US3760168A - Reaction zone control - Google Patents

Reaction zone control Download PDF

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Publication number
US3760168A
US3760168A US00146400A US3760168DA US3760168A US 3760168 A US3760168 A US 3760168A US 00146400 A US00146400 A US 00146400A US 3760168D A US3760168D A US 3760168DA US 3760168 A US3760168 A US 3760168A
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reaction
output signal
effluent
reaction zone
performance
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D Boyd
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Honeywell UOP LLC
Universal Oil Products Co
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Universal Oil Products Co
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    • C—CHEMISTRY; METALLURGY
    • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
    • C10G—CRACKING HYDROCARBON OILS; PRODUCTION OF LIQUID HYDROCARBON MIXTURES, e.g. BY DESTRUCTIVE HYDROGENATION, OLIGOMERISATION, POLYMERISATION; RECOVERY OF HYDROCARBON OILS FROM OIL-SHALE, OIL-SAND, OR GASES; REFINING MIXTURES MAINLY CONSISTING OF HYDROCARBONS; REFORMING OF NAPHTHA; MINERAL WAXES
    • C10G35/00—Reforming naphtha
    • C10G35/24—Controlling or regulating of reforming operations
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C5/00—Preparation of hydrocarbons from hydrocarbons containing the same number of carbon atoms
    • C07C5/32—Preparation of hydrocarbons from hydrocarbons containing the same number of carbon atoms by dehydrogenation with formation of free hydrogen
    • C07C5/327—Formation of non-aromatic carbon-to-carbon double bonds only
    • C07C5/333—Catalytic processes
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10S585/00—Chemistry of hydrocarbon compounds
    • Y10S585/919—Apparatus considerations
    • Y10S585/921—Apparatus considerations using recited apparatus structure
    • Y10S585/922—Reactor fluid manipulating device
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10S585/00—Chemistry of hydrocarbon compounds
    • Y10S585/919—Apparatus considerations
    • Y10S585/921—Apparatus considerations using recited apparatus structure
    • Y10S585/924—Reactor shape or disposition
    • Y10S585/926—Plurality or verticality

Definitions

  • the optimizer analyzes the performance index output signal and then determines a first output signal necessary for each reaction zone to approach an optimum performance in the reaction zones.
  • a controller utilizes the signal indicative of the conversion level of the reaction zones and determines a second output signal representing a second component of the regulatable set points corresponding to the desired total conversion level of the reaction zones.
  • the first and second output signals are combined and are utilized as the regulatable set points for controlling the regulation of the severity of reaction in each reaction zone.
  • Optimizer means is litilized to optimize the performance index and the signal derived from the optimizer means is used in conjunction with the signal from the controller means to adjust the reaction zone severity.
  • Typical of applicable conversion processes is catalytic hydrore'forming, wherein a naphtha fraction is passed into a reaction zone containing noble metal catalysts, in the presence of molar excess of hydrogen.
  • Another hydrocarbon conversion process which may utilize the concept of this invention is the dehydrogenation of ethylbenzene to styrene.
  • control system include any reaction processes such as thermocracking, catalyticcracking, thermo hydrocracking, catalytic hydrocracking, isomerization, alkylation, polymerization, and the like.
  • the catalytic reforming unit producing high octane motor fuel typically is maintained at operating conditions sufficient to enhance the dehydrogenation of naphthenes and the dehydrocyclization of paraffins in order to maximize the production of both aromatics and hydrogen, maximum hydrogen being desired since it is normally consumed elsewhere in the typical petroleum refinery.
  • the production of aromatic hydrocarbons is enhanced by catalytic reforming at a temperature in the range of from about 850 F to about 1,050 P and at a pressure in the range of from about psig to about 400 psig when the end boiling point of the charge stock is about 350 F, but when the end point of the charge stock is about 400 F or more, the pre ferred pressure is about 500 psig in order to maintain catalyst stability.
