Recovery of crude cuts utilizing c4 olefins and catalytic cracking of the combined crude cuts and c4 olefins

Abstract

A process for separating crudes and wide boiling hydrocarbon mixtures into intermediate fractions fed to a downstream catalytic cracking system (122) including feeding a hydrocarbon mixture (100) into a heating unit (106) and heating the hydrocarbon mixture; feeding a heated hydrocarbon mixture (101) and a stripping medium (102) to a stripper (110); separating the heated hydrocarbon mixture into a stripper overhead effluent (114) including intermediate fractions and the stripping medium, and a stripper bottoms effluent (116). The process including feeding the stripping medium and the intermediate fractions to a catalytic cracking system; contacting the intermediate fractions and the stripping medium with a cracking catalyst in the catalytic cracking system, producing an intermediate cracked product (124); separating the intermediate cracked product into distillate fractions including a recycle stripping medium (130) and a cracked product (128); and recovering the recycle stripping medium.

Description

PATENT APPLICATION ATTORNEY DOCKET NO. 17421-256WO1 CLIENT REFERENCE NO 2024LCC008-WO RECOVERY OF CRUDE CUTS UTILIZING C4 OLEFINS AND CATALYTIC CRACKING OF THE COMBINED CRUDE CUTS ANDC4 OLEFINSBACKGROUND

[0001] Recently, the production of light olefins via fluid catalytic cracking (FCC) processes has been considered one of the most attractive commercial propositions of refining. There is an ever-increasing demand for petrochemical building blocks such as propylene, ethylene, and aromatics (benzene, toluene, xylenes, etc.) while traditional products such as gasoline have decreased in demand. Therefore, increasing olefins production, including propylene production from crude is of particular interest, due to the high value of propylene in comparison to crude.

[0002] Conventionally, refineries have utilized crude distillation technology including vacuum distillation and atmospheric distillation. These technologies require a large footprint, high capital costs, and high operating costs.

[0003] One possible solution is to replace some of the conventionally required cascading distillation columns with a heating unit and a stripper to strip out the desired, or intermediate, fractions from the crude prior to catalytic cracking. Stripping crude with a low molecular weight stripping medium lightens the products sent to catalytic cracking, and thereby increases the olefins production from the downstream catalytic cracker. In the past, operators have utilized hydrogen and methane as a stripping medium.SUMMARY OF THE CLAIMED EMBODIMENTS

[0004] This summary is provided to introduce a selection of concepts that are further described below in the detailed description. This summary is not intended to identify key or essential features of the claimed subject matter, nor is it intended to be used as an aid in limiting the scope of the claimed subject matter.

[0005] In one aspect, embodiments disclosed herein relate to a process for separating whole crudes and other wide boiling hydrocarbon mixtures into one or more intermediate fractions fed to a downstream catalytic cracking system and thereby maximizing olefins and aromatics production including: feeding a hydrocarbon mixture including the whole crude into a heating unit and heating the hydrocarbon mixture toPATENT APPLICATION ATTORNEY DOCKET NO. 17421-256WO1 CLIENT REFERENCE NO 2024LCC008-WO produce a heated hydrocarbon mixture; feeding the heated hydrocarbon mixture and a stripping medium to a stripper; separating the heated hydrocarbon mixture into a stripper overhead effluent including one or more intermediate fractions and a 400°C- cut and the stripping medium, and a stripper bottoms effluent including a residue fraction; feeding the stripping medium and the one or more intermediate fractions to a catalytic cracking system; contacting the one or more intermediate fractions and the stripping medium with a cracking catalyst in the catalytic cracking system, producing an intermediate cracked product; feeding the cracked product to a distillation column and separating the intermediate cracked product into one or more distillate fractions including a recycle stripping medium and a cracked product; and recovering the recycle stripping medium.

[0006] In another aspect, embodiments disclosed herein relate to a system for separating whole crudes and other wide boiling hydrocarbon mixtures into one or more intermediate fractions fed to a downstream catalytic cracking system and thereby maximizing olefins and aromatics production including: a heating unit for heating the hydrocarbon mixture into a heated hydrocarbon mixture; a stripper including a stripping medium inlet, a hydrocarbon inlet, an overhead vapor outlet, and a bottoms outlet, where the heated hydrocarbon mixture is fed to the hydrocarbon inlet and a stripping medium is fed to the stripping medium inlet and a stripper overhead effluent including one or more intermediate fractions and the stripping medium is recovered from the overhead vapor outlet and a residue fraction is recovered from the bottoms outlet; a catalytic cracking system for contacting the stripper overhead effluent with a cracking catalyst to produce an intennediate cracked product; and a distillation column for separating the intermediate cracked product into one or more distillate fractions including a recycle stripping medium and a cracked product.

