FR2780316A1 - Regeneration of particulate catalysts used for reforming, paraffin isomerization and dehydrogenation - Google Patents

Abstract

Regeneration of particulate catalysts flowing from top to bottom of a vibrating helical transporter containing at least one coil comprises submitting the body to a temperature profile, a pressure profile, or by placing it in contact with a fluid or solid agent, over at least part of the trajectory of the body in the vibrating helical transporter. The solid is a catalyst for reforming, paraffin isomerization or dehydrogenation of paraffins and the particles are submitted to a temperature profile and put in contact with at least one fluid over at least part of their trajectory. The treatment is a regeneration, activation or reactivation and involves at least one combustion stage in at least one combustion zone and at least one chlorination stage in at least one chlorination zone. The treatment is continuous. The combustion and chlorination zones can be combined. In addition the treatment involves at least one calcination stage in at least one calcination zone. The catalyst is submitted successively to a combustion stage in the presence of a combustion gas, a chlorination stage in the presence of a chlorination gas and then a calcination stage in the presence of a calcination gas. The process also includes a stage of stripping hydrocarbons before the combustion stage. Catalytic reaction for reformation, paraffin isomerization or paraffin dehydrogenation carried out in several reaction zones in series where the load and the catalyst used in the reaction circulate successively through each reaction zone from top to bottom. The catalyst extracted at the bottom of the last zone is treated using the above process, extracted from the bottom of the regenerator and sent to the first reaction zone crossed by the load. Installation comprising at least one vibrating helical transporter with at least one coil, a catalyst inlet at the top and a catalyst outlet at the bottom. The helical transporter is mounted on a vibrating table which produces the vibrations needed to make the catalyst descend. The transporter includes at least one combustion zone with combustion gas inlet(s) and outlet(s); at least one chlorination zone with chlorination gas inlet(s) and outlet(s) and at least one calcination zone with calcination gas inlet(s) and outlet(s). The combustion and chlorination zones can be combined.

Description

The present invention relates to a method in which a

  reaction in at least one vibrating helical conveyor comprising at least

  a turn, operating in descending mode.

  The prior art discloses methods using a vibrating helical conveyor operating in ascending mode, however methods using a vibrating helical conveyor which allows the transport of particles from the top

  to the bottom of the transporter never appear to have been described.

  The method according to the present invention consists in lowering a divided solid body into at least one vibrating helical conveyor, this divided solid body being subjected to a reaction over at least part of its path in the vibrating helical conveyor. All kinds of reactions can thus be carried out, for example, one can carry out conventional chemical reactions on the divided solid body or chemical reactions in which the divided solid body intervenes as reagent or catalyst, one can also carry out regenerations, activations of the body solid divided. More generally, the divided solid body is subjected to at least one operation on at least part of its path in the vibrating helical conveyor. This operation includes, for example, the following actions: subjecting the divided solid body to a temperature profile and / or a pressure profile and / or to bringing it into contact with an agent. This agent is for example a fluid or a solid fixed on a part of the conveyor coming into contact with the divided solid body: this solid is for example coated on a surface coming into contact with the divided solid body. Several operations of identical or different natures can thus be carried out on the divided solid body. The divided solid body is for example

a catalyst or an adsorbent.

  More particularly, the present invention relates to a process for the treatment of particles of catalytic reforming catalysts, of isomerization of paraffins, of dehydrogenation of paraffins, which consists in bringing down the catalyst particles in at least one vibrating helical conveyor, to subject them to the at least part of their journey and preferably over most of their journey at a temperature profile and to put them in contact with at least one fluid on at least part of their journey. Said treatment is chosen from the group of regenerations, activations or reactivations of catalysts, it can thus be carried out continuously or batchwise, from

  preferably, the treatment is carried out continuously.

  Catalytic reforming is a process aimed at increasing the octane number of gasolines by promoting the reactions of dehydrogenation of naphthenes, isomerization of alkylnaphthenes and paraffins, and dehydrocyclization

paraffins.

  The dehydrogenation of paraffins makes it possible to obtain olefins comprising the same number of carbon atoms as the starting paraffins. These olefins can be used later for the production of bases for

  super fuels (ethers, alkylates) or biodegradable detergents.

