the sucker rod string FEM – simulation, including downhole pump as well as surface unit improvements. The model and the simulation results are verified by a comparison with downhole dynamometer measurements, obtained by several self-developed DDS (Downhole Dynamometer Sensor) during field tests. The presented simulation concept yields more accurate results than currently available commercial software products and in addition allows maximum flexibility in terms of sucker rod string composition, operation conditions, fluid conditions and the choice of installed equipment.
A comparison conducted on the performance and efficiency of a standard pumping system design and an optimized pumping system design resulted in an increased energy efficiency of more than 30%.
Formation of Mercaptans and Organosulfur Species in Claus Process
Authors: Rahman Ramees K. , Raj Abhijeet G. , Ibrahim Salisu 
Published: November 2017

Abstract
The formation of mercaptans and organosulfur species in Claus process leads to a reduction in the sulfur recovery efficiency, and an increase in the cost of tail gas treatment. While process optimization can be used to minimize their production in plants, the existing models fail to predict their concentrations to a reasonable accuracy. This study provides a detailed and validated model for Claus process including organosulfur species reactions that can be used in process optimization. A Claus mechanism, developed in a previous study, was used as the base mechanism. To this, the organosulfur reaction mechanism, developed using quantum chemistry, was added. The rate constants of the elementary reactions were determined using transition state theory. New rate parameters were validated with experimental data from the literature as well as from the sulfur recovery units in the UAE. The reaction furnace of the Claus process was modelled as an adiabatic plug flow reactor, and the waste heat boiler was modelled as a heat exchanger. New reactions and their rates for COS and CS2 formation provided a good match between the experimental data and the computed values. The important reactions contributing to COS formation were: i) CO+S3=COS+S2; ii) COS+O=CO2+S; iii) COS+SH=CO+HSS. Similar analyses were done for other organosulfur species to find the reactions responsible for their formation. The process simulations of SRU thermal unit were conducted using Chemkin Pro software to determine the conditions under which their concentrations can be minimized in the furnace. COS concentration was found to be reducing beyond 1500 K while mercaptans were destructed around 1050 K. It is also observed that CO concentration increased due to the thermal cracking of CO2. The presence of CO2 and fuel gas in the feed to the Claus process was found to be contributing highly to the formation of organosulfur species, but the furnace temperature played a vital role in their formation and destruction. The model developed in this study successfully predict the concentrations of organosulfur species including mercaptans, COS and CS2 in Claus process that will help in the optimization of process parameters to minimize their formation, maximize the sulfur recovery efficiency, and reduce the load on downstream catalytic units.
Application of Comprehensive Harmless Waste Treatment Technology to Treat Drilling Cuttings in the Tian Mountain Front Block in Tarim Basin
Authors: Jinzhi Zhu , Long Li , Da Yin , Jiaxue Li , Shaojun Zhang , Yuping Yang , Jie Zhang , Yushuang Liu 
Published: November 2017

Abstract
Due to high temperature, high pressure, and gypsum-salt formation, the stability and rheology of conventional polymer drilling fluids are difficult to maintain, so sulfonated drilling fluids (SDF) or oil-based mud (OBM) are recommended to drill deep formations or ultra-deep formations.
However, a large number of sulfonated drilling cuttings or oily cuttings are generated in the process of drilling operation. These drilling cuttings contain a large number of harmful substances, including petroleum hydrocarbon, sulfonated additives, heavy metals, and so on, which are toxic and difficult to be biodegradable, so the discharge of drilling cuttings into environment will lead to serious contamination of soil and groundwater.
Therefore, the environmental impact of the use of SDF or OBM is one of the main challenges facing petroleum industry. One of the most difficult environmental problems to resolve at the well site is the disposal of drilling cuttings, which is often physically unstable and unsuitable for landfill.
High temperature deep pyrolysis technology (HDPT) is developed to treat sulfonated drilling cuttings from deep formations. The field results indicate that the content of petroleum hydrocarbon of treated drilling cuttings is less than 16 ppm, and various indexes of treated cuttings could meet the requirement of environmental protection. HDPT technology is characterized by high treatment efficiency and no secondary pollution, and it is very suitable for harmless treatment of sulfonated drilling cuttings.
Leaching and resource utilization technology (LRET) is currently applied to treat oily drilling cuttings from ultradeep complex formations. The results indicate that the oil content of treated drilling cuttings is less than 0.6%, and the recovery rate of OBM is over 20%. LRET technology can not only recycle and reuse OBM resources, but also guard against environmental pollution from drilling operation, and thus produce great economic and environmental benefits.
Comprehensive harmless waste treatment station for drilling cuttings is built in this Block. HDPT and LRET technology can provide a powerful technical support for achieving safety drilling in this Block, and they have been successfully applied to treat drilling cuttings from dozens of wells in this Block. This paper presents field data to illustrate the application of this comprehensive harmless waste technology and evaluate the potential technical and economic benefits that it might provide to petroleum development and production in Tarim Basin.
Use of Data Analytics to Improve Well Placement Optimization Under Uncertainty
Authors: Busby Daniel , Pivot Frédérik , Tadjer Amine 
Published: November 2017

