Cracking apparatus and cracking method

Abstract

The embodiment of the present application discloses a cracking device and a cracking method. The cracking device comprises a first reactor, a first reaction zone is formed in the first reactor; a second reactor, one end of the first reactor is located inside the second reactor, a second reaction zone is formed in the second reactor; a sleeve, the sleeve is sleeved on the one end of the first reactor located inside the second reactor; an oil agent distributor, the oil agent distributor is arranged between the sleeve and the first reactor; and a catalyst distributor, the catalyst distributor is arranged on the upper part of the sleeve. Through the cracking device of the embodiment of the present application, the reaction temperature of each reaction zone is controlled by the circulating amount of the regenerated catalyst / solid heat carrier entering each reaction zone, and the purpose of independently controlling the reaction temperature of different reaction zones is achieved. The partition reaction according to the respective reaction mechanism requirements is realized for different properties of raw materials, the temperature of different reaction zones is independently controlled, the yield of by-products such as dry gas and coke can be significantly reduced, and the yield and selectivity of low-carbon olefins are improved.

Description

TECHNICAL FIELD

[0001] The embodiment of the present application relates to the technical field of petrochemical reaction, in particular to a cracking device and a cracking method. BACKGROUND

[0002] The cracking in petrochemical industry refers to a process that high-temperature cracking of petroleum hydrocarbons is carried out by using a catalyst or a solid heat carrier to produce ethylene, propylene, butene and other low-carbon olefins, and simultaneously produce light aromatic hydrocarbons, which is a key technology for the refining and chemical transformation and upgrading of a refinery. Compared with catalytic cracking, the cracking adopts a higher reaction temperature and a larger catalyst-to-oil ratio, and the reaction condition is more severe, so that the conventional catalytic cracking riser reactor cannot be simply used, and the design and optimization of the cracking method and the reaction device have been the focus of attention of all parties.

[0003] The Deep Catalytic Cracking (DCC) process developed by the Petrochemical Research Institute of SINOPEC (hereinafter referred to as SINOPEC) takes heavy oil as a raw material and takes the production of propylene as a main purpose, and the characteristics are that a riser + dense phase fluidized bed combined reactor technology is adopted, a paraffin-based raw material is preferred, a higher reaction temperature is adopted in the riser reactor, a low air speed process condition is adopted in the dense bed, and the propylene yield is 15-22%. The problem of the DCC process is that the temperatures of the two reaction zones (the riser is a first reaction zone, and the dense phase fluidized bed is a second reaction zone) cannot be independently controlled, in order to ensure the reaction temperature of the second reaction zone, the temperature of the heavy oil reaction of the first reaction zone is very high, which causes high dry gas and coke yields.

[0004] On the basis of the DCC process, the SINOPEC developed the DCC-plus process with high propylene selectivity. The DCC-plus process adds a second riser (a third reaction zone) to the dense phase fluidized bed (a second reaction zone) to supplement the regenerated catalyst, the temperature of the second reaction zone can be independently controlled, the outlet temperature of the main riser (the first reaction zone) is reduced, and the dry gas and coke yields are reduced. Although the DCC-Plus process solves the problem of the independent temperature control of the second reaction zone of the DCC, the high-activity catalyst returned by the third reaction zone cannot be uniformly distributed on the large cross section of the second reaction zone, which causes the activity of the catalyst in the second reaction zone to be different, and affects the olefin yield and selectivity. SUMMARY

[0005] The present application aims at least to solve one of the problems in the prior art or related art.

[0006] To this end, the first aspect of the present application provides a cracking device.

[0007] The second aspect of the present application provides a cracking method.

[0008] Therefore, according to the first aspect of the embodiment of the present application, a cracking device is provided, which comprises:

[0009] a first reactor, a first reaction zone being formed in the first reactor;

[0010] a second reactor, one end of the first reactor being located inside the second reactor, a second reaction zone being formed in the second reactor;

[0011] a sleeve, the sleeve being sleeved on the one end of the first reactor located inside the second reactor, a gap being left between the outer wall of the sleeve and the second reactor;

[0012] an oil agent distributor, the oil agent distributor being arranged between the sleeve and the first reactor.

