DE2315930A1 - PROCESS FOR REGENERATION OF A MASS CONTAINING CATALYTICALLY ACTIVE METALS AND SYSTEM FOR CARRYING OUT THE PROCESS - Google Patents

Description

Π, FV ♦ Wf U D-62 WIESBADEN March 27, 1973

DT. LJiCtQT Weber Postfa * 1327 v / pf

T "\ j« _1 ΠΙ- Γ / Ί C 'ff * Gustav-Freytag-Strasse 25

Uipl.-Fnys. Klaus Seiffert 9 q ι ς qq η * ^{(06121) 3727M}

PATENTANWÄLTE ^ «—- * ™ εντ

Series 1

L ¹ AIR LIQUIDE, SOCIETE ANONYME POUR L ¹ ETUDE ET L'EXPLOITATION DES PROCEDES GEORGESCLAUDE 75, Quai d'Orsay, 75007 Paris / Fankr.

and

ANTAR Pétroles DE L ATLANTIQUE ^1, h rue Leon Jost - ■ 75017 - Paris / France

PROCESS FOR THE REGENERATION OF CATALYTICALLY ACTIVE METALS CONTAINING MASS AND PLANT FOR CARRYING OUT THE PROCEDURE

Priority of March 32nd, 1972 in France, Registration no. EN 72 11. 526

The invention relates to a method and a system for the regeneration of a mass containing catalytically active metals or a catalytic mass to the subject. It relates in the same way to catalytic mass regenerated in this way and gases treated with the aid of these regenerated masses.

It is known to be involved in petrochemical techniques makes extensive use of masses containing catalytically active metals. In general, these are catalysts in the said cracking and reforming activities used, and their activity is gradually reduced in the

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Postal check: Frankfurt / Main 6763 Bank: Dresdner Bank AG, Wiesbaden, account no. 276807

History of their use because of carbon and tar deposits on the catalytic mass form and poison the catalyst.

In fact, the activity of the catalytic mass is reduced with the deposits produced, and it is therefore necessary to to regenerate this mass by making these deposits disappear, which is generally done through your burn creates. This incineration activity calls for numerous precautionary measures due to hazards posed by the introduction of combustion gases into caused a container enclosing the catalytic mass which, on the other hand, may contain certain amounts of gas that are capable of being explosive with the Combustion agents or oxygen carriers react, whereby this gas in the course of cracking or reforming operations can be produced

In the known regeneration processes, this is the catalytic one Containers or spaces enclosing mass initially v> n the gaseous atmosphere it contains by circulation large volumes of inert purging gas, generally nitrogen, or by filling or subsequent emptying by means of inert ones, for example consisting of nitrogen Gas freed, then one gives up, as any trace of the gas, by mixing with the combustion gas with the dangers lead or is suitable to lead the explosion

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the room is removed, dry air compressed into the purge gas on the bridge of the purge gas _? for example to a pressure of the order of 7 bar

Although we see so far satisfied are _t according to the above process to work, they are not fully satisfactory, because regeneration takes a relatively significant loss of time and requires significant of apparatus investment, such as Comp-ressoren, dryer, etc., the only work intermittently.

German Patent 1 006 562 from Sinclair Refining The Company specifically describes a method of regenerating a flatin-on-alumina catalyst that has carbonized by depositing coke on the catalyst particles in the reforming of petroleum hydrocarbons is deactivated or contaminated. The method described in the prior publication consists of the combustion of coal-like Material on the catalyst by making a gas mixture with inert gases and with oxygen in one Amount that is sufficient to maintain the combustion, but corresponds to a maximum of 1.5 vol .- $ oxygen, with the brings contaminated catalyst into contact, which is kept at 260 to 480 C and under a maximum of 35 kg / cm pressure is, while keeping the water vapor partial pressure of the exhaust gases below 50 mm of mercury and the combustion of the carbon-containing deposits continues until these are practically removed from the catalyst, after which

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the catalyst is kept at a temperature of 430 to 51 ° C in a dry atmosphere in which the partial pressure of the free oxygen is between O ₉ 2 and 3 atmospheres for at least half an hour, in order to convert the metallic platinum into its oxide form »

The present invention offers the advantage that it can leads to a reduction in the operating time, in particular due to the possibility of working at a higher pressure by going up to the operating pressure limit of the system and avoid the use of a compressor designed to uniformly mix the combustion agent to compress, leading to better heat exchange and greater adaptability or flexibility got.