  The isomerization of paraffins and naphthenes with six carbon atoms into naphthenes with 5 carbon atoms is generally promoted by catalysts

  bi-functional comprising a metallic or sulphide phase of hydro-

  dehydrogenating, and an acid phase of zeolite or halogenated alumina type. These reactions lead to an increase in the engine octane number and the index

of octane is looking for essences.

  The processes for reforming, dehydrogenating paraffins and isomerizing paraffins use solid catalysts based on precious metals such as platinum or rhenium or oxides such as molybdenum oxide or chromium oxide, supported on a refractory oxide such

alumina.

  Over time, these catalysts deactivate, in particular due to the progressive deposition of polyaromatic hydrocarbons of complex structure bearing the usual name of coke. The deposition of coke makes it compulsory to regenerate the catalyst after an operating cycle ranging from a few days to more than a year. In units with continuous catalyst regeneration, it is not necessary to stop the units in order to regenerate the catalyst. The catalyst is transported from one reactor to the other by a suitable means, of a mechanical or pneumatic nature, then it is transported to a regeneration column operating the rejuvenation of the catalyst. Finally, the regenerated catalyst is transported to one or more reactors, preferably the catalyst

  regenerated is transported to the head of the first reactor.

  The treatment process according to the invention can also be implemented off-site, for example the catalyst can be transported to a company specialized in the treatment of catalysts where it will be regenerated. The regeneration of catalysts for reforming, for isomerizing paraffins or for dehydrogenating paraffins can comprise several stages. It generally comprises a step of combustion of the coke intended to remove the hydrocarbon deposit by combustion managed in an oxidizing medium, a step of chlorination (and in particular of oxychlorination) intended to improve the dispersion of the metallic active phase (in the case of catalysts based on platinum) and optionally a calcination step intended to improve the fixation of the active phase, dry the catalyst and fix its chlorine content at the value required for optimal catalytic performance. A step of cooling the catalyst in air or under nitrogen as well as a step of stripping the hydrocarbons trapped in the porosity of the catalyst under a stream of inert or neutral gas, for example under nitrogen, can also follow.

the calcination step.

  All these steps are implemented successively in the

  existing processes for the continuous regeneration of reforming catalysts.

  In these processes, for example the Octafining process of the French Petroleum Institute or the CCR Platforming process of UOP, the catalyst flows by gravity from top to bottom of a column called regenerator, for example RegenC from IFP or UOP CycleMax, by successively crossing zones where the combustion, oxychlorination, calcination and

above-described cooling.

  The implementation of the method according to the invention requires the implementation of a method of transporting catalyst from the reaction zone to the top of the regenerator and from the bottom of the regenerator to the reaction zone. The apparatus for implementing the method according to the present invention is in fact a regenerator supplied with catalyst in its upper part, the regenerated catalyst leaving in the lower part of the regenerator. However, the reaction zones of the reforming processes, of dehydrogenation of paraffins or of isomerization of paraffins are generally arranged side by side or superimposed, the charge and the catalyst generally circulating successively from top to bottom through each reaction zone. For example, the method according to the present invention can be implemented in parallel with the implementation of a catalytic reforming process in a circulating bed, or during

  off-site regeneration of reforming catalysts.

  The regeneration device is a vibrating helical conveyor, that is to say a vibrating conveyor comprising at least one turn of substantially tubular shape. The catalyst particles descend into the helical conveyor, their movement being generated by the vibrations exerted

on the carrier.

  Preferably, the catalyst particles are subjected to a temperature profile over at least part of their path according for example to the procedure described in French patent FR 943865. This temperature profile can also be obtained by indirect contact with a heat transfer fluid. bathing the steps of the coil, as described in French patent application FR 2 634 187. In this patent application FR 2 634 187 the catalyst passes through the regenerator in an upward movement, the turns of the helical ramp are connected to each other by two helical bands fixed to the ramp on two opposite sides thereof. A helical channel, in which a heat transfer fluid can circulate, is thus formed between the turns of the helical ramp. More generally, as described in French patent FR 943865, the entire tube-coil device can be placed in an enclosure, o the products transported will be subjected to a heat treatment, for example an insulated enclosure in which circulates a heat transfer fluid bathing the steps of the coil. It follows from the same patent application that the heat transfer fluid can pass through the coil itself. The catalyst to be regenerated crosses the regenerator in an upward movement, the gas being able to circulate cocurrently or countercurrently. The coil can also be heated by the Joule effect, by directly heating the metal mass of the tube

  as described in European patent application EP-A-0612561.

