bluuebunny/crossref_metadata_2025_split huggingface dataset:
A New Technique to Confidently Characterize Wettabilty Alterations Induced by Drilling/Completion/Workover Fluids
Authors: Rao D. N. , Bassiouni Z. A. 
Published: December 2007

Abstract
Formation damage, although limited to the near-wellbore regions of the reservoir, plays a major role in productivity impairment simply because all the produced fluids must flow through this region. This damage could consist of permeability reduction due to deposition of particulate matter (fines, mud solids, asphaltenes etc.) as well as wettability alteration. While the permeability reduction and its possible remedies have been well-characterized in laboratory core floods, the wettability alterations induced by the interactions between the rock and the various fluids used in drilling, completion and workover operations have remained difficult to characterize. This difficulty is mainly due to the uncertainty in the techniques we have been using to characterize wettability, which has led to an aura of skepticism surrounding laboratory measurements of wettability. Some of the reasons for this state of affairs are the lack of reproducibility of contact angle measurements even after using live reservoir fluids and long aging times, and the unrepresentative (or non-reservoir) conditions under which the Amott and USBM tests are generally carried out.
This paper presents the recently developed dual-drop dualcrystal (DDDC) technique which has been used successfully in several oil-field applications to generate reproducible measurements of both the water-advancing and water-receding contact angles at reservoir conditions of temperature and pressure using live reservoir fluids. Unlike the conventional contact angle tests, which require 30-40 days to complete, the new technique enables these measurements within 2-3 days while assuring measurement accuracy within about 2-3 degrees.
The paper presents the methodology and salient features of the new technique, some of the recent results to demonstrate its accuracy and short run times, and actual reservoir cases involving serious wettability shifts caused by brine incompatibility, scale deposition, temperature variation and a workover fluid invasion. Due to its accuracy, short run duration and operability at reservoir conditions, the new technique offers excellent potential for detailed understanding of the influence of the various components of drilling/completion/workover fluids on wettability alteration, screening and optimization of fluids for field applications, and evaluation of remedial measures to combat formation damage.
Effect of Carbon Dioxide on Hydrogen Sulfide Scavenging
Authors: Salma T. 
Published: December 2007

Abstract
Effective removal of hydrogen sulfide (H2S) is one of the challenging problems associated with the production of natural gas. Since H2S is often present in natural gas along with varying levels of carbon dioxide (CO2), selective removal of H2S from sour gas in the presence of CO2 is very important for cost effectiveness of a scavenging operation. For over ten years, triazine based scavengers have been successfully applied in the sweetening of natural gas. However, observations of the effect of CO2 on the scavenging capacity of triazine based scavengers have not been very consistent. Initial documentation and case histories on performance of triazine based scavengers by Dillon [1,2] reported that CO2 did not have any effect on the H2S scavenging capacity of triazine. However, recent studies by GRI [3] indicate that CO2 significantly reduces the H2S removing capacity of triazine. To address this discrepency, this paper critically evaluates the effect of CO2 on the scavenging performance of a triazine based H2S scavenger. Results from controlled laboratory experiments, using a wide range of CO2 partial pressure and H2S to CO2 ratios indicate that CO2 has very little effect on the H2S scavenging performance of a triazine based H2S scavenger. Field data supports the observations made in the laboratory experiments.
Reservoir Engineering Aspects of CO2 Sequestration in Coals
Authors: Seidle John P. 
Published: December 2007

Abstract
With increasing worldwide CO2 emissions, interest has risen in injecting CO2 into coals to mitigate their possible role in global warming. Concepts from natural gas storage are readily adapted to CO2 sequestration in coals. The classic p/Z plot for describing stored gas inventories is modified for CO2 sequestration using the p/Z* concept developed for understanding conventional coal gas recovery. Coal often exhibits stress dependent permeability and this relationship is used to identify the optimal depth for CO2 injection. CO2 fillup of a coal seam is described by coupling a gas injectivity equation with a mass balance equation. Example calculations are presented for two selected basins.
Viscoelastic Surfactant Fracturing Fluids: Applications in Low Permeability Reservoirs
Authors: Samuel Mathew , Polson Dan , Graham Don , Kordziel Walt , Waite Tim , Waters George , Vinod P.S , Fu Dan , Downey Rich 
Published: December 2007

