A process for the regeneration of spent catalytic cracking catalyst and the production of co

Abstract

The present application relates to a method for regenerating spent catalytic cracking catalyst and producing CO, which comprises: (1) contacting a hydrocarbon oil feedstock with a catalytic cracking catalyst in a catalytic cracking reactor and performing catalytic cracking reaction, separating reaction oil gas and coked spent catalyst; (2) sequentially performing first regeneration and second regeneration on the spent catalyst after stripping, obtaining regenerated catalyst and flue gas; the first regeneration zone is a bubbling bed, and the second regeneration zone is a fast bed; CO2 is introduced into the lower part of the first regeneration zone, and oxygen-containing gas with the volume ratio of oxygen greater than or equal to 22% is introduced into the lower part of the second regeneration zone; the regeneration temperature of the first regeneration is 700-800 DEG C; (3) recycling at least part of the regenerated catalyst to the catalytic cracking reactor, and introducing the flue gas from the top of the regenerator and then separating to obtain the CO product.

Description

Technical Field

[0001] This invention relates to the field of catalytic cracking technology for petroleum hydrocarbons, and more specifically to a method for producing CO based on the regeneration of spent catalyst from catalytic cracking. Background Technology

[0002] Catalytic cracking of petroleum feedstocks is a crucial petroleum refining process. A catalytic cracking unit primarily consists of a catalytic cracking reactor and a catalyst regenerator. In the catalyst regenerator, regeneration gas is used to regenerate the coked catalyst, simultaneously generating regeneration flue gas. During catalyst regeneration, coke combustion produces a large amount of CO2 gas, making the catalytic cracking unit the largest source of CO2 emissions in refineries, accounting for 15% to 50% of total refinery emissions. Each ton of feedstock processed by a catalytic cracking unit emits 211.7 kg of CO2. China has approximately 190 catalytic cracking units with a total processing capacity of about 210 million tons per year, resulting in at least 40 million tons of CO2 emissions.

[0003] During catalyst regeneration, the large amount of heat generated leads to excess heat in the catalytic converter. External heat recovery devices are needed to convert this heat into steam energy and recover energy from the high-temperature flue gas, but these methods represent low-quality energy utilization. Furthermore, the regenerated flue gas contains carbon monoxide, which often causes tail combustion, leading to localized overheating of the regenerator and accelerated catalyst deactivation. Controlling the oxygen content in the flue gas can reduce tail combustion, but this reduces the coking rate and intensity, while also introducing exhaust emissions and resulting in the loss of chemical energy from the carbon monoxide. Refineries often use carbon monoxide combustion aids or flue gas boilers to reduce carbon monoxide in the flue gas and recover energy, but the problem of carbon monoxide in the flue gas remains unresolved.

[0004] CN1400159A discloses a method for producing hydrogen using catalytic cracking regenerated flue gas. This method allows for the rational utilization of CO in the regenerated flue gas and alleviates the problem of excess heat in FCC units. However, the CO content obtained by this method is low, around 14 vol%, while the nitrogen content is above 70 vol%.

[0005] CN102698817A discloses a pure oxygen regeneration process and hydrogen production method for fluidized catalytic cracking catalysts, which can significantly improve energy utilization quality and efficiency, reduce energy consumption and pollutant emissions of FCC regeneration systems, and simultaneously produce hydrogen from the generated CO through a water-gas shift reaction.

[0006] CN101457152A discloses a hydrocarbon-oil conversion method in which, during the regeneration process, the spent catalyst is contacted with water vapor and oxygen-containing gas in a gasifier to obtain syngas and a semi-regenerated catalyst. This method can increase the yield of carbon monoxide and hydrogen, and carbon monoxide can also be converted into hydrogen in subsequent processing, thereby achieving a high hydrogen yield.

[0007] However, existing technologies for producing hydrogen through incompletely regenerated flue gas, while utilizing coke, still primarily emit carbon as carbon dioxide; and the method of directly contacting the spent catalyst with water vapor to produce syngas accelerates catalyst deactivation.

[0008] How to convert the carbon deposits on the spent catalyst produced by catalytic cracking into flue gas with higher CO selectivity during catalyst regeneration, thereby reducing carbon emissions from the catalytic cracking unit and simultaneously producing CO, is a pressing technical problem that needs to be solved. Summary of the Invention

[0009] This invention provides a method for regenerating and producing CO based on catalytic cracking spent catalyst, with the aim of enabling the spent catalyst with carbon deposits to be converted into flue gas with higher CO selectivity during the regeneration process.

