Method and system for defining gas device

Abstract

Methods and systems are provided for defining a gas plant during fluidized catalytic cracking unit (FCCU) retrofit that is part of an olefin production system. These methods and systems include a cooler unit in a gas concentration unit downstream of the FCCU. Other measures also include installing a stripper unit downstream of the regenerator of the FCCU or installing a quench line in the reactor of the FCCU to reduce the contact time of the hydrocarbon feedstock with the catalyst. These processes and systems may also result in an increase in propylene yield of an olefin production system.

Description

[0001] Inventors: Madhavendra Kapkoti, Yi Yang, Rajeev Ranjan, Matthew James Griffith, and Rahul Radhakrishna Pillai

[0002] Cross Reference to Related Applications

[0003] This application claims priority to U.S. Non-Provisional Patent Application Serial No. 18 / 336,931, filed June 16, 2023, which is incorporated herein by reference. TECHNICAL FIELD

[0004] The present disclosure relates to methods and systems for defining a gas plant, such as during a fluid catalytic cracking unit (FCCU) revamp. More particularly, the present disclosure relates to methods and systems for reducing the load on a gas compressor unit at a gas plant. BACKGROUND

[0005] Fluid catalytic cracking (FCC) in a refinery is a key process for converting hydrocarbon feedstocks into valuable petrochemical products, such as ethylene and propylene. FCCUs utilize reactors known as risers to contact hydrocarbon feedstocks with catalysts to facilitate the conversion of the hydrocarbon feedstocks into petrochemical products. Advances in FCCU technology, such as dual riser technology (KBR MAXOFIN™ technology), employ multiple risers to facilitate the conversion of different hydrocarbon feedstocks into ethylene and / or propylene rich effluents in respective risers. The increasing demand for propylene necessitates modifications to existing gas plants, installation of new FCC equipment to maximize propylene yield. Gas plants upgraded to the latest FCCU technology readily enable higher propylene yields. However, the magnitude of propylene yield is often limited by the original design of the gas plant. SUMMARY

[0006] Applicants have recognized that existing gas plants can be maximized for propylene recovery by implementing one or more methods and systems for defining a gas plant described herein.

[0007] Certain embodiments include an olefin production system for defining a wet gas compressor in a gas concentration unit. In certain embodiments, the olefin production system includes a fluidized catalytic cracking unit, a fractionator, and a gas concentration unit containing an overhead condenser, a cooler, a receiver, and a wet gas compressor. The fluidized catalytic cracking unit has a riser reactor and a regenerator and is configured to receive a hydrocarbon feedstock and produce a cracked product stream containing light and heavy paraffins, naphtha, aromatics, and olefins. In certain embodiments, the riser reactor can include a quench line to introduce a quench fluid into the riser reactor at 1.5 seconds after the hydrocarbon feedstock contacts the catalyst. In certain embodiments, the riser reactor is a dual or multi-riser reactor. The fractionator is in fluid communication with the fluidized catalytic cracking unit and is configured to receive the cracked product stream and separate it into (i) a vapor product stream containing ethylene and propylene and light naphtha, (ii) a first crude naphtha product stream, and (iii) a liquid product stream containing one or more of heavy naphtha, light cycle oil, and oil slurry. The overhead condenser is in fluid communication with the fractionator and is configured to receive the vapor product stream and produce a first cooling fluid stream having a temperature ranging from about 105 degrees Fahrenheit (°F) to about 120 °F. The cooler in the gas concentration unit is in fluid communication with the overhead condenser and is configured to receive the first cooling fluid stream and produce a second cooling fluid stream having a temperature ranging from about 55 °F to about 100 °F. The receiver in the gas concentration unit is in fluid communication with the cooler and is configured to receive the second cooling fluid stream and separate the second cooling fluid stream into a wet gas stream containing ethylene and propylene and a second crude naphtha stream. The wet gas compressor in the gas concentration unit is in fluid communication with the receiver and is configured to increase a pressure of the wet gas stream containing ethylene and propylene for use in downstream processing to produce an enriched olefin product stream. In certain embodiments, the wet gas compressor can increase the pressure of the wet gas stream from 20 pounds per square inch gauge (psig) to 225 psig for use in downstream processing. In certain embodiments, the temperature of the first cooling fluid stream can range from about 105 °F to about 115 °F. In certain embodiments, the temperature of the second cooling fluid stream can range from about 55 °F to about 75 °F or from about 55 °F to about 65 °F. In certain embodiments, the riser reactor is configured to receive two or more hydrocarbon feedstock streams and a catalyst. In certain embodiments, the volumetric flow of the wet gas stream decreases by about 35% by volume when the temperature of the first cooling fluid stream decreases from about 105 °F to about 60 °F.

[0008] Another embodiment of an olefin production system includes a fluid catalytic cracking unit containing (i) a riser reactor configured to receive a hydrocarbon feed stream and a catalyst and produce a cracked product stream containing light and heavy paraffins, naphtha, aromatics, and olefins, and a spent catalyst; (ii) a regenerator in communication with the riser reactor and configured to receive the spent catalyst and regenerate the spent catalyst to produce an entrained catalyst containing an inert material entrained with the regenerated catalyst; (iii) a stripper in communication with the regenerator and configured to receive the entrained catalyst and produce the regenerated catalyst by removing the inert material contained within the entrained catalyst; (iv) a conduit for supplying the regenerated catalyst to the riser reactor. The system also includes a fractionator in fluid communication with the fluid catalytic cracking unit and configured to receive the cracked product stream and separate it into (i) a vapor product stream containing ethylene and propylene and light naphtha, (ii) a first crude naphtha product stream, and (iii) a liquid product stream containing one or more of heavy naphtha, light cycle oil, and oil slurry. The system also includes a vapor recovery unit in fluid communication with the fractionator and configured to receive the vapor product stream and produce an olefin-rich product stream. In certain embodiments, the riser reactor is a dual or multiple riser reactor. In certain embodiments, the regenerated catalyst is produced by removing about 75 percent of the inert material contained within the entrained catalyst. In certain embodiments, the regenerated catalyst is produced by removing about 85 percent of the inert material contained within the entrained catalyst. In certain embodiments, the riser reactor is configured to receive two or more hydrocarbon feed streams and catalyst. In certain embodiments, the riser reactor includes a quench line to introduce a quench fluid into the riser reactor 1.5 seconds after the hydrocarbon feed stream contacts the catalyst.