[0013] In an embodiment, the oil agent distributor comprises:

[0014] a distribution pipe, a first through hole being formed in the distribution pipe; wherein the oil agent distributor is multiple.

[0015] In an embodiment, the first reactor comprises a fluidized bed reactor or a riser reactor; the second reactor is a dense phase fluidized bed.

[0016] In an embodiment, the cracking device further comprises:

[0017] a riser, the riser being connected to the one end of the first reactor away from the second reactor.

[0018] In an embodiment, the cracking device further comprises:

[0019] a first fluidizing ring, a second through hole being formed in the first fluidizing ring, the first fluidizing ring being arranged in the second reactor, between the sleeve and the second reactor;

[0020] a second fluidizing ring, a third through hole being formed in the second fluidizing ring, the second fluidizing ring being arranged on the one end of the first reactor close to the second reactor;

[0021] a steam providing device, the steam providing device being communicated with the first fluidizing ring and the second fluidizing ring.

[0022] In an embodiment, the cracking device further comprises:

[0023] a first feeding pipe, the first feeding pipe being communicated with the first reactor;

[0024] a conveying pipe, the conveying pipe being connected to the one end of the second reactor away from the first reactor;

[0025] a stripping part, the conveying pipe passing through the stripping part;

[0026] a settler, the settler being connected to the other end of the conveying pipe;

[0027] a separator disposed in the settler;

[0028] a spent inclined pipe communicated with the stripping section.

[0029] In an embodiment, the cracking device further comprises:

[0030] a catalyst regeneration system communicated with the spent inclined pipe.

[0031] In an embodiment, the cracking device further comprises:

[0032] a first regenerated inclined pipe communicated with the first reactor and the catalyst regeneration system.

[0033] In an embodiment, the cracking device further comprises:

[0034] a catalyst distributor disposed in the second reactor, an output end of the catalyst distributor being disposed towards the sleeve.

[0035] In an embodiment, the cracking device further comprises:

[0036] a second regenerated inclined pipe communicated with the catalyst distributor;

[0037] a second feed pipe communicated with the second reactor, located between the catalyst distributor and the first reactor vessel; or

[0038] a third reaction zone riser communicated with the catalyst distributor;

[0039] a third regenerated inclined pipe communicated with the third reaction zone riser;

[0040] a third feed pipe communicated with the third reaction zone riser.

[0041] According to a second aspect of the embodiments of the present application, a cracking method is provided, which is used in the cracking device of any of the above technical solutions, and comprises:

[0042] by controlling the supply speed of the raw oil, the residence time of the raw oil in the first reaction zone is 1s to 2s, and the residence time of the oil gas in the second reaction zone is 2s to 5s;

[0043] wherein the reaction temperature of the first reaction zone is 550℃ to 600℃, and the reaction temperature of the second reaction zone is 630℃ to 730℃.

[0044] Compared with the prior art, the application has at least the following beneficial effects: the cracking device provided by the application comprises a first reactor, a second reactor, a sleeve and an oil distributor. In use, raw oil, high-temperature high-activity catalyst and solid heat carrier are transported into the first reactor, and a heavy oil cracking reaction is performed in a first reactor zone of the first reactor. A lower reaction severity and a shorter residence time can be used, and mainly intermediate components such as liquefied gas, gasoline and diesel oil are generated, and the yield of dry gas and coke is controlled. After the cracking reaction in the first reaction zone, the high-temperature high-activity catalyst becomes low-temperature low-activity catalyst, and the low-temperature low-activity catalyst and the solid heat carrier are transported into the second reactor through the first reactor. In this process, the sleeve and the oil distributor can preliminarily separate the oil gas in the material supplied from the first reactor to the second reactor from the low-temperature low-activity catalyst and the low-temperature solid heat carrier. The oil gas is supplied into the second reactor through the oil distributor, and part of the low-temperature low-activity catalyst and the low-temperature solid heat carrier are blocked by the oil distributor. The oil gas in the second reactor can be mixed with the high-temperature high-activity catalyst / high-temperature solid heat carrier newly added into the second reactor to form a high-severity reaction zone for deep cracking of intermediate components such as C4, gasoline and diesel oil. The low-temperature low-activity catalyst and the low-temperature solid heat carrier preliminarily separated by the sleeve and the oil distributor flow upward from the inside and the outside of the sleeve. In this way, at least part of the low-temperature low-activity catalyst does not mix with the high-temperature high-activity catalyst newly added into the second reactor, so that the reaction efficiency in the second reactor can be ensured, and the efficiency of the petroleum chemical reaction is improved. BRIEF DESCRIPTION OF DRAWINGS

