JPH0386230A - Two-stage fluid catalytic action cracker and its manufacture - Google Patents

Abstract

PURPOSE: To improve a feedstock treatment capability by adding an upper reaction chamber as a second step regeneration chamber, a removing chamber as an external catalyst heat removing region, a hydrocarbon supplying means and a lateral reaction chamber to a conventional system. CONSTITUTION: A catalyst take-out passage 90 which takes out catalyst is added via a catalyst collecting means 86 and is provided with a regenerated gas take-out means 88. The upper reaction chamber 12 is functioned as the second step regeneration chamber. A means 94 for depriving the heat from the removing chamber 14 and a means 102 for distributing the fluidized gas into the chamber 14 are disposed and are functioned as the external catalyst heat removing region. Further, the supplying means for the hydrocarbon which is the feedstock is exchanged with means 18' for supplying the ascending gas into an external passage 20. The lateral reaction chamber 64 having an ascending passage 70 for taking the regenerate catalyst from the catalyst take-out passage 90 and a removing chamber 76 for supplying the spent catalyst to a means 80 for adding the spent catalyst to a lower regeneration chamber 10 is added to the flowable catalyst cracking device of a stacking system.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention This invention relates to a two-stage fluid catalytic cracker and a method of manufacturing the same. This invention relates to converting heavy hydrocarbons into light hydrocarbons (hereinafter referred to as FCC) using a fluidized stream of catalyst particles. In particular, the invention relates to an apparatus for implementing the FCC method.

Prior Art To perform catalytic cracking, hydrocarbons in a reaction zone are contacted with a finely divided catalyst. Unlike hydrogen cracking, in catalytic cracking, a significant amount of coke is deposited on the catalyst as the zero cracking reaction proceeds, in which the reaction occurs without adding or consuming hydrogen. The coke on the catalyst is burned by high-temperature regeneration. The coke-containing catalyst is referred to herein as spent catalyst; the spent catalyst is continuously removed from the reaction zone and replaced with substantially coke-free catalyst from the regeneration zone. Hydrocarbon Decomposition in a Fluid Catalyst Stream 1 Transfer of the catalyst between the reaction zone and the regeneration zone; One method of carrying out such as combustion of coke in a regeneration chamber is well known to those skilled in the art of FCC processing. A number of chamber configurations are known in the art for use in contacting the catalyst particles with the feedstock or regeneration gas in the processes described above.

A well-known structure of an FCC device that was widely recognized from the 1950s to the 1960s is a stacked FCC reaction regeneration device. This conventional device has a reaction chamber stacked above a regeneration chamber. Regenerated catalyst from the regeneration chamber flows through the regeneration chamber distribution pipe into the riser passage and contacts the FCC feedstock. The catalyst and reaction feed vapor are separated by a cyclone in the reaction chamber where expanded gases originating from the feedstock and fluidized medium carry the catalyst upwardly in the external riser passage and into the reaction chamber. The feed vapor is discharged to an upper recovery passage, while the catalyst collects at the bottom of the reaction chamber.A removal chamber depending from the side of the reaction chamber receives spent catalyst from the reaction zone. An updraft from the bottom of the removal chamber opposes the descending catalyst flow to remove adsorbed hydrocarbons from the catalyst. The spent catalyst from the removal chamber continues down through the reaction chamber distribution pipe and into the dense fluid catalyst bed in the regeneration chamber. The coke on the spent catalyst reacts with oxygen in the air stream rising in the regeneration chamber and ultimately becomes regeneration gas. A cyclone at the top of the regeneration chamber also returns catalyst particles to the rich catalyst bed so that relatively catalyst-poor regeneration gas is discharged from the upper gas passage.

Changes in regeneration technology, available feedstocks, and demands for higher yields have significantly reduced the utility of the T11 stacking system. In stacked FCC devices, it is useful to add two additional techniques to the regeneration technique: multi-stage regeneration and a means to remove heat from the regeneration chamber. The changes described above have been driven by the desire to improve the conversion of a wide variety of feedstocks.

