Effect of Reservoir Mineralogy on Asphaltene Structure and Remediation Strategy Efficiency

For many years, formation damage caused by asphaltene precipitation and deposition has been an issue. The most detrimental impacts are changes to wettability, permeability, and flow area, which ultimately reduce production. To this end, several remediation methods, with considerable economic ramifications, have been adopted, including mechanical removal of the deposits or injection of chemicals to dissolve the deposits. Due to its advantages over mechanical procedures, chemical injection has been used extensively in the industry to remove asphaltene deposits; nonetheless, this method does not completely remove all the deposits. Xylene and petroleum naphtha are two of the most effective fluids used for asphaltene deposit remediation, with their effectiveness based on how aromatic the asphaltene deposit is. Considering this, the effectiveness of remedial activities will be impacted by changes in the aromaticity or structural characteristics of asphaltene. Therefore, the purpose of this study is to determine how reservoir rock mineralogy affects the structural characteristics of asphaltene molecules and how those characteristics affect remediation efforts. X-ray diffraction, Fourier-transform infrared spectroscopy, Rock-Eval analysis, Raman spectroscopy, and elemental analysis were used in this investigation to analyze the asphaltene samples. Furthermore, the effectiveness of xylene as an asphaltene remediation fluid was examined. The results show that the asphaltene samples from the Arab light, medium, and heavy crude oil samples are roughly the same in terms of composition but vary by structural makeup. Furthermore, the asphaltene samples from these crude oils lack the carboxylic functional group that gives most carbonate rocks their oil wetness, leading to intermediate wetness in the analyzed situations. Additionally, rock mineralogy has an impact on the structural characteristics of asphaltene, which in turn impacts how well remediation fluids work to clear up asphaltene deposits.