bluuebunny/crossref_metadata_2025_split huggingface dataset:
Sweetening of Sour Crude Using Gas Stripping Process
Authors: Clanton G.W. , Gipson R.E. 
Published: December 2007

Abstract
A reduction of the hydrogen sulfide content of crude oil can be accomplished by stripping with gas in a contact tower at low pressures. In addition, stabilization of the oil or condensate is accomplished simultaneously with less shrinkage and tank losses as compared with multi-stage separation.
Several simplified processes can be utilized to accomplish the desired results and are discussed in the paper. A computer program is available which will simplify the tray-by-tray equilibrium calculations for design purposes. The process can be adapted to purposes. The process can be adapted to both small and large installations and sulfur recovery from the sour overhead vapor may be added to the larger installations in order to accomplish a shorter payout. Also some form of hydrocarbon recovery from the stripping and flash gas would be desirable in areas where gas liquids have any value.
Design and installation of a unit was made which reduces the sulfur content from 500 ppm to less than 30 ppm using sweet natural gas for stripping and at the same time reduces the vapor pressure to less than 15 psia @ 100 degrees F to prevent vaporization losses during transportation in warm ocean waters. The processes shown herein afford a method whereby the H2S content of sour crude oil or condensate can be reduced at the production site. This helps to produce production site. This helps to produce a more valuable product and prevent pollution problems before they occur pollution problems before they occur in the more populated refinery area.
Introduction
Sweetening of sour crudes has recently become more important with the advent of new pollution control regulations and increased refinery treating costs. The stripping process utilizes Henry's law which states that the amount of a slightly soluble gas that dissolves in a liquid at a given temperature is very nearly proportional to the amount of the particular gas in the surrounding atmosphere.
Rapid Characterization of PAH's in Oils and Soils by Total Scanning Fluorescence
Authors: Gray N. R. , McMillen S. J. , Requejo A. G. , Kerr J. M. , Denoux Guy , McDonald T. J. 
Published: December 2007

ABSTRACT
Total Scanning Fluorescence (TSF) is a rapid and inexpensive technique that can be used for the analysis of polynuclear aromatic hydrocarbons (PAH's). The basis for the use of fluorescence is that, in general, emission/excitation wavelength maxima increase with increasing number of aromatic rings. The output of the TSF analysis is a fluorescence "fingerprint" consisting of a 3-D emission/excitation intensity contour diagram. This "fingerprint" can provide information about the content and relative composition of PAH's in samples.
To date, this technique has been applied primarily to the analysis of sediment samples collected as part of offshore geochemical exploration programs. In this study, TSF has been evaluated for the rapid screening of oils and soil extracts containing biodegraded crude oil. Analysis of ten crude oils from the southern and western regions of the U.S. shows that their fluorescence characteristics vary widely. These differences can be directly related to varying PAH composition. TSF "fingerprints" of oil subjected to bioremediation for 52 weeks show systematic differences from those of the unaltered oils. These differences suggest that TSF can be used to measure the abundance and composition of PAH's in samples and to detect loss of PAH's in samples that have undergone biodegradation.
The Effect of pH on Microbial Degradation of Oil-Based Drilling Mud in a Slurry-Phase Bioreactor
Authors: Crews Bonny , Malachosky Edward , Hinman L. D. 
Published: December 2007

ABSTRACT
A slurry phase bioreactor was used to degrade the hydrocarbon component of oil-based drilling mud residues to an acceptable level for land disposal. The initial oil and grease concentration in the residue was approximately 26% by weight. Laboratory treatability studies had indicated a potential for biological degradation of the material. Initial target levels of nutrients were set at 200 ppm P as phosphoric acid, and 500 ppm N as ammonium nitrate. Daily samples were taken from the bioreactor to monitor pH and microbiological activity (as oxygen uptake rate, OUR). Samples were analyzed weekly for oil and grease content, cations and anions, and phosphate, ammonia, and nitrate levels.
Despite adequate nutrient additions, sufficient aeration, and a pH within physiological range, the OUR rarely indicated bacterial activity sufficient to degrade the oily waste. The full-scale bioreactor behavior was contrary to that of bench-scale reactors used in the treatability studies. Several parameters which were investigated as potential causes of the variations in activity included aeration (as dissolved oxygen, DO), mixing, pH, and nitrogen-phosphorous ratio (N:P). The calcareous calcium chloride-based drilling waste was found to reduce the bioavailable phosphate, and resulted in low levels of soluble phosphate and a subsequent high N:P.
The pH of the system was lowered to 6.0-6.3 by phosphoric acid addition to increase phosphate availability. This resulted in a dramatic increase in the OUR (from ≤ 0.1 mg O2 L−1min−1 to 0.5 mg O2 L−1 min−1) and a subsequent downward trend of the total oil and grease in the slurry prior to the dismantling of the bioreactor and land disposal of the waste.
Synthetic-Based Mud Systems Offer Environmental Benefits Over Traditional Mud Systems
Authors: Candler J. E. , Rushing J. H. , Leuterman A. J. J. 
Published: December 2007