Typically, coke must be almost completely removed from the catalyst in order to achieve optimal 12 feedstock conversion; this substantially complete removal of coke from the catalyst is often referred to as complete regeneration. Complete regeneration produces a catalyst with less than 0.1% by weight coke, preferably less than 0.05% by weight. For complete regeneration, more than the stoichiometric amount of oxygen required to burn the coke to carbon oxides is supplied to the regeneration chamber. Excess oxygen in the regeneration zone also reacts with carbon monoxide produced by the combustion of coke to generate further heat. When a single regeneration chamber is used, there is relatively little catalyst in the regeneration chamber, such as in the region above the rich catalyst bed, and if CO combustion occurs in such regions of the regeneration chamber, the high temperature Related parts are severely damaged. On the other hand, if CO combustion occurs within the catalyst as a heat dissipating agent, the above situation can be avoided.

Therefore, the regeneration chamber is usually constructed such that oxygen and carbon monoxide do not come together in areas where there is relatively little catalyst. Nevertheless, the unexpected heat generated by CO combustion can have process effects such as increasing the temperature of the catalyst, thermally deactivating it, or limiting the amount of catalyst that can contact the feedstock. Occurs. When applying FCC processing to heavy feedstocks, the above-mentioned problems of controlling catalyst temperature and regeneration chamber temperature become more serious.Since coke generation tends to increase with heavy residual feedstocks, coke and CO combustion Due to the excessive heat generated, complete regeneration of the catalyst becomes increasingly difficult. A common method that can obtain sufficient regenerated catalyst while minimizing CO combustion is a multi-stage regeneration method.

Even apart from minimizing CO combustion, the increase in coke on the catalyst reduces the amount of recycled catalyst to about 45:1 g (
1 bond), the amount of coke burned in the regeneration chamber increases. The heat removed from the regeneration chamber of a conventional FCC device becomes the flue gas and primarily the high temperature regenerated catalyst stream. When the amount of coke on the spent catalyst is large, the temperature difference between one reaction chamber and the regeneration chamber becomes large, and the temperature of the regenerated catalyst increases as a whole. Therefore, in order to maintain the same reaction chamber temperature, it is necessary to reduce the amount of circulating catalyst. However, low catalyst circulation in response to a large temperature difference between the reaction chamber and the regeneration chamber reduces hydrocarbon conversion, requiring a high operating temperature in the reaction chamber to maintain the desired conversion level. It will stop happening.

Under the above circumstances, there is a limit to the temperature that an FCC catalyst can tolerate without causing unintended structural changes in the raw material structure depending on the type of processed product, and without having a substantial negative effect on catalyst activation. be. Generally, using the latest commonly available FCC catalysts, approximately 760-790°C (
The temperature of the regenerated catalyst is typically 760°C (below +400°C) since the activation loss is very significant between 1400 and +450'F.
kept below.

Light Arabian Cru
When a relatively numerically reduced feedstock, such as extracted from de oil, is fed to a conventional FCC unit and processed at the temperatures necessary to convert it to a lighter product, such as a gas oil feedstock, the regeneration chamber temperature is 870-980℃ (1600-180℃
(below 0). This temperature is not only too high for the catalyst, but also requires very expensive construction materials and also greatly reduces the circulation rate of the catalyst. Therefore, by removing heat from the regeneration chamber when processing raw materials that cause the regeneration chamber temperature to become excessive, the regeneration chamber temperature can be lowered and the temperature difference between the reaction chamber and the regeneration chamber can be reduced.

