bluuebunny/crossref_metadata_2025 huggingface dataset:
Management of a New Build Jack-Up for Drilling An HPHT Well
Authors: Mars Paul , Baranthol Christian , Carriay Jean , Cotterill M. D.
Published: December 2007

The successful commissioning, acceptance and performance of a large, harsh environment, highly automated new build jack-up rig to safely and successfully drill its first well (deviated HPHT) relies on the effective joint management by the Drilling Contractor and Operator. The key factors underlying this success are correct equipment, the application of established procedures and experienced well trained personnel. This paper presents how co-operative management between the Drilling Contractor and Operator successfully brought the new build jack-up West Epsilon through the initial commissioning and acceptance stage to successfully drill a deep, deviated HPHT Well.
Reducing the Risk of Stuck Pipe in The Netherlands
Authors: Hopkins C. J. , Leicksenring R. A.
Published: December 2007

Stuck Pipe in the drilling industry results in hundreds of millions of dollars wasted world-wide. After such costs in NAM escalated in 1992 and 1993 a team was set up to establish the causes and provide structural solutions to reduce the associated stuck pipe costs. Analysis of current and historical data was used together with the regular reporting of statistics to increase awareness within the drilling environment. Stuck Pipe Prevention courses were created for well site personnel. Current information used world-wide was evaluated and used where applicable. Early input into the design of each new well enables potential problems to be covered and solutions sought in a timely manner. Computer programs have been used to increase our understanding of rock failure and assist in optimising flow rates. This paper attempts to show the changes that NAM has made in the way we do business and the perceived benefits from so doing.
Case History of Floating Mud Cap Drilling Techniques—Ardalin Field, Timan Pechora Basin, Russia
Authors: Reyna Erick
Published: December 2007

Floating Mud Cap Drilling Techniques have been used in the drilling industry since the early part of the 20th century. Rotating Heads have made this practice almost obsolete, but the practice is still used in areas where carbonate reservoirs and other highly permeable reservoirs experience either partial or full loss of returns[1-2].

The objective carbonate interval in the Ardalin field often experiences full loss of returns that cannot be controlled by conventional western or Russian techniques. Field operations occur in an ecologically sensitive tundra environment, under arctic weather conditions, accessible by only helicopter in summer and snow road in winter. Rotating heads would have been costly and difficult to design for a Russian rig. Floating Mud Cap Drilling operations, though basically a simple procedure, required fore thought and planning in order to be successful under these conditions. This paper will present the thought processes and planning used to successfully drill through the objective interval with full loss of mud returns.
Hole Cleaning in Extended Reach Wells: Field Experience and Theoretical Analysis Using a Pseudo-Oil (Acetal) Based Mud
Authors: Gao Erhu , Young A. C.
Published: December 2007

To achieve adequate hole cleaning has been one of the greatest concerns in drilling extended reach wells. Effective hole cleaning is often difficult to obtain, especially when drilling reactive shale formations in large diameter holes. This paper presents both the field experience and theoretical analysis of the hole cleaning performance of a pseudo-oil (Acetal) based mud in drilling extended reach wells. Based on the analysis, a series of field guidelines for effective hole cleaning was developed and is also presented.
Safe Drilling of HP/HT Wells, The Role of the Thermal Regime in Loss and Gain Phenomenon
Authors: Maury Vincent , Idelovici J. L.
Published: December 2007

Drilling through the overburden of an HP-HT reservoir located in the Central Graben of the North Sea (5400m TVD; pore pressure 110.7 MPa; Temp. 190°C) led to slight but persistant unstable conditions when flow checking the well. Progressive increase of the mud weight proved inefficient to mitigate a permanent increase of bottomhole gas. After the mudweight increase, the well became more unstable (flowing) and it further degenerated to pressure build up at the surface when the well was shut in for a B.O.P. test. A total of 30 rig days were lost in recovering the well stability including setting of a contingency liner.

The paper briefly describes the main features of the reservoir and drilling parameters used for drilling the 22/30 c-10 well, the observations made during the incidents. It gives an analysis of these observations which led to the identification of the cause of the abnormal behaviour as a transient thermal regime of the well combined with the effects of the ECD and the progressive mud weight increase.

The thermal and pressure regimes of the well during drilling and mud circulation interruptions consist of alternate cooling and reheating, with simultaneous variations of pressure (from static mud weight to E.C.D). Borehole stress evaluation shows how the near wellbore fracture gradient can be exceeded, when cooling is combined with E.C.D., inducing small fractures. Closure of these fractures on reheating is responsible for transient pressure build up and back flow, which are not true kick indicators, but were considered as such before correct identification of the mechanism. When the static mud weight is increased to "in principle" counteract the phenomenon, the far field in situ fracture gradient is exceeded. Numerical modelisations were made to quantify the mechanism.

Understanding the basic cause of the loss and gain allows us to propose a means to counteract it: no mud weight increase, attention to mud properties, precaution in the use of the mud heat exchanger. These recommendations were followed on the next well and similar symptoms were encountered but much less pronounced and of no risks for the well. Rig time lost, well control operation, and contingency liner setting could be avoided.