ABSTRACT
This paper addresses critical issues concerning the regulation of synthetic-based fluids in Outer Continental Shelf waters. Synthetic-based muds were not envisioned when discharge criteria were formulated a decade ago. It is critical that the U.S. Environmental Protection Agency investigate this new category, since the original permit language and discharge criteria may inhibit the utilization of this new technology and prevent the realization of volume reduction that can be achieved using synthetic-based muds.
To date, the EPA has not addressed the use of inhibitive mud systems as a control technology for reducing the quantity of pollutants. Drilling through shale formations is an integral part of drilling wells in the Gulf of Mexico. Solving problems associated with these formations can benefit the EPA, industry, and the environment.
The use of synthetic-based muds offers greater waste reducing capabilities than water-based muds. They also permit drilling in areas which now require oil-based mud to combat troublesome shales. Compared to hauling oil-based mud, synthetic-based muds offer significant non-water quality advantages in the areas of air pollution, worker safety, reduction of potential spills, and reduction in landfill usage.
Construction and Operation of a Biological Treatment Cell for the Treatment of Hydrocarbon-Contaminated Soil in Alaska
Authors: Ratliff M. D. 
Published: December 2007

ABSTRACT
The paper is a case study of a successful biological remediation cell (biocell) that was constructed and is being used in Kenai, Alaska. The cell was constructed to remediate petroleum hydrocarbon-contaminated soil. Biological remediation is a promising technology that can prove both environmentally friendly and cost effective in the treatment of petroleum hydrocarbon-contaminated soil. A biocell can be easy to construct and operate. The biocell utilized an enclosed treatment area and a sprinkler system to saturate the contaminated soil. The excess water was drained to a sump where it was pumped to holding tanks and profiled. Any nutrients or adjustments necessary to promote rapid biological growth and degradation were noted and performed. The project has proven to be successful and beneficial to the overall remediation project which was undertaken.
Resolving the Toxic Discharge Problems of the Sussex Field, Wyoming
Authors: Brus K. R. 
Published: December 2007

ABSTRACT
In many locations in the Rocky Mountains, water associated with oil production is very fresh (less than 5000 mg/1 Total Dissolved Solids (TDS)). Many operators in Wyoming discharge excess produced water to the surface, where it is depended upon by local livestock and wildlife. Much of Wyoming is semi-arid high plains, where the evaporation rate is 4 to 5 times the yearly precipitation total, so water is a precious commodity. When the EPA issued the Clean Water Act and the National Pollutant Discharge Elimination System (NPDES) in the 1970's, regulations were imposed affecting the quality of produced water discharges, restricting the TDS, specific chemical constituent concentrations and the dissolved oil and grease concentration. Operators must comply to the restrictions or face fines and eventual cancellation of the permit.
In 1988, the State of Wyoming issued a toxicity reduction regulation that required compliance by year's end 1992, to comply with national EPA requirements. Produced water that is discharged to streams has to fulfill whole-effluent Acute Toxicity testing protocol, in which immature fathead minnows and water fleas are exposed to the discharge fluid. If the water fails this testing, the toxicity has to be removed or reduced or the discharge discontinued. Many locations cannot economically tolerate the expense of some of the options for compliance, which could include sub-surface disposal. Furthermore, if all the water is injected, many streams will be dry most of the year, and the livestock and wildlife would suffer.
This presentation will recount the procedure that Conoco used to resolve the toxicity problem at the Sussex Field discharge. The process included 1) selection of toxicity reduction over sub-surface discharge, including economic considerations, 2) an attempt to identify the toxic components of the discharge, 3) selection of a toxicity remediation process, 4) design of a workable treatment facility and 5) installation and operation, at comparatively low capital expense, of a workable system.
An Evaluation of Produced Water Management Options in the Natural Gas Production Industry
Authors: Lawrence A. W. , Miller J. A. , Miller D. L. , Linz D. G. 
Published: December 2007

