Reducing the viscosity of heavy oils - by dissolving carbon di:oxide in the oil

摘要

The viscosity of heavy oils with a specific gravity greater than 0.950 is reduced by desalinating the oil and then dissolving CO2 in the oil in a CO2/oil molar ratio of 0.2-0.7 (pref. 0.25-0.5). The CO2 is pref. produced by burning a portion (pref. 0.5-5, esp. 0.8-2.8 wt.%) of the oil. The CO2 is then cleaned and dissolved in the oil under pressure. The process is esp. useful for facilitating pipeline transport of viscous crudes having a 70 deg. C viscosity of at least 1000 cS, e.g. tar-sand oil or Orinoco crude.