The conditions particular to HP/HT wells play a major role in this phenomenon.
Determination of Hydrostatic Pressure and Dynamic ECD by Computer Models and Field Measurements on the Directional HPHT Well 22130C-13
Authors: Baranthol Christian , Alfenore Jacques , Cotterill M. D. , Poux-Guillaume Gregoire
Published: December 2007

The margin between fracture pressure and formation pressure while drilling the HPHT section on the deviated Well 22/30c- 13 was marginal. To successfully drill this section required an accurate knowledge of the Equivalent Mud Weight (hydrostatic pressure) and Equivalent Circulating Density. This paper presents how field measurements in conjunction with computer model predictions of hydrostatic pressure and ECD were made and applied to drilling the HPHT section. The technique proved valid for use in future HPHT wells. This paper also presents the effect of barite sag on hydrostatic pressure and ECD in a deviated HPHT well.
A Case For University Credits For Industry's In-House Continuing Education Programs
Authors: Carlile R.E.
Published: December 2007

THE MINERALS INDUSTRIES HAVE LONG RECOGNIZED THE TANGIBLE AND INTANGIBLE RETURNS FROM CONTINUING EDUCATION PROGRAMS FOR THEIR TECHNICAL, SCIENTIFIC AND ADMINISTRATIVE PROGRAMS FOR THEIR TECHNICAL, SCIENTIFIC AND ADMINISTRATIVE PERSONNEL, THESE PROGRAMS ORIGINATE FROM THE MUTUAL DESIRES PERSONNEL, THESE PROGRAMS ORIGINATE FROM THE MUTUAL DESIRES OF THE EMPLOYER TO UPGRADE THE PROFESSIONAL COMPETENCE OF THE EMPLOYEE AND THE EMPLOYEES CONCURRENT DESIRES TO KEEP ABREAST OF NEW DEVELOPMENTS TO REVIEW THE STATE OF THE ART OF SPECIALIZED SUBJECTS, AND TO BETTER QUALIFY HIMSELF TO COMPETE IN AN EVERY CHANGING TECHNOLOGY. IN-HOUSE TRAINING AND CONTINUING EDUCATION PROGRAMS TO PROVIDE SUCH REVIEW AND EDUCATION FOR THE EMPLOYEE ARE BECOMING A RECOGNIZED FUNCTION OF COMPANIES COMPRISING THIS INDUSTRY. THESE COMPANY-SPONSORED SEMINARS, WORK-SHOPS, AND TRAINING SESSIONS ARE AUGMENTED BY THE PERMITTED ATTENDANCE OF EMPLOYEES AT COMMERCIALLY AND UNIVERSITY-PRESENTED WORKSHOPS, AGAIN UNDER THE RECOGNITION OF THE DERIVED BENEFITS ACCRUING TO EMPLOYEE AND EMPLOYER AND A HIGHER LEVEL OF PERFORMANCE RESULTING.
Effective Relative Permeability in Scale-Up and Simulation
Authors: Saad Naji , Cullick A. S. , Honarpour M. M.
Published: December 2007

In modern reservoir characterization, detailed heterogeneous models of reservoir properties are routinely scaled-up for flow simulation. In addition to single-phase flow properties, two-phase flow properties, relative permeability and capillary pressure functions must also be scaled up. Here techniques for determination and assignment of effective relative permeability and capillary pressure on different scales of heterogeneities are presented and discussed. Many authors have considered scales of heterogeneities, their influence on fluid flow, and calculation of effective properties at a particular scale. In this paper, however, we present a unified approach to this problem; we consider effective relative permeability and capillary pressure on multiple scales of heterogeneities, and discuss a procedure for considering these heterogeneities at each level so that the overall influence is represented in the flow simulation model, results of which are used for economic decisions.

A simulation technique and an analytical method for calculation of effective relative permeability and capillary pressure are presented. Scale-up of relative permeabilities results in a set of effective relative permeability curves and an effective capillary pressure curve for each larger-scale simulation grid block.

We show how these relative permeabilities, and the corresponding effective capillary pressure curves, can be grouped together to yield a manageable number of effective relative permeability and capillary pressure curves for flow simulation. The application of these techniques is demonstrated through 2D and 3D scale-up and flow simulation examples.
Pulsed Neutron Capture Log Evaluation - Louisiana Gulf Coast
Authors: Stieber S.J.
Published: December 2007

Saturations initially computed from Pulsed Neutron Capture log response usually vary significantly from final or "refined" values. In many instances, considerable juggling of "fixed" parameters is necessary before reasonable saturations are derived. Slight variations in water salinity, shaliness, hydrocarbon or rock matrix capture cross sections can result in significant saturation uncertainties. This study primarily concerns a statistical study of log response opposite zones of known saturation conditions and formation water salinity. A technique to compensate for shaliness based on relative natural gamma ray deflection is developed. The average relationships presented represent a standard error for computed water saturations of ±15 saturation percent. Normalizing techniques utilizing one or more intervals in which saturation conditions are known can substantially reduce this error.