ABSTRACT
Potential environmental impacts of natural gas production have become the focus of increased regulatory activity in recent years. Because produced water accounts for greater than 80 percent by volume of the residual materials generated in the production of natural gas, cost-effective and environmentally acceptable disposal of these waters is critical to the continued economic production of natural gas. This Gas Research Institute (GRI) sponsored study is evaluating the technical and economic feasibility of a spectrum of produced water treatment and disposal options using an engineering economic management model developed by the study team.
This paper describes the model which was developed in a PC-based, linked spreadsheet format to allow the user to interactively evaluate alternative scenarios for treatment and disposal of a specific produced water with a stated volumetric production rate and water quality. The model contains twelve treatment process modules ranging from gravity settling to thermo-mechanical evaporation. Final disposal modules include: surface discharge; reinjection via Class II Injection Well; evaporation; and reuse. Modules for water transportation from well head to treatment site are included. Each process module contains a performance-cost relationship to facilitate computation of capital and operating cost for a given produced water management scenario.
The model is used to compute unit costs for produced water treatment and disposal according to a number of possible management scenarios ranging from discharge to surface waters to reinjection via Class II Injection Well. These computed costs are then compared to published costs for several existing produced water disposal operations. Modifications of the model to specifically address the management of produced water from offshore gas production activities are described.
The model developed in this study may be useful to natural gas producers both as an initial screening tool for evaluating produced water management options in the development of a new gas field and also in the consideration of the economically feasible responses to increased regulatory requirements. In addition, the model is being used by GRI to assist in delineating productive areas for research on produced water treatment which have the potential for reducing the future cost of disposal.
On-Site Monitoring of Drilling Fluids Toxicity
Authors: Hoskin S. J. , Strohl A. W. 
Published: December 2007

ABSTRACT
On-site monitoring of drilling fluids toxicity can play an important role in decisions concerning offshore drilling fluids discharges and engineering.
Two on-site methods of monitoring the toxicity of offshore drilling fluids discharges are (1) mathematical models that predict mysid LC50 values based on mud additive concentrations and (2) the Microtox® toxicity analyzer. This study introduces a new Microtox technique which allows contact of the test organism with the entire solid phase of the drilling fluid.
Laboratory and field drilling fluids are evaluated using this new technique. Results are correlated with mysid toxicity tests and traditional Microtox tests and compared with a mathematical model. The result is a valuable system for on-site compliance monitoring of drilling fluids toxicity.
Advances in Water Clarifier Chemistry for Treatment of Produced Water on Gulf of Mexico and North Sea Offshore Production Facilities
Authors: Durham D. K. 
Published: December 2007

ABSTRACT
Since 1987 EPA regulations applying to produced water discharge in the Gulf of Mexico have become increasingly stringent and have made it increasingly difficult for many platforms to remain in compliance with respect to oil content in the overboard produced water. In the North Sea a similar situation exists with respect to oil content specifications on discharged produced water set by regulatory agencies in the various North Sea sectors.
Because of this situation an intensive product development program was initiated to develop new water clarifiers that would allow the existing offshore water treating systems in the Gulf of Mexico and North Sea to treat the overboard water to meet the new stricter specifications pertaining to the overboard discharge of produced water.
This paper discusses the development of these new dithiocarbamate (DTC) based water clarifiers which effectively reduce insoluble hydrocarbon in offshore water treating systems where other conventional and first generation dithiocarbamate water clarifiers have been found to be ineffective, create unmanageable side effects, or are less cost effective.
Product selection and application techniques for these new dithiocarbamate water clarifiers and conventional water clarifiers are also discussed along with observations concerning the advantages and disadvantages of various types of offshore water treatment systems and equipment.
Environmental Considerations in Production Chemical Usage
Authors: Caudle D. D. , Bansal K. M. 
Published: December 2007

Abstract
Oilfield chemicals are primarily used to make crude saleable, to minimize process problems, and to treat produced water to meet regulatory guidelines for disposal into the sea (offshore) or injection underground (onshore). Where these chemicals end up depends on such factors as the nature of the chemicals, injection location, solubility, and distribution coefficient of the chemicals in the oil and water phases. Chemicals that end up in the water phase will get into the environment only if the water is discharged to the environment.
This paper examines a number of issues which impact the amount of chemical used and the limits on the minimization of its use. These issues include: attitudes towards chemical usage, process limitations, and physical/chemical behavior of the chemicals, and interactions with other chemicals in the system.
Wastes from the production treating chemicals are also discussed in this paper. A total system approach is proposed to minimize the chemical usage in production operations.
"Dry" Drilling Location—An Ultimate Source Reduction Challenge: Theory, Design, and Economics
Authors: Wojtanowicz A. K. 
Published: December 2007