[0045] Various other advantages and benefits will become apparent to those of ordinary skill in the art upon reading the following detailed description of the preferred embodiments. The accompanying drawings are included to provide a description of the preferred embodiments and are not intended to limit the scope of the application. Moreover, the same reference numerals in the various drawings indicate the same or similar components. In the drawings:

[0046] Figure 1 a schematic structural diagram of a cracking device according to an embodiment of the application;

[0047] Figure 2 a schematic structural diagram of a cracking device according to another embodiment of the application.

[0048] wherein, Figure 1 and Figure 2 the correspondence between the reference numerals in the drawings and the component names is as follows:

[0049] 1 riser, 2 first feed pipe, 3 first reactor, 4 second fluidizing ring, 5 first fluidizing ring, 6 sleeve, 7 oil distributor, 8 transfer pipe, 9 stripping section, 10 settler, 11 separator, 12 second reactor, 13 catalyst distributor, 14 third reaction zone riser, 15 third feed pipe, 16 spent catalyst slanted pipe, 17 first regenerated catalyst slanted pipe, 18 third regenerated catalyst slanted pipe, 19 second regenerated catalyst slanted pipe, 20 second feed pipe. DETAILED DESCRIPTION

[0050] In order to better understand the above technical solutions, the technical solutions of the embodiments of the present application are described in detail below through the drawings and specific embodiments. It should be understood that the specific features in the embodiments of the present application and the specific embodiments are detailed descriptions of the technical solutions of the embodiments of the present application, and are not limitations of the technical solutions of the present application. In the case of no conflict, the technical features in the embodiments of the present application and the specific embodiments can be combined with each other.

[0051] As shown in Figure 1 and Figure 2 , in view of this, according to the first aspect of the embodiments of the present application, a cracking device is provided, comprising: a first reactor 3, a first reaction zone is formed in the first reactor 3; a second reactor 12, one end of the first reactor 3 is located inside the second reactor 12, a second reaction zone is formed in the second reactor 12; a sleeve 6, sleeved on the end of the first reactor 3 located inside the second reactor 12, a gap is left between the outer wall of the sleeve 6 and the second reactor 12; an oil distributor 7, arranged between the sleeve 6 and the first reactor 3.

[0052] The cracking device provided by the embodiments of the present application comprises a first reactor 3, a second reactor 12, a sleeve 6 and an oil distributor 7. In use, raw oil, high-temperature high-activity catalyst and solid heat carrier are transported into the first reactor 3, and a heavy oil cracking reaction is performed in a first reaction zone of the first reactor 3. A lower reaction severity and a shorter residence time can be used, and mainly intermediate components such as liquefied gas, gasoline and diesel oil are generated, and the dry gas and coke yields are controlled. After the cracking reaction in the first reaction zone, the high-temperature high-activity catalyst becomes low-temperature low-activity catalyst, and the low-temperature low-activity catalyst and the solid heat carrier are transported into the second reactor 12 through the first reactor 3. In this process, the sleeve 6 and the oil distributor 7 can preliminarily separate the oil gas from the low-temperature low-activity catalyst and the low-temperature solid heat carrier in the material supplied from the first reactor 3 to the second reactor 12. The oil gas is supplied into the second reactor 12 through the oil distributor 7, and part of the low-temperature low-activity catalyst and the low-temperature solid heat carrier are blocked by the oil distributor 7. The oil gas entering the second reactor 12 can be mixed with the high-temperature high-activity catalyst / high-temperature solid heat carrier newly added into the second reactor to form a high-severity reaction zone for deep cracking of intermediate components such as C4, gasoline and diesel oil. The low-temperature low-activity catalyst and the low-temperature solid heat carrier preliminarily separated by the sleeve 6 and the oil distributor 7 flow upward from the inside and the outside of the sleeve 6 under the action of the oil gas thrust. In this way, at least part of the low-temperature low-activity catalyst does not mix with the high-temperature high-activity catalyst newly added into the second reactor 12, so that the reaction efficiency in the second reactor 12 can be ensured, and the efficiency of the petroleum chemical reaction is improved.

