JPS63165484A - Method and apparatus for catalytic cracking of hydrocarbon charge raw material in reaction zone through which extremely inert solid particle and catalyst particle flow - Google Patents

Abstract

According to the process, the feedstock and a first mixture of a major part of substantially inert solid particles originating from the line (4) are introduced into a vaporisation zone (1a) at a temperature T'2 of between 650 DEG C and 1200 DEG C, the feedstock and the first mixture of solid particles are caused to flow into a stream of carrier gas and a second stage of a major part of catalyst particles of smaller particle size and lower density originating from the line (6) is introduced into a cracking zone (1b) continuous with the vaporisation zone, at a temperature T'1 of between 300 and 750 DEG C, lower than T'2; the resulting mixture is circulated countercurrentwise in the cracking zone (1b), the cracking effluents and the solid and catalyst particles are recovered (9), the said effluents are separated from the said particles, the said particles are separated off (13a) and regenerated, an inert solid particle fraction and a catalyst particle fraction are recovered separately and are recycled into the vaporisation zone and into the cracking zone respectively. Application in the oil industry. <IMAGE>

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a method for catalytic cracking of hydrocarbon feedstocks containing residual substances in a reaction zone through which solid particles and catalyst particles used for pretreatment flow, and a method for carrying out this method. This relates to equipment for and its use.

BACKGROUND OF THE INVENTION The vaporization of heavy feedstocks, commonly referred to as residues (e.g., atmospheric distillation residues, vacuum distillation residues, deasphalted oils, coal liquefaction oils, shale oils, etc.), is commonly used by petroleum producers for catalytic cracking. The process requires modification of the purification equipment and pre-treatment aimed at removing as much as possible residual substances such as catalyst poisons, such as coke, sulfur and metals.

The raw material to be treated is 6-8% by weight of Conradson.
The maximum content of carbon (OCR) and metals of 20-3°pp. is sufficient to allow for the application of FCC (Fluidized Bed Catalytic Cracking) type processes.

On the other hand, if this feedstock is heavier (e.g. CC 110%), especially if the nickel and vanadium content reaches several hundred ppm, then the performance of the catalysts currently available on the market should be taken into account. This proves that pretreatment is necessary.

Prior Art and Problems There are several pre-processing techniques. These are, inter alia, delayed coking, liquid coking, hydrotreating, deasphalting, etc.

The prior art is described in particular in the documents listed below.

- European patent EP 127,285 vaporizes the feedstock by contacting it with a conventional cracking catalyst in the upstream part of the reaction column, and in order to increase the octane number of the gasoline obtained with the conventional catalyst, lower It concerns a cracking method in which a small amount of another catalytic zeolite ZsM5 is introduced into the downstream section at temperature.

- U.S. Patent No. 3,380,911 partially vaporizes and partially vaporizes the feedstock by contacting it at low temperatures with highly active, very small catalyst particles at the base of the reaction column. It describes a cracking method for converting . The remaining feedstock is subsequently vaporized and converted at higher temperatures by weakly active, large-sized catalyst particles in the downstream section.

- In US Pat. No. 4,243,514, pretreatment is carried out in a vessel provided for the purpose of vaporizing the feedstock by mixing it with preheated inert solid particles. known to do.

The particles are between 20 and 50 microns (20-150
x10-"m) and are produced, for example, directly by injection of viscous mud in a heat exchanger. The obtained spherules are characterized by their low specific surface area, which is However, it makes it possible to capture 95% of the metals and all of the asphalt, which is initially abundant in the feedstock. , fluidized bed catalytic cracking (F
The free effluent, which constitutes a sufficient charge for CC), must be separated from the catalytic cracking zone and cooled before being directed to a separate catalytic cracking zone.

In the catalytic cracking zone, pretreatment was carried out in order to reduce the risk of thermal cracking, which is inevitable due to the long process and the resulting considerable residence time at higher temperatures. As a result of the conversion, coke formation was encouraged.

It is therefore an object of the present invention to pretreat a hydrocarbon feedstock by placing it in contact with preheated solid particles. This particularly ensures a more advanced demetalization and substantial removal of the latent coke contained in the feed, with a residence time that causes almost no thermal cracking.

In conventional cracking methods, in which the energy required to vaporize the feedstock is supplied by the catalyst itself, the maximum temperature allowed for the reheated catalyst is about 800°C. In particular, accelerated deactivation of the catalyst is observed when the catalyst is exposed to large amounts of water during its regeneration.

One of the objects of the present invention is to carry out a more intense thermal flashing of the feed without hindrance to heat-conducting particles that do not have any catalytic properties, especially for very asphalt-rich feeds. The advantage is that the temperature allowed for the heat-conducting solid particles can be increased to about 1200°C.

Another object of the present invention is to suppress the aging of the catalyst during the feed cracking process of removing heavier products, to reduce the deactivation of the catalyst and, as a result, to reduce the deactivation of the catalyst. The goal is to reduce consumption.

