Ebullated or hybrid ebullated-bed hydroconversion of a feedstock comprising a fraction of plastic pyrolysis oil and/or solid recovery fuels

Abstract

The present invention relative to a process for the hydroconversion of a feedstock including a fraction of less than 50% by weight of plastic and/or SRF pyrolysis oil ( 102 ) and a heavy hydrocarbon fraction ( 101 ) containing a portion of at least 50% by weight with a boiling point of at least 300° C. and containing sulfur and nitrogen. The hydroconversion uses one or more ebullated bed or hybrid ebullated-entrained bed reactors ( 20 ), and preferably two successive hydroconversion steps. The process according to the invention allows the production of higher-quality, lower-boiling materials, for example for the production of fuels or chemical compounds for the petrochemical industry, with improved yields of certain cuts and while allowing facilitated processing of the hydroconverted products in downstream steps such as fixed-bed hydrotreatment and while maintaining good stability of the unconverted fraction.

1 . A process for the hydroconversion of a feedstock comprising a plastic and/or solid recovered fuel pyrolysis oil fraction ( 102 ) and a fossil-based heavy hydrocarbon fraction ( 101 ) containing a portion of at least 50% by weight with a boiling point of at least 300° C. and containing sulfur and nitrogen, said pyrolysis oil fraction ( 102 ) constituting less than 50% by weight of said feedstock, said process comprising:
 (a) conditioning and introducing said feedstock into a first hydroconversion section ( 20 ) including at least a first ebullated bed or hybrid ebullated-entrained bed hydroconversion reactor comprising a first porous supported hydroconversion catalyst; 
 (b) a first step of hydroconverting said feedstock in the presence of hydrogen in said first hydroconversion section ( 20 ) to obtain a first hydroconverted effluent ( 105 ); 
 (c) optionally, a step of separating part or all of said first effluent resulting from step (b), to form at least one heavy cut boiling predominantly at a temperature greater than or equal to 350° C.; 
 (d) optionally, a second hydroconversion step in a second hydroconversion section including at least a second ebullated bed or hybrid ebullated-entrained bed hydroconversion reactor of part or all of said first effluent resulting from step (b) or optionally of said heavy cut resulting from step (c), said second hydroconversion reactor comprising a second porous supported catalyst and operating in the presence of hydrogen, to produce a second hydroconverted effluent; 
 step (b) and optional step (d) being performed at an absolute pressure of between 2 MPa and 38 MPa, at a temperature of between 300° C. and 550° C., at an hourly space velocity of between 0.05 h −1  and 10 h −1 , and with an amount of hydrogen of between 50 Nm 3 /m 3  and 5000 Nm 3 /m 3 ; and 
 (e) a step of fractionating all or some of said first hydroconverted effluent from step (b) or of said second hydroconverted effluent from step (d), in a fractionation section ( 30 ), to produce at least one heavy liquid product ( 106   b ) which boils predominantly at a temperature greater than or equal to 350° C., said heavy liquid product containing a residual fraction boiling at a temperature greater than or equal to 540° C. 
 
     
     
         2 . The process as claimed in  claim 1 , wherein, in step (a), the pyrolysis oil fraction ( 102 ) and the heavy hydrocarbon fraction ( 101 ) of the feedstock are premixed before being introduced into said at least one first hydroconversion reactor of the first hydroconversion section ( 20 ). 
     
     
         3 . The process as claimed in  claim 1 , wherein, in step (a), the pyrolysis oil fraction ( 102 ) of the feedstock is introduced separately from the heavy hydrocarbon fraction ( 101 ) into said at least one first hydroconversion reactor of the first hydroconversion section ( 20 ). 
     
     
         4 . The process as claimed in  claim 1 , wherein step (a) includes a step of preheating said heavy hydrocarbon fraction ( 101 ), and optionally a step of preheating the pyrolysis oil fraction ( 102 ), before the feedstock is introduced into the first hydroconversion reactor of the first hydroconversion section ( 20 ). 
     
     
         5 . The process as claimed in  claim 1 , wherein the pyrolysis oil fraction ( 102 ) constitutes between 1% and 45% by weight of said feedstock. 
     
     
         6 . The process as claimed in  claim 1 , wherein the feedstock is constituted of said of pyrolysis oil fraction ( 102 ) and of said heavy hydrocarbon fraction ( 101 ), said pyrolysis oil fraction ( 102 ) constituting between 1% and 45% by weight of said feedstock and the heavy hydrocarbon fraction ( 101 ) constituting between 55% and 99% by weight, of the feedstock. 
     
