Estimation of the Scale Deposits Near Wellbore via Software in the Presence of Inhibitors

Abstract

In this study, computer software was used in order to estimate the scaling tendency of the commingling of two incompatible waters existed in Egyptian oil reservoirs of Gulf of Suez area. The chemical analyses of the two incompatible waters (injection and formation waters) have been used as input data to the computer simulator. The reservoirs characterized by a temperature of 90–127°C, and salinity of 100,000–230,000 ppm. The scaling results for the commingling of both injection and formation water at reservoir temperatures and pressures are recorded. The results of theoretical software and laboratory jar-testing were compared. It was found that mixing of the injection water and formation water may lead to calcium carbonate and barium sulphate scaling at 40% formation water in absence of scale inhibitor. Two types of commercial scale inhibitors (AII and SII) were evaluated using both jar test method and National Association of Corrosion engineers standard test methods. The results showed the mastery of AII over the commercial inhibitor SII in preventing of both scales.