Abstract
The introduction of viscoelastic surfactant (VES) base fracturing fluids has changed the way industry views fracturing fluids and proppant transport during a fracture treatment.1 Elimination of polymers allows one to achieve highly conductive proppant packs with no polymer damage. Retained permeability and leakoff control are two of the most important requirements for fracturing fluids. Traditional and new generations of cross-linked gels provide good leakoff control, but they often adversely affect the retained permeability of the proppant pack. In addition, minimizing frac-height growth and increasing effective fracture length are a few other advantages of using VES fluids.2
In the majority of cases in low permeability formations, a long and conductive fracture is the ultimate aim of hydraulic fracturing. Borate or metal crosslinked guar fluids, because of their inherent high viscosity, typically result in height growth rather than increased fracture length. With VES fluids proppant transport is based on the elasticity and structure rather than the viscosity of fluid. Therefore VES fluids efficiently transport proppants at lower viscosities. At the same time, VES fluids let one achieve a better fracture geometry, that with minimum fracture height and maximum fracture length. Pressure transient analysis and tracer studies have shown that this non-damaging low viscosity fluid can give longer effective frac-length even when using much less fluid and proppant volumes (Figure 1). Reduced friction pressure is another added advantage while using VES fluids. Hence VES fluid is the fluid of choice when fracturing is performed through coiled tubing.3,4 Simplicity and reliability of this two component system are the other features of this fluid that attract the industry globally.5
The use of VES technology is now extended to other oilfield applications, such as selective matrix diversion,6 filtercake removal,7 and coiled tubing clean out. VES technology is also defining new engineering practices in hydraulic fracturing that cannot be accomplished with conventional fluid systems, such as fracturing through coiled tubing.
Recent Advances in Laboratory Test Protocols to Evaluate Optimum Drilling, Completion and Stimulation Practices for Low Permeability Gas Reservoirs
Authors: Bennion D.B. , Thomas F.B. , Ma T. 
Published: December 2007

Abstract
Low permeability gas reservoirs often exhibit high resistivity and low initial water saturations. Reservoirs of this type may also be susceptible to problems associated with the retention of water or hydrocarbon based drilling and completion fluids, as well as the accumulation of hydrocarbon liquids from the production of rich retrograde gas systems. These phenomena are referred to as aqueous and hydrocarbon phase trapping and have been extensively discussed in the literature as a major source of reduced productivity in low permeability gas reservoirs. This paper briefly describes specific laboratory procedures which have been developed to diagnose problems with phase trapping for given reservoir applications. This allows for the selection of the optimum drilling and completion fluids and practices prior to the costly execution of a potentially ineffective or damaging treatment in the reservoir. Specific examples of tests results and detailed protocols based on extensive testing and refinement of lab procedures are presented.

Introduction
Phase trapping or adverse relative permeability effects has been discussed extensively in the literature (Refs. 1 to 13) from both a theoretical and field production perspective. This mechanism of formation damage is becoming increasingly recognized as a significant issue in the reduced productivity of low permeability gas wells, and may occur in a number of different areas during drilling and completion operations and subsequent production operations. Most notably, with respect to low permeability gas reservoirs, the areas which are often evaluated on an experimental design basis include:Water-based phase trappingOil-based phase trappingRetrograde condensate dropout trapping and removal.