Introduction

Since the introduction of Pulsed Neutron Capture logging, over 130 Neutron Lifetime Logs (Dresser Atlas)1 and 30 Thermal Decay Time logs (Schlumberger)2 have been run in Shell's South Pass Block 24 and South Pass Block 27 Fields. In many cases, quantitative interpretation of the log is difficult primarily because of wide variations in computed matrix capture cross sections (Sma) lack of porosity control, uncertainty in hydrocarbon capture cross sections, and the inability to compensate for shaliness.

All of the major producing horizons in the two fields are broken sand-shale sequences, normally compacted, with sand quality primarily varying with the degree of silt and clay content. Since "trend" analyses and normalizing techniques have proven effective in handling uncertain petrophysical parameters for similar sedimentary sections, the techniques were applied to PNC log interpretation.

Before any shaliness correction based on relative gamma ray deflection can be developed, one of the following assumptions must be made:

Shale is interbedded or laminated with clean sand. Shale or clay is evently distributed within the sand matrix. A combination of the above.
Cyclic Steaming in Heavy Oil Diatomite
Authors: Kumar M. , Beatty F. D.
Published: December 2007

Chevron currently uses cyclic steaming as a recovery method to produce economically its heavy oil diatomite resource in the Cymric field, San Joaquin Valley, California. A highly instrumented, cyclically steaming well from this field was simulated in this study to delineate important production mechanisms, to optimize operations, and to improve reser­ voir management. The model was constrained, as much as possible, by the available measured data.

Results show that fluid flow from the well to the reservoir is primarily through the hydraulic fracture induced by the in­ jected steam. Parameters with unique importance to model­ modeling cyclic steaming in diatomites are: ( 1) induced fracture dimension (length and height), (2) matrix permeability, (3) oil/water capillary pressure, (4) grid size perpendicular to fracture face, and (5)producing bottomhole pressures. Additionally, parameters important for conventional steam injection processes, such as relative permeabilities and injected steam volume, quality, and rate, are important for diatomites also. Oil production rates and steam/oil ratios calculated by this model compare reasonably with field data.
Subsidence and Well Failure in the South Belridge Diatomite Field
Authors: De Rouffignac E. P. , Bondor P. L. , Karanikas J. M. , Hara S. K.
Published: December 2007

Withdrawal of fluids from shallow, thick and low strength rock can cause substantial reservoir compaction leading to surface subsidence and well failure. This is the case for the Diatomite reservoir, where over 10 ft of subsidence have occurred in some areas. Well failure rates have averaged over 3% per year, resulting in several million dollars per year in well replacement and repair costs in the South Belridge Diatomite alone. A program has been underway to address this issue, including experimental, modeling and field monitoring work. An updated elastoplastic rock law based on laboratory data has been generated which includes not only standard shear failure mechanisms but also irreversible pore collapse occurring at low effective stresses (< 150 psi). This law was incorporated into a commercial finite element geomechanics simulator. Since the late 1980s, a network of level survey monuments has been used to monitor subsidence at Belridge. Model predictions of subsidence in Section 33 compare very well with field measured data, which show that water injection reduces subsidence from 7-8 inches per year to 1-2 inches per year, but does not abate well failure.

The model has been used to infer potential well failure mechanisms resulting from fluid withdrawal policies and to estimate the impact of alternative operating policies for a 5/8-acre waterflood project; results show that aggressive operation of a newly completed producer can potentially damage a nearby well and that 1/1 producer/injector ratio results in significantly less subsidence and lower shear strains than a 3/1 ratio.
Improving Production in Steamed Wells With a Ring Seal Packer
Authors: Speirs A. B. , Webster K. D.
Published: December 2007

The Ring Seal Packer (RSP) is a newly patented1 tool used to help isolate depleted zones from producing well bores in thermally enhanced reservoirs. This paper presents the design of the RSP, deployment methods, and successful field production results.
An Overview of McKittrick Coiled Tubing Drilling Project
Authors: Ewert D. P. , Ramagno R. A. , Hurkmans R. S.
Published: December 2007

In an effort to reduce drilling costs on thermal wells, service companies began reducing casing sizes and well pad location sizes in 1993. Based on a successful four- well pilot project completed in early 1994 at the Belridge Field, a 115-well steam injector project was completed in the McKittrick Field in late 1994, of which 68 wells were drilled with coiled tubing.

