An oxygen-enriched regeneration catalytic cracking process and system with by-product hydrogen

Abstract

The present invention discloses an oxygen-enriched regenerative catalytic cracking process and system with hydrogen as a byproduct. The oxygen-enriched regenerative catalytic cracking system includes a catalytic reactor, a catalyst regenerator, an oxygen-releasing reactor, a hydrogen production reactor, an oxygen absorption reactor, a normal-temperature water source, an air source, a fuel gas source, a first heat exchanger, a second heat exchanger, a third heat exchanger, a fourth heat exchanger, a fifth heat exchanger, a first condenser, and a second condenser. The present invention utilizes chemical chaining oxygen production technology to achieve oxygen-enriched regeneration of the catalyst, while simultaneously utilizing the heat released by the oxygen-enriched regeneration of the catalyst to produce hydrogen, thereby improving the charring capacity and processing capacity of the catalytic cracking unit, increasing product yield, and reducing pollutant emissions. This solves the problems of conventional air-regenerated catalytic cracking technology, such as low charring capacity, large regeneration flue gas volume, and complex subsequent processing processes.

Description

Technical Field

[0001] The present invention relates to the technical field of catalytic cracking, and in particular to an oxygen-enriched regeneration catalytic cracking process and system with by-product hydrogen. Background Art

[0002] Currently, refinery catalytic cracking units utilize conventional air regeneration technology, which suffers from drawbacks such as low coke burn capacity, large regeneration flue gas volumes, and complex subsequent treatment processes. To further enhance the processing capacity of catalytic cracking units, improve product yields, reduce pollutant emissions, and simplify subsequent regeneration flue gas treatment processes, oxygen-enriched regenerative catalytic cracking technology holds great promise. However, the high cost of conventional oxygen-generating technologies, such as cryogenic distillation, membrane separation, and pressure swing adsorption, has hindered the development of this technology.

[0003] Chemical looping air separation technology is a novel air separation technology. Its principle is to utilize an oxygen-rich oxygen carrier to release oxygen in an oxygen-releasing reactor to produce oxygen, while an oxygen-depleted oxygen carrier reacts with air in an oxygen-absorbing reactor for oxidation and regeneration. Compared to conventional oxygen production technologies, it offers advantages such as low energy consumption, fast startup, low cost, and convenient operation, paving the way for the development and application of oxygen-enriched regeneration technology for catalytic cracking. Under certain conditions, H2O reacts with a reduced oxygen carrier to produce H2. Simultaneously, using the same oxygen carrier to produce hydrogen further improves the economic efficiency of the oxygen-enriched regeneration process for catalytic cracking.

[0004] Reference 1: Chinese patent document with patent publication number CN113669752A.

[0005] Reference 1 combines chemical looping oxygen production with aerobic combustion to achieve oxygen-enriched combustion. This approach improves the reaction rate and thermal efficiency of aerobic combustion without significantly increasing oxygen production costs. However, this method, used in the catalyst regeneration process for catalytic cracking, suffers from slow reaction rates, low hydrogen production efficiency, and high system operating energy consumption. Summary of the Invention

[0006] The purpose of the present invention is to solve the problems of slow reaction speed, low hydrogen production efficiency and high system operation energy consumption in the existing catalytic cracking oxygen-enriched regeneration process, and to provide an oxygen-enriched regeneration catalytic cracking process and system with hydrogen as a by-product.

[0007] In order to solve the above technical problems, the present invention adopts the following technical solution: an oxygen-enriched regeneration catalytic cracking system with hydrogen as a by-product:

[0008] It includes a catalytic reactor, a catalyst regenerator, an oxygen release reactor, a hydrogen production reactor, an oxygen absorption reactor, a normal temperature water source, an air source, a fuel gas source, a first heat exchanger, a second heat exchanger, a third heat exchanger, a fourth heat exchanger, a fifth heat exchanger, a first condenser and a second condenser;

[0009] The discharge port of the oxygen absorption reactor is connected to the third cyclone separator, the gas phase discharge port of the third cyclone separator is connected to the second heat exchanger and the fourth heat exchanger in sequence, and the solid phase discharge port of the third cyclone separator is connected to the solid phase feed port of the oxygen release reactor;

[0010] The discharge port of the oxygen release reactor is connected to the first cyclone separator, the gas phase discharge port of the first cyclone separator is connected to the catalyst regenerator via the third heat exchanger, and the solid phase discharge port of the first cyclone separator is connected to the solid phase feed port of the hydrogen production reactor;

[0011] The discharge port of the hydrogen production reactor is connected to the second cyclone separator, the gas phase discharge port of the second cyclone separator is connected to the second condenser via the fifth heat exchanger, and the solid phase discharge port of the second cyclone separator is connected to the solid phase feed port of the oxygen absorption reactor;

[0012] The flue gas outlet of the catalyst regenerator is divided into two paths, one of which is connected to the gas phase feed port of the oxygen release reactor, and the other is connected to the first condenser after passing through the third heat exchanger and the first heat exchanger in sequence;

[0013] The normal temperature water source is divided into two paths after passing through the first heat exchanger and the second heat exchanger in sequence, one of which is connected to the gas phase feed port of the hydrogen production reactor, and the other is connected to the catalytic reactor;

[0014] The air source is connected to the gas phase feed port of the oxygen absorption reactor after passing through the fourth heat exchanger and the fifth heat exchanger in sequence;

[0015] The fuel gas source is connected to the gas phase feed port of the oxygen release reactor.