  The present invention relates to a process for treating a catalyst chosen from the group formed by reforming catalysts, isomerization of

  paraffins and dehydrogenation of paraffins or a powdery adsorbent.

  Said method consists in lowering the particles of catalyst or adsorbent in a vibrating helical conveyor comprising at least one vibrating helical turn. According to said method, the particles are further subjected to a temperature profile and brought into contact with at least one fluid over at least part of their path. The method according to the invention therefore relates to a treatment included in the group formed by regenerations, activations, reactivations of catalysts, and comprises at least one combustion step carried out in at least one combustion zone and at least one

  chlorination step carried out in at least one chlorination zone.

  Descending into the helical conveyor, the catalyst particles successively pass through a coke combustion zone, where a gas containing oxygen, for example air, is introduced. Preferably, this gas is introduced in a stepwise fashion at several successive turns in order to limit the oxygen concentration and not to risk degrading the catalyst by local overheating, a chlorination or oxychlorination zone o a chlorinating agent such perchlorethylene is introduced with air and possibly a calcination zone where the catalyst is swept

  by a stream of nitrogen or dry air containing less than 50 ppm of water.

  It is possible to combine in one zone the combustion zones and

  chlorination, by introducing the chlorinating agent into the combustion zone.

  Advantageously, the combustion zone is preceded by a zone in which the catalyst is preheated so that it is brought to a temperature at which the subsequent combustion of the coke takes place in

optimal conditions.

  It is also possible to modulate the injections of air or oxygen into the coke combustion zone, by introducing, for example, increasing amounts of air from top to bottom of the helical conveyor. The temperatures of the gases entering the combustion zone can be between 300 and 750 C, from

  preferably between 450 and 550 C.

  It is also possible to extract part of the combustion gases by means of purges placed in one or more places of the regenerator as well

  that it is, for example described in Example 2.

  S The helical conveyor - or possibly the conveyors - has at least one pitch and is wound around a hollow drum in which is arranged a system intended to produce the vibrations necessary for the descent of the catalyst particles. The vibrations can be produced by at least one system placed at any suitable level, for example at the base or at the top of the barrel or else positioned around the coil. Among the systems that can be used are the following systems: unbalance motors, electromagnetic vibrators (excited by a variable cycle, with creation of pulses) and unbalance excitations. Preferably, the vibrations are produced by a table serving as support for the central drum and actuated by two motors with

unbalanced.

  The vibrations imparted to the barrel-turn assembly include the dimensionless constant of acceleration, ratio of the vertical component of the acceleration to the acceleration of gravity, between 0 and 4, preferably between 1.2 and 3, 5, and even more preferably between I and 3, the speed of advancement of the particles of between 0.05 and 0.5 m / s, preferably between 0.1 and 0.4 m / s and again more preferred between 0.1 and 0.3 m / s. Hourly mass flow of particles is generally understood

  between 1 kg / h and 50 tonnes / h, preferably between 5 kg / h and 10 tonnes / h.

  In the case of the preferred implementation according to the invention, the vibrations are produced by a table serving as support for the central drum and actuated by two unbalance motors. In this case, the solid particles conveyed inside the coil advance at a speed proportional to the dimensionless constant of acceleration, for a given inclination of motors and an angle of climb. The dimensionless acceleration constant depends on

  the distance between the unbalances and their rotation speed for the given system.

  For a variation of said constant between 1.2 and 3.5 the speed

  particle advancement is typically between 0.1 and 0.3 m / s.

  Thus said speed is easily adjustable by acting on the unbalance spacing, the inclination of the motors or the speed of rotation of the motors. As for the hourly volume flow rate of the particles, it depends on the constant

  dimensionless vibration, but also the diameter of the tube forming the turn.

  The power of the motors and the size within the tube are limiting factors. Thus a reference tube DN 40 (1 1/4 ") conveys a maximum of 700 kg / h of sand, the particles of which have a diameter of 1.6 mm. On the other hand, the inclination of the motors must generally not exceed 35 for efficiently advancing the solid particles in the tube without generating

excessive vibration.