This paper will discuss why slimhole completions and coiled tubing drilling were selected for this project, the operational aspects of drilling 68 wells in 92 working days, and conclusions about the project.
Reservoir Simulation Improves Implementation of Midway Sunset Steamflood
Authors: Ellison T. K. , Clayton C. A.
Published: December 2007

Thermal reservoir simulation was utilized to understand, make development recommendations, and project the performance of the Monarch C steamflood in a portion of Mobil’s South Midway Sunset field. The Monarch, a thick sequence of complex turbidite deposition, is characterized by extreme geological heterogeneity (lithofacies-controlled permeability and saturation variation, and mudstone barrier layers). Steamflood performance in the Monarch is related directly to the reservoir quality, and the path of steam flow is significantly influenced by the numerous laterally extensive mudstone barriers. The fine grain clay-bearing sediments were deposited on the anticline, distal from the source, whereas the coarser grain sediments, with little clay, were deposited on the more proximal syncline and steep dip areas. Consequently, steamflood performance improves relative to the crest since reservoir quality improves (including oil saturation), clay content decreases, and structure (dip) becomes more pronounced.

The simulation models were constructed to capture the heterogeneity. Two models were constructed, a single pattern model for a pattern with good performance, and a multi-pattern strip model that linked patterns of good performance with poorly performing patterns on the crest of the structure. Simulation results indicated the initial completion strategy, that ignored the mudstone barriers, often resulted in misalignment between injector and producer completions that severely limited performance. A complete overhaul of the well completions was required to improve die steamflood. Subsequent to the simulation work, the steamflood was re-engineered, based on intensive pattem-by-pattem and well-by-well reviews, to include producer recompletions and limited entry steam injectors. Steamflood performance improved following the redesign.
New Models for Natural and Hydraulic Fracturing of Heterogeneous Rock
Authors: Sahimi Muhammad
Published: December 2007

The development of fracture networks in heterogeneous rock during natural or hydraulic fracturing is studied using discrete network models of rock and Monte Carlo simulations. The models produce complex fractal networks of interconnected fractures whose structures depend on the spatial distribution of the heterogeneities of the rock. The resulting fracture patterns and their properties are shown to be in agreement with those of field-scale porous media. Thus, given the distribution of the heterogeneities of rock, one can simulate its fracturing process, and obtain an accurate map of its fracture network.
The Role of Latent Heat in Heat Management of Mature Steamfloods
Authors: Kimber K. D. , Emerson G. G. , Luce T. H. , Deemer A. R.
Published: December 2007

Proper heat management practices are critical to the economic success of many heavy oil steam floods. In relatively thick reservoirs such as those found in Kern River Field, California, strong steam override and gravity drainage of heated oil and water typify the after steam breakthrough stage of oil production. At this stage, many steam flood operators minimize operating costs by injecting only enough energy to maintain the growth of the steam chest and sustain the gravity drainage process. Injection rates and/or injected steam quality can be reduced to meet these reduced energy requirements. The form of the energy (i.e., steam vapor or hot water) dictates the efficiency by which oil is heated as well as the effectiveness of various mechanisms responsible for its production.

The economic value of various heat delivery strategies for mature steam floods was investigated. Recommendations are given as to whether the total heat or the latent heat injected is the controlling factor in meeting the minimum energy to be delivered for economically optimal oil recovery from mature steam floods. The contribution of sensible heat on oil recovery and its impact on the economics of mature steam floods is also discussed.
Kern River Revisited: Life After Steam Flood
Authors: Jones Jeff , McWilliams Michael , Sturm David
Published: December 2007

Santa Fe Energy Resources operated a fully developed, 2-1/2 acre, inverted 5-spot steam flood in the Kern River field in the lower Kern River series sand from1980 through 1986. Original reservoir depletion plans envisioned sequentially flooding shallower sand packages, however plans to redeploy the steamflood in the next interval have been postponed due to weak oil price. Since 1989, Santa Fe has been in an intensive cyclic steam development program including innovative facilities configurations and well work. The result is production equal to the peak rates observed during the steam flood with lower lifting costs.
Biological Treatment of Drilling Waste
Authors: PERIE F. H. , SERIS J. L. , MARTIGNON A. P.
Published: December 2007

Off shore operators are now faced with more stringent forthcoming regulations regarding waste discharge. Several aspects are to be taken into account when considering waste disposal in the sea; among them, the total amount of COD and the toxicity. While, in many regards, the problem caused by the processing fluids toxicity has been addressed, the elimination of residual COD from the waste is yet to be solved. Biodegradation of drilling waste is one of the major routes taken by third party contracters to address the reduction of COD in sea-discharged cuttings.

This report describes a technique specifically developed to enhance drilling waste biodegradation under selected conditions. The suggested treatment involved biological catalysts used in conjonction with or prior to the biodegradation. We demonstrated that the considered environment-compatible substitute for oil-based mud could be more efficently biodegraded if an enzymatic pretreatment was carried out prior to or during the actual biodegradation. The biodegradation rate, expressed as CO2 evolvement, was significantly higher in lipase-treated cultures. In addition, we demonstrated that this treatment was applicable to substrates in emulsion, suspension, or adsorbed on solid.
Proactive Participation in the Education Process
Authors: Ordway H. E.
Published: December 2007

Education of the younger generation as to the importance of energy and its recovery methods is essential to foster an informed public. Additionally, these educational programs help to generate interest in careers in scientific fields. The younger generation is the technical resource of the future energy business.