In the regeneration of FFC catalysts, multi-stage regeneration systems are well known. U.S. Pat. No. 3,958,953 discloses a multi-stage apparatus having concentric catalyst beds separated by panflues opening into a common space to collect spent regeneration gas and separating catalyst particles. Mayer et al. U.S. Patent No. 4.2
No. 99.687 discloses the use of a multi-stage regenerator with stacked catalyst beds in which the spent catalyst particles first enter an upper thick fluidized catalyst bed and are contacted with regeneration gas from the lower catalyst bed and fresh regeneration gas. Disclosed. After partial regeneration in the first regeneration zone, the catalyst particles are forced downward into the lower catalyst bed where a fresh regeneration gas stream is supplied. Maier's invention processes residual feedstock and uses a two-stage regeneration process to limit CO combustion and reduce overall heat production within the regeneration chamber.

U.S. Pat. Nos. 3,844,973 and 3,923,606 to Steinka demonstrate complete catalyst regeneration through the use of a relatively dilute phase regeneration zone. Stein's invention originally aimed to perform complete CO combustion from the viewpoint of reducing air pollution, increasing thermal efficiency, and downsizing the device, using a high-velocity gas, a dense catalyst bed, and a relatively dilute phase regeneration region. Moving the catalyst.

U.S. Pat. No. 4,336,103 to Dean et al. shows a two-stage system that combines a relatively dilute phase regeneration zone and a rich catalyst bed zone to regenerate catalyst for residual feed cracking. Dean's invention uses the 1m catalyst bed to initiate coke combustion in the lower regenerator and operates the upper diluted phase regenerator following the lower regenerator severely to achieve regeneration and carbon monoxide combustion. Achieved. Dean's invention uses a modified stacked FCC device, in which a stacked regeneration chamber is used as the concentrated catalyst regeneration section, but the dilute phase regeneration is attached to the side of the stacked device. It is supposed to be done indoors.

Conventionally, a common means for removing heat from the regeneration chamber is to include a refrigerant-filled coil in the regeneration chamber in contact with the catalyst.
No. 1, U.S. Pat. No. 3,990,992 to MacKinney, and U.S. Pat. No. 4,219,442 to Piggers disclose an FCC method using a dual zone regeneration chamber with a cooling coil in the second zone. There is. Additionally, there are a number of prior art techniques demonstrating FCC processing, which involve cooling and regenerating the hot regenerated catalyst using a heat exchanger that is located outside the regeneration chamber to remove heat from the rich or dilute phase regenerated flowable catalyst. For example, U.S. Patent No. 4,439 for Lomasization
In the external heat removal zone described in No. 533, catalyst is circulated between the heat removal zone and the regeneration chamber via a single passage communicating with the regeneration chamber.

Problems to be Solved by the Invention Normally, a stacked type FCC device is structured to operate with only one stage regeneration, and is not equipped with an external means to remove heat from the catalyst. Significant 1 for this type of equipment that cannot accommodate catalytic heat removal
2 The need for changes has been recognized, and the existing stacking type FC
Furthermore, when one-stage regeneration is performed in partial CO combustion mode, a stacked FCC device is commonly used.Normally, the structure of the regeneration chamber for partial CO combustion operation is not suitable for complete CO regeneration. Many FCC devices in operation today require higher quality components that are not suitable for the high temperatures associated with regeneration, which reduces device availability.

Many stackable devices have been modified to accommodate high operating temperatures. - Numerical improvements include replacing internal components with more heat resistant components and using internal insulation or external convection devices to reduce the skin temperature of metal components such as passages or chamber walls. From this point of view, conventional reaction chamber metal materials are generally not compatible with reaction chambers where high temperatures are desired.

If the reaction chamber temperature is limited, the conversion action is also limited, so it is highly desirable to replace the reaction chamber of the apparatus.

SUMMARY OF THE INVENTION According to the method of the present invention, many of the existing components used in stacked FCC devices are used as part of a new stacked FCC device with two-stage regeneration, and an external heat removal section is added. Attach. This greatly increases the throughput of conventional stacked FCC equipment and allows the processing of heavier feedstocks to be performed at lower cost. Utilizing existing reaction chambers, regeneration chambers, and removal chambers results in cost reductions.