  • the operator of the catalytic reforming unit judiciously selects the operating conditions which he believes will most economically produce the desired high octane gasoline.
  • the naphtha charge stock is passed into the reaction zone under conditions of temperature,
  • the resulting hot vaporous reactor effluent containing hydrogen, normally gaseous hydrocarbons and gasoline boiling range hydrocarbons is withdrawn from the reaction zone, cooled, condensed, and passed to a separation zone which is normally a single stage gravitytype phase separator maintained at reforming pressure of, say, 50-500 psig.
  • the liquid hydrocarbon or unstabilized reforrnate phase is in equilibrium therein with the gas phase containing a major proportion of the hydrogen.
  • the hydrogen-rich vapor phase is withdrawn and a portion thereof is recycled to the inlet of the catalytic reforming zone for circulation across the catalyst together with the naphtha charge.
  • the liquid hydrocarbon phase from the separator is then ultimately fed to a distillation zone which normally comprises a stabilizer column.
  • a typical sample of catalytic reformate from a separator operating at 250 psig consists of:
  • Component s C,-400"F endpoint The overhead from the stabilizer column is predominately C and lighter hydrocarbons, and the column bottoms is stabilized gasoline typically comprising predominately C to about 400 F endpoint material.
  • the rate of the reaction also decreases so that the overall conversion percentage of ethylbenzene in the process declines to a point where it would be economically unattractive.
  • the temperature of the superheated steam may be increased so that the temperature between the inlet temperature of the reactants and the outlet temperature of the reaction products average equals the required reaction temperature.
  • the ethylbenzene undergoes, to some extent decomposition or cracking through a pyrolytic reaction.
  • Another object of this invention is to provide the method and means of controlling a continuous hydrocarbon conversion process.
  • the present invention provides for in combination with at least two reaction zones having inlet means for introducing an inlet effluent therein and outlet means for discharging the resultant outlet effluent therefrom, a control system which maintains a desired total conversion level of operation and which optimizes the performance thereof comprising: (a) regulating means connected to eachreaction zone for regulating the severity of reaction therein; (b) a control means connected to each regulating means for controlling, the regulation thereof, each control means including a regulatable set point; (c) analyzing means communicating with the effluent of the downstream reaction zone for producing a signal responsive to the character of the outlet effluent; (d) performance indicating means connected to said analyzing means for determining a performance index output signal; (e) optimizer means connected to the performance indicating means for optimizing the performance of said reaction zones, said optimizer means including means for determining a first output signal for each control means representing a first component of the aforesaid regulatable set points and including computer means for analyzing
  • the performance index output signal is comprised of a function of 1) the undesirable products in the outlet effluent with respect to (2) the desirable products in the outlet effluent.
  • the performance index signal may comprise the ratio of undesirable products in the outlet effluent to the desirable products in the outlet effluent.
  • the optimizer means will then determine a first output signal for each control means to approach a minimum value of this particular ratio.
  • the regulating means may include means to regulate the heat input to each reaction zone; however, this should not be considered limiting upon the present invention.
  • the pressure may be controlled to vary the severity of each reaction zone in the vessel.
  • the amount of an input fluid may be regulated to control the severity of reaction.
  • the conversion level may be determined by a function of the desired products in the outlet effluent with respect to the unreacted reactants remaining in the ef fluent. On the other hand, if dealing with a particular vessel such as a reforming reaction vessel, the conversion level may be determined by the octane rating of the liquid outlet effluent.
  • Another aspect of the present invention provides for a method of controlling the operation of at least two connecting reaction zones comprising the steps of: (a) regulating the severity of reaction within each reaction zone; (b) controllingsuch regulation in response to a regulatable set point signal for each reaction zone; (0) analyzing the outlet effluent of the downstream reac tion zone to produce a signal responsive to the character of said outlet effluent; (d) determining a performance index output signal from the signal derived from step (i c); (e) optimizing the performance of said reacbining each first output signal with the second output.