[0009] Another embodiment of an olefin production system includes a fluid catalytic cracking unit containing (i) a riser reactor configured to receive a hydrocarbon feed stream and a catalyst and produce a cracked product stream containing light and heavy paraffins, naphtha, aromatics, and olefins, and a spent catalyst; (ii) a regenerator in communication with the riser reactor and configured to receive the spent catalyst and regenerate the spent catalyst to produce an entrained catalyst containing an inert material entrained with the regenerated catalyst; (iii) a stripper in communication with the regenerator and configured to receive the entrained catalyst and produce the regenerated catalyst by removing the inert material contained within the entrained catalyst; (iv) a conduit for supplying the regenerated catalyst to the riser reactor. The system can also include a fractionator in fluid communication with the fluid catalytic cracking unit and configured to receive the cracked product stream and separate it into (i) a vapor product stream containing ethylene and propylene and light naphtha, (ii) a first crude naphtha product stream, and (iii) a liquid product stream containing one or more of heavy naphtha, light cycle oil, and oil slurry. The system can also include a gas concentration unit containing an overhead condenser, a cooler, a receiver, and a wet gas compressor. The overhead condenser is in fluid communication with the fractionator and configured to receive the vapor product stream and produce a first cooled fluid stream having a temperature ranging from about 105 °F to about 120 °F. The cooler in the gas concentration unit is in fluid communication with the overhead condenser and configured to receive the first cooled fluid stream and produce a second cooled fluid stream having a temperature ranging from about 55 °F to about 100 °F. The receiver in the gas concentration unit is in fluid communication with the cooler and configured to receive the second cooled fluid stream and separate it into a wet gas stream containing ethylene and propylene and a second crude naphtha stream. The wet gas compressor in the gas concentration unit can be in fluid communication with the receiver and configured to increase a pressure of the wet gas stream containing ethylene and propylene for use in downstream processing to produce an enriched olefin product stream. In certain embodiments, the wet gas compressor can increase the pressure of the wet gas stream from 20 pounds per square inch gauge (psig) to 225 psig for use in downstream processing. In certain embodiments, the temperature of the first cooled fluid stream can range from about 105 °F to about 115 °F. In certain embodiments, the temperature of the second cooled fluid stream can range from about 55 °F to about 75 °F or from about 55 °F to about 65 °F. In certain embodiments, the riser reactor is configured to receive two or more hydrocarbon feed streams. In certain embodiments, the riser reactor is a dual or multiple riser reactor. In certain embodiments, a volumetric flow rate of the wet gas stream decreases by about 35% by volume when the temperature of the first cooled fluid stream decreases from about 105 °F to about 60 °F. In certain embodiments, the regenerated catalyst is produced by removing about 75% of the inert material contained within the entrained catalyst.In some embodiments, the regenerated catalyst is produced by removing approximately 85 percent of the inert material contained within the entrained catalyst. In some embodiments, the riser reactor includes a quench line for introducing quench fluid into the riser reactor to reduce the contact time between one of two or more hydrocarbon feed streams and the catalyst by 0.5 seconds or more.

[0010] Delineating a gas unit can involve reducing the load on a gas concentrator (GCU), including a wet gas compressor. The combination of MAXOFIN™ technology and reduced load on the wet gas compressor can maximize propylene yield at the gas unit. This disclosure generally relates to several embodiments of methods and systems for delineating a gas unit to increase propylene yield during FCCU retrofitting. Attached Figure Description

[0011] These embodiments and other features, aspects, and advantages of this disclosure will be better understood in conjunction with the following description, claims, and accompanying drawings. However, it should be noted that the drawings illustrate only certain embodiments of this disclosure and should therefore not be construed as limiting the scope of this disclosure.

[0012] Figure 1 This is an illustrative flowchart of an olefin generation system according to an embodiment of the present disclosure, the olefin generation system having an FCCU for defining a wet gas compressor and a cooler system in a gas concentration unit.

[0013] Figure 2 This is an illustrative flow diagram of a catalytic cracking unit having a regenerator and a stripping tower according to embodiments of the present disclosure.

[0014] Figure 3 This is an illustrative flowchart of a catalytic cracking unit having a regenerator and a quencher according to an embodiment of the present disclosure.

[0015] Figure 4 This is an illustrative flow diagram of an olefin generation system according to an embodiment of the present disclosure, the olefin generation system having (i) a catalytic cracking unit with a regenerator and a stripping tower and (ii) a cooler in a gas concentration unit for defining a wet gas compressor. Detailed Implementation

[0016] To provide a more detailed understanding of embodiments of the methods and systems disclosed herein, as well as other features and advantages that will become apparent therefrom, a more specific description of embodiments of the methods and systems is provided. Numerous details are set forth in the following description to provide a thorough understanding of the various embodiments. In other instances, well-known processes, apparatuses, and systems may not be described in particular detail to avoid unnecessarily obscuring the various embodiments. Additionally, the illustrations of the various embodiments may omit certain features or details to avoid obscuring the various embodiments.

[0017] This document provides several methods and systems, which can be implemented individually or in various combinations, for defining gaseous units in olefin generation systems to facilitate higher propylene yields. Hydrocarbon feedstocks can consist of heavy feedstocks, including heavy atmospheric gas oil, vacuum gas oil, deasphalted oil (DAO), and / or atmospheric residue. Hydrocarbon feedstocks can also consist of light hydrocarbon feedstocks, including light alkanes, cycloalkanes, or alkenes. The FCCC unit can be used to facilitate the cracking of hydrocarbon feedstocks to convert them into valuable products such as ethylene and propylene. Existing FCC units can be retrofitted, or new base-level FCC units can be designed using improved technologies, including, but not limited to, the MAXOFIN™ technology available from KBR, to produce light olefins, such as ethylene and propylene, from light naphtha streams. The MAXOFIN™ technology is a process that enables refineries to maximize propylene production by 20% or more using ethylene produced with significantly lower levels of conventional steam cracking. The olefin generation system comprises three main sections: an FCCU section, a main fractionator section, and a gas unit section, which may include a gas concentration unit (GCU) within a larger vapor recovery unit (VRU). In some embodiments, the olefin generation system is a unit utilizing MAXOFIN™ technology. The GCU may include an overhead condenser, cooler, receiver, and wet gas compressor, and is in fluid communication with other equipment, such as stripping columns and main absorbers, that can be used to process valuable products.

[0018] In this article, the terms "heavy naphtha" or "full-range naphtha" refer to a mixture of C6 and higher hydrocarbons with a boiling range of approximately 340°F to 460°F; "crude naphtha" refers to a mixture of C6 and higher hydrocarbons with some lighter components and a boiling range of approximately 330°F to 415°F; and "light naphtha" refers to a mixture of C5 and higher hydrocarbons with a boiling range of approximately 120°F to 350°F.

