Ali

Welcome to the first issue of 2006! This issue marks a beginning and end for some things related to our journal: the name of our journal has changed to SPE Production & Operations; Wolfgang Deeg and Simon Richards have completed their terms as Review Chairpersons; and Richards has accepted the responsibility to act as Executive Editor for the new electronic journal, SPE Projects, Facilities & Construction. I want to thank both of them for their dedicated service to SPE and the assistance they have provided me over the last year.

As Deeg and Richards step down, new Review Chairpersons have already been appointed: Harold Brannon, Dean Wehunt, and Ali Ghalambor have all agreed to serve. Brannon is employed by BJ Services Co. in Houston; Wehunt is employed by Chevron Energy Technology Co. in Houston; and Ghalambor is located in Lafayette and is the Chairperson of the Petroleum Engineering Dept. at the U. of Louisiana at Lafayette. They join Ian Collins, Elise Striz, and Bill Bailey. I want to thank all of you for your willingness to serve SPE in this important function of Review Chairperson, and I look forward to working with you over the next year as we all strive to publish this esteemed technical journal.

Before introducing the papers in this issue, I would like to take a brief look back at our milestones for 2005. Last year, we significantly improved the time it takes to publish a paper in SPEPO. In my experience, the time for review depends on many factors, but the two main factors are the Technical Editors’ review time and the time taken by authors to make the required revisions. We have control over only the first factor and are working hard to address it. We added two new Review Chairpersons and substantially increased the number of Technical Editors. It is hoped that these changes will further reduce the cycle time.

Last year, we received a total of 374 papers; of those, four papers were accepted without revision, 61 papers were accepted with minor revision, 63 papers required major revision, 75 papers were declined after review, and 114 papers were initially declined for a variety of reasons. The remaining 51 papers are still under review. We published 36 papers in 2005 and have 26 papers awaiting publication in 2006. To eliminate this backlog, SPE decided to increase the number of papers from nine to 18 in this issue and up to 19 in the forthcoming May 2006 issue.

Before I move on to the papers, I would like to thank the SPE staff, particularly Stacie Hughes, Carole Young, Shashana Pearson-Hormillosa, and Holly Hargadine for their unconditional support during 2005.

Leading off this expanded issue, a scale management paper, Evaluation Methods for Suspended Solids and Produced Water as an Aid in Determining Effectiveness of Scale Control Both Downhole and Topside, outlines a method involving the evaluation of suspended solids in terms of amount, mineral type, composition, and texture along with brine chemistry that can greatly improve our understanding of the location of scale formation within production environment. Implementation of this analytical strategy can greatly improve scale management in terms of evaluating scale-squeeze placement effectiveness, squeeze lifetime, and topside scale-control challenges vs. separation problems.

In addition to understanding how scale inhibitors affect the bulk-solution precipitation process, it is important to assess how efficient inhibitors are in controlling the nucleation, growth, and adhesion of scale in metal surfaces. How Minimum-Inhibitor Concentration (MIC) and Sub-MIC Concentrations Affect Bulk Precipitation and Surface-Scaling Rates presents the results of an experimental program conducted to assess the efficiency of polyphosphinocarboxylic acid (PPCA) in inhibiting barium sulfate scale formation in the bulk solution and on a metal surface over a range of concentrations and test temperatures. Simple schematic models of the bulk- and surface-scaling regimes and the corresponding inhibition process are presented.

The next paper, Silica-Scale Inhibition for Steam Generation in OTSG Boiler, demonstrates that silica-scale inhibitors can be used in steam generation in a once-through-steam-generation (OTSG) boiler. The laboratory results were corroborated on an industrial OTSG boiler in operating conditions. Results show that use of silica-scale inhibitors instead of silica removal can result in substantial cost saving.

The paper Study of Calcium Carbonate Precipitation in the Near-Well Region Using 47Ca2+ as Tracer discusses the development of a new method for studying calcium carbonate precipitation in laboratory experiments using the gamma-emitting tracer 47Ca2+. The advantage of this method is its high sensitivity for the onset of precipitation and its ability to visualize the scale distribution, which is not readily accomplished with conventional methods.

Benchmarking the Formation Damage of Drilling Fluids presents a unified test protocol for formation-damage testing. The protocol is functional, rather than a detailed instruction, with respect to laboratory-work processes and the handling of laboratory equipment. Options for diagnostic formation-damage assessments and minimum requirements to scale up formation-damage measurements to field scale are also presented.

Prediction of formation damage that occurs while drilling horizontal wells is a critical point for optimizing an oilfield development. Near-Wellbore Formation-Damage Effects on Well Performance―A Comparison Between Underbalanced and Overbalanced Drilling describes a numerical approach to simulate near-wellbore damage caused by underbalanced drilling. The impacts of formation damage on well productivity are simulated by the numerical model and are compared for both underbalanced and overbalanced drilling.