Water-Based Phase Trapping (Water Blocking, Aqueous Phase Trapping)
Due to the relative preponderance of water-based fluids that are used as drilling and completion media on a worldwide basis, this particular type of phase trap tends to be more common in most situations, and a considerable effort has been made to diagnose and evaluate its effect.
Water-based phase trapping occurs when a water-based fluid is introduced into the reservoir matrix in the region surrounding the wellbore (or in certain situations a natural or induced fracture face), and a portion of this fluid in retained in the rock matrix upon commencing production (or in some cases when initiating injection). The severity of a water trap is highly influenced by:Initial fluid saturations in the reservoirRock wettabilityPore system geometry
New Downhole Tool for Coiled Tubing Extended Reach
Authors: Sola Kjell-Inge , Lund Bjørnar 
Published: December 2007

Abstract
Extending the reach is one of the main challenges for coiled tubing operators, as illustrated by the multiple efforts to develop downhole traction devices for coiled tubing (CT). This paper presents a simple, yet reliable and efficient tool for extending the reach of CT. The tool, called CT Friction Drag Reducer (FDR), is based on a unique patented concept, and uses fluid flow to generate axial oscillation in the CT and bottom hole assembly. As a result, time-averaged friction forces can be reduced significantly. Calculations based on a simple physics-based model predict that the reach can be extended by over 3000 meter in a horizontal well with a measured depth to true vertical depth ratio (MD/TVD) greater than 2.0. Model results match well with full-scale tests. The tool will normally be integrated as a part of the bottom hole assembly (see Figure 1).
The FDR tool has been developed and tested at RF-Rogaland Research (RF) as part of a joint industry project (JIP) with Saga Petroleum ANS and Shell International Exploration & Production B.V. as main industrial sponsors and with co-funding from commercial investors. The FDR tool has an outer diameter of 3.5 inch, is 1.2 meters long and is designed for flow rates in the region of 100 to 900 liters per minutes. Laboratory tests at RF demonstrate the feasibility and functional efficiency of the concept.
Full-scale tests using a 7-inch internal diameter horizontal surface loop at RF have proven the friction reducing efficiency of the concept. In several tests with 600 meter of 1.75 inch coiled tubing and a bottom hole assembly weighing 600 kg, the friction force during run-in and pullout from the 7-inch test well was reduced by up to 90 %. In one case of run-in, the measured friction reduction was 94%.
An acceptance test with 2-inch CT has been conducted at RF using the CT unit at the Well Intervention Test Center to demonstrate and document the endurance of the FDR tool.
The technology will aid in CT intervention and drilling operations, but can also be used in conventional operations such as placing liners in extended reach wells and pipeline operations.
Advantages to Remedial Operations of Coiled-Tubing-Enables Under-balanced Removal of Latest-Generation Composite Bridge Plugs
Authors: Plante Mark E. , Lockhart Robert D. 
Published: December 2007

Abstract
This paper discusses the advantages that accrue to remedial operations as a result of using coiled tubing to enable the fast and safe removal of the latest-generation composite bridge plugs in an underbalanced environment. The paper addresses the development and early field history of latest-generation composite bridge plugs, which are designed to set securely in the casing and then be easily removed using coiled-tubing-conveyed downhole motors and drilling tools in an under-balanced environment after remedial operations are complete.
The new technology is particularly applicable in multi-zone, commingled gas wells with varying bottom-hole pressure, where there is a need to reduce overall operator expense and minimize formation damage, without compromising reliability of safety.
Field experience verifies that a reliable and easily removable composite bridge plug requires substantially less rig time than conventional cast iron bridge plugs while at the same time reducing formation damage. These benefits result from the ability of coiled tubing conveyance to eliminate the need for kill weigh fluid and to enable the well to be worked over "live".
The paper includes a listing with brief descriptions of more than 100 field runs to date for zonal isolation and treatment using this new technology (see Figure 1). It also examines in detail the following two case histories: Phillips Davis Lease Well #8 in Louisiana’s WebsterParishMarathon’s J. Kaye Field Well #3-33 in Oklahoma’s Grady County.
Development of a Power and Data Transmission Thermoplastic Composite Coiled Tubing for Electric Drilling
Authors: Kamp G. P. , Betts M. 
Published: December 2007