[0053] In a feasible implementation, the oil distributor 7 comprises a plurality of distribution pipes, and the distribution pipes are provided with first through holes.

[0054] The oil distributor 7 comprises a distribution pipe provided with a first through hole. In use, as the raw oil is continuously input into the first reactor 3, after the oil gas is generated by the cracking reaction of the raw oil in the first reaction zone, the mixture of the oil gas, the low-temperature low-activity catalyst and the low-temperature solid heat carrier flows to the second reactor 12. In this process, the distribution pipe blocks the low-temperature low-activity catalyst and the low-temperature solid heat carrier, and the oil gas can pass through the distribution pipe into the second reactor 12 through the first through hole.

[0055] It can be understood that the oil agent distributor 7 can be multiple, the first through hole of the multiple oil agent distributors 7 is different in aperture and / or opening number, so that the multiple oil agent distributors 7 are different in blocking efficiency for the low-temperature low-activity catalyst and the low-temperature solid heat carrier, in actual production process, appropriate oil agent distributor 7 can be selected for assembly, so as to realize adjustment of the preliminary separation efficiency of the low-temperature low-activity catalyst and the low-temperature solid heat carrier.

[0056] In an implementable embodiment, the first reactor 3 comprises a fluidized bed reactor or a riser reactor; and the second reactor 12 is a dense phase fluidized bed.

[0057] The cracking device provided by the embodiment of the application is provided in a partitioned manner, wherein the first reaction zone adopts a riser reactor or a fluidized bed reactor + riser conveying section, is used for cracking reaction of heavy oil, adopts lower reaction severity and shorter residence time, mainly generates intermediate components such as liquefied gas, gasoline and diesel oil, and controls dry gas and coke yield. The oil agent distributor 7 is arranged at the end of the first reaction zone, and is used for distributing and preliminarily separating oil gas and low-temperature low-activity catalyst / low-temperature solid heat carrier. The sleeve 6 is arranged between the end of the first reaction zone and the second reaction zone, and forms an annular fluidized bed, part of the low-temperature low-activity catalyst flows upward from the inside of the sleeve 6, and part of the low-temperature low-activity catalyst flows upward from the outside of the sleeve 6, and the flow of the catalyst in the sleeve 6 can be adjusted by adjusting the flow of fluidizing steam outside the sleeve 6.

[0058] In an implementable embodiment, the second reactor 12 is a dense phase fluidized bed.

[0059] The second reaction zone adopts a dense phase fluidized bed type, the oil gas and catalyst / solid heat carrier rising in the annular fluidized bed sleeve 6 is mixed with high-temperature high-activity catalyst / high-temperature solid heat carrier to form a high-severity reaction zone, which is used for deep cracking of intermediate components such as C4, gasoline and diesel oil.

[0060] As shown in Figure 1 and Figure 2 In an implementable embodiment, the cracking device further comprises a lifter 1 connected to the end of the first reactor 3 away from the second reactor 12.

[0061] Through the arrangement of the lifter 1, the regenerated high-temperature high-activity catalyst and solid heat carrier can be conveniently conveyed into the first reactor 3.

[0062] In a feasible embodiment, the cracking device also includes: a first fluidizing ring 5, which is provided with a second through hole, and the first fluidizing ring 5 is arranged in the second reactor, located between the sleeve 6 and the second reactor; a second fluidizing ring 4, which is provided with a third through hole, and the second fluidizing ring 4 is arranged at one end of the first reaction container close to the second reactor 12; a steam supply device, which is connected to the first fluidizing ring 5 and the second fluidizing ring 4.

[0063] The cracking device also includes a first fluidizing ring 5, which is provided with a first through hole. The first through hole is arranged toward the second reactor. During use, the steam produced by the steam supply device can be sprayed toward the second reactor through the first through hole. The sprayed steam can drive the low-temperature, low-activity catalyst and the solid heat carrier to be transported to the second reaction zone through the gap between the sleeve and the second reactor 12. This part of the low-temperature, low-activity catalyst and solid heat carrier will not be mixed with the high-temperature, high-activity catalyst and solid heat carrier input into the second reaction zone at the first time, which can improve the reaction efficiency of the second reaction zone.

