Waterflood Monitoring and Management 1 2 Waterflood Monitoring and Management Waterflood Systems Injection System: Water supply system, Injection wells Reservoir System Production System: Production wells, Surface production system Pressure and Temperature Profile of Water Path On-Line Monitoring Oxygen meter Galvanic probe Turbidity meter Removable coupon Removable spool detects level of oxygen in water stream detects level of oxygen - oxygen is directly related to the level of corrosion indicative of the quantity of suspended solids in treated water ascertain a long term corrosion levels ascertains long term corrosion/sealing levels Electrical resistance probe determines short term corrosion level 3 4 1
Waterflood Surveillance Accurate data collection Monthly 3-phase production well tests - Measure oil, water, & gas production during test Daily injection volumes & pressures Maintain & properly use instruments Reservoir pressure history 3D finite difference full-field reservoir simulation Monitor and evaluate flood performance Waterflood Monitoring and Managment Injection Rate is Inadequate Insufficient Productivity Low Displacement Efficiency Low Volumetric Sweep Efficiency High Operating Cost 5 6 Injection Rate is Inadequate Low Permeability Poor Connectivity Heterogeneity Perforation Interval Wellbore Damage Pump, water quantity,..etc Insufficient Productivity Wellbore Damage Poor connectivity High Back Pressure (Liquid Column) Piping sizes Pattern selection 7 8 2
Low Displacement Efficiency Wetting phase Kr, Pc Viscosity ratio Injection, Production Rate Fractures, Connectivity, Barriers. Pattern Low Volumetric Sweep Efficiency Flood Pattern Well Spacing Injection/Production Profile Heterogeneity: Permeability, Connectivity, Fractures, Barriers. 9 10 Improved Waterflood Strategies Pattern Modification & Orientation Monitoring Water Supply Pilot Test Injection Rate & Profile Production Rate & Profile Problem Solving Infill Drilling Waterflood Challenges Monitoring Water Supply Optimum Quality Water: Corrosion and scaling are minimal; free of solid, bacteria, compatible with reservoir material and low cost Purpose of Monitoring Water Supply Obtain good quality injection water, improve water injection profile and pressure 11 12 3
Factors Affecting Water Quality Incompatible Waters Suspended Solids Corrosion Bacteria Growth Objective of Pilot Tests To determine if a process is applicable under the field conditions and if the process has a potential for an economic return from field application Determine the recovery efficiency Understand the process mechanism Obtain operational information Injection Production Treatment Develop a technique to forecast the process performance Evaluate the process economics 13 14 Pilot Test Design Pilot project design Test Site selection Pattern selection Injection & Production Engineering Pilot Implementation Injection & Production Profile Modification Purpose Improve the sweep efficiency to increase ultimate recovery Increase oil production rate to extend the economic life of the field Decrease watercut to lower operating and treating costs 15 16 4
Problem Solving Piping System Modification Increase Injection Rate Pump with Higher Pressure Control Bacteria Use Chemical Infill Drilling Benefites of Infill Drilling Favorable flood pattern orientation Increased interwell connectivity Pattern modification Better injection profile control Increased production profile Accelerating the injection and production rate 17 18 Waterflood Challenges Pump Pressure Limitation Bacteria Contamination Reservoir Damage Formation Blocking Reservoir Plugging Early Water Breakthrough Reservoir Heterogeneity 19 5