According to the method of the present invention, a stacked FCC unit is converted into a regenerator with at least two stage regeneration for use as part of a large scale flowing FCC process. The simplest modification uses the conventional regeneration chamber as the first stage regeneration zone, the conventional reaction chamber as the second stage regeneration zone, and the conventional reaction chamber and removal chamber as the catalytic heat removal zone.

Accordingly, one embodiment of the invention includes a lower regeneration chamber, an adjacent upper reaction chamber, an external passageway for removing catalyst from the lower part of the lower regeneration chamber and conveying it to the upper reaction chamber, and a means for adding spent catalyst; means for recovering regeneration gas from an upper portion of the lower regeneration chamber; and a removal chamber that is laterally offset from the upper reaction chamber and opens and communicates with the reaction chamber. The stacked FCC reaction regenerator will be changed to a two-stage regenerator.

In this modification method, a means for collecting the catalyst is added to the lower part of the upper reaction chamber, and a means for taking out the regeneration gas from the upper end of the upper reaction chamber is provided, so that the upper reaction chamber functions as a second stage regeneration chamber. Change it as follows. The catalyst collection means communicates with a catalyst removal passage for taking out the catalyst from the upper reaction chamber. It also includes a heat exchanger for extracting heat from the side chambers and means for distributing fluidizing gas to the side chambers. This causes the conventional removal chamber to function as an external catalytic heat removal area. If necessary, change the external catalyst passage to use it as a rising gas supply section.

The modification method and device operation according to the present invention are not limited to the above.

According to another embodiment of the invention, the external passageway for conveying the catalyst from the lower regeneration chamber to the upper reaction chamber serves as a region for further regeneration.

Example Hereinafter, this invention will be explained in detail with reference to Examples.

The method of the present invention includes steps for modifying the functionality of conventional stacked FCC devices.

An apparatus to which the method of the present invention can be applied has an upper reaction chamber stacked above the lower regeneration chamber, and a removal chamber that hangs down from the upper reaction chamber and communicates with the upper reaction chamber. Since the modified method of this invention can be implemented by adding an additional reaction chamber to the side of the conventional stacked system, the feedstock throughput of the modified FCC system will generally be increased. Therefore, the present invention can be applied to any stacking type device in which a new reaction chamber can be added.

FIG. 1 shows a stacked FCC device to which the method of the present invention can be applied. As shown in FIG. 1, the conventional FCC device includes a lower regeneration chamber 10, an upper reaction chamber 12, and a side removal chamber 14. have. The catalyst from the lower regeneration chamber 10 passes within the regenerated catalyst passage 16 and enters the rising external passage 20 via the control valve 23 . In this external passage 20, a fluidizing medium, such as steam, can be added to the feed in the 0 passage la, where the regenerated catalyst contacts the hydrocarbon feed from the hydrocarbon feed passage 18. Expandable gas generated from the feed and fluidizing medium carries the catalyst upwardly in the outer passage 20 and into the rising inner passage 22 as the catalyst and feed are rising in the rising passage. , the feedstock hydrocarbons are cracked into low-boiling hydrocarbon products.

Through outlet 44 the catalyst and hydrocarbon mixture enters internal passage 2.
2, an initial separation of catalyst vapor and hydrocarbon vapor takes place. Outside the outlet 44, most of the hydrocarbon vapors continue to move upwards into a cyclone 46 which almost completely removes the catalyst from the hydrocarbon vapors.The separated hydrocarbon vapors pass through the top passage. 48
is discharged from the upper reaction chamber 12 via the upper reaction chamber 12, while the separated catalyst returns to the lower part of the upper reaction chamber 12 through the depending leg passage 50. Catalyst from the outlet 44 of the internal passage 22 and the depending leg passage 50 collects in the lower portion of the upper reaction chamber 12 to form a catalyst bed 52. On the other hand, from the passage 54 to the removal chamber 14
The steam supplied to the removal chamber 14 becomes an upward flow that opposes the downward flow of catalyst in the removal chamber 14 to remove adsorbed hydrocarbons from the catalyst. The removed hydrocarbons are finally recovered by the airflow from the cyclone 46. A series of downwardly sloped buttles 56 are provided within the removal chamber 14 to facilitate removal of the hydrocarbons. Lower conical section 6 of removal chamber 14
Catalyst from 0 is removed by a spent catalyst passage 58. Catalyst flow through the 0 passage 58 is regulated by a control valve 59.