[0010] This invention relates to a method for regenerating spent catalyst from catalytic cracking and producing CO, comprising the following steps:

[0011] (1) The hydrocarbon feedstock and the catalytic cracking catalyst are brought into contact in the catalytic cracking reactor and the catalytic cracking reaction is carried out to separate the reaction oil and gas and the ungenerated catalyst with carbon deposits.

[0012] (2) The regenerator is provided with a first regeneration zone and a second regeneration zone connected from top to bottom, so that the catalyst to be generated passes through the first regeneration zone and the second regeneration zone in sequence after stripping to perform first regeneration and second regeneration respectively, to obtain regenerated catalyst and flue gas.

[0013] The first regeneration zone is a bubble bed, and the second regeneration zone is a rapid regeneration bed;

[0014] CO2 is introduced into the lower part of the first regeneration zone, so that the catalyst to be regenerated entering the first regeneration zone comes into contact with CO2 and the second flue gas from the second regeneration zone to perform the first regeneration;

[0015] Oxygen-containing gas is introduced into the lower part of the second regeneration zone to contact the semi-regenerated agent that has undergone the first regeneration and perform the second regeneration.

[0016] The regeneration gas includes CO2 introduced into the lower part of the first regeneration zone and the oxygen-containing gas introduced into the lower part of the second regeneration zone;

[0017] The oxygen-containing gas introduced into the lower part of the second regeneration zone has an oxygen volume ratio greater than or equal to 22%; the regeneration temperature of the first regeneration is 700-800℃;

[0018] (3) At least a portion of the regenerated catalyst is returned to the catalytic cracking reactor for recycling, and the flue gas is drawn out from the top of the regenerator and then separated to obtain CO product.

[0019] Optionally, the density of the bubble bed is 300–700 kg / m³. 3 ; and / or,

[0020] The bed density of the rapid bed is 120-300 kg / m³. 3 .

[0021] Optionally, the conditions for the first regeneration include: an apparent gas linear velocity of 0.1 to 1 m / s and an average catalyst residence time of 0.6 to 20 minutes.

[0022] Optionally, the volume percentage of CO2 introduced into the lower part of the first regeneration zone in the regeneration gas is 1-50%, preferably 2-15%.

[0023] Optionally, the conditions for the second regeneration include: a regeneration temperature of 600–700°C, a gas apparent linear velocity of 0.8–4 m / s, and an average catalyst residence time of 0.6–15 minutes.

[0024] Optionally, the oxygen-containing gas introduced into the lower part of the second regeneration zone is a mixture of CO2 and O2.

[0025] The total amount of CO2 introduced into the lower part of the first regeneration zone and the total amount of CO2 introduced into the lower part of the second regeneration zone accounts for 1-89% of the volume of the regeneration gas, preferably 60-80%.

[0026] Optionally, the volume ratio of the second regeneration zone to the first regeneration zone is 1:(1-10).

[0027] Optionally, in step (1), the hydrocarbon feedstock includes petroleum hydrocarbons and / or other mineral oils, wherein the petroleum hydrocarbons are selected from one or more of gasoline, diesel, vacuum wax oil, atmospheric wax oil, coking wax oil, deasphalted oil, vacuum residue, atmospheric residue, extracted oil and inferior recycled oil, and the other mineral oils are selected from one or more of coal liquefaction oil, oil sands oil and shale oil.

[0028] Optionally, in step (1), the conditions for the catalytic cracking reaction include: a reaction temperature of 450 to 700°C, a time of 1 to 10 seconds, and an agent-to-oil ratio of (1 to 100):1.

[0029] Optionally, the catalytic cracking reactor is a riser reactor, a fluidized bed reactor, or a combination of both.

[0030] Beneficial effects:

[0031] (1) The present invention controls the combustion of coke in the catalyst regeneration process, so that it undergoes incomplete combustion to generate CO, and stores some of the energy as chemical energy in CO. This can reduce the excess heat in the catalyst regeneration process, solve the problem of tail combustion of the regenerator, and at the same time significantly reduce CO2 emissions without affecting the catalyst regeneration effect.

[0032] (2) Enhance the reaction between CO2 and coke to further increase CO production.

[0033] (3) The regeneration process does not introduce N2, which is beneficial to the separation of CO and CO2 and reduces the energy consumption of separation.

[0034] (4) The generated CO can be used as raw material for subsequent chemical and metallurgical processes, saving raw materials such as coal and methane used in CO production, saving resources and energy consumption, and further reducing emissions.

