Dispersion-Based Paraffin Inhibitors Adsorbed in Solid Substrates Affords Long Term Flow Assurance

Abstract

Paraffin deposition, resulting in productivity loss of newly completed wells, is a major source of formation damage and is operationally and financially critical to address with a proven solution. Paraffin inhibitors included in the stimulation treatment have limited long term success due to cost and limitations on the amount of inhibitor that can be added to provide the desired longevity. A dispersion based paraffin inhibitor adsorbed on a high surface area substrate was developed which is compatible with fracturing fluids and affords a long term, cost effective solution to the paraffin deposition problem. Laboratory studies were conducted under simulated field conditions, and the effect of inhibitor on oil properties (pour point, cold finger) as the oil is treated in the proppant pack with adsorbed paraffin inhibitor was investigated. Oils with different paraffinic issues were analyzed in this study. The studies estimate the longevity of treatment and the improvement expected using this treatment for field applications using flow-through column tests. Traditional paraffin inhibitor treatments have provided limited long term performance in wells with paraffin issues. Little protection is provided beyond the perforations when continuously treating into the production fluids through capillary injectors. Additionally, squeeze treatments designed to increase the chemical's contact area by forcing the chemical treatments deeper into the reservoir give limited longevity in high paraffinic wells. In the current study, a novel treatment results in greater amounts of inhibitor placed downhole for prolonged treatment. A combination treatment was recommended whereby a compatible submicron-sized paraffin inhibitor dispersion is added to the fracturing fluid. In addition, a dispersion based paraffin inhibitor was adsorbed onto a proppant-like substrate that can be mixed into the proppant and delivered deep into the formation with fracturing or refracturing treatments, providing enhanced flow assurance management.

The Impact of Ethylene Glycol on Droplet Growth Inhibition in Ethylene Vinyl Acetate Emulsions

“…These achieved properties comply with the stringent requirement for sub-ambient temperature applications, wherein an emulsion must remain stable in the fluid state at all temperature conditions as to secure the injection line from any blockage. 28,33,34 The EG75 system was indeed superior in terms of freezing protection as it displayed no crystallization during cooling. However, the excessive usage of EG limits its application due to the higher operating cost compared to the EG50 system.…”