JPH05505407A - Method and apparatus for steam cracking hydrocarbons in fluid phase - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] Method and apparatus for steam crabbing hydrocarbons in a fluid phase The invention relates to olefins, particularly olefins of 2 to 4 carbon atoms, butadiene, and Monoaromatic compounds such as benzene, or branched aromatics such as toluene and xylene. For the production of aromatic compounds, petroleum hydrocarbon fractions are transferred at high temperatures in a fluidized phase of heat-retentive particles. The present invention relates to a steam crabbing method and an apparatus for carrying out the method.

Hydrocarbon crabking methods are commonly used in the petroleum or quasi-petroleum industry. be done. These methods break down hydrocarbon molecules into smaller molecules by increasing the temperature. It is divided into children. There are two crabking methods, which use only the effect of temperature. Thermal cranking or catalytic clubking methods that use the active sites of the catalyst. Ru.

In conventional thermal cracking plants, the hydrocarbon charge is fed into a tubular reactor. Heats up gradually. Thermal cracking reactions occur primarily in the tube section receiving the maximum heat flux. The temperature of this part depends on the nature of the cracking hydrocarbon as described below. Determined by

- So-called visbreaking method, in which only the heaviest molecules are split into lighter molecules In some cases, the crabbing temperature is in the range of 450° to 600°C.

- The molecule to be thermally cracked is a light gas such as gasoline or liquefied petroleum gas (LPG). molecule and also tends to produce light olefins and monoaromatics. In this case, the required temperature is much higher depending on the type of charge being cracked and is generally within the range of 780 to 850°C, subject to process operating conditions and associated heating energy. -Limited by the complexity of the generator's functionality.

Achieving and maintaining the required temperature level requires undesirable This becomes more difficult as the thick coke gradually builds up and the heat flux is restricted. moreover , a bulkhead temperature higher than the reaction temperature will result in coke formation and rubber mold and acetylene leading to the formation of deterioration products of the carbon compound type. Coke reduces heat exchangeability . Coke increases the loss of charge inside the reaction tube and also increases the temperature of the tube wall, This creates excessive mechanical stress and therefore carbonization inside the thermal cracking plant. Reduces hydrogen charge conversion and eliminates plant shutdowns for periodic coke removal operations. need to be stopped. As a result, on the one hand, coke removal work can be carried out during operation. The process must be modular so that the equipment processed on the other hand The contents must be "clean" enough that the coking cycle is not too short. Must be. In practice, these charges include LPG, gasoline, and other suitable It is limited to some gas oils that have been treated with or without hydrogenation.

Furthermore, the heat transfer action in the reaction tube is not instantaneous, and the thermal clubking reaction is extremely absorbing. It is a thermal reaction. Therefore, temperature regulation and maintenance problems as well as selectivity problems are solved. Have difficulty.

In order to solve these problems and carry out thermal clubking of hydrocarbons, It has been proposed to use fluidized bed technology. for example, - U.S. Patent No. 3,074,878 (Ethane) and European Patent Application No. 26,674 (Stone) is supplied by the combustion of coke deposited on heat retaining particles The thermal A fluidized bed tubular reactor with quantity-retaining particles descending is used.

U.S. Pat. No. 4,427,538 (Engelnod) discloses inert heat-retaining grains. The rising fluid phase reaction of the A tubular reactor is used to carry out the removal of the heaviest hydrocarbons.

However, none of these methods can handle LPG, gasoline, or even highly polluted residues. Synthesis of light olefins and monoaromatic compounds of various hydrocarbon fractions such as distillate feeds Time conversion cannot be carried out under satisfactory industrial conditions.

In fact, light/grafine hydrocarbons such as butane, propane, and especially ethane and for thermal clubking of petroleum fractions such as gasoline, naphtha and gas oil. , the reaction temperature is brought to a very high level on the order of 750-850°C for a very short but severe It must be held for a very controlled amount of time. Residence time variation in this temperature range Without constant precise control, the olefin molecules formed during the conversion process can polymerize. inhibits the overall selectivity of the reaction. By the way, until now, the reaction outflow from heat retention particles Separation systems used to separate liquids generally provide a sufficiently rapid separation of the effluent. Since separation and rapid cooling cannot be carried out, some of the molecules formed may react and polymerize. There is a possibility that it will continue.

As a result, the hydrocarbons in the separation stripping zone and between this zone and the fractionation zone There is always a risk of blockage and talin formation in the primary effluent conduit.

Furthermore, because of the highly endothermic nature of the thermal conversion by steam crabbing, it is also possible to A significant amount of water vapor is placed in the reaction zone to reduce partial pressure and minimize coke formation. maintains the gas phase at the desired temperature for thermal cracking because it is injected into the requires the instantaneous application of a very large amount of heat. light hydrocarbon fraction For steam cracking into fins and monoaromatics, heat retaining particles The amount of coke deposited on top is completely insufficient to guarantee thermal equilibrium of the system , and would require systematic addition of external energy.

Finally, these thermal equilibria and temperature levels that must be achieved are very important for heat-retentive particles. Apply high temperature to. By the way, the technology partially related to the metallurgy of this plant Because of the difficulties in achieving can be done.