[0035] (5) Producing CO using the catalytic cracking regeneration process can turn waste into treasure and save energy and reduce emissions, which has huge economic and social benefits. Attached Figure Description

[0036] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used together with the following detailed description to explain the invention, but do not constitute a limitation thereof. In the drawings:

[0037] Figure 1 This is a schematic diagram of a specific embodiment of the method for regenerating and producing CO based on catalytic cracking spent catalyst of the present invention, or a system for regenerating and producing CO based on catalytic cracking spent catalyst.

[0038] Figure 2 This is a schematic diagram of the catalytic cracking process of the single-stage regeneration method in Comparative Examples 3 and 5 of the present invention;

[0039] Explanation of reference numerals in the attached figures:

[0040] 1. Hydrocarbon feedstock inlet; 2. Catalytic cracking reaction; 3. Settler; 4. Reactor oil and gas outlet.

[0041] 5. Regenerator slide valve; 6. Regenerator; 7. Oxygen gas inlet; 8. Second regeneration zone; 9. First regeneration zone; 10. Flue gas outlet; 11. Energy recovery separation; 12. CO product outlet unit.

[0042] 13 Other flue gas components 14 Regeneration slide valve 15 CO2 inlet

[0043] exit

[0044] 21 Catalytic cracking feedstock; 22 Riser reactor; 23 Second settling tank; 24 Reaction oil / gas oil

[0045] 25 Second regenerator slide valve 26 Second regenerator 27 Regenerated flue gas 28 Regenerated gas inlet 29 Second regeneration slide valve Detailed Implementation

[0046] The present application will now be described in further detail with reference to the accompanying drawings and embodiments. Through these descriptions, the features and advantages of the present application will become clearer and more apparent.

[0047] The term “exemplary” as used herein means “serving as an example, embodiment, or illustration.” Any embodiment illustrated herein as “exemplary” is not necessarily to be construed as superior to or better than other embodiments. Although various aspects of embodiments are shown in the accompanying drawings, the drawings are not necessarily drawn to scale unless specifically indicated otherwise.

[0048] Furthermore, the technical features involved in the different embodiments of this application described below can be combined with each other as long as they do not conflict with each other.

[0049] This invention relates to a method for regenerating spent catalyst from catalytic cracking and producing CO, comprising the following steps:

[0050] (1) The hydrocarbon feedstock and the catalytic cracking catalyst are brought into contact in the catalytic cracking reactor and the catalytic cracking reaction is carried out to separate the reaction oil and gas and the ungenerated catalyst with carbon deposits.

[0051] (2) The regenerator is provided with a first regeneration zone and a second regeneration zone connected from top to bottom, so that the catalyst to be generated passes through the first regeneration zone and the second regeneration zone in sequence after stripping to perform first regeneration and second regeneration respectively, to obtain regenerated catalyst and flue gas.

[0052] The first regeneration zone is a bubble bed, and the second regeneration zone is a rapid regeneration bed;

[0053] CO2 is introduced into the lower part of the first regeneration zone, so that the catalyst to be regenerated entering the first regeneration zone comes into contact with CO2 and the second flue gas from the second regeneration zone to perform the first regeneration;

[0054] Oxygen-containing gas is introduced into the lower part of the second regeneration zone to contact the semi-regenerated agent that has undergone the first regeneration and perform the second regeneration.

[0055] The regeneration gas includes CO2 introduced into the lower part of the first regeneration zone and the oxygen-containing gas introduced into the lower part of the second regeneration zone;

[0056] The oxygen-containing gas introduced into the lower part of the second regeneration zone has an oxygen volume ratio greater than or equal to 22%; the regeneration temperature of the first regeneration is 700-800℃;

[0057] (3) At least a portion of the regenerated catalyst is returned to the catalytic cracking reactor for recycling, and the flue gas is drawn out from the top of the regenerator and then separated to obtain CO product.

[0058] It should be noted that in step (1), the separated reaction oil and gas can be sent to a subsequent separation system to obtain various catalytic cracking products. After separation by the subsequent separation system, fractions such as dry gas, liquefied petroleum gas, stabilized gasoline, and catalytic diesel can be obtained. The separation method can be a conventional technique in the field, and this invention does not limit it, so it will not be described in detail here. The catalyst to be generated comes from the catalytic cracking reactor of the hydrocarbon feedstock.