[0064] The cracking device also includes a second fluidizing ring 4, which is provided with a third through hole. The third through hole can be arranged toward the first reaction zone. Considering that the low-temperature and low-activity catalyst and solid heat carrier in the first reaction zone may accumulate at the connection between the first reactor 3 and the second reactor 12 through the arrangement of the oil distributor 7, the steam discharged through the third through hole can impact the stacked low-temperature and low-activity catalyst and solid heat carrier, so that the low-temperature and low-activity catalyst and solid heat carrier enter the second reactor through the gap between the sleeve and the first reactor 3 or the oil distributor 7, which is conducive to the circulation of the cracking reaction.

[0065] like Figure 1 and Figure 2 As shown, in a feasible embodiment, the cracking device also includes: a first feed pipe 2, connected to the first reactor 3; a conveying pipe 8, connected to the end of the second reactor 12 away from the first reactor 3; a stripping section, the transmission pipe passes through the stripping section; a settler 10, connected to the other end of the conveying pipe 8; a separator 11, arranged in the settler 10; and a waiting inclined pipe 16, connected to the stripping section.

[0066] The cracking device further includes a first feed pipe 2 , which facilitates the transportation of the crude oil into the first reactor 3 .

[0067] The cracking device also includes a conveying pipe 8, a stripping section, a settler 10 and a separator 11. After the oil and gas are deeply cracked in the second reaction zone, the oil and gas enter the rear conveying pipe 8 through the second reaction zone. The oil and gas and the catalyst are separated by the settler 10 and the separator 11. The oil and gas enter the rear separation system, and the catalyst is collected in the stripping section 9 and transported to the regenerator through the inclined pipe 16 for regeneration.

[0068] It is understandable that the high temperature and high activity catalyst after regeneration can be returned to the cracking unit for further reaction.

[0069] It can be understood that the separator 11 can be a cyclone separator.

[0070] In a feasible embodiment, the cracking device further comprises: a catalytic regeneration system connected to the inclined tube 16 to be regenerated.

[0071] The catalyst can be regenerated by setting up a catalytic regeneration system to form a high-temperature and high-activity catalyst, and the high-temperature and high-activity catalyst can be returned to the cracking device for further reaction.

[0072] In a feasible embodiment, the cracking device further includes: a first regeneration inclined pipe 17 connected to the first reactor 3 and the catalytic regeneration system.

[0073] The cracking device also includes a first regeneration inclined tube 17 , which can receive the high-temperature and high-activity catalyst output by the catalytic regeneration system. The high-temperature and high-activity catalyst can be transported to the first reactor 3 through the first regeneration inclined tube 17 .

[0074] like Figure 1 and Figure 2 As shown, in a feasible embodiment, the cracking device further includes: a catalyst distributor 13 , which is arranged in the second reactor, and the output end of the catalyst distributor 13 is arranged toward the sleeve 6 .

[0075] The cracking device also includes a catalyst distributor 13. The setting of the catalyst distributor 13 facilitates the uniform supply of high-temperature and high-activity catalyst to the second reactor 12. The catalyst distributor 13 is set toward the sleeve 6, which can enable the high-temperature and high-activity catalyst output through the catalyst distributor 13 to be mixed with the oil and gas input into the second reactor 12 through the first reactor 3 as soon as possible, thereby improving the efficiency of the cracking reaction.

[0076] In a feasible embodiment, the cracking device also includes: a second regeneration inclined pipe 19, connected to the catalyst distributor 13; a second feed pipe 20, connected to the second reactor 12, located between the catalyst distributor 13 and the first reaction vessel; or a third reaction zone riser 14, connected to the catalyst distributor 13; a third regeneration inclined pipe 18, connected to the third reaction zone riser 14; and a third feed pipe 15, connected to the third reaction zone riser 14.