The present invention enables the production of petroleum hydrocarbon fractions under strictly specified fluidization conditions, temperature conditions and times. The above-mentioned The distillate is converted into olefins such as ethylene, propylene and butene, butadiene and By providing a method for high temperature steam Krasoking conversion to monoaromatic compounds , to solve the above problems.

The present invention also provides light olefins by cracking the fraction introduced into the reactor. Produces satisfactory conversions with high selectivity for fins, butadiene and monoaromatics. It's in the village.

Furthermore, the present invention enables efficient control of the polymerization reaction of reaction products.

Finally, the present invention requires only a small amount of coke, but enough to satisfy the heat balance of the plant. The aim is to manufacture a sufficient amount.

Therefore, the object of the present invention is, on the one hand, to avoid contamination by metals and to maintain temperatures below about 400°C. at least one light hydrocarbon fraction having a boiling point of, on the other hand, essentially with said heavier hydrocarbon charge consisting of compounds having a boiling point above about 400°C. Qualitatively due to high temperature steam crabbing in the presence of a dilute fluidized phase of heat-retaining particles A conversion process, the process comprising: a continuous upflow or downflow tubular reactor; The fraction and then the charge are subjected to a catalytic or contacting non-catalytic particles and at least 90% of said particles with said hydrocarbon. a separation step for separating the raw effluent from said separated grains; The particles are then preferably regenerated by reaction of coke deposited on these particles. The separated hydrocarbon stream is then recycled through the continuous reactor at a higher temperature. In the steam crabking method, the effluent is recovered by distillation in the fractionation stage. wherein the method includes a step between the particle-hydrocarbon effluent separation stage and the distillation stage. injecting at least a portion of said heavy hydrocarbon charge into said distillation process; recycling at least a portion of the residue of the fractionation step into a downstream section of the reactor. A process for converting hydrocarbons by steam cracking comprising steps.

Uncontaminated light hydrocarbon fractions distilled at temperatures below 400°C are desirable. light paraffinic hydrocarbons such as ethane, propane and butane, and gas Heavy hydrocarbons such as phosphorus, naphtha and gas oil, as well as paraffin or sludge. have a higher boiling point but are strongly parasitic, such as waxes or hydrocarbon cycles. Selected from a group consisting of two or three fractions of the finic or naphthenic type. child These hydrocarbon fractions are used in atmospheric distillation plants, visbreaking plants, Rock cracking plant, oil production plant or olefin oligomerization plan from various refining plants such as Obtained from effluent. These various fractions can be used alone or with water vapor and/or water vapor. can be injected with other fluidizing gases such as hydrogen and light gases. .

Preferably, according to a particularly preferred embodiment, the steam crab king gradually The presence of water vapor and/or gaseous fluids in a multi-zone continuous reactor inject a number of separate fractions, the leading fraction always having a lower boiling point than the trailing fraction. This is how it is implemented. In practice, such a temperature distribution optimizes the selectivity of the reaction. It is particularly effective for For example, sequentially, a first fraction containing primarily ethane, Then, in some cases, propane and butane are added, followed by light gasoline in the liquid phase. distillate, then optionally naphtha or gas oil, and finally boiling above about 400°C. A heavy hydrocarbon charge with spots can be injected. The last heavy hydrocarbon is Atmospheric or vacuum distillation residues, deasphalted pitch, catalyst slurries, or Selected from the group consisting of synthetic hydrocarbons. These charges are therefore 75 having a boiling point of 0°C or higher and a density within the range of 0 to 25° API A very heavy charge containing hydrocarbons can be produced.

The injection rates of these heavy hydrocarbon charges are determined by the desired temperature profile and heat balance needs. Accordingly, it is desirable that the amount be 0.25 to 4 times the amount of light distillate injected upstream. .

Gradually, heavier fractions are injected in sequence, such as ethane or LPG (liquefied petroleum gas). ), then gasoline or gas oil, and finally distillation residue type heavy gas downstream of the continuous reactor. In the sophisticated structure of the continuous reactor of the present invention with an injector for injecting the quality charge, In other words, a continuous reactor has multiple separate reaction zones that are sequentially moderated. conditions (temperature, contact time with heat-retaining particles, and catalytic activity of these heat-retaining particles) and reduction conditions such as the ratio of the flow rate of heat-retaining particles to the flow rate of hydrocarbons). and the nature of the feedstock to be treated and the desired product. Do it like this For example, in the heat retention particle injection section where the temperature is the highest (on the order of 850 to 950 °C) in the presence of water vapor in the most upstream zone of a continuous reactor. by steam crabbing, and then by utilizing the temperature drop caused by the endothermic reaction. Propane or butane at temperatures on the order of 800-900°C into the following areas: Inject the distillate and then inject an intermediate hydrocarbon such as a gas oil type fraction or a light gasoline fraction. Inject the raw distillate. Finally, the lowest temperature obtained as a result of such an endothermic reaction In the area, the heaviest charge is crabbed and the heaviest of the steam crabking reaction is All or all of the heavy residues are removed in the downstream part of the reactor under conditions most suited to their properties. can club some of them.