[0059] In step (2), the catalyst to be generated first enters the first regeneration zone and flows downward, where it comes into countercurrent contact with CO2 introduced from the lower part of the first regeneration zone and the second flue gas from the second regeneration zone for the first regeneration, resulting in flue gas and a semi-regenerating agent. The resulting semi-regenerating agent continues to flow downward to the second regeneration zone, where it comes into countercurrent contact with oxygen-containing gas introduced from the lower part of the second regeneration zone for the second regeneration, resulting in a regenerated catalyst and a second flue gas. The second flue gas entering the first regeneration zone is the gas resulting from the reaction of oxygen-containing gas and the semi-regenerating agent. The CO2 introduced from the lower part of the first regeneration zone and the oxygen-containing gas introduced from the lower part of the second regeneration zone form the regeneration gas or regeneration atmosphere of the regenerator.

[0060] In step (3), the regenerated catalyst can be entirely recycled back to the catalytic cracking reactor. At least a portion of the catalytic cracking catalyst used in the catalytic cracking reaction is regenerated catalyst, preferably all of it. Preferably, the method of the present invention further includes degassing the regenerated catalyst obtained from the second regeneration before returning it to the catalytic cracking reactor for recycling. An internal or external heat exchanger can be installed in the regenerator, and the type, connection, and operation of the heat exchanger are well known to those skilled in the art. The flue gas obtained from the regenerator can be separated to obtain CO product. The separation method for obtaining CO product from the flue gas can be chemical absorption, membrane separation, pressure swing adsorption, cryogenic separation, COSORB separation, or other separation and purification methods well known to those skilled in the art, preferably chemical absorption. Before separating CO from the flue gas, the flue gas can be purified to remove impurities such as sulfides and nitrogen oxides.

[0061] It should be noted that the first regeneration zone uses a bubbling bed, which achieves the following effects: while ensuring the fluidization state of the catalyst, it increases the ratio of coke to oxygen, increases the catalyst residence time, and promotes more incomplete combustion of coke to generate CO, thereby reducing the amount of CO2 generated by coke combustion in the second regeneration zone. The second regeneration zone uses a fast bed, which can improve coke burning efficiency, rapidly and completely convert the coke on the semi-regenerated catalyst under oxygen-rich conditions, and effectively restore the catalyst activity.

[0062] More importantly, the inventors of this application have discovered during years of research and development that in the method of this application, oxygen-containing gas is introduced into the lower part of the second regeneration zone, CO2 is introduced into the lower part of the first regeneration zone, and the first regeneration zone is simultaneously made into a bubbling bed and the second regeneration zone into a rapid bed, which significantly improves the CO selectivity.

[0063] It should be noted that, in the method for regenerating and producing CO based on catalytic cracking spent catalyst of the present invention, under the premise that gas is introduced into the lower part of the first regeneration zone and the second regeneration zone as above, and the bed type of the first regeneration zone and the second regeneration zone are controlled simultaneously as above, the regeneration temperature of the first regeneration is 700-800°C, so that the coke on the spent catalyst is converted into flue gas with higher CO selectivity; the regeneration temperature of the first regeneration is preferably 740-780°C, which can further improve CO selectivity.

[0064] According to a specific embodiment of the method for regenerating and producing CO based on spent catalyst from catalytic cracking according to the present invention, the bed density of the bubbling bed is 300-700 kg / m³. 3 ; and / or,

[0065] The bed density of the rapid bed is 120-300 kg / m³. 3 .

[0066] It should be noted that the preferred bed density of the bubble bed is 450–650 kg / m³. 3 The preferred bed density of the rapid bed is 180–250 kg / m³. 3 .

[0067] It should be noted that in the method of regenerating and producing CO based on catalytic cracking spent catalyst of the present invention, by controlling the bed density of the bubbling bed and the bed density of the fast bed as described above, the coke on the catalytic cracking spent catalyst can be better converted into carbon monoxide, so that the coke can be converted into flue gas with higher CO selectivity, which significantly reduces CO2 emissions. Moreover, by changing the regeneration coke burning method to produce carbon monoxide, tail combustion can be effectively reduced and the catalyst deactivation rate can be slowed down.

[0068] According to a specific embodiment of the method for regenerating and producing CO based on catalytic cracking spent catalyst according to the present invention, the conditions for the first regeneration include: the apparent linear velocity of the gas is 0.1 to 1 m / s, and the average residence time of the catalyst is 0.6 to 20 minutes.

[0069] It should be noted that the average residence time of the catalyst in the first regeneration zone is preferably 5 to 15 minutes.