Abstract
Composite Coiled Tubing (CCT) is well on its way of becoming a widely accepted alternative to steel CT. Increased corrosion and fatigue resistance combined with a high strength to weight ratio are the main drivers behind these developments. Current CCT applications are limited to service strings and flowlines, however in 1997 Shell International Exploration and Production together with Airborne Development started the development of a thermoplastic composite coiled tubing for drilling purposes. To date, various prototypes have been manufactured and tested for internal pressure, tension, compression, bending, bending fatigue and chemical ageing.
Latest developments aim to embed electric power conductors within the wall thickness of the composite pipe that will enable the use of Electric Drilling Motors, Electric Submersible Pumps and electric tractors. In addition, real-time data transmission is possible by superimposing the data signal onto the power conduit. Such a Power & Data Transmission Composite Coiled Tubing (PDT-CCT) has better hydraulic performance than a CT with internal wireline, and is easier to use from an operational aspect. Coil materials used include advanced thermoplastic matrix materials, glass fibres for strength layers and electric insulation, and carbon fibres to provide strength, stiffness and electrical screening. Furthermore there is the possibility to embed optical fibres to measure temperature, flow and pressure along the complete string length and to monitor the condition of the composite material.
This coil avoids currently encountered problems with thermosetting CCT such as: Low working temperatures; temperatures in excess of 150°C will be possible with the PDT-CCTCollapse of thermoplastic liner; the PDT-CCT liner is welded to the structural layersUnexpected failure; monitoring strain and chemical ageing provides early warning for failureLow density; the copper conductors increase the coil density to avoid buoyancy induced bucklingLow stiffness; electric or hydraulic tractors along the string length enable Extended Reach CT Drilling
Composite Coiled Tubing Solution
Authors: Wheaton Terry R. , Berning Scott A. , Headrick Dick , Feechan Mike , Isennock Clint , Fowler Stewart H. 
Published: December 2007

Abstract
Depending on the application, composite coiled tubing (CCT) may serve as a cost-effective alternative to conventional coiled tubing.1
Gas wells in Alberta, Canada often lose production when hydrates form as a result of temperature drops in gas flow. To reduce gas-flow temperature drop and prevent hydrates from forming, operators commonly use a steel heater string to heat the annular area between the production tubing and casing. Some wells require more heat to reach the critical hydrate temperature depth than others, resulting in higher costs for heating and pumping equipment.
To reduce these costs, operators looked for a solution to temperature drop, and found it in CCT. Because of its low thermal conductivity (heat loss), a CCT heater string can reduce the need for upgrading or replacing surface heating and pumping equipment.
Measuring Safety and Environmental Performance in the U.S. Offshore Oil and Gas Industry
Authors: Beittel R. L. , Atkins S. R. 
Published: December 2007

Abstract
The U.S. Minerals Mangement Service (MMS), U.S. Coast Guard, and oil and gas interests that operate in the U.S. Outer Continental Shelf (OCS) cooperated to create four types of quantitative, normalized, historical indicators of the safety and environmental performance of offshore operations. The indicators cover employee injuries, oil spills, other incidents that could cause injuries or pollution, and noncompliances with safety and environmental regulations. The performance indicators are reported as OCS industry incident rates or participating company incident rates. Twenty specific incident rates are generated annually using arithmetic formulas that operate on performance data developed by MMS and the participating OCS operating companies. This paper explains the process used to develop the OCS performance measures, describes the OCS performance data, and presents the performance measures formulas. In addition, the industry and participating companies’ incident rates for 1996, 1997, and 1998 are reported and discussed.
Managing Stress: A Team Approach
Authors: Delaney Martin 
Published: December 2007

Abstract
There is growing evidence to suggest that stress is one of the most common factors contributing to work related ill health, sickness absence and lowered work performance.
Using material already developed within BP Amoco and with some external support, a number of interventions were developed to target specific aspects or work related stress. The interventions are delivered as separate workshop based packages. This paper will describe the development and use of these workshops and other resources.
Meeting the Challenges of New Environmental Regulations
Authors: Hassanali K. M. , Ramnath K. 
Published: December 2007

