Viscosity changes of Heishan coal-oil slurry at coal direct liquefaction condition

Viscosity changes of coal-oil slurry made from Heishan coal and flash oil viscosity variation was studied. The basic data were provided for Heishan coal direct liquefaction by changing concentration of Heishan coal-oil slurry and the heating rate at direct liquefaction conditions. Using autoclave made by Beijing Research Institute of Coal Chemistry and power number method, the viscosity of coal-oil slurry was calculated by recording the changes of autoclave torque, and using it analyzed the reasons for viscosity change. The results show that oil coal slurry viscosity peak has appeared at different concentrations and different heating rates. But viscosity peak appears at different temperatures. The first peak occurs is due to coal swelling. The second peak occurs is due to a high concentration of pre-asphaltene.