[0070] According to a specific embodiment of the method for regenerating and producing CO based on catalytic cracking spent catalyst according to the present invention, the volume percentage of CO2 introduced into the lower part of the first regeneration zone in the regeneration gas is 1-50%, preferably 2-15%.

[0071] It should be noted that by controlling the conditions of the first regeneration as described above, and by controlling the amount of CO2 introduced into the lower part of the first regeneration zone as described above, the present invention facilitates the conversion of the carbon deposits on the catalyst to flue gas with higher CO selectivity.

[0072] According to a specific embodiment of the method for regenerating and producing CO based on catalytic cracking spent catalyst according to the present invention, the conditions for the second regeneration include: a regeneration temperature of 600-700°C, a gas apparent linear velocity of 0.8-4 m / s, and an average catalyst residence time of 0.6-15 minutes.

[0073] It should be noted that in the second regeneration, the regeneration temperature is preferably 650-690℃, and the average residence time of the catalyst is preferably 2-10 minutes.

[0074] According to a specific embodiment of the method for regenerating and producing CO based on catalytic cracking spent catalyst according to the present invention, the oxygen-containing gas introduced into the lower part of the second regeneration zone is a mixture of CO2 and O2.

[0075] The total amount of CO2 introduced into the lower part of the first regeneration zone and the total amount of CO2 introduced into the lower part of the second regeneration zone accounts for 1-89% of the volume of the regeneration gas, preferably 60-80%.

[0076] It should be noted that the regeneration gas in the regenerator does not contain N2 and / or air, but uses oxygen and CO2 as the regeneration gas, and some CO2 is converted into CO; nitrogen is not introduced, and a relatively simple method can be used to separate and obtain CO products with high purity, while also playing a role in enriching CO2, which is beneficial to carbon capture and utilization.

[0077] It should be noted that by controlling the conditions of the second regeneration as described above, controlling the proportion of the total amount of CO2 introduced into the two regeneration zones in the regeneration gas (which simultaneously controls the oxygen content in the regeneration gas), and the proportion of CO2 introduced into the first regeneration zone in the regeneration gas, the semi-regenerator can be completely regenerated in the second regeneration zone without affecting the catalytic cracking reaction activity. Furthermore, it is beneficial to achieve better incomplete combustion, reduce combustion heat release, alleviate the problem of excess heat in the catalytic unit, and significantly increase the CO content in the flue gas, which is conducive to the further purification and application of CO. The CO selectivity can reach more than 81%.

[0078] In one specific embodiment of the method for regenerating and producing CO based on catalytic cracking spent catalyst according to the present invention, the volume ratio of the second regeneration zone to the first regeneration zone is 1:(1-10).

[0079] It should be noted that the volume ratio of the second regeneration zone to the first regeneration zone is preferably 1:2-6. This ratio helps to prolong the residence time of the spent catalyst in the first regeneration zone, allowing more coke to burn and generate CO, thus reducing the carbon content on the semi-regenerated catalyst.

[0080] According to a specific embodiment of the method for regenerating and producing CO based on catalytic cracking spent catalyst according to the present invention, in step (1), the hydrocarbon feedstock includes petroleum hydrocarbons and / or other mineral oils, wherein the petroleum hydrocarbons are selected from one or more combinations of gasoline, diesel, vacuum wax oil, atmospheric wax oil, coking wax oil, deasphalted oil, vacuum residue, atmospheric residue, extracted oil and inferior recycled oil, and the other mineral oils are selected from one or more combinations of coal liquefaction oil, oil sands oil and shale oil.

[0081] It should be noted that the method of the present invention for regenerating and producing CO based on catalytic cracking spent catalyst has a wide range of applicability. The spent catalysts with carbon deposits produced by catalytic cracking of the above-mentioned various hydrocarbon feedstocks can be converted into flue gas with high CO selectivity through the above-mentioned regeneration process.

[0082] According to a specific embodiment of the method for regenerating and producing CO based on catalytic cracking spent catalyst according to the present invention, in step (1), the conditions of the catalytic cracking reaction include: a reaction temperature of 450-700°C, a time of 1-10 seconds, and a catalyst-to-oil ratio of (1-100):1.

[0083] It should be noted that the reaction temperature is preferably 500-650℃, more preferably 550-630℃; the reaction time is preferably 2-5 seconds; and the catalyst-to-oil ratio (the weight ratio of catalytic cracking catalyst to hydrocarbon feedstock) is preferably 5-30:1.