[0077] The cracking device can further comprise a second regenerative inclined pipe 19, through which high-temperature and high-activity catalysts can be transported into the second reactor 12. It can be understood that the second regenerative inclined pipe 19 can also be connected to the catalytic regeneration system.

[0078] The cracking device can further comprise a second feed pipe 20, through which C4 and light gasoline can be recycled. The C4 and / or light gasoline can be mixed with the oil gas and part of the low-temperature catalyst separated by the first reaction zone outlet oil agent distributor 7 through the second feed pipe 20.

[0079] The cracking device can further comprise a third regenerative inclined pipe 18 and a third feed pipe 15, through which C4 and light gasoline can be recycled to improve the yield of low-carbon olefins. The recycling of C4 and light gasoline can be determined according to the appropriate transportation mode of the high-temperature regenerated catalyst / high-temperature solid heat carrier. The third regenerative inclined pipe 18 and the third feed pipe 15 can be externally provided, through which the high-temperature regenerated catalyst / high-temperature solid heat carrier can be lifted to the second reaction zone through the third regenerative inclined pipe 18 by gasification of C4 and light gasoline, and cracking reaction can be performed during the lifting process, and then the high-temperature regenerated catalyst / high-temperature solid heat carrier can be contacted with liquefied gas, gasoline, diesel and other intermediate components in the annular fluidized bed. At this time, the third reaction zone in the third regenerative inclined pipe 18 is a riser + annular fluidized bed. When the high-temperature regenerated catalyst / high-temperature solid heat carrier can be directly transported (without lifting) to the second reaction zone, the recycled C4 and light gasoline can be directly fed into the annular fluidized bed. At this time, the third reaction zone is an annular fluidized bed.

[0080] Through the cracking device of the embodiment of the present application, the reaction temperatures of the first / second reaction zones are respectively controlled by the circulation amounts of the regenerated catalyst / solid heat carrier entering the respective reaction zones, so that the purpose of independent control of the reaction temperatures of different reaction zones is achieved. Different raw materials with different properties can be subjected to partitioned reactions according to their respective reaction mechanisms, and the reaction temperatures of different reaction zones can be independently controlled, so that the yield of by-products such as dry gas and coke can be significantly reduced, the yield and selectivity of low-carbon olefins can be improved, and the yields of ethylene and propylene can be flexibly adjusted.

[0081] The embodiments of the present application can carry out partition reaction according to respective reaction mechanisms for different properties of raw materials, and realize independent control of temperature of different reaction zones. The oil distributor 7 is arranged, part of the low-temperature low-activity catalyst / low-temperature solid heat carrier is divided from the outside of the sleeve 6, the low-temperature low-activity catalyst / low-temperature solid heat carrier rising in the inside of the sleeve 6 is reduced, and the high-temperature high-activity catalyst / high-temperature solid heat carrier is mixed to easily form a high-severity reaction zone, and promote the cracking reaction; at the same time, the oil gas can be constrained on the cross section inside the sleeve 6, the high-temperature high-activity catalyst / high-temperature solid heat carrier is distributed along the cross section of the sleeve 6 above the sleeve 6, the high-temperature high-activity catalyst / high-temperature solid heat carrier sprayed downward is reversely contacted with the rising oil gas, and the back mixing effect is enhanced; the high-temperature high-activity catalyst / high-temperature solid heat carrier is distributed at the middle position of the cross section of the second reaction zone bed layer, the reaction efficiency reduction caused by the bed layer edge wall sliding effect can be reduced, and favorable conditions for high-severity reaction of the second reaction zone are created.

[0082] The first reaction zone adopts lower severity reaction conditions; the second reaction zone supplements the high-temperature high-activity catalyst / high-temperature solid heat carrier to form a high-severity reaction zone; the yield of by-products such as dry gas and coke can be significantly reduced, the yield and selectivity of low-carbon olefins are improved, and through adjustment of the temperature of the second reaction zone, flexible adjustment of the yield of ethylene and propylene is realized.

[0083] According to the second aspect of the embodiments of the present application, a cracking method is provided, which is used for the cracking device in any of the above technical solutions, and includes the following steps:

[0084] By controlling the supply speed of the raw material oil, the residence time of the raw material oil in the first reaction zone is 1s to 2s, and the residence time of the oil gas in the second reaction zone is 2s to 5s.

