bluuebunny/crossref_metadata_2025_split huggingface dataset:
Managing Sulphate Reducing Bacteria (SRB) Problem Associated With Produced Water in One of the Oil Fields of Oil India Limited - A Case Study
Authors: Nihalani M.C. , Verma S. , Kumar J. , Dubey H. , Bharali N.K. , Mandal A.K. , Lal B. 
Published: January 2010

Abstract
In OIL, produced water is normally disposed into Alluvium sand reservoirs at shallow depths. While the disposal depths were in the ranges of 500 – 800 m till recent times, current statutory regulations require disposal to be carried out at depths below 1,200 m to ensure minimal risk of upward migration of such disposed water. In most of these disposal wells, injectivity had been found to be comparatively lower and rapid decline in injectivity is observed even after acid / solvent stimulation.
The presence of SRB was confirmed through API RP 38 standard procedure. SRB related corrosion was also observed in formation water handling and processing infrastructure. Solids generated due to high SRB activity along with high oil content and other suspended solids present was the primary cause of rapid decline in injectivity in these deep disposal wells. The entire problem was taken up for detailed study and identification of remedial measures jointly with a reputed microbial laboratory, M/s The Energy and Resources Institute (TERI), New Delhi, India.
Laboratory investigations included identification, characterization and isolation of various strains of SRB using 16S rDNA gene sequencing and designing different media compositions for inoculation and culturing of SRB strains. Microbial diversity of hyper thermophilic SRB in various produced water samples collected from different points were studied in details.
Through this study, suitable bactericides were identified and Minimum Inhibitory Concentration (MIC) optimized using Time Kill Test (TKT) method. The identified biocides were successfully field tested. The entire produced water from the said field is now being safely managed and disposed underground with sustained injectivity of disposal wells. The present paper discusses the results of laboratory findings and detailed field implementation data, for SRB control in the produced water disposal system.
Cement-Sheath Wellbore Integrity for CO2 Injection and Storage Wells
Authors: Takase Koji , Barhate Yogesh , Hashimoto Hiroyuki , Lunkad Siddhartha F. 
Published: January 2010

Abstract
It is critical that CO2 injection and storage wells have wellbore integrity to help prevent leakage of CO2 during the injection period, as well as long-term zonal isolation to sustain the loading conditions of pressure testing, completions, injection, shut-in, and stimulation treatment. This paper highlights the salient engineering design features of planning a successful cementing-job operation for extended-reach drilled (ERD), carbon capture and storage (CCS) wells.
Corrosion in Portland cement caused by carbonic acid is a well-documented phenomenon. CO2 injected into geologic formations for underground storage purposes can be converted into various concentrations of carbonic acid with different levels of pH in the formation water surrounding the well, depending on conditions such as temperature, pressure, and the formation rock chemical components. The use of non-Portland cement is often recommended in harsh environments (pH&lt;4) to help avoid any negative impact on long-term well integrity. In addition, the cement should have long-term mechanical resiliency against the anticipated future loading conditions of pressure testing, completions, injection, shut-in, and stimulation treatment.
A detailed transient wellbore-temperature analysis was carried out for estimating the wellbore and tubular fluid-temperature profiles during the planned well operations. Based on the estimated temperature profiles, wellbore-pressure conditions, and fluid properties, a rigorous cement-sheath mechanical-integrity analysis was performed following a finite-element analysis (FEA) approach. It was found that the use of non-Portland cement alone might not be sufficient for long-term wellbore integrity. Customized non-Portland cement systems were developed with modified mechanical properties to help ensure appropriate mechanically resilient properties for the long life of a CCS well. Comparative FEA with non-Portland cement and mechanically modified non-Portland cement at the top of tail cement and casing shoe for ERD CCS wells is detailed.
Reconciliation—An Inevitable Challenge in Upstream Oil Industry
Authors: Chebiyyam Chandrasekhar 
Published: January 2010

Abstract
Crude oil is measured at different stages of its flow – i.e.., out of the wells, to Crude oil collection, processing, storage and dispatch installations (GGS - Group Gathering Stations, CTF - Central Tank Farms, CTP - Custody Transfer Points), into tanks & pipe lines, either for flow rate or for inventory positions.
It is a common observation in oil industry that no two meters match exactly. In cases such as crude oil transfer from one location to the other, invariably, the dispatching and receipt meters do have a discrepancy, and sometimes by big margins. This is the point where reconciliation steps in. As long as the differences are within a preset limit, normally caused due to known factors like temperature fluctuations, the difference can be acknowledged as an acceptable reconciliation loss but if the difference is large, this could be due to an abnormal cause such as pipeline leakage or pilferage that needs to be attended immediately. Reconciliation between every two nodes of a crude oil flow provides vital information, not only as a daily tally of crude oil but also as a monitoring tool for the overall chain of flow.
Apart from using elaborate Excel worksheets, previous work in this area has been on the development of stand-alone oil accounting systems specific to Refinery boundaries for monitoring reconciliations and mass balance of oil products, and involves considerable costs. This paper analyses the reconciliation aspects specific to upstream oil industry and suggests a mechanism to monitor these differences between any & every two locations of the crude oil flow, using an ERP package as a backbone, at practically no additional cost.
Systematic Surveillance Techniques for a Large Miscible WAG Flood
Authors: Panda Manmath , Nottingham Derek , Lenig David 
Published: January 2010