[0084] In this invention, as a variation, water vapor can also be injected into the catalytic cracking reactor. The water vapor is preferably injected in the form of atomized steam, and the weight ratio of the injected water vapor to the hydrocarbon feedstock can be 0.01 to 1:1, preferably 0.05 to 0.5:1.

[0085] The catalytic cracking catalyst used in the catalytic cracking reaction may comprise 15–65 wt% natural minerals, 10–30 wt% inorganic oxides, and 25–75 wt% zeolite. The zeolite, as the active component, is preferably one or a mixture of more than one of γ-zeolite, mordenite, β-zeolite, and zeolites with an MFI structure (e.g., ZSM series zeolites and / or ZRP zeolite). The natural minerals are selected from one or more of kaolinite, hydrous kaolinite, montmorillonite, diatomite, attapulgite, sepiolite, halloysite, hydrotalcite, bentonite, and rettoite. The inorganic oxides are selected from one or more of silica, alumina, zirconium oxide, titanium dioxide, and amorphous silica-alumina.

[0086] According to a specific embodiment of the method for regenerating and producing CO based on catalytic cracking spent catalyst according to the present invention, the catalytic cracking reactor is a riser reactor, a fluidized bed reactor, or a combination of both.

[0087] It should be noted that the catalytic cracking reactor can be a conventional catalytic cracking riser reactor, fluidized bed reactor, or a combination thereof, as known to those skilled in the art. For example, a catalytic cracking riser reactor connected in series with a fluidized bed reactor. The riser reactor can be selected from a constant-diameter riser reactor and / or a constant-linear-velocity riser reactor, preferably using a constant-diameter riser. The fluidized bed reactor is located downstream of the riser reactor and connected to the riser reactor outlet. The riser reactor includes, from bottom to top, a pre-rise section and at least one reaction zone. To ensure sufficient reaction of the feedstock and depending on different target product quality requirements, there can be 2 to 8 reaction zones, preferably 1 to 3.

[0088] The method for regenerating and producing CO based on catalytic cracking spent catalyst described in this invention can be implemented based on a system for regenerating and producing CO based on catalytic cracking spent catalyst, which includes a catalytic cracking reaction unit, a regenerator 6, and an energy recovery and separation unit 11.

[0089] The catalytic cracking reaction unit includes a catalytic cracking reactor 2 and a settling tank 3. The catalytic cracking reactor 2 is provided with a hydrocarbon feedstock inlet 1, a catalyst inlet and an oil outlet. The oil outlet of the catalytic cracking reactor 2 is connected to the inlet of the settling tank 3. The settling tank 3 is provided with a catalyst outlet and a reaction oil and gas outlet 4.

[0090] The outlet of the catalyst to be generated in the settling tank 3 is connected to the inlet of the catalyst to be generated in the regenerator 6 through a catalyst pipeline, and the catalyst pipeline is equipped with a catalyst slide valve 5.

[0091] The regenerator 6 is provided with a first regeneration zone 9 and a second regeneration zone 8 connected from top to bottom. The lower part of the first regeneration zone 9 is provided with a CO2 inlet 15, and the lower part of the second regeneration zone 8 is provided with an oxygen-containing gas inlet 7.

[0092] The first regeneration zone 9 is a bubble bed, and the second regeneration zone 8 is a rapid regeneration bed;

[0093] The second regeneration zone 8 is provided with a regenerator outlet, which is connected to the catalyst inlet of the catalytic cracking reactor 2 through a regenerator pipeline, and the regenerator pipeline is provided with a regeneration slide valve 14;

[0094] The regenerator 6 is provided with a flue gas outlet 10 at the top, which is connected to the inlet of the energy recovery and separation unit 11. The energy recovery and separation unit 11 is also provided with a CO product outlet 12 and other flue gas component outlets 13.

[0095] It should be noted that the method for producing CO based on the regeneration of spent catalyst in catalytic cracking, or the system for producing CO based on the regeneration of spent catalyst in catalytic cracking, of the present invention not only reduces carbon dioxide emissions from the catalytic unit and produces CO, realizing the transformation of waste into treasure and the full utilization of resources, thus improving the economic efficiency of the catalytic cracking unit; at the same time, by using CO as a raw material for subsequent chemical processes, it saves fossil resources such as coal, oil, and methane used to produce CO, reduces energy consumption and investment, reduces pollution, and improves the economic and social benefits of the petrochemical industry.

[0096] The present invention will be further described in detail below through examples, but these examples are not intended to limit the invention. In the following examples, unless otherwise specified, the experimental instruments and raw materials involved are all commercially available products.

