Block processing configurations for base stock production from deasphalted oil

Abstract

Systems and methods are provided for block operation during lubricant and/or fuels production from deasphalted oil. During “block” operation, a deasphalted oil and/or the hydroprocessed effluent from an initial processing stage can be split into a plurality of fractions. The fractions can correspond, for example, to feed fractions suitable for forming a light neutral fraction, a heavy neutral fraction, and a bright stock fraction, or the plurality of fractions can correspond to any other convenient split into separate fractions. The plurality of separate fractions can then be processed separately in the process train (or in the sweet portion of the process train) for forming fuels and/or lubricant base stocks. The separate processing can allow for selection of conditions for forming lubricant fractions, such as bright stock fractions, that have a cloud point that is lower than the pour point.

1 .- 10 . (canceled) 
     
     
         11 . A method for making lubricant base stock, comprising:
 performing solvent deasphalting using a C4+ solvent under effective solvent deasphalting conditions on a feedstock having a T5 boiling point of at least about 370° C., the effective solvent deasphalting conditions producing a yield of deasphalted oil of at least about 50 wt % of the feedstock;   hydroprocessing at least a portion of the deasphalted oil under first effective hydroprocessing conditions comprising first hydrocracking conditions to form a hydroprocessed effluent, the at least a portion of the deasphalted oil having an aromatics content of at least about 50 wt %, the hydroprocessed effluent comprising a sulfur content of 300 wppm or less, a nitrogen content of 100 wppm or less, or a combination thereof;   separating the hydroprocessed effluent to form at least a fuels boiling range fraction, a first fraction having a T 5  distillation point of at least 370° C., and a second fraction having a T 5  distillation point of at least 370° C., the second fraction having a higher kinematic viscosity at 100° C. than the first fraction;   hydroprocessing at least a portion of the first fraction under second effective hydroprocessing conditions, the second effective hydroprocessing conditions comprising second aromatic saturation conditions and second catalytic dewaxing conditions, to form a first catalytically dewaxed effluent comprising a 370° C.+ portion having a first kinematic viscosity at 100° C., the at least a portion of the first fraction being exposed to the second aromatic saturation conditions prior to the second catalytic dewaxing conditions; and   hydroprocessing at least a portion of the second fraction under third effective hydroprocessing conditions, the third effective hydroprocessing conditions comprising third aromatic saturation conditions and third catalytic dewaxing conditions, to form a second catalytically dewaxed effluent comprising a 370° C.+ portion having a second kinematic viscosity at 100° C. that is greater than the first kinematic viscosity at 100° C., the at least a portion of the second fraction being exposed to the third aromatic saturation conditions prior to the third catalytic dewaxing conditions,   wherein the second effective hydroprocessing conditions are different from the third effective hydroprocessing conditions.   
     
     
         12 . The method of  claim 11 , wherein the second aromatic saturation conditions comprise exposing the at least a portion of the first fraction to an amorphous aromatic saturation catalyst. 
     
     
         13 . The method of  claim 11 , wherein the first hydroprocessing conditions further comprise first aromatic saturation conditions, the first aromatic saturation conditions comprising exposing the at least a portion of the deasphalted oil to a demetallization catalyst, the at least a portion of the deasphalted oil being exposed to the demetallization catalyst after exposing the at least a portion of the deasphalted oil to the hydrocracking catalyst. 
     
     
         14 . The method of  claim 11 , wherein the second effective hydroprocessing conditions and third effective hydroprocessing conditions are different based on a difference in at least one of a hydrocracking pressure, a hydrocracking temperature, a dewaxing pressure, and a dewaxing temperature. 
     
     
         15 . The method of  claim 11 , further comprising recycling at least a portion of the second catalytically dewaxed effluent as part of the at least a portion of the deasphalted oil, as part of the at least a portion of the first fraction, or a combination thereof 
     
     
         16 . The method of  claim 11 , wherein the hydroprocessing at least a portion of the first fraction and the hydroprocessing at least a portion of the second fraction comprise block operation of a processing system. 
     
     
         17 . The method of  claim 11 , wherein separating the hydroprocessed effluent further comprises forming an additional fraction having a Ts distillation point of at least 370° C., the method further comprising:
 hydroprocessing at least a portion of the additional fraction under third effective hydroprocessing conditions, the third effective hydroprocessing conditions comprising catalytic dewaxing conditions, to form a third catalytically dewaxed effluent comprising a 370° C.+ portion having a kinematic viscosity at 100° C. of 3.5 cSt or more. 
 
     
     
         18 . A method for making lubricant base stock, comprising:
 performing solvent deasphalting using a C 4+  solvent under effective solvent deasphalting conditions on a feedstock having a T5 boiling point of at least about 370° C., the effective solvent deasphalting conditions producing a yield of deasphalted oil of at least about 50 wt % of the feedstock;   hydroprocessing at least a portion of the deasphalted oil under first effective hydroprocessing conditions comprising first hydrocracking conditions to form a hydroprocessed effluent, the at least a portion of the deasphalted oil having an aromatics content of at least about 50 wt %;   separating the hydroprocessed effluent to form at least a fuels boiling range fraction, a first fraction having a Ts distillation point of at least 370° C., and a second fraction having a Ts distillation point of at least 370° C., the second fraction having a higher kinematic viscosity at 100° C. than the first fraction;   hydroprocessing at least a portion of the first fraction under second effective hydroprocessing conditions, the second effective hydroprocessing conditions comprising exposing the first fraction to a medium pore dewaxing catalyst to form a first catalytically dewaxed effluent comprising a 370° C.+ portion having a first kinematic viscosity at 100° C.; and   hydroprocessing at least a portion of the second fraction under third effective hydroprocessing conditions, the third effective hydroprocessing conditions comprising exposing the second fraction to the medium pore dewaxing catalyst to form a second catalytically dewaxed effluent comprising a 370° C.+ portion having a second kinematic viscosity at 100° C. that is greater than the first kinematic viscosity at 100° C.,   wherein the second effective hydroprocessing conditions are different from the third effective hydroprocessing conditions.   
     
     
         19 . The method of  claim 18 , wherein the medium pore dewaxing catalyst comprises ZSM-5. 
     
     
         20 . The method of  claim 18 , wherein the medium pore dewaxing catalyst comprises 0.05 wt % or less of Group VIII metals. 
     
     
         21 . The method of  claim 18 , wherein the at least a portion of the deasphalted oil comprises a sulfur content of 300 wppm or more. 
     
     
         22 . The method of  claim 18 , wherein at least a portion of the first fraction, at least a portion of the second fraction, at least a portion of the first catalytically dewaxed effluent, at least a portion of the second catalytically dewaxed effluent, or a combination thereof is used as a feed for a steam cracker. 
     
     
         23 . The method of  claim 18 , wherein at least a portion of the second catalytically dewaxed effluent is used as an asphalt blend component. 
     
     
         24 . The method of  claim 18 , wherein separating the hydroprocessed effluent further comprises forming an additional fraction having a T 5  distillation point of at least 370° C., the method further comprising:
 hydroprocessing at least a portion of the additional fraction under third effective hydroprocessing conditions, the third effective hydroprocessing conditions comprising catalytic dewaxing conditions, to form a third catalytically dewaxed effluent comprising a 370° C.+ portion having a kinematic viscosity at 100° C. of 3.5 cSt or more.