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US 11,767,479 B2Granted
Two-stage hydrocracking process for producing naphtha, comprising a hydrogenation stage implemented downstream of the second hydrocracking stage
AssigneeIfp Energies Nouvelles
InventorsEmmanuelle Guillon, Anne-Claire Dubreuil, Antoine Daudin
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Abstract
The present invention is based on the use of a two-step hydrocracking process for the production of naphtha, comprising a step of hydrogenation placed downstream of the second hydrocracking step, the hydrogenation step treating the effluent resulting from the second hydrocracking step in the presence of a specific hydrogenation catalyst. Furthermore, the hydrogenation step and the second hydrocracking step are performed under specific operating conditions and in particular under quite specific temperature conditions.
Claims20
A process for producing naphtha from a hydrocarbon feedstock containing at least 20% by volume of compounds boiling above 340° C., said process comprising the following steps:
- a) a step of hydrotreating said feedstock in the presence of hydrogen and at least one hydrotreating catalyst, at a temperature of 200° C. to 450° C., under a pressure of 2 and 25 MPa, at a space velocity of 0.1 to 6 h−1 and with an amount of hydrogen introduced such that the litre of hydrogen/litre of hydrocarbon volume ratio is 100 to 2000 Nl/l,
- b) a step of hydrocracking at least one portion of the effluent resulting from step a), the hydrocracking step b) taking place, in the presence of hydrogen and at least one hydrocracking catalyst, at a temperature of 250° C. to 480° C., under a pressure of 2 to 25 MPa, at a space velocity of 0.1 to 6 h−1 and with an amount of hydrogen introduced such that the litre of hydrogen/litre of hydrocarbon volume ratio is 80 to 2000 Nl/l,
- c) a step of high-pressure separation of the effluent resulting from hydrocracking step b) to produce at least a gaseous effluent and a liquid hydrocarbon effluent,
- d) a step of distilling at least one portion of the liquid hydrocarbon effluent resulting from step c) performed in at least one distillation column, from which step the following are drawn off:
- a gaseous fraction,
- at least one fraction comprising the converted hydrocarbon products having at least 80% by volume of products boiling at a temperature below 250° C., and
- an unconverted liquid fraction having at least 80% by volume of products having a boiling point above 175° C.,
- e) optionally a purging of at least one portion of said unconverted liquid fraction containing HPNAs, having at least 80% by volume of products having a boiling point above 175° C.,
- f) a second step of hydrocracking at least one portion of the unconverted liquid fraction having at least 80% by volume of products with a boiling point above 175° C., resulting from step d) and/or optional step e), said step f) being performed in the presence of hydrogen and of at least one second hydrocracking catalyst, at a temperature TR1 of 250° C. to 480° C., under a pressure of 2 to 25 MPa, at a space velocity of between 0.1 and 6 h−1 and with an amount of hydrogen introduced such that the litre of hydrogen/litre of hydrocarbon volume ratio is 80 to 2000 Nl/l,
- g) a step of hydrogenating at least one portion of the effluent resulting from step f) performed in the presence of hydrogen and of a hydrogenation catalyst, at a temperature TR2 of 150° C. to 470° C., under a pressure of 2 to 25 MPa, at a space velocity of 0.1 to 50 h−1 and with an amount of hydrogen introduced such that the litre of hydrogen/litre of hydrocarbon volume ratio is 100 to 4000 Nl/l, said hydrogenation catalyst comprising at least one metal from group VIII chosen from nickel, cobalt, iron, palladium, platinum, rhodium, ruthenium, osmium and iridium alone or as a mixture and not containing any metal from group VIB and a support chosen from refractory oxide supports, and in which the temperature TR2 is at least 10° C. below the temperature TR1,
- h) a step of high-pressure separation of the effluent resulting from the hydrogenation step g) to produce at least a gaseous effluent and a liquid hydrocarbon effluent, and
- i) recycling, into said distillation step d), at least one portion of the liquid hydrocarbon effluent resulting from step h).
9 more elements
A process for producing naphtha from a hydrocarbon feedstock containing at least 20% by volume of compounds boiling above 340° C., said process consisting of the following steps:
- a) a step of hydrotreating said feedstock in the presence of hydrogen and at least one hydrotreating catalyst, at a temperature of 200° C. to 450° C., under a pressure of 2 and 25 MPa, at a space velocity of 0.1 to 6 h−1 and with an amount of hydrogen introduced such that the litre of hydrogen/litre of hydrocarbon volume ratio is 100 to 2000 Nl/l,
- b) a step of hydrocracking at least one portion of the effluent resulting from step a), the hydrocracking step b) taking place, in the presence of hydrogen and at least one hydrocracking catalyst, at a temperature of 250° C. to 480° C., under a pressure of 2 to 25 MPa, at a space velocity of 0.1 to 6 h−1 and with an amount of hydrogen introduced such that the litre of hydrogen/litre of hydrocarbon volume ratio is 80 to 2000 Nl/l,
- c) a step of high-pressure separation of the effluent resulting from hydrocracking step b) to produce at least a gaseous effluent and a liquid hydrocarbon effluent,
- d) a step of distilling at least one portion of the liquid hydrocarbon effluent resulting from step c) performed in at least one distillation column, from which step the following are drawn off:
- a gaseous fraction,
- at least one fraction comprising the converted hydrocarbon products having at least 80% by volume of products boiling at a temperature below 250° C., and
- an unconverted liquid fraction having at least 80% by volume of products having a boiling point above 175° C.,
- e) optionally a purging of at least one portion of said unconverted liquid fraction containing HPNAs, having at least 80% by volume of products having a boiling point above 175° C.,
- f) a second step of hydrocracking at least one portion of the unconverted liquid fraction having at least 80% by volume of products with a boiling point above 175° C., resulting from step d) and/or optional step e), said step f) being performed in the presence of hydrogen and of at least one second hydrocracking catalyst, at a temperature TR1 of 250° C. to 480° C., under a pressure of 2 to 25 MPa, at a space velocity of between 0.1 and 6 h−1 and with an amount of hydrogen introduced such that the litre of hydrogen/litre of hydrocarbon volume ratio is 80 to 2000 Nl/l,
- g) a step of hydrogenating at least one portion of the effluent resulting from step f) performed in the presence of hydrogen and of a hydrogenation catalyst, at a temperature TR2 of 150° C. to 470° C., under a pressure of 2 to 25 MPa, at a space velocity of 0.1 to 50 h−1 and with an amount of hydrogen introduced such that the litre of hydrogen/litre of hydrocarbon volume ratio is 100 to 4000 Nl/l, said hydrogenation catalyst comprising at least one metal from group VIII chosen from nickel, cobalt, iron, palladium, platinum, rhodium, ruthenium, osmium and iridium alone or as a mixture and not containing any metal from group VIB and a support chosen from refractory oxide supports, and in which the temperature TR2 is at least 10° C. below the temperature TR1,
- h) a step of high-pressure separation of the effluent resulting from the hydrogenation step g) to produce at least a gaseous effluent and a liquid hydrocarbon effluent, and
- i) recycling, into said distillation step d), at least one portion of the liquid hydrocarbon effluent resulting from step h).
9 more elements
Dependencies are inferred from the claim text.