Regeneration gas, such as compressed air, enters the lower regeneration chamber 10 via passageway 30. The air distributor 28 distributes air across the cross section of the lower regeneration chamber 10 and the dispersed air contacts the spent catalyst bed 34 with oxygen from the distributor 28 to cause combustion and remove coke from the catalyst. Combustion by-products and unreacted air components, together with the entrained catalyst, rise within the lower regeneration chamber 10 and enter the cyclone 26. Gas almost free of catalyst components collects in an internal chamber 38 inside the lower regeneration chamber 10. This internal chamber 38 communicates with a gas passage 40 for removing spent regeneration gas from the lower regeneration chamber 10. The catalyst separated in the cyclone 26 is
, and returns to the catalyst bed 34 through the depending leg passages 42 .

The temperature of the catalyst and hydrocarbon mixture entering reaction chamber 12 via outlet 44 is typically below 540°C. Therefore, the peripheral wall 6 of the reaction chamber 12 and the removal chamber 14
2 is usually made from carbon steel or low chromium material without backing. Also, a cyclone 46, an internal passage 22, a baffle 56
The internal components of reaction chamber 12 and removal chamber 14 are also made from similar metal materials. Therefore, the reaction chamber 12, the removal chamber 14, and their internal equipment are typically heated to 540°C (100°C).
Reaction chamber 12 and removal chamber 14 cannot be used for second stage regeneration conducted at temperatures above 0''F), i.e. unless modified to withstand higher temperatures, reaction chamber 12 and removal chamber 14 are
It is not suitable for second stage regeneration in the staged regeneration method.

On the other hand, the peripheral wall 24 of the lower regeneration chamber 10 is usually made of a metal material lined with firebrick and has a temperature of 815°C (tso).

(lower) and above internal temperatures. The lower regeneration chamber 10 itself is therefore adapted to high operating temperatures. However, the cyclone 2, which is the main device inside the lower regeneration chamber 10,
6 and air distributor 28 are not compatible with high temperature operation, so it is preferable to use a new interposed regeneration device in the first stage of the two-stage regeneration method.

FIG. 2 shows an FCC apparatus of the invention, in which a modification of the stacking apparatus of FIG. 1 forms part of the two-stage regeneration system of the apparatus of FIG. The two-stage regenerator includes upper reaction chamber 1
2 and 0 reaction chamber 64, which has a reaction chamber 64 located near the side of the lower regeneration chamber 10, is adapted to carry out the ascending decomposition action well known to those skilled in the art. In operation, the regenerated catalyst enters the Y-section 66 and contacts the feedstock hydrocarbons supplied from pipeline 68. Optionally, the fluidizing medium is also supplied via a pipeline. The expanded hydrocarbon vapor and the fluidizing medium therefore carry the catalyst upwardly in the outer passage 70 and into the inner passage 7z.

Similar to the steam associated with upper reaction chamber 12 , catalyst and hydrocarbon vapors are separated by the outlet of internal passage 72 and a pair of cyclones 74 , and the hydrocarbon vapors are passed through upper steam passage 75 to reaction chamber 64 . while the catalyst is returned to the bottom of the reaction chamber 64. The catalyst at the bottom of the reaction chamber 64 is returned to the removal chamber 7 against the air flow entering through the distributor 78.
Descend downward within 6.

At the bottom of the removal chamber 76 the catalyst contains 0.05-2.0% by weight of coke and is returned to the regeneration chamber via the regeneration catalyst passage 80.