[0016] As a further optimization of the oxygen-enriched regenerative catalytic cracking system with by-product hydrogen of the present invention, the solid phase material circulating between the oxygen release reactor, the hydrogen production reactor and the oxygen absorption reactor is an oxygen carrier.

[0017] As a further optimization of the oxygen-enriched regeneration catalytic cracking system with by-product hydrogen of the present invention: the oxygen carrier is a metal oxygen carrier or a non-metallic oxygen carrier, the metal oxygen carrier is an iron-aluminum based oxygen carrier or an iron-cobalt based oxygen carrier, and the non-metallic oxygen carrier is a perovskite oxygen carrier.

[0018] As a further optimization of the oxygen-enriched regeneration catalytic cracking system with by-product hydrogen of the present invention: the oxygen carrier is an iron-cobalt based composite oxygen carrier, and the element mass ratio of Fe / Co in the composite oxygen carrier is 7:3.

[0019] As a further optimization of the oxygen-enriched regeneration catalytic cracking system with by-product hydrogen of the present invention: the catalytic reactor, catalyst regenerator, oxygen release reactor, hydrogen production reactor and oxygen absorption reactor are all fluidized bed reactors, and the operating pressure of the reactor is 0.1-0.5 MPa.

[0020] As a further optimization of the oxygen-enriched regeneration catalytic cracking system with by-product hydrogen of the present invention: the operating temperature of the oxygen release reactor is 600-750°C, the operating temperature of the hydrogen production reactor is 550-700°C, the operating temperature of the oxygen absorption reactor is 530-800°C, the operating temperature of the catalytic reactor is 500-650°C, and the operating temperature of the catalyst regenerator is 600-750°C.

[0021] An oxygen-enriched regenerative catalytic cracking process with hydrogen as a by-product comprises the following:

[0022] Normal temperature air enters the fourth heat exchanger to exchange heat with medium temperature oxygen-depleted air. After the temperature rises, it enters the fifth heat exchanger to exchange heat with high temperature hydrogen-rich gas. After the temperature rises, it enters the oxygen absorption reactor and reacts with the micro-oxygen carrier entering from the hydrogen production reactor to become high temperature oxygen-depleted air. It enters the second heat exchanger to exchange heat with medium temperature water vapor. After the temperature drops, it enters the fourth heat exchanger to exchange heat with normal temperature air for cooling. When the temperature drops below 40°C, it is directly discharged.

[0023] The micro-oxygen carrier absorbs oxygen in the oxygen absorption reactor and becomes an oxygen-rich oxygen carrier, then enters the oxygen release reactor, releases oxygen under the action of the regenerated flue gas and fuel gas, and becomes an oxygen-poor oxygen carrier and enters the hydrogen production reactor;

[0024] The oxygen-poor oxygen carrier enters the hydrogen production reactor and reacts with the high-temperature water vapor entering from the second heat exchanger to produce hydrogen. The oxygen-poor oxygen carrier becomes a low-oxygen oxygen carrier and enters the oxygen absorption reactor to complete the oxygen carrier cycle.

[0025] The hydrogen-rich gas produced by the hydrogen production reactor enters the fifth heat exchanger to exchange heat with air. After the temperature is reduced, it enters the second condenser for gas-liquid separation. The hydrogen-rich gas is separated into condensed water and hydrogen with a purity of more than 99%;

[0026] The oxygen-rich flue gas generated by the oxygen carrier releasing oxygen in the oxygen release reactor enters the third heat exchanger, exchanges heat with the catalyst regeneration flue gas, and after the temperature rises, enters the catalyst regenerator to complete the catalyst regeneration;

[0027] After the catalyst is regenerated by reacting with the oxygen-rich flue gas in the catalyst regenerator, it enters the catalyst reactor to participate in the reaction. Part of the regenerated flue gas generated by the regenerator enters the oxygen release reactor to provide heat for the oxygen release reactor and dilute the oxygen content to promote the oxygen release reaction. The other part enters the third heat exchanger to exchange heat with the oxygen-rich flue gas for cooling, and then enters the first heat exchanger to exchange heat with normal temperature water. After the temperature is lowered, it enters the first condenser for gas-liquid separation. The regenerated flue gas is separated into condensed water and CO2-rich gas with a purity of more than 95%. The CO2-rich gas is sealed and processed;

[0028] After entering the reactor, the regenerated catalyst reacts with the feedstock oil entering the reactor to produce an oil-gas mixture that enters the subsequent fractionation, absorption, and stabilization systems for treatment. The catalyst that has completed the reaction returns to the catalyst regenerator for oxygen-enriched regeneration treatment, completing the catalyst cycle.

