METHODS FOR PROCESSING CONDENSATE FEEDSTOCKS

CROSS REFERENCE TO RELATED APPLICATION

This application claims the benefit of priority under 35 U.S.C. § 119 to India Provisional Application No. 202331084039 filed on Dec. 9, 2023, entitled “Methods For Processing Condensate Feedstocks,” the entire contents of which are incorporated by reference into the present application.

TECHNICAL FIELD

Embodiments of the present disclosure generally relate to chemical processing and, more specifically, to processes and systems utilized to convert condensate feedstocks to other chemicals.

BACKGROUND

Chemicals such as light olefins and fuels are typically manufactured by thermal cracking of ethane, propane, butane and naphtha. For example, ethylene produced by thermal cracking makes up about 50% of the total ethylene production. However, as demand rises for these basic intermediate compounds, other production sources are considered beyond traditional thermal cracking and/or steam cracking processes utilizing the available feedstocks listed above.

SUMMARY

Globally, the production of condensates has steadily increased in the last few decades. However, the high amounts of naphthenic and aromatic content in the condensates feedstock typically amplify coke formation and fouling, particularly in steam crackers. This is one of the constraints to process condensate directly in a steam cracker. However, the present embodiments utilize condensates, such as those with an API gravity range from 45-55 degrees, to produce chemicals and fuels by fluid catalytic cracking (“FCC”). The present embodiments allow for the use of condensate feedstock to yield a relatively high amount of chemicals and fuels. In particular, it has been discovered that condensate conversion may be enhanced by separating the condensate feedstock into at least two process streams, and subjecting the lighter stream to more severe FCC conditions than the heavier stream.

According to one or more embodiments, a condensate feedstock may be processed by a method that comprises passing the condensate feedstock to a first separation unit, and separating the condensate feedstock into at least a light fraction stream and a heavy fraction stream. The light fraction stream may have a maximum boiling point that is about equal to a minimum boiling point of the heavy fraction stream. The light fraction stream may have a maximum boiling point of from 230° C. to 380° C. and the heavy fraction stream may have a minimum boiling point of from 230° C. to 380° C. At least 90 wt. % of the condensate feedstock may be contained in the combination of the light fraction stream and the heavy fraction stream. The method may further comprise cracking the light fraction stream in a light fraction FCC reactor to form a first FCC effluent, and cracking the heavy fraction stream in a heavy fraction FCC reactor to from a second FCC effluent. The light fraction FCC reactor may operate with more severe cracking conditions than the heavy fraction FCC reactor. The method may further comprise passing the first FCC effluent and the second FCC effluent to a second separation unit and forming a plurality of downstream separated streams.

According to one or more additional embodiments, a condensate feedstock may be processed by a method that comprises passing the condensate feedstock to a first separation unit, and separating the condensate feedstock into at least a light fraction stream, an intermediate fraction stream, and a heavy fraction stream. The light fraction stream may have a maximum boiling point that is about equal to a minimum boiling point of the intermediate fraction stream, and the intermediate fraction stream may have a maximum boiling point that is about equal to a minimum boiling point of the heavy fraction stream. The light fraction stream may have a maximum boiling point of from 150° C. to 200° C. and the intermediate fraction stream may have a minimum boiling point of from 150° C. 200° C. The intermediate fraction stream may have a maximum boiling point of from 230° C. to 380° C. and the heavy fraction stream has a minimum boiling point of from 230° C. to 380° C. At least 90 wt. % of the condensate feedstock may be contained in the combination of the light fraction stream, the intermediate fraction stream, and the heavy fraction stream. The method may further comprise cracking the light fraction stream in a light fraction FCC reactor to form a first FCC effluent, and cracking the heavy fraction stream in a heavy fraction FCC reactor to from a second FCC effluent. The light fraction FCC reactor may operate with more severe cracking conditions than the light fraction FCC reactor. The method may further comprise passing the first FCC effluent and the second FCC effluent to a second separation unit and forming a plurality of downstream separated streams.

These and other embodiments are described in more detail in the Detailed Description. It is to be understood that both the foregoing general description and the following detailed description present embodiments of the subject technology, and are intended to provide an overview or framework for understanding the nature and character of the described technology as it is claimed. The accompanying drawings are included to provide a further understanding of the presently disclosed technology and are incorporated into and constitute a part of this specification. The drawings illustrate various embodiments and, together with the description, serve to explain the principles and operations of the presently described technology. Additionally, the drawings and descriptions are meant to be merely illustrative, and are not intended to limit the scope of the claims in any manner.

BRIEF DESCRIPTION OF THE DRAWINGS

The following detailed description of specific embodiments of the present disclosure can be best understood when read in conjunction with the following drawings, where like structure is indicated with like reference numerals and in which:

FIG. 1 schematically depicts a diagram of a condensate processing system, according to one or more embodiments described in this disclosure;

FIG. 2 schematically depicts a diagram of another condensate processing system, according to one or more embodiments described in this disclosure; and

FIG. 3 schematically depicts a diagram of yet another condensate processing system, according to one or more embodiments described in this disclosure.

Reference will now be made in greater detail to various embodiments, some embodiments of which are illustrated in the accompanying drawings. Whenever possible, the same reference numerals will be used throughout the drawings to refer to the same or similar parts.

