Enhanced methods for solvent deasphalting of hydrocarbons

Abstract

Improvements to open-art Solvent Deasphalting (SDA) processes have been developed to reduce capital and operating costs for processing hydrocarbon streams are provided whereby open art SDA scheme is modified to include appropriately placed mixing-enabled precipitators (MEP's) to reduce solvent use requirements in an asphaltene separation step and to increase overall reliability for SDA processes, particularly suitable for Canadian Bitumen. When integrated with a mild thermal cracker, the improved SDA configuration further improves crude yield to be pipeline-ready without additional diluent and for use to debottleneck existing facilities such as residue hydrocrackers and coking units.

1 . A Mixing Enabled Precipitator (MEP) supporting a continuous process to completely and rapidly mix a heavy hydrocarbon stream with a light hydrocarbon stream for enhanced mass transfer to accelerate precipitation of solid asphaltenes by changing the solubility characteristics of asphaltene particles from the heavy hydrocarbon stream in a resulting blended stream for downstream separation. 
     
     
         2 . The device of  claim 1  where the precipitation is nearly instantaneous with the mixing. 
     
     
         3 . The device of  claim 1  which enhances mass transfer by disentangling hydrocarbon chains. 
     
     
         4 . The device of  claim 1  which changes the characteristics of asphaltene molecules by cleaving side chains of included Canadian bitumen molecules producing additional viable hydrocarbon product. 
     
     
         5 . The device of  claim 1  which enhances mass transfer by intimately mixing two different fluids with comparative viscosity difference of at least 100,000:1. 
     
     
         6 . The device of  claim 1  where solids precipitated in the MEP and transported out of the device are in the 10 μm to 900 μm range. 
     
     
         7 . The device of  claim 1  with a shear number in the range of 3-40. 
     
     
         8 . A Mixing Enabled Precipitator (MEP) placed upstream of a secondary asphaltene extractor supporting a continuous process to completely and rapidly mix a heavy hydrocarbon stream with a light hydrocarbon stream for enhanced mass transfer to accelerate precipitation of solid asphaltenes by changing the solubility characteristics of asphaltene particles from the heavy hydrocarbon stream in the resulting blended stream for downstream separation. 
     
     
         9 . The device of  claim 8  where the precipitation is nearly instantaneous with the mixing. 
     
     
         10 . The device of  claim 8  which enhances mass transfer by disentangling hydrocarbon chains. 
     
     
         11 . The device of  claim 8  which changes the characteristics of asphaltene molecule by cleaving side chains of Canadian bitumen molecules it processes, producing additional viable hydrocarbon product. 
     
     
         12 . The device of  claim 8  which enhances mass transfer by intimately mixing two different fluids with comparative viscosity differences of at least 100,000:1. 
     
     
         13 . The device of  claim 8  where solids precipitated in the MEP and transported out of the device are in the 10 μm to 900 μm range. 
     
     
         14 . The device of  claim 8  with a shear number is in the range of 3-40 
     
     
         15 . A Mixing Enabled Precipitator (MEP) placed upstream of a mild thermal cracker to improve the performance of the thermal cracker and increase the yield of bitumen processing supporting a continuous process to completely and rapidly mix a heavy hydrocarbon stream with a light hydrocarbon stream for enhanced mass transfer to accelerate precipitation of solid asphaltenes by changing the solubility characteristics of the asphaltene particles in the blended stream from the heavy hydrocarbon stream for downstream separation. 
     
     
         16 . The device of  claim 15  which provides a homogenized fluid feedstock with untangled asphaltene molecules to improve uniform heat flux for all molecules. 
     
     
         17 . The device of  claim 15  which changes the characteristics of the asphaltene molecule by cleaving side chains of Canadian bitumen molecules producing additional viable hydrocarbon product. 
     
     
         18 . The device of  claim 15  where the shear number is in the range of 1-30. 
     
     
         19 - 35 . (canceled) 
     
     
         36 . The device of  claim 1  where the mixing-enable precipitator can be a mixer, or a pump/mixer combination, generating both pressure for the process and mixing the liquids into a homogenized fluid. 
     
     
         37 . The device of  claim 36  that can accommodate solids, in the range of 10 μm to 900 μm, flowing through it. 
     
     
         38 . The device of  claim 36  that has shear numbers in the range of 3-40 developing sufficient turbulence for instantaneous mixing. 
     
     
         39 . The device of  claim 36  where at least 1 rotor/stator generator is used. 
     
     
         40 . The device of  claim 1  where the MEP and asphalt separator are combined into one operating unit (MEP plus asphaltene separator) for precipitating and separating the precipitated asphaltenes creating a deasphalted oil/solvent mixture and a dry solid asphaltene product. 
     
     
         41 . The device of  claim 40  where the MEP and the asphalt separator are close coupled. 
     
     
         42 . The device of  claim 40  where the MEP and the asphalt separator are separated by a pipe of at least a fraction of an inch to a length suitable in a commercial operating unit.