[0029] Normal temperature water enters the first heat exchanger to exchange heat with high temperature flue gas, and the temperature rises to turn into water vapor and enter the second heat exchanger. After the temperature rises through heat exchange with high temperature oxygen-depleted air, part of it enters the hydrogen production reactor to participate in the hydrogen production reaction, and part enters the catalytic reactor to fluidize the catalyst and atomize the raw oil.

[0030] As a further optimization of the oxygen-enriched regeneration catalytic cracking process with by-product hydrogen of the present invention, the oxygen concentration of the oxygen-enriched flue gas entering the catalyst regenerator to regenerate the catalyst is adjusted to 21-50% by controlling the flue gas volume entering the oxygen release reactor and the oxygen carrier circulation volume.

[0031] As a further optimization of the oxygen-enriched regeneration catalytic cracking process with by-product hydrogen of the present invention, the oxygen concentration of the oxygen-enriched flue gas entering the catalyst regenerator to regenerate the catalyst is adjusted to 25-30% by controlling the flue gas volume entering the oxygen release reactor and the oxygen carrier circulation volume.

[0032] As a further optimization of the oxygen-enriched regeneration catalytic cracking process with by-product hydrogen of the present invention, the supplementary fuel gas entering the oxygen release reactor accounts for 1-5% of the volume of the mixed gas entering the oxygen release reactor.

[0033] The present invention has the following beneficial effects:

[0034] 1. In the oxygen-enriched regenerative catalytic cracking process of the present invention, the oxygen carrier circulates and reacts between the oxygen-releasing reactor, the hydrogen-producing reactor, and the oxygen-absorbing reactor, providing oxygen-enriched gas to the catalyst regenerator and producing hydrogen with a purity of more than 99% as a by-product. The additional energy consumed in the entire cycle comes entirely from the heat released by the combustion of the fuel gas.

[0035] 2. The oxygen-enriched regenerative catalytic cracking process of the present invention can improve the processing capacity of the catalytic cracking unit, change the product distribution, and improve the product yield. Oxygen-enriched regenerative catalytic cracking can significantly improve the regenerator's coking capacity, further reduce the catalyst's carbon content, improve the catalyst's reaction activity, and improve the processing capacity of the catalytic cracking unit; at the same time, it optimizes the product distribution and can increase the total liquid yield by 1 to 2%.

[0036] 3. The oxygen-enriched regeneration catalytic cracking process of the present invention can produce hydrogen with a purity of more than 99%, thereby improving the economic benefits of catalytic cracking technology. In conventional processes, the heat generated by catalyst regeneration is used for smoke exhaust fan operation and steam generation, and its economic value is relatively low.

[0037] 4. The oxygen-enriched regenerative catalytic cracking process of the present invention simplifies the subsequent treatment process of the regenerated flue gas and realizes the efficient capture of the regenerated flue gas. In the conventional process, the regenerated flue gas needs to pass through a complex denitrification and desulfurization system after cooling through the smoke exhaust fan and waste heat boiler, and the greenhouse gas CO2 in the flue gas is directly discharged into the atmosphere. The regenerated flue gas of the process of the present invention contains only CO2 and H2O and a very small amount of NO x and SO x After heat exchange and condensation, the flue gas is separated into CO2-rich gas with a concentration of more than 95%, which can be directly collected and processed. Without the complex processing steps of conventional processes, the regenerated flue gas is efficiently captured, effectively reducing pollutant emissions.

[0038] 5. In the oxygen-enriched regenerative catalytic cracking process of the present invention, part of the fuel gas is introduced into the oxygen release reactor. On the one hand, this consumes oxygen, reduces the oxygen partial pressure, and increases the oxygen release rate. On the other hand, the reaction releases heat, which can effectively ensure the reaction temperature of the reactor and promote the rapid progress of the oxygen release reaction. Compared with reference 1, the oxygen release rate is increased by 20 to 50% in the same time. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 Schematic diagram of the structure of the oxygen-enriched regeneration catalytic cracking system of the present invention;

[0040] Figure 2 Schematic diagram of the process of oxygen-enriched regeneration catalytic cracking process of the present invention;

[0041] Markings in the figure:

[0042] 1. Catalytic reactor;

[0043] 13. Regeneration inclined tube;

[0044] 2. Gas turbine;

[0045] 22. Return to the inclined pipe;

[0046] 3. Oxygen release reactor;

[0047] 33. First cyclone separator;

[0048] 4. Hydrogen production reactor;

[0049] 43. Second cyclone separator;

[0050] 5. Oxygen absorption reactor;

[0051] 53. Third cyclone separator;

[0052] 6. Normal temperature water source;

[0053] 7. Air source;

[0054] 8. Fuel gas source;

[0055] E1, first heat exchanger;

[0056] E2, second heat exchanger;

[0057] E3, the third heat exchanger;

[0058] E4, fourth heat exchanger;

[0059] E5, fifth heat exchanger;

[0060] R1, first condenser;

[0061] R2, second condenser. DETAILED DESCRIPTION

[0062] In order to better understand the present invention, the content of the present invention is further illustrated below in conjunction with examples, but the content of the present invention is not limited to the following examples.