Traditionally, the cyclone 26 and air distributor 28, which have been made of ordinary low-chromium metals, have a temperature limit of approximately 650°C (1200"F), but can withstand temperatures up to 790°C (1450"F). Change to stainless steel.

The provision of the reaction chamber 64 along with the attached equipment changes the functions of the upper reaction chamber 12 and the removal chamber 14, so if the above-mentioned chambers and the rest of the stacked regenerator are changed according to the present invention, the regeneration capacity and flexibility can be increased. You can increase your sexuality. Adding reaction chambers and modifying existing chambers can increase feed capacity by approximately 20-60% for typical stacked devices.

In the modified stacked regenerator shown in FIG. 2, when first changing the regeneration chamber, a passage 80 is provided for conveying the spent catalyst from the reaction chamber 64 to the lower regeneration chamber 10. In the one in FIG. 2, an inlet nozzle 82 is newly installed on the side of the lower regeneration chamber 10.
is provided so that the passageway 80 communicates with the interior of the lower regeneration chamber 10. Since the nozzle 32 is still being used to convey catalyst from the side removal chamber 14 to the lower regeneration chamber 10, a new nozzle 82 must be provided. The lower regeneration chamber 10, except for the attached nozzle 82, serves as a first stage regeneration zone with a rich catalyst bed 34.

Regeneration chamber 10 operates in substantially the same manner as described above.

Preferably, the first stage regeneration is operated in partial CO combustion mode. In this mode of operation, approximately 50-90% of the coke on the incoming spent catalyst is removed by first stage regeneration. To lower operating temperatures and oxygen requirements, the first stage regeneration involves only partial oxidation of the carbon monoxide generated during coke combustion. This mode of operation has lower temperatures and requires less air supply, making it easier to use existing equipment as a regeneration chamber. cyclone 26
In the case of the regeneration chamber 10 in which the air distributor 28 is made of a low-alloy metal material, the temperature of the lower regeneration chamber 10 is, for example, 650°C.
If it is as low as 1200 or lower, the operating life of the metal material will be extended. In addition, since the air flow rate set in the air distributor 28 is quite low, it is not possible to supply all the amount of oxygen required to burn all the coke and carbon monoxide in the lower regeneration chamber 10. Since the staged regeneration zone uses only 30-70% of the air required for complete combustion of coke and CO, the air distributor 28 can be adapted for first stage regeneration without substantial modification.

Even in the device shown in FIG. 2, the catalyst is regenerated through the catalyst passage at a rate determined by the control valve 23! It leads to 6. However, in this device, the catalyst entering the external passage 20 is only partially regenerated.The air supplied from the zero passage 1g' contacts the partially regenerated catalyst at the bottom of the external passage zO, and the catalyst particles In this way, the external passage 2
o functions as an area for further reproduction. The air also acts as a rising gas, carrying the catalyst particles upwards in the external passage 2o and supplying them to the bottom of the upper reaction chamber 12.
An air distributor is provided which directs air from the air into the external passageway 20, which distributes from the simple open vibrator 21 shown in FIG. For very large ascending passages, a distributor with multiple outlets spaced over the inner diameter of the outer passage 20 can be used. Since the temperature of the regenerated catalyst is typically as low or lower than the temperature of the catalyst entering this region in the prior art system prior to modification, existing components can be adapted and used in the two-stage system. The upper portion of the outer passage 20 has a higher operating temperature than the lower portion as the coke and coke by-products continue to burn as the catalyst moves upwardly within the riser passage. This temperature situation is opposite to that when the upper chamber 12 is used as a reaction chamber and the temperature decreases as the catalyst rises. Therefore, the upper portion of the existing external passage 20 is not compatible with the high temperatures (typically above 650° C. (below 1200° C.)) associated with complete regeneration of the catalyst.