Abstract
Miscible water-alternating-gas (WAG) flooding has proven to be an attractive enhanced oil recovery (EOR) method the world over. Successful WAG floods can yield 5-20% additional oil recovery over waterflood because of improved microscopic displacement efficiency by the solvent coupled with improving areal and vertical sweep efficiency through the managed-mobility nature of the WAG displacement process.
WAG floods are complex in nature since reduction of residual oil in the pore spaces depends on mass transfer. Maintaining miscibility between the injected gas and the reservoir oil over a large rock volume is challenging. This challenge is more manageable in a small-scale pilot flood or a core flood than a large field implementation. Numerical simulation efforts can provide guidance to designing an optimal flood. However, the field application will often reveal challenges that are not discovered in the pilot stage or by the full field simulation model because the geologic properties and heterogeneity of the reservoir rock is not accurately represented. Sometimes the incomplete understanding of the PVT characteristics, such as fluid interaction and miscibility, or rock properties, such as wettability and capillary pressures, can exacerbate the challenges.
Integrated surveillance of a WAG flood is the only means to determine whether the flood is working efficiently and the planned additional recovery will be delivered. A well implemented surveillance plan allows timely intervention to improve the efficiency of an underperforming WAG flood.
This paper presents a systematic approach for applying EOR surveillance tools and methods in large miscible WAG floods in the Ivishak reservoirs at the Prudhoe Bay and Eileen West End of the North Slope, Alaska. Highlights of these surveillance methods are (1) designed and implemented by a multi- disciplinary team, (2) based on proven theory and corroborated with field data, (3) requires easily obtainable and relatively inexpensive field data and analysis, and (4) applied from fault block down to zone levels. Implementation of these tools has helped to identify efficient flood patterns and areas of poor performance, which then can be modified through infill drilling, well recompletion, or WAG ratio modification to maximize EOR recovery.
Impact of Increasing Anthropogenic CO2 and CH4 Gases Emission on Cooling of the Earth's Climate
Authors: Sorokhtin O. G. , Chilingar G. V. , Khilyuk L. F. , Haroun M. R. 
Published: January 2010

Abstract
The global climate change issue has the highest priority on the current agenda of the World community because of the global warming trend during the 20th Century. Conventional theory of global warming states that heating of atmosphere occurs as a result of accumulation of anthropogenic CO2 and CH4 in the atmosphere. The writers show that rising concentration of CO2 should result in the cooling of climate instead. The methane accumulation has no essential effect on the Earth's climate. Even significant releases of the anthropogenic carbon dioxide into the atmosphere do not change average parameters of the Earth's heat regime and the atmospheric greenhouse effect. Thus, accumulation of small additional amounts of carbon dioxide and methane in the atmosphere as a result of anthropogenic activities has practically no effect on the Earth's climate.
LNG Smart Air Vaporization Technology Applied to Floating Regasification
Authors: Walther Susan 
Published: January 2010

Abstract
Onshore LNG import and regasification terminals face potential environmental, permitting, cost and schedule issues that can be avoided by use of offshore floating LNG regasification units, FSRUs. The regas technology typically used in a FSRU depends on burning gas or utilizing open loop sea water for the source of heat of vaporization. Burning gas has an environmental impact to the air and the cost of consuming gas that could be sold. Using sea water imposes thermal and chemical impact on marine life. LNG Smart® Air Vaporization (SAV) is an alternative technology that transfers heat from ambient air to the LNG which reduces gas usage and air emissions dramatically, uses no sea water and creates no water pollution.
SAV offers the following advantages: Reduced energy consumption – The proprietary air exchange process offers significant reductions in fuel gas use, from 40-100%, depending on ambient conditions, which results in less shrinkage of the LNG needed for vaporization which is potentially an enormous savings for operators.Lower air emissions - With reductions in fuel gas use, SAV reduces emissions levels on the same order of magnitude as the lower fuel gas consumption.Reduced OPEX - Substantial savings can be demonstrated using SAV. With an onshore Gulf of Mexico 1 bcf/day sendout rate facility, using SAV, with natural gas prices at $6 mmbtu, cost savings with a 90% fuel gas reduction is approximately $25,000,000/year over gas fired technology.Easier permitting – The proven air emissions reduction facilitates permitting.Standard components – While SAV and its configuration are proprietary, virtually all operating components are readily available, shortening construction schedules.Industry-Proven: SAV has been installed onshore and the components have been proven offshore in similar service.Applicable to floating units: SAV can be used on new build or converted reinforced membrane, SPB tanks, or Moss spherical LNG carriers. DNV has given Approval in Principle for utilization of SAV on a FSRU.
This paper explains the LNG Smart® Air Vaporization process and its advantages and gives examples of studies done to utilize SAV on various FSRU hull types.
Management of Change, Key Component of an Effective HSE Management System
Authors: Ershaghi Iraj , Gunasekaran D. Chinnappaaraja 
Published: January 2010