In many studies in this field, the applicant has identified the trailing injection zone with respect to the leading zone. The reaction time in the reactor can be reduced by using it as a quench area. The reaction temperature conditions can be controlled relatively easily, but the separation of heat-retentive particles - Sudrippin A different situation was observed in the reaction area just before the monitoring area. In fact, steaming At the extremely high temperature levels always required for air crabbing, The desired olefin is produced while minimizing the formation of coke or heavy products due to polymerization. Separation of hydrocarbon gas and solids must be almost instantaneous in order to preserve the yield of fins. There must be.

Therefore, fluidized bed steam crabbing has been limited to date by the following dilemmas: was.

- Pallistic separation systems, often consisting of cyclones, are efficient case. In this case, the separation time is optimized for yield and also for coke formation and acetylene formation. too long to prevent contaminant formation.

If the one-separation system is instantaneous but its efficiency is low.

In this case, the entrainment of hydrocarbons into the regeneration zone may involve excessive losses and or entrain excessive amounts of solid particles, especially fine particles, with the gas effluent, which can be removed from the distillate. Fractional distillation is very costly, making effective use of these distillates difficult; Also, when solid particles have a certain degree of catalytic activity, undesirable secondary reactions may occur. There is a risk of

The present invention provides a guide for directing the reaction effluent of a steam clubking plant to its fractionation zone. It seeks to solve the problems associated with the formation of coke and degradation products in the pipes. Ru.

In fact, hydrocarbon effluent from a conventional steam crabbing plant was separated by distillation. These effluent temperatures must be reduced very strongly and rapidly in order to be able to be contained. In addition, below the “dew point” of these effluents (i.e., the temperature at which the heaviest fraction condenses), The temperature must be obtained at the inlet of the fractionation column. By the way, at this temperature During the rapid decline, the heaviest mass produced by the steam crabking reaction, as is known Compounds tend to deposit on the walls of these conduits and therefore Incurs the cost of periodically shutting down the steam crab king plant to remove the residue. .

The invention also provides that after the separation step of at least 90% of the particles from the hydrocarbons, the The bulk of the heaviest charge required for thermal equilibrium of the steam crabking reaction before the fractionation step The above-mentioned problems can be solved by injecting .

This special charge injection mode is suitable for the temperature conditions of the steam crabking reaction for the following reasons: It allows for complete control over the subject and time conditions.

The rapid cooling effect necessary for instantaneous termination of a thermal reaction is preheated by the thermal reaction itself. This is guaranteed by the injection of the same charge. This is due to the dilution effect of the condensed liquid effluent. The coke particles work together to remove all coke precursors present in the effluent from the still liquid stone. It can be effectively inactivated by dissolving it in the oil charge (such A rapid cooling effect can be achieved in some cases by passing the hydrocarbons through a heat exchanger. fractional distillation by freshly injecting water, steam or other hydrocarbon fractions. (can be completed before the stage).

0.01 to 10%, preferably 0.05 to 5%, entrained in the effluent of one reactor % of heat retention particles constantly clean the wall surface to prevent tarinka formation and keep the conduit clean. It can absorb the rubber formed inside.

- Circulating the distillation residue into the downstream part of the reactor is important for maintaining the thermal balance of the plant and Olefins and heavy charges that have not previously been used in steam cracking processes It not only guarantees the conversion to aromatics and monoaromatics, but also the most It becomes possible to consume quality products.

In this case, the evaporation is almost instantaneous and homogeneous, and the recycle is heated to a temperature close to its boiling point. Heated and therefore in excellent conditions for very selective love-king. It will be done.

Furthermore, since all the entrained heat retention particles are circulated, in this case, the number of circulating particles is It is possible to reduce the efficiency of separating this heat-retaining particle from the gaseous effluent without excessive losses. It is possible to increase the separation speed.

According to a particularly preferred embodiment of the invention, as known per se (European Patent No. 3 12,428) By injecting the charge in liquid form, the heaviest hydrocarbon almost instantaneous heat exchange between the input and the steam Crab King reaction effluent can be ensured. can. The quality of this heat exchange is related to the heat exchange surface between the liquid and the gas, so the injector sprays a droplet charge with a diameter of less than 200 microns, preferably less than 100 microns. Constructed to fog. Said injector preferably injects a certain amount with the charge. It is desirable to have a mixing chamber for introducing water or steam or other petroleum fractions. Delicious. Furthermore, considerable amounts of fractionation residues can be introduced together with the charge.

Furthermore, the hydrocarbon temperature entering the fractionation zone is As a result of the dissolution of the Steam Crab King effluent in the This rapid cooling effect is optimal.

Due to the heat exchange that occurs in this way, the hydrocarbon temperature is lower than 0.3 seconds, preferably It is cooled to a temperature within the range of 300 to 450°C in less than 0.1 seconds.

More specifically, the hydrocarbon charge entering the fractionation zone is rated at its "bubble point" ( In other words, the temperature is preferably 100°C or lower than the temperature at which the first gas bubbles are formed in the liquid state. Preferably, it has a low temperature of 50°C or less.