  The turns of the propeller described by the transporter can be contiguous or non-contiguous. The turns have a developed length between 0 and 200 m and the height of the propeller is generally between 0 and 20 m. The angle of rise of the coil which measures the inclination of the coil relative to the horizontal is between 10 and preferably between I and 5 and even more preferably between I and 4. The cross section of the turns is

  preferably circular with a diameter between 10 and 500 mm.

  The gases or fluids intended for the regeneration of reforming catalysts, of isomerization of paraffins or of dehydrogenation of paraffins can be introduced by one or more conduits in such a way that said gases or fluids circulate cocurrently or countercurrently in one or more steps from the coil. The pressure within the coil can be between 0, 1 and 20 bars, preferably between 1 and 7 bars. The gases or fluids may be introduced into the coil laterally, from above or from below the coil by passing through a fine-mesh grid or through any device capable of preventing the penetration of particles of catalyst in the supply lines. gas arrival. The same applies to the withdrawal line (s)

gas.

  Thus, the process according to the present invention is a process for treating a catalyst chosen from the group formed by catalysts for reforming, isomerizing paraffins and dehydrogenating paraffins or a pulverulent adsorbent, consisting in bringing down the particles pulverulent catalyst or adsorbent in a vibrating helical conveyor comprising at least one vibrating helical turn. According to this process, said particles are subjected to a temperature profile and brought into contact with at least one fluid over at least part of their path. The treatment process according to the invention is included in the group formed by regenerations, activations, reactivations of catalysts, it comprises at least one combustion step carried out in at least one combustion zone and at least one

  chlorination step carried out in at least one chlorination zone.

  Preferably the regenerations, activations or reactivations of catalysts are

performed continuously.

  According to a variant of the method according to the present invention, at least one combustion zone precedes at least one chlorination zone on the path of the catalyst in the vibrating helical conveyor, according to another variant of said method at least one combustion zone and at least one chlorination zone are confused. The method can also comprise at least one calcination step carried out in at least one calcination zone as well as a

  hydrocarbon stripping step carried out before the combustion step.

  The present invention also includes a catalytic process chosen from the group formed by reformings, isomerizations of paraffins and dehydrogenations of paraffins carried out in several reaction zones in series, superimposed or side by side, the charge and the catalyst flowing successively through each reaction zone from top to bottom, the catalyst withdrawn at the bottom of the last reaction zone traversed by the charge then being treated according to one of the variants of the treatment process according to the present invention then being withdrawn at the bottom of the regenerator and sent to the

  first reaction zone crossed by said charge.

  The present invention also comprises an installation containing at least one vibrating helical conveyor, comprising at least one turn, at least one conduit for introducing the catalyst situated in the upper part of the conveyor (that is to say in the part situated between the medium -in height- and the top of the conveyor) and at least one catalyst outlet pipe situated in the lower part of the conveyor (that is to say in the part situated between the middle -in height- and the bottom of the conveyor) this helical conveyor being arranged on a vibrating table equipped with a system intended to produce the vibrations necessary for the descent of the catalyst particles. This installation also contains at least one combustion zone in which is disposed at least one turn of the vibrating helical conveyor comprising at least one gas introduction pipe and at least one gas outlet pipe, at least one chlorination zone in which is arranged at least one turn of the vibrating helical conveyor comprising at least one gas introduction pipe and at least one gas outlet pipe. According to a particular realization of

  installation, combustion and chlorination zones are combined.

  On the other hand, said installation may also include at least one calcination zone located below the combustion and chlorination zones in which is disposed at least one turn of the vibrating helical conveyor comprising at least one gas introduction pipe and at minus one

gas outlet line.

  1 5 The figures and examples described below illustrate the invention without limiting it

the scope.

  Figure 1 illustrates Example I described below. The helical conveyor (12) is arranged on a vibrating table (1) and two unbalanced motors (2) generate the vibrations necessary for the descent of the catalyst. The entry of solid particles takes place via line (3) and the exit of particles through line (4). The entire helical barrel-conveyor is contained in a heat-insulated enclosure (5) integral with the vibrating table. A gas is introduced at the bottom of the device through the pipe (6). Said gas circulates between the walls of the insulated enclosure: this gas is introduced in (7) laterally in the upper part of the helical regenerator, and passes through the helical regenerator co-current with the catalyst. An oxygen-containing gas is introduced by means of six pipes (8) into the combustion zone (14), the first inlet pipe for this gas being positioned laterally at the level of the first turn of the helical conveyor. The catalyst then enters the chlorination zone (zone 15), in this zone a gas is also introduced through line (9). The pipes (8), (9) and (I l) are supplied by pipes and a device located inside the central barrel. The gases from the combustion and chlorination zones leave the regenerator via the line (10). The catalyst then enters the calcination zone (zone 16), in this zone, the catalyst is swept against the current by dry air introduced through the conduit (I 1). The calcination gas leaves the regenerator through the pipe (10)

  together with combustion and chlorination gases.