ABSTRACT
The term "dry" wellsite denotes a drilling operation without the use of an earthen reserve mud pit in land drilling, or without the overboard dumping of bulk drilling fluid in offshore drilling. As the two field practices have been increasingly scrutinized in environmentally sensitive areas, and the hauling off of bulk waste drilling mud is either too expensive or impossible to do, the minimum-volume control (source reduction) becomes an important part of drilling technology. This paper presents mechanistic and economic models of the controlled-volume drilling process and their theoretical use to design a "dry" location.
The mechanistic model quantifies all phenomena and operations related to drilling fluid as they affect the volume of waste mud and cuttings discharged from a wellsite. The model simulates the treatment of drilling process discontinuities (non-drilling operations) when rapid volumetric changes occur. Also presented is the steady-state model of "drilling ahead" operations with active mechanisms for drilling mud dilution, separation of cuttings, dewatering, and recycling.
The economic model involves a breakeven analysis of all components of the mud management process (i.e. mud making, maintenance, processing, and disposal) together with temporary storage requirements. A computer program simulating drilling and mud management processes relates drilling technology, field practices, local geology, and regulatory constraints to the volumes of active, stored, and waste mud and the costs of mud making, maintenance, and disposal. Investigated in the computer simulation study are volumetric effects of various parameters such as drilling conditions, dewatering unit performance, and solids control efficiency. The study shows that drilling can be designed and conducted in such a way that the wellsite discharge will be minimal.
Also presented is an example design of a dry drilling location where the cost of source separation technology (dewatering) is fully offset by the savings in disposal and mud costs. The study demonstrates that dry drilling locations are technically feasible and economically sound when designed using principles of volumetric control of the drilling mud. Also discussed is a mathematical model and design methodology for well-planning considerations.
Post-Fracture Production Performance and Waterflood Management at Prudhoe Bay
Authors: Schuldt D. M. , Suttles D. J. , Martins J. P. , Breit V. S. 
Published: December 2007

Abstract
An aggressive hydraulic fracturing campaign, involving over 360 wells, has been conducted at Prudhoe Bay, primarily within the waterflood region of the field. High declines in gross fluid production rates (oil plus water) were observed in the first few months after the fracture stimulations were performed. Work was initiated to determine the cause of these declines and to identify any actions which would mitigate them.
A combination of diagnostic well work, field data analysis and reservoir studies to investigate the decline mechanisms are presented. The paper highlights the use of numerical simulation for investigating the reservoir mechanisms of decline, and the benefits associated with alternative waterflood management schemes.
Estimation of the Pseudoskin Factor Caused by a Restricted-Entry Well Under Multiphase Flow Conditions
Authors: Roadifer R. D. , Reynolds A. C. 
Published: December 2007

ABSTRACT
This work considers the analysis of pressure transient data obtained from a restricted-entry well under multiphase flow conditions. In particular, we examine the pseudoskin factor caused by partial penetration in a reservoir with multiple flowing phases.
Only the total skin factor, which is a linear combination of the mechanical skin factor due to damage or stimulation and the pseudoskin factor due to partial penetration, can be obtained directly from semilog analysis of pseudoradial flow pressure data. In order to obtain the true mechanical skin factor, an independent estimate of the pseudoskin factor due to to restricted entry is required.
The pseudoskin factor correlations of Yeh and Reynolds1 and Ding and Reynolds2 for a restricted-entry well completed in a multilayer reservoir are extended to obtain a new correlation for computation of the pseudoskin factor caused by a restricted-entry well in a reservoir with multiple flowing phases. An extensive set of two-phase (oil-water, gas-water, oil-gas) and three-phase (oil-gas-water) examples are presented and indicate this correlation yields accurate estimates of the pseudoskin factor.
Because this correlation is dependent upon the analysis of pressure transient data obtained under multiphase flow conditions, conditions under which such analysis can be performed and procedures for that analysis are discussed. A new semi-theoretical procedure for analyzing solution-gas systems in which free gas is produced at the sandface is presented. Numerical results for all of the multiphase systems considered in this study indicate that the common practice of approximating a gas cap or aquifer as a constant pressure boundary cannot be justified.
Improved Modeling of Oil/Water Flow in Naturally Fractured Reservoirs Using Effective Fracture Relative Permeabilities
Authors: Babadagli Tayfun , Ershaghi Iraj 
Published: December 2007

Abstract
Pseudo relative permeability curves have been used to model heterogeneous (layered) reservoirs in the past. Although the two-phase flow and the nature of heterogeneity are different from the layered systems, the same concept can be applied to the modeling of naturally fractured reservoirs. The proposed relative permeabilities are shown to be not only a function of saturation values but are also dependent on flow velocity, permeability and capillary pressure levels of the matrix.
The EFRP’s (Effective Fracture Relative Permeability) were generated for different rates and matrix properties in oil water systems. Using the EFRP curves, a dual porosity system can be reduced to a fracture network model. This provides a significant reduction and modification in modeling of dual porosity systems.
This type of modeling approach will reduce the time spent for matrix and transfer flow calculations and more emphasis can be devoted to represent the irregularity of the fracture pattern.