[0007] Other aspects and advantages will be apparent from the following description and the appended claims.BRIEF DESCRIPTION OF DRAWINGS

[0008] The figure illustrates a simplified process flow diagram of a system for converting whole crudes and / or hydrocarbon mixtures into olefins and aromatics according to the embodiments herein.DETAILED DESCRIPTIONPATENT APPLICATION ATTORNEY DOCKET NO. 17421-256WO1 CLIENT REFERENCE NO 2024LCC008-WO

[0009] The increased demand for high value chemicals and the opportunity to increase propylene production from crude while avoiding high-cost distillation units may be solved by systems and processes of heating whole crudes and wide boiling hydrocarbon mixtures in a heating unit, separating the hydrocarbon mixture in a stripper, and cracking the intermediate fractions in a catalytic cracking system. The stripper utilizes a stripping medium, as defined further below, that is a hydrocarbon or hydrocarbon mixture rich in C4 olefins, or a mixture of hydrocarbons including C4 olefins and steam, to produce a stripper overhead effluent including separated components of the hydrocarbon mixture, C4 olefins, and steam. The stripper overhead effluent may be cracked in a downstream catalytic cracking system. The increased proportion of lighter components separated from the crude and additional C4 olefins fed as feed into the catalytic cracking system downstream may thereby increase the production of high value olefins from the catalytic cracking system

[0010] Embodiments herein relate to processes and systems that receive whole crudes and other wide boiling hydrocarbon mixtures as feed and produce chemicals, such as light olefins and diolefins (ethylene, propylene, butadiene, and / or butenes) and aromatics. Embodiments herein are directed towards processes and systems for making olefins and aromatics by catalytic cracking of a stripped whole crude and other wide boiling hydrocarbon mixtures.

[0011] Hydrocarbon mixtures useful in embodiments disclosed herein may include various hydrocarbon mixtures having a boiling point range where the end boiling point of the mixture may be from between 200°C and 1100 °C, such as a lower limit of 200, 250, 300, 350, 400, 450, 500, 550, 600, 650, 700, 750, 800, 850, 900, 950, 1000°C, to an upper limit of 250, 300. 350, 400, 450, 500, 550, 600, 650. 700, 750, 800, 850, 900, 950, 1000 and 1100 °C, where any lower limit can be combined with any mathematically compatible upper limit. Boiling point as defined herein may include one measured using ASTM D86 or ASTM D2887, or it may be a True Boiling Point (TBP) analysis according to ASTM D2892.

[0012] In some embodiments, a whole crude or wide boiling hydrocarbon mixture may be separated first into two cuts, including a light hydrocarbon fraction and a medium / heavy hydrocarbon fraction, such as a 200 °C- cut and a 200 °C+ cut, or a 250 °C- cut and a 250 °C+ cut. In this embodiment, either the 200 °C- or the 250 °C- cutPATENT APPLICATION ATTORNEY DOCKET NO. 17421-256WO1 CLIENT REFERENCE NO 2024LCC008-WO may be relatively clean, meaning the stripper overhead effluent may not have any substantial amount (>5 wt% as used herein) of compounds boiling above the intended boiling temperature target. For example, the 200°C- or the 250°C- cut may not have any substantial amount (z'.e., >5 wt%) of hydrocarbon compounds boiling above 200°C or 250°C respectively. Likewise, the 200 °C+ cut or the 250 °C+ cut may be relatively clean, meaning the stripper bottoms effluent may not have any substantial amount (>5 wt% as used herein) of compounds boiling below the intended boiling temperature target. For example, the 200 °C+ cut or the 250°C+ cut may not have any substantial amount (i.e., >5 wt%) of hydrocarbon compounds boiling below 200 °C or 250°C, respectively.

[0013] Other cut points may also be used, such as 150 °C, 160 °C, 170 °C, 180 °C, 190 °C, 210 °C, 220 °C, 230 °C, 240 °C, 260 °C, or 270 °C, thereby defining the boiling point of hydrocarbons contained in the light or medium / heavy cuts. While other cut points may be used, embodiments herein will be described with respect to a 250 °C cut point.

[0014] In this embodiment, the separation may be achieved by heating the whole crude or wide boiling hydrocarbon mixture and then separating the resulting heated whole crude or heated wide boiling hydrocarbon mixture in a first stage stripper. The first stage stripper may utilize any stripping medium including but not limited to steam. While the 250 °C- cut may be cracked in a downstream steam cracker for lighter fractions to be recovered downstream, the 250 °C+ cut may be fed to a heating unit.