Almost all deep sour-gas reservoirs and many of our oil reservoirs contain elemental sulfur as dissolved species. Reduction in pressure and temperature during production operation can result in deposition of elemental sulfur in the reservoir, wellbore, and surface facilities. In addition, many oil reservoirs suffer from simultaneous sulfur and asphaltene deposition problems. Formation Damage Caused by Simultaneous Sulfur and Asphaltene Deposition presents the results of dynamic-flow experiments conducted using different crude oils of different sulfur and asphaltene concentrations, under different flow rates. The results show that the increase of oil-flow rates increases the formation damage caused by sulfur and asphaltene deposition in the reservoir rock. As such, reduction of flow rates may significantly reduce the sulfur- and asphaltene-induced formation damage.

The next paper, Optimizing Filtrate Design To Minimize In-Situ and Wellbore Damage to Water-Wet Reservoirs During Drill-In, presents laboratory data demonstrating the benefits of a special surfactant molecule engineered to pass through a drill-in-fluid filter cake along with other filtrate components to maximize wellbore productivity. Functionally, the addition of this surfactant to the water-based drill-in fluids can prevent the formation of in-situ water/oil emulsions, inhibit the adsorption of polymers onto the rock surfaces, and reduce the risk of water blockage.

The paper Productivity of Selectively Perforated Horizontal Wells investigates the effects of selective perforating on horizontal-well performance. The theoretical investigation shows that the ratio of total perforated length to the drilled well length is the most dominant parameter controlling the long-term performance of selectively perforated horizontal wells. Other important parameters include the degree of formation and perforation damage.

Liquid loading in the wellbore has been recognized as a severe problem in gas production for many years. Accurate prediction of the problem is critical to taking timely measures to resolve the problem. Although several investigators have suggested methods to predict the problems, these methods are not easy to use, and results often show discrepancies. A Systematic Approach to Predicting Liquid Loading in Gas Wells presents an accurate and easy-to-use method for predicting the minimum gas-production rate for the continuous removal of liquids from gas wells.

Two-phase-flow modeling for gas-condensate wells has not received as much attention as that for oil wells. Simplified Wellbore-Flow Modeling in Gas/Condensate Systems advocates the use of a two-component homogeneous model to circumvent issues with any rigorous two-phase-flow modeling, such as delineating flow-pattern boundaries, estimating slip between phases, and performing flash calculations.

The next paper, Including Nonequilibrium Relaxation in Models for Rapid Multiphase Flow in Wells, presents models that can be incorporated into conventional reservoir simulations for accurate description of nonequilibrium conditions. These models are applicable for two-phase (oil/gas and water/gas) and three-phase (oil/water/gas) well-fluid systems.

Heat transfer across the insulation of pipelines and wellbores presents a unique problem affecting flow efficiency. Although sophisticated computer programs are available for predicting fluid temperatures, their accuracies suffer from numerical treatments because long pipe segments have to be used to save computing time. The paper, A Simple Model for Predicting Heat Loss and Temperature Profiles in Insulated Pipelines, presents three analytical heat-transfer solutions for predicting heat loss and temperature profiles in thermal-insulated flow conduits.

The next paper, Unified Model of Heat Transfer in Gas/Liquid Pipe Flow, presents a unified model of multiphase heat transfer for different flow patterns of gas/liquid pipe flow at all inclinations from –90° to +90° from horizontal.

Analysis of Oil-/Water-Flow Tests in Horizontal, Hilly Terrain, and Vertical Pipes provides new experimental data of flow pattern, water holdup, and pressure drop particularly measured at horizontal, hilly terrain, and vertical conditions with large-diameter pipes.

Friction pressure of fluids in tubing can be drastically reduced by adding long-chain polymers or surfactants to fluids being pumped. Effect of Coiled-Tubing Curvature on Drag Reduction of Polymeric Fluids presents experimental results of the effect of coiled-tubing curvature on the drag-reduction behavior of polymeric fluids in turbulent flow.

Granular-Polymer-Gel Treatment Successful in Daqing Oil Field presents the results of a field trial in which granular polymer gel was used as a blocking agent. The blocking agent improved oil production and substantially decreased the water production.

And finally, the last paper in this issue, Identification and Resolution of Water-Treatment Performance Issues on the 135 D Platform, describes the means by which the fundamental causes of the water-treatment performance problems on the 135 D platform, Campos basin, were identified and successfully resolved.

In closing, this issue of the journal contains 18 technical articles covering a range of interest related to production and facilities. I hope that between them, they contain something that is of interest and value to every reader of SPE Production & Operations. Furthermore, I wish everyone a happy and prosperous 2006.

As ever, if you have any comments—positive or negative—about the content of this issue, I encourage you to send them to me at syed@chevron.com.