[0063] <Oxygen-enriched regeneration catalytic cracking system with by-product hydrogen>

[0064] like Figure 1 As shown: An oxygen-enriched regeneration catalytic cracking system with by-product hydrogen includes a catalytic reactor 1, a catalyst regenerator 2, an oxygen release reactor 3, a hydrogen production reactor 4, an oxygen absorption reactor 5, a normal temperature water source 6, an air source 7, a fuel gas source 8, a first heat exchanger E1, a second heat exchanger E2, a third heat exchanger E3, a fourth heat exchanger E4, a fifth heat exchanger E5, a first condenser R1 and a second condenser R2.

[0065] The oxygen-releasing reactor 3, hydrogen-producing reactor 4, and oxygen-absorbing reactor 5 all have solid-phase feed ports located on the lower sidewalls of the reactors. They also have gas-phase feed ports located at the bottoms of the reactors. They also have discharge ports located on the upper sidewalls of the reactors.

[0066] The discharge port of the oxygen absorption reactor 5 is connected to the third cyclone separator 53, the gas phase discharge port of the third cyclone separator 53 is connected to the second heat exchanger E2 and the fourth heat exchanger E4 in sequence, and the solid phase discharge port of the third cyclone separator 53 is connected to the solid phase feed port of the oxygen release reactor 3.

[0067] The discharge port of the oxygen release reactor 3 is connected to the first cyclone separator 33 , the gas phase discharge port of the first cyclone separator 33 is connected to the catalyst regenerator 2 via the third heat exchanger E3 , and the solid phase discharge port of the first cyclone separator 33 is connected to the solid phase feed port of the hydrogen production reactor 4 .

[0068] The oxygen-rich oxygen carrier enters the oxygen-releasing reactor 3 through the third cyclone separator 53. Fluidized by the 600-750°C catalyst regeneration flue gas, it releases oxygen, transforming into an oxygen-depleted oxygen carrier (FeO+COO) at 550-700°C and an oxygen-rich gas. The oxygen carrier rises with the oxygen-rich gas to the first cyclone separator 33 for gas-solid separation. The oxygen-depleted oxygen carrier enters the hydrogen production reactor 4 through the first cyclone separator 33.

[0069] The discharge port of the hydrogen production reactor 4 is connected to the second cyclone separator 43 , the gas phase discharge port of the second cyclone separator 43 is connected to the second condenser R2 via the fifth heat exchanger E5 , and the solid phase discharge port of the second cyclone separator 43 is connected to the solid phase feed port of the oxygen absorption reactor 5 .

[0070] The oxygen-depleted oxygen carrier enters hydrogen production reactor 4 and, under the fluidization of 600-750°C high-temperature steam entering from second heat exchanger E2, reacts with it as it rises, producing hydrogen. The oxygen-depleted oxygen carrier becomes a low-oxygen oxygen carrier at 500-650°C, rising with the hydrogen-rich gas to second cyclone separator 43. The low-oxygen oxygen carrier passes through the feed leg of second cyclone separator 43 and enters oxygen absorption reactor 5, completing the oxygen carrier cycle.

[0071] The 500-650°C hydrogen-rich gas produced by the hydrogen production reactor 4 is separated by the second cyclone separator 43 and then enters the fifth heat exchanger E5 for heat exchange with air. The temperature is reduced to below 150°C and then enters the second condenser R2 for gas-liquid separation. The hydrogen-rich gas is separated into condensed water and hydrogen with a purity of more than 99%.

[0072] The 500-650°C micro-oxygen carrier (Fe3O4 + CO3O4) from the oxygen carrier in the fluidized second cyclone separator 43 enters the oxygen absorption reactor and reacts with it to become a gas-solid mixture of 650-800°C oxygen-depleted air and oxygen-rich carrier (Fe2O3 + CO2O3). The mixture then enters the third cyclone separator 53 for gas-solid separation. The 650-800°C oxygen-depleted air enters the second heat exchanger E2 for heat exchange with medium-temperature water vapor, where its temperature drops to 250-300°C. The air then enters the fourth heat exchanger E4 for heat exchange with room-temperature air, where it is cooled to below 40°C and is directly discharged.

[0073] The flue gas outlet of the catalyst regenerator 2 is divided into two routes, one of which is connected to the gas phase feed port of the oxygen release reactor 3, and the other is connected to the first condenser R1 after passing through the third heat exchanger E3 and the first heat exchanger E1 in sequence.

[0074] The 550-700℃ oxygen-rich flue gas generated by the oxygen carrier in the oxygen release reactor 3 is separated by the first cyclone separator 33 and then enters the third heat exchanger E3, where it exchanges heat with the 600-750℃ catalyst regeneration flue gas. The temperature rises to 570-720℃ and enters the catalyst regenerator 2 to complete catalyst regeneration.