[0015] In one or more embodiments, the hydrocarbon mixture, including the 250 °C+ cut, may be fed to a heating unit, producing a heated hydrocarbon mixture. The heating unit may be any combination of one or more fired heaters, heat exchangers, or crossexchangers recovering waste heat from any associated refinery or olefins operation. The heating unit may increase the partial pressure of the hydrocarbon mixture, thereby reducing the energy required to separate the hydrocarbon mixture. For example, less stripping medium may be required in a downstream stripper. The hydrocarbon mixture may be heated in the heating unit to a temperature between 150 and 400 °C, such as a lower limit of 150, 200, 250, 300 and 350 °C, to an upper limit of 200, 250, 300, 350, and 400 °C, where any lower limit can be mathematically combined with any upperPATENT APPLICATION ATTORNEY DOCKET NO. 17421-256WO1 CLIENT REFERENCE NO 2024LCC008-WO limit. In some embodiments, the heating unit may include one or more pump-around streams back to the first stage stripper.

[0016] In one or more embodiments, the heated hydrocarbon mixture may be contacted in a stripper with a stripping medium injected proximate a bottom of the stripper. The stripping medium may be enriched with one or more of any isomer of butene including 1 -butene, cis-2-butene, trans-2-butene, and isobutylene (collectively, “C4 olefins”). In some embodiments, the stripping medium may be a stream from any associated olefins or refinery operation, enriched with one or more of any isomer of butene including 1 - butene, cis-2-butene, trans-2-butene, isobutylene, among other hydrocarbons. In some embodiments, the stripping medium may include C4-C10 hydrocarbons in addition to the C4 olefins.

[0017] In some embodiments, before being fed to the stripper, the stripping medium may be superheated to a temperature between 160 and 420 °C, such as a lower limit of 160, 200, 250, 300, 350, and 400 °C, to an upper limit of 200, 250, 300, 350, 400, and 420 °C, where any lower limit may be mathematically combined with any upper limit. In one or more embodiments, the normal boiling point of the stripping medium may be between -30 and 100 °C, such as a lower limit of -30, 0, 10, 20, 30, 40, 50, 60, 70, 80, 90°C, to an upper limit of 0, 10, 20, 30, 40, 50, 60, 70, 80, 90, and 100°C, where any lower limit may be mathematically combined with any upper limit. The stripping medium may be vaporized and superheated in any type of heat exchanger. In some embodiments, the heat exchanger may be a heat exchanger utilizing high pressure steam, a cross-exchanger recovering waste heat from any associated refinery or olefins operation, or a fired heater. By heating the stripping medium, the heat exchanger may increase the partial pressure of the stripping medium and allow a higher concentration of the intermediate fractions to flow in the stripper overhead effluent.

[0018] In some embodiments, the stripping medium may include low or medium pressure superheated steam injected at a temperature between 160 and 420 °C, such as a lower limit of 160, 200, 250, 300, 350, and 400 °C, to an upper limit of 200, 250, 300, 350, 400, and 420 °C, where any lower limit may be mathematically combined with any upper limit. The low or medium pressure superheated steam may be any pressure, related to the selected temperature, between 2 and 50 bar, such as a lower limit of 2, 10,PATENT APPLICATION ATTORNEY DOCKET NO. 17421-256WO1 CLIENT REFERENCE NO 2024LCC008-WO 20, 30, and 40 bar, to an upper limit of 10, 20, 30, 40, and 50 bar, where any lower limit may be mathematically combined with any upper limit.

[0019] The required flow rate of stripping medium may vary based on the desired selection of intermediate fractions to be fed to the downstream catalytic cracking unit, the concentration of the C4 olefins in the stripping medium, and the physical properties of the steam (if used). The required molar ratio of steam to C4 olefins may be between 0.5:1 and 3:1 in some embodiments. The C4 olefins included in the stripping medium may be from one or more locations within a refinery or olefins operation. In some embodiments, some of the stripping medium may be imported from outside of boundary limits (OSBL) of the plant or processing unit. Finally, the C4 olefins included in the stripping medium may additionally be fed from the downstream catalytic cracking system. As the catalytic cracking system receives the intermediate fractions and the stripping medium including C4 olefins, it may generate C4 olefins to be recycled back into the stripper as the stripping medium.