For the purpose of describing the simplified schematic illustrations and descriptions of the relevant figures, the numerous valves, temperature sensors, electronic controllers and the like that may be employed and well known to those of ordinary skill in the art of certain chemical processing operations are not included. Further, accompanying components that are often included in typical chemical processing operations, such as air supplies, catalyst hoppers, and flue gas handling systems, are not depicted. Accompanying components that are in hydrocracking units, such as bleed streams, spent catalyst discharge subsystems, and catalyst replacement sub-systems are also not shown. It should be understood that these components are within the spirit and scope of the present embodiments disclosed. However, operational components, such as those described in the present disclosure, may be added to the embodiments described in this disclosure.

It should further be noted that arrows in the drawings refer to process streams. However, the arrows may equivalently refer to transfer lines which may serve to transfer process streams between two or more system components. Additionally, arrows that connect to system components define inlets or outlets in each given system component. The arrow direction corresponds generally with the major direction of movement of the materials of the stream contained within the physical transfer line signified by the arrow. Furthermore, arrows which do not connect two or more system components signify a product stream which exits the depicted system or a system inlet stream which enters the depicted system. Product streams may be further processed in accompanying chemical processing systems or may be commercialized as end products. System inlet streams may be streams transferred from accompanying chemical processing systems or may be non-processed feedstock streams. Some arrows may represent recycle streams, which are effluent streams of system components that are recycled back into the system. However, it should be understood that any represented recycle stream, in some embodiments, may be replaced by a system inlet stream of the same material, and that a portion of a recycle stream may exit the system as a system product.

Additionally, arrows in the drawings may schematically depict process steps of transporting a stream from one system component to another system component. For example, an arrow from one system component pointing to another system component may represent “passing” a system component effluent to another system component, which may include the contents of a process stream “exiting” or being “removed” from one system component and “introducing” the contents of that product stream to another system component. It should be understood that arrows in the relevant figures are not indicative of necessary or essential steps.

It should be understood that according to the embodiments presented in the relevant figures, an arrow between two system components may signify that the stream is not processed between the two system components. In other embodiments, the stream signified by the arrow may have substantially the same composition throughout its transport between the two system components. Additionally, it should be understood that in one or more embodiments, an arrow may represent that at least 75 wt. %, at least 90 wt. %, at least 95 wt. %, at least 99 wt. %, at least 99.9 wt. %, or even 100 wt. % of the stream is transported between the system components. As such, in some embodiments, less than all of the streams signified by an arrow may be transported between the system components, such as if a slip stream is present.

It should be understood that two or more process streams are “mixed” or “combined” when two or more lines intersect in the schematic flow diagrams of the relevant figures. Mixing or combining may also include mixing by directly introducing both streams into a like reactor, separation device, or other system component. For example, it should be understood that when two streams are depicted as being combined directly prior to entering a separation unit or reactor, that in some embodiments the streams could equivalently be introduced into the separation unit or reactor and be mixed in the reactor.

DETAILED DESCRIPTION

Embodiments of the present disclosure relate to methods for processing condensate feedstocks. In general, and as is discussed herein, the condensate conversion systems receive condensate feedstock and output chemicals and/or transportation fuels. The embodiments of FIGS. 1-3 are similar or identical in many ways, respectively, but include differences as described herein. Description of the embodiments of FIGS. 1, 2, and 3 may generally apply to the embodiments of the other figures, as would be understood by those skilled in the art. For example, concepts disclosed herein applicable to FIG. 1 may be equally applicable to FIG. 3, and vice versa, even if not explicitly stated as such herein.

Generally, in the embodiments described herein, a lighter portion of the condensate feedstock is subjected to more severe FCC conditions than a heaver portion of the condensate feedstock. In such an arrangement, it has been discovered that lesser desired yields, such as fuel gas, may be produced as compared to more desired yields, such as catalyst cracked naphtha and light olefins.

As used in this disclosure, a “reactor,” such as an FCC reactor, described herein, refers to a vessel in which one or more chemical reactions may occur between one or more reactants optionally in the presence of one or more catalysts. For example, a reactor may include a tank or tubular reactor, a gas phase reactor, a continuous stirred-tank reactor (CSTR), or a plug flow reactor. Example reactors include fluidized bed reactors. Reactors, as described herein, may include a series of separate reactors. Additionally, reactors may include separation devices, such as those which separate catalyst from the reaction product. Such reactors may also include catalyst regeneration sections, as would be understood by those skilled in the art.

As used in this disclosure, a “catalyst” refers to any substance which increases the rate of a specific chemical reaction. Catalysts described in this disclosure may be utilized to promote various reactions, such as, but not limited to, cracking reactions. As used in this disclosure, a “cracking catalyst” increases the rate of a cracking reaction. Such catalysts may have dual functionality in some embodiments. The methods described herein should not necessarily be limited by specific catalytic materials. As described herein, the catalysts, including those used for cracking, may be fluidized in configuration and utilize gaseous reactants. However, other configurations are contemplated.

As used in this disclosure, a “separation unit” refers to any separation device or system of separation devices that at least partially separates one or more chemicals that are mixed in a process stream from one another. For example, a separation unit may selectively separate differing chemical species, phases, or sized material from one another, forming one or more chemical fractions. Examples of separation units include, without limitation, distillation columns, flash drums, knock-out drums, knock-out pots, centrifuges, cyclones, filtration devices, traps, scrubbers, expansion devices, membranes, solvent extraction devices, and the like. It should be understood that separation processes described in this disclosure may not completely separate all of one chemical constituent from all of another chemical constituent. It should be understood that the separation processes described in this disclosure “at least partially” separate different chemical components from one another, and that even if not explicitly stated, it should be understood that separation may include only partial separation.

