%D 2013
%C Jakarta
%T Effects of precipitation inhibitor on ASP performance in carbonate reservoirs
%V 1
%O cited By 8; Conference of SPE Asia Pacific Oil and Gas Conference and Exhibition, APOGCE 2013: Maximising the Mature, Elevating the Young ; Conference Date: 22 October 2013 Through 24 October 2013; Conference Code:103383
%K Carboxylic acids; Exhibitions; Oil well flooding; Petroleum reservoir evaluation; Polymers; Reservoirs (water); Surface active agents, Acid concentrations; Alkali concentrations; Alkaline surfactant polymers; Carbonate reservoir; Compatibility test; Permeability reduction; Precipitation inhibitors; Sandstone reservoirs, Ascorbic acid
%I Society of Petroleum Engineers
%L scholars3857
%A S.A. Kalwar
%A K.A. Elraies
%P 522-527
%X Field performance of ASP technique has achieved technically successful and economically feasible results for sandstone reservoirs. However, little attention has been given to ASP application in carbonate reservoirs. The main constraint of ASP flooding in carbonate reservoir is the presence of calcite, dolomite and calcium sulfate minerals. These minerals react with the added chemicals to form insoluble salts known as precipitations. Therefore, an Alkaline-Surfactant-Polymer formulation was developed by incorporating acrylic acid as a precipitation inhibitor or protection agent to overcome the precipitation problems caused by reservoir minerals and brine compositions. The performance of the Acrylic Acid (AA) with an ASP formulation was estimated using sodium metaborate and three types of high tolerant surfactants for possible screening. Feasibility of applying AA with ASP formula was demonstrated by comprehensive fluid-fluid and fluid-rock compatibility tests. Static and dynamic experiments were conducted for monitoring precipitations and permeability reduction using a limestone core samples. Hardbrine composition of 59,000 ppm was used to prepare the ASP formulations in the presence and absence of AA. As results, all chemicals including, alkalis, surfactants, and polymers were incompatible with the hardbrine used in this study. Precipitations were generated from the first day of mixing. However, the presence of acrylic acid showed excellent properties in preventing precipitations and all solutions remained clear for 30 days at 80 °C. The optimum acid concentration was found to be proportional to alkali concentration using acid to alkali weight ratio of 0.6:1.0. Using the optimum acid to alkali ratio, the permeability reduction caused by precipitations was significantly improved. This might add more advantages to ASP process in which hardbrine water can be used instead of softened water. Copyright 2013, Society of Petroleum Engineers.
%J Society of Petroleum Engineers - SPE Asia Pacific Oil and Gas Conference and Exhibition, APOGCE 2013: Maximising the Mature, Elevating the Young