Therefore, the upper portion of the external passage 20 must be replaced with a high metal material such as stainless steel or with a pipe member with internal thermal insulation. Apart from this, the temperature of the metal material in the external passage zO can be lowered by removing the internal insulation and convectively cooling the pipe surface. Although it is slight, the convection cooling has the effect of removing heat from the catalyst and lowering the overall catalyst temperature in the upper reaction chamber lz,
This reduces the amount of cooling required for the catalyst.

The upper reaction chamber 12 serves as a discharge chamber and, to the extent necessary, as a second stage combustion zone, where unconverted coke and coke by-products enter the upper reaction chamber 12 containing the catalyst from the external passage 20. A dense catalyst bed 84 is formed within the upper reaction chamber 12, the chamber 12 serving as a combustion zone;
The catalyst from the external passage 2o flows into this. Concentrated catalyst bed 8
4 is at the same level as or higher than the internal hopper 86. Since internal passage 22 has been removed, hopper 8
This allows space for 6 to be secured. spent regeneration gas;
The entrained catalyst moves upwardly from catalyst bed 84 and into cyclone 46'. Gas is separated from the catalyst in this cyclone 46' and recovered by an upper passage 88, while catalyst particles are returned to the catalyst bed 84. The used regeneration gas used for complete regeneration in the upper reaction chamber 12 is 1
Due to the high temperatures associated with full regeneration, including ~2% excess oxygen, cyclone 46 is replaced with a new cyclone 46' made of stainless steel. The fully regenerated catalyst particles from the catalyst bed 84 are collected in a hopper 86, leave the upper reaction chamber 12, and pass through the regenerated catalyst passageway 90 to the wye section 6.
Sent to 6.

In the embodiment of FIG. 2, catalyst from catalyst bed 84 is also pumped into removal chamber 14. This catalyst is removed from the bottom of the removal chamber 14 and fed into the lower regeneration chamber 10 via a passage 58 which serves as a cooling passage. The removal chamber 14 is a cooling layer! 94 and inserting a heat exchange tube 96. The heat exchange tube 96 is of a bayonet type. The cooling fluid, typically water or a saturated air stream, is supplied to the distribution head 98 and then distributed to the bayonet tubes. The cooling fluid that has exited the bayonet tube is collected in the chamber 10G and then discharged to the outside.

When the catalyst contacts cooling tube 96, lower regenerator 10 also removes heat, creating a relatively cool source of catalyst. The cooling system operates in a downflow mode and directs relatively cool catalyst particles through passageway 58 to the first stage regeneration region of lower regeneration chamber 10. The cooling system can also be operated in a backmix mode to circulate catalyst between tubes 96 and crushed catalyst bed 84.

The fluidizing gas is typically air, which is supplied via distributor 102 to a location below tube 96 in removal chamber 14.
Fluidized media flow into distributor 102.

control valve 104). The amount of fluidizing medium introduced is small to facilitate the flow of the catalyst through the cooling device.
and to ensure that the catalyst is well distributed around the tubes 96. When the downward flow of catalyst in removal chamber 14 is shut off by control valve S9, the amount of air increases, increasing the amount of catalyst backmixed through distributor 102 with rich catalyst bed 84. The rest of the operation of the catalyst cooling system is the same as in the previously mentioned references.

According to another slightly simpler embodiment, the removal chamber 14 accommodates a catalyst cooling device that operates only in the back-mixing mode. In this embodiment, as shown in FIG. 3, the lower portion of the removal chamber 14 is closed by a chamber 100' and a dispensing head 98'. In FIG. 3, heat exchange tubes 96' extend upwardly from chamber 100' and distribution head 98'. Fluidization gas is delivered to removal chamber 14 via distributor 102' near chamber 100'.
supplied to

In this embodiment mode of operation, heat transfer and catalyst exchange with catalyst bed 84 is completely controlled by the fluidizing gas provided by distributor 102'. Although this device allows only the cooled catalyst particles to participate in the second stage regeneration, the device operation can be made simpler by eliminating the control valve and catalyst transport passage. In addition, in this embodiment, nozzle 3
2 can be used to receive the spent catalyst from the reaction chamber 64.