A quality approach to educating school children ages 5 through 12 about the everyday efforts people make to produce oil and natural gas in concert with the environment has been developed and evolved over the past years. The school presentation while designed for children includes discussions of environmental risk analysis as well as production and exploration techniques. The teaching aides include colorful graphics and an "environmentally aware" kit fox character named "Pockets", as well as local field examples and hands-on experiences. The program is most successful when developed for the regional geographic setting allowing children to relate to the examples, however, the teaching techniques developed through the experience can be adapted throughout the industry.
We've Got the Laws-What about the Communication?
Authors: Mollock G. N.
Published: December 2007

Each month, governmental and industry publications discuss proposed and newly enacted environmental legislation. At first glance, the most difficult aspects of new environmental regulations are to understand and implement the requirements. In reality, these are secondary, compared to assuring that our field employees "buy in" to the requirements. Experience has proven to me that our responsibility as environmental managers includes, not only understanding the requirements, but "selling" them to our field employees. That means explaining the rationale for the law and ultimately asking our field employees for the best way to implement performance related requirements. Our field employees have the "hands on" experience to solve problems using the wisdom gained from years of field work. Once they are involved in the process, accountability for the results demanded by government is more easily achieved. Here is an example of what I mean.

Texas Railroad Commission Rule 91 requires cleanup to 1% TPH within one year of an oil spill. Prior to Rule 91 becoming law, we explained the proposed requirements and their rationale to our Texas field employees. They assisted us with our comments on the proposal. When Rule 91 was enacted in November 1993, our field employees were already aware of the requirements and enthusiastic about trying various amendments to remediate oil spills. In other words, we had involved the people most closely affected by the law, in the legislative process.

Not all field employees have bought into this process, but more and more are coming on board every day. At times, we may become frustrated with the process, but the results are well worth the effort.
Economic Impact of Potential NORM Regulations
Authors: Smith G. E. , Fitzgibbon Timothy , Karp Steven
Published: December 2007

Oil and gas field wastes and sites contaminated with naturally occurring radioactive materials (NORM) have quickly become a focus of substantial attention by regulators both at the state and federal level. Although currently regulated in a number of states, the Environmental Protection Agency (EPA) has indicated a desire to develop federal regulations to address management and disposal of NORM-contaminated wastes.

This paper provides a brief overview of current state NORM regulations, currently available technologies for managing and disposing NORM wastes, and the cost of employing these techniques. Based on these characterizations and alternative assumptions about the volume of NORM wastes, four alternative scenarios have been developed to bracket potential future NORM requirements. These scenarios have been used as the basis for an analysis of the potential economic and supply impacts of NORM requirements on the U.S. oil and gas industry.

The results illustrate that a reasonable approach to regulation that focuses only on those NORM wastes that pose a risk and allows producers to use safe, low cost disposal methods (downhole or other) would have minimal economic impacts on the oil and gas industry. A very stringent regulatory approach that covered large volumes of wastes, required the use of higher cost disposal techniques, and required extensive site clean-up activities could have a substantial economic impact, resulting in a loss of up to 20 percent of U.S. oil production and 8 percent of U.S. gas production by 2000. The costs of compliance with these alternative approaches could range from $71 million to over $14 billion annually. Between these two cases lies the opportunity for regulators to develop requirements for management and disposal of NORM wastes that will address any environmental and human health risks posed at industry sites without imposing unnecessarily costly regulations on the U.S. oil and gas E&P industry.
Radiological Dose Assessment Related to Management of Naturally Occurring Radioactive Materials Generated by the Petroleum Industry
Authors: Smith K. P. , Blunt D. L. , Williams G. P. , Tebes C. L.
Published: December 2007

A preliminary radiological dose assessment related to equipment decontamination, subsurface disposal, landspreading, equipment smelting, and equipment burial was conducted to address concerns regarding the presence of naturally occurring radioactive materials in production waste streams. The assessment evaluated the relative dose of these activities and included a sensitivity analysis of certain input parameters. Future studies and potential policy actions are recommended.
Oil & Gas Exploration and Production Waste – RCRA Exemptions and Non-exempts
Authors: Dutta S. , Alam W.
Published: December 2007

Petroleum industry generates substantial amounts of wastes that is related to exploration, drilling, production, and development activities. Management of these wastes is essential to ensure protection of human health and the environment and also to comply with the regulations that govern them. These regulation were based mainly upon a study done by U.S. Environmental Protection Agency (EPA) on the impact of these wastes on environment while considering the economic impact of subjecting these wastes to the Resource Conservation and Recovery Act (RCRA), Subtitle C regulations.

