Field Applications of Low Molecular-Weight Polymer Activated with an Organic Crosslinker for Water Conformance in South Mexico

Abstract

Abstract One of the major challenges faced in the Mexico South region is water management. Water in the oil stream results in extra disposal costs, scale buildup, reduced oil production, and eventually well shut-in (with associated workover costs). Consequently, producing zones are often abandoned in an attempt to avoid water contact, even when the intervals still retain large volumes of recoverable hydrocarbons. Although natural fractures have a positive effect on oil flow, they also include a negative water or gas flow caused by coning effects or conductive streaks between the producing hydrocarbon zone and intervals above or below. If these zones are water producers, they soon impact the productivity of the hydrocarbon zone. An additional problem must be addressed as well: early water breakthrough caused by edge water flowing through faults, natural fractures, etc. Depending on the desired objective, placement techniques vary. However, placement techniques generally can be divided into two types: those involving a workover rig and those that are rig-less. This paper will discuss case histories from southern Mexico that have used a low molecular-weight polymer, activated with an organic crosslinker. The candidate selection process, general job designs, laboratory testing results, etc. performed for water-reduction treatments in this area will be presented. These cases include depleted, highly fractured reservoirs.