[0075] In regenerator 2, the catalyst rises and reacts under the fluidization of oxygen-enriched flue gas at 570-720°C. After regeneration, it enters the cyclone separator at the top of regenerator 2 for gas-solid separation. The regenerated catalyst then returns to catalyst reactor 1 through return inclined pipe 22 to participate in the reaction. After gas-solid separation in the cyclone separator, the regenerated flue gas at 600-750°C is drawn from the top of the regenerator. A portion is mixed with ambient temperature fuel gas and enters oxygen release reactor 3, fluidizing the oxygen carrier and providing heat for the oxygen release reactor. The remaining portion enters the third heat exchanger E3, exchanges heat with the oxygen-enriched flue gas to a temperature of 570-730°C. It then enters the first heat exchanger E1 for heat exchange with ambient temperature water, cooling the temperature to below 150°C. It then enters the first condenser R1 for gas-liquid separation. The regenerated flue gas is separated into condensed water and CO2-rich gas with a purity exceeding 95%. The CO2-rich gas is then sealed and processed.

[0076] After entering reactor 1, the regenerated catalyst reacts with the feedstock oil entering reactor 1 through the feedstock oil inlet. Fluidized by the steam entering the reactor, the catalyst rises and reacts, then enters the cyclone separator at the top of the reactor for gas-solid separation. The resulting oil-gas mixture then enters the subsequent fractionation, absorption, and stabilization systems from the top of the reactor for processing. The reacted catalyst is separated in the cyclone separator and returned to the regenerator through the regeneration inclined pipe 13 for oxygen-enriched regeneration, completing the catalyst cycle.

[0077] The normal temperature water source 6 passes through the first heat exchanger E1 and the second heat exchanger E2 in sequence and is divided into two paths, one of which is connected to the gas phase feed port of the hydrogen production reactor 4, and the other is connected to the catalytic reactor 1.

[0078] Normal temperature water enters the first heat exchanger E1 and exchanges heat with the 570-730℃ high temperature flue gas. The temperature rises to 200-250℃ water vapor and enters the second heat exchanger E2. It exchanges heat with the 650-800℃ high temperature oxygen-depleted air and the temperature rises to 600-750℃. Part of it enters the hydrogen production reactor 3 to participate in the hydrogen production reaction, and part enters the catalytic reactor 1 to fluidize the catalyst and atomize the raw oil.

[0079] The air source 7 is connected to the gas phase feed port of the oxygen absorption reactor 5 after passing through the fourth heat exchanger E4 and the fifth heat exchanger E5 in sequence.

[0080] Normal temperature air enters the fourth heat exchanger E4 and exchanges heat with the medium temperature oxygen-depleted air of 250-300°C. After the temperature rises, it enters the fifth heat exchanger E5 and exchanges heat with the high temperature hydrogen-rich gas of 500-650°C. After the temperature rises to 450-600°C, it enters the oxygen absorption reactor 5.

[0081] The fuel gas source 8 is connected to the gas phase feed port of the oxygen release reactor 3 .

[0082] The solid phase material circulating between the oxygen release reactor 3, the hydrogen production reactor 4, and the oxygen absorption reactor 5 is an oxygen carrier. The oxygen carrier is a metal oxygen carrier or a non-metallic oxygen carrier. The metal oxygen carrier is an iron-aluminum-based oxygen carrier or an iron-cobalt-based oxygen carrier, and the non-metallic oxygen carrier is a perovskite oxygen carrier.

[0083] Among the commonly used oxygen carriers, Co oxygen carrier has high activity, high reaction speed and conversion degree, but is relatively expensive; Fe oxygen carrier has a lower reaction speed but better stability; Al-based oxygen carrier has a moderate price and a moderate reaction rate. Cu-based oxygen carrier has a low melting point and has problems with long-term operation; Mn-based oxygen carrier pollutes the environment. Therefore, Fe-Co-based oxygen carriers are the most suitable in terms of stability, reaction speed and economy; Fe-Al-based oxygen carriers have a lower reaction speed than Fe-Co-based oxygen carriers, but can also complete the system reaction well, while non-metallic oxygen carriers have problems with long-term operation.

[0084] In this embodiment, the oxygen carrier is an iron-cobalt-based composite oxygen carrier, and the element mass ratio of Fe / Co in the composite oxygen carrier is 7:3. Compared with conventional oxygen carriers, this specific composite oxygen carrier has better comprehensive performance in conversion rate, cycle stability and economy, and can improve the system operation efficiency.

[0085] The catalytic reactor 1, the catalyst regenerator 2, the oxygen release reactor 3, the hydrogen production reactor 4 and the oxygen absorption reactor 5 are all fluidized bed reactors, and the operating pressure of the reactor is 0.1-0.5 MPa.

[0086] The operating temperature of the oxygen release reactor 3 is 600-750°C, the operating temperature of the hydrogen production reactor 4 is 550-700°C, the operating temperature of the oxygen absorption reactor 5 is 530-800°C, the operating temperature of the catalytic reactor 1 is 500-650°C, and the operating temperature of the catalyst regenerator 2 is 600-750°C.