Further, according to a preferred embodiment of the present invention, the saturated hydrocarbons produced during the reaction are The yield of olefins and monoaromatics can be increased by recycling Ru.

For this purpose, these olefins must be extracted from C2, C3, C4 fractions and other products. The saturated hydrocarbons are separated and recycled into the corresponding injection zone of the upstream part of the reactor. As a ring modification, for example, a mixture of ethane and ethylene leaving the fractionation zone can be used. and the mixture was placed in an ethylene trimerization reactor or oven of the type known in the prior art. into the ligomerization reactor (European Patent No. 12.685, No. 24°971, No. 215,609 or U.S. Pat. No. 4,605.807); The following items can be collected after depletion.

- on the one hand, unreacted ethane, which according to the invention is in the upstream part of the reaction zone; - On the other hand, the light gas resulting from said oligomerization process is recycled to the inlet. phosphorus, this gasoline works more mildly, sometimes with other gasolines recycled into the steam cracking section to produce e.g. propylene and butene. can be done.

Yet another advantage of the invention is that steam crabbing is performed in the upstream section of the reactor. The hydrogen naturally generated during the reaction reacts under the reaction conditions in the downstream part of the reactor and The selectivity of the runt effluent to useful and stable products can be improved.

Coke deposits resulting from thermal cracking or catalytic clubking, as previously discussed The upstream part of the tubular reactor must be kept to a minimum for economical reasons. and the downstream part must be sufficient to guarantee the heat balance (otherwise If so, heat balance can be guaranteed by introducing additive fuel into the regenerator. ). Also preferably at least 50%, preferably 80% by weight of the heavy charge. must have a boiling temperature of about 400°C or higher. This value of approximately 400℃ is Although it is qualitatively related to the fractionation point of the distillation residue, this value is of course It can vary between 300 and 550°C within the spirit.

These charges include vacuum treated gas oil, topped or topped crude oil, and atmospheric or vacuum distillation residues, pitch, beer, etc. Tummen emulsion, aromatic extract, catalyst slurry or synthetic or used oil I can give you. These charges can be used for preliminary purposes, e.g. by hydrogenation, if necessary. can be processed. These charges are particularly suitable for boiling at 750°C or higher. contains a fraction with a point and also has a high content of ff1 (10% or (more than this) may be indicated. These charges are diluted with lighter fractions undiluted or diluted, and generally between 160 and 220°C (at the beginning of fractional distillation) and between 320 and 38°C. LCO (r light cycle oil) with a boiling interval within the range of 0°C (end of fractional distillation) j), circulating heavy oil, i.e. 300-380°C (initial stage of fractional distillation), especially 460-500°C HCO (r heavy cycle oil) with a boiling interval within the range of °C (end of fractionation) ), or catalyst residues (slurries) where most of the fraction is distilled below 500°C. can contain recycled hydrocarbon fractions that have already undergone crabking treatment. Ru. According to a preferred embodiment of the invention, the charge, when in contact with hot solid particles, Generally, the temperature range is 100°C to 400°C, preferably or preheated to a temperature near the bubble point.

In order to carry out the method of the invention, materials such as kaolin or silicate microspheres are used. Inert heat retention particles known per se can be used. Also Catalyst Club King Any type of capable catalyst can also be used. Particularly desirable catalysts are It consists of a catalyst with a pore structure, and hydrocarbon molecules are brought into contact with the active sites of these pores. Ru. In this category there are especially silicates or aluminosilicates. seed various metal oxides and their combinations, especially silica, alumina, magnesia, and on a carrier containing a combination of these substances and a mixture of said oxide and clay. Catalysts containing stable zeolites are commercially available. Of course, the catalyst composition may contain one or more reactants that facilitate any of the steps. subordinate Therefore, the catalyst can contain reactants that promote coke combustion during regeneration. Alternatively, if aromatic products are the primary objective, aromatic cyclization of olefins or or a reactant that promotes the reverse reaction.

The operating temperature and pressure are high (generally 0.3 to 5 kg/Cm2) and the charcoal in the reaction zone is Hydrogen hydrogen retention time is short (on the order of several 1/100 to several 1/10 of a second), and Due to the rapid cooling and circulation conditions of the charge to be steam cracked, the implementation of the process of the invention is The application requires a few special measures, which form part of the invention.

Therefore, the present invention also provides, on the one hand, at least one light hydrocarbon fraction having, on the other hand, essentially about 40 essentially with said heavier hydrocarbon charge consisting of compounds with a boiling point above 0°C. Conversion plan by high-temperature steam cracking in the presence of a fluidized bed of heat-retentive particles The plant is configured to convert the fraction and the feed into a catalytic or non-catalytic an upflow or downflow tubular continuous reactor in contact with the particles; and at least one of said particles. Particularly pallitic means of separating said hydrocarbon effluent from said hydrocarbon effluent by 90%; means for stripping the separated particles and then removing the coat deposited on these particles. regeneration means under combustion conditions using air or water vapor, and the regenerated particles. means for feeding said continuous reactor and also means for fractionating the hydrocarbon effluent by distillation; a steam club king plant comprising: means for injecting a portion of the heavy hydrocarbon charge into the effluent at the on the other hand at least part of the distillation residue in liquid form but at a temperature close to its boiling point; and means for circulating and injecting a portion of the hydrocarbon into a downstream portion of the reactor. It concerns the Steam Crab King Plant.