The reduction in operating time is very significant economic gains. For every regeneration in a refinery you gain at least two production days. For someone who treats or transfers 10,000 tons per day Refinery, either from Arzew crude oil or light Arabian petroleum, expresses the reforming stoppage in a loss of reformed product (reformate) of θ tons for the Arzew property, or $ 8,460 per day, and 67Ο tons for the unbelievable Arab Incoming goods or $ 6,3Ο per day. For each regeneration, the savings in the refinery are at least

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I69OO dollars or I2060 dollars. With knowledge of the service life of a catalyst of about 5 years, 15 ^ 500 to 130,360 Gaining dollars, repatriating to barrels, the saving is $ 11 to $ 13. In the case of two regenerations the savings per barrel per day can reach $ 20 per year. The gains vary depending on the type of catalyst between $ 11 and $ 20 per barrel per day.

The type of regeneration according to the invention also allows a saving in investment in the construction of the refinery. For a refinery of 12,000 days Barrels regeneration method used so far _o mpressor vn 15OO m / h request a K., So an installation price of 120,000 dollars. The estimated cost of equipment in accordance with the invention, including the cost of nitrogen for 10 regenerations, is $ 5,000. The saving is thus $ 7OOOO.

The present invention relates to a method for regeneration by combustion of on a catalytic Mass deposits formed during operation, e.g. during cracking or reforming, during this time at least one gas, such as hydrogen, is generated, which is capable of forming an exploding mixture with the combustion gas used, this process consists in flushing the catalytic mass with it

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Using a circulating inert gas such as nitrogen, to effect, then, when this mass is practically freed of the gas which can form an exploding mixture with the combustion gas, the combustion agent in the Introduce purge gas, which is sent back to the catalytic «mass, and is characterized in that the combustion agent is introduced into the purge gas in the form of a combustion agent mixture obtained by mixing of the combustion agent with a portion of the purge gas that is derived from the purge flow.

According to one embodiment of the invention, the combustion agent mixture is introduced into the purge gas at a point which is arranged upstream of the point, where said part of the purge gas is diverted from the purge flow.

According to another embodiment of the invention are the means provided for the circulation of the purge gas are arranged upstream of the point where the said Part of the flushing gas is diverted from the flushing flow and downstream from the point of introduction of the combustion agent mixture into the purge gas.

According to another embodiment of the invention, the combustion agent mixture, which is in the purge gas, is introduced is, from gaseous oxygen and inert gas, preferably nitrogen, in proportions of the order of magnitude from 0 to 32 $ and preferably from 0 to 28 vol .- #.

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According to another embodiment of the invention lie the combustion agent / inert gas ratios and preferably the oxygen / nitrogen ratios the purge gas stream sent back to the catalytic mass to be regenerated is between 0.05 and 1% by volume and preferably between 0.1 and 0.6

According to another embodiment of the invention, the gaseous oxygen starting from the relaxed and gaseous oxygen obtained from an oxygen- source, e.g. a source of liquid oxygen.

According to another embodiment of the invention we d the Said part of the purge gas, which is derived from the purge flow, primarily in the formation of the combustion agent mixture relaxed.

According to another embodiment of the invention, the combustion agent mixture is given priority when it is introduced relaxed in the purge gas.

According to another embodiment of the present invention the catalytic mass preferably consists of one

Dimensions
inert / made of silicon oxide, aluminum oxide, high-alumina cement or other difficult-to-melt material. is formed, and contains a catalytically active metal, such as platinum, palladium, nickel, cobalt, etc.

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The present invention also relates to a plant to carry out the above procedure.