[0087] In this system, water vapor and oxygen-depleted air are heat-exchanged and enter the hydrogen production reactor. The water vapor temperature is 500-750°C, and the oxygen-depleted air temperature discharged from the first heat exchanger is lower than 40°C.

[0088] Since the oxygen release reaction and the hydrogen production reaction are endothermic reactions, the reaction temperature needs to be guaranteed to ensure the reaction rate and system operation efficiency. The temperature of the oxygen release reactor and the hydrogen production reactor plays an extremely critical role in the system operation efficiency. At the same time, since the oxygen absorption reaction is an exothermic reaction, the temperature of the air entering the oxygen absorption reactor is slightly reduced, which has little effect on the system reaction speed and operation efficiency. Therefore, the present invention adopts the method of introducing fuel gas into the oxygen release reactor and increasing the temperature of water vapor entering the hydrogen production reactor to ensure the temperature of the oxygen release reactor and the temperature of the hydrogen production reactor, thereby improving the operation efficiency of the entire system. In reference 1, in order to realize the hydrogenation reaction of carbon dioxide, the temperatures of the oxygen release reaction and the hydrogen production reaction are relatively low, the reaction speed is relatively slow, and the system operation efficiency is low.

[0089] Compared with Reference 1 and the prior art, the present invention has at least the following technical advantages:

[0090] (1) The specific implementation of the oxygen-enriched regeneration catalytic cracking process and system for by-product hydrogen focuses on effectively achieving technical effects through special processes and equipment based on the characteristics of the catalytic cracking process.

[0091] (2) In view of the inapplicability and shortcomings of the comparative documents in the catalytic cracking process, the process route is optimized and improved, and system equipment is constructed to enable it to be implemented efficiently and quickly in the catalytic cracking process.

[0092] (3) Improve the operating efficiency of the entire system and reduce energy consumption.

[0093] <Oxygen-enriched regeneration catalytic cracking process with by-product hydrogen>

[0094] like Figure 2 Shown: An oxygen-enriched regeneration catalytic cracking process with hydrogen as a by-product:

[0095] 1) Normal temperature air enters the fourth heat exchanger E4 and exchanges heat with medium temperature oxygen-depleted air at 250-300°C. After the temperature is increased, it enters the fifth heat exchanger E5 and exchanges heat with high temperature hydrogen-rich gas at 500-650°C. After the temperature is increased to 450-600°C, it enters the oxygen absorption reactor 5 and reacts with the 500-650°C micro-oxygen carrier entering from the hydrogen production reactor 4 to become high temperature oxygen-depleted air at 650-800°C. It enters the second heat exchanger E2 and exchanges heat with medium temperature water vapor. After the temperature is reduced to 250-300°C, it enters the fourth heat exchanger E4 and exchanges heat with normal temperature air to cool down. When the temperature drops below 40°C, it is directly discharged.

[0096] 2) The micro-oxygen carrier absorbs oxygen in the oxygen absorption reactor 5 and becomes an oxygen-rich oxygen carrier at 650-800°C, and then enters the oxygen release reactor 3. Under the action of the regenerated flue gas at 600-750°C and the normal temperature fuel gas, it releases oxygen and becomes an oxygen-depleted oxygen carrier at 550-700°C and enters the hydrogen production reactor 4.

[0097] 3) The oxygen-poor oxygen carrier enters the hydrogen production reactor 4 and reacts with the 600-750°C high-temperature steam entering from the second heat exchanger E2 to produce hydrogen. The oxygen-poor oxygen carrier becomes a 500-650°C low-oxygen oxygen carrier and enters the oxygen absorption reactor 5 to complete the oxygen carrier cycle.

[0098] 4) The 500-650°C hydrogen-rich gas produced by the hydrogen production reactor 4 enters the fifth heat exchanger for heat exchange with the 50-100°C air. The temperature is reduced to below 150°C and enters the second condenser R2 for gas-liquid separation. The hydrogen-rich gas is separated into condensed water and hydrogen with a purity of more than 99%.

[0099] 5) The oxygen-enriched flue gas at 550-700°C produced by the oxygen carrier in the oxygen release reactor 3 enters the third heat exchanger E3, exchanges heat with the catalyst regeneration flue gas at 600-750°C, and the temperature rises to 570-720°C before entering the catalyst regenerator 2 to complete catalyst regeneration.

[0100] 6) After regeneration in regenerator 2 by reacting with oxygen-enriched flue gas at 570-720°C, the catalyst enters catalyst reactor 1 to participate in the reaction. A portion of the regenerated flue gas, at 600-750°C, produced in the regenerator enters oxygen release reactor 3, providing heat to the reactor and diluting the oxygen content to promote the oxygen release reaction. The remaining portion enters the third heat exchanger E3, where it exchanges heat with the oxygen-enriched flue gas to a temperature of 570-730°C. It then enters the first heat exchanger E1, where it exchanges heat with ambient temperature water, dropping its temperature below 150°C. It then enters the first condenser R1 for gas-liquid separation. The regenerated flue gas is separated into condensed water and CO2-rich gas with a purity exceeding 95%. The CO2-rich gas is then sealed and processed.