Therefore, in general, high catalyst/oil localization ratios in the vaporization zone due to misdistribution of the feedstock in the injection zone, localization of the vaporized feedstock above 550°C to 600°C for the catalyst. Temperature and the presence of inhomogeneities on the micron scale are factors that cause the appearance of significant amounts of residual coke.

Another object of the invention is therefore to ensure a uniform and uniform distribution of the vaporized feed within the cracking zone and to reduce the formation of residual coke.

Another object of the present invention is to obtain the best and most selective feedstock conversion to derive an increase in vaporizable fraction.

Furthermore, too much coke is produced during cracking of heavy feedstocks in the presence of catalyst alone. this is,
During regeneration of the catalyst, once it is oxidized, it produces an amount of energy that exceeds the energy demand of the process. Another object of the invention is therefore to adjust the amount of coke strictly necessary to the demands of the equipment (feed vaporization and cracking).

The term feedstock refers to conventional feedstocks, i.e. distillates with a final boiling point of around 400°C, such as gasoline by vacuum distillation, crude oil or non-gasoline, and residues of atmospheric or vacuum distillation. Imagine a heavier hydrocarbon oil. These raw materials, if necessary,
For example, it can be subjected to a pretreatment such as hydrotreating in the presence of cobalt-molybdenum or nickel-molybdenum type catalysts. Preferred feedstocks for the present invention contain a higher percentage of asphaltic material and generally a higher content of Conradson carbon (e.g. greater than 8%, more advantageously between 8 and 40%, preferably Between 10 and 25%', A
37M standard, see Te5t189-65).

These feedstocks include hydrocarbon fractions that have already been subjected to a cracking operation, such as light recycled oil (“li
ght cycle ol13”, L, C, O,) or recirculated heavy oil (“heavy cycle
According to the preferred method of the present invention, these feedstocks can be diluted or not with recycled conventional lighter fractions such as is 100 to 45 before its processing.
It is preheated in a temperature range lying between 0°C.

SUMMARY OF THE INVENTION In order to solve the above-mentioned disadvantages, the present invention provides a method for catalytic cracking of a hydrocarbon feed having a high Conradson carbon value and containing residual material in the reaction zone of a fluidized bed, comprising: The method is to introduce two types of particles of different sizes into two different levels of the reaction zone at different temperatures T-2 and T'. The first part of the reaction zone, called the vaporization zone, contains the bulk of the above-mentioned feedstock, carrier gas and very inert solid particles, and apart from this very inert solid particles a small amount of catalyst particles. The first mixture with the part is heated from 650°C to 120°C.
It is introduced at a temperature T'2 of between 0°C and preferably between 750°C and 1000°C.

The highly inert solid particles described above have a specific surface area of less than 50 m2/g, a cracking activity of at most about 15%, a
0 to 2000 microns (100-200X10-'
m) and particle size between 2000kg/m3 and 6000k
It has a density between g/m3.

The above catalyst particles have a cracking activity of 20% or more, 1
Particle size between 0 and 100 microns (10-100 x 10-6 m) and 600 kg/m3 to 1800 kg/m3
It has a density between m3.

Said first part of the reaction zone contains a first portion of said particles.
The mixture is flowed with the feedstock and carrier gas, preferably in co-current flow, to vaporize all the feedstock and remove at least a portion of the residual material under minimal silver cracking conditions.

From said first part, all the effluent of the first part of the reaction zone is introduced into a second part of said zone which follows said first part and is called the cracking zone.

At the same time, at the inlet of said second part, a second mixture of a large portion of catalyst particles as defined above and a small portion of highly inert solid particles is introduced. This second mixture is heated below the above temperature T″2 and between 300°C and 750°C, preferably between 500°C and 700°C, more preferably 50°C.
It is introduced at a temperature T'1 lying between 0°C and 650°C.

In said cracking zone, a mixture of all effluents from the first part of the reaction zone is cocurrently flowed with said second mixture of particles.

On the one hand, the cracking effluent is recovered, and on the other hand, the catalyst particles containing solid particles and at least a portion of the cracking residue are recovered. The cracking effluent is separated from solid particles and catalyst particles and collected. The solids and catalyst particles exiting the effluent separation step are subjected to at least one particle separation step and at least one fluidized bed regeneration step. A fraction containing most of the solid particles and a fraction containing most of the catalyst particles are collected separately.

The highly inert solid particles are recycled at least partially to the vaporization zone and the catalyst particles are recycled to the cracking zone of the reaction zone.

The catalyst particles are, of course, solid particles, but they are active particles. For convenience, they are referred to as catalyst particles or catalysts to distinguish them from highly inert solid particles.

The temperature of introduction of the catalyst particles, T-, is preferably at least 10 times lower than the temperature of introduction of the very inert solid particles, T-2.
℃low.