In one or more embodiments, a condensate feedstock is the primary or sole feed utilized to form chemical products. As described herein, a “condensate feedstock” generally refers to a hydrocarbon liquid that condensed and formed when primarily gas is extracted from underground gas reservoirs, as is understood by those skilled in the art. Such condensate feedstocks may have chemical species as light as C₃hydrocarbons and may have a final boiling point of at least 550° C., such as from 550° C. to 650° C. In some embodiments, the condensate feedstock may have a less than or equal to 2 wt. % boiling above 565° C. Such condensate feedstocks may be those produced from the Jafurah gas field in Saudi Arabia, termed herein as “Jafurah condensate”. Typical examples of Jafurah condensate feedstock compositions are provided in Table 1.

TABLE 1

Sample-1
Sample-2
Sample-3

(wt. %)
(wt. %)
(wt. %)

Properties:

API Gravity
48
46
49

Total Sulfur (% wt)
0.215
0.198
0.125

Salt in Crude (PTB)
12
7.27
0.89

Density @ 60° F. (kg/cm3)
0.7909
0.7962
0.7847

Composition:

C1-C4
1.5
0.3
0.4

Naphtha to 185° C.
37
34
40.7

Kerosene 185° C.-245° C.
13.7
14.9
17.6

Gas oil 245° C.-365° C.
25.4
27.1
25

Vacuum gas oil 365° C.-565° C.
19.8
21.2
14.3

Residue 565° C.
2.6
2.5
2

According to some embodiments, the condensate feedstocks described herein may have an API gravity of from 45 degrees to 55 degrees. For example, the condensate feedstocks described herein may have an API gravity of from 45 degrees to 46 degrees, from 46 degrees to 47 degrees, from 47 degrees to 48 degrees, from 48 degrees to 49 degrees, from 49 degrees to 50 degrees, from 50 degrees to 51 degrees, from 51 degrees to 52 degrees, from 52 degrees to 53 degrees, from 53 degrees to 54 degrees, from 54 degrees to 55 degrees, or any combination of one or more of these ranges.

Now referring to FIG. 1, condensate processing system 101 is depicted. The condensate processing system 101 may include at least a first separation unit 120, a heavy fraction FCC reactor 140, a light fraction FCC reactor 130, and a second separation unit 150. These system components will be described in detail herein.

According to one or more embodiments, the condensate feedstock may be passed to the first separation unit 120. Condensate feed stream 108 may consist of the condensate feedstock. In some embodiments, the condensate feedstock may be processed in a de-salter 110, which may remove at least a portion of salt from the condensate feedstock prior to passing the condensate feedstock to the first separation unit 120. It should be understood that some embodiments may not include a de-salter 110, and condensate feed stream 108 may be passed directly to the first separation unit 120. In embodiments that include a de-salter 110, condensate feedstock may be passed to the first separation unit 120 via condensate feed stream 112 after being de-salted in the de-salter 110. According to additional embodiments, and not shown in FIG. 1, the condensate feedstock may be further treated to remove other impurities, such as, and without limitation, alkali metals, nitrogen, sulfur. Such treatments may be by hydrotreatment of the condensate feedstock or use of single or multiple guard beds to remove the impurities in the feedstock.

Still referring to FIG. 1, according to embodiments, the condensate feedstock may be separated into at least two streams by the first separation unit 120. The first separation unit 120 may be any suitable separation unit, such as, and without limitation, a flash vessel or fractionator/distillation column that separates feedstock based on the boiling point at a specified cut point. As described herein, the “cut point” in a separation generally identifies the approximate final boiling point of a lighter fraction and approximate initial boiling point of a heavier fraction based on atmospheric pressure conditions. In some embodiments, such as depicted in FIG. 1, the condensate feed stream 112 is separated into only two streams, the light fraction stream 122 and the heavy fraction stream 124. If other streams are produced by the first separation unit 120 (besides the light fraction stream 122 and the heavy fraction stream 124), those streams may be only a relatively small portion of the condensate feed stream 112. For example, at least 90 wt. %, at least 95 wt. %, at least 99 wt. %, at least 99.9 wt. %, or 100 wt. % of the condensate feed stream 112 may be contained in the combination of the light fraction stream 122 and the heavy fraction stream 124.

According to embodiments, the cut point between the light fraction stream 122 and the heavy fraction stream 124 may be in a range of from 230° C. to 380° C. In such embodiments, the light fraction stream 122 may have a maximum boiling point of from 230° C. to 380° C. and the heavy fraction stream 124 may have a minimum boiling point of from 230° C. to 380° C. According to some embodiments, the cut point between the light fraction stream 122 and the heavy fraction stream 124 may be in a range of from 230° C. to 260° C. In such embodiments, the light fraction stream 122 may have a maximum boiling point of from 230° C. to 260° C. and the heavy fraction stream 124 may have a minimum boiling point of from 230° C. to 260° C. According to some other embodiments, the cut point between the light fraction stream 122 and the heavy fraction stream 124 may be in a range of from 350° C. to 380° C. In such embodiments, the light fraction stream 122 may have a maximum boiling point of from 350° C. to 380° C. and the heavy fraction stream 124 may have a minimum boiling point of from 350° C. to 380° C.