[0101] 7) After entering reactor 1, the regenerated catalyst reacts with the feedstock oil, producing an oil-gas mixture that enters the subsequent fractionation, absorption, and stabilization systems for processing. The completed catalyst returns to the regenerator for oxygen-enriched regeneration, completing the catalyst cycle.

[0102] 8) Normal temperature water enters the first heat exchanger E1 to exchange heat with the 570-730°C high temperature flue gas, and the temperature is increased to 200-250°C water vapor, which enters the second heat exchanger E2 to exchange heat with the 650-800°C high temperature oxygen-depleted air, raising the temperature to 600-750°C. Part of the water enters the hydrogen production reactor 4 to participate in the hydrogen production reaction, and part enters the catalytic reactor 1 to fluidize the catalyst and atomize the feedstock oil.

[0103] The above describes the specific embodiments of the present invention. It should be understood that the present invention is not limited to the above specific embodiments, and those skilled in the art may make various variations or modifications within the scope of the claims, which do not affect the essence of the present invention.

Claims

1. An oxygen-enriched regenerative catalytic cracking system with hydrogen as a by-product, characterized by: The invention comprises a catalytic reactor (1), a catalyst regenerator (2), an oxygen release reactor (3), a hydrogen production reactor (4), an oxygen absorption reactor (5), a normal temperature water source (6), an air source (7), a fuel gas source (8), a first heat exchanger (E1), a second heat exchanger (E2), a third heat exchanger (E3), a fourth heat exchanger (E4), a fifth heat exchanger (E5), a first condenser (R1) and a second condenser (R2); The discharge port of the oxygen absorption reactor (5) is connected to the third cyclone separator (53), the gas phase discharge port of the third cyclone separator (53) is connected to the second heat exchanger (E2) and the fourth heat exchanger (E4) in sequence, and the solid phase discharge port of the third cyclone separator (53) is connected to the solid phase feed port of the oxygen release reactor (3); The discharge port of the oxygen release reactor (3) is connected to the first cyclone separator (33), the gas phase discharge port of the first cyclone separator (33) is connected to the catalyst regenerator (2) via the third heat exchanger (E3), and the solid phase discharge port of the first cyclone separator (33) is connected to the solid phase feed port of the hydrogen production reactor (4); The discharge port of the hydrogen production reactor (4) is connected to the second cyclone separator (43), the gas phase discharge port of the second cyclone separator (43) is connected to the second condenser (R2) via the fifth heat exchanger (E5), and the solid phase discharge port of the second cyclone separator (43) is connected to the solid phase feed port of the oxygen absorption reactor (5); The flue gas outlet of the catalyst regenerator (2) is divided into two routes, one of which is connected to the gas phase feed port of the oxygen release reactor (3), and the other is connected to the first condenser (R1) after passing through the third heat exchanger (E3) and the first heat exchanger (E1) in sequence; The normal temperature water source (6) passes through the first heat exchanger (E1) and the second heat exchanger (E2) in sequence and is divided into two paths, one of which is connected to the gas phase feed port of the hydrogen production reactor (4), and the other is connected to the catalytic reactor (1); The air source (7) is connected to the gas phase feed port of the oxygen absorption reactor (5) after passing through the fourth heat exchanger (E4) and the fifth heat exchanger (E5) in sequence; The fuel gas source (8) is connected to the gas phase feed port of the oxygen release reactor (3).

2. The oxygen-enriched regeneration catalytic cracking system with hydrogen by-product as claimed in claim 1, characterized in that: The solid phase material circulating between the oxygen release reactor (3), the hydrogen production reactor (4) and the oxygen absorption reactor (5) is an oxygen carrier.

3. The oxygen-enriched regeneration catalytic cracking system with hydrogen by-product as claimed in claim 2, characterized in that: The oxygen carrier is a metal oxygen carrier or a non-metal oxygen carrier. The metal oxygen carrier is an iron-aluminum-based oxygen carrier or an iron-cobalt-based oxygen carrier, and the non-metal oxygen carrier is a perovskite oxygen carrier.

4. The oxygen-enriched regenerative catalytic cracking system with hydrogen by-product as claimed in claim 3, characterized in that: The oxygen carrier is an iron-cobalt based composite oxygen carrier, and the element mass ratio of Fe / Co in the composite oxygen carrier is 7:

3.

5. The oxygen-enriched regeneration catalytic cracking system with hydrogen by-product as claimed in claim 1, characterized in that: The catalytic reactor (1), catalyst regenerator (2), oxygen release reactor (3), hydrogen production reactor (4) and oxygen absorption reactor (5) are all fluidized bed reactors, and the operating pressure of the reactor is 0.1-0.5 MPa.

