Dispersion and removal of asphaltene in heavy oil, Tahe Oilfield

Due to the high content of asphaltene in crude oil in the Tahe Oilfield, wellbore plugging was very common as reservoir/wellbore pressure and temperature field changed in oil production process. With X-ray fluorescence spectrometry, component analysis and solvent extraction method, the plugging composition was analyzed, among which over 90% was organic matter. Asphaltene accounted for over 38% in the organic matter. A new asphalt plugging removal agent was innovated and evaluated. The highest dissolution rate at 60 ℃ could reach 2.956 mg/(mL·min). For the crude oil with colloid unstable index bigger than 0.9, asphaltene deposition could be inhibited by adding the new asphalt plugging removal agent with mass concentration of 1%.