[0019] The term "about" refers to a range of values ​​that include a specified value, which a person skilled in the art will consider reasonably similar to the specified value. In embodiments, "about" refers to a value within a standard deviation using a measurement generally acceptable in the art. In a non-limiting embodiment, when the term "about" is used with a specific value, then "about" refers to a range extending to ±10% of the specified value, alternatively ±5% of the specified value, alternatively ±1% of the specified value, or alternatively ±0.5% of the specified value. In embodiments, "about" refers to the specified value.

[0020] The term “rich in” component refers to a stream containing more than about 10% by weight, or more than about 15% by weight, or more than about 20% by weight, or more than about 25% by weight, or more than about 30% by weight of that component.

[0021] Examples include an olefin production system for defining a wet gas compressor in a gas concentration unit. One such system includes an FCCU, a fractionator, an overhead condenser, and a gas concentration unit with a cooler, a receiver, and a wet gas compressor. The FCCU contains a riser reactor and a regenerator. Gas plant design and operating conditions may include riser reactors with two, three, four, or even more risers. Hydrocarbon feedstock is supplied to the FCCU and converted into a cracking product stream containing light and heavy alkanes, naphtha, aromatics, and alkenes. In some embodiments, the riser reactor is configured to receive two or more different hydrocarbon feedstock streams and catalyst. The riser reactor in the FCCU may include a quench line to introduce quench fluid into the riser reactor 1.5 seconds after the hydrocarbon feedstock contacts the catalyst. This interaction allows for a specific product profile in the cracking product stream, such as an increase in olefin yield. The fractionator is in fluid communication with the fluidized catalytic cracking unit and is configured to receive the cracking product stream and separate it into (i) a vapor product stream containing ethylene and propylene as well as light naphtha, (ii) a first crude naphtha product stream, and (iii) a liquid product stream containing one or more of heavy naphtha, light cycle oil, and slurry. The overhead condenser is in fluid communication with the fractionator and is configured to receive the vapor product stream and generate a first cooling fluid stream. In some embodiments, the first cooling fluid stream has a temperature ranging from about 105 °C to about 120 °C. In some embodiments, the temperature range of the first cooling fluid stream may be from about 100 °C to about 120 °C, or from about 105 °C to about 115 °C, or from about 100 °C to about 115 °C, or from about 100 °C to about 110 °C. A cooler in the gas concentration unit is in fluid communication with the overhead condenser and is configured to receive the first cooling fluid stream and generate a second cooling fluid stream. In some embodiments, the second cooling fluid stream has a temperature ranging from about 55°F to about 100°F. In some embodiments, the temperature of the first cooling fluid stream can range from about 55°F to about 90°F, or from about 55°F to about 85°F, about 55°F to about 75°F, or about 55°F to about 65°F. A receiver in the gas concentration unit is in fluid communication with the cooler and is configured to receive the second cooling fluid stream and separate it into a wet gas stream containing ethylene and propylene and a second crude naphtha stream. A wet gas compressor in the gas concentration unit is in fluid communication with the receiver and is configured to increase the pressure of the wet gas stream containing ethylene and propylene for supply to downstream processing. In some embodiments, the wet gas compressor can increase the pressure of the wet gas stream from about 20 psig to about 225 psig for supply to downstream processing. In some embodiments, the volumetric flow rate of the wet gas stream decreases by about 35% when the temperature of the first cooling fluid stream decreases from about 105°F to about 60°F.In some embodiments, the introduction of a cooler results in a reduction of the volumetric flow rate of the wet gas stream by about 5% by volume, or about 10% by volume, or about 15% by volume, or about 17% by volume, or about 20% by volume, or about 25% by volume, or about 30% by volume, or about 40% by volume. In some embodiments, the system described herein can result in an increase in propylene yield of at least 3% by weight, or about 4% by weight, or about 5% by weight, or about 5.5% by weight, or about 6% by weight, or about 6.5% by weight, or about 7% by weight, or about 8% by weight, or about 10% by weight, or about 15% by weight, or about 20% by weight.

[0022] Figure 1 This is an illustrative flow diagram of an olefin generation system according to embodiments of the present disclosure, the system having an FCCU (Fuel Concentration Unit) for defining a wet gas compressor and a cooler system in a gas concentration unit. In some embodiments, the olefin generation system 100 includes a fluidized catalytic cracking unit 130 having a reactor and a regenerator 102 with dual risers 104, 106. In such embodiments, two or more hydrocarbon feed streams 101 and 103 are received by the dual risers 104 and 106, respectively. The two or more hydrocarbon feed streams may be the same or different feed streams. The dual risers 104, 106 allow the generation of a cracking product stream 105. The cracking product stream 105 contains light and heavy alkanes, naphtha, aromatics, and alkenes. The olefin generation system 100 further includes a fractionator 114 in fluid communication with the fluidized catalytic cracking unit 130. Fractionator 114 is configured to receive cracked product stream 105 from dual risers 104, 106 and separate cracked product stream 105 into (i) a vapor product stream 111 containing ethylene and propylene as well as light naphtha, (ii) a first crude naphtha product stream 109, and (iii) a liquid product stream 107 containing one or more of heavy naphtha, light circulating oil, and slurry. Olefin generation system 100 includes a gas condenser (GCU) containing one or more of an overhead condenser 116, a cooler 118, a receiver 120, and a wet gas compressor 122. Overhead condenser 116 is in fluid communication with fractionator 114 and is configured to receive vapor product stream 111 from fractionator 114 and generate a first cooling fluid stream 113 having a temperature ranging from about 105 °F to about 115 °F. Cooler 118 is in fluid communication with overhead condenser 116 and is configured to receive a first cooling fluid flow 113 from overhead condenser 116 and generate a second cooling fluid flow 115 having a temperature ranging from about 60℉ to about 100℉. The cooler reduces the temperature of the inlet flow to the downstream processing unit within the GCU, which results in a reduction in the volumetric flow rate through the downstream processing unit.

[0023] The olefin generation system 100 further includes a receiver 120 in fluid communication with a cooler 118. The receiver 120 is configured to receive a second cooling fluid flow 115 from the cooler 118 and process the second cooling fluid flow 115 into a wet gas flow 117 containing ethylene and propylene and a second crude naphtha flow.