As depicted in FIG. 1, the light fraction stream 122 and the heavy fraction stream 124 may be passed, respectively to the light fraction FCC reactor 130 and the heavy fraction FCC reactor 140. Cracking of the light fraction stream 122 in the light fraction FCC reactor 130 may form a first FCC effluent 132, and cracking of the heavy fraction stream 124 in the heavy fraction FCC reactor 140 may form a second FCC effluent 142. As used in this disclosure, “cracking” may generally refers to a chemical reaction where a molecule having carbon to carbon bonds is broken into more than one molecule by the breaking of one or more of the carbon to carbon bonds, or is converted from a compound which includes a cyclic moiety, such as a cycloalkane, cycloalkane, naphthalene, an aromatic or the like, to a compound which does not include a cyclic moiety or contains fewer cyclic moieties than prior to cracking. Cracking may also include reduction in alkene bonds (i.e., transformation of alkene bonds to alkane bonds). As is well understood by those skilled in the art, FCC is an abbreviation for fluid catalytic cracking, which generally refers to utilizes fluidized catalytic particles which contact a feed that is a gas phase. It is contemplated that a wide variety of catalyst may be utilized in the light fraction FCC reactor 130 and the heavy fraction FCC reactor 140, respectively. For example, zeolitic catalysts may be suitable.

As is described herein, in general the light fraction FCC reactor 130 may operate with more severe cracking conditions than the heavy fraction FCC reactor 140 (sometimes also referred to herein as the heavy fraction FCC reactor 140 operating with more mild operating conditions than the light fraction FCC reactor 130). Generally, more severe cracking conditions are defined herein as those conditions that better promote cracking with in a reactor unit. As described herein, one reaction condition is more severe than another if more cracking is observed when each reactor processes the same feedstock hydrocarbon. Variables that may affect severity of cracking conditions include reactor temperature, residence time, catalyst composition, catalyst to feed ratio. For example, higher temperatures, greater catalyst to feed ratio, and longer residence times generally correspond to more severe cracking conditions. In some embodiments, the use of a riser may correspond with additional residence time as compared to a downer, as is described in detail herein. Additionally, more catalytically active catalysts better promote cracking and lead to more severe cracking reaction conditions.

As described, the light fraction FCC reactor 130 operates with more severe cracking conditions than the heavy fraction FCC reactor 140. In some embodiments, the light fraction FCC reactor 130 operates at a higher temperature than the heavy fraction FCC reactor 140. For example, the light fraction FCC reactor 130 may operate at temperatures at least 5° C. greater, at least 10° C. greater, at least 20° C. greater, at least 30° C. greater, at least 40° C. greater, or even at least 50° C. greater than the heavy fraction FCC reactor 140. In some embodiments, the light fraction FCC reactor 130 may operate at a temperature of from 600 to 700, and the heavy fraction FCC reactor 140 may operate at a temperature of from 550° C. to 650° C. For example, the light fraction FCC reactor 130 may operate at a temperature of from 600° C. to 625° C., from 625° C. to 650° C., or from 650° C. to 675° C. or from 675° C. to 700° C. . . . Additionally, the heavy fraction FCC reactor 140 may operate at a temperature of from 550° C. to 575° C., from 575° C. to 600° C., from 600° C. to 625° C., or from 625° C. to 650° C.

According to some embodiments, the catalyst to feed ratio of the light fraction FCC reactor 130 may be greater than that of the heavy fraction FCC reactor 140. The catalyst to feed ratio describes the relative amount of catalyst per amount of hydrocarbon feed, such as the light fraction stream 122 or the heavy fraction stream 124 in the light fraction FCC reactor 130 and heavy fraction FCC reactor 140, respectively. Greater catalyst to feed ratio may cause more severe cracking conditions. In some embodiments, the catalyst to feed ratio of the light fraction FCC reactor 130 may be at least 1 greater, at least 2 greater, at least 4 greater, at least 6 greater, at least 8 greater, or even at least 10 greater than the catalyst to feed ratio of the heavy fraction FCC reactor 140. Catalyst to feed ratio is described in weight/weight terms unless otherwise specified herein. In some embodiments, the catalyst to feed ratio by weight in the light fraction FCC reactor 130 may be from 5 to 40. In some embodiments, the catalyst to feed ratio by weight in the heavy fraction FCC reactor 140 may be from 5 to 20.

According to some embodiments, the residence time of the light fraction FCC reactor 130 may be greater than the residence time (e.g., 1-10 times) of the heavy fraction FCC reactor 140. Generally speaking, residence time refers to the average time that the catalyst interacts with the light fraction stream 122 or heavy fraction stream 124 in the light fraction FCC reactor 130 or heavy fraction FCC reactor 140, respectively. According to embodiments, the residence time of the light fraction FCC reactor 130 may be at least 0.1 s greater, at least 0.2 s greater, at least 0.3 s greater, at least 0.4 s greater, or even at least 0.5 s greater than the residence time of the heavy fraction FCC reactor 140.

In some embodiments, in general, greater residence times may be present when a riser reactor is utilized as the light fraction FCC reactor 130 and/or the heavy fraction FCC reactor 140 as compared to when a downer reactor is utilized as the light fraction FCC reactor 130 and/or the heavy fraction FCC reactor 140. Selection of a riser or downer for the light fraction FCC reactor 130 and heavy fraction FCC reactor 140 may be one way to influence residence time different between the light fraction FCC reactor 130 and the heavy fraction FCC reactor 140. For example, in general, the greater residence times in the light fraction FCC reactor 130 as compared to the heavy fraction FCC reactor 140 may be realized by selecting a riser for the light fraction FCC reactor 130 and a downer for the heavy fraction FCC reactor 140. Alternatively, at the least both the light fraction FCC reactor 130 and the heavy fraction FCC reactor 140 may be risers or downers, respectively. However, in yet additional embodiments, the selection of a downer as the light fraction FCC reactor 130 and a riser as the heavy fraction FCC reactor 140 may be utilized, where reactor parameters are chosen such that the light fraction FCC reactor 130 operates with more severe reaction conditions than the heavy fraction FCC reactor 140.