Abstract
The requirements of the Environmental Management Act of 1995 establish environmental regulations for industries in Trinidad and Tobago. Newly drafted rules and regulations soon to be presented to Parliament will place greater regulatory responsibilities on the energy industry in Trinidad and Tobago, in respect of compliance and its attendant cost.
The main environmental regulations and standards pertaining to the petroleum industry are:
Environmental Management Act (1995). Certificate of Environmental Clearance Rules (1999) (Draft). Environmentally Sensitive Areas Rules (1999) (Draft). Environmentally Sensitive Species Rules (1999) (Draft). Water Pollution Rules (1999) (Draft). Trinidad and Tobago National Environmental Policy. Specification for the effluent from industrial processes discharged into the Environment TTBS/EMA standard TTS 547:1998. Air Pollution (Stationary Sources) Rules.
The Petroleum Company of Trinidad and Tobago Limited (Petrotrin), has responded to this challenge by developing environmental management strategies as well as introducing new technologies in its operations, to reduce impacts on the environment. These strategies include:
Implementation of an ISO 14000 pilot project. Establishment of a ‘Quality Team’. Participation in the development of standards for liquid effluents and vehicle emissions. Training of management and supervisory staff. Monitoring of liquid effluents and air quality. Conducting environmental impact assessments. Conducting facility audits. Assessment of sensitive areas which the company operates within or in close proximity to. Development and implementation of waste management programmes.
The overall effect of these proactive programmes has improved Petrotrin's environmental performance and compliance.
Petrotrin's corporate commitment to excellence in the management of its environmental responsibilities is pervasive. As a leader in Trinidad and Tobago oil and gas industry, Petrotrin is ever mindful that every environmental event has an ultimate ecological consequence, regardless of its size, and that such a consequence could affect human health, animal and plant life. The overall effort has been worthwhile due to the enormous increase in the understanding of our environment and the improvements being achieved.
Hearing Conservation Program in the Upstream E&P Operations - A Case Study
Authors: Gourh Ramesh C. , Chakraborty Ashok B. 
Published: December 2007

Abstract
In the E & P operations, one of the critical area under the occupational health safety is the hearing conservation of employees. One of the main reason for the impairment of hearing is the excessive sound level commonly called "noise" in the work area. To undertake a comprehensive program on hearing conservation of employees, it is necessary to undertake surveillance of the area adopting different techniques along with proper study and to implement control actions, as necessary.
In this paper, the outcome of a study relating to the comprehensive noise exposure survey which was undertaken on two offshore platforms, one jack up rig recently, and few onland rigs earlier, have been covered along with the control measures which were found necessary. A review was made of 212 persons representing cross section of the work force. This group was studied for the audiometric performance changes over the period of their employment by comparing their recent audiogram with the first audiogram taken at the time of joining initially. At the same time the frequency spectrum of noise on the platforms and drilling rigs was studied and it was compared with the noise rating curve NR - 70. The hearing capacity of the work force was found to be within the normal range before work but after post work, there was marginal shift.
Based on the study on the noise level and the frequency characteristics, appropriate recommendations to the work situations were made for the noise control at the sources and also for minimizing the exposures levels. The other control measures included were the effective safety and environment management system, condition monitoring and technical audit besides a monitoring program. Basically, a 3C program called (collect - control - correct) was initiated along with imparting knowledge and to promote consciousness amongst employees about noise pollution, its effect on hearing, health and the preventive measures required to ensure safe and congenial work environment. This paper primarily relates to the sharing of experience in the area of occupational health safety.
EIA of Siri and South Arne -- the Two First Offshore EIAs in Denmark
Authors: Andersen H. V. , Stuer-Lauridsen F. , Kinn S. J. , Tüxen E. , Reed M. 
Published: December 2007

Abstract
Amerada Hess A/S and Statoil Efterforskning og Produktion A/S have published EIAs for the development and operation of the South Arne and the Siri fields, respectively. Both EIAs focused on planned and accidental emissions during development and operation. The major impacts identified were associated with potential accidental oil spills and affected seabirds and aquatic organisms. After public hearings supplementary studies were carried out.