[0024] The olefin generation system 100 also includes a wet gas compressor 122 in fluid communication with a receiver 120. The wet gas compressor 122 is configured to receive a wet gas stream 117 from the receiver 120 and increase the pressure of the wet gas stream 117, containing ethylene and propylene, such as from 20 psig to 225 psig. This wet gas stream 119 at the increased pressure is supplied for downstream processing. The volumetric flow rate of the wet gas stream 117 through the wet gas compressor 122 is reduced when the cooler 118 lowers the temperature of the wet gas stream 117 fed to the wet gas compressor 122. The GCU may include a suction drum. The suction drum is configured to receive the wet gas stream 117 from the receiver 120 and separate heavier components from the wet gas stream 117 before it is supplied to the wet gas compressor 122. The pressure conditions of the wet gas stream 117 supplied to the wet gas compressor 122 may be equal to or equivalent to the pressure of a wet gas stream supplied to a compressor in a standard GCU without a cooler. The temperature of the wet gas stream 117 is significantly lower than that of the wet gas stream supplied to the compressor in a standard GCU without a cooler. The amount of reduction in volumetric flow rate can depend on the type of FCCU used with different hydrocarbon feedstocks, operating conditions such as pressure and temperature, and other processing conditions applied to the GCU. As a non-limiting example, when the temperature of the wet gas stream generated in the system described herein is reduced from about 100℉ to about 60℉, the volumetric flow rate is reduced by 35% compared to the wet gas processed in a standard GCU without a cooler. As a non-limiting example, based on modeling data, the propylene yield increases by at least about 6.6 wt% (w / w) due to the reduced suction flow rate of the wet gas stream generated in the system described herein.

[0025] The embodiments also include a method for defining a gas unit during FCCU unit retrofitting using a cooler system downstream of a fractionation column overhead condenser. One such method for defining a gas unit during FCCU retrofitting involves directing a hydrocarbon feed stream to a riser reactor of the FCCU. The riser reactor produces a cracking product stream. The method further includes directing the cracking product stream from the riser reactor to a fractionator to produce a vapor product stream, a first crude naphtha stream, and a liquid product stream. The method may further involve the step of directing the vapor product stream from the fractionator to a GCU containing an overhead condenser, a cooler, a receiver, and a wet gas compressor. The overhead condenser and cooler reduce the temperature and flow rate of the vapor product stream. Reducing the temperature of the vapor product stream may also involve directing the vapor product stream from the fractionator to the overhead condenser to produce a first cooling fluid stream. The first cooling fluid stream may have a temperature ranging from about 100°F to about 120°F. The method further includes directing the first cooling fluid stream from the overhead condenser to a cooler to produce a second cooling fluid stream. The second cooling fluid flow can have a temperature ranging from about 55℉ to about 100℉. The method further includes directing the second cooling fluid flow from the cooler to a receiver to generate a humid gas flow; and directing the humid gas flow from the receiver to a humid gas compressor to generate a humid gas flow under increased pressure for downstream processing. The temperature reduction of the humid gas flow before it is supplied to the humid gas compressor also reduces the suction flow rate of the humid gas compressor.

[0026] Riser reactors may include two, three, four, or even more. In some embodiments, riser reactors are configured to receive two or more hydrocarbon feed streams. Each riser reactor may receive one of two or more hydrocarbon feed streams. The two or more hydrocarbon feed streams may be the same or different feed streams.

[0027] Figure 2This is an illustrative flow diagram of a catalytic cracking unit with a regenerator and a stripping tower according to embodiments of the present disclosure, which facilitates a wet gas compressor in a gas concentration unit defining an olefin production system 200. The olefin production system 200 includes a fluidized bed catalytic cracking unit 230 having dual riser reactors 204, 206. The reactors with dual risers 204, 206 are configured to receive two or more hydrocarbon feedstock streams 201, 203 and catalyst to produce a cracking product stream 205 containing light and heavy alkanes, naphtha, aromatics, and alkenes, as well as spent catalyst. The fluidized bed catalytic cracking unit 230 further includes a regenerator 202 in communication with the dual riser reactors 204, 206. The regenerator 202 is configured to receive spent catalyst from the dual riser reactors 204, 206 and regenerate the spent catalyst to produce an entrained catalyst containing an inert material entrained with the regenerated catalyst. Regenerator 202 can operate in a temperature range of about 1250 °F to about 1400 °F and a pressure range of about 35 psig to about 55 psig. Fluidized catalytic cracking unit 230 also includes stripping columns 224, 226 disposed downstream of regenerator 202. Stripping columns 224, 226 are configured to receive entrained catalyst from dual riser reactors 204, 206 and generate regenerated catalyst by removing inert material contained within the entrained catalyst. The stripping columns can operate in a temperature range of about 1250 °F to about 1400 °F and a pressure range of about 35 psig to about 55 psig at or near the temperature and pressure of the regenerator. The stripping columns may contain structured packing and / or steam / gas stripping media. Air, steam, nitrogen, or similar stripping gases can be supplied to the stripping columns to remove inert material or other materials from the entrained catalyst. This embodiment may include a single stripping column supplying regenerated catalyst to two risers. Inert substances are combustion products generated from the combustion of carbonaceous deposits on spent catalysts, depending on the reactivity of the compounds with the catalyst under FCC conditions. Inert substances may include carbon oxides, hydrogen sulfide, sulfur oxides, water, and nitrogen. The fluidized catalytic cracking unit 230 further includes conduits for supplying regenerated catalyst to risers 204, 206 of the dual riser reactor. The olefin generation system 200 further includes a fractionator 214 in fluid communication with the fluidized catalytic cracking unit 230. The fractionator 214 is configured to receive the cracking product stream 205 and separate the cracking product stream 205 into (i) a vapor product stream 211 containing ethylene and propylene as well as light naphtha, (ii) a first crude naphtha product stream 209, and (iii) a liquid product stream 207 containing one or more of heavy naphtha, light cycle oil, and slurry. The olefin generation system 200 also includes a vapor recovery unit 216 in fluid communication with the fractionator 214. The vapor recovery unit is configured to receive a vapor product stream 211 from the fractionator 214 and produce an olefin-rich product stream 213.Based on FCC modeling data, in addition to regenerating the spent catalyst through a regenerator, using a stripping tower to remove inert substances contained in the entrained catalyst can increase propylene yield by at least 1.15% by weight.

[0028] The embodiments also include methods for defining the gas unit using a regenerator and stripping tower during FCCU unit retrofitting, such as Figure 2 The system described herein. One such method for defining a gas unit during FCCU retrofitting involves directing a hydrocarbon feedstock stream and catalyst to a riser reactor. In the riser reactor, the hydrocarbon feedstock is subjected to fluidized catalytic cracking to produce a cracking product stream and spent catalyst. The method further includes directing the cracking product stream from the riser reactor to a fractionator to produce a vapor product stream, a first crude naphtha stream, and a liquid product stream. The method may further include directing the vapor product stream to a steam recovery unit to produce an olefin-rich product stream. The method includes directing the spent catalyst to a regenerator to regenerate the spent catalyst to produce entrained catalyst. The method further includes directing the entrained catalyst to a stripper to produce regenerated catalyst. In some embodiments, the regenerated catalyst is produced by removing approximately 40 percent of the inert material contained within the entrained catalyst. In some embodiments, the regenerated catalyst is produced by removing approximately 50%, or approximately 60%, or approximately 65%, or approximately 70%, or approximately 75%, or approximately 80%, or approximately 85% of the inert material contained within the entrained catalyst. In some embodiments, the catalyst regeneration is achieved by removing substantially all inert material contained within the entrained catalyst. In some embodiments, the systems and methods described herein can result in an increase in propylene yield of at least 0.5 wt%, or about 0.75 wt%, or about 1 wt%, or about 1.15 wt%, or about 1.2 wt%, or about 1.5 wt%, or about 1.75 wt%, or about 2 wt%, or about 3 wt%, or about 3.5 wt%.