  • the performance index output signal may be comprised of a function of undesirable products in the outlet effluent in respect to the desirable products in the outlet effluent.
  • the conversion level may be determined by a function of thedesired products in the out let effluent with respect to the unreacted reactants remaining in the outlet effluent or on the other hand it may be determined by the octane rating of the outlet effluent.
  • the severity of reaction may be regulatedby regulating the heat input to each reaction zone, the pressure of each reaction zone, the amount of input effluent to the reaction zone, and the like.
  • a specific embodiment of this invention provides for from, a method of controlling such process which comprises the steps of: (a) regulating the severity of reaction within each catalytic reaction zone; (b) controlling such' regulation in response to a regulatable set point signal for each reaction zone; (0) analyzing the outlet effluent of the downstream reaction zone to produce signals responsive to: (1) the quantity of benzene in said outlet effluent, (2) the quantity of toluene in said outlet effluent, (3) the quantity of styrene in said outlet effluent, and (4) the quantity of ethylbenzene in said outlet effluent; (d) determining a performance index output signal from signals (1), (2), and (3) of step (c), the value of said performance index output signal being given by a function of: (l) the sum of the quantities of benzene and toluene with respect to (2 the quantity of styrene; (e) optimizing the performance of the catalytic reaction zones by analyzing the performance index output signal of step (
  • the performance output signal is derived from a signal determined by the ratio of the sum of quantities of benzene and toluene to the quantity of styrene in the outlet effluent.
  • the first output signals determined by analyzing and optimizing the performance output signal is determined by minimizing this ratio.
  • the conversion level is preferably given by the ratio of the quantity of stryene to the quantity of ethylbenzene in the outlet effluent.
  • a proportional controller or the like may be utilized to determine a second output signal representing a second component of the regulatable set points by a comparison of the conversion level determined in step (1) and a desired conversion level of 80 percent.
  • the preferred mode of regulating the rate of reaction or the severity of reaction utilizes means which regulates the input of steam to the reactor. This may comprise control valves, pumping and the like connectable to the inlet steam means.
  • Another specific embodiment of the present invention is related to the process of reforming hydrocarbon charge stocks wherein the hydrocarbon charge stock is passedthroug'h at least two catalytic reaction zones and a a total product effluent is discharged therefrom.
  • the invention provides for a method of controlling such a .process which includes the steps of: (a) regulating th ing the outlet effluent of the downstream reaction zone to produce signals responsive to: (l) the liquid yieldin said product effluent and (2) the octane value of the liquid yield; (d) optimizing the performance of the reaction zones by analyzing signal (1) of step (c) and determining a first output signal necessary for each reaction zone to approach an optimum performance of said reactor, each first output signal representing a first component of the aforesaid regulatable set point signals; (e) determining a second output signal representing a second component of the aforesaid regulatable set point signals whose value is determined by the comparison of the desired octane value of the liquid yield and the
  • FIG. 1 illustrates schematically reaction apparatus having two reaction zones wherein the heat input to each zone controls the regulation of the rate of reaction or severity of reaction.
  • FIG. 2 illustrates schematically hypothetical performance curves of a reactor installation.
  • FIG. 3 illustrates schematically a typical reactor system which may be utilized for the dehydrogenation of ethylbenzene to styrene and which uses the control system of the present invention.
  • FIG. 4 illustrates a catalytic reforming unit wherein the heat input to two reaction zones is used to regulate the reaction severity.
  • FIG. 1 there is shown a simplified schematical flow diagram for a typical reaction installation.
  • Reactors 1 and 1' may be one of the many reactors utilized in reaction processes as for example catalytic reforming, ethylbenzene dehydrogenation, thermocracking, catalytic cracking, thermo hydrocracking, catalytic hydrocracking, isomerization, alkylation, polymerization and the like.
  • Reactor 1 has inlet means 2 for introducing the inlet effluent therein.
