bluuebunny/crossref_metadata_2025_split huggingface dataset:
Prediction of Toxicity Effects of Oil Field Chemicals Using Adaptive Genetic Neuro-Fuzzy Inference Systems
Authors: Ibrahim H. D. , Odedele T. O. 
Published: April 2018

Abstract
Chemicals are used in various stages of oil production such Drilling (Drilling fluids, cementing, completion and workover fluids), Production, Stimulation and Enhanced Oil Recovery. Many research studies have shown these oil field chemicals have toxic effects on the environment. The oilfield chemicals include various additives for drilling/cementing and work-over such as Fluid loss additives, rheology modifiers, Viscosifiers, Emulsifiers, Biocides, Surfactants, Packer fluid corrosion inhibitors. Toxicity tests are crucial for the assessment of the harmful effects of complex chemical mixtures, such as waste drilling mud, hydraulic fracturing fluid on aquatic environment. The objective of the study is to develop screening protocol to assess, evaluate, and manage the inherent risks. To achieve this, it is imperative to develop models, tools and an acceptable mechanism for screening, predicting and monitoring the application of oil field chemicals. In this paper, Adaptive Genetic Neuro-Fuzzy Inference System is developed to assess the toxicity of oilfield chemicals. Several toxicological studies have shown the evidence of toxicity of some oilfield chemicals to living organisms and their potentially negative side effects on environmental ecosystems for which relatively tedious animal testing methodologies are documented for their assessment. The description of this intelligent system is provided and has proven to have better classification and regression capability and ability to handle high dimensional features. This study adopts a novel evolutionary computing approach to search and obtain the optimal Neuro-Fuzzy parameters to enhance the prediction accuracy and generalization capability of the model. The system was applied to a dataset on Oil Field Chemicals toxicity and it was found that the genetic algorithm yields optimal parameters of Neuro-Fuzzy for the given datasets. The prediction and classification of Oil Field Chemicals (toxic or non-toxic) using this hybrid intelligent system is a work that requires an in-depth study and understanding of the various underlying principles of Neuro-Fuzzy inference system and Genetic Algorithm, which is commonly applied for classification and regression purposes. The developed model based on the fuzzy rules was trained with available data set. The unseen or new data is therefore either classified into appropriate class or have toxicity predicted using gaussian membership function chosen for this application. The motivation of this approach is that it is less cumbersome than the conventional computational modeling usually adopted for chemical classification and characterization. It also seeks to eradicate the existing animal testing that are hitherto very tedious and cumbersome.
How to Plan a SAGD Project, If You Must…
Authors: Farouq Ali S. M. , Byestehparvin Bita 
Published: April 2018

Abstract
Steam-Assisted Gravity Drainage (SAGD) is widely used in Alberta for recovering bitumen from oil (tar) sands. A variation of the same has had some success in heavy oils as well. It is a high-risk recovery method and requires careful planning and design. This paper outlines the success criteria for SAGD, and a design methodology.
First of all, applicability of other lower risk recovery processes, such as steamflood variants, is considered to determine if SAGD is a good choice. SAGD has been successful in oil sands of Alberta under rather restricted conditions. Geology is the most important factor, in particular vertical permeability, oil saturation, and initial mobility of water. Where the minimum criteria are not satisfied, there have been failures, discussed also. The author has developed new equations for the entire SAGD process, not just the stabilized oil flow regime, given previously, and has corrected the errors in the same. These are discussed in detail, with examples. The application of SAGD variations in conventional heavy oils is also considered.
The current experience in Alberta, and elsewhere, is described, and reasons for success/failure are outlined. Given that background, the desirability of SAGD vis-à-vis other thermal processes is discussed for California heavy oils. The variation of SAGD being employed in Saskatchewan heavy oils is also discussed, showing that it is not SAGD in the strict sense, rather a modified steamflood, using horizontal wells. It is concluded that SAGD has a high oil recovery potential if the right combination of rock-fluid properties is present. The application of SAGD to conventional heavy oils is equally problematic, in view of a very different mechanism.
The novelty of the paper lies in (1) a comprehensive treatment of SAGD, from the rising chamber to plateau to decline phases, (2) assessment of SAGD compared to other recovery methods for different types of reservoirs, and (3) application of SAGD variants to conventional heavy oils.
Enhanced Proppant Suspension in a Fracturing Fluid Through Capillary Bridges
Authors: Quintero H. J. , Mattucci M. , O'Neil B. , Folkes G. , Zhang K. , Wang C. Z. , Lu W. 
Published: April 2018