  FIG. 2 shows an embodiment of the method according to the invention in which the combustion zone comprises a series of gas evacuation pipes

combustion.

  Figure 2 illustrates Example 2. The helical conveyor (10) is arranged on a vibrating table (1) and two unbalanced motors (2) generate the vibrations necessary for the descent of the catalyst. The entry of particles

  solids is done through line (3) and the exit of particles through line (4).

  An air-containing gas is introduced cocurrently from the catalyst flow through line (3). An air-containing gas is also introduced through 7 pipes (5) into the combustion zone. The combustion gas is drawn off by means of 7 pipes (6). Passing through the combustion zone (12), the catalyst is therefore swept by a combustion gas alternately co-current and counter-current. The vibrating helical conveyor is heated

  by Joule effect as described in European patent application EP-A-

  0612561. Preheating of the catalyst is ensured in the coil of the zone

(I 1) which is insulated.

  The catalyst then enters the chlorination zone (zone 13), a gas, flowing against the current with respect to the direction of circulation of the catalyst, is also introduced into this zone via the pipe (8). The gases from the

  combustion and chlorination leave the regenerator via the lines (6) and (7).

  The catalyst then enters the calcination zone (zone 14), in this zone, the catalyst is swept against the current by dry air introduced through the conduit (9). The pipes (5), (8) and (9) are supplied by pipes and a device located inside the central barrel. The calcination gas leaves the regenerator via the pipe (7) together with the

combustion and chlorination.

  FIG. 3 shows an embodiment of the method according to the invention in which

  the combustion and chlorination zones are combined.

  According to this embodiment, the helical vibrating conveyor (9) is arranged on a vibrating table (1) and two unbalanced motors (2) generate the vibrations] 1 necessary for the descent of the catalyst. The entry of solid particles is done

  through line (3) and the exit of particles through line (4).

  Zone (10) is a zone in which the catalyst is preheated by means of a stream of nitrogen introduced into the upper part of the regenerator. Line (5) allows nitrogen to be introduced into line (3). The catalyst passes through the regenerator zone (11), which is both a combustion zone and a chlorination zone and in which a burning and a redispersion of the metallic phase of the catalyst are carried out simultaneously. A gas containing a chlorinating agent is introduced into each of the turns making up the zone (11) by six pipes (6), the gas is then withdrawn from this zone by means of six pipes (7). The catalyst then enters the calcination zone (12) in which it is swept by a stream of dry air introduced into this zone through the pipe (8). The calcination gas leaves the

area (12) through the pipes (7).

Example 1:

  The catalyst of Example I is regenerated in a regenerator in accordance with FIG. 1. The helical conveyor comprises 17 turns, its height is 5

  meters and its developed length is 170 meters.

  The catalyst is in the form of spherical beads with a diameter of 1.8 mm, it comprises a metallic phase of platinum dispersed on alumina, the platinum content being 0.30% by weight. The metal surface exposed before regeneration is 8 1% of the total surface. The specific surface of the catalyst

is 200 m2 / g.

  The catalyst enters the regenerator at a temperature of 350 C at a rate

  500 kg / h. Its carbon content (coke) is 6.0% by weight.

  The first steps (top) of the helical conveyor are bathed in a flow of nitrogen used for preheating (zone 13) of the catalyst. This nitrogen flow is introduced in (7) at a flow rate of 500 Nm3 / h, at a pressure of 5 bars, this gas is

  preheated to 480 C using an oven outside the device.

  The catalyst passes through the coke burning zone (14). Each of the pipes

  (8) deliver a flow rate of 40 Nm3 / h of air preheated to 480 C.