  • heater 4 is provided in conjunction with inlet 2 and may be any type of heat exchanger employing any type of heating medium such as steam, hot oil, hot vapor flue gas, etc.
  • the heater 4 is a direct fired furnace having a burner 5 which is supplied through line 6 with fuel. The reaction mixture or effluent is heated within coils 7 in heater 4.
  • the heated reaction mixture leaves heater 4 via line 2 and is passed into reaction zone 1 at a pressure which of course will depend on the particular reaction desired.
  • the effluent from reaction zone 1 is discharged through outlet 3 and is passed through downstream reheater 4 of similar configuration as heater 4.
  • the reacted mixture leaves this heater and is passed into reaction zone 1' via inlet 34.
  • the total reaction zone effluent is discharged through outlet line 3 for storing or further processing.
  • the regulation of the rate of reaction or severity in the reactors in this particular embodiment is by the heat input into each reaction zone.
  • the heat input to the reaction zone is provided by introducing a fuel via lines 6 and 6' into the combustion burners 5 and 5 within heaters 4 and 4'.
  • Fuel which may be liquid or gas is burned within the combustion zones and the hot combustion gases pass through the furnaces and out the stacks. As the fuel is burned and the combustion gas passes through furnaces, the necessary heat is put into the reaction mixture contained within coils 7 and 7 by means of radiation and convection.
  • the heat input into the reaction mixture is controlled and adjusted by varying the flow of fuel to combustion burners 5 and 5.
  • This control of flow of fuel is achieved by means of a flow control loop contained in lines 6 and 6.
  • the flow control loop comprises control valves 8 and 8' and flow sensing means 9 and 9', which for illustrative purposes are shown as orifices.
  • Flow signal lines 10 and 10' transmit the flow signal from each orifice 9 and 9' to flow controllers 12 and 12'.
  • Flow controllers 12 and 12 then transmit an output signal to the control valves 8 and 8' via lines 13 and 13.
  • the set point of fiow controllers l2 and 12 is automatically adjustable or regulatable.
  • Temperature controllers l4 and 14' also with automatically adjustable set points, sense inlet temperature of reactors, as detected by thermocouples or other sensing means 15 and 15' located in inlet lines 2 and 34 of the reactor. The resulting temperature output signals are transmitted from temperature controllers 14 and 14 to flow controllers 12 and 12 via lines 17 and 17' to adjust or reset the set points of flow controllers 12 and 12 respectively.
  • An analyzer 18 is installed to be in communication with the outlet effluent of the downstream reactor 1 via line 19.
  • Line 19 represents a suitable sampling system to provide a continuous sample of the outlet effluent of the reactor installation.
  • the sample is withdrawn from line 3 and is passed into analyzer 18 for analysis.
  • the analyzer of FIG. 1 should be constructed to include analyzing means capable of producing a signal or signals responsive to the character of the outlet effluent.
  • the analyzer may include analyzers such as chromatographs, continuous octane monitors, as well as continuous flow monitors which determine the total flow through outlet 3.
  • At least two outlet signals are determined by analyzer 18 and will include a signal representing a particular conversion level and a signal to be utilized for determining a performance index of the reactor.
  • the conversion level output signal is transmitted via line 20 to a recorder controller 21.
  • Controller 21 has a set point which is adjustable and which is adjusted to the preferred conversion level. As for example, if the conversion level is to be determined by the octane value of the liquid yield in line 3, controller 21 will have a set point corresponding to the desired octane value of the outlet effluent in line 3.
  • the output signal from the controller 21 is transmitted via line 23 through summing amplifiers 24 and 24'.
  • the output signal from the summing amplifiers 24 and 24' which will be the total signal from controller 21 and from an optimizer 30 is transmitted via lines 25 and 25 to the set points ofthe temperature controllers 14 and 14.
  • analyzer 18 will also be capable of determining a signal or signals to be utilized for determining a performance index of the reactor installation.