[0029] Figure 3This is an illustrative flow diagram of a catalytic cracking system with a regenerator and quench lines according to embodiments of the present disclosure, which facilitates a wet gas compressor in a gas concentration unit defining an olefin production system 300. In some embodiments, the olefin production system 300 includes a fluidized bed catalytic cracking unit 330 with dual riser reactors 304, 306. The reactors with dual risers 304, 306 are configured to receive two or more hydrocarbon feedstock streams 301, 303 and a catalyst to produce a cracked product stream 305 containing light and heavy alkanes, naphtha, aromatics, and alkenes. The two or more hydrocarbon feedstock streams can be the same or different feedstocks. The dual risers 304, 306 are configured to include two quench lines 308, 310 to reduce catalytic reaction between the hydrocarbon feedstock and the catalyst by introducing a quench fluid. The quench fluid can be heavy naphtha and distillate oil. The quench fluid is inert to cracking, for example, water, steam, or selected hydrocarbons. In some embodiments, the contact time between the hydrocarbon feedstock streams 301, 303 and the catalyst in the riser has been considered by introducing a quench fluid at a contact time of 1.5 seconds (compared to a baseline contact time of 2 seconds) after the hydrocarbon feedstock has contacted the catalyst along the riser. The contact time can depend on the riser size and the flow rate of the hydrocarbon feedstock through the riser. The introduction of the quench fluid results in a reduction in dry gas generation and unloading of the wet gas compressor. The riser contact time can also be reduced by hardware modifications to the riser size. Contact times for different riser sizes can be developed using modeling principles applicable to FCC reactions. The fluidized catalytic cracking unit 330 includes a regenerator 302 in communication with the dual riser reactors 304, 306. The regenerator 302 is configured to receive spent catalyst from the dual risers 304, 306 and regenerate the spent catalyst to produce regenerated catalyst. The fluidized catalytic cracking unit 330 further includes a conduit for supplying the regenerated catalyst to the risers of the dual riser reactors 304, 306. The olefin generation system 300 also includes a fractionator 314 in fluid communication with the fluidized catalytic cracking unit 330. The fractionator 314 is configured to receive a cracking product stream 305 and separate it into (i) a vapor product stream 311 containing ethylene and propylene as well as light naphtha, (ii) a first crude naphtha product stream 309, and (iii) a liquid product stream 307 containing one or more of heavy naphtha, light cycle oil, and slurry. The olefin generation system 300 further includes a vapor recovery unit 316 in fluid communication with the fractionator 314. The vapor recovery unit is configured to receive the vapor product stream 311 from the fractionator 314 and produce an olefin-rich product stream 313. As a non-limiting example, based on FCC modeling data, the propylene yield increased by at least about 3.30% by weight due to the reduced reaction between the hydrocarbon feedstock and the catalyst in the system described herein.

[0030] The embodiments also include methods for defining gas units, regenerators, and quench lines during FCCU unit retrofitting. One such method for defining gas units during FCCU retrofitting involves directing a hydrocarbon feedstock stream and catalyst to a riser reactor. In the riser reactor, the hydrocarbon feedstock is subjected to fluidized catalytic cracking to produce a cracking product stream and spent catalyst. The method may further include directing quench fluid from a quench line connected to the riser reactor approximately 1.5 seconds after the hydrocarbon feedstock contacts the catalyst to reduce the contact time between the hydrocarbon feedstock and the catalyst. The method further includes directing the cracking product stream from the riser reactor to a fractionator to produce a vapor product stream, a first crude naphtha stream, and a liquid product stream. The method may further include directing the vapor product stream to a vapor recovery unit to produce an olefin-rich product stream. In some embodiments, the systems and methods described herein can result in an increase in propylene yield of at least 1 wt%, or about 1.5 wt%, or about 2 wt%, or about 2.25 wt%, or about 2.5 wt%, or about 3 wt%, or about 3.1 wt%, or about 3.2 wt%, or about 3.3 wt%, or about 3.5 wt%, or about 4 wt%, or about 4.5 wt%, or about 5 wt%, or about 6 wt%.

[0031] Examples of olefin generation systems include a modified FCCU comprising a riser reactor, a regenerator, and a stripper. The riser reactor is configured to receive a hydrocarbon feedstock stream and catalyst and produce a cracked product stream containing light and heavy alkanes, naphtha, aromatics, and alkenes, as well as spent catalyst. The regenerator is in communication with the riser reactor and configured to receive and regenerate the spent catalyst to produce entrained catalyst containing inert material entrained with the regenerated catalyst. The stripper is configured to be in communication with the regenerator and to receive the entrained catalyst and produce regenerated catalyst by removing the inert material contained within the entrained catalyst; and a conduit for supplying the regenerated catalyst to the riser reactor. In some embodiments, a fractionator is in fluid communication with the fluidized catalytic cracking unit and configured to receive the cracked product stream and separate it into (i) a vapor product stream containing ethylene and propylene and light naphtha, (ii) a first crude naphtha product stream, and (iii) a liquid product stream containing one or more of heavy naphtha, light cycle oil, and slurry. In some embodiments, the vapor recovery unit is in fluid communication with the fractionator and configured to receive the vapor product stream and generate an olefin-rich product stream. In some embodiments, the riser may include a quench line to introduce quench fluid into the riser reactor after the hydrocarbon feed stream has contacted the catalyst. In some embodiments, the quench fluid is introduced to reduce the reaction time of the fluid cracking of the hydrocarbon feed stream by 10%, 20%, or 30% to achieve a specific product distribution in the cracked product stream. Compared to a basic reaction time of 2 seconds, the quench fluid can be added 1.5 seconds after the hydrocarbon feed stream has contacted the catalyst.

[0032] In some embodiments, the riser reactor is configured to receive two or more hydrocarbon feed streams and a catalyst. The riser reactor may include two, three, four, or even more riser reactors. In some embodiments, the riser reactor is configured to receive two or more hydrocarbon feed streams. Each riser reactor may receive one of the two or more hydrocarbon feed streams. The two or more hydrocarbon feed streams may be the same or different feed streams.