Based on this study, exemption is granted to petroleum wastes that results from exploration, drilling, production, and development activities. Under this exemption petroleum wastes are not considered hazardous wastes. To address the diverse environmental and programmatic issues posed by these petroleum wastes, EPA has taken a three-pronged approach: (1) Improving Federal programs under authorities in Subtitle D of RCRA, the Clean Water Act (CWA), and the Safe Drinking Water Act (SDWA); (2) Working with States to encourage changes in their regulations and enforcement to improve some programs; and (3) Working with congress to develop any additional statutory authorities that may be required. Confusion about the exempt and non-exempt status of wastes from the exploration and production (E & P) activities in the petroleum industry seem to be quite prevalent, especially in light of the State and local requirements being different in many cases. This paper is an attempt to clarify the exempt and non-exempt status of wastes and to provide a clear understanding of the regulations that the industry must abide by in order to comply with both State and Federal requirements. Acceptable methods of waste handling and management are also discussed in this paper which should help the industry in pollution prevention and resource conservation aspect of waste management.
Removal and Treatment of Mercury Contamination at Gas Processing Facilities
Authors: Wilhelm S. Mark , McArthur Alan
Published: December 2007

Processing of gas containing mercury invariably leads to contamination of equipment and can generate waste in the form of sludge and spent adsorbent materials. Occasional accidents can also lead to soil contamination. This paper reviews mercury contamination in the gas processing industry and discusses newly developed methods for clean-up and disposal of mercury waste.

Research and development (sponsored by the Gas Research Institute) have produced new technology for mercury removal from complex matrices. Equipment decontamination is accomplished using chemical cleaning solutions that selectively oxidize and complex elemental mercury deposits. These cleaning formulations include aqueous base solutions containing iodine as the complexing agent and organic (alcohol) base solutions using complexing agents.

Soil, sludge, and debris must be thermally processed to remove (recycle) mercury. Thermal systems use vacuum, inert gas, or air as the carrier medium. If air is used, sulfur In the matrix Is converted to SO2 and hydrocarbons are oxidized as well, depending upon design. Anaerobic thermal systems employ selective condensation and/or adsorption to separate sulfur and hydrocarbons from mercury. Spent adsorbent materials are also thermally processed using strictly anaerobic conditions to avoid exothermal reactions involving carbon.

The regulatory climate relative to mercury is changing rapidly. Regulations covering treated debris and soils may require total mercury concentrations of less than 2 mg/kg for burial. Total mercury analysis rather than leaching procedure (TCLP) is becoming the norm in regulations and specifications. Sampling and analysis procedures for contaminated surfaces are under development.
Reducing Costs with a Corporate Waste Management Team
Authors: Redweik R. J.
Published: December 2007

In an attempt to minimize cost and potential future liability associated with hazardous waste disposal, a corporate Waste Site Management Team was established to review and approve all hazardous waste sites used by the corporation. Due to the ever changing legal and regulatory climate, the focus of the Team has evolved and broadened during the past decade. With a new name in 1993, the Waste Management Team expanded its focus to cover the management of all wastes being generated. Although the Team is still responsible for the review and approval of hazardous waste treatment, storage, and disposal (TSD) facilities, the focus is broadening to nonhazardous waste sites and recycling facilities. The mission of the Team is now to identify and maintain reliable waste management options, assist in the review and assessment of waste management alternatives that include source reduction and recycling, facilitate cross-functional cooperation between the Shell companies and divisions, and reduce the total cost of waste management for the corporation. A major source of cost savings has resulted from membership in an auditing cooperative and revisions to the site inspection frequency.
Health Risk Assessment for Radium Discharged Offshore in Produced Water
Authors: Meinhold A. F. , Holtzman S. , Hamilton L. D.
Published: December 2007

This paper reports on a probabilistic risk assessment of estimated incremental individual lifetime fatal cancer risks to recreational fishermen from radium in produced water discharged by offshore oil production platforms. A direct approach used limited measurements of radium concentrations in fishes caught near three shallow offshore platforms. A predictive modeling approach estimated the range of radium concentrations in fishes caught near deeper platforms. Estimated risks were described as probability distributions. Median predicted risks associated with shallow offshore platforms, representing worst-case conditions, were always less than 1 × l0−5. Median risks for platforms in deeper water were always less than 3 × 10−7.
Regional Assessment of Produced Water Treatment and Disposal Practices and Research Needs
Authors: Lawrence Alonzo Wm. , Miller Jeffrey A. , Miller Daniel L. , Hayes Thomas D.
Published: December 2007

Produced water accounts for greater than 80 percent by volume of the residual material generated in the natural gas industry. Cost-effective and environmentally acceptable disposal of these waters is critical to the continued economic production of natural gas. The Gas Research Institute (GRI) has recently completed a comprehensive assessment of the demographics of produced water characterized according to volumes and geographic location of the gas producing geologic provinces of the United States. This information in association with both the federal and state environmental regulations has been used to identify potential cost-effective produced water treatment research opportunities which are described in this paper.