Abstract
Optimum placement of in-fill wells in mature fields requires reliable information about reservoir properties, fluid property distribution and the pressure support of aquifer. In this paper the use of production data is examined as a means of identifying sweet spots for infill directional or extended reach wells. In particular, our focus is the use of production data for fractured reservoirs producing from the Monterey Formation. The emphasis has been mapping of reservoir compartments. Using more than 35 years of historical data on the performance of a number of fields, we have completed a study on the sensitivity of well performance to the size and permeability of compartments, support of aquifer and the matrix or microfractures. This approach can help in identifying cluster of wells with similar compartmental features leading to identification of sub-seismic faults and high productivity compartments and can help in designing the incidence angle of the trajectories of new extended reach and directional wells to intersect compartments with high density fracture swarms.
Innovative Kill and Salvage Operation Successfully Completed in Bay of Bengal with No Hse Incidents
Authors: Curtis Bud , Nutt Joe , Elkins Dave , Ahuja Sunil Kumar , Bhatt Sanjay 
Published: January 2010

Abstract
This paper describes the decision-making process and on-the-fly design strategy that paved the way for the successful and incident-free execution of a uniquely engineered kill and salvage operation in the Bay of Bengal. The seven-month project employed a 150 HP Remotely Operated Vehicle (ROV) to successfully secure a storm-damaged well and recover a 217-ton BOP stack from more than 800 ft of water.
The kill and salvage operation was initiated after a late-summer depression that generated surface and subsurface currents as high as 4.5 knots, eventually severed the riser near the BOP stack on the operator’s Sagar Bhushan drillship, which was completing the ONGC G-1-DB well. The unparalleled project overcame numerous technical challenges to unconventionally kill the well via stinger and retrieve the BOP, subsea tree and wellhead, while averting any potentially catastrophic HSE incidents.
The complexity of the operation was underscored with the on-location designing of an unprecedented procedure and specialized tools to kill the well where all post-storm subsurface components, including the BOP stack and drill pipe, were buried and resting horizontally. Practically all of the tools required had to be customized and fabricated on-board either the ROV-deployment vessel or drillship. These included everything from the customized stinger used to kill the well, to the cutters and heavyweight slings needed to raise the BOP stack.
The authors will systematically review the operation and the close communication between the operator and service provider that resulted in the decision to employ the unique kill and salvage procedure.
Use of KCl-Polymer Clouding Out Polyol Drilling Fluid in Combating High Pressure in Deep Exploratory Wells of Assam Field: A Case Study
Authors: Kumar Shyam , Kachari Jnan 
Published: January 2010

Abstract
Use of Low Solids Potassium chloride - Polymer Inhibitive drilling fluids emerged as an answer to minimize drilling related problems arising from sensitive clays and shale such as borehole instability, torque, drag, build up of low gravity solids, bottom hole fill, stuck pipe attributed to clay/shale hydration. Further improvisement of this drilling fluid system has been done by incorporating clouding out Polyol (equivalent to Clouding out Glycol) for enhanced inhibition and borehole stability. In ONGC it is extensively used successfully to drill high tech wells such as high angle /high drift / horizontal wells in development fields. Exploratory wells are mostly being drilled using dispersed drilling fluids to exploit the convenience of achieving higher drilling fluid specific gravity but wash outs have been problematic in Assam Fields especially in deep shale-coal- sand stone alterations.
Penetrating through troublesome shale coal sequence poses formidable challenge in smooth well completion. ONGC Assam Asset after careful selection used KCl-Polymer Clouding Out Polyol drilling fluid in deep exploratory wells in Assam field. Performance of this drilling fluid in providing borehole stability and more importantly attaining and sustaining higher fluid specific gravity in drilling and in combating well activity has been eventually established. More than five deep exploratory wells have been successfully drilled and two are being drilled in critical interval. Out of these activity in three wells have been successfully subdued using this system with high specific gravity up to 1.9 at the time of writing this paper. Further Pilot test has favourably indicated that given opportunity the above fluid will hold satisfactorily to specific gravity 2.0 without pumpability and Barite sagging problem.
Performance of KCl-Polymer Clouding Out Polyol drilling fluid in drilling especially shale coal-sand/shale-sand sequence of deep exploratory wells in Assam field and the benefits derived out of it have been discussed in this paper.
Successful Hydrofracturing Campaign Leads To Commercial Development of Tarapur Field in Gujarat
Authors: Ramanathan V. , Pankaj P. , Susanta P. H. , Dubey S. , Farooqui M. Y. , Chauhan S. P. , Singh P. 
Published: January 2010