In particular, it relates to an installation for implementation a regeneration process by incineration of contained on at least one in at least one Raim tenen catalytic mass formed deposits, this plant having a main circuit for the recirculation the flushing gases in contact with the catalytic mass on this mass, circulating means, e.g. a compressor with one or more stages, which are arranged in this main circuit, a secondary circuit, which forms a loop or a shunt that is downstream at one point in the main circuit connects from the circulation means to a point upstream of these circulation means, and Expansion means, such as one or more valves, as well as supply means for a gaseous combustion agent, this expansion and Supply means are arranged in the loop.

According to a particular embodiment of the plant according to the invention, the supply means are for gaseous Combustion means connected to a source of combustion means by a conduit comprising means, e.g. Anti-return and means for relaxation and regulation arranged between this flap and the source

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the combustion engine throughput and, if necessary, to maintain it of the combustion agent in the gaseous state "

According to another particular embodiment of the invention are means for regulating the combustion agent flow rate as a function of the combustion agent content of the flowing gas in contact with the catalytic mass or as a puncture in the catalytic mass developed temperature provided.

The invention also relates to the regenerated material thus obtained catalytic mass and are also the gases treated with these regenerated masses.

Further advantages and features of _s Anwendurgpmöglichkeiten the vorlie constricting invention will become apparent from the following description taken in conjunction with the drawings.

The plant shown in Fig. 1 shows three catalytic circuits, each of which _{is embodied by a space 1 'f} 1 "and 1 ^111. Each of these circuits actually has a certain number of elements, such as heat exchangers, ovens, reactors, etc. for the sake of simplicity are not shown and also special lines 2 ', 2 "or 2 ^ffl ," which combine to form a common circuit 2. These catalytic circuits have in particular a catalytic mass which consists of a holder made of aluminum oxide on which $ 0.2 to $ 1 platinum and

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preferably 0.35 to 0.6 platinum is applied. -These catalytic masses are usually used for carrying out activities ₉ such as e.g. Cracking, reforming, etc. used.

Because the activity of these masses as a result of their slow poisoning due to the carbon that forms on their surface If deposits become too weak, it is necessary to do this Interrupt cracking or reforming activities, and then with their regeneration by burning the deposited Carbon to continue. Indeed, the presence of the hydrogen in the allows for the reforming to proceed or the cracking generated gases making this regeneration only when the atmosphere is catalytic Cycle is purified of hydrogen (or other gases that mix explosive with the combustion agent mixture can form), which this atmosphere can contain.

For this purpose, an inert circulating gas, such as nitrogen, or flushing gas (with approximately 40,000 Nm), which circulates in the common circuit 2 , is used. For example, means, not shown, are provided in this circuit in order to remove the gases drawn in during the flushing process, these means consisting, for example, of immersion bath columns, an absorption column or something else.

When the atmosphere of the catalytic cycle is practically entirely composed of hydrogen and other gases

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Combustion-type explosive mixtures can form, is purified and the purge gas stream (generally nitrogen), which circulates in the catalytic circuit, consists of practically pure inert gas, the valves 3 and h ₉ are arranged in the bypass 5, which is at the outlet of the compressor 6 is taken from the junction 7 and is returned at 8 on the suction side of the compressor 6, open. Means not shown allow the determination of the content of the gas flow leaving the catalytic circuits, whereby these means consist of classical analysis means «

The reservoir 9 contains liquid saturated substance under pressure. This oxygen is relaxed at 10, evaporated at 11 and then runs through valve 12 and regulator valve 13 » that in puncture of the throughput of the inert gas in the circuit

2 and in puncture the oxygen throughput in line lh is regulated (determined by the throughput meter 15). This oxygen is then introduced into the mixing device 16 in the bypass 5 between the valves

3 and k is arranged. A counter-return flap 17, a safety electric valve 18 and a bypass or shunt 19 can be provided in the line Ik between the regulator valve I3 and the mixing device 16. Control devices (not shown) allow the oxygen throughput entering the mixing device 16 to be regulated as a function of the oxygen content of the flushing gas flow, which is related to the catalytic mass.

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agitation is ^ with the regulating means not shown Means for determining the oxygen content of the purge gas are assigned.

