Profile Modification in Injection Wells Through Relative Permeability Modifiers: Laboratory Validation and Reservoir Simulation

Abstract

Waterflooding is a well-established technique in the oil industry to improve hydrocarbon recovery in a given reservoir. However, in the absence of profile modification, water injected into the reservoir will go into the high-permeability zones and will bypass the oil-saturated, low-permeability zones. This paper presents the laboratory validation and reservoir simulation of a relative permeability modifier (RPM) used for profile-modification improvement in injection wells. By injecting the RPM within the high-permeability zones, subsequent injected water will be diverted into low-permeability zones to improve the sweep efficiency of the waterflooding project. This RPM is a water-soluble relative permeability modifier initially developed for water control in production wells. The polymer functions by adsorption onto rock surfaces and effectively reduces water flow with little or no damage to hydrocarbon flow. These treatments are extremely easy to mix and pump, and require no post-job shut-in time. This RPM was evaluated in 5- and 10-ft sandpacks to investigate parameters, such as depth of penetration, diversion properties, treatment injection rate, and polymer concentration. Laboratory results indicate this RPM can effectively penetrate through a 10-ft sandpack, providing permeability reduction to water throughout the length of the porous media. In addition, excellent diverting properties were observed while bullheading the treatment in sandpacks in parallel with significant permeability contrast. In addition, a 3-D numerical simulator was used to evaluate the performance of the RPM system under different scenarios and varying parameters, such as (1) permeability contrast between injection zones, (2) presence/absence of shale barriers between injection zones, and (3) treatment volumes, among others. This paper presents the results of these simulations and the impact it has on hydrocarbon and water production and the overall profitability of a particular field. In addition, the field implementation of this technology in injection wells is presented.

New Technologies For Optimizing Energy-Fluid Input And Flow Assurance In Mature Assets

“…Chemical solutions like sealants, RPM (relative permeability modifiers), and water-swellable polymers at both injectors and producers simultaneously can selectively modify the wettability behavior of high permeable zones (Vasquez and Miranda 2010) and allow injectant fluids to move into the un-swept low permeability hydrocarbon zones. Conformance solutions have been successfully used with the spectrum of EOR technologies.…”

Field Implementation of a Relative Permeability Modifier during Stimulation Treatments: Case Histories and Lessons Learned After More than 3,000 Treatments

“…14. Additionally, offset producers observed an increase in oil production and a water cut decrease a few months after the RPM treatment (Vasquez and Miranda, 2010). …”

Novel Relative Permeability Modifier using Polymer Grafted Nanoclay

“…The sealing polymer gel could, in principle, act as a porosity filler material that completely blocks pores of reservoir rock and stops fluids from flowing . In contrast, RPM is a polymer or weak polymer gel that adsorbs onto the surface of pore spaces and/or rents in pore throats. − RPMs are capable of selectively reducing relative permeability to water with little or no effect on oil flow. − The RPM selective blocking mechanisms on fluid phases are still a matter of debate. Many researchers have indicated that a wall effect, as shown in Figure.…”