In additional embodiments, the catalyst composition utilized in the light fraction FCC reactor 130 may be more catalytically active than that in the heavy fraction FCC reactor 140. For example, the catalyst utilized may be a zeolitic catalyst, such as catalyst that includes ZSM-5 zeolite. In some embodiments, ZSM-5 may be mesoporous, meaning the ZSM-5 has an average pore size of from 2 nm to 100 nm (rather than conventional ZSM-5 zeolites that have only a microstructure and average pore size of less than 2 nm. In some embodiments, more severe cracking conditions may be present in the light fraction FCC reactor 130 than the heavy fraction FCC reactor 140 by utilizing a greater amount of mesoporous ZSM-5 zeolite in the light fraction FCC reactor 130 than in the heavy fraction FCC reactor 140.

Following cracking of the light fraction stream 122 and the heavy fraction stream 124, resulting in the formation of the first FCC effluent 132 and second FCC effluent 142, the first FCC effluent 132 and the second FCC effluent 142 may be passed to the second separation unit 150. The first FCC effluent 132 and second FCC effluent 142 may be separately passed to the second separation unit 150 as depicted in FIG. 1, or may be combined and sent together to the second separation unit 150. The second separation unit 150 may be a distillation column/fractionator, according to some embodiments, as is depicted in FIG. 1. However, a series of separation devices may be utilized, as would be recognized by those skilled in the art. Various downstream separated streams may be formed by the separation of the first FCC effluent 132 and the second FCC effluent 142. For example, in some embodiments, effluents of the second separation unit 150 (the downstream separated streams) may include fuel gas 172, stream 178 that includes liquefied petroleum gas (LPG) along with C₃-C₄light olefins, cat-cracked naphtha 154, light cycle oil 156, and heavy cycle oil 158. While these downstream separated streams may sometimes vary in composition, in general, the fuel gas 172 includes H₂and C₁-C₂species, stream 178 includes the liquefied petroleum gas which includes C₃-C₄paraffins along with C₃-C₄light olefins, the cat-cracked naphtha 154 includes C₅hydrocarbons up to about 220° C. boiling point hydrocarbons (e.g., boiling in a range of from 210° C. to 230° C.), and the light cycle oil 156 include hydrocarbons boiling from about 220° C. (e.g., in a range from 210° C. to 230° C.) to about 350° C. (e.g., in range from 340° C. to 360° C.). The heavy cycle oil 158 may include hydrocarbons boiling over about 350° C. (e.g., in a range from 340° C. to 360° C.).

Still referring to FIG. 1, in some embodiments, the fuel gas 172 and stream 178 may exit the second separation unit 150 as stream 152 and be separated into respective streams. The fuel gas 172 may be utilized as a product stream, or may be utilized in the condensate processing system 101 as a fuel for, e.g., heating the light fraction stream 122 and/or heavy fraction stream 124. The cat-cracked naphtha 154 may be passed to the saturation unit 170. The saturation unit 170 may operate to saturate diolefins in the cat-cracked naphtha 154 and improve the olefins content in order to improve yields in the mixed feed steam cracker unit 160. The saturation unit 170 may be a typical naphtha/gasoline hydrotreater that operates at 200-320° C. at a pressure of 25-45 barg with a CoMo hydrotreating catalyst. The saturation unit effluent 168 may exit the saturation unit 170.

In one or more embodiments, both the stream 178 (that is after separation of C₃-C₄light olefins) and the saturation unit effluent 168 may be passed to the mixed feed steam cracker unit 160 to form a stream cracked effluent 162. That is, in some embodiments, the stream 178 may be separated into a stream containing C₃-C₄light olefins, which may be passed to an olefin separation unit (not shown in FIG. 1) and a stream containing C₃-C₄parrafins, which is passed to the mixed feed steam cracker unit 160. The mixed feed steam cracker unit 160 may be a combination of different thermal (pyrolysis) steam cracking furnaces that can process feeds such as ethane, propane, butanes, as well as liquids such as naphtha (low or no olefin content) and gas oils (boiling between 180° C. up to 365° C.). Typically, each furnace may be customized (coil material of construction, layout and residence times) to crack a narrow boiling point range of material. Multiple cracking furnaces in the mixed feed steam cracker unit 160 may operate in parallel processing different cuts. The products from each furnace can be combined and processed in a downstream olefins separation section that can be integrated with the catalytic cracking downstream section. The thermal cracking furnaces may operate at outlet temperatures between 700° C. to 900° C. and an inlet pressure of 1.5 barg or greater.

Still referring to FIG. 1, the light cycle oil 156 may be passed to the diesel preparation unit 180, which may form diesel 182. The diesel preparation unit 180 may be a typical diesel hydrotreating unit or a mild hydrocracker. In some embodiments, the diesel preparation unit 180 may be an LCO (Light Cycle Oil) hydrotreating/mild hydrocracking unit operating with a target to produce material that can be either sold as diesel or blended with other diesel components. A typical unit may operate at 350-420° C. and a pressure of 50-100 barg. A variety of available mild hyrocracking catalyst (CoMo or NiMo catalysts) may be used.

The heavy cycle oil 158 may exit the condensate processing system 101 as a product as fuel oil 174, which may be utilized as a fuel for catalytic cracker heat balance requirements or sold to others. In some embodiments, a portion (or all) of the heavy cycle oil 158 may be recycled in the condensate processing system 101. In particular, as shown in FIG. 1, the heavy cycle oil 176 may be combined with the heavy fraction stream 124, or may be passed directly to the heavy fraction FCC reactor 140.

