US 12,270,008 B2
Method for hydrotreating and recycling waste lubricating oil
Bin Liu, Qingdao (CN); Yongming Chai, Qingdao (CN); Chenguang Liu, Qingdao (CN); Yuan Pan, Qingdao (CN); Yichuan Li, Qingdao (CN); Kongyuan Zhang, Qingdao (CN); and Yunqi Liu, Qingdao (CN)
Assigned to CHINA UNIVERSITY OF PETROLEUM (EAST CHINA), Qingdao (CN)
Appl. No. 18/036,192
Filed by CHINA UNIVERSITY OF PETROLEUM (EAST CHINA), Qingdao (CN)
PCT Filed Jan. 10, 2022, PCT No. PCT/CN2022/071133
§ 371(c)(1), (2) Date May 10, 2023,
PCT Pub. No. WO2022/100763, PCT Pub. Date May 19, 2022.
Claims priority of application No. 202011257524.0 (CN), filed on Nov. 12, 2020.
Prior Publication US 2024/0010944 A1, Jan. 11, 2024
Int. Cl. C10M 175/00 (2006.01); B01J 31/02 (2006.01); B01J 37/04 (2006.01); B01J 37/20 (2006.01); C10G 67/14 (2006.01); C10N 60/02 (2006.01)
CPC C10M 175/0016 (2013.01) [B01J 31/0239 (2013.01); B01J 37/04 (2013.01); B01J 37/20 (2013.01); C10G 67/14 (2013.01); C10M 175/0058 (2013.01); B01J 2231/645 (2013.01); B01J 2531/64 (2013.01); B01J 2531/842 (2013.01); B01J 2531/847 (2013.01); C10G 2300/1007 (2013.01); C10N 2060/02 (2013.01)] 17 Claims
OG exemplary drawing
 
1. A method for hydrotreating and recycling waste lubricating oil, comprising the steps of:
S100) removing small-particle mechanical impurities from the waste lubricating oil with a filter; and separating free water and a portion of light hydrocarbons from the waste lubricating oil in a flash distillation column;
S200) mixing a bottom product obtained from the flash distillation column in S100 with hydrogen gas and a self-sulfurizing oil-soluble transition metal catalyst; and pre-hydrotreating the mixture in a slurry bed hydrogenation reactor;
S300) separating a reaction effluent obtained in S200 to obtain hydrogen-rich gas and a liquid product;
S400) separating the liquid product obtained in S300 with two-stage hydrocyclone separators to obtain a liquid product and a tailing residue; allowing the tailing residue to enter a solvent recovery tower; and discharging a tower bottom effluent as a solid residue from the solvent recovery tower;
S500) obtaining a slurry bed pre-hydrotreating product, which includes the liquid product from the two-stage hydrocyclone separators and a solvent from the solvent recovery tower;
S600) mixing the slurry bed pre-hydrotreating product with hydrogen gas; and streaming the mixture sequentially through a hydrofining reactor, an isomerization-dewaxing reactor and a supplementary refining reactor while the mixture is caused to react in turn through contact with a hydrorefining catalyst, an isomerization-dewaxing catalyst and a supplementary refining catalyst; and
S700) separating an output material in S600 to obtain a naphtha fraction, a diesel fraction and a lubricant base oil fraction, wherein:
the waste lubricating oil enters the slurry bed hydrogenation reactor through a bottom of the slurry bed hydrogenation reactor and then flows upwards after the waste lubricating oil is mixed with the hydrogen gas and the self-sulfurizing oil-soluble transition metal catalyst in the slurry bed hydrogenation reactor;
the self-sulfurizing oil-soluble transition metal catalyst includes one of molybdenum, nickel, iron and cobalt; and
S400 further includes setting the two-stage hydrocyclone separators to operate at a temperature of 50-180° C.