Abstract
The development of tight oil and gas shale relies heavily on multi-staged hydraulic fracturing, with the objective being to induce a complex network of interconnected fractures (artificial and natural), effectively created by water-like viscous fluids and sand laden slurries injected at very high pressures and rates.
Numerous methods have been employed to reduce sand settling and duning during hydraulic fracturing. Conventionally, frac designs have relied on injection rate, and viscoelasticity of the fluid to offset sand, or proppant settling. As of late, development in proppant technologies have focused on introducing alternative engineered materials for proppants that feature oil field brine pseudo specific gravity (S.G.), while maintaining mechanical strength, therefore relying on the buoyancy effect for proppant transport; despite all these efforts, proppant suspension remains a burden for the fracturing fluid.
Herein, we report a pioneering fracturing fluid where through inducing capillary bridges proppant sands become part of the fluid structure and are no longer the burden to be carried. This new fluid system offers a unique and superior proppant transport mechanism, under a wide range of shear stress and rate conditions, without the need for conventional polymers and/or cross-linkers.
This field-proven and cost-effective fracturing fluid features a non-damaging synthetic polymer. Field cases show successful placements of proppant where other conventional fracturing fluids have failed/screened-out.
Regained permeability analysis indicates ≥100% regained permeability when Bandera sandstone (~1 - 10 md permeability) core samples were tested. Proppant settling test analysis showed no proppant settling in a 5 hour period when 500 kg/m3 (4.17 lb/gal) of 30/50 U.S mesh size proppant laden slurry was tested, simulating a bottomhole temperature (BHT) of 70°C (158°F). Also, a more than 33% increase in sand pack volume in the slurry was observed during the aforementioned analysis when compared to a borate-crosslinked guar slurry counterpart.
This paper intends to detail the development, laboratory testing and field cases of this novel fracturing fluid, that has been successfully pumped in more than 150 frac stages in the Western Canadian Sedimentary Basin (WCSB).
An Integrated Workflow Approach to Manage Steamflood Operations
Authors: Jones J. A. , Dwivedi P. 
Published: April 2018

Abstract
A rapid, user-friendly & easily deployable workflow solution for managing steam flood operations & reservoir management is presented that combines day to day surveillance techniques with performance prediction that uses an analytical model for proactive management of operations.
The proposed workflow has been implemented in multiple projects (using public data and data provided by operators) to answer multiple critical questions like pattern response date, steam breakthrough time, expected peak rate from a pattern, arrival of the peak rate, underperforming or over-performing regions in a field, redistribution of the steam volumes, where to minimize steam oil ratio, classify patterns based on efficiency and so on.
It is built up on two core components. A set of diagnostic plots and data analytics that enable quick historical performance assessment of patterns as well as the surveillance of the current state of operations. Secondly, an analytical performance model by Jeff Jones is applied to model the oil production from the patterns (early time, mid-life and late pattern life) that serves as a fast-computational tool for practising engineers. This paper discusses the results from multiple fields on the application of proposed workflow and how it has assisted in field management and optimization. These methods are efficient and fast and more importantly user friendly for reservoir management of steamfloods.
Towards a Discontinuous Galerkin Thermohydromechanical Simulator for Heavy Oil Recovery
Authors: Meguerdijian S. , Jha B. 
Published: April 2018