Now referring to FIG. 2, another condensate processing system 102 is depicted. The condensate processing system 102 may be similar or identical to the condensate processing system 101 of FIG. 1 except where described otherwise. In particular, the condensate processing system 102 may utilize different processing of stream 178 and the cat-cracked naphtha 154. According to some embodiments, stream 178 (including the liquefied petroleum gas along with C₃-C₄light olefins) may be passed to an olefin separation unit 190, where stream 178 is separated into olefins 194 and non-olefins 196. Additionally, the cat-cracked naphtha 154 may be passed to a gasoline preparation unit 192, which produces gasoline 198. The Gasoline preparation unit 192 may be a gasoline hydrotreater, similar to a naphtha preparation unit. The target of this unit may be to produce a material that will either meet gasoline specifications or can be blended with other suitable material in order to meet gasoline specifications.

Now referring to FIG. 3, another condensate processing system 103 is depicted. The condensate processing system 103 may be similar or identical to the condensate processing system 101 of FIG. 1 except where described otherwise. In particular, the condensate processing system 103 may utilize a different separation scheme in the first separation unit 120. According to one or more embodiments, the first separation unit 120 may separate the condensate feed stream 112 into at least a light fraction stream 122, an intermediate fraction stream 126, and a heavy fraction stream 124. Generally, the light fraction stream 122 may have lighter components than the intermediate fraction stream 126, and the intermediate fraction stream 126 may have lighter components than the heavy fraction stream 124. In some embodiments, such as depicted in FIG. 3, the condensate feed stream 112 is separated into only three streams, the light fraction stream 122, the intermediate fraction stream 126, and the heavy fraction stream 124. If other streams are produced by the first separation unit 120 (besides the light fraction stream 122, the intermediate fraction stream 126, and the heavy fraction stream 124), those streams may be only a relatively small portion of the condensate feed stream 112. For example, at least 90 wt. %, at least 95 wt. %, at least 99 wt. %, at least 99.9 wt. %, or 100 wt. % of the condensate feed stream 112 may be contained in the combination of the light fraction stream 122, the intermediate fraction stream 126, and the heavy fraction stream 124.

According to embodiments, the cut point between the light fraction stream 122 and the intermediate fraction stream 126 may be in a range of from 150° C. to 200° C. In such embodiments, the light fraction stream 122 may have a maximum boiling point of from 150° C. to 200° C. and the intermediate fraction stream 126 may have a minimum boiling point of from 150° C. to 200° C. The cut point between the intermediate fraction stream 126 and the heavy fraction stream 124 may be in a range of from 230° C. to 380° C. In such embodiments, the intermediate fraction stream 126 may have a maximum boiling point of from 230° C. to 380° C. and the heavy fraction stream 124 may have a minimum boiling point of from 230° C. to 380° C. According to some embodiments, the cut point between the intermediate fraction stream 126 and the heavy fraction stream 124 may be in a range of from 230° C. to 260° C. In such embodiments, the intermediate fraction stream 126 may have a maximum boiling point of from 230° C. to 260° C. and the heavy fraction stream 124 may have a minimum boiling point of from 230° C. to 260° C. According to some other embodiments, the cut point between the intermediate fraction stream 126 and the heavy fraction stream 124 may be in a range of from 350° C. to 380° C. In such embodiments, the intermediate fraction stream 126 may have a maximum boiling point of from 350° C. to 380° C. and the heavy fraction stream 124 may have a minimum boiling point of from 350° C. to 380° C.

Still referring to FIG. 3, the intermediate fraction stream 126 may be passed to a kerosene/diesel preparation unit 128. The kerosene/diesel preparation unit 128 may prepare diesel or kerosene 134 based on the exact specifications of the intermediate fraction stream 126. The kerosene/diesel preparation unit 128 may operate similarly to the diesel preparation unit 180 described with respect to FIG. 1. In additional embodiments, the intermediate fraction stream 126 may be combined with the cat-cracked naphtha 154 and the combined stream can be processed in saturation unit 170.

While not depicted in a separate figure, it is contemplated that the post separation scheme of FIG. 2 (that is past the second separation unit 150) may be utilized in conjunction with the three-stream separation scheme of FIG. 3.

Several specific embodiments are now described. It should be understood that these embodiments may be combinable with one another, where some aspects of a particular embodiment are combinable with aspects of a different embodiment.

In a first embodiment, the condensate processing system 101 of FIG. 1 may utilize a riser for the light fraction FCC reactor 130 and a riser for the heavy fraction FCC reactor 140. The first separation unit 120 may produce only two streams, the light fraction stream 122 and the heavy fraction stream 124, with a cut point of about 245° C. (e.g., from 230° C. to 260° C.). Approximately 40-80 wt. % of the condensate feed stream 112 may be processed in light fraction FCC reactor 130. The conditions in the light fraction FCC reactor 130 include reaction temperature of 600-675° C., catalyst/feed ratio of 5-40 wt/wt, residence time of 2-3 sec. The catalyst mix may consist of (i) modified USY from 10-75 wt. % (with or without rare earth additives); and (ii) mesoporous H-ZSM-5 based additive from 90-25 wt. %, respectively. The heavy fraction stream 124 may be approximately 20-60 wt. % of the condensate feed stream 112 and may be processed in heavy fraction FCC reactor 140. The conditions in the heavy fraction FCC reactor 140 may include reaction temperature from 550-650° C., catalyst/feed ratio 5-20 wt/wt, and residence time of 2-3 sec. The catalyst mixture may consist of (i) USY from 20-80 wt. % (with or without rare earth modified additives); and (ii) mesoporous H-ZSM-5 based additive from between 20-80 wt. %, respectively.