Although the invention has been described in detail, the scope of the invention is not limited by the embodiments described above, and in particular examples have been described that utilize various existing components such as cyclones, air distributors, and catalyst passages. The present invention can be applied as long as specific members other than the regeneration chamber, reaction chamber, and removal chamber are changed.

[Brief explanation of drawings]

Figure 1 is a front view showing a conventional stacking type FCC device, Figure 2
The figure is a front view of an embodiment of the invention, and FIG. 3 is a front view of main parts of another embodiment of the invention. 10...Lower regeneration chamber 12...Upper reaction chamber 14
...Removal chamber 18...Hydrocarbon supply means 1
g'... Rising gas supply means 20... External passage 40... Regeneration gas recovery means 48... Hydrocarbon vapor extraction means 58... Addition means 64... Side reaction chamber 70
... Rising passage 76 ... Removal chamber 80 ... Addition means 86 ... Collection means 88 ... Regeneration gas extraction means

Claims (1)

[Claims] 1. A lower regeneration chamber 10, an adjacent upper reaction chamber 12, an external passage 20 for taking out the catalyst from the lower part of the lower regeneration chamber 10 and feeding it into the upper reaction chamber 12;
means 18 for feeding hydrocarbon feed into the lower regeneration chamber 10; means 58 for adding spent catalyst to the lower regeneration chamber 10; and means 40 for recovering regeneration gas from the upper part of the lower regeneration chamber 10.
a stacked flow system comprising: a means for extracting hydrocarbon vapors from the upper portion of the upper reaction chamber 12; and a removal chamber 14 which is laterally offset from the upper reaction chamber 12 and opens into and communicates with the reaction chamber. 1. A method of manufacturing a two-stage fluid catalytic cracker by modifying a fluid catalytic cracker by: (a) adding means 86 for collecting catalyst in the lower part of the upper reaction chamber 12; A catalyst removal passage 90 is added which communicates with the lower part of the upper reaction chamber 12 and takes out the catalyst from the upper reaction chamber 12.
Means 8 for taking out the regeneration gas from the upper end of the upper reaction chamber 12
(b) means 94 for removing heat from the removal chamber 14 and fluidizing gas within the removal chamber 14; (c) modifying the removal chamber 14 to function as an external catalytic heat removal zone by providing means 102 for distributing the rising gas into an external passageway; (d) removing the spent catalyst by supplying it to the rising passage 70 which takes in the regenerated catalyst from the catalyst removal passage 90 and the means 80 which adds the spent catalyst to the lower regeneration chamber 10; adding a side reaction chamber 64 having a chamber 76 to the stacked fluid catalytic cracker. 2. A method for manufacturing a two-stage fluid catalytic cracking device according to claim 1, wherein in step (c), the spent catalyst addition means 58 is used as a cooling passage for sending the catalyst from the removal chamber 14 to the lower regeneration chamber 10. . 3. The method of manufacturing a two-stage fluid catalytic cracker according to claim 1, wherein step (c) includes adding means for cooling the catalyst along the external passageway (20). 4. The method of manufacturing a two-stage fluid catalytic cracker according to claim 1, wherein the means for removing heat in step (b) is a plurality of bayonet type heat exchange tubes 96 or a rear mixing cooling device 96'. 5. A rising device for fluid catalytic cracking having a two-stage cracking device manufactured according to any one of claims 1 to 4. 6. A method of converting a hydrocarbon stream as a feedstock in a reaction zone using a fluid catalyst, in which the spent catalyst is removed from the reaction zone and continuously regenerated in a fluid catalyst regeneration zone, In the conversion method, the conversion zone and the regeneration zone constitute a stacked reaction regeneration apparatus according to claim 1, wherein the stacked apparatus is converted into a two-stage fluid catalyst according to the process according to any one of claims 1 to 4. A method of changing to a fluid catalytic cracking lift device with a cracking catalyst regenerator.