Assessment of Damage to Porous Media resulting from Reinjection of Produced Water
produced water; oil-in-water emulsion; Berea sandstone; damage formation;
injectivity.
The water injection has been widely applied as secondary recovery method in the oil industry. Water is injected with the aim of preventing reservoir pressure decline and directing the oil towards production wells. However, over the years, there has been an increase in the generation of produced water prompting the search for alternatives to reuse this fluid, with reinjection being one of these options. The produced water contains various contaminants, including dispersed oil droplets in the aqueous phase (such as oil- in-water emulsion). The components present in the water can cause different formation damages and, therefore, it requires a deeper understanding. Thus, the objective of this work is to develop stable oil-in-water emulsions and evaluate the impact of each emulsion component on formation damage. To achieve this, emulsions will be formulated with NaCl 3 wt% (aqueous phase), Triton TX-100 (surfactant) and dodecane (oily phase), varying the surfactant concentration, stirring speed and oil concentration. The stability will be analyzed through the distribution of the average size and volumetric concentration of the dispersed phase. Coreflooding tests will be conducted to assess formation damage, using emulsions with different oil concentrations, which will be injected into Berea sandstone plugs with different permeabilities.