Abstract
Well placement optimization is probably one of the most challenging problems the oil & gas industry has to face particularly for green fields development. The complexity of the task comes from different factors: huge number of possible solutions, increasing size of reservoir models, difficulties to correctly modeling and handling uncertainty, complex well trajectories and operational constraints, … The optimization problem for multiple wells is also extremely hard to solve due to the exponential number of possibilities to test. Although several optimization methods have been proposed in scientific and technical articles, the most used approach in industry remains the manual optimization performed by well trained reservoir engineers. The workflow proposed here aims at assisting reservoir engineers to better perform their choices on main factors affecting the optimal well placement and to be able to test much more well configurations. To this end, a machine learning algorithm is trained on simulated data to be able to evaluate the performance of new possible well locations and configurations. Differently to previous experimental design approaches, complex geological features based on expert knowledge are extracted from the geological model in order to find the main factors driving the production mechanisms. Both properties along well trajectories and properties corresponding to connected reservoir zones are used as features in the machine learning method. Clustering techniques are used to select the training data to simulate used by the machine learning algorithm. The method also handle geological uncertainty that is a critical factor in well placement optimization particularly for green fields. A large number of realistic horizontal well trajectories honoring the different operational constraints is generated, then once the machine learning method is validated a very large number of these trajectories combinations can be evaluated in seconds.
The result of the approach are illustrated in a realistic synthetic green field where the objective is to optimize the position of three wells two producers and one injector under uncertainty (corresponding to several geological realizations). A test on real field case has also been performed, but will be presented in more details in a future work. Data analytics methods allow us to evaluate millions of possible well placement configurations on many geological realizations by performing only a few thousands full field reservoir simulations. We demonstrated this could help engineers placing wells in very profitable positions minimizing risk while maximizing long term production.
Supervised Waveform Analysis to Find Wasia Carbonate Stratigraphic Traps in Rub' Al-Khali Basin, Saudi Arabia
Authors: AlQattan Hussain , Zhang Sihai 
Published: November 2017

Abstract
The Wasia Formation presents opportunities to explore for stratigraphic traps in the Saudi Arabian Rub’ Al-Khali Basin because it contains numerous interbedded reservoirs, sources, and sealing rocks. The mid-Cretaceous Wasia Formation includes a rudist carbonate platform with five, third-order sequences comprising, from oldest to youngest, Safaniya, Mauddud, Ahmadi, Rumaila, and Mishrif members. These members include proximal shallow-marine, highstand carbonate shoals at the platform margin in close proximity to fine-grained carbonate deposits in the Shilaf Basin. The resulting depositional cycles and stratigraphic architecture position muddy-tight seals, adjacent to porous shallow-marine carbonate-shoal bodies. Two members (Safaniya and lowermost Mishrif) have high organic-matter content situated in the oil window.
Core data, well logs, seismic signals, and modern analogs were analyzed to help understand the Wasia deposition. Detailed correlations were made of well logs and neural network training was used to generate electro-facies. Next, supervised waveform analysis was used, correlated to five well log facies, to create five waveform facies including (1) lagoon, (2) back-shoal, (3) shoal, (4) slope, and, (5) basin facies. Sources of potential uncertainties include data processing, seismic to well ties, position of stratigraphic tops and seismic horizon interpretation. To minimize these, care was taken in data processing and a blind test was performed to validate the final interpretation.
On the basis of integrating the aforementioned data with our waveform facies, a reference geological model was built demonstrating that potential stratigraphic traps are porous, shallow-marine carbonate shoals intercalated with muddy-tight slope deposits resulting in isolated, porous carbonate reservoir bodies sealed by tight rocks. For example, the Ahmadi Memberseal was deemed to be too thin to seal the oil in the underlying Mauddud. In addition, muddy-tight lowermost Mishrif Member strata are also too thin to seal oil in the underlying Rumaila. In the worst case, laterally extensive upper Mishrif reservoirs are not sealed by interbedded lateral seals even though the Aruma shale seals their tops. The two best trap configurations include (1) the first highstand lower sequence of the Mishrif reservoir sealed by interbedded extensive transgressive muddy Mishrif carbonates and (2) thick Ahmadi and lowermost Mishrif fine-grained carbonates sealing Mauddud and Rumaila highstand system tracts.
Outlast the Blast, Avert the Loss
Authors: Ajith Shenoy Manur , Adel Khalid , Al Awadhi Ibrahim 
Published: November 2017