The study involved the use of a computer-based engineering-economic model, Produced Water Management Options Model (PWMOM), which combines engineering process models with a cost performance data base to predict the economics of a spectrum of unit water treatment processes and treatment trains. Various produced water scenarios, i.e., volumes, qualities and regulatory requirements, were evaluated and categorized to focus on the natural gas producing regions of the U.S. where produced waters could be surface discharged under the National Pollutant Discharge Elimination System (NPDES). Residual brines from produced water treatment would continue to be injected. Unit process technologies evaluated include deoiling (removal of free oil & grease), iron removal, dissolved organic removal (soluble organic treatment) and partial demineralization. Federal and state regulations were reviewed to identify where surface discharge could be or has been practiced to determine where cost-effective treatment could increase the opportunity for non-injection disposal alternatives.

To complete this analysis, surface treatment costs were generated with PWMOM and compared to deep well injection costs. Costs for deep well injection were generated using Salt Water Injection Model (SWIM), a model developed by GRI earlier in this research project. Promising technologies that have been identified include aerobic biological oxidation using fluidized beds, partial demineralization using electrodialysis and reverse osmosis, and a natural freeze-thaw evaporation process for cold climates. Laboratory and pilot studies that have been initiated to evaluate these processes are described here. Additional surface water discharge opportunities may exist where beneficial use such as irrigation or watering livestock is possible and where treatment will ensure that the release to surface waters will not violate water quality standards.
The EPA Risk Management Program Regulations and Their Applicability to Oil and Gas Operations
Authors: Freedman Edward L.
Published: December 2007

Oil and gas operations will be impacted by the risk management program regulations to be promulgated by the U.S. Environmental Protection Agency (EPA) under the Clean Air Act, as amended in 1990 (CAA). In part, the CAA requires facilities with certain hazardous substances above threshold quantities to conduct hazard assessments, implement accident prevention and emergency response programs and prepare risk management plans. The EPA has published final lists of toxic and flammable substances; hydrogen sulfide and several hydrocarbons were listed. The risk management program regulations have been proposed.

This paper provides an overview of the statutory requirements for accidental release prevention in section 112(r) of the CAA. The applicability of the final lists to the oil and gas industry is described and the proposed risk management program regulations are summarized. Examples of analyses illustrating potential effects of accidental releases of "sour" gas, methane, propane and pentane are presented. The paper concludes with a brief discussion of some major issues raised in public comments to the proposed rule.
Oilfield Pollution: Can There Be Settlement Without Remediation
Authors: Spiegelberg Frank D.
Published: December 2007

In 1964, an oil well blew out. Over the years, oil continued to seep from the location. Suit was filed in 1985 for $31 Million for loss of value of the land, costs of remediation and costs to plug the well properly. An action was also filed in the state conservation commission by the operator. In 1987, the trial court held that the operator owed $4.512 Million in damages including $2.1 Million for proper plugging of the well and another $2.1 Million for remediation costs. Also in 1987, the state conservation commission ruled that the well was properly plugged and abandoned and ordered the operator to complete an approved remediation plan. The case was appealed and was eventually settled after rulings by the state Court of Appeals and Supreme Court.

This paper discusses: (1) case study of the above facts and circumstances and the resulting inconsistencies between the administrative agency rulings and the civil court's rulings and how they affect remediation as well as settlement of claims; (2) another case study where a court ruled that regard-less of a settlement that included the payment of remediation costs to the surface owner, the operator was primarily liable for clean-up costs to the administrative agency and the operator's bond was forfeited to cover the costs of clean-up; (3) the most recent state Supreme Court ruling to affect this issue; (4) the legal ramifications of settlement without remediation of an oil field pollution site.
A Cost-Effective Statistical Screening Method to Detect Oilfield Brine Contamination
Authors: Alyanak Nancy , Grace James T. , Campbell Michael D.
Published: December 2007

A statistical screening method has been developed using Tolerance Limits for barium (Ba+2) to identify contamination of a fresh-water aquifer by oilfield brines. The method requires an understanding of the local hydrochemistry of oilfield brines, inexpensive, publicly available hydrochemical data, a single sample analysis from the suspect well and the application of a simple statistical procedure. While this method may not provide absolute evidence of oilfield brine contamination of a fresh-water aquifer, it does identify conditions where brine contamination is a strong probability over other possible sources of chlorides.
A Cost Effective Bioremediation Strategy Using Low Technology Resources For Reclamation Of Dry Land Hydrocarbon Contamination: A Case Study
Authors: Robb A. J. , Hoggatt P. R.
Published: December 2007

Hydrocarbon containing soil was bioremediated at a combination wastewater and slop oil skim evaporation pond utilizing cost effective low technology resources. Fluids and sludge from the football field-sized pond were extraction procedure toxicity and purgeable organics tested, and total petroleum hydrocarbon (TPH) concentrations determined. An impact risk analysis was performed, and a corrective action plan developed and implemented. The three year project was closely coordinated with the Kansas Corporation Commission (KCC) and the Kansas Department of Health and Environment (KDHE) who established the closure level. The impacted soils at the pond were completely excavated and closure was immediately granted by KDHE for the excavated area. The 24,000 cubic yards of excavated soil were then surface spread on adjacent Mobil property. A nutrient and microbial base was applied to bioaugment the soil. The preapplication land surface and the subsequently land farmed soil was periodically disced and chiseled.

