Well Stimulation Using a Microemulsion to Increase Oil Production

Abstract Oil and gas wells are drilled to come into full production as quickly as possible, within the first few months post initial completions. Near-wellbore reservoir formation damage caused by non-polar materials may be remediated through the use of a microemulsions to increase hydrocarbon recovery and/or increase water injection potential. An operator well which was drilled and completed, produced initially for five months in 2018 before it stopped flowing. An acid breaker was pumped, and gas lifted to resume production. The production was sustained for six years after which a decline was observed. This led to a further evaluation of the well; during which a solid waxy substance was found in the tubing and the well was shut in. This necessitated deployment of a microemulsion breaker fluid to remediate the well. A sample of the solid wax was collected and sent to the laboratory for dissolution test to be conducted. The test was carried out in various ratios of 60 ml: 2 g, 60 ml: 4 g, 60 ml: 6 g) at a temperature of 150°F with a novel microemulsion treatment fluid and the results indicate that the glass and wax surfaces used for simulation were rendered water-wet by the adsorption of surfactants. Once the surface becomes water-wet, it provides an unfavorable condition for the deposition of hydrophobic precipitates, such as wax-paraffin or asphaltene. The waxy sample was observed to have lost its adhesiveness to the glass vial after two hours of testing. On location, after deployment and monitoring of the tubing well head pressure, the waxy substance lost it adhesiveness to the tubing causing a high-pressure differential which increased production without an artificial lift. This technical paper explains the process of candidate selection, design solution, job execution, and resultant production gains from deploying microemulsion-based solution applied in the operator field.