Multi-stage process for deasphalting resid, removing catalyst fines from decanted oil and apparatus therefor

A method of purifying decanted oil obtained from a catalytic cracker and containing cracking catalyst fines comprising:

• mixing a hydrotreated resid with said decanted oil to provide a decanted oil-resid mixture containing cracking catalyst fines,
• mixing a non-aromatic hydrocarbon solvent with said decanted oil-resid mixture containing said cracking catalyst fines wherein said non-aromatic hydrocarbon solvent is selected from the group consisting of hydrocarbon solvents having 3 to 7 carbon atoms and mixtures thereof,
• conveying said decanted oil-resid mixture containing said cracking catalyst fines and said solvent to a first separator,
• maintaining said first separator at a temperature and pressure at or below the critical conditions of said solvent, to form a substantially fine-lean decanted oil-solvent phase and a liquid phase of resid and asphaltene in said first separator,
• recovering fine-lean decanted oil-solvent mixture from said first separator,
• conveying said fine-lean decanted oil-solvent phase from said first separator to a second separator,
• maintaining said second separator at a temperature and pressure to separate substantially catalyst free decanted oil from said fine-lean decanted oil-solvent phase,
• recovering said solvent from said fine-lean decanted oil-solvent phase in said second separator, and
• recovering said substantially catalyst free decanted oil from said second separator.

A hydrotreating process comprising the steps of:

• hydrotreating a resid with hydrogen in the presence of a hydrotreating catalyst to produce a hydrotreated resid, containing hydrotreating catalyst fines;
• mixing a fraction of the hydrotreated resid with a decanted oil containing cracking catalyst fines to produce a mixture,
• solvent extracting a catalyst enriched asphaltene stream from said mixture with a solvent comprising a non-aromatic hydrocarbon solvent containing 3 to 7 carbon atoms, and combinations thereof;
• said catalyst enriched asphaltene stream comprising asphaltenes and a substantial amount of said hydrotreating catalyst fines and said cracking catalyst fines;
• separating a substantially catalyst free stream of resins of deasphalted oil from said solvent extracted mixture;
• separating a spent solvent stream of solvent from said solvent extracted mixture;
• and
• hydrocracking said catalyst free stream of resins and deasphalted oil in a hydrotreating unit with hydrogen in the presence of a hydrogenation catalyst to produce upgraded oil.

A hydrotreating process, comprising the steps of:

• substantially desalting crude oil;
• heating said desalted crude oil in a pipestill furnace;
• pumping said heated crude oil to a primary distillation tower;
• separating said heated crude oil in said primary distallation tower into streams of naphtha, kerosene, primary gas oil, and primary reduced crude oil;
• pumping said primary reduced crude oil to a pipestill vacuum tower;
• separating said primary reduced crude in said pipestill vacuum tower into streams of wet gas, heavy gas oil, and vacuum reduced crude oil providing virgin unhydrotreated resid oil;
• feeding a composite feed comprising solvent extracted resins, deasphalted oil and said virgin unhydrotreated resid oil to a resid hydrotreating unit comprising a series of ebullated bed reactors;
• injecting hydrogen-rich gases into said ebullated bed reactors;
• conveying resid hydrotreating catalysts to said ebullated bed reactors;
• ebullating said composite feed comprising said solvent extracted resins, deasphalted oil and said virgin unhydrotreated resid oil with said hydrogen-rich gases in the presence of said hydrotreating catalyst in said ebullated bed reactors under hydrotreating conditions to produce upgraded hydrotreated resid oil containing hydrotreating catalyst fines;
• separating said upgraded hydrotreated resid oil into vacuum tower bottoms comprising vacuum resid oil containing said hydrotreating catalyst fines;
• mixing at least a portion of said vacuum tower bottoms with a decanted oil containing cracking catalyst fines to form a mixture,
• solvent extracting a catalyst laden stream from said mixture with a solvent comprising a non-aromatic hydrocarbon solvent and mixtures thereof containing 3 to 7 carbon atoms, in stage one of a two stage solvent extraction unit,
• said catalyst laden stream comprising substantially derisined asphaltenes and a substantial amount of said hydrotreating catalyst fines and a cracking catalyst fines;
• separating the residual solvent extracted mixture in stage two of said solvent extraction unit into two catalyst lean streams having a substantially smaller concentration of catalyst fines than said mixtures, said first catalyst lean stream comprising spent solvent, and said second catalyst lean stream comprising resins and substantially deasphalted oil, and;
• recycling said second catalyst lean stream of resins and deasphalted oil to said ebullated bed reactors as part of said composite feed.

A method of deasphalting a hydrotreated resid and substantially removing cracking catalyst fines from decanted oil containing cracking catalyst fines, comprising:

• mixing said decanted oil containing cracking catalyst fines with said hydrotreated resid to provide a decanted oil-resid mixture,
• mixing a non aromatic C.sub.3 to C.sub.7 hydrocarbon solvent or mixtures thereof with said decanted oil-resid mixture before a first separator,
• feeding said decanted oil-resid mixture to said first separator,
• maintaining a temperature and pressure in said first separator at or below the critical conditions of said solvent to solvent extract asphaltene and a deasphalted oil-solvent mixture,
• recovering a substantially deresined solvent-extracted asphaltene from said first separator wherein said asphaltene contains a substantial amount of said cracking catalyst fines,
• recovering a substantially deasphalted oil-solvent mixture containing cracking catalyst fines with less than 20 ppm silica and less than 20 ppm alumina from said first separator,
• feeding said substantially deasphalted oil-solvent mixture from said first separator to a second separator,
• maintaining the temperature and pressure of said second separator temperature and pressure to solvent extract a substantially deasphalted oil and solvent from said substantially deasphalted oil-solvent mixture,
• recovering a substantially deasphalted oil containing cracking catalyst fines with less than 20 ppm silica and less than 20 ppm alumina, from said second separator,
• recovering solvent from said second separator, and
• recycling at least a portion of said solvent from said second separator to said first separator.