[0020] In some embodiments where the stripping medium includes steam, the steam may be injected proximate a bottom of the stripper in order to prevent or reduce the flow of C4 olefins from exiting the stripper via the stripper bottoms effluent with heavier and less valuable residue fraction. Thus, injecting a stripping medium including steam proximate a bottom of the stripper may allow for more C4 olefins to exit the top of the stripper to the catalytic cracking unit, thereby increasing the production of valuable olefins, including propylene. Finally, the addition of steam to the stripper may reduce the steam required downstream in the catalytic cracking system. The addition of steam to the stripper may also dilute the downstream feed to the catalytic cracking system, reducing the partial pressure, thereby enabling higher olefin production, yield, and conversion. In order to maximize the operational benefit of injecting steam proximate a bottom of the stripper, the flow rate of steam to the stripper must not exceed the total amount required by the downstream catalytic cracking system. Finally, utilizing stripping medium including a mixture of C4 olefins and C4 hydrocarbons may allow for a reduced riser length in the catalytic cracking system. Since the feed to the riser would be in vapor phase, the riser may be shorter, while still achieving the same conversion when compared to liquid phase feed injection. Further, injecting vapor phase feed may allow for reduced coke make-up to satisfy the heat balancePATENT APPLICATION ATTORNEY DOCKET NO. 17421-256WO1 CLIENT REFERENCE NO 2024LCC008-WO requirements of the catalytic cracking system when compared to liquid feed. Additionally, reduction of the coke make-up may allow for reduced carbon emissions over the operational lifecycle of the catalytic cracking system.

[0021] The stripper may be equipped with any number of trays including, such as between 4 and 25 trays, for example, suitable to achieve the desired, or intermediate, fractions. The stripper may be equipped with any type of tray including but not limited to sieve trays, valve trays, and any type of tray that may be adequate for operation in fouling service. In some embodiments, packing near the top section of the stripper may be required for de-entrainment of vapor leaving the stripper. In one or more embodiments, a combination of trays and packing may be used to achieve the desired, or intermediate, fractions.

[0022] In one or more embodiments, the stripper operating pressure may be between 1.5 and 6.5 kg / cm2-g (kscg), such as a lower limit of 1.5, 2, 2.5, 3, 3.5, 4, 4.5, 5, 5.5, and 6 kscg, to an upper limit of 2, 2.5, 3, 3.5, 4, 4.5, 5, 5.5, 6, and 6.5 kscg, where any lower limit may be mathematically combined with any upper limit. The stripper operating temperatures may be in a range from 100 to 420 °C, such as a lower limit of 100, 150, 200, 250, 300, 350, and 400 °C, to an upper limit of 150, 200, 250, 300, 350, 400, and 420 °C, where any lower limit may be mathematically combined with any upper limit.

[0023] The heated hydrocarbon mixture, including the 250 °C+ cut, may be contacted with a stripping medium including steam and C4 olefins and separated into a stripper bottoms effluent and a stripper overhead effluent. The stripper bottoms effluent may include a residue fraction with hydrocarbons having a boiling point above 300 °C, such as between 300 and 450 °C, such as between 350 and 450 °C, or between 350 and 400 °C. Additionally, the stripper bottoms effluent may include a residue fraction containing hydrocarbons having a boiling point greater than 450 °C. Thus, the cut point between the residue fraction from the stripper bottoms effluent and the vaporized hydrocarbons recovered with the stripper overhead effluent may be between 300 and 450 °C, or it may be greater than 450 °C. In one or more embodiments, the stripper bottoms effluent may have a 400°C+ cut, where the stripper bottoms effluent “cut” may be relatively clean, meaning the stripper bottoms effluent may not have any substantial amount (>5 wt% as used herein) of compounds boiling below the intended boilingPATENT APPLICATION ATTORNEY DOCKET NO. 17421-256WO1 CLIENT REFERENCE NO 2024LCC008-WO temperature target. For example, a 400°C+ cut may not have any substantial amount of hydrocarbon compounds boiling below 400°C (z.e., >5 wt%).

[0024] The stripper overhead effluent may include one or more intermediate fractions and may include hydrocarbons having a boiling point between 10 and 400 °C, such as a lower limit of -10, 0, 50, 100, 150, 200, 250, 300, and 350 °C, to an upper limit of 0, 50, 100, 150, 200, 250, 300, 350, and 400 °C, where any lower limit may be mathematically combined with any upper limit. The one or more intermediate fractions may include but not be limited to hydrocarbons with boiling points as low as any isomer of pentane, pentene, or naphtha. In one or more embodiments, the stripper overhead effluent may be a 400°C- cut, where the stripper overhead effluent “cut” may be relatively clean, meaning the stripper overhead effluent may not have any substantial amount (>5 wt% as used herein) of compounds boiling above the intended boiling temperature target. For example, a 400°C- cut may not have any substantial amount (z.e., >5 wt%) of hydrocarbon compounds boiling above 400°C.

