Managing the Impact of in Situ Fines Migration in Production Optimization – A Case History from a Niger Delta Field

Abstract

In the oil and gas business, a key strategy of well management is the deployment of the right tools and knowledge to enable continuous and optimized production. One of such tools is Matrix acidizing - A stimulation activity designed to remove wellbore damage and improve well inflow. The ability to sustain optimal production from most wells after acidization is often hampered with further fines migration problems and this requires specialized treatment to mitigate. WELL-001 quit production and was re-entered for a workover in 2018, to recomplete shallower on the same reservoir sand and restore production, however, post workover and subsequent clean up, the well failed to sustain flow. Two additional stimulation operations were also unsuccessful despite gas lift assistance. An Integrated review was held which identified key damage mechanisms impeding flow; deep fines migration which are not well handled by conventional stimulation recipes, emulsion and impairment from Loss Circulation Material (CaCO3 + XCD Polymer). A Novel solution was identified which included an Ultra-Thin Tackifying Agent (UTTA) as part of the stimulation cocktail with the primary purpose of stabilizing the fines at source and preventing further migration with the flowing fluids. The treatment was deployed successfully and the well lifted immediately, achieving a rate of 800 bopd vs a planned potential of 650 bopd. The impact of this success is not only evident in production but also in resource volume estimation and booking.