The feedstock is circulated into the downstream part of the reactor as well as the injector into the effluent. The fractionation residue injector is designed to reduce the charge below 200 microns, preferably 100 microns. It is configured to atomize in the form of droplets with a diameter of less than a kilometer. This device is designed to circulate heat Preferably large diameter necks to limit as much as possible wear problems due to volume retention particles. type Venturi tube (see European Patent No. 312.428).

The invention also provides for certain types of A type of steam Crab King effluent separator can be utilized. Especially when the reactor is When operating in rising mode (“riser”), the heat Quantity retention particles have high speed (20-200m/S% preferably 40-100m/s) In some cases, it is possible to use a simple centrifugal separator. It will be possible. In this way the use of typically expensive cyclone equipment is avoided. Ru.

Similarly, when the reactor is operated in descending mode (“dropper”), heat-retaining particles is collected in the casing at the bottom of the dropper, where it can be used for simple paristic production. After separating the heat retaining particles from the steam crabking effluent in a It will be done.

The present invention will be described below with reference to embodiments shown in the drawings. It is not limited.

Figure 1 shows a rising group or “riser” and a single heat-retaining particle height specifically for catalytic regeneration. The present invention is applied to a fluidized bed steam cracking assembly including a hot regeneration chamber. 1 is a diagram showing an example, in which a pallitic separation device is The station is equipped with a simple pallitic centrifuge and Figures 2 and 3 are essentially steam crackers with descending reaction zones ("droppers"). 1 shows an embodiment of the invention for a booking assembly;

The rising fluid phase steam cracking apparatus shown in FIG. It includes a reaction column 1 called "riser". This riser is used, for example, to open and close valve 3. A quantity of regenerated heat retaining particles determined by line 2 is supplied to the base. It will be done. The regeneration particles diffuse the steam or other suitable gas stream coming from line 4. It is fluidized by injecting it into the base of the riser by the user 5.

In this case, the first line 6 is filled with saturated light gas such as ethane by the injection diffuser 7. into the upstream part of the reactor. Next, the propane fraction or butane fraction or a mixture of these fractions is likewise injected from line 8 by diffuser 9. be done. Similarly, gasoline or gas oil fraction is supplied by line 10 and It is evaporated by the fuser 11. Steam coming from fractionation zone 12 through line 14 The charge consisting of distillate residue is optionally a fresh feed charge coming from line 40. The moment the residue is mixed with the It is introduced at temperatures close to the bubble point of the residue to facilitate uniform evaporation.

The reaction column 1 opens at its apex into a casing 15, which casing 15 Concentric to the reaction column and in this casing 15, on the one hand the palistor Separation of the reaction effluent and heat retention particles is carried out by a block separator 16, and other In one step, stripping of the coked particles is carried out. hydrocarbon stream Effluent is drained from the centrifugal system 16 by a drain line 17, which 17 into which the cold charge coming from line 18 is injected by injector 19 and On the other hand, at least 90% of the heat retention particles descend toward the bottom of the casing 15. , at the bottom of which a line 20 carries a stripping gas, typically water vapor, to the case. Diffusers 21 regularly arranged at the bottom of the thing 15 are supplied.

The quenching effect of the effluent of the steam crabking reaction causes a fresh charge in the discharge line 17. This quenching effect is caused by the direct contact of the droplets with the effluent, and this quenching effect occurs in the fractionation zone 12. The residue of the distillation carried out in the tank is circulated by line 50 and injected. will be further strengthened. The distillation residue is cooled by passing it through a heat exchanger 51. The heat thus recovered is used to form steam for the entire plant. and there is no need to perform additional quenching as in prior art methods. Furthermore, the reaction The presence of small amounts of solid heat-retaining particles in the vessel effluent allows efficient cleaning of the side walls. Not only can it be applied, but it also serves as a means for adsorbing rubber precursors and coke deposits.

Also, for this reason, by injecting particles from line 53, particles in line 17 are The content can be changed.

The heat retention particles stripped at the base of the casing 15 are passed through the conduit 23. It discharges into a regenerator 22, on which conduit 23 a control valve 24 is arranged. This diagram 1, the regenerator 22 converts the coke deposited on the heat retention particles into oxygen or water vapor It has only a single area that burns in the presence of air. This regeneration process Most of the heat generated by the combustion of The reaction is carried out to reach the high temperatures required for the reaction at a temperature. In this way, the diffuse By means of air injected into the bottom of the regenerator by line 25 reaching laser 26, Coke deposited on the heat retaining particles is removed.

In some cases, additional fuel may be injected to adjust the temperature to the desired level. Wear. Regeneration gas is separated from the heat retaining particles entrained in the cyclone 27, The regeneration gas is removed from line 28 while the regenerated hot heat retaining particles are removed from the regenerator. through conduit 2 to elevator or riser 1.