[0085] The reaction temperature of the first reaction zone is 550 DEG C to 600 DEG C, and the reaction temperature of the second reaction zone is 630 DEG C to 730 DEG C.

[0086] By the cracking method provided by the embodiment of the present application, combined with the cracking device of the embodiment of the present application, it is possible to carry out zone reactions according to the respective reaction mechanisms for raw materials of different properties, and realize independent control of the temperature of different reaction zones. An annular fluidized bed is set up, and part of the low-temperature and low-activity catalyst / low-temperature solid heat carrier can be diverted from the outside of the sleeve, and the low-temperature and low-activity catalyst / low-temperature solid heat carrier rising inside the sleeve is reduced, and it is easy to form a high-severity reaction zone by mixing with the high-temperature and high-activity catalyst / high-temperature solid heat carrier, thereby promoting the cracking reaction; at the same time, the oil and gas can be constrained on the internal cross-section of the sleeve, and the high-temperature and high-activity catalyst / high-temperature solid heat carrier is distributed along the sleeve cross-section above the sleeve, and the high-temperature and high-activity catalyst / high-temperature solid heat carrier sprayed downward is in reverse contact with the rising oil and gas, thereby enhancing the back-mixing effect; the high-temperature and high-activity catalyst / high-temperature solid heat carrier is distributed in the middle position of the cross-section of the bed in the second reaction zone, which can reduce the reaction efficiency drop caused by the sliding effect of the bed wall, and create favorable conditions for the high-severity reaction in the second reaction zone.

[0087] Example 1

[0088] See also Figure 1 The regenerated catalyst / solid heat carrier from the first regeneration inclined tube is lifted by the lifter, contacts, vaporizes and reacts with the first feed pipe, and enters the first reactor into the oil agent distributor at the outlet of the first reaction zone at the end, and distributes and preliminarily separates the oil and gas from the low-temperature, low-activity catalyst / low-temperature solid heat carrier. C4 and / or light gasoline contacts, vaporizes and reacts with the regenerated catalyst / solid heat carrier from the third regeneration inclined tube through the third feed pipe, and is distributed to the catalyst / solid heat carrier catalyst distributor through the third reaction zone lift pipe, and contacts and mixes with the oil and gas separated from the oil agent distributor at the outlet of the first reaction zone and part of the low-temperature catalyst. The other part of the low-temperature catalyst is transported to the second reactor through the external annular cavity of the sleeve and the first fluidized circulation outside the sleeve for contact and mixing, and the oil and gas are deeply cracked in the second reaction zone. The oil and gas enter the rear transmission pipe through the second reaction zone, and the oil and gas are separated from the catalyst through the separator. The oil and gas enter the rear separation system, and the catalyst is collected in the stripping section and transported to the regenerator through the waiting inclined tube for regeneration.

[0089] Example 2

[0090] See also Figure 2The regenerated catalyst / solid heat carrier from the first regeneration inclined pipe is lifted by the lifter, contacts, gasifies and reacts with the first feed pipe, enters the end of the first reactor, and enters the first reaction zone outlet oil distributor. The oil gas and low-temperature low-activity catalyst / low-temperature solid heat carrier are distributed and preliminarily separated. The regenerated catalyst / solid heat carrier from the second regeneration inclined pipe is transported to the regenerated catalyst / solid heat carrier catalyst distributor for distribution, mixed with C4 and / or light gasoline through the second feed pipe and the oil gas and part of the low-temperature catalyst separated by the first reaction zone outlet oil distributor, and another part of the low-temperature catalyst is transported to the second reaction zone through the outer annular cavity of the sleeve by the outer first fluidized ring of the sleeve, and the oil gas is deeply cracked in the second reaction zone. The oil gas passes through the second reaction zone and enters the rear transport pipe, and the oil gas and the catalyst are separated by the separator, the oil gas enters the rear separation system, and the catalyst is collected to the stripping section and transported to the regenerator for regeneration by the spent inclined pipe.

[0091] Comparative Example

[0092] The existing catalytic cracking process is used, that is, a reaction technology in which a riser and a fluidized bed are connected in series is adopted.

[0093] The reaction conditions and product distribution of the comparative example and the examples are compared in Table 1.