[0025] In other embodiments, the intended “cut” temperatures noted above with respect to the 250°C+ cut, 250°C- cut, 400°C+ cut, and the 400°C- cut may be a 95% boiling point temperature, or in other embodiments as an 85% boiling point temperature, such as may be measured using ASTM D86 or ASTM D2887, or a True Boiling Point (TBP) analysis according to ASTM D2892, for example, and ASTM D7169 for heavy streams, such as those boiling above 400°C. In such embodiments, there may be up to 15 wt% of compounds boiling above the indicated “cut” point temperature as applicable.

[0026] The relatively low molecular weight of C4 olefins as compared to the average molecular weight of whole crudes and hydrocarbon mixtures renders C4 olefins a suitable stripping medium. Depending on the composition of the selected stripping medium and the intermediate fractions downstream, the stripper may be able to strip hydrocarbons with boiling points between 150 and 400 °C, such as a lower limit of 150, 200, 250, 300, and 350 °C, to an upper limit of 200, 250 °C, 300, 350, and 400 °C, where any lower limit may be mathematically combined with any upper limit.

[0027] Additionally, depending on the feed composition of the heated hydrocarbon mixture fed to the stripper, the 250 C+ cut, the selection of intermediate fractions feeding the downstream catalytic cracking system, the stripper overhead effluent may include hydrocarbons having a boiling point below 350°C, below 375°C, below 400°CPATENT APPLICATION ATTORNEY DOCKET NO. 17421-256WO1 CLIENT REFERENCE NO 2024LCC008-WO (e.g., a 400°C- cut), below 425°C, and below 450°C. Likewise, the stripper bottoms effluent may include hydrocarbons having a boiling point above 350°C, above 375° C, above 400°C (e.g., a 400°C+ cut), above 425°C, and above 450°C. Embodiments herein also contemplate the stripper overhead effluent and stripper bottoms effluent having hydrocarbons with boiling points intermediate to the aforementioned respective temperatures.

[0028] Gases with a lower molecular weight than C4 olefins such as hydrogen and methane, while more effective at stripping even lighter components from the whole crudes and hydrocarbon mixtures, require a more extensive downstream recovery and larger equipment footprint than a C4 olefins stripping medium. Thus, while the molecular weight of C4 olefins is not as low as hydrogen, methane or other light gases, making C4 olefins less preferred as a stripping medium, the use of C4 olefins in the stripping medium may enable the avoidance of extensive downstream recovery equipment including but not limited to reflux drums and condensers. Additionally, the stripping medium including C4 olefins may be co-cracked in the catalytic cracking system and thereby increase propylene production from the catalytic cracking system. Thus, C4 olefins may provide a dual function as both a stripping medium and as a feedstock to produce more intermediate fractions in the stripper overhead effluent.

[0029] After the heated hydrocarbon mixture is processed in the stripper, the stripper overhead effluent may be catalytically cracked with a suitable catalyst in a catalytic cracking system into an intermediate cracked product. In one or more embodiments, the intermediate cracked product may include methane, ethane, ethylene, propane, propylene, any isomers of butene, any aromatics, and relatively heavier components. The catalytic cracking system may be any system which may be capable of cracking the stripper overhead effluent. This may include but is not limited to a fluid catalytic cracker or a single regenerator dual catalyst (SRDC) reactor system. The fluid catalytic cracker (FCC) may include a riser reactor, a fluid bed cracker, one or more packed bed reactors, or a fixed bed reactor, or combinations thereof. There are many suitable catalysts commercially available for catalytic cracking including but not limited to zeolite used for heavy feeds and ZSM-5 for lighter feeds and preserving lower olefins. Any catalyst that is suitable for catalytically cracking whole crudes and hydrocarbon mixtures may be used.PATENT APPLICATION ATTORNEY DOCKET NO. 17421-256WO1 CLIENT REFERENCE NO 2024LCC008-WO

[0030] Finally, the intermediate cracked product may be separated into one or more distillate fractions, including the stripping medium, and a cracked product. In one or more embodiments, the stripping medium separated from the intermediate cracked product may include a mixture of C4 olefins and other C4 hydrocarbons (“C4 olefins stripping medium”). The separation may occur in a distillation column or a series of distillation columns located inside a downstream gas plant or any other associated refinery or olefins operation. The stripping medium may then be recycled back to the stripper from the distillation column as recycle stripping medium.