A second embodiment is identical to the first embodiment, but utilizes a cut point between the light fraction stream 122 and the heavy fraction stream 124 of about 365° C. (e.g., 350° C. to 380° C.).

A third embodiment is identical to the first embodiment, but utilizes the post-separation scheme of the condensate processing system 102 of FIG. 2.

A fourth embodiment is identical to the second embodiment, but utilizes the post-separation scheme of the condensate processing system 102 of FIG. 2.

A fifth embodiment is identical to the first embodiment, but utilizes a downer as the heavy fraction FCC reactor 140. The conditions in the heavy fraction FCC reactor 140 include reaction temperature between 550-650° C., catalyst/feed ratio of 5-20 wt/wt, residence time of 0.1-1 sec. The catalyst mix may consist of (i) modified USY from 20-80 wt. % (with or without rare earth additives); and (ii) mesoporous H-ZSM-5 based additive from 20-80 wt. %, respectively.

A sixth embodiment is identical to the fifth embodiment, but utilizes a cut point between the light fraction stream 122 and the heavy fraction stream 124 of about 365° C. (e.g., 350° C. to 380° C.).

A seventh embodiment is identical to the first embodiment, but utilizes a downer for the light fraction FCC reactor 130 and a downer for the heavy fraction FCC reactor 140. The conditions in the light fraction FCC reactor 130 include reaction temperature of 600-675° C., catalyst/feed ratio of 5-40 wt/wt, residence time of 0.1-1 sec. The catalyst mix may consist of (i) modified USY from 10-75 wt. % (with or without rare earth additives); and (ii) mesoporous H-ZSM-5 based additive from 90-25 wt. %, respectively. The heavy fraction stream 124 may be approximately 20-60 wt. % of the condensate feed stream 112 and may be processed in heavy fraction FCC reactor 140. The conditions in the heavy fraction FCC reactor 140 may include reaction temperature from 550-650° C., catalyst/feed ratio 5-20 wt/wt, and residence time of 0.1-1 sec. The catalyst mixture may consist of (i) USY from 20-80 wt. % (with or without rare earth modified additives); and (ii) mesoporous H-ZSM-5 based additive from between 20-80 wt. %, respectively.

An eighth embodiment is identical to the seventh embodiment, but utilizes a cut point between the light fraction stream 122 and the heavy fraction stream 124 of about 365° C. (e.g., 350° C. to 380° C.).

A ninth embodiment, the condensate processing system 103 is utilized where the cut point between the light fraction stream 122 and the intermediate fraction stream 126 is about 185° C. (e.g., from 150° C. to 200° C.), and where the cut point between the intermediate fraction stream 126 and the heavy fraction stream 124 is about 245° C. (e.g., from 230° C. to 260° C.).

A tenth embodiment is identical to the ninth embodiment, but utilizes a cut point between the intermediate fraction stream 126 and the heavy fraction stream 124 of about 365° C. (e.g., from 350° C. to 380° C.).

Numerous aspects are included in the present disclosure. One aspect is a method for processing a condensate feedstock, the method comprising: passing the condensate feedstock to a first separation unit, and separating the condensate feedstock into at least a light fraction stream and a heavy fraction stream, wherein: the light fraction stream has a maximum boiling point that is about equal to a minimum boiling point of the heavy fraction stream; the light fraction stream has a maximum boiling point of from 230° C. to 380° C. and the heavy fraction stream has a minimum boiling point of from 230° C. to 380° C.; and at least 90 wt. % of the condensate feedstock is contained in the combination of the light fraction stream and the heavy fraction stream; cracking the light fraction stream in a light fraction FCC reactor to form a first FCC effluent; cracking the heavy fraction stream in a heavy fraction FCC reactor to from a second FCC effluent, wherein the light fraction FCC reactor operates with more severe cracking conditions than the heavy fraction FCC reactor; passing the first FCC effluent and the second FCC effluent to a second separation unit and forming a plurality of downstream separated streams.

Another aspect is any previous aspect or combination of previous aspects, wherein one or more of: the condensate feedstock has an API gravity of from 45 degrees to 55 degrees; the condensate feedstock has a final boiling point of from 550 to 650° C.; or the condensate feedstock has less than or equal to 5 wt. % boiling above 565° C.

Another aspect is any previous aspect or combination of previous aspects, wherein: the light fraction stream has a maximum boiling point of from 230° C. to 260° C. and the heavy fraction stream has a minimum boiling point of from 230° C. to 260° C.; or the light fraction stream has a maximum boiling point of from 350° C. to 380° C. and the heavy fraction stream has a minimum boiling point of from 350° C. to 380° C.

Another aspect is any previous aspect or combination of previous aspects, further comprising removing at least a portion of salt from the condensate feedstock prior to passing the condensate feedstock to the first separation device.

Another aspect is any previous aspect or combination of previous aspects, wherein the light fraction FCC reactor operates at a higher temperature than the heavy fraction FCC reactor.

Another aspect is any previous aspect or combination of previous aspects, wherein the light fraction FCC reactor operates with a greater catalyst to feed ratio than the heavy fraction FCC reactor.

Another aspect is any previous aspect or combination of previous aspects, wherein the light fraction FCC reactor operates with a greater residence time than the heavy fraction FCC reactor.