The process according to the invention offers the advantage of vaporizing the feedstock and removing impurities in a very short time with substantially reduced thermal cracking and thus favorable formation of coke. Therefore, during the feed vaporization step, the amount of coke deposited on the inert particles is less compared to the coke deposited on a conventional cracking catalyst under the same temperature conditions. The feedstock, which vaporizes upon contact with the solid particles, becomes acceptable to the catalytic cracking catalyst. This in fact advantageously removes, for example, at least 90% of residual substances and thus ensures a longer lifetime for the catalyst and a slower deactivation of the active sites upon regeneration of said catalyst. . Furthermore, this reduces catalyst and thermal cracking in the vaporization zone, avoids coke formation and ensures better conversion rates.

The presence of inhomogeneities within the vaporization zone is reduced and a uniform uniform distribution of the feedstock is ensured within the vaporization zone, through which the majority of highly inert solid particles flow. This reduces coke formation in the heat source. Furthermore, the conversion rate is better and more selective. This is because cracking strictly speaking takes place in a gaseous hydrocarbon atmosphere which is the donor of hydrogen.

In fact, the feed hydrocarbon vapor can be brought into contact with the catalyst in a catalytic cracking process at a temperature lower than that normally encountered.

This is because the catalyst brings only heat absorbed by cracking, which represents only about 10% to 20% of the heat of vaporization of the feedstock. This characteristic is
It makes it possible to reduce the amount of residual coke and cracking.

On the other hand, it is found that the lifetime of the catalyst is increased and its level of activity is maintained for a longer time.

According to a particular method of implementation of the invention, the vaporization (and pretreatment) zone has a length and an internal diameter, such that the L/D ratio is between 2 and 30, preferably between 5 and 15. , can be expressed.

This facilitates uniform distribution of the feedstock and complete vaporization of the feedstock before it reaches the cracking zone where the catalyst particles are fed. The distance separating the introduction of two populations of distinct particles is therefore dependent on the diameter of the reaction zone in which the vaporization of the feedstock takes place.

Preferred conditions of L/D vaporize all of the feed without substantial racking in the vaporization zone, depositing substantially all of the residual coke and metals on the solid particles;
We have reached a point where only the minimum amount of coke required for operation of a device based on this method is generated. The device is thus simplified. This is because the heat level is lower and the investment cost is also reduced.

Solid particles are distinguished from catalyst particles not only by their action, but especially by their size and density. This facilitates their subsequent separation.

In fact, the solid particles used for pretreatment are generally prepared by a method called BET using nitrogen absorption with nJ constant t, 50 f
It exhibits a specific surface area of f12/g or less, for example between 0.01 and 50a+2/g, preferably between 0.01 and 20 m2/g: more preferably between 0.01 m2/g and 10 m2/g. This helps to reduce thermal cracking of the feedstock. This is 100 to 20
Between 00 microns (100~2000X10-8m),
Preferably from 200 to 300 microns (200-300
The spherules have various sizes between , is of low cost. Its activity is within the range of M, A, T, standard tests (
ASTM Standard D3907-80), defined as the ratio of conversion obtained in the presence of the considered solid particles to the conversion obtained in the presence of the control catalyst.

For example, during the M, A, T test, sand particles with a specific surface area of less than 1 m2/g were found to have a 7° This will lead to a conversion rate of around 3%.

Tests were conducted at 530° C. with a C10 ratio of 4.5. This conversion was obtained under the same conditions as operated with a conventional catalyst based on faujasite (zeolite Y) with a specific surface area equal to 911121 g.
% conversion rate. This conversion rate is defined as the ratio of the weight of (gazer gasoline + coke)/heavyness of the initial feedstock. Therefore, it is preferred to discard a portion of the solid particles from time to time and replace it with a fresher equivalent quantity to maintain an acceptable metal content due to the low cost of this.

In fact, this analysis establishes that it contains more minerals, silicon, alumina, trace impurities in the form of titanium, iron, alkaline earths. The solid particles used are, for example, calcite, dolomite, limestone, bauxite, bayrite, chromite, zircon, magnesia, perlite, alumina, silica; all these solids have a low specific surface area.

On the contrary, catalysts are those commonly used in catalytic cracking processes. Generally, zeolite-based catalysts are preferred, especially those exhibiting good thermal stability in the presence of water vapor. This is between 10 and 100 microns.
Preferably, the average particle size is between 30 and 70 microns. The density is between 600 and 1800 kg/s3, preferably between 800 and 1600 kg/s3. be.

Separation and regeneration of the entire particles can be performed in different containers or in the same container. The relative content of different types of particles in the reaction zone is dependent on the gravimetric flow rates of particles introduced into the vaporization zone and into the cracking zone.

Generally, the ratio of the weight flow rate of particles introduced into the vaporization zone to the weight flow rate of particles introduced into the cracking zone is between 1 and 100, preferably between 1 and 10, more preferably between 1 and 1. It is between .5 and .5.