A job safety plan including industrial hygiene measures to eliminate workforce exposure was developed and implemented. The final remediation cost analysis amounts to $1.48 per cubic yard compared to the $30 to $150 per cubic yard industry estimates for similar projects. Several factors were critical in allowing costs to remain so low: 1) assessment and implementation by local in-house staff; 2) conservative remedial action plan and sampling strategy; 3) local contractors; 4) locally available soil amendment; and 5) effective regulatory coordination. The methods described can be used to cost effectively characterize and bioremediate other sites where hydrocarbon-impacted soils exist in similar dry-land environments.
Soil Gas Surveys: A Cost-Effective Site Assessment Technique
Authors: Barker G. W. , Brown D. R. , Corgan J. M. , Fisher J. B. , Raterman K. T. , Trent G. L.
Published: December 2007

Accurate delineation of the extent of subsurface hydrocarbon contamination in soils and ground water is important when initiating a monitoring plan or considering remediation options at E&P sites. Traditional site-assessment techniques used to delineate subsurface hydrocarbon contaminants (e.g., soil boreholes, excavation, monitor well installation, etc.) can be expensive, time-consuming, and disruptive to local land use or production operations. Soil gas surveys can provide a rapid, cost-effective, nonobtrusive alternative to traditional site-assessment techniques.
A Protocol for Assessing the Biotreatability of Hydrocarbon Contaminated Exploration and Production Site Soils
Authors: Tezak James , Miller Jeffrey A. , Lawrence Alonzo Wm. , Keffer Ronald E. , Weightman Robin , Hayes Thomas D.
Published: December 2007

It is estimated that there are over 260,000 natural gas production wells in the continental United States. At many of these locations, production or reserve pits exist which may require remediation depending on several conditions such as: the manner in which they were initially closed; whether or not they were lined; and the local climate, soil type, and depth to groundwater.

As part of the Gas Research Institute (GRI) research program on exploration and production (E&P) site remediation, a treatability protocol is being developed to facilitate the rapid assessment of the amenability of the contaminated soils to remediation by biological processes. This paper describes the treatability protocol and the results of a series of treatability tests on a spectrum of hydrocarbon contaminated E&P soils collected from various operating locations throughout the United States.

The soils are subjected to physical and chemical characterization prior to treatability testing. Potential biotoxic characteristics of the soils are determined by a respirometry screening technique. Presuming that the soils are not toxic to aerobic soil microorganisms, 20 percent by weight aqueous slurries of the soils are prepared and subjected to continuous batch aeration for a six week period. Conditions favorable to microbial growth are maintained in the reactors by monitoring and augmentation as needed of pH, microbial nutrients and oxygen for microbial respiration. The extent of microbial degradation of the contaminant hydrocarbons is monitored by periodic measurement of total petroleum hydrocarbons (TPH), oil and grease, and individual hydrocarbon compounds as determined by gas chromatography. Microbial plate counts are prepared to document the biological viability of the treatment process.

This paper includes the treatability results obtained from subjecting a number of E&P pit soils to the treatability protocol. The factors influencing the amenability of these soils to bioremediation as determined from the test results are discussed.
The Evaluation Of Surface-Active Agents For Use In The Prevention Of Differential-Pressure Sticking Of Drill Pipe
Authors: Albers Daniel C. , Wieland Denton R.
Published: December 2007

In recent years differential-pressure sticking of drill pipe has become a very serious problem in the drilling industry. Surface-active agents are being used to a certain extent to aid in the elimination of this problem. In order to obtain a better understanding of the effect of surfactants, a laboratory investigation was performed to evaluate the efficiency of twenty various surfactant agents as to their ability to release differential-pressure stuck pipe. The surfactants tested included cationic, nonionic, ionic, and blended agents.

A number of surface-active agents were found to have very favorable properties for use in this type of pipe-sticking problem. Results indicated that the proper use of surface-active agents in the drilling fluid and spotting oil would definitely aid in the prevention and release of differential-pressure stuck pipe.

Introduction

Drill stem differential-pressure sticking is the result of drill collars laying against the mud filter cake on the wall of the drilled hole where the existing pressure differential acting against the isolated area of the drill collars in contact with the mud cake and the friction between the pipe and the cake are too large for a direct pull to effect a release. The problem of stuck drill pipe increases as deeper wells are drilled. This is due to the use of longer lengths of drill collars, oversize drill collars, high density drilling fluids, and abnormal formation pressures which are sometimes encountered A highly permeable low-pressure zone is more susceptible for this type of phenomenon due to the mud cake deposition and pressure differential being greater in these areas.

Normally, the hydrostatic pressure exerted by the drilling fluid column is uniformly distributed over the entire surface area of the drill pipe. Any restriction of uniform pressure distribution, such as that caused when the drill pipe movement ceases and the drill collars rest against the wall, creates an unbalanced hydrostatic pressure or a pressure differential, which results in a force that retains the collars against the wall of the hole and restricts pipe movement.