In addition, after quenching by injection of the charge in 19, the reaction effluent and the introduced from 19 The charged charge is introduced into the fractionator 12 via line 17. This fractionator is , - separation of light gas by line 29, which gas is treated in another fractionator. and, as is known, specifically ethane from line 30 and propane from line 31. Separate from

A gasoline fraction is separated through a line 36, and the boiling point of this gasoline fraction is generally It is within the range of 200 to 220°C from fraction C5.

From one line 37, a gas oil type fraction is separated, whose boiling point range is generally 160-22 It is within the range of 0°C (initial stage of fractional distillation) to 320 to 400°C (final stage of fractional distillation).

- Finally, from line 14, a portion of the distillation residue fraction is separated off, which fraction is charged The heaviest products from the reaction effluent and a relatively large amount of heat retaining particles are containing (this residue is in the 300-550'C range, typically on the order of 400'C) boiling point).

According to the invention, therefore, a portion of this residue is injected into the steam crabking reactor. be done. In some cases, after passing through the heat exchanger 51 and recovering the heat, the line 5 mixed with the steam cracking charge through 0 and circulated for quenching, or is extracted from the device through drain line 52.

In addition, the ethane, propane, and gasoline fractions coming out of this fractionator are each line 3. 0.31.36, then sent to the reaction site through lines 6.8 and 10 and vaporized. C2 caused by air cracking. Ca olefin is in line 33. separated by 34.

The essential advantage of this fluid phase steam cracking device is that the temperature profile in the reaction zone 1 It is possible to selectively crab many petroleum fractions by making good use of oil. Ru.

For more details, In the area where the heat-retentive particles are introduced, the maximum temperature is present, steam is introduced by line 4 and fractional distillation is carried out through line 31. Ethane from unit 12 or from other purification units enters the line. - Also because the energy requirements of this reaction are large (catalyst (3 to 6 times that of the Rabking reaction), as the temperature inside the reaction zone is significantly reduced. If downstream, propane (8) or butane (11) or light gas In some cases, heavy saturated hydrocarbons such as phosphorus (11) or naphtha are 38. Add steam from 39 and 40 and inject.

Control systems 41 to 44 are also injected into the reaction zone in a manner known per se. the desired temperature profile by temperature sondes placed in these areas. can hold files.

Compared to the regular steam crab king, the total energy required for the reaction is only once, The heat retaining particles are added at the time of mixing with the charge, i.e. at the beginning of the reaction. Ru.

Therefore, the temperature reaches a maximum at this point, then decreases due to the endothermic reaction of the reaction, and In contrast to conventional methods, a natural slow cooling effect occurs, ie a reduction in the intensity of the reaction.

The temperature profile due to the extremely short reaction times in this device is The reaction selectivity is much higher than that of the results in the removal of dust or tar.

The fluid phase steam cracking apparatus illustrated in FIGS. 2 and 3 is a modification of the apparatus of FIG. In these cases, the reaction zone operates in descending mode. Therefore, this reactor means " It's called a dropper. Components in these figures that are similar to those in FIG. In FIG. 3, the same numbers are shown with a ``''.

In Figure 2, other materials with high resistance to the high temperatures required for steam cracking are shown. Use a mold regenerator. The discharge of this regenerator is transferred to the cyclone outside the regenerator 22°. After passing through 27°, it exits at 28°. Regenerated heat retention above the dropper To locate the particle extraction well 54°, the regeneration chamber 22′ is located at the top of the device. The particles to be deposited and regenerated exit the stripping area through line 23' and pass above. It must be transported through the ascending tower 55'. This conveyance is carried out by line 25'. This is carried out by the flow action of the gas diffused at 26'. During this transport Primary combustion of coke deposited on catalyst particles leads to fluidization containing air or oxygen Performed by gas.

The catalyst particles and fluidizing gas are then separated by a pallitic device 56' and The media particles are regenerated in a known manner in chamber 22', in which The particles are transported by a countercurrent flow of oxygen supplied to the diffuser 46° by line 45'. is burned.

The regenerated catalyst particles have an amount determined by the flow rate of the diffuser 57°. and introduced into the upstream of reactor 1' without hot soaking. Uniformity of particle distribution is here This is ensured by devices of a type known per se, not shown.

At the exit of the dropper 1', the particles are directly transferred to the dense stripping fluidized bed 15'. to which the hydrocarbon vapor and line 20' are supplied. The stripping steam coming out of the diffuser 21' and the stripped charcoal hydrogen hydride is discharged virtually instantaneously through line 17'' and these components are removed from the line 17''. It is instantaneously quenched by dissolving it in the heavy charge entering through tube 18'.

In the variant illustrated in FIG. The regenerated hot air coming from line 2″ allows for dropper mode functionality. Particles first rise to the rising base 58" by the jetting action of fluid such as water vapor coming from line 4". Transported inside. After the particles pass through two right-angled elbows 59'' and 60'', they are uniformly drop into dropper 1”, and within this dropper 7” and 8” sequentially. Next, ethane and gasoline are injected. Next, the rapid cooling of the effluent comes from the heavy The distillation residue of the distillation zone 12" is carried out by the charge and its bubbles are removed from the distillation zone 13". It is injected at a temperature close to the standing point.