The weight percentage of catalyst particles present in the first mixture that reaches the vaporization zone and is carried by the solid particles during the separation or regeneration step is, for example, between 0.2 and 10%, preferably almost suppressing cracking. As if I hadn't done it,
It is between 1 and 5%.

In the second mixture, which contains most of the catalyst particles introduced into the cracking zone, some very fine inert particles are found as a result of attrition of the inert solid particles. The proportion of inert particles present in the second mixture is therefore necessarily dependent on the ratio of the flow rates of the first and second mixtures. For example, the proportion of inert particles in the second mixture is
If the ratio of the weight flow rate of the first mixture to the weight flow rate of the second mixture is large, it will be even larger.

The weight percentage of inert particles in the second mixture introduced into the cracking zone is between 1 and 40%, preferably between 2 and 10%. The remaining portion, which is 100%, clearly corresponds to catalyst particles.

Taking into account the above-mentioned advantageous preferred values, the inert solid particles in the cracking zone are strictly equivalent to all the distillate coming out of the vaporization zone and to the product corresponding to the second mixture of particles. 45% to 94.4% by weight of the mixture;
Preferably, it can represent 45% to 75% by weight.

In contrast, catalyst particles account for 4.6% of the produced mixture.
% to 55% by weight, preferably 25% to 55% by weight2
6 can be shown.

Particularly advantageously, according to the first implementation of the process, especially in engineering (see FIG. 1), the regeneration of inert solids and catalyst particles is carried out in the same zone with a separation step of the two types of particles. They can be done at exactly the same time.

This regeneration step generally involves fluidization of between 0.1 m/s and 2 m/s at a temperature T2 of between 650°C and 1200°C in the presence of oxygen or a gas containing molecular oxygen. It can be done with speed. Under these regeneration conditions, combustion of at least 70% of the residue present on the solid particles and the residual material stuck on the catalyst particles can be caused.

According to another method of implementing the invention, the catalyst particle-rich portion is heated at 500 to 750° C. in a second regeneration zone, which is connected to the first zone via a gas containing molecular oxygen.
It can be subjected to a second regeneration at a temperature T1 between.

The temperature T, is preferably at least 10°C more than the temperature T2
low. This second regeneration makes it possible to complete the regeneration of the catalyst particles.

This is because at least 90% of the residual material or cracking residue is oxidized.

According to a second implementation of the method (see Figure 2), the separation step of the two types of particles can be carried out in one container, and then the regeneration step of the particles can be carried out in two separate containers. .

One vessel is used for the regeneration of solid particles, and at the temperature T2 and the fluidization rate conditions described above, the other vessel is
It is used to regenerate the catalyst particles and is carried out at the temperature TI and the speed conditions described above.

The sputtering or atomizing means are preferably capable of introducing the feedstock at a speed lying between 10 and 100 m/s. Typically, the carrier gas flow is approximately 2
Suitable for producing particle velocities of from 10 m/s to
during the residence time of the feedstock.

The invention also relates to a catalytic cracking apparatus for carrying out the method (see FIG. 1), including:

-Reactor (1). This is an elongated vertical tubular conduit with a vaporization zone (1a) having a length L to internal diameter ratio L/D of between 2 and 30 and a cracking conduit following the vaporization zone. Contains zone (1b).

- Supply means (3). This is a liquid or gaseous feed supply means connected to the end of the reactor (1) in the vaporization zone (1a) and
) has a means for spraying the raw material into the container. This provides a flow that directs the feedstock from top to bottom or from bottom to top within the reactor (1).

- Supply means (4). This is the supply device for the bulk of the solid particles connected to the end of said reactor (1) in the vaporization zone (l a) and feeds the solid particles in the reactor (1) from above or from below. Provide a flow that leads upwards.

- Supply means (8). This is the means for supplying the majority of catalyst particles into the cracking zone (1b) of said reactor (1), and the supply means (4) for the majority of solid particles into said reactor (1). This feeding means (8) is suitable for directing the flow of the majority of catalyst particles in the direction of the flow of solid particles and feedstock.

・Separation means by stripping (8) (9) (10
).

These are means for separating solid particles and catalyst particles from the reaction effluent of cracking, and means for supplying the above-mentioned feedstock (
At the end opposite to where 3) is connected, connect the reactor (
1).

- Removal means (22). This is the separation means (8) (9) mentioned above.
) (10) is a means for removing the reaction distillate.

- Conveyance means (12). This is a transport means for solid particles and catalyst particles, towards at least one separation and regeneration means (13a) of solid particles and catalyst particles and then to at least one storage vessel (13b) for at least partially regenerated catalyst particles. ) or to at least one separation means ((28) in FIG. 2) of the solid particles from the catalyst particles and then to at least one regeneration means ((30) in FIG. 2) of the solid particles. ) and catalyst particles to at least one regeneration means ((28) in FIG. 2).

・Gas/particle separation and smoke exhaust means (14) (21
). These are connected to regeneration means (13a).