[0031] In some embodiments, the stripper overhead effluent optionally may be partially condensed in a partial condenser and produce a vapor stripper overhead effluent and a liquid stripper overhead effluent. The partial condenser may be employed to maintain a particular range of intermediate fractions to be fed to the catalytic cracking system. Additionally, the reflux stream on the partial condenser may function to minimize the carryover of undesirable heavy molecules to the catalytic cracking system.

[0032] In some embodiments, the partial condenser may utilize a cooling medium to indirectly condense at least a portion of the stripper overhead effluent into liquid stripper overhead effluent. The liquid stripper overhead effluent may be fed back into the stripper as reflux. The remaining stripper overhead effluent that is not condensed by the cooling medium may be recovered as a vapor stripper overhead effluent. The vapor stripper overhead effluent may be fed to a catalytic cracking system. The vapor stripper overhead effluent may include one or more intermediate fractions, and may have a boiling point between -10 and 400 °C, such as a lower limit of -10, 0, 50, 100, 150, 200, 250, 300, and 350 °C, to an upper limit ofl50, 200, 250, 300, 350, and 400 °C, where any lower limit may be mathematically combined with any upper limit. In one or more embodiments, the vapor stripper overhead effluent may be a 400°C- cut.

[0033] Referring now to the Figure, a simplified process flow diagram of a system for converting whole crudes and hydrocarbon mixtures into olefins and aromatics according to embodiments disclosed herein is illustrated. The system includes a heating unit, a stripper, a catalytic cracking system, and a distillation column for maximizing the yield of light olefins including but not limited to propylene from whole crudes and hydrocarbon mixtures.PATENT APPLICATION ATTORNEY DOCKET NO. 17421-256WO1 CLIENT REFERENCE NO 2024LCC008-WO

[0034] The hydrocarbon mixture 100, which may include a 150 °C+ cut or a 250 °C+ cut, is injected into heating unit 106 to be heated to a temperature between 150 and 400 °C, prior to the introduction of the heated hydrocarbon mixture 101 into the stripper 110 proximate a top of the stripper at the hydrocarbon inlet. Although not shown in the figure, the heating unit may include one more pump-arounds to a first-stage stripper upstream to maximize heating recovery. Additionally, the heating unit 106 may include fired equipment or an electric heater. In either embodiment, after being heated to between 150 and 350 °C, the heated hydrocarbon mixture may be fed to a hydrocarbon inlet proximate a top of the stripper 110.

[0035] The stripping medium 102 may be heated in a heat exchanger 106 into a heated stripping medium 105 prior to introduction into the stripper 110. In one or more embodiments, the stripping medium 102 may be superheated to a vapor-phase heated stripping medium 105 between 160 and 420 °C. In some embodiments, only a portion of the stripping medium 102 may be heated in the heat exchanger 104. In other embodiments, all of the stripping medium 102 may be heated in the heat exchanger 104. While the heated stripping medium 105 is shown to be fed at the bottom of the stripper 110 at a stripping medium inlet, the feed location of the stripping medium 102 may vary depending on the boiling point of the hydrocarbon mixture 100, the stripping medium composition, and other operational factors.

[0036] Prior to being heated in the heat exchanger 104, the stripping medium 102 may be mixed with recycle stripping medium 130 from any location in an associated olefins or refinery operations downstream, or a downstream distillation column 126. Finally, in addition to the heated stripping medium 105, a steam stripping medium 108 may be introduced at a steam inlet proximate a bottom of the stripper to enhance the C4 olefins recovery in the stripper overhead effluent and to reduce the steam volume required in the operation of the downstream catalytic cracking system 122, or for use during startup operations.

[0037] The heated hydrocarbon mixture 101 may then be contacted with the heated stripping medium 105 and the steam stripping medium 108. The stripper 110 may separate the heated hydrocarbon mixture 101 into 114 stripper overhead effluent and a stripper bottoms effluent 116, including a residue recovered from the bottoms outlet. The stripper overhead effluent 114 may exit the stripper through the overhead vaporPATENT APPLICATION ATTORNEY DOCKET NO. 17421-256WO1 CLIENT REFERENCE NO 2024LCC008-WO outlet proximate the top of the stripper and may include one or more intermediate fractions and hydrocarbons with a boiling point between 150 and 400°C, such as a 400°C- cut point. The one or more intermediate fractions may include hydrocarbons with boiling points similar to C5 hydrocarbons. Thus, the stripper overhead effluent 114 may include the heated stripping medium 105, one or more intermediate fractions including C5 hydrocarbons, and the steam stripping medium 108. The stripper overhead effluent 114 may then be fed directly to the catalytic cracking system 122.