Abstract
Thermohydromechanical effects can have significant impacts on the operations of heavy oil and geothermal fields. This motivates the use of accurate reservoir simulators in field development planning. Previously, simulation using continuous Galerkin methods was examined. However, these methods can experience difficulty in convection-dominated flow problems. Consequently, the discontinuous Galerkin method was considered as an alternative. The discontinuous Galerkin method's literature suggested the need to state a generalized, single-phase thermohydromechanical formulation to clarify previous work. This paper states this generalized formulation and performs a poromechanical benchmark of uniaxial compaction in FEniCS using the discontinuous Galerkin method. Additional work on extension to multiphase flow and the incorporation of thermal effects is needed.
Permeability Prediction in a Heterogeneous Reservoir Using Soft Computing Technologies
Authors: Zhao Xiaoxi , Popa Andrei , Ershaghi Iraj , Aminzadeh Fred , Casidy Steve 
Published: April 2018

Abstract
Permeability is one of the most important parameters in reservoir characterization. Core measurements are usually used to provide this information. However, core data can be limited in certain locations and is expensive to collect. Various methodologies have been used in the industry to predict permeability through porosity or other information with limited success. In this paper, a workflow has been proposed to first identify the relationship between well logging and core permeability data. Using various data mining methods, data preprocessing and filtration are conducted to detect outliers and to ensure the success of permeability prediction. A case study of a heterogenous reservoir has been conducted with this proposed method. Preprocessing results were compared with additional geological and geophysical information in order to understand data behavior. An artificial neural network was applied to train the model by using well logging information as the input and permeability values as the output. Different data normalization methods, input data combination, training function and different neural network architectures were tested in order to get better performance with reasonable time consumption. Prediction results showed consistency in predicted verses true permeability. The study showed that, for a rather heterogeneous reservoir, Artificial Intelligence can provide consistent permeability prediction with well logging data which can help in the decision-making process.
It should be noted that this study is not unique, similar work has been conducted and is available in the literature. What is noteworthy about this study is that this method provided a significantly improved permeability estimation compared to the classical regression models available in modeling software applications such as Geolog
Single Phase Microemulsions Applied to Oil Sands
Authors: Sharma P. , Kostarelos K. , Xiong X. 
Published: April 2018

Abstract
Extra–heavy oil sands deposits represent a significant part of the oil resources available all around the world. Current recovery techniques such as open pit mining, SAG-D, etc., are not very efficient and have been debated for their possible adverse effect on environment. We propose a method of oil recovery that has the potential of being a "game changer" for such resources: using cyclic injection of surfactant solutions forming single–phase microemulsion (m.e.) without mobilizing the oil. This type of m.e. has several advantages: it is less viscous than the extra heavy oil/bitumen; when the surfactant is injected, the m.e. can finger through the tar to a production well, where it will contain a high mass of heavy oil and can be transported without addition of diluent. This approach would use two parallel horizontal wells as an injector/producer pair so that injected surfactant solution would create viscous fingers/flow paths through the oil sands. The m.e. formed during the process would be produced in the second well. After transportation, the surfactant will need to be recovered from the m.e. and recycled for re-injection.
Phase behavior experiments such as surfactant screening, salinity scans and aqueous stability were conducted focusing on forming single phase m.e. Previous work aimed at single phase m.e. used coal tar as a model oil for phase behavior studies and flow experiments that yielded promising results. As a result of the previous work, new phase behavior studies were conducted using bitumen extracted from oil sands obtained from Alberta, Canada that are presented in this paper. Three flow experiments were conducted using a surfactant formulation selected based on the results of the phase behavior experiments to recover bitumen from the oil sands.
For bitumen, single phase m.e. was achieved with a mixture of internal olefin sulfonate and alcoxy sulfate (1:1) surfactants with alkali (sodium carbonate), with bitumen solubilization of the order of 300,000 ppm. The three flow experiments were conducted to explore two different flow schemes, to compare a synthetic oil sand (bitumen from oil sands mixed with OK-75 sand) with an actual oil sand, and to investigate the effects of two experimental setups. The recoveries from these flow experiments were lower than expected, only achieving a bitumen solubilization of the order of 10,000 ppm. The analyses of the results and possible reasons for lower recovery are discussed in the paper.
Surfactant solubilization method using single phase m.e., could provide an environment-friendly alternative to current recovery methods. It would also eliminate the need of adding solvents for transportation. While improved surfactant formulations could yield better recovery, the economic feasibility of the process will depend upon the final step—recovery of the surfactant from the produced m.e. Work is currently being conducted on several potential surfactant recovery processes.
Clay Stabilizers Performance in a Comprehensive Matrix of Bentonite and Silica Flour
Authors: Aften C. W. 
Published: April 2018