  • the optimizer may be a chromatograph which would generate a signal determinate of the amounts of undesirable products in the outlet efiluent and a signal determinate of the desirable products in the outlet effluent. These two signals may be transmitted via lines 26 and 27 to a performance index determination device 28.
  • the signal determined by the analyzer 18 is a performance signal capable of being optimized in itself, it may be transmitted directly to the optimizer 30.
  • Performance index determination device 28 may be an operational amplifier capable of determining a function of the signals from the analyzer which is indicative of the performance of the reactor and which is capable of being optimized.
  • performance index determination device 28 may be an operational amplifier capable of determining the ratio of the signal representing the quantity of undesirable products in the reaction effluent to the signal representing the quantity of the desirable products in the reaction effluent.
  • This signal is transmitted via transmitting means 29 to the optimizer 30.
  • the optimizer has means for determining an output signal for the control means of each reaction zone which are then transmitted via lines 31 and 33 to the summing amplifiers 24 and 24' respectively.
  • the output signals in lines 31 and 33 representing first components of the set points of the temperature controllers and the output signal of line 23 representing a second component of the set points for the temperature controller are combined in summing amplifiers 24 and 24' and transmitted to the set points of the temperature controllers via lines and 25.
  • the optimizer has computer means to determine th performance index output signal of line 29 and to determine the output signal necessary for each reaction zone to approach an optimum performance in the reactor vessels.
  • Optimizer is a device well known in the art which maximizes or minimizes some measure of process performance.
  • the reactors performance index may be determined by the ratio of undesirable products to desirable products in the product effluent and this ratio will vary with the heat input to each reaction zone. It is noted that the ratio for each reaction zone goes through a minimum at point where the slope of the curve is zero as shown in FIG. 2 of the drawing.
  • zone 1 is operating at the position as shown as point a on the curve, and zone 1 is operating at point d of its curve the optimizer computer will determine the output sig nals necessary to alter the set points of the respective temperature controllers so that the ratio of undesirable products to desirable products will approach b, and 2 respectively, the minimums on the curves.
  • point c is the point on th curve which zone 1 is operating
  • f is the point in the curve where zone 1 is operating
  • the optimizers computer will determine output signals necessary so that the severity of each reactor zone will approach 12 and e respectively on the curves. It makes no difference if an optimum actually exists or at which point it exists.
  • the optimizer adjusts its outputs to improve the performance. Reference may be made to pages 22-52 through 22-54 of Perrys Chemical Engineering Handbook, fourth edition, published by McGraw-Hill Book Company for a brief description of optimizer theory.
  • optimizers there are various types of optimizers on the market, including the Motorola Veritrak performance optimizer controller manufactured by Motorola, Instrumentation and Control Inc. of Phoenix, Arizona, a subsidiary of Motorola, line.
  • This particular optimizer is an analogue computer that operates on the principle of introducing small output changes and noting the effect on the index or indices it scans. By noting the effect, it can reach a decision to change the output signals necessary to approach an optimum performance of the reiii actor.
  • the performance index it scans need not be the index of each reaction zone for the optimizer. It may be set up to only scan the performance index of the total reaction zone defined by zones l and l although theoretically the optimizer may scan more than one performance index.
  • the small perturbations or changes in each reaction zone are made out of sequence with each other.
  • the optimizer can more readily differentiate which perturbation in which reaction zone caused the performance index to change and thus make its decision as to each reaction zone.
  • the analyzer output signal 20 will transmit a new signal.
  • Controller 21 will transmit an output signal in transmitting line 23 to the summing amplifiers 24 and 24'. This signal would be a second component of the temperature controller set points and would correspond to a value which would make the total reaction severity lie within the desired conversion level.
  • the decisions of controller 21 are made out of sequence with any changes made by the optimizer so the causes of any changes in the performance index: are recognizable.