The reservoir 9 for storing the liquid oxygen is a movable container _r, for example a known oxygen bottle, or any fixed volume connected to a production or supply system for liquid oxygen. If one wants to arrange a source of gaseous: ~ ati.a: r ~ rtoff, is it of course possible to use this oxygen? the system shown, the evaporation apparatus 1T, is deleted.

Obviously, it is possible to arrange in the catalytic mass (not shown, but consisting of known means such as thermocouples) means for determining the temperature that develops during the combustion of the coke, as well as for regulating the oxygen flow rate entering the mixing device 16 with the help of means not shown, but which also consist of known means, namely as a function of the temperature developed in the catalytic mass.

Beisgiel ^ i

An example of the system is given in the following: It is assumed that three catalytic circuits, which are represented by the spaces 1 \ "and 1 \" ^f \ "28 t one

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contain catalytic mass contaminated with carbon and which one wishes to regenerate through combustion. The plant is made with consideration for the exemption the gases (such as hydrogen) that mix explosively with the combustion agent, actually oxygen can form, swept over by a stream of nitrogen ^ or rinsed out.

The table below gives the results of those given in Times (in minutes) performed analyzes,

the

starting from a time O at which the temperature prevailing in the circuits is 36O C. Provision has been made to achieve a temperature of ^ 25 C, which, however, does not exceed 460 C. The suction pressure of the compressor 6 is between 8 and 10 bar and is 15 bar at the compressor outlet. The pressure of 15 bar has been chosen as an example and corresponds in fact to the pressure of the network ^{called "mean nitrogen pressure 11} " which generally flows through the furnaces with a view to liberating the hydrogen formed.

The results of the after the start at a time of 30 Analyzes carried out in minutes allow the determination of a clear progression of the combustion due to the increasing percentage of C0 "retained in the purge gas.

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TABEL

ο! ex? ί

Time in min. Temperature of the kata- ■ 420 ι t Stop 0. of regeneration Analysis in Io Co ₂ ¹ ■ 53 analysis at the exit 1- Cp ₂ ί ,, analysis at the exit ! 52 lytic circulation the loop 56 catalytic circuit 1 ' catal. District 1 »
i> co ! 55.5 ί Θ, (thermocouple) ia ° C % O ₂ ^{/ 0 U} 2 \ Β 'ν ίο O ₂ I.
ί 59.5 0 360 4oo '■■ .... ί «; '
Ö !
! 30th 360 440 8th , ! Φ 62.5 | 50 380 r 460 7.5 οΓ20, 5 64.5 ^! 60 450 17.5 9.5 65 ' 1 20 4oo 13.5 p32 165 26th 17th S37.5 '' · 175 380 15.5 23.5 >, 44.5 ί 210 I. 17th 26th 0 48 90 f 285 15th 0 345 24 0 375 : ■ 390 o, 5 420 o, 5 46ο ο, 5 505 3 525 4.5. 540 560 1 585 0 630 ■ · '· ■' " 0 770 17th 790 1'4.5 ⁸ 30 i ^
St. end

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Despite this combustion, the temperature stabilizes quickly to about 400 ° C.

After 210 minutes, the analysis shows that the burn was occurring practically completed in the catalytic cycle 1 is. So you switch the catalytic cycle 1 ' and immediately notices an at least good combustion, which means that the supply of oxygen is stopped 5 ^ 0 minutes because of the increasing accumulation of oxygen from the gas passing through the ovens.

After 77O minutes (i.e. after 12 hours and 5 ° minutes) the addition of oxygen is resumed, the regeneration of the catalytic circuits 1 and 1 · being completed is.

In order to continue with this regeneration under the conditions shown in the table, 5320 kg of oxygen were necessary; the duration of the burn is 2 hours.

In fact, the use of oxygen according to the invention, which is introduced into the medium-pressure nitrogen network which flows through these catalytic circuits, has the following advantages

- Reduction of the operating time, this reduction resulting from the fact that one

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at a pressure of 15 bar above the pressure of J Bar used up to then * »

- Improvement of the heat exchange due to the fact that a larger amount of gas flows through the furnaces; it actually runs kOOQQ Nm / h-

instead of 20000 Nm / h roughly hindurctij jvobel (the latter) in the known systems strömeii,

- it is possible to avoid a help! »compressor,

- The formation of crystals in the catalytic mass is prevented.