・Gas/particle separation and smoke exhaust means ((3) in Figure 2)
4) (35) (38) and (37)). These are connected to the catalyst regeneration means ((28) in FIG. 2) and the solid particle regeneration means ((30) in FIG. 2), respectively.

- Recirculation means (7) (23) (46). These are means for recycling a large portion, at least a portion, of the catalyst particles towards the supply means (6), which recirculation means (23)
is connected to a storage container (13b) or a regeneration means (28).

- Recirculation means (5) (18) (45). These are means for recycling a large portion, at least a portion, of the solid particles towards the supply means (4), which recirculation means (16)
is the first reproducing means (13a) or the reproducing means (30
) is connected to.

Due to this fact, the device is very compact and offers the advantage of integrating two functions, one for vaporization and pretreatment, and one for cracking, in a single vessel.

The invention has been made in accordance with FIG. 1, which schematically represents a special mode of implementation of the apparatus with a reaction zone of rising type feeding the feedstock at the lower end, and with two different regeneration zones and a separation zone for two types of particles. It will be better understood by drawing the second diagram.

Based on FIG. 1, the reaction zone or reactor (1) is an elongated, completely vertical, tubular conduit. It has a lower or vaporization zone (1a) and an upper or catalytic cracking zone (1b) following the vaporization zone (1a). The feedstock to be cracked can be preheated to between 100 and 450° C. and is supplied by at least one vibrator (3).

As described in US Pat. No. 4,331.533, the known atomization device deposits the feedstock into the lower part of the vaporization zone, preferably directly above the solid particle inlet (4), for example about 100 m/min. Supply at a rate of s.

The feed contacts these particles, which contain a majority (eg, at least 95%) of inert solid particles. These particles have an average particle size of 200 to 3, for example.
00 microns, density between 2000 and 6ooo
kg/m3, with an activity equal to about 10%, and this can be carried out by the feed means (4), by the vibrator (16), at a flow rate of 650 kg/m3 and equal to about 10%. ℃ to 1200℃, e.g. 850℃
It is supplied at a temperature of 0.degree. C. and a speed of 3 m/s. The solid particles and feedstock flow within the vaporization zone (1a).

Steam and carbon atoms 1 as carrier gas for solid particles
Injection from the vibrator (60) with light hydrocarbons from
And in particular, special equipment (fluid siphon (45)) isolating the various atmospheres of conventional equipment while providing an increase in the vaporizable fraction of the feedstock and thus the best conversion rates.
The presence of (46)(47)) makes it possible to manipulate vaporization in hydrogen gas.

The vapor formed in the vaporization zone (1a) of the reactor (1) leaves this zone after a residence time of approximately 0.58 and enters the cracking zone (1a) following the vaporization zone (1a).
b) the particle size is for example between 30 and 70 microns and the density is for example between 900 and 1400 kg/m
3 (eg, at least 80%). The pipe (23) delivers these particles by the feeding means (6) to the base of the cracking zone (1b), i.e. to the top of the vaporization zone (1a), for example at a speed of about 1.5 m/s, preferably At a temperature between 500°C and 750°C, for example 650°C, T−+ <”r−
Carry it in 2. The flow rate of the catalyst is regulated by a valve (7). A heat exchanger (not shown in the drawing) may also be placed in the pipe (23) upstream of the valve (7) in order to cool the catalyst particles coming out of the storage vessel (13b). can. The temperature of the vaporization zone (1a) is generally 4
Between 00℃ and 600℃, e.g. 450 to 600℃
It's between. In contrast, the cracking zone (1
The temperature in b) is for example between 450°C and 600°C.

At least one constriction (2), advantageously provided in the upper part of the vaporization zone (1a) between the supply means (4) and the supply means (6) of particles, produces locally supervelocities. This limits the fall of the catalyst in the vaporization zone (1a).

This supervelocity has the purpose of simultaneously creating high turbulence at the level of contact between the hydrocarbon vapor and the catalyst and ensuring intimate mixing of the two phases.

The longitudinal vaporization zone (1a) is defined from the lower end of the zone (1a) to the neck of the constriction (2).

The constriction (2) is between the convergence of the zone (1a) below the neck and the divergence of the cracking zone (1b) above the neck.

This is mainly at the level of the convergence and neck where inert particles are accelerated.

Good results could be observed with an opening angle of the converging section between 5 and 50 degrees, preferably between 5 and 20 degrees, and an opening angle of the divergent section between 20 and 180 degrees. Similarly, the ratio between the diameter of the neck and the diameter of the vaporization zone (1a) is 0.
．． It is between 25 and 1, preferably between 0.6 and 0.8. With these favorable numbers, cracking and
Dew (deposition) between 0.1 and 2% of the total flow of catalyst injected into zone (1b) could be obtained in the neck.

The vaporization zone (1a) defined by distance and diameter is L/
The D ratio is between 2 and 20, more advantageously between 5 and 1.
It is set to be between 5 and 5.

