Methods and systems for the conversion of crude oil to petrochemical products
Methods for processing a crude oil feedstock include introducing a crude oil stream to a reactive distillation unit to remove conradson carbon and metals from the crude oil stream and generate a distillate stream having a mean boiling point distribution less than the crude oil stream and passing the distillate stream in a gaseous form in a continuous manner and without further processing to a catalytic cracking reactor operating at a temperature of 300° C. to 800° C. with a cracking catalyst disposed therein that cracks the distillate stream to form a petrochemical product stream including light olefins and BTX.
1 . A method for processing a crude oil feedstock, the method comprising:
introducing a crude oil stream to a reactive distillation unit combining cracking and distillation of the crude oil stream in a single apparatus to remove conradson carbon and metals from the crude oil stream and generate a distillate stream having a mean boiling point distribution less than the crude oil stream, a light gas stream consisting of C1-C4 hydrocarbons, a heavy liquid fraction comprising atmospheric residue formed from hydrocarbons having a boiling point of 400° C. or greater, and coke, wherein a residence time of the crude oil stream in the reactive distillation unit is 1 minute to 60 minutes, where the reactive distillation unit comprises solid particles disposed within the reactive distillation unit to preferentially capture the conradson carbon and metals in the crude oil stream and the coke generated in the reactive distillation unit; and
passing the distillate stream in a gaseous form in a continuous manner and without further processing to a catalytic cracking reactor with a cracking catalyst disposed therein that cracks the distillate stream to form a petrochemical product stream comprising light olefins and BTX, a light gas effluent consisting of hydrogen and C1-C4 alkanes, and an unconverted distillate stream comprising the remainder of the distillate stream passed to the catalytic cracking reactor unit, wherein the catalytic cracking reactor operates at a temperature of 300° C. to 800° C.
2 . The method of claim 1 , where the light gas stream is passed concurrently with the distillate stream to the catalytic cracking reactor.
3 . The method of claim 1 , where light olefins and BTX forming the petrochemical product stream comprise one or more of ethylene, propylene, butenes, benzene, toluene, and xylenes.
4 . The method of claim 1 , where the reactive distillation unit is operated at a temperature in the range of 300° C. to 500° C.
5 . The method of claim 1 , where the reactive distillation unit is operated at a pressure in the range of 1 to 20 bars absolute.
6 . The method of claim 1 , where the solid particles comprise one or more of kaolin, silica, alumina, silica alumina, silica-alumina doped with phosphorus, magnesium oxide, titania, zirconia, alumina-magnesia spinel, hydrotalcite, and molecular sieves.
7 . The method of claim 1 , where the solid particles are removed continuously or periodically from the reactive distillation unit with the heavy liquid fraction.
8 . The method of claim 1 , where the catalytic cracking reactor is a fixed bed reactor.
9 . The method of claim 1 , where the catalytic cracking reactor is operated at pressure in the range of 0.5 to 10 bars absolute.
10 . The method of claim 1 , where an inert gas is fed to the catalytic cracking reactor.
11 . The method of claim 10 , where the inert gas is water vapor.
12 . The method of claim 1 , where the cracking catalyst is a zeolite or a mixture of zeolites.
13 . The method of claim 12 , where the cracking catalyst comprises a blend of large pore zeolite and medium pore zeolite.
14 . The method of claim 12 , where the cracking catalyst comprises Y-zeolite and ZSM-5 at a ratio of 90:10 to 50:50 by weight.
15 . The method of claim 1 , where the catalytic cracking reactor comprises one or more first catalyst beds comprising a large pore zeolite followed by one or more second catalyst beds comprising a medium pore zeolite.
16 . The method of claim 15 , where the first catalyst beds and the second catalyst beds are heated at different temperatures.
17 . The method of claim 16 , where the first catalyst beds are heated at a temperature in the range of 400° C. to 650° C. and the second catalyst beds are heated at a temperature in the range of 500° C. to 750° C.
18 . The method of claim 1 , where the heavy liquid fraction is recycled back to the reactive distillation unit to extinction.
19 . The method of claim 1 , where the unconverted distillate stream is recycled back to the catalytic cracking reactor for further processing.