Another aspect is any previous aspect or combination of previous aspects, wherein: the light fraction FCC reactor is a riser and the heavy fraction FCC reactor is a riser; the light fraction FCC reactor is a downer and the heavy fraction FCC reactor is a downer; the light fraction FCC reactor is a riser and the heavy fraction FCC reactor is a downer; or the light fraction FCC reactor is a downer and the heavy fraction FCC reactor is a riser.

Another aspect is any previous aspect or combination of previous aspects, wherein all of the condensate feedstock is contained in the combination of the light fraction stream and the heavy fraction stream.

Another aspect is any previous aspect or combination of previous aspects, wherein a greater amount of mesoporous zeolite is utilized in the light fraction FCC reactor than in the heavy fraction FCC reactor.

Another aspect is any previous aspect or combination of previous aspects, wherein the plurality of downstream separated streams comprise at least: a fuel gas stream; a stream comprising C₃-C₄paraffins and C₃-C₄light olefins that is passed to mixed feed steam cracker unit; a cat-cracked naphtha stream that is passed to a saturation unit; a light cycle oil stream that is passed to a diesel preparation unit; and a heavy cycle oil stream.

Another aspect is any previous aspect or combination of previous aspects, wherein the plurality of downstream separated streams comprise at least: a fuel gas stream; a stream comprising C₃-C₄paraffins and C₃-C₄light olefins that is passed to an olefin separation unit; a cat-cracked naphtha stream that is passed to a gasoline preparation unit; a light cycle oil stream that is passed to a diesel preparation unit; and a heavy cycle oil stream.

Another aspect is a method for processing a condensate feedstock, the method comprising: passing the condensate feedstock to a first separation unit, and separating the condensate feedstock into at least a light fraction stream, an intermediate fraction stream, and a heavy fraction stream, wherein: the light fraction stream has a maximum boiling point that is about equal to a minimum boiling point of the intermediate fraction stream, and the intermediate fraction stream has a maximum boiling point that is about equal to a minimum boiling point of the heavy fraction stream; the light fraction stream has a maximum boiling point of from 150° C. to 200° C. and the intermediate fraction stream has a minimum boiling point of from 150° C. to 200° C.; the intermediate fraction stream has a maximum boiling point of from 230° C. to 380° C. and the heavy fraction stream has a minimum boiling point of from 230° C. to 380° C.; and at least 90 wt. % of the condensate feedstock is contained in the combination of the light fraction stream, the intermediate fraction stream, and the heavy fraction stream; cracking the light fraction stream in a light fraction FCC reactor to form a first FCC effluent; cracking the heavy fraction stream in a heavy fraction FCC reactor to from a second FCC effluent, wherein the light fraction FCC reactor operates with more severe cracking conditions than the light fraction FCC reactor; passing the first FCC effluent and the second FCC effluent to a second separation unit and forming a plurality of downstream separated streams.

Another aspect is any previous aspect or combination of previous aspects, wherein the condensate feedstock has an API gravity of from 45 degrees to 55 degrees.

Another aspect is any previous aspect or combination of previous aspects, wherein: the intermediate fraction stream has a maximum boiling point of from 230° C. to 260° C. and the heavy fraction stream has a minimum boiling point of from 230° C. to 260° C.; or the intermediate fraction stream has a maximum boiling point of from 350° C. to 380° C. and the heavy fraction stream has a minimum boiling point of from 350° C. to 380° C.

Another aspect is any previous aspect or combination of previous aspects, wherein the light fraction FCC reactor operates at a higher temperature than the heavy fraction FCC reactor.

Another aspect is any previous aspect or combination of previous aspects, wherein the light fraction FCC reactor operates with a greater catalyst to feed ratio than the heavy fraction FCC reactor.

Another aspect is any previous aspect or combination of previous aspects, wherein the light fraction FCC reactor operates with a greater residence time than the heavy fraction FCC reactor.

Another aspect is any previous aspect or combination of previous aspects, wherein the plurality of downstream separated streams comprise at least: a fuel gas stream; a stream comprising C₃-C₄paraffins and C₃-C₄light olefins, wherein at least the C₃-C₄parrafins that is passed to mixed feed steam cracker unit; a cat-cracked naphtha stream that is passed to a saturation unit; a light cycle oil stream that is passed to a diesel preparation unit; and a heavy cycle oil stream.

For the purposes of describing and defining the present disclosure it is noted that the terms “about” or “approximately” are utilized in this disclosure to represent the inherent degree of uncertainty that may be attributed to any quantitative comparison, value, measurement, or other representation. The terms “about” and/or “approximately” are also utilized in this disclosure to represent the degree by which a quantitative representation may vary from a stated reference without resulting in a change in the basic function of the subject matter at issue.

It is noted that one or more of the following claims utilize the term “wherein” as a transitional phrase. For the purposes of defining the present technology, it is noted that this term is introduced in the claims as an open-ended transitional phrase that is used to introduce a recitation of a series of characteristics of the structure and should be interpreted in like manner as the more commonly used open-ended preamble term “comprising.”

Any quantitative value expressed in the present application may be considered to include open-ended embodiments consistent with the transitional phrases “comprising” or “including” as well as closed or partially closed embodiments consistent with the transitional phrases “consisting of” and “consisting essentially of.”

It is also noted that recitations herein of “at least one” component, element, etc., should not be used to create an inference that the alternative use of the articles “a” or “an” should be limited to a single component, element, etc.

METHODS FOR PROCESSING CONDENSATE FEEDSTOCKS

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