Solvent Extraction Process for Removal of Naphthenic Acids and Calcium from Low Asphaltic Crude Oil

The present disclosure provides a process for obtaining extracted crude oil (ECO) which is substantially free of naphthenic acids, calcium and other impurities from low asphaltic crude oils or their residue fractions by preferential extraction of saturates using at least one solvent. 1. A process for obtaining extracted crude oil (ECO) which is substantially free of naphthenic acids , calcium and other impurities from low asphaltic crude oils or their residue fractions; said process comprising the following steps:a) subjecting the low asphaltic crude oil to preferential extraction of saturates using at least one solvent by vigorously mixing the asphaltic crude oil in at least one form selected from the group consisting of low asphaltic crude oil as such, atmospheric residue of low asphaltic crude oil and vacuum residue of low asphaltic crude oil to obtain a mixture;b) heating the mixture and allowing the heated mixture to settle under gravity to obtain a biphasic mixture with a top layer containing extracted crude oil and solvent and a bottom layer with raffinate containing naphthenic acid, calcium and other impurities;c) separating the top layer from the biphasic mixture; andd) heating the separated top layer to separate the solvent from the extracted crude oil to obtain solvent free extracted crude oil(ECO), said solvent free extracted crude oil being characterized by TAN percentage reduction ranging between 25 to 100%, calcium percentage reduction ranging between 40 to 99%, nickel percentage reduction ranging between 75 to 95%, vanadium percentage reduction ranging between 65 to 95%, sulphur percentage reduction between 2 to 45%, nitrogen percentage reduction ranging between 25 to 50% and CCR percentage reduction ranging between 75 to 97%; said percentages reductions being calculated on the basis of the respective proportions of these impurities in the asphaltic crude oil which is the starting material as employed in method step a.2. The process as claimed in ...