[0033] Figure 4 This is an illustrative flow diagram of an olefin production system 400 according to an embodiment of the present disclosure, the olefin production system having a catalytic cracking unit 430 with a regenerator, a stripping tower, and a cooler system in a gas concentration unit for defining a wet gas compressor. The fluidized bed cracking unit 430 includes dual riser reactors 404, 406 configured to receive two or more hydrocarbon feedstocks 401, 403 and a catalyst to produce a cracking product stream 405 containing light and heavy alkanes, naphtha, aromatics and alkenes, and spent catalyst. The dual riser reactors 404, 406 are configured to include two quench lines 408, 410 for reducing the catalytic reaction between the hydrocarbon feedstocks 401, 403 and the catalyst by introducing quench fluid. The fluidized bed cracking unit 430 further includes a regenerator 402 in communication with the dual risers 404, 406. Regenerator 402 is configured to receive spent catalyst from dual riser reactors 404 and 406 to regenerate the spent catalyst and produce entrained catalyst containing inert material entrained with the regenerated catalyst. Fluid cracking unit 430 also includes stripping columns 424 and 426 in communication with regenerator 402. The stripping columns are configured to receive the entrained catalyst from regenerator 402 and produce regenerated catalyst by removing the inert material contained within the entrained catalyst. Fluid cracking unit 430 further includes conduits for supplying the regenerated catalyst to risers 404 and 406. The regenerated catalyst, along with two or more hydrocarbon feedstocks, can be used to generate cracking product streams.

[0034] The olefin generation system 400 further includes a fractionator 414 in fluid communication with the fluidized catalytic cracking unit 430. The fractionator 414 is configured to receive a cracking product stream 405 from the dual risers 404 and 406 and separate the cracking product stream 405 into (i) a vapor product stream 411 containing ethylene, propylene, and light naphtha, (ii) a first crude naphtha product stream 409, and (iii) a liquid product stream 407 containing one or more of heavy naphtha, light cycle oil, and slurry. The olefin generation system 400 also includes an overhead condenser 416 in fluid communication with the fractionator 414. The overhead condenser 416 is configured to receive the vapor product stream 411 from the fractionator 414 and generate a first cooling fluid stream 413 having a temperature ranging from about 100 °F to about 120 °F. The olefin generation system 400 further includes a cooler 418 in fluid communication with the overhead condenser 416. Cooler 418 is configured to receive a first cooling fluid stream 413 from overhead condenser 416 and produce a second cooling fluid stream 415 having a temperature ranging from about 60°F to about 100°F. The olefin production system 400 also includes a receiver 420 in fluid communication with cooler 418. Receiver 420 is configured to receive the second cooling fluid stream 415 from cooler 418 and separate the second cooling fluid stream 415 into a wet gas stream 417 containing ethylene and propylene and a second crude naphtha stream 423. Olefin production system 400 includes a wet gas compressor 422 in fluid communication with receiver 420. Wet gas compressor 422 is configured to receive the wet gas stream 417 from receiver 420 and increase the pressure of the wet gas stream 417 containing ethylene and propylene for supply to downstream processing 419. In some embodiments, the pressure of the wet gas stream is increased from 20 psig to 225 psig for supply to downstream processing.

[0035] The embodiments also include methods for defining a gas unit using a cooler system on the top condenser of a fractionation column during FCCU unit retrofitting. One such method for defining a gas unit during FCCU retrofitting involves directing a product stream rich in ethylene, propylene, or combinations thereof from a fluidized catalytic cracking unit to a fractionator. The fluidized catalytic cracking unit may include a single riser or dual or multiple risers. For example, MAXOFIN™ technology uses a dual riser system that maximizes propylene production by 20% or more while reducing ethylene production. MAXOFIN™ technology has proven to be more efficient than conventional steam cracking. Additionally, MAXOFIN™ technology provides refineries with the flexibility to operate in different modes of operation depending on market demand. Different operating modes include operating as a conventional FCC system to produce gasoline, or operating as a propylene FCC system to produce additional propylene. In some embodiments, the gas unit design and operating conditions include riser reactors with two, three, four, or even more risers.

[0036] Different hydrocarbon feedstocks can be cracked in a fluidized bed catalytic cracking unit to produce a first effluent and a second effluent. For example, a hydrocarbon feedstock containing heavy oil is supplied to a first riser, and a hydrocarbon feedstock containing light oil is supplied to a second riser. Additives can be added to the first and second risers. In some embodiments, proprietary MAXOFIN™ additives available from KBR can be added. Therefore, MAXOFIN™ additives can provide additional benefits for propylene production. In some embodiments, the catalyst comprises an FCC base catalyst and a ZSM additive catalyst. Crystalline aluminosilicates for cracking light hydrocarbon feedstocks are exemplified by ZSM-5 and similar catalysts. In some embodiments, CO promoters, sulfur oxides (SO₄) can be added. X One or more of the additives and / or other additives are added to the regenerator, which may later be conveyed to the riser. In some embodiments, the catalyst is heated.

[0037] In some embodiments, the conditions of the first riser and the second riser are different. Different conditions may include temperature, catalyst-to-oil ratio, hydrocarbon partial pressure, vapor-to-oil ratio, residence time, or combinations thereof. In another embodiment, the conditions of the first riser and the second riser are the same. In some embodiments, the first effluent and the second effluent from the first riser and the second riser are the same. In other embodiments, the first effluent and the second effluent are different due to the introduction of different feedstocks or due to different operating conditions. In some embodiments, the method further involves treating the first effluent and the second effluent in a fractionator to fractionate them into several product streams. In some embodiments, the fractionator may have a top pressure of about 25 psig and a top temperature of about 250℉. The product streams may include (1) a vapor product stream comprising fuel gas, C3, isobutylene (C4), and light naphtha, (2) a crude naphtha product stream, and (3) a fractionator liquid product stream containing one or more of heavy naphtha, light circulating oil, and slurry.

[0038] The method may further involve directing a vapor product stream to a gas concentration unit containing an overhead condenser, a cooler, a receiver, and a wet gas compressor. The overhead condenser and cooler reduce the temperature and flow rate of the vapor product stream. Reducing the temperature of the vapor product may also involve directing the vapor product stream from a fractionator to the overhead condenser, thereby reducing the stream temperature to approximately 120°F, or approximately 115°F, or approximately 110°F, or approximately 105°F, or approximately 100°F. Reducing the temperature of the vapor product may involve directing the vapor product stream from the overhead condenser to a cooler system to reduce the stream temperature by 90°F, or approximately 80°F, or approximately 75°F, or approximately 65°F, or approximately 62°F, or approximately 60°F, or approximately 55°F. The overhead condenser may influence the cooler configuration. The cooler system may have a residence time depending on the physical dimensions and cooling capacity of the cooler system. The cooler system is rated based on the cooling load. The method may further involve directing a cooling fluid stream to a receiver and a wet gas compressor. The reduction in the suction temperature of the wet gas compressor also reduces the suction flow rate of the wet gas compressor. In some embodiments, the introduction of a cooler results in a reduction in the volumetric flow rate of the wet gas stream at the wet gas compressor of approximately 5% by volume, or approximately 10% by volume, or approximately 15% by volume, or approximately 17% by volume, or approximately 20% by volume, or approximately 25% by volume, or approximately 30% by volume, or approximately 40% by volume, or approximately 42% by volume, or approximately 45% by volume. In a non-limiting example, for a temperature reduction from approximately 105 °F to approximately 60 °F, the volumetric flow rate at the wet gas compressor can be reduced by 40 percent.