[0038] Optionally, all or a portion of the stripper overhead effluent 114 may be fed to a reflux drum 112 where a cooling medium may be used to partially condense the stripper overhead effluent 114 into a liquid stripper overhead effluent 118. The remaining fraction not condensed in the reflux drum 112 will be the vapor stripper overhead effluent 120, which may be fed to the catalytic cracking system 122. The vapor stripper overhead effluent 120 may include one or more intermediate fractions, and may have a boiling point between 150 and 400 °C, such as a 400°C- cut point.

[0039] The catalytic cracking system 122 may include a fluid catalytic cracker, a single regenerator dual catalyst (SRDC), or both. The catalytic cracking system may crack one or more intermediate fractions of the stripper overhead effluent 114, the vapor stripper overhead effluent 120, or any combination thereof into an intermediate cracked product 124. The intermediate cracked product 124, including hydrocarbons as light as methane, ethane, propane, ethylene, isomers of propylene, isomers of butene, heavy hydrocarbons and any aromatic, may then be fed to a distillation column 126, or series of distillation columns (not shown), flash drums, or combinations thereof (not shown). The distillation column 126 may separate the intermediate cracked product 124 into the recycle stripping medium 130 and a cracked product 128. Although not shown in the figure, the cracked product 128 may be collected further downstream or removed from the site at various collection points onsite or offsite. The recycle stripping medium 130 may be recycled and mixed with the stripping medium 102.

[0040] The above-described scheme may provide for a reduction in operating and fixed investment cost as compared to the conventional crude distillation and vacuum distillation units. Unlike lighter stripping mediums including predominately hydrogen and methane, the C4 olefins stripping medium provides the dual function of a stripping medium and a secondary reactant to be co-cracked in a downstream catalytic crackingPATENT APPLICATION ATTORNEY DOCKET NO. 17421-256WO1 CLIENT REFERENCE NO 2024LCC008-WO system. Since C4 olefins may be produced in the downstream catalytic cracking system, recovered downstream, and then recycled back into the stripper, any C4 olefins stripping medium may therefore be regenerative by mere operation of the process.

[0041] First, a regenerative stripping medium provides increased operational efficiency and reduced variable costs because less make-up stripping medium in the operation will be required. Second, the use of a regenerative stripping medium that can be both consumed and produced in the catalytic cracking system also prevents the need for extensive downstream equipment for the recovery of the stripping medium. The equipment required to recover stripping mediums of predominately hydrogen and methane may include one or more heat exchangers, reflux drums, effluent pumps, and recycle compressors. For such lighter gasses, condensers required to separate light gases from the stripper effluent will be much larger than condensers required by C4 olefins. Additionally, the use of the stripping mediums including predominately hydrogen and methane may impact the downstream catalytic cracking reaction chemistry and heat balance, and thereby not preferred.

[0042] Finally, it is to be understood that the configurations described above, along with the specific examples and uses are only illustrations of the application of the principles in the present invention. Numerous modifications and variants of the arrangements may be made by those skilled in the art without departing from the spirit and scope of the present disclosure and the appended claims are intended to include such modifications. Thus, while the present invention has been described above with particularity, it will be apparent to those of ordinary skill in the art that numerous modifications, including but not limited to, variations in assembly, size, materials, form, function, and operation may be used without departing from the principles and concepts set forth herein.

[0043] Unless defined otherwise, all technical and scientific terms used have the same meaning as commonly understood by one of ordinary skill in the art to which these systems, apparatuses, methods, processes and compositions belong.

[0044] The singular forms “a,” “an,” and “the” include plural referents, unless the context clearly dictates otherwise.PATENT APPLICATION ATTORNEY DOCKET NO. 17421-256WO1 CLIENT REFERENCE NO 2024LCC008-WO

[0045] As used here and in the appended claims, the words “comprise,” “has,” and “include” and all grammatical variations thereof are each intended to have an open, non-limiting meaning that does not exclude additional elements or steps.

[0046] “Optionally” means that the subsequently described event or circumstances may or may not occur. The description includes instances where the event or circumstance occurs and instances where it does not occur.

[0047] Ranges may be expressed as from one particular value to another particular value, inclusive. When such a range is expressed, it is to be understood that another embodiment is from the one particular value to the other particular value, along with all particular values and combinations thereof within the range.