Abstract
A systematic study of various temporary and permanent clay stabilizers was conducted with assorted binary blends of bentonite and silica flour. A specific stabilizer's performance is directly correlated to the type and loading of the inhibitor and particular ratio of existing inorganic substrate. Results exhibited high performance correlation; response surface general topography is dependent upon the temporary or permanent characteristics of the stabilizer.
Studies comprised combined mixture, single numeric, optimal, design of experiment and performance test data gathering utilizing a low-pressure fluid loss cell. A predetermined concentration of unadulterated sodium bentonite and 325-mesh silica flour were blended into water at a specific RPM and duration in the presence of a particular stabilizer then placed into a the cell, sealed, and pressure was applied. Increased Darcy leak off slope values are reliable, accurate indicators of increased stabilizer performance thus each slope was calculated and plotted versus stabilizer dosage and inorganic substrate ratio.
KCl was studied from 0 to 8 weight percent and used as a comparative guide for all stabilizers tested with the balance tested in their "as is" state from 0.0 to 2.0 gallons per thousand gallons. Temporary stabilizers typically provided a consistent topography with respect to performance, with a 20/80 bentonite/ silica flour ratio yielding the highest performance. Bimodal maximum performance inorganic ratios were present for permanent stabilizers tested. KCl dosage offset lab results correlate well with reported field application results. At higher stabilizer loadings superior performance relative to KCl was evident.
Traditionally clay stabilizer selection is based upon Capillary Suction Time and Roller Oven testing methods. This alternate bentonite and silica flour comprehensive matrix clay stabilizer selection method is consistent, continuous, portable, field friendly and applicable over a wide range of stabilizer and variable inorganic matrix types.
Nanoparticle and Surfactant Oil/Water Emulsions - Is Different Treatment Required?
Authors: Gavrielatos I. , Dabirian R. , Mohan R. , Shoham O. 
Published: April 2018

Abstract
Experimental observations regarding the formation of oil-water emulsions stabilized by nanoparticles and surfactants during oil production operations are presented. Similarities and differences between the two types of emulsions are discussed based on acquired separation profiles, as well as respective fluid interfacial properties. A state-of-the-art, portable Dispersion Characterization Rig (P- DCR) is used to run the experiments and a surveillance camera is deployed to monitor emulsion separation kinetics. Commercial grade mineral oil and distilled water are used as the test fluids. Silica nanoparticles of different wettability and surfactants with different HLB values are deployed to investigate commonalities/differences between surfactant and nanoparticle stabilized emulsions.
Separation profiles were analyzed and similar behavior between the corresponding surfactant and nanoparticle emulsions was observed for the 25% water-cut case. For higher water-cuts, however, the surfactant stabilized emulsions were tighter than their nanoparticle counterparts, displaying much lower separation rates. In the most severe cases, the surfactants totally inhibited the oil creaming process and oil remained trapped in the emulsion for several hours. Multiple emulsions (O/W/O) were observed in certain cases (for hydrophilic nanoparticles and lipophilic surfactants (Span 80)). It appears, based on the aforementioned experimental observations, that the presence of surfactants can cause more severe problems to the oil-water separation process than the presence of an equal concentration of nanoparticles. Pendant drop measurements indicate that the surfactants can lower the interfacial tension between oil and water significantly, whereas the nanoparticles do not have a similar effect.
Current research sets the basis for more thorough investigations aimed at providing guidelines for more efficient operation of separators handling surfactant or nanoparticle stabilized emulsions and better understanding of related phenomena.
An Experimental Investigation into Gravel Pack Performance in Steam-Drive Operations
Authors: Roostaei Morteza , Kotb Omar , Mahmoudi Mahdi , Fattahpour Vahidoddin , Wang Chenxi , Nouri Alireza , Fermaniuk Brent 
Published: April 2018

