Heavy oil refining method

Abstract

A refined oil is obtained by using a heavy oil having a hydrogen content of 12 wt % or less as a feed oil, and after carrying out a solvent extraction process such that the hydrogen content increases by 0.2 wt % over that of the feed oil, hydrorefining process is carried out such that the hydrogen content increases by 0.5 wt % over the extracted oil. Thereby, an inexpensive heavy oil can be used as a feedstock, and using a simple and reliable method, refined oil can be produced.

1 . A refining method for heavy oil comprising the steps of: 
 using a heavy oil having a hydrogen content of 12% or less as a feed oil, carrying out a solvent extraction process so that the hydrogen content increases by 0.2 wt % or greater with respect to said heavy oil, and obtaining a deasphalted oil (DAO) as an extracted oil; and    subjecting said deasphalted oil to hydrorefining so that the hydrogen content increases by 0.5 wt % or greater with respect to said deasphalted oil to obtain a refined oil.    
     
     
         2 . A refining method for heavy oil according to  claim 1 , wherein the hydrogen content of said refined oil whose hydrogen content has increased by 0.7 wt % or greater with respect to said feed oil is 11.5 wt % or greater.  
     
     
         3 . A refining method for heavy oil according to  claim 1 , wherein the increase in the hydrogen content of said deasphalted oil is 0.2 to 1.5 wt % over that of said feed oil, and the increase in the hydrogen content of said refined oil is 0.5 to 1.5 wt % over that of said deasphalted oil.  
     
     
         4 . A refining method for heavy oil according to  claim 1 , wherein the hydrogen content of said feed oil is 11 to 12 wt %, the increase in the hydrogen content of the deasphalted oil obtained by said solvent extracting is 0.2 to 1.0 wt % over that of the feed oil, and the increase in the hydrogen content of the refined oil obtained by hydrorefining is 0.5 to 1.0 wt % over that of the deasphalted oil.  
     
     
         5 . A refining method for heavy oil according to  claim 1 , wherein the hydrogen content of said feed oil is less than 11 wt %, the increase in the hydrogen content of said deasphalted oil obtained by said solvent extracting is 0.5 to 1.5 over that of the feed oil, and the increase in the hydrogen content of said refined oil obtained by said hydrorefining is 0.6 to 1.5 wt % over that of said deasphalted oil.  
     
     
         6 . A refining method for heavy oil according to  claim 1 , further comprising carrying out a solvent extraction process so that the total amount of Ni and V in said deasphalted oil is 70 wtppm or less, and the Conradson carbon residue is 15 wt % or less.  
     
     
         7 . A refining method for heavy oil according to  claim 1 , wherein the content of the V+Ni of said refined oil is 2 wtppm or less, the Conradson carbon residue is 1 wt % or less, and the sulfur content is 0.5 wt % or less.  
     
     
         8 . A refining method for heavy oil according to  claim 1 , wherein at least a part of said refining oil is used as the thermal cracking feed oil for light olefin production, and the hydrogen content in this thermally cracked feed oil is 12.0 wt % or greater.