Waterflooding: Performance Predictions and Surveillance (RE28)
Course Level: Advanced
This five-day course covers the reservoir engineering aspects of waterflooding. The seminar combines geology, rock and fluid properties, and immiscible displacement theory to develop waterflooding prediction techniques and to aid in the evaluation of actual waterflood performance behaviour. Detailed predictions of oil and water producing rates, water injection rates, and recovery efficiency are presented. Selection of waterflood patterns (regular, irregular, peripheral), prediction of sweep efficiency (areal, vertical, and displacement), and an analysis of other variables which control recovery efficiency are included. Also discussed are waterflood surveillance techniques such as production testing, production plots (rate-time, rate-cum, WOR-cum, etc.), VRR analysis, volumetric sweep (reservoir conformance) determination, injection profile testing, pressure transient testing, step-rate testing, Hall plots (pros and cons), pattern balancing, bubble maps, and injection efficiency determination. These surveillance techniques provide the engineer with data required for the efficient management of both new and mature waterfloods. Several waterflood case studies are reviewed. The course content and example problems have been selected to teach and illustrate important concepts.
DESIGNED FOR YOU, IF YOU ARE...
The course is ideally suited for engineers and geologists with several years of waterflood experience; however, the course is presented in a manner so that both beginning and experienced personnel will find the material very useful. The course content and example problems have been selected to teach and illustrate important concepts.
- Factors Controlling Waterflood Recovery
- The end of primary depletion, initial oil in place, displacement sweep efficiency, areal sweep efficiency, vertical sweep efficiency, pressure maintenance versus waterflooding
- Review Of Rock Properties And Fluid Flow
- Wettability, imbibition and drainage concepts, capillary pressure, air permeability, absolute permeability, effective permeability, relative permeability, industry relative permeability correlations
- Determination Of Oil In Place
- Current oil saturation versus initial oil saturation, gas saturation, calibration of log porosity with core porosity, net pay definition, porosity-permeability cutoffs, net pay determination, rock continuity and floodable pay
- Mechanism Of Immiscible Fluid Displacement (Displacement Sweep)
- Compressible versus incompressible flow, fractional flow equations, frontal advance theory, Buckley-Leverett theory, water saturation distribution, performance before breakthrough, performance after breakthrough, effects of gas saturation, gas fillup time, PVT evaluation, reservoir pressure distribution between wells, data requirements, starting time, primary production, and tertiary recovery
- Flood Patterns (Regular And Irregular) And Impact On Areal Sweep Efficiency
- Mobility ratio, basic flood patterns (line drive, five-spot, nine-spot, irregular patterns, and peripheral injections), iso potential lines, streamlines, areal sweep efficiency before and after injected water breakthrough, pattern selections, pattern changes
- Injection Rates And Pressures
- Fluid injectivity, effect of mobility ratio, gas saturation, patterns and formation damage, pattern injectivity before and after fillup, injection rate changes versus time; constant pressure injection versus constant injection rate
- Reservoir Heterogeneity
- Vertical permeability variation, areal permeability variation, detection of stratification, selection of layers, Dykstra-Parsons coefficient, effect of cross flow, vertical sweep efficiency, impact of permeability variation on oil recovery and WOR
- Waterflood Performance Prediction
- Analogy method, industry rules, empirical modes, Dykstra-Parsons (DP) method, Stiles method, Craig-Geffen-Morse (CGM) method, numerical models
- Waterflood Surveillance
- Surveillance objectives, production testing, production plots, limitations of decline curves in water injection projects, pros and cons of WOR versus cumulative plots, instantaneous and cumulative VRR graphs, step-rate tests, Hall plots and limitations, injection profile management, pattern balancing, volumetric sweep determination using oil production data, conformance improvement, injection efficiency analysis, integrated project review, summary of key items in reservoir management, etc