Abstract
Open hole gravel pack (OHGP) has been broadly used for completion of steam-drive production wells. However, some failures have been observed with the gravel pack in such complex completions. This paper aims to better understand the OHGP performance in steam-drive production wells and examine the performance of rolled-top and straight-cut slotted liners using a large-scale Sand Retention Testing (SRT).
A large-scale SRT facility was developed to investigate the performance of the gravel pack in two-phase flow regime. The testing set-up allows for co-injection of oil and brine at controlled flow rate and water cut level to emulate different scenarios for two-phase flow across the gravel pack and sand screen/liner. Testing measurements included produced sand, absolute pressures, and differential pressure drops across the slotted liner, gravel pack, gravel-sand pack interface and sand pack. The test procedure and test matrix were designed to enable an accurate assessment of the gravel pack and slotted liner performance for different fluid flow scenarios. Rolled-top and straight-cut slotted liner coupons were used for this study.
Test results showed negligible sand production for both rolled-top and straight-cut slotted liners, however the produced sand was slightly higher for the rolled-top profile. The pressure drop across the rolled-top liners were smaller than the straight-cut liners based on the analytical analysis presented in this study. The results have also shown that a key factor in gravel packing performance is the ratio of the gravel pack size to the formation sand (sand pack) size. Larger gravels allow an easier production of the fines, while smaller gravels may trap the fines and be plugged over time.
This work provides a robust testing facility to address the gravel pack performance in steam-drive producer wells. The results help the engineers with gravel pack and sand control design and an evaluation for the entire wellbore life.
Case Studies of an Effective Methodology to Collect Formation Water to Meet Regulatory Requirements for Formation Water Sampling
Authors: Tran V. H. , Arismendi N. , Biswas T. 
Published: April 2018

Abstract
New underground injection control (UIC) regulatory activity come with challenges. California regulatory agencies have enhanced scrutiny on underground injection projects. One of the requirements under the California UIC regulations is to collect formation water samples and submit water analysis results together with the application package to confirm whether the Total Dissolved Solids (TDS) of a formation or aquifer is greater than 10,000 ppm, which is non-underground source of drinking water (non-USDW) under the federal Safe Drinking Water Act (SDWA).
Various methodologies for collecting water samples were evaluated before selecting wireline tools, to collect water samples. The water samples were collected open-hole using downhole special wireline equipment with high technologies to analyze/detect not only fluid types being pumped through tool's flowline but also the contamination levels (due to mud filtrate invasion), to prove the representative formation fluid quality of the collected samples.
This paper summarizes water sampling methods using two different types of wirelines sampling tools from two different leading wireline contractors. Depending on the key sensors each tool has, strategies to detect contamination levels were studied and developed. The following executions and on-the-fly decision making have proved this sampling method is the most suitable and cost-effective for the specific regulatory required sampling.
Formation water samples were successfully collected with monitored contamination levels to prove the accuracy of the formation TDS of this sampling method compared to the log-derived TDS. This crucial data helps demonstrate the TDS and water quality in order to comply with California UIC requirements.
This is a new sampling method that had never been used in the San Joaquin Valley region for formation water sampling. Despite initial concerns from regulatory agencies about the accuracy of this method, the regulators have not only accepted this formation water sampling technology, but now advocate for its use by other operators.