[0094] Table 1 Comparison of reaction conditions and product distribution of comparative example and examples

[0095]

[0096] As can be seen from the data in the table, the propylene yield and selectivity are greatly increased, and the dry gas and coke yields are greatly reduced. Compared with Example 2, Example 1 has an additional riser reactor in the third reaction zone, and the propylene yield and selectivity of Example 1 are higher.

[0097] In the present application, the terms "first", "second", "third" are used only for the purpose of description, and cannot be understood as indicating or implying relative importance; the term "a plurality of" refers to two or more, unless otherwise explicitly limited. The terms "mounting", "connecting", "connecting", "fixing" and the like should be understood in a broad sense, for example, "connecting" can be fixed connection, can also be detachable connection, or integral connection; "connecting" can be direct connection, or indirect connection through intermediate medium. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0098] In the description of the application, it should be understood that the terms "upper", "lower", "left", "right", "front", "rear", and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the purpose of facilitating the description of the application and simplifying the description, and do not indicate or imply that the device or unit referred to must have a particular direction, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the application.

[0099] In the description of the present application, the description of the terms "one embodiment", "some embodiments", "a specific embodiment" and the like means that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present application. In the present application, the illustrative description of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0100] The above is only the preferred embodiment of the present application, and is not intended to limit the present application. The present application can have various modifications and changes for those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principles of the present application shall be included in the protection scope of the present application.

Claims

1. A cracking device, characterized in that: include: a first reactor, wherein a first reaction zone is formed in the first reactor; a second reactor, wherein one end of the first reactor is located inside the second reactor, and a second reaction zone is formed in the second reactor; a sleeve, sleeved on one end of the first reactor located inside the second reactor, with a gap left between the outer wall of the sleeve and the second reactor; an oil distributor, disposed between the sleeve and the first reactor; The oil dispenser comprises: a distribution pipe, wherein a first through hole is formed on the distribution pipe; Wherein, there are multiple oil dispensers; The first reactor includes: a fluidized bed reactor or a riser reactor; The second reactor is a dense phase fluidized bed; Also includes: A catalyst distributor is provided in the second reactor, and an output end of the catalyst distributor is provided toward the sleeve.

2. The cracking device according to claim 1, characterized in that Also includes: The riser is connected to one end of the first reactor which is away from the second reactor.

3. The cracking device according to claim 1, characterized in that Also includes: a first fluidizing ring, the fluidizing ring being provided with a second through hole, the first fluidizing ring being arranged in the second reactor and being located between the sleeve and the second reactor; a second fluidizing ring, the fluidizing ring being provided with a third through hole, and the second fluidizing ring being arranged on an end of the first reactor close to the second reactor; A steam supply device is connected to the first fluidizing ring and the second fluidizing ring.

4. The cracking device according to any one of claims 1 to 3, characterized in that Also includes: a first feed pipe, connected to the first reactor; a delivery pipe connected to an end of the second reactor away from the first reactor; a stripping section, wherein the transfer pipe passes through the stripping section; a settler connected to the other end of the conveying pipe; a separator, disposed in the settler; The inclined pipe to be produced is connected to the stripping part.

5. The cracking device according to claim 4, characterized in that Also includes: A catalytic regeneration system is connected to the inclined tube to be regenerated; The first regeneration inclined tube is connected to the first reactor and the catalytic regeneration system.

6. The cracking device according to claim 1, characterized in that Also includes: a second regeneration inclined pipe, connected to the catalyst distributor; a second feed pipe, connected to the second reactor and located between the catalyst distributor and the first reactor; or a third reaction zone riser connected to the catalyst distributor; a third regeneration inclined tube connected to the third reaction zone riser; The third feed pipe is connected to the third reaction zone riser.

7. A cracking method, characterized in that: For use in a cracking device according to any one of claims 1 to 6, the cracking method comprises: By controlling the feed rate of the raw oil, the residence time of the raw oil in the first reaction zone is 1s to 2s, and the residence time of the oil and gas in the second reaction zone is 2s to 5s; The reaction temperature of the first reaction zone is 550°C to 600°C, and the reaction temperature of the second reaction zone is 630°C to 730°C.

Images