[0039] Examples include methods for reducing entrained inert material in a regenerator catalyst stripping column to define a gaseous unit during FCCU retrofitting. In one example, the method for defining a gaseous unit during FCC unit retrofitting involves guiding spent catalyst from a riser in a fluidized catalytic cracking unit to a regenerator. The regenerator produces entrained catalyst containing inert material entrained with regenerated catalyst. Removing inert material from the entrained catalyst increases propylene yield. Steam can be introduced into a stripping column downstream of the regenerator to remove the entrained inert material. The stripping column may have angled and oriented baffles to provide uniform flow on the baffles and increase the contact time between the catalyst and the steam. The stripping column may have a residence time of about 20 seconds to about 50 seconds. The stripping column may operate at or near the temperature and pressure of the regenerator. The residence time provides maximum mass transfer surface area and higher entrained inert material removal efficiency. The removal rate of entrained inert material from the regenerated catalyst can be up to 85%. The structured packing and stripping medium in the stripping tower will determine the amount of inert material that can be removed. The catalyst contact time can be approximately 30 seconds.

[0040] This method may further involve directing the vapor product stream from the fractionator to a gas concentration unit. The method may also involve directing the fractionator vapor product stream from the fractionator overhead condenser to a wet gas compressor. The removal of entrained inert materials can reduce the residue in the fluidized catalytic cracking unit. This reduction in entrained inert material residue can also reduce the load on the wet gas compressor. In some embodiments, the reduced load on the wet gas compressor leads to an increase in propylene yield.

[0041] Examples include methods for defining a gaseous unit by introducing a quench line to reduce the contact time between the hydrocarbon feedstock and the catalyst in the riser reactor during FCCU retrofitting. In one example, defining the gaseous unit during FCCU retrofitting may involve guiding a first hydrocarbon feedstock and a first catalyst into a first riser. The first riser may have a quench line for introducing quench fluid to contact the first hydrocarbon feedstock and the first catalyst. In some embodiments, the method may also involve quenching the first hydrocarbon feedstock using a quenching agent during a 1.5-second first riser contact time after the first hydrocarbon feedstock and the first catalyst are introduced into the first riser. In other embodiments, the riser contact time may be reduced by alternative hardware modifications to the fluidized catalytic cracking unit. In one embodiment, the method may further involve guiding a second hydrocarbon feedstock and a second catalyst into a second riser. The second riser may have a quench line for introducing quench fluid to contact the second hydrocarbon feedstock and the second catalyst. In another example, the method may also involve quenching the second hydrocarbon feedstock using a quenching agent during a 1.5-second first riser contact time after the second hydrocarbon feedstock and the second catalyst are introduced into the second riser. In other embodiments, a quench fluid may be included compared to an FCCU without the quench line to reduce the contact time in the riser by at least 0.5 seconds. Alternatively, as described herein, alternative riser improvements may be used to reduce the riser contact time for the first and second hydrocarbon feedstocks.

[0042] Some embodiments include an olefin production method using the following steps: (i) guiding a product stream rich in ethylene, propylene, or combinations thereof from a fluidized catalytic cracking unit to a fractionator to separate the cracking product stream into three streams: a vapor product stream, a first crude naphtha product stream, and a liquid product stream; (ii) guiding the vapor product stream to an overhead condenser to produce a first cooling fluid stream having a temperature ranging from about 100°F to about 120°F; (iii) guiding the first cooling fluid stream to a cooler to produce a second cooling fluid stream having a temperature ranging from about 60°F to about 100°F; and (iv) supplying the second cooling fluid stream to a receiver to separate the second cooling fluid stream into a wet gas stream containing ethylene and propylene and a second crude naphtha stream. The wet gas stream is supplied to a wet gas compressor in a gas concentration unit to increase the pressure for downstream processing. In embodiments, the method further includes guiding spent catalyst from a riser of the fluidized catalytic cracking unit to a regenerator to produce entrained catalyst containing an inert material entraining the regenerated catalyst. The entrained catalyst is then passed through a stripping tower to remove inert material from the entrained catalyst, thereby producing a regenerated catalyst with a significant amount of entrained inert material removed. The method may also include introducing quench fluid into the riser of the fluidized catalytic cracking unit to reduce the contact time between the hydrocarbon feedstock and the catalyst in the riser by at least 0.5 seconds compared to an FCCU without this quench line.

[0043] When ranges are disclosed herein, a range beginning with any lower bound can be combined with any upper bound to enumerate ranges not explicitly enumerated, and a range beginning with any lower bound can be combined with any other lower bound to enumerate ranges not explicitly enumerated; similarly, a range beginning with any upper bound can be combined with any other upper bound to enumerate ranges not explicitly enumerated. Furthermore, although not explicitly stated, the values ​​described in the reference ranges include every value within that range. Therefore, each point or individual value can serve as its own lower or upper bound, or any other lower or upper bound, in combination with any other point or individual value, to enumerate ranges not explicitly enumerated.

[0044] Other objects, features, and advantages of this disclosure will become apparent from the foregoing drawings, detailed description, and examples. While these drawings, detailed description, and examples illustrate specific embodiments of this disclosure, they are given by way of illustration only and are not intended to be limiting. In other embodiments, features from specific embodiments may be combined with features from other embodiments. For example, a feature from one embodiment may be combined with features from any other embodiment. In other embodiments, additional features may be added to the specific embodiments described herein. It should be understood that although this disclosure contains certain aspects, embodiments, and optional features, modifications, improvements, or variations of such aspects, embodiments, and optional features can be made by those skilled in the art, and such modifications, improvements, or variations are considered to be within the scope of this disclosure.

