US 12,077,714 B2
Needle coke production from HPNA recovered from hydrocracking unit
Omer Refa Koseoglu, Dhahran (SA); and Ali Alzaid, Dammam (SA)
Assigned to SAUDI ARABIAN OIL COMPANY, Dhahran (SA)
Filed by SAUDI ARABIAN OIL COMPANY, Dhahran (SA)
Filed on Dec. 11, 2019, as Appl. No. 16/710,856.
Prior Publication US 2021/0179945 A1, Jun. 17, 2021
Int. Cl. C10G 67/06 (2006.01); C10B 57/04 (2006.01); C10B 57/06 (2006.01); C10B 57/00 (2006.01)
CPC C10B 57/06 (2013.01) [C10B 57/045 (2013.01); C10B 57/005 (2013.01)] 14 Claims
OG exemplary drawing
 
1. A process for the treatment of a hydrocracking unit bottoms stream containing heavy poly-nuclear aromatic (HPNA) compounds to produce needle coke, the process comprising:
a. feeding the hydrocracking unit bottoms stream, comprising 0.5 wt % or less sulfur-containing compounds and 50 ppmw or less nitrogen-containing compounds, and a non-polar solvent stream to a solvent de-asphalting unit to remove a portion of the metals, asphaltenes, nitrogen-containing compounds, and sulfur-containing compounds, producing a deasphalted oil (DAO) stream containing the DAO and the non-polar solvent, wherein the DAO has a boiling point between 450 and 800° C. and the non-polar solvent has an overall Hildebrand solubility parameter of less than 8.0 (cal/cm3)1/2 and a complexing solubility parameter of less than 0.5 and a field force parameter of less than 7.5;
b. contacting the DAO stream containing the DAO and the non-polar solvent with an effective amount of adsorbent material in an adsorption unit to produce an adsorbent laden with HPNA compounds and an adsorbent treated hydrocarbon stream, the adsorbent treated hydrocarbon stream further comprising the non-polar solvent;
c. feeding the adsorbent treated hydrocarbon stream comprising the non-polar solvent to an intermediate separation column to separate the non-polar solvent from the adsorbent treated hydrocarbon stream;
d. recycling the non-polar solvent to the solvent de-asphalting unit;
e. washing the adsorbent laden with HPNA compounds with one or more polar solvents to extract the HPNA compounds and produce a polar solvent effluent stream, wherein the polar solvent has the overall Hildebrand solubility parameter greater than 8.5 (cal/cm3)1/2, and the complexing solubility parameter of greater than 1 and field force parameter of greater than 8;
f. recovering and introducing the polar solvent effluent stream from the adsorption unit into a separation unit;
g. recovering the one or more polar solvents from the separation unit for re-use as the one or more polar solvents;
h. recovering the HPNA compounds from the separation unit;
i. subjecting the HPNA compounds to a delayed coking process for the formation of needle coke having a sulfur content of 0.2-0.5 wt %, a bulk density between 670 and 720 kg/m3, a nitrogen content of less than or equal to 50 ppmw, nickel content of less than or equal to 7 ppmw, a volatile combustible material of 0.5 wt % or less, maximum ash content of 0.1 wt %, a maximum moisture content of 0.1 wt %, and a trace vanadium content.