[0097] The raw material oil used in the examples and comparative examples is Anqing wax oil, the properties of which are shown in Table 1.

[0098] The catalytic cracking catalyst used in the examples and comparative examples is commercially known as CDOS (China Petrochemical Catalyst Co., Ltd. Changling Branch).

[0099] Table 1

[0100]

[0101] As attached Figure 1As shown, the catalytic cracking feedstock enters from the hydrocarbon feedstock inlet 1 at the bottom of the catalytic cracking reactor 2 (riser reactor), where it reacts with the regenerated catalyst. The reacting oil and gas and the catalyst move upwards to the settling tank 3 for gas-solid separation. The separated reacting oil and gas go to the subsequent absorption and stabilization system through the reacting oil and gas outlet 4. The regenerated catalyst enters the first regeneration zone 9 of the regenerator 6 through the regeneration slide valve 5, where it undergoes first regeneration by contacting the second flue gas from the second regeneration zone 8 and the CO2 introduced from the lower part of the first regeneration zone 9 by the CO2 inlet 15, resulting in a semi-regenerated catalyst. The semi-regenerated catalyst moves downwards into the second regeneration zone 8, where it undergoes second regeneration by contacting the oxygen-containing gas (a mixture of CO2 and O2) entering through the oxygen-containing gas inlet 7, resulting in a regenerated catalyst. The regenerated catalyst returns to the bottom of the catalytic cracking reactor 2 (riser reactor) through the regeneration slide valve 14 to react with the feedstock. After the regenerated flue gas flows out of the flue gas outlet 10, it is separated into gas and solid and then led out of the regenerator 6 to the subsequent energy recovery and separation unit 11. After separation, carbon monoxide (CO product output 12) and other flue gas components (other flue gas components output 13) are obtained. The first regeneration zone 9 is a bubbling bed, and the second regeneration zone 8 is a fast bed.

[0102] Examples 1-5

[0103] According to the appendix Figure 1 The process was tested, and the relevant operating conditions and products are listed in Table 2.

[0104] Comparative Examples 1, 2 and 4

[0105] According to the appendix Figure 1 The process was tested, and the relevant operating conditions and products are listed in Table 3.

[0106] Comparative Examples 3 and 5

[0107] According to the appendix Figure 2 The process was tested. Catalytic cracking feedstock 21 entered from the bottom of riser reactor 22 and reacted with the regenerated catalyst. The reacting oil and gas and catalyst rose to the second settling tank 23 for gas-solid separation. The separated reacting oil and gas 24 went to the subsequent separation system. The spent catalyst entered the second regenerator 26 through the second spent catalyst slide valve 25 and was regenerated by contacting the regeneration gas. The regeneration gas entered the second regenerator 26 through the regeneration gas inlet 28. The regeneration flue gas 27 was led out of the second regenerator 26 to the subsequent energy recovery system. The regenerated catalyst returned to the bottom of riser reactor 22 through the second regeneration slide valve 29 to react with the catalytic cracking feedstock 21. The relevant operating conditions and products are listed in Table 3.

[0108] In the following examples and comparative examples, the method for calculating CO selectivity is as follows:

[0109]

[0110] In the CO selectivity calculation formula, the amount of CO generated represents the amount of CO in the flue gas obtained from the regenerator, and the amount of carbon in the coke represents the amount of carbon in the coke on the catalyst to be regenerated or in the coke deposits entering the regenerator.

[0111] Table 2

[0112]

[0113] Note: The regeneration gas includes CO2 introduced into the first regeneration zone and O2 and CO2 introduced into the second regeneration zone. The volume percentage of supplementary CO2 in the regeneration gas indicates the volume percentage of CO2 introduced into the first regeneration zone in the regeneration gas.

[0114] Table 3

[0115]

[0116]

[0117] As can be seen from the results of the embodiments, the method of the present invention has the advantage of significantly reducing carbon dioxide emissions and producing carbon monoxide.

[0118] In the description of this application, it should be noted that the terms "upper", "lower", "inner", "outer", "front", "rear", "left", "right", etc., indicate the orientation or positional relationship based on the orientation or positional relationship in the working state of this application. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0119] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. Those skilled in the art can understand the specific meaning of these terms in this application based on the specific circumstances.

[0120] The present application has been described above with reference to preferred embodiments; however, these embodiments are merely exemplary and illustrative. Various substitutions and modifications can be made to the present application based on these embodiments, all of which fall within the protection scope of the present application.