Claims

1. An olefin production system, the system comprising: A fluidized bed catalytic cracking unit comprising a riser reactor and a regenerator, configured to receive hydrocarbon feedstock and produce a cracking product stream containing light and heavy alkanes, naphtha, aromatics and alkenes. A fractionator, which is in fluid communication with the fluidized catalytic cracking unit and configured to receive the cracking product stream and separate it into (i) a vapor product stream containing ethylene and propylene as well as light naphtha, (ii) a first crude naphtha product stream and (iii) a liquid product stream containing one or more of heavy naphtha, light circulating oil and slurry. A top condenser, which is in fluid communication with the fractionator, is configured to receive the vapor product stream and generate a first cooling fluid stream having a temperature ranging from about 105 degrees Fahrenheit (℉) to about 120℉. A cooler, which is in the gas concentration unit, is in fluid communication with the top condenser of the tower, and is configured to receive the first cooling fluid flow and generate a second cooling fluid flow having a temperature ranging from about 55℉ to about 100℉; The receiver is in the gas concentration unit, in fluid communication with the cooler, and configured to receive the second cooling fluid flow and separate the second cooling fluid flow into a wet gas flow containing ethylene and propylene and a second crude naphtha flow. as well as A wet gas compressor, which is in fluid communication with the receiver in the gas concentration unit, and configured to increase the pressure of the wet gas stream containing ethylene and propylene for supply to downstream processing to produce an olefin-rich product stream.

2. The olefin production system of claim 1, wherein the temperature of the first cooling fluid flow ranges from about 105℉ to about 115℉.

3. The olefin production system of claim 1, wherein the temperature of the second cooling fluid flow ranges from about 55℉ to about 75℉.

4. The olefin generation system of claim 1, wherein the riser reactor is configured to receive two or more hydrocarbon feed streams and a cracking catalyst.

5. The olefin production system of claim 1, wherein the wet gas compressor increases the pressure of the wet gas stream from 20 psig to 225 psig to supply it for the downstream processing.

6. The olefin generation system of claim 1, wherein the riser reactor includes a quench line for introducing quench fluid into the riser reactor 1.5 seconds after the hydrocarbon feedstock comes into contact with the catalyst.

7. The olefin generation system of claim 1, wherein when the temperature of the first cooling fluid flow decreases from about 105℉ to about 60℉, the volumetric flow rate of the wet gas flow decreases by about 35% of its volume.

8. An olefin production system, the system comprising: A fluidized catalytic cracking unit, the fluidized catalytic cracking unit comprising: A riser reactor configured to receive a hydrocarbon feedstock stream and a catalyst and produce a cracking product stream containing light and heavy alkanes, naphtha, aromatics and alkenes, as well as spent catalyst. A regenerator, connected to the riser reactor, and configured to receive the spent catalyst and regenerate it to produce an entrained catalyst containing an inert substance containing the regenerated catalyst. A stripping tower, which is connected to the regenerator and configured to receive the entrained catalyst and generate the regenerated catalyst by removing the inert substances contained in the entrained catalyst; as well as A conduit for supplying the regenerated catalyst to the riser reactor; A fractionator, which is in fluid communication with the fluidized catalytic cracking unit and configured to receive the cracking product stream and separate it into (i) a vapor product stream containing ethylene and propylene as well as light naphtha, (ii) a first crude naphtha product stream and (iii) a liquid product stream containing one or more of heavy naphtha, light circulating oil and slurry. as well as A vapor recovery unit, which is in fluid communication with the fractionator and configured to receive the vapor product stream and generate an olefin-rich product stream.

9. The olefin generation system of claim 8, wherein the regenerated catalyst is generated by removing about 75 percent of the inert material contained in the entrained catalyst.

10. The olefin generation system of claim 8, wherein the riser reactor is configured to receive two or more hydrocarbon feed streams and the catalyst.

11. The olefin generation system of claim 8, wherein the riser reactor includes a quench line for introducing quench fluid into the riser reactor 1.5 seconds after the hydrocarbon feed stream comes into contact with the catalyst.

12. An olefin production system, the system comprising: A fluidized catalytic cracking unit, the fluidized catalytic cracking unit comprising: A riser reactor configured to receive a hydrocarbon feedstock stream and a catalyst and produce a cracking product stream containing light and heavy alkanes, naphtha, aromatics and alkenes, as well as spent catalyst. A regenerator, connected to the riser reactor, and configured to receive the spent catalyst from the riser reactor and regenerate the spent catalyst to produce an entrained catalyst containing an inert substance containing the regenerated catalyst. A stripping tower, which is connected to the regenerator and configured to receive the entrained catalyst and generate the regenerated catalyst by removing the inert substances contained in the entrained catalyst; as well as A conduit for supplying the regenerated catalyst to the riser reactor; A fractionator, which is in fluid communication with the fluidized catalytic cracking unit and configured to receive the cracking product stream and separate it into (i) a vapor product stream containing ethylene and propylene as well as light naphtha, (ii) a first crude naphtha product stream and (iii) a liquid product stream containing one or more of heavy naphtha, light circulating oil and slurry. A top condenser, which is in fluid communication with the fractionator, is configured to receive the vapor product stream and generate a first cooling fluid stream having a temperature ranging from about 105 degrees Fahrenheit (℉) to about 120℉. A cooler, which is in fluid communication with the top condenser and is configured to receive a first cooling fluid flow from the top condenser and generate a second cooling fluid flow having a temperature ranging from about 55℉ to about 100℉; A receiver, which is in fluid communication with the cooler and configured to receive the second cooling fluid flow and separate the second cooling fluid flow into a wet gas flow containing ethylene and propylene and a second crude naphtha flow; as well as A wet gas compressor, which is in fluid communication with the receiver and configured to receive the wet gas stream and increase the pressure of the wet gas stream containing ethylene and propylene for supply to downstream processing to produce an olefin-rich product stream.

13. The olefin production system of claim 12, wherein the temperature of the first cooling fluid flow ranges from about 105℉ to about 115℉.

14. The olefin production system of claim 12, wherein the temperature of the second cooling fluid flow ranges from about 55℉ to about 75℉.

15. The olefin generation system of claim 12, wherein the riser reactor is configured to receive two or more hydrocarbon feed streams and the catalyst.

16. The olefin production system of claim 12, wherein the wet gas compressor increases the pressure of the wet gas stream from 20 psig to 225 psig to supply it for the downstream processing.

17. The olefin generation system of claim 12, wherein the regenerated catalyst is generated by removing about 75 percent of the inert material contained in the entrained catalyst.

18. The olefin generation system of claim 12, wherein the regenerated catalyst is generated by removing about 85 percent of the inert material contained in the entrained catalyst.

19. The olefin generation system of claim 12, wherein the riser reactor includes a quench line for introducing quench fluid into the riser reactor 1.5 seconds after the hydrocarbon feed stream comes into contact with the catalyst.

20. The olefin production system of claim 12, wherein when the temperature of the first cooling fluid flow decreases from about 105℉ to about 60℉ in the cooler, the volumetric flow rate of the wet gas flow decreases by about 35% of its volume.

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