Particles exiting the dropper are stripped in a 15" stripping zone. , line 23''. Below this stripping area water vapor or A jet of fluid such as air moves the particles along line 55'' into the regeneration chamber 22°. transported towards. In this regeneration chamber 22'', a pallitic separation device 5 6'' discharges the particles into the fluidized bed combustion zone.

Example This example illustrates the advantages of a device according to the invention of the type illustrated in FIG. these tests uses ethane, gasoline fraction (straight-run fraction) and two charges A and B. It was carried out using These charges were each made by atmospheric steaming of 5HENGLI type crude oil. distillation residue and vacuum distillation residue.

These charges exhibit the following properties:

Gasoline Charge A Charge B -Density (15℃) 0.675 0.955 0.985 1% by volume, distillation temperature 1% by weight, distillation temperature 450℃ knee 20- 550℃ knee 4510 650℃ knee 7055 -H2 (wt%): 15.4 12.1 11.7 -S (wt%): -1 ,01,3 -Total nitrogen (wt%): -0,60,8 -Carbon (wt%): -8,114,2 -Ni+V (ppm): 40 70 Mainly kaolin as heat retention particles It consists of microspheres with a specific surface area of about 10 m2/g and an average diameter of about 70 microns. using contact particles. The inductor into the quenching zone and into the reactor is described in European Patent Application No. 312.428.

The conditions for the two tests conducted sequentially on charge A and charge B are as follows (all Extrapolation to 100t/h charge): Charge A Charge B upstream area of the reactor - of regenerated catalyst Temperature ('C): 880 1180 - of regenerated catalyst Flow rate (t/h) ・　2000　2160-320℃ Steam flow rate (t/h): 15 15-Ethane flow rate D/h): 10 10 -Mixture temperature ('C): 862 868 Reactor midstream zone -320℃ steam flow rate (t/h): -3-150℃ gasoline flow rate knee 30 -Mixture temperature; 825 downstream area of the reactor -320℃ steam flow rate (t/h): 9 6-380℃ Charge A or B flow rate Ct/h): 90 60 - Temperature of mixture ("C): 785 780 - Temperature at the end of reaction ("C): 740 750 quenching area 2 - after ballistic separation Effluent temperature ("C): 730 740 - Charge temperature C"C'l: 80 90 - Mixture temperature ("C): 450 470 - Particle concentration in the effluent (Weight%): 3. 2 2. 2 - temperature of the fractional distillation residue; (’C): 420 440 After recovery of the steam cracking reaction effluents, the properties of these effluents are analyzed. under The analytical results (wt%) collected here are per se the present invention versus conventional methods. demonstrate the advantages of this method.

H2S+NH3 Charge A Charge B H2S+NH30,900,80 H20,900,70 CI 7.90 9.70 C25,605,90 C2 (olefin) 20.50 25.30C30,50,60 C3 (Olefin'I 11.00 11.00C4 (Olefin') 3.2 0 3.10C4 (diolefin) 2.80 3.10C5-220℃ 13 ．． 90　14.80220-360℃　14.40　7.80〉360℃　4. 9 3.70 Coke 13.50 13.50 Therefore, as seen in this test example, the present invention is superior to the prior art steam cracking process. It shows a number of advantages compared to methods. In practice, the method of the present invention is superior to that of the prior art. with efficient equipment and olefin yields at least comparable to conventional steam crackers. The distillation residue that was excluded from King is used in the charge, 1) Operational flexibility (flow rate, charge quality, etc.) that cannot be compared with conventional steam cracking plants (e.g. can be produced without added energy (because coke production satisfies the heat balance of the equipment). move.

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Claims (1)