6. The oxygen-enriched regeneration catalytic cracking system with hydrogen by-product as claimed in claim 5, characterized in that: The operating temperature of the oxygen release reactor (3) is 600-750°C, the operating temperature of the hydrogen production reactor (4) is 550-700°C, the operating temperature of the oxygen absorption reactor (5) is 530-800°C, the operating temperature of the catalytic reactor (1) is 500-650°C, and the operating temperature of the catalyst regenerator (2) is 600-750°C.

7. An oxygen-enriched regenerative catalytic cracking process with hydrogen as a by-product, characterized by: Normal temperature air enters the fourth heat exchanger (E4) and exchanges heat with medium temperature oxygen-deficient air. After the temperature is increased, it enters the fifth heat exchanger (E5) and exchanges heat with high temperature hydrogen-rich gas. After the temperature is increased, it enters the oxygen absorption reactor (5) and reacts with the micro-oxygen carrier entering from the hydrogen production reactor (4) to become high temperature oxygen-deficient air. It enters the second heat exchanger (E2) and exchanges heat with medium temperature water vapor. After the temperature is reduced, it enters the fourth heat exchanger (E4) and exchanges heat with normal temperature air to cool down. When the temperature drops below 40°C, it is directly discharged. The micro-oxygen carrier absorbs oxygen in the oxygen absorption reactor (5) and becomes an oxygen-rich oxygen carrier, which then enters the oxygen release reactor (3). Under the action of the regenerated flue gas and fuel gas, the carrier releases oxygen and becomes an oxygen-poor oxygen carrier, which enters the hydrogen production reactor (4). The oxygen-poor oxygen carrier enters the hydrogen production reactor (4) and reacts with the high-temperature water vapor entering from the second heat exchanger (E2) to produce hydrogen. The oxygen-poor oxygen carrier becomes a low-oxygen oxygen carrier and enters the oxygen absorption reactor (5) to complete the circulation of the oxygen carrier. The hydrogen-rich gas produced by the hydrogen production reactor (4) enters the fifth heat exchanger (E5) to exchange heat with air, and after the temperature is reduced, enters the second condenser (R2) for gas-liquid separation. The hydrogen-rich gas is separated into condensed water and hydrogen with a purity of more than 99%; The oxygen-rich flue gas generated by the oxygen carrier releasing oxygen in the oxygen release reactor (3) enters the third heat exchanger (E3), exchanges heat with the catalyst regeneration flue gas, and after the temperature is increased, enters the catalyst regenerator (2) to complete the catalyst regeneration; After the catalyst is regenerated by reacting with the oxygen-rich flue gas in the catalyst regenerator (2), it enters the catalytic reactor (1) to participate in the reaction. A portion of the regenerated flue gas generated by the catalyst regenerator (2) enters the oxygen release reactor (3) to provide heat for the oxygen release reactor (3) and dilute the oxygen content to promote the oxygen release reaction. The other portion enters the third heat exchanger (E3) to exchange heat with the oxygen-rich flue gas for cooling, and then enters the first heat exchanger (E1) to exchange heat with normal temperature water. After the temperature is lowered, it enters the first condenser (R1) for gas-liquid separation. The regenerated flue gas is separated into condensed water and CO2-rich gas with a purity of more than 95%, and the CO2-rich gas is sealed and processed. After entering the catalytic reactor (1), the regenerated catalyst reacts with the feedstock oil entering the catalytic reactor (1) to produce an oil-gas mixture which enters a subsequent fractionation and absorption-stabilization system for treatment. The catalyst that has completed the reaction returns to the catalyst regenerator (2) for oxygen-enriched regeneration treatment, thus completing the catalyst cycle. Normal temperature water enters the first heat exchanger (E1) to exchange heat with high temperature flue gas, and the temperature rises to become water vapor, which enters the second heat exchanger (E2). After the temperature rises through heat exchange with high temperature oxygen-depleted air, part of it enters the hydrogen production reactor (4) to participate in the hydrogen production reaction, and part of it enters the catalytic reactor (1) to fluidize the catalyst and atomize the raw oil.

8. The oxygen-enriched regeneration catalytic cracking process with by-product hydrogen as claimed in claim 7, characterized in that: By controlling the flue gas volume entering the oxygen release reactor (3) and the oxygen carrier circulation volume, the oxygen concentration of the oxygen-enriched flue gas entering the catalyst regenerator (2) to regenerate the catalyst is adjusted to 21-50%.

9. The oxygen-enriched regeneration catalytic cracking process with by-product hydrogen as claimed in claim 8, characterized in that: By controlling the flue gas volume entering the oxygen release reactor (3) and the oxygen carrier circulation volume, the oxygen concentration of the oxygen-enriched flue gas entering the catalyst regenerator (2) to regenerate the catalyst is adjusted to 25-30%.

10. The oxygen-enriched regeneration catalytic cracking process with by-product hydrogen as claimed in claim 7, characterized in that: The supplementary fuel gas entering the oxygen release reactor accounts for 1-5% of the volume of the mixed gas entering the oxygen release reactor.

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