[0048] While the disclosure includes a limited number of embodiments, those skilled in the art, having benefit of this disclosure, will appreciate that other embodiments may be devised which do not depart from the scope of the present disclosure. Accordingly, the scope should be limited only by the attached claims.

Claims

PATENT APPLICATION ATTORNEY DOCKET NO. 17421-256WO1 CLIENT REFERENCE NO 2024LCC008-WO CLAIMSWhat is claimed is:

1. A process for separating whole crudes and other wide boiling hydrocarbon mixtures into one or more intermediate fractions fed to a downstream catalytic cracking system and thereby maximizing olefins and aromatics production, the process comprising: feeding a hydrocarbon mixture comprising the whole crude or other wide boiling hydrocarbon mixtures into a heating unit and heating the hydrocarbon mixture to produce a heated hydrocarbon mixture;feeding the heated hydrocarbon mixture and a stripping medium to a stripper; separating the heated hydrocarbon mixture into a stripper overhead effluent comprising one or more intermediate fractions and a 400°C- cut and the stripping medium, and a stripper bottoms effluent comprising a residue fraction;feeding the stripping medium and the one or more intermediate fractions to a catalytic cracking system;contacting the one or more intermediate fractions and the stripping medium with a cracking catalyst in the catalytic cracking system, producing an intermediate cracked product;feeding the cracked product to a distillation column and separating the intermediate cracked product into one or more distillate fractions including a recycle stripping medium and a cracked product; andrecovering the recycle stripping medium.

2. The process of claim 1, wherein the stripping medium has a boiling point between - 30°C and 100°C.

3. The process of claim 1, wherein the stripper overhead effluent has a cut point between -10°C and 400°C.

4. The process of claim 1, wherein the one or more intermediate fractions has a cut point between 150°C and 400°C.

5. The process of claim 1, further comprising contacting the hydrocarbon mixture with a steam stripping medium in the stripper.

6. The process of claim 1, further comprising:partially condensing the stripper overhead effluent in a partial condenser, producing a vapor stripper overhead effluent and a liquid stripper overhead effluent; feeding the liquid stripper overhead effluent back into the stripper as a reflux; andPATENT APPLICATION ATTORNEY DOCKET NO. 17421-256WO1 CLIENT REFERENCE NO 2024LCC008-WO feeding the vapor stripper overhead effluent to the catalytic cracking system.

7. The process of claim 1, further comprising superheating the stripping medium to a temperature between 160 and 420 °C before being fed to the stripper.

8. The process of claim 1, wherein the hydrocarbon mixture is heated in the heating unit to a temperature between 150 and 400°C, thereby producing a heated hydrocarbon mixture.

9. The process of claim 7, wherein the hydrocarbon mixture is fed to the stripper at a pressure between 1.5 and 6.5 kscg.

10. A system for separating whole crudes and other wide boiling hydrocarbon mixtures into one or more intermediate fractions fed to a downstream catalytic cracking system and thereby maximizing olefins and aromatics production, the system comprising:a heating unit for heating the hydrocarbon mixture into a heated hydrocarbon mixture; a stripper comprising a stripping medium inlet, a hydrocarbon inlet, an overhead vapor outlet, and a bottoms outlet, wherein the heated hydrocarbon mixture is fed to the hydrocarbon inlet and a stripping medium is fed to the stripping medium inlet and a stripper overhead effluent including one or more intermediate fractions and the stripping medium is recovered from the overhead vapor outlet and a residue fraction is recovered from the bottoms outlet;a catalytic cracking system for contacting the stripper overhead effluent with a cracking catalyst to produce an intermediate cracked product; anda distillation column for separating the intermediate cracked product into one or more distillate fractions including a recycle stripping medium and a cracked product.

11. The system of claim 10, wherein the catalytic cracking system comprises a fluid catalytic cracking unit, a single regeneration dual catalyst cracking unit, and any combination thereof.

12. The system of claim 10, wherein the stripper further comprises a steam inlet disposed at the bottom of the stripper for receiving a steam stripping medium.

13. The system of claim 10, further comprising:a partial condenser for partially condensing the stripper overhead effluent into a liquid stripper overhead effluent and a vapor stripper overhead effluent; a recycle line for feeding liquid stripper overhead effluent back to the stripper as reflux; and a feed line for feeding vapor stripper overhead effluent to the catalytic cracking system.PATENT APPLICATION ATTORNEY DOCKET NO. 17421-256WO1 CLIENT REFERENCE NO 2024LCC008-WO 14. The system of claim 10, further comprising a heat exchanger for heating the stripping medium to a temperature between 160 and 420 °C upstream of the stripper.

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