  The residence time of the catalyst in the combustion zone (zone 14) is minutes, ie a tube length of 60 m. The catalyst then enters the chlorination zone which is here an oxychlorination zone (zone 15), the line (9) allowing the introduction of an air flow containing perchlorethylene at a flow rate of 500 Nm3 / h. The residence time of the catalyst in the oxychlorination zone is 30 minutes, ie a tube length of 60 min. The catalyst then enters the calcination zone (zone 16). The residence time of the catalyst in the calcination zone is 15 minutes, ie a tube length of 30 m. The catalyst is swept against the current by a stream of dry air at 500 Nm3 / h introduced at the bottom of the regenerator by the

driving (l 1).

  The characteristics of the catalyst at the outlet of the regenerator are as follows: specific surface, 195 m2 / g; dispersion of the metallic phase,%; carbon content 0.1% by weight. The mechanical characteristics of the catalyst balls (resistance to attrition, crushing grain to grain) are unchanged. The chlorine content is 1.2% by weight. The device described in

  Example 1 therefore allows the complete regeneration of the reforming catalyst.

Example 2 The catalyst of Example 2 is regenerated in a regenerator in accordance with

  Figure 2. The helical conveyor includes 17 turns, its height is 5

  meters and its developed length is 170 meters.

  The catalyst is in the form of spherical beads with a diameter of 1.6 mm, it comprises a metallic phase of platinum dispersed on alumina, the platinum content being 0.28% by weight. The metallic surface exposed before regeneration is 81% compared to the exposed metallic surface of the catalyst

  new. The specific surface of the catalyst is 220 m2 / g.

  The catalyst enters the regenerator at a temperature of 350 C at a rate

  500 kg / h. Its carbon content (coke) is 6.0% by weight.

  The catalyst passes through the coke burn zone. An air flow of 50 Nm3 / h

  is introduced through line (3), in the combustion zone, it circulates

  catalyst flow current. This gas is introduced at room temperature. Air at room temperature is also introduced by means of the 7 pipes (5), the air flow rate of each of these pipes being 50 Nm3 / h. This gas then exits by means of the pipes (6) each drawing a flow rate of 50 Nm3 / h. The average temperature in the catalytic bed in the coke combustion zone is adjusted in the window 480-550 C. The turns in the combustion zone are not insulated. The catalyst arrives on the conveyor at a temperature of 150 C at a flow rate of 500 kg / h. Its carbon content (coke) is 6.0% by weight. The residence time of the catalyst in the combustion zone (zone 12) is 30 minutes, ie a tube length of 60 m. The catalyst then enters the oxychlorination zone (zone 13), the pipe (8) introducing a flow rate of 500 Nm3 / h of air containing a mixture of dichloroethane and water. The residence time of the catalyst in the oxychlorination zone is 30 minutes, ie a tube length of 60 m. The catalyst then enters the zone of

  calcination (zone 14), the dry air flow introduced into this zone against

  catalyst current at a flow rate of 500 Nm3 / h. The residence time of the catalyst in the calcination zone is 15 minutes, a length of

30 m tube.

  The characteristics of the catalyst at the outlet of the regenerator are as follows: specific surface, 220 m 2 / g; dispersion of the metallic phase,%; carbon content, 0.05%. The mechanical characteristics of the balls

  catalyst (resistance to attrition, crushing grain to grain) are unchanged.

  The chlorine content is 1.0% by weight. The device described in example 2

  therefore allows complete regeneration of the reforming catalyst.

Example 3:

  The catalyst of Example 3 is regenerated in a regenerator according to FIG. 3 in which the combustion and the chlorination are carried out in the same zone. The helical conveyor includes 11 turns, its height is 4

  meters and its developed length is 170 meters.

  The catalyst is in the form of extrudates with a diameter of 1.4 mm and a length of between 1 and 8 mm. It comprises a metallic phase of platinum and rhenium dispersed on alumina, the platinum content is 0.25% by weight and the rhenium content is 0.30% by weight. The metal surface exposed before regeneration is 75%. The specific surface of the catalyst is 230 m2 / g. The catalyst enters the regenerator at a temperature of 140 ° C.

  at a flow rate of 300 kg / h. Its carbon content (coke) is 12.0% by weight.