In the cracking zone (1b) of the reactor (1) flows the effluent, the vaporized feedstock and the catalyst, which contain solid particles that are responsible for at least a portion of the residual material. The residence time of the feed material in the vaporization zone (1a) is generally:
not exceeding 1000 m/s, preferably 500 m/s
It remains below s. On the other hand, cracking Φ
The residence time of the vaporized feedstock in zone (1b) is between about 0°01 seconds and 2 seconds, preferably between about 0.2 seconds and 1 second.
Seconds.

In a vessel (9) constituting a separation means by stripping the hydrocarbons adsorbed on the catalyst under the action of the steam conveyed by the pipe (11) at the outlet of the reactor (1),
Varistake separator means (8) ensure the initial separation of gaseous effluent and particles.

The cracking effluent is transported to at least one cyclone (
After passing through the container (9), the pipe (22)
) to leave. In contrast, the mixture of particles is transferred by means of a conveying pipe (12) to a container (13) as a first heat exchanger.
sent to. A valve (46) ensures regulation of the flow rate.

The inert solid particles and the catalyst reach the vessel (13), where separation of the two particle populations according to their size and their mass, oxidation of the coke adhering to the inert solid particles and regeneration of the catalyst take place simultaneously. It will be done. This container (13) is
It has at least two compartmentalized chambers (50) suitable for producing different heat levels, the latter ensuring storage of inert solids. This partition room (50) has a container (
13) is formed by a partition (15), for example made of a fireproof board, placed completely vertically. The solid particles thus flow in a cascade from chamber to chamber fed by pipes (12) equipped with valves (46) and flow siphons (47).

There, a valve (5) ensures the conveyance of inert solid particles into the vaporization zone (1a) of the reactor (1).
and a pipe (16) equipped with a fluidizing siphon (45) to draw off the inert solid particles. Compressor (17)
supplies combustion gas (for example air) via pipes (20a) to at least one diffuser (19) of the vessel (13) as a heat exchanger. Only a portion of the air necessary for complete oxidation of the coke deposited on the inert solid particles and regeneration of the catalyst is introduced into each chamber (50). The temperature increases with each layer up to the point of withdrawal (up to the top of the pipe (16) in the vessel (13)).

The operating conditions (i.e., the rate of fluidization) are such that the catalyst is kept substantially in the first compartment to avoid leaving the catalyst at high temperatures that would impair its catalytic activity or accelerate its aging. adjusted to provide the desired amount of energy.

The temperature curve in the regeneration means is adjusted such that the average temperature of the fed catalyst is fairly close to the temperature at which it is re-injected into the cracking Φ zone (1b). The second partition chamber can be formed, for example, by a partition (15a) suspended from the ceiling of the container (13) and projecting into each fluidized chamber (50). This means that the gaseous atmosphere
It rises from each of the chambers defined by the partitions (15a), allowing separation at the top of each of the chambers while avoiding mixing with the supplied catalyst.

This compartment further includes a combustible regeneration effluent, which is operated without oxygen or air at low temperatures, and a non-flammable regeneration effluent, which is operated without oxygen or air at low temperatures, and a non-flammable Allows recovery of regeneration effluent.

At the same time, the problem of after-combustion of carbon oxides in the space rising from the particle bed is avoided. This is because there is a reduction zone (low temperature room (5G)) and an oxidation zone (high temperature room (5G)).
50)) can be separated. The regeneration effluent is 1. Pass through the cyclone (14) and enter the pipe (21)
) is discharged from.

Catalyst particles collected by at least one cyclone (14) placed in each of the spaces defined by the partitions (15a) are operated in a fluidized bed and directed towards a storage vessel (13b) and a valve (7). ) and the cracking zone (
1b). This container (13b) is also
According to other embodiments of the method, if regeneration is too insufficient at the ISB level, an auxiliary regeneration device can be provided.

Therefore, in order to increase the difference between the temperatures T- and T'2 of the two particle populations, the combustion air (re-burned gas) in the hot chamber of the vessel (l1a) is removed by passing air through the catalyst bed. Pre-heating can be scheduled. Based on this particular implementation, the cold air is generally supplied by a pipe (20b) connected to a compressor (17) and a diffuser (1(b)) located at the base of the container (1(b)).
24), the particles can be heated while passing through the fluidized bed contained in the container (l1b), the brought-in particles are removed by the cyclone (25), and the particles are removed by the diffuser (19) from the container (13a). It can be installed in a hot room.

According to another implementation mode, the temperature difference between the two regeneration means can be increased by completely other means.

This is done in particular by installing at least one heat exchange surface of known type, not represented in the figures, in the catalyst particle regeneration means.

Based on another mode of operation, represented schematically by FIG. 2, in a first step two populations of particles are separated;
Subsequently and independently, in a second step, regeneration of the catalyst and oxidation of the coke deposited on the inert solid particles can be carried out.

The mixture of catalyst and inert solid particles reaches the vessel (2B) via the pipe (2), where separation of the two particle populations of the fluidized bed takes place.