Example_2

A second regeneration is created in the plant according to FIG. 2. This plant has reactors 111, 112 and. and ovens 111 ', 112' and 113 '. The naphtha feed to be reformed is introduced into the plant through line \ Η , passes through heat exchanger 115, then flows through line 116, is introduced into furnace 111, then into reactor 111, furnace 112 and reactor 112, furnace 113 * and reactor 113 treated, the fluid leave the latter reactor below through line 11? » circulate in the heat exchanger 115 »flow through the partial condenser 118 and are introduced into the separator or bottle balloon (also flash flask) 119. A fraction of the feed goes through the distillation 120, the hydrogen is ^{removed in the upper © 11} part of the separator through the recycling line 121, the

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passes through compressor 122 and 123 and recombines at 114; a hydrogen fraction goes off at the discharge 124. The oxygen circuit is connected at 122 through 125, with a reserve of pure O ₀ in 126, the oxygen is introduced through the line 127 and, after passing through the valve 128 at the apex or top of the reactor 113 Downstream of each reactor distributed at 129 and 130 for reactor 111, at 131 and 132 for reactor 112 and at 133 and 134 for reactor 113.

The system is put under a nitrogen suction pressure of 8 to 10 bar. Regeneration is started in reactor 113. After the combustion of the carbonaceous deposits in this reactor has been completed, combustion is initiated in reactor 111 and finally in reactor 112. The regeneration is initiated after the temperature in reactor II3 has reached 425 ° C., whereby this should not exceed 450 ° C. The oxygen circuit is in connection with a reserve on a commercial vehicle under a pressure of 15 bar. At first 0.1 ^ oxygen is introduced into the circuit, then the oxygen content is increased, but without 0.5 $ oxygen in the circuit exceed. In the regeneration of the two other reactors O ₉ 5 $ oxygen is introduced ₅ and a second and a third combustion phase is observed in reactor 113 · At 375 C the re-

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generation ended in the three reactors,

Figures 3 »^ and 5 show the respective different combustion phases in the reactors 113» l ^ ¹ and 112. The time in hours (t) is on the abscissa and the temperature in C plotted Q aif the ordinate. In FIG. 3, curve 1 corresponds to temperature recording 133 upstream of reactor 113 and curve 2 corresponds to temperature recording 134 downstream of said reactor 113.

The regeneration began at 10 hours and is practically over between 17 and 18 hours. A weaker second combustion phase between 21 hours and 6 hours and 30 minutes is observed in reactor 113; Then comes a third combustion phase of very reduced duration and the known chlorination phase. The oxygen throughputs or flow rates are displayed in Nm / h and correspond to 100, 200 and 300 Nm ³ / **

For reactor 111, curve 3 corresponds to the temperature extraction at 129 upstream and curve k corresponds to the temperature extraction downstream from reactor 111. For reactor 112, curve 5 corresponds to temperature extraction 131 upstream and curve 6 corresponds to temperature extraction 132 downstream of reactor 112.

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FIG. 6 gives the percentages of fuel in the closed loop or input loop, the percentages of oxygen entering the reactor 113 "and the percentages of CO ₀ entering the reactor 113 *

The regeneration time - in hours (t) - is on the abscissa and the percentages 0 and C0 "are up, respectively plotted on the ordinate.

Curve 7 shows the oxygen percentages at the inlet of the reactor, curve 8 the percentages of CO- at the inlet of the same reactor and curve ₀ <3 the contents of O 0 in the closed input circuit or in the input loop.