Claims

1. A method for producing CO based on the regeneration of spent catalyst from catalytic cracking, characterized in that, Includes the following steps: (1) To bring hydrocarbon feedstock and catalytic cracking catalyst into contact in a catalytic cracking reactor and carry out catalytic cracking reaction, and to separate the reacted oil and gas and the spent catalyst with carbon deposits; (2) The regenerator is provided with a first regeneration zone and a second regeneration zone connected from top to bottom, so that the catalyst to be generated passes through the first regeneration zone and the second regeneration zone in sequence after stripping to perform the first regeneration and the second regeneration respectively, so as to obtain the regenerated catalyst and flue gas; The first regeneration zone is a bubble bed, and the second regeneration zone is a rapid regeneration bed; CO2 is introduced into the lower part of the first regeneration zone, so that the catalyst to be regenerated entering the first regeneration zone comes into contact with CO2 and the second flue gas from the second regeneration zone to perform the first regeneration; Oxygen-containing gas is introduced into the lower part of the second regeneration zone to contact the semi-regenerated agent that has undergone the first regeneration and perform the second regeneration. The regeneration gas includes CO2 introduced into the lower part of the first regeneration zone and the oxygen-containing gas introduced into the lower part of the second regeneration zone; The total volume percentage of CO2 in the oxygen-containing gas introduced into the lower part of the first regeneration zone and the lower part of the second regeneration zone is 60-80% of the total volume of the regeneration gas. The oxygen volume percentage of the oxygen-containing gas introduced into the lower part of the second regeneration zone is greater than or equal to 22%; the regeneration temperature of the first regeneration is 700-800℃; (3) At least a portion of the regenerated catalyst is returned to the catalytic cracking reactor for recycling, and the flue gas is drawn out from the top of the regenerator and then separated to obtain CO product.

2. The method for producing CO based on the regeneration of spent catalyst from catalytic cracking according to claim 1, characterized in that, The density of the bubbling bed is 300~700 kg / m³. 3 ; and / or, The bed density of the rapid bed is 120~300 kg / m³. 3 .

3. The method for producing CO based on the regeneration of spent catalyst from catalytic cracking according to claim 1, characterized in that, The conditions for the first regeneration include: an apparent gas linear velocity of 0.1 to 1 m / s and an average catalyst residence time of 0.6 to 20 minutes.

4. The method for producing CO based on the regeneration of spent catalyst from catalytic cracking according to claim 1, characterized in that, The volume percentage of CO2 introduced into the lower part of the first regeneration zone in the regeneration gas is 1-50%.

5. The method for producing CO based on the regeneration of spent catalyst from catalytic cracking according to claim 4, characterized in that, The volume percentage of CO2 introduced into the lower part of the first regeneration zone in the regeneration gas is 2-15%.

6. The method for producing CO based on the regeneration of spent catalyst from catalytic cracking according to claim 1, characterized in that, The conditions for the second regeneration include: a regeneration temperature of 600-700℃, a gas apparent linear velocity of 0.8-4 m / s, and an average catalyst residence time of 0.6-15 minutes.

7. The method for producing CO based on the regeneration of spent catalyst from catalytic cracking according to claim 1, characterized in that, The oxygen-containing gas introduced into the lower part of the second regeneration zone is a mixture of CO2 and O2.

8. The method for producing CO based on the regeneration of spent catalyst from catalytic cracking according to claim 1, characterized in that, The volume ratio of the second regeneration zone to the first regeneration zone is 1:(1-10).

9. The method for producing CO based on the regeneration of spent catalyst from catalytic cracking according to claim 1, characterized in that, In step (1), the hydrocarbon feedstock includes petroleum hydrocarbons and / or other mineral oils. The petroleum hydrocarbons are selected from one or more of gasoline, diesel, vacuum wax oil, atmospheric wax oil, coking wax oil, deasphalted oil, vacuum residue, atmospheric residue, extracted oil, and inferior recycled oil. The other mineral oils are selected from one or more of coal liquefaction oil, oil sands oil, and shale oil.

10. The method for producing CO based on the regeneration of spent catalyst from catalytic cracking according to claim 1, characterized in that, In step (1), the conditions for the catalytic cracking reaction include: a reaction temperature of 450 to 700°C, a time of 1 to 10 seconds, and a catalyst-to-oil ratio of (1 to 100):

1.

11. The method for producing CO based on the regeneration of spent catalyst from catalytic cracking according to claim 1, characterized in that, The catalytic cracking reactor is a riser reactor, a fluidized bed reactor, or a combination of both.

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