Viscosity reduction process of heavy oil by catalytic co-pyrolysis with sawdust

In order to research the viscosity reduction process of heavy oil by catalytic co-pyrolysis with biomass, the catalytic co-pyrolysis experiments of Liaohe heavy oil and sawdust with calcium naphthenate as catalyst were implemented in this paper. The experimental results showed that the viscosity reduction ratio was up to 98% under the optimum reaction conditions with reaction temperature of 350 degrees C, reaction time of 30 min, sawdust content of 5 wt% and catalyst content of 0.05 wt%. To investigate changes in composition and structure of heavy oil before and after reaction, the oil samples were characterized by elemental analysis (EL), vapor pressure osmometry (VPO), gas chromatography-mass spectrometry (GC-MS), H-1 nuclear magnetic resonance (H-1 NMR) and scanning electron microscope (SEM). In addition, the catalytic pyrolysis mechanism was researched to explain the catalytic effect of calcium naphthenate on the co-pyrolysis reaction. Besides, the significant synergetic eff ;ect on viscosity reduction of heavy oil in catalytic co-pyrolysis system was demonstrated further. Finally, liquid products of sawdust pyrolysis were found to be beneficial to viscosity reduction of heavy oil. This work had a certain reference value for utilizing renewable biomass energy in viscosity reduction process of heavy oil.