Of course, the present invention is not limited to the embodiment described, and it numerous changes accessible to those skilled in the art can be made without changing the thoughts of Invention leaves. So it is possible that the number of catalytic cycles is not limited to 3 and that the nitrogen used comes from somewhere and consists in particular of gaseous nitrogen that is available can. It should not go unmentioned that it is possible, according to known techniques, to be substantially variable Introduce quantities of nitrogen into or out of the system to leave if the need arises,

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to allow a certain amount of nitrogen to escape or to introduce an additional amount of nitrogen into the system. - -

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Claims (12)

Claims 1. Process for regeneration by combustion of deposits formed on a catalytic mass in the course of operation »eg during cracking or reforming, during which at least one gas, such as hydrogen, is generated; which is suitable for forming an explosive mixture with the combustion gas used, this process consisting in ₃ flushing the catalytic mass with the aid of an inert gas flow, such as nitrogen, when this mass is practically freed from the gas, capable of forming an exploding mixture with the combustion agent, introducing the combustion agent into the purge gas stream sent back to the catalytic mass, characterized in that the combustion agent is introduced into the purge gas in the form of a combustion agent mixture obtained by mixing the combustion agent with receives a portion of the purge gas that is derived from the purge flow. 2. The method according to claim 1, characterized in that the combustion agent mixture in the purge gas at a Digit is entered, the upstream of the one Place is arranged where said part of the purge gas is derived from the purge flow. 309841/109 1 3. Method according to claim 1 or 2, characterized in that that the means provided for the circulation of the flushing gas upstream of that point are arranged where said part of the purge gas from Purge flow is derived, as well as downstream of the .Stelle of the introduction of the combustion agent mixture in the purge gas in. 4. The method according to any one of claims 1 to 3 # thereby characterized in that said portion of the purge gas diverted from the purge stream is preferably upon formation the combustion agent mixture is relaxed. 5. The method according to one of claims 1 to h _t, characterized in that the mixture is preferably depressurized when it is introduced into the flushing gas. 6. The method according to any one of claims 1 to 5 »thereby characterized in that the combustion agent mixture which is introduced into the purge gas consists of gaseous acid I " Substance and inert gas is formed, preferably from nitrogen in proportions on the order of O to 32 volume percent and preferably from 0 to 28 volume percent. 7. Method according to one of Claims 1 to 6, characterized in that the proportions of combustion agent / inert Gas, and especially the proportions 308841/109 1 - 23 - - ■ 23 - Oxygen / nitrogen, des on the to be regenerated catalytic mass returned purge gas stream to 0.05 to 1 volume and preferably 0.1 to Amount to $ 0.6 in volume. 8. The method according to any one of claims 1 to 7 »thereby characterized in that the gaseous oxygen is obtained starting from relaxed and gaseous oxygenj that from a source of oxygen, e.g. a source of liquid oxygen. 9 · Process, characterized in that the catalytically ^ Mass consists of an inert mass made of silicon oxide, aluminum oxide, calcium aluminate cement or other heavy fusible material is formed, and contains a catalytically active metal, such as platinum, palladium, nickel, Cobalt and the like. 10. Plant for the implementation of a regeneration process by incineration of deposits that are based on at least a catalytic mass are formed in at least one space, with a main circuit for the recirculation of the itself purge gases in contact with the catalytic mass on this mass, circulating means, such as a compressor with one or more stages arranged in the main circuit, characterized in that the System has a secondary circuit that forms a loop or a shunt that is at one point 3 0 9841/1091 - 24 - 231593Q of the main circuit downstream of the urea rolling agents to a point upstream from these circulating means connects, and has expansion means, such as one or more valves, as well as poisoning means for gaseous combustion means, the expansion and supply means being arranged in the loop are. 11. Plant according to claim 10, characterized in that the failure agents for gaseous combustion media connected to a source of incinerator through a conduit having means such as counter-return flaps, and interposed between this flap and the source Has means for expanding and regulating the combustion agent throughput and possibly for maintaining the combustion agent in the gaseous state. 12. Plant according to claims 10 or 11, characterized in that that the means for regulating the combustion medium throughput as a function of the combustion agent content of the gas flow in contact with the catalytic mass are provided. 13 · Plant according to claim 10 or 11 _8, characterized in that means are provided for regulating the combustion agent throughput as a function of the temperature developed in the catalytic mass. 3 0 9 8 4-1 / 1091 ". ■ Blank page