Abstract
In today’s challenging world of exploration, Hydro Fracturing (HF) is an important tool in the oilfield arsenal that enables operators to understand the formation potential deliverability. More and more companies today are adopting hydrofracturing as part of the exploration strategy for better quantification of hydrocarbon production. GSPC decided to precisely do this in their Tarapur asset due to very low rates of production post drilling phase.
GSPC has drilled quite a few wells in the Tarapur field which is located near the Ahmedabad city. In order to verify the ultimate producability of these formations, hydraulic fracturing is the most suitable strategy. 6 wells, which showed presence of oil, were chosen as the stimulation candidates for the production enhancement and production potential identification from this field. This project primarily focused on the exploration and development of the Kalol Sand of the Tarapur field.
The entire HF operation consisted of two parts known as the Datafrac and the Main Fracturing Treatment. Datafrac was done to estimate critical formation and fluid parameters such as like fracture closure pressure, Fluid Efficiency and Leakoff Coefficients which all are determined to design the most optimum job for maximizing ultimate recovery. Reservoir transmissibility validation was also performed via the injection test that is done as a part of the Datafrac injection test.
This paper discusses the planning and design processes leading to the successful execution of the hydro frac treatments and the post-stimulation results. The experience and lessons learned during the stimulation treatment design, execution and post-stimulation results will be discussed. Lessons learned from this successful experience are discussed as a way to enhance the benefits from this promising technology that will lead to more successful developments of the exploration wells in India.
Understanding the Distribution Pattern of Prospective Reservoir Facies: A Sequence Stratigraphic Approach for Integrated Characterization of the Tarapur Field; Cambay Basin, India
Authors: Farooqui M. Y. , Ghosh Ujjwal , Shrivastva Chandramani , Shasmal Sudipan , Bora Deepender , Dubey Sharad , Bhadra Sutapa 
Published: January 2010

Abstract
The Cambay Basin in western onshore India has been on production for a long time and most of the easy-to-find reservoir facies are being exploited by different operators. However, the complex setting of the basin provides opportunity for exploration of many other reservoir facies distributed throughout the basin. Tarapur field is located in a relatively lesser understood part of the basin and understanding the distribution pattern of prospective reservoir facies in this field has been a challenge for optimal exploitation of this area.
An integrated approach has been developed to understand the complexity of the reservoir in a sequence stratigraphic framework integrating the geosciences data from different domains. Borehole images, conventional openhole log data, mud log, nuclear magnetic resonance and background geological information have been incorporated and integrated with seismic backdrop to understand the signatures of geological agencies on the formation across different scales which govern the distribution and geometries of the facies.
Different lithofacies were identified with the help of master log and conventional open hole logs, incorporating the finer textural details from borehole images. The artificial neural network methodology helped in properly differentiating the sub-facies and provided a firm basis for extrapolating the facies associations across different wells of the field. The association of these lithofacies and their orientation derived from the dip data revealed the possible assemblages of depositional sub-environments encountered in a single well. Facies assemblages are mainly comprised of silt, shale and coal lithofacies. These are vertically distributed with a specific fining and coarsening upward trends which are in turn inferred in terms of depositional sub-environments. The study reveals different stages of sediment build up and their vertical facies stacking pattern leads to the identification of two parasequences. By extrapolating the interpreted facies model honoring the petrophysical properties in nearby wells, a good control on the conceptual geological model is achieved. Based on facies association analysis, marginal marine sedimentary environment is envisaged. The stacking pattern of facies associations is interpreted in terms of prograding parasequences which are also identified in seismic line validating the conceived depositional model. This sequence stratigraphic framework provides the predictive value to the model for reservoir facies distribution.
Being the first of its kind in the field, this study provides a methodology that aids in the optimization of exploration strategy. The high resolution seismic attribute analysis coupled with the conceptual model would help in locating the new exploration leads.