Abstract
Buildings that are manned and/or housing critical equipment are ideally conceived to be sited at safe distance away from potential explosion sources of the gas processing facilities. However it is not always possible to maintain the required stand-off distance due to several layout/operational constraints in brownfield projects and hence plant buildings are invariably subjected to the blast effects. The paper discusses challenges confronted and best practices followed in GASCO for blast protection of plant buildings.
Quantitative Risk Assessment study forms the basis for blast considerations on the building, wherein potential Vapor Cloud Explosion scenarios are identified and blast overpressure are quantified in the form of contours on the plot. Buildings located within the blast contours and are manned/housing critical equipments are classified as blast-resistant to ensure safety to occupants and facilitate safe shutdown of process units during explosion. Building performance requirement defining acceptable level of damage is determined based on criticality of the facility/expected occupancy (control room, FAR, etc.). Structural system/material appropriate to blast intensity is chosen and a dynamic or equivalent static analysis is performed.
Blast resistant design followed for buildings in GASCO plants incorporates a practical approach blending past experiences with best known practices in the industry. Building Blast Design Requirements (BDR) data sheet is introduced at early stages of the project and specific requirements such as blast load parameters, building configuration, structural system & foundation type, building response range and other special requirements are developed and firmed up before the commencement of detailed design.
Single-storied regular shaped buildings with no windows or minimum windows with special features are preferred. Elevated ground floor is permitted in certain cases such as Substation to create cable vault. However this presents unique challenges in establishing blast pressure distribution due to lack of guidelines for such set-up, which is overcome by own novel solutions.
For low blast loads, simplified static approach is adopted for structural analysis, while dynamic analysis with SDOF approach yields economical design for medium to high blast loads. In specific cases where SDOF idealization is inappropriate (as in multi storied building), a MDOF non-linear FE analysis is carried out.
RC framed structure with reinforced masonry walls, or steel structure is adequate for low blast, while RC shear wall structure is found most effective to sustain moderate to high blast.
The paper presents best practices and unique approach followed in GASCO for such design amid growing challenges of achieving high performance at low cost. These requirements are common for similar expansion projects and hence can be adopted across the industry.
Effective Use of Reservoir Surveillance to Optimize Production in a Complex Stacked-Sand Oil Field
Authors: Laoroongroj A. , Last N. , Ali A. Bu 
Published: November 2017

Abstract
This paper discusses how surveillance data are collected and integrated to assess the effectiveness and optimize the management of an offshore waterflood, and describes how an enhanced understanding of well performance, flow behaviour and reservoir architecture is used to optimize production and injection.
A comprehensive reservoir surveillance plan is essential in order to understand reservoir behaviour and to optimize ultimate recovery. Multiple surveillance techniques are used including pressure build up and fall off tests, production logs, cased hole formation resistivity and saturation logs, and wireline formation pressure measurements which provide critical information on reservoir connectivity in wells drilled after production start-up. Voidage replacement ratio (VRR) is carefully tracked in each reservoir unit. Hydrogeochemical modelling is used to understand the water chemistry interaction between injected water and formation water, and diagnostic methods such as Hall plots are used to assess injection well performance before and after well stimulation.
Several challenges have arisen since the first wells were put on production. Two of the most significant have been, firstly, to maintain water injection for voidage replacement and, secondly, to understand the reasons behind unexpectedly early water breakthrough at the producing wells. Two case studies illustrate how information from well surveillance has guided the response to these challenges.
Characterization of Fault Damage Zones and Associated Fracture Networks and Their Influence on Fluid Flow in the Tight Carbonate Reservoir
Authors: Shen Feng , Torres Marcos , Mosqueda Francisco , Gutierrez Jose Carmen , Guevara Fernando , Wu Shengyu 
Published: November 2017

Abstract
In the tight carbonate reservoir located in onshore Mexico, fault damage zones and associated fracture networks represent major permeability structure and greatly affect fluid flow. In this study, we present a method for characterizing and modeling fault damage zones and fracture networks. The main objectives are to use fault damage zone and fracture network models to predict fluid-flow pathways in the reservoir and to understand their impact on well production performance.
Appropriate geometric attributes are used for unsupervised seismic facies classification with the aim of delineating fault damage zones. The utility of the facies approach lies in its capacity for classifying the fault system with distinct classes based on the degree of fracturing. The three-dimensional fault damage zones are extracted and modeled from the seismic facies volume. A natural fracture network model in the target formation is deterministically built by meshing fracture lineaments that are automatically tracked along depth slices of the edge-enhanced curvature attribute. The fracture network model provides fracture characters in terms of fracture orientation, length, density and connectivity. Local fracture network models at individual wells can be built using fracture connectivity analysis technique.
The fault damage zone model delineates fault zone architecture and spatial variability. Our results show that the main fracture sets parallel or subparallel to the fault zone strikes regionally. Fractures distribute surrounding fault damage zones with enhanced fracture density. A good correlation between the fault damage zones and the lost circulation is observed. Based on the production data, fault damage zones can act as fluid conduits. In some instances, fault damage zones can create flow barriers. Conditioned with well data, the conductivity of the fault damage zones and related local fracture networks is calibrated. Using the local fracture network model, the fluid flow pathways and fracture vertical connectivity are determined. With borehole breakouts and drilling induced fractures, the identified maximum horizontal stress orientation is in the NNE direction. Our results show that the conductive properties of fault damage zones and fractures could be affected by the stress state and in situ stress orientations. This explains the fact that the wells located in the fault damage zones and fractures with the orientations preferable for extension tendency or slip tendency have high productivity.
The continuous fault damage zone model and the discrete fracture network model can be used to capture 3-D complexity of fluid flow in fault damage zones, improve the prediction of flow pathways and help the lateral or horizontal well design.