  The catalyst is preheated to the temperature of 515 C in the first turns constituting the zone (10) by means of a flow of nitrogen with a flow rate of 20 Nm 3 / h, at a pressure of 6 bars. The catalyst then passes through the regenerator zone (11). In this zone, an air flow containing hydrogen chloride is introduced into each of the turns making up the combustion zone through six pipes (6) at a flow rate of 80 Nm3 / h. Each of the air additions is introduced at a temperature of 400 ° C. and at a pressure of 5.9 bars. The combustion air is heated and compressed by an oven and a compressor external to the device. Hydrogen chloride is obtained by temperature decomposition of dichloropropane between the oven and the regenerator. The residence time of the catalyst in this zone (11) is 40 minutes. This zone (11) is further heated to the temperature of 550 C by

  Joule effect as described in patent EP-A-0612561.

  The catalyst then enters the calcination zone (12), in this zone, it is swept against the current by a stream of dry air introduced at the bottom of the regenerator through the line (8) at a flow rate of 50 Nm3 / h and at the temperature of

  525 C. The residence time of the catalyst in this zone is 15 minutes.

  The characteristics of the catalyst at the outlet of the regenerator are the following specific surface, 210 m2 / g; 95% bimetallic phase dispersion; content

carbon less than 0.05.

  The amount of small particles of catalysts - called "fine" by those skilled in the art - produced during regeneration is less than 0.1% by weight. The

  regeneration of the reforming catalyst is therefore complete.

Claims (12)

  1. Method consisting in lowering a divided solid body (or pulverulent particles) into at least one vibrating helical conveyor containing at least one vibrating turn, said method comprising at least one operation chosen from the group formed by the operations consisting in subjecting said body to a temperature profile, the operations consisting in subjecting said body to a pressure profile and the operations consisting in bringing said body into contact with at least one agent chosen from fluids and solids, said operation being carried out on at least part of the path of the solid body divided in the vibrating helical conveyor 2. Method according to claim 1 for treating a solid which is a catalyst chosen from the group formed by catalysts for reforming, isomerizing paraffins and dehydrogenating paraffins, process in which said particles are subjected to a profile of temperature and brought into contact with at least one fluid over at least part of their path, said treatment being included in the group formed by regenerations, activations, reactivations and comprising at least one combustion step carried out in at least one zone combustion and at   minus a chlorination step carried out in at least one chlorination zone.   3. Method according to claim I or 2 such that the treatment is carried out continuously.   4. Method according to one of the preceding claims such as at least one zone   of combustion precedes at least one chlorination zone on the path of the   catalyst in the vibrating helical conveyor.   5. Method according to one of the preceding claims such as at least one zone   combustion and at least one chlorination zone are combined.   6. Method according to one of the preceding claims as it comprises   in addition to at least one calcination step carried out in at least one zone of calcination.   7. The method of claim 6 such that the catalyst successively undergoes at least one combustion step in the presence of a combustion gas, then at least one chlorination step in the presence of a chlorination gas and then at   minus a calcination step in the presence of a calcination gas.   8. Method according to one of the preceding claims as it comprises   in addition to at least one hydrocarbon stripping step carried out before the combustion stage.   9. Catalytic reaction chosen from the group formed by reforming, isomerization of paraffins and dehydrogenation of paraffins carried out in several reaction zones in series, the charge and the catalyst used in said reaction flowing successively through each reaction zone from top to bottom , the catalyst withdrawn at the bottom of the last reaction zone through which the feedstock is then treated according to the process   according to one of claims 1 to 8, then being drawn off at the bottom of the regenerator   and sent to the first reaction zone crossed by said charge.   10. Installation comprising: M at least one vibrating helical conveyor, comprising at least one turn, at least one catalyst introduction pipe located in the upper part of the transporter and at least one catalyst outlet pipe located in the lower part of the conveyor, this helical conveyor being disposed on a vibrating table equipped with a system intended to produce the vibrations necessary for the descent of the catalyst particles, * at least one combustion zone in which is disposed at least one turn of the vibrating helical conveyor comprising at least one gas introduction pipe and at least one gas outlet pipe, * at least one chlorination zone in which is disposed at least one turn of the vibrating helical conveyor comprising at least one gas introduction pipe and at minus an outlet pipe gases.   11. Installation according to claim 10 comprising at least one calcination zone located below the combustion and chlorination zones in which is disposed at least one turn of the vibrating helical conveyor comprising at least one gas introduction pipe and at least one gas outlet line. 12. Installation according to claim 10 or 1il in which the zones of   combustion and chlorination are confused.