This separation can be carried out by feeding the catalyst above the fluidized bed, by separation in the same fluidized bed or by a combination of these two methods. FIG. 2, for example, represents a schematic arrangement for separation by feeding. The fed catalyst particles are collected by at least one cyclone (27) and guided by a pipe (29) towards the regenerator (2B). Smoke, on the other hand, is discharged through the pipe (27a). The inert solid particles constituting the fluidized bed are led towards the regenerator (30) by a pipe (31).

The separation vessel (26) can be partitioned, like the previously described vessel (13a), to improve the separation of the two particle populations from one chamber to the other.

This is fed with steam or smoke from either the regenerator (28) or the regenerator (30). The regenerator (28) and the regenerator (30) are connected to the pipe (32) and the pipe (83).
Air or oxygen-containing gas is supplied by each of the two.

After removing dust from the smoke generated by the regeneration using a cyclone (36) and a cyclone (37), the smoke is transferred to a pipe (34).
) and pipes (35) leave the regenerator (28) and the regenerator (30).

The inert solid particles are reheated at a level above the heat level of the catalyst. This is because almost all of the latent coke contained in the raw material is fixed, so the coke content is higher. In order to enhance the temperature difference between the two populations, pre-heating of the air in the regenerator (30) can already be carried out by passing the air in the regenerator (28) through a fluidized bed, as described above.

The catalyst and the inert solid particles are subsequently transferred to a particle flow regulating valve (7) (5) and a fluid siphon (46), respectively.
(45) with pipe (23) (lli),
Return to reactor (1).

In order to maintain the fluidity of the catalyst as well as the solid particles, at least one inlet for the fluid vapor is placed on the various pipes, for example the injection port (54) on the pipe (12), the inlet (54) on the pipe (23). ) above the injection port (52), and the pipe (16
) can be introduced through the nozzle (53) above.

Although the present invention is illustrated in FIG. 1, which represents a unique method of implementation with a rising type reactor, similar ideas can be applied to the implementation of a reactor with a descending type of flow of particles and feedstock. It is also possible to do this.

[Brief explanation of the drawing]

FIGS. 1 and 2 are flow sheets showing embodiments of the present invention, respectively. (1)...reactor, (1a)...vaporization zone,
(1b) Cracking Φ zone, (2)... throttle section,
(3)... Supply pipe (supply means), (4) (6)...
・Supply means, (5) (7) (46)...Valve, (
8)...A means of paristic separator, (9)
...Container, (10) (14) (25) (27)
(36) (37)-'Cyclone, (13)--container, (13a)--storage container (regeneration means), (13
b)...Storage container (regeneration means), (11) (12
) (16) (20a) (20b) (21) (
22) (23) (27a) (29) (31)
(32) (33) ・=pipe, (15) (15a
)...Partition, (17)...Compressor, (
19) (24) (34) ((5)...diffuser, (2B)...container, (28) (30)...
Regenerator, (45) (46) (47)...Fluid siphon, (50)...Partition room. that's all

Claims (14)