[Claims] 1. On the one hand, at least a On the one hand, light hydrocarbon fractions and, on the other hand, essentially boiling points above about 400°C. dilution of essentially heat-retaining particles with said heavier hydrocarbon fractions consisting of compounds; 1. A conversion process by high temperature steam cracking in the presence of a liquid phase, said method comprising: The process consists of a gradual and gentle step-wise process in an upflow or downflow tubular continuous reactor. a step of contacting said fraction and then said charge with catalytic or non-catalytic particles; a separation step separating at least 90% of said particles and said hydrocarbon effluent; a tripping step, wherein said separated particles are then preferably After regeneration by the reaction of the coke deposited on the particles, the continuous reaction at a higher temperature is performed. and the separated hydrocarbon effluent is subjected to distillation in a fractionation stage. In the steam cracking method in which the particles are recovered, - a small amount of said heavy hydrocarbon charge between the hydrocarbon effluent separation stage and said distillation stage; a step in which at least a portion of the jet is injected; At least a portion of the residue of the distillative fractionation step is transferred into a downstream section of the reactor. hydrocarbon conversion by steam cracking, characterized in that Law. 2. The heavy hydrocarbon charge has a diameter of less than 200 microns, preferably 100 microns. The method according to claim 1, characterized in that the liquid is sprayed by spraying droplets of 100 ml or less. Law. 3. The steam cracking reaction effluent is brought to a temperature below the dew point by injection of heavy charges. The method according to claim 1 or 2, characterized in that the method is performed in the following manner. 4. The hydrocarbons entering the distillation zone are between 0.01 and 10% by weight, preferably 0.0%. Any one of claims 1 to 3, characterized in that it contains 5 to 5% by weight of heat retention particles. The method described in 5. Prior to the steam cracking reaction effluent distillation step, these effluents are A claim characterized in that it is cooled to a temperature preferably within the range of 320 to 450°C. 5. The method according to any one of 1 to 4. 6. The effluent from the steam cracking zone is liquid and has a temperature in the range of 300 to 450°C. A claim characterized in that the cooling is performed in less than 0.3 seconds, preferably less than 0.1 seconds, at a time. The method according to any one of Items 1 to 5. 7. High-prize hydrocarbon charges include residues from atmospheric or vacuum distillation, catalyst slurry, and Selected from the group consisting of bituminous pitch, or synthetic or used oil. A method according to any one of claims 1 to 6, characterized in that: 8. The distillation residue fraction recycled into the reactor is 10% below the bubble point of this fraction. Claims 1 to 3 are characterized in that the temperature is as high as 0°C or lower, preferably 50°C or lower. 7. The method according to any one of 7. 9. Said liquid heavy charge is at least partially composed of distillation residues of said distillation stage. Any one of claims 1 to 8, characterized in that it is constituted by at least a part of Method described. 10. The distillation residue of the distillation stage is cooled by heat exchange at the outlet of the distillation column. 10. The method according to claim 9, wherein said method is rejected. 11. The light hydrocarbon fraction is a light paraffinic fraction such as ethane, propane, and Specially selected from a group including hydrocarbons, gasoline, naphtha and gas oil. 11. The method according to any one of claims 1 to 10, wherein: 12. including the step of injecting a plurality of light hydrocarbon fractions into the upstream portion of the reactor; The injection of these fractions is carried out in stages by a decreasing sequence of the severity of the injection conditions. 12. The method according to claim 11, characterized in that: 13. The reactor is charged sequentially from upstream to downstream with ethane and then optionally When the temperature of a mixture of light gases containing propane and butane with heat retention particles is 80°C, Inject an amount that will bring the temperature to 0°C or higher, preferably 825°C or higher, and then inject light gasoline. and/or naphtha or gas oil where the immediately downstream mixture temperature is above 750°C. Above, preferably 800℃ or higher is injected, and finally the reaction temperature is 650 to 70℃. including the step of injecting a portion of the distillation residue to reduce the temperature to within a range of 50°C. 13. The method according to claim 12, characterized in that: 14. Ethane and/or propane generated by steam cracking and / or characterized in that at least a portion of the butane product is recycled to the reactor. 14. The method according to any one of claims 1 to 13. 15. The operating pressure of the reaction zone is within the range of 0.3 to 5 kg/cm2. 13. The method according to any one of 13 to 13. 16. On the one hand, there are a number of on the one hand, a light hydrocarbon fraction, and on the other hand, a boiling point essentially above about 400°C. a fluidized phase of heat-retentive particles with said heavier hydrocarbon charge consisting of a compound of A steam cracking blunt by high temperature direct contact conversion in the presence of The blunt comprises contacting the fraction and the charge with catalytic or non-catalytic particles. an upflow or downflow tubular continuous reactor (1) containing at least 90% of said particles; particularly ballistic means (16) for separating and said hydrocarbon effluent; stripping means (20, 21) for said separated particles; Means of regeneration in air or steam combustion conditions of coke deposited on particles (22), means (2) for supplying regenerated particles to said continuous reactor, and also a carbon means (12) for fractionating the hydrohydric effluent by distillation; In the blunt, the blunt is On the other hand, there is a flow between the separation means (16) and the fractionation means (12). means (18, 19) for injecting a portion of said heavy hydrocarbon charge into the effluent; at least a portion of the distillation residue in liquid form but at a temperature close to its bubble point; into the downstream part of the reactor (1) and means (14) for injecting 3) A hydrocarbon steam cracking blunt characterized by comprising: 17. There is also a reactor between the ballistic means (16) and the fractionating means (12). means (18, 19) for injecting said heavy hydrocarbon charge into the downstream portion of (1); 14, 13) is for removing the residue from the distillation fractionation means (12) of the reaction zone effluent. 17. A blunt according to claim 16, characterized in that it is supplied with a. 18. The reactor is charged sequentially from upstream to downstream with ethane and then optionally If the temperature of the mixture of light gas containing propane and butane and heat retention particles is 8. Injecting an amount of the light gas such that the temperature is 00°C or higher, preferably 825°C or higher, and The temperature of the mixture immediately downstream of the injection point is at least 750°C, preferably at least 800°C. amounts of light gasoline and/or hydrocarbon fractions such as naphtha or gas oil; and finally a further heavy hydrocarbon charge in the downstream part of the reactor. means for ejecting in the form of fine droplets with an average diameter of 100 microns or less (7, 9, 1 1, 13) The bra according to claim 16 or 17, characterized by comprising: nt. 19. means (53) for injecting fresh heat retaining particles into the steam cracking effluent; ) The blunt according to any one of claims 16 to 18.