     
         7 . The process as claimed  claim 1 , wherein the pyrolysis oil fraction ( 102 ) is a plastic pyrolysis oil. 
     
     
         8 . The process as claimed in  claim 1 , wherein the heavy hydrocarbon fraction ( 101 ) is chosen from the group consisting of a crude oil, a topped crude oil, an atmospheric residue or a vacuum residue resulting from the atmospheric and/or vacuum distillation of a crude oil or of an effluent originating from a thermal conversion, hydrotreating, hydrocracking or hydroconversion unit, an aromatic cut extracted from a unit for the production of lubricants, a deasphalted oil resulting from a deasphalting unit, an asphalt resulting from a deasphalting unit, a residual fraction resulting from direct coal liquefaction, a vacuum distillate resulting from direct coal liquefaction, and mixtures thereof. 
     
     
         9 . The process as claimed in  claim 8 , wherein the heavy hydrocarbon fraction ( 101 ) is a vacuum residue. 
     
     
         10 . The process as claimed in  claim 1 , wherein said process includes separation step (c) of separating part, or all, of the first hydroconverted effluent ( 105 ) obtained from step (b) to produce at least the heavy cut boiling predominantly at a temperature greater than or equal to 350° C., and includes the second step (d) of hydroconverting said heavy cut. 
     
     
         11 . The process as claimed in  claim 1 , wherein the hydroconversion reactor(s) of the first hydroconversion section ( 20 ) in step (b), and optionally in hydroconversion step (d), are hybrid ebullated-entrained bed reactors, said process also including a step of introducing a catalyst precursor ( 104 ) into the feedstock prior to injection of said feedstock into said at least one first hybrid ebullated-entrained bed reactor of the first hydroconversion section ( 20 ), in such a way that a colloidal or molecular catalyst is formed when said feedstock reacts with sulfur. 
     
     
         12 . The process as claimed in  claim 1 , wherein the first hydroconversion catalyst, and optionally the second hydroconversion catalyst, contains at least one non-noble group VIII metal chosen from nickel and cobalt, and at least one group VIB metal chosen from molybdenum and tungsten, and including an amorphous support. 
     
     
         13 . The process as claimed in  claim 1 , wherein step (b) and the optional step (d) are performed at a temperature of between 405° C. and 450° C. 
     
     
         14 . The process as claimed in  claim 1 , wherein said process includes separation step (c) and separation step (c) is performed in a separation section, and in which said separation section and/or the fractionation section ( 30 ) in step (e) include means for washing at least one separated cut by contact with an aqueous solution. 
     
     
         15 . The process as claimed in  claim 1 , further comprising a step (f) of further processing the heavy liquid product ( 106   b ) and/or of the other product(s) from fractionation step (e), said step (f) comprising at least one step chosen from the list consisting of hydrotreating, steam cracking, fluidized bed catalytic cracking, hydrocracking, deasphalting, lubricant oil extraction, and preferably a fixed-bed hydrotreatment step (f2) in a hydrotreatment section, said hydrotreatment section preferably comprising at least one fixed-bed reactor containing n catalytic beds, n being an integer greater than or equal to 1, each comprising at least one hydrotreatment catalyst, said hydrotreatment section being fed with at least a portion of a liquid product from step e) and a gaseous stream comprising hydrogen, to obtain a hydrotreated effluent. 
     
     
         16 . A product obtained via the process as claimed in  claim 1 . 
     
     
         17 . The hydroconverted effluent as claimed in  claim 16 , obtained on conclusion of the first hydroconversion step (b) or of the second hydroconversion step (d), and including a liquid part comprising, relative to the total weight of said liquid part of said effluent, a silicon content of less than or equal to 5 ppm by weight, and/or a chlorine element content of less than or equal to 10 ppm by weight. 
     
     
         18 . The process as claimed in  claim 1 , wherein step (a) includes a step of preheating said heavy hydrocarbon fraction ( 101 ) to a temperature of between 280° C. and 450° C., and optionally a step of preheating the pyrolysis oil fraction ( 102 ), before the feedstock is introduced into the first hydroconversion reactor of the first hydroconversion section ( 20 ). 
     
     
         19 . The process as claimed in  claim 1 , wherein the pyrolysis oil fraction ( 102 ) constitutes between 2% and 30% by weight of said feedstock. 
     
     
         20 . The process as claimed in  claim 1 , in which the feedstock is constituted of said of pyrolysis oil fraction ( 102 ) and of said heavy hydrocarbon fraction ( 101 ), said pyrolysis oil fraction ( 102 ) constituting between 2% and 30% by weight of said feedstock and the heavy hydrocarbon fraction ( 101 ) between 70% and 98% by weight of the feedstock.