[Claims] (1) A process for the catalytic cracking of a hydrocarbon feed having a high Conradson carbon value and containing residual material in the reaction zone of a fluidized bed, the reaction zone having different temperatures T'_2 and T'_1; In a method of introducing two types of particles of different sizes at two different levels of the reaction zone, the first part of the reaction zone, called the vaporization zone, contains the above-mentioned feedstocks, a carrier gas and a very inert gas. A first mixture of a large portion of solid particles and a small portion of catalyst particles separate from this highly inert solid particles is introduced at a temperature T'_2 lying between 650° C. and 1200° C. and Very inert solid particles are 50m^2/
Specific surface area less than 100 g, cracking activity at most 15%, 100 to 2000 microns
With a particle size between ^-^6m) and a density between 2000 kg/m^3 and 6000 kg/m^3, the above catalyst particles have a cracking activity of more than 20%, a cracking activity of 10 to 100
The above particles have a particle size between microns (10-100 x 10^-^6 m) and a density between 600 kg/m^3 and 1800 kg/m^3 and are placed in the above first part of the reaction zone. flowing a first mixture of the feedstock and a carrier gas to vaporize all the feedstock and remove at least a portion of the residual material under minimal cracking conditions, from the first part above; Into the second part of the above-mentioned zone, called the cracking zone, all the effluent of the first part of the reaction zone is introduced, and at the same time the second part of the above-mentioned
at the inlet of the section with the majority of the catalyst particles defined above;
introducing a second mixture with a small portion of highly inert solid particles, said second mixture being introduced at a temperature T'_1 below said temperature T'_2 and between 300° C. and 750°; and in said cracking zone, a mixture of all effluents from the first part of the reaction zone is passed in cocurrent with said second mixture of particles, the cracking effluent on the one hand and the solids on the other hand. recovering catalyst particles containing at least a portion of the particles and cracking residue; separating and recovering the cracking effluent from the solid particles and catalyst particles; and recovering the solids and catalyst particles exiting the effluent separation step; A fraction containing most of the solid particles and a fraction containing most of the catalyst particles are separately recovered by subjecting them to at least one particle separation step and at least one fluidized bed regeneration step, A process characterized in that said solid particles are at least partially recycled to the vaporization zone and said catalyst particles are recycled to said reaction zone and racking zone. (2) A method according to claim 1, in which the bulk of the feedstock and solid particles are introduced at the base of the vaporization zone. (3) In the method according to claim 1 or 2, the solid particles are selected from the group consisting of calcite, dolomite, limestone, bauxite, birite, chromite, magnesia, pearlite, alumina, and silica having a small specific surface area. How to be chosen. (4) A method according to one of claims 1 to 3, in which the vaporization zone has a length L and an internal diameter D such that the L/D ratio is between 2 and 30. (5) A method according to one of claims 1 to 3, in which the velocity of the particles of the primary mixture is increased in the upper part of the vaporization zone. (6) A method according to one of claims 1 to 5, in which the first particle mixture as described above is placed in a vaporization zone, and
The second particle mixture is placed in a cracking zone such that the proportion of catalyst particles in the cracking zone is about 4.6 to 55% by weight of the total mixture so constituted.
, preferably 25 to 55% by weight. (7) - Vaporization zone (1a) which is a long vertical tube-shaped conduit with a ratio L/D of length L to inner diameter D between 2 and 30 and cracking following the vaporization zone - a reactor (1) comprising a zone (1b); - means for supplying liquid or gaseous feedstock connected to the end of the reactor (1) in said vaporization zone (1a), said reactor (1); The feed material is sprayed from top to bottom in the reactor (1).
or supply means (3) providing a flow leading from bottom to top; - a supply device for the bulk of the solid particles connected to the end of said reactor (1) in the vaporization zone (1a); feeding means (4) for providing a flow that guides the solid particles from top to bottom or from bottom to top in the cracking zone (1b) of said reactor (1);
) is a means for supplying most of the catalyst particles into the reactor (
supply means (6) connected to 1) and suitable for directing the flow of the majority of the catalyst particles in the direction of the flow of the solid particles and the feedstock; It is a separation means, and a means for supplying the above-mentioned raw materials (
At the end opposite to where 3) is connected, connect the reactor (
1) separating means by stripping (
8)(9)(10),・The above separation means (8)(9)(1
means for removing the reaction distillate (22) connected to 0), - a means for transporting solid particles and catalyst particles, and at least one separation and regeneration means (13a
) and then to at least one storage vessel (13b) of the at least partially regenerated catalyst particles or to at least one separation means (26 in FIG. 2) of the solid particles from the catalyst particles. Next, at least one regeneration means for solid particles ((30) in FIG. 2) and at least one regeneration means for catalyst particles ((28 in FIG. 2)
)) a conveying means (12) for transporting these towards the regenerating means (13a); gas/particle separation and smoke evacuation means (14) (21) connected to the regenerating means (13a); or regenerating the catalyst particles; Gas/particle separation and smoke exhaust means ((28) in FIG. 2) connected to the means ((28) in FIG. 2) and the solid particle regeneration means ((30) in FIG. 2), respectively. 34) (35) (36) and (37)), - means for recycling a large part, at least a part, of the catalyst particles towards the supply means (6), said recirculation means (23) being located in the storage vessel ( 13b) or recirculation means (7) (23) (46) connected to the regeneration means (28);
), and this recirculation means (1
6) is the first reproducing means (13a) or the above reproducing means (
recirculation means (5) (16) (4) connected to
5) A catalytic cracking device (Fig. 1) consisting of: (8) An apparatus according to claim 7, wherein the reactor (1) is located above the vaporization zone and includes supply means (4) for solid particles and supply means (6) for catalyst particles. At least one constriction section (2
). (9) A device according to claim 7 or 8, in which the storage container (13b) has regeneration means comprising at least one combustion gas supply means (24) at least at the base of said container. (10) A device according to one of claims 7 to 9, in which the storage container (13b) is connected to the second supply means (1
9) Device with cyclone means (25) of the combustion gases before passage. (11) In a device according to one of claims 7 to 10, solid particle recycling means (5, 16, 45)
However, the valve (5) connected to the supply means (4), the valve (5) and the regeneration means (13a) ((30 in Fig. 2)
) with a fluid siphon (45). (12) In a device according to one of claims 7 to 11, means for recycling catalyst particles (7, 23, 46).
A valve (7) connected to the supply means (6) and a fluid siphon (4) provided between the valve (7) and the storage container (13b) or the regeneration means ((32) in FIG. 2)
6). (13) Based on one of claims 7 to 12,
Apparatus, in which the regeneration means (13a) have at least two partitions and at least one fluidization rate adjustment means in said partitions. (14) A device according to one of claims 7 to 13, in which the reactor (1) is of the ascending type.