Process for deasphalting a heavy hydrocarbon feedstock
AssigneeCompagnie de Raffinage et de Distribution Total France
InventorsDidier Chombart, Francois X. Cormerais, Michel Laborde
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Abstract
A process for deasphalting a heavy hydrocarbon feedstock, comprising two stages of precipitation from the feedstock of an asphaltene fraction alone or, alternatively, of a resin fraction along with the asphaltene fraction, by means of a heavy solvent and a light solvent, respectively, is disclosed. In accordance with the process, the heavy solvent and the light solvent both contain, in different proportions, at least one hydrocarbon having 3 carbon atoms and at least one hydrocarbon having at least 5 carbon atoms, the proportion of the hydrocarbon having 3 carbon atoms being higher in the light solvent than in the heavy solvent.
Claims19
A process for the deasphalting of a heavy hydrocarbon feedstock containing an oil phase and an asphaltic phase, the asphaltic phase containing a light resin fraction and a heavy asphaltene fraction;
- the process comprising a first treatment step of mixing said feedstock with a first solvent containing substantially only at least one or more hydrocarbons constituting a C.sub.3 species having 3 carbon atoms and at least one or more hydrocarbons constituting a C.sub.5+ species having at least 5 carbon atoms;
- the two species of hydrocarbons being present in the first solvent in a given proportion so as to yield as products of said first treatment step a precipitate including at least said asphaltene fraction and a supernatant including at least said oil phase, with said resin fraction being present only in one of said precipitate and said supernatant;
- separating said precipitate from said supernatant;
- a second treatment step of mixing that product of the first step which contains the resin fraction with a second solvent containing only at least one or more hydrocarbons constituting a C.sub.3 species having three carbon atoms and at least one or more hydrocarbons constituting a C.sub.5+ species having at least 5 carbon atoms;
- the two species of hydrocarbons being present in the second solvent in a given proportion different from their proportion in the first solvent such that in the event that said second solvent is mixed with said precipitate containing said resin fraction, the second solvent has fewer C.sub. 3 species than said first solvent and in the event that said second solvent is mixed with said supernatant containing said resin fraction the second solvent has more C.sub.3 species than said first solvent;
- ultimately separating said solvents for recycling;
- the proportions of said species in said first and second solvents being such that said process yields a seperate deasphalted oil phase with a Conradson carbon value of 10 or less, a separated resin fraction, and a separate asphaltene fraction with a softening point of 150.degree. C. or higher.
A process for deasphalting a heavy hydrocarbon feedstock containing an oil phase and an asphaltic phase, the asphaltic phase containing a light resin fraction and a heavy asphaltene fraction;
- the process comprising a first treatment step of mixing said feedstock with a first solvent containing at least one hydrocarbon having 3 carbon atoms and at least one hydrocarbon having at least 5 carbon atoms, the two kinds of hydrocarbons present in the first solvent being in a specified proportion so as to yield an oil-containing mixture with most of said first solvent and also to yield a separate asphaltene-containing mixture with a little of said first solvent, with only one of said mixtures being an interim mixture and containing resin and the other of said mixtures being the first mixture;
- a second treatment step of mixing said resin-containing interim mixture with a second solvent containing at least one hydrocarbon having 3 carbon atoms and at least one hydrocarbon having at least 5 carbon atoms, the two kinds of hydrocarbons present in the second solvent being in a specified proportion different from their proportion in the first solvent so as to yield a resin-containing second mixture with at least some of said second solvent and also to yield a third mixture with at least some of said second solvent and with whichever of the oil or asphaltene was present in said interim mixture;
- and third through fifth treatment steps to separate solvent from the first, second and third mixtures formed by the first and second treatment steps to yield three separate products derived from said feedstock including a deasphalted oil phase with a Conradson carbon value of 10 or less;
- a resin fraction;
- and an asphaltene fraction with a softening point of 150.degree. C. or higher.
A process for deasphalting a heavy hydrocarbon feedstock containing an oil phase and an asphaltic phase, the asphaltic phase containing a light resin fraction and a heavy asphaltene fraction, to yield three separate principal products including a deasphalted oil phase with a Conradson carbon value of 10 or less;
- a resin fraction;
- and an asphaltene fraction with a softening point of 150.degree. C. or higher;
- the process comprising a first treatment step of mixing the hydrocarbon feedstock with a first solvent containing at least one C.sub.3 species of hydrocarbon having 3 carbon atoms and at least one C.sub.5+ species of hydrocarbon having at least 5 carbon atoms, the two hydrocarbon species being present in the first solvent in a specified proportion to yield a first mixture which apart from any solvent principally contains oil and a second mixture which apart from any solvent principally contains asphaltenes, with one of said mixtures also containing resin as a second principal ingredient thereof;
- a second treatment step of mixing the mixture containing the resin with a second solvent containing at least one C.sub.3 species of hydrcarbon having 3 carbon atoms and at least one C.sub.5+ species of hydrocarbon having at least 5 carbon atoms, the two hydrocarbon species being present in the second solvent in a specified proportion different from their proportion in the first solvent to yield a third mixture which apart from any solvent principally contains resin and a fourth mixture which apart from any solvent principally contains the other principal ingredient derived from the mixture treated with said second solvent;
- and further treatment steps to separate the oil, resin and asphaltene from the solvents mixed therewith to yield said three separate products.
Dependencies are inferred from the claim text.