  • analyzer 18 will be of the type that can analyze such quantities and transmit signals indicative thereof. These signals will be transmitted via line 26 and 27 to a performance index determination device which would be an operational amplifier capable of determining and transmitting a signal representing the ratio of undesirable products to desirable products in the outlet effluent. This output signal would be transmitted to the optimizer 30 via line 29 and the optimizer would determine the output signals that would cause the reaction severity of each reaction zone to ap proach a ratio of undesirable products to desirable products corresponding to a minimum. This signal would be transmitted via line 31 and 33 to summing amplifiers 24 and 24 where the signal from line 23 would be added to any existing from signal line 23. The two combined signals would make up the set points of the temperature controllers 14 and 14' which would in turn adjust the set points of the controllers I2 and 12' thus affecting the heat input to each reaction zone.
  • a reactor 51 which in this particular embodiment is a three stage reactor having catalyst zones A, B, and C.
  • This particular reactor is. useful for the dehydrogenation of ethylbenzene to styrene.
  • the catalyst employed for this dehydrogenation reaction is preferably an alkali-promoted iron catalyst.
  • a catalyst may consist of percent by weight ferrous oxide, 2 percent by weight of chro-mia, 12 percent by weight of potassium hydroxide, and 1 percent by weight of sodium hydroxide.
  • Other catalyst compositions include percent by weight iron oxide, 4 percent by weight chromia, and 6 percent by weight potassium carbonate. While these known commercial dehydrogenation catalysts are preferred, other known catalysts may be used, including those comprising ferrous oxide-potassium oxide, other metal oxides and/or sulfides, including those of calcium, lighium, strontium,
  • the amount of catalyst contained in each catalyst bed may be varied considerably.
  • the amount of catalyst is expressed in terms of bed depth which may range from 6 inches to 50 to 60 feet, depending upon such conditions as alkylated aromatic hydrocarbon feed rate and the amount of heat which therefore must be added to effectuate the reaction at an economical rate.
  • the bed depth may range from 2 feet to 6 feet.
  • the reactor pressure may also be varied over a considerable range.
  • a slightly superatmospheric pressure e.g., 4-20 psi g
  • Sufficient pressure must be maintained at the reactor inlet to overcome the pressure drop through the multi-beds of catalyst contained in the reactor vessels or in separate vessels if each such bed is contained in a separate reactor.
  • the preferred arrangement of the reaction zones for styrene production is shown as multiple beds contained in a single reactor, single beds in multiple reactors, may be used in the practice of this invention.
  • the temperature of the effluent leaving the first catalyst bed would probably be in the order of 100 F or more, less than the inlet temperature selected for the combined charge material to the first catalyst bed.
  • the pressure of the effluent from the first catalyst bed preferably would be less than 10 psig lower than the selected pressure for the combined charge to the first catalyst bed.
  • the pressure drop through the first catalyst bed would be within the range from 2 to 6 psig and if a similar pressure drop were observed across, for example, three catalyst beds, the total pressure required at the inlet of the first catalyst bed would be significant, e.g., in the range from 6 to 18 psig.
  • Superheated steam at a temperature of about l,400 F is introduced into the inlet 52 to the reactor via steam line 85 at a ratio of about 0.65 pounds of steam to 1.0 pounds of ethylbenzene and is admixed with the ethybenzene to a nominal temperature of about 1,200 F (as defined in the prior art the dehydrogenation of ethylbenzene is generally affected at a reactor temperature within the range of about 932 to 1,292 F).
  • a second steam line 85' is used to introduce superheated steam at a nominal temperature of about l,500 F in between catalyst zones A and B at a ratio of about 1.0 to 1.2 pounds of steam to effluent to raise the temperature of the total effluent to reaction temperatures.
  • a third steam line 85" is used to introduce super-heated steam at a nominal temperature about 1,500 F into admixture with the total effluent between zones B and C at a ratio of about 0.80 to 1.35 poundsof steam to effluent to raise the temperature of the effluent to reaction temperatures.
  • the total outlet effluent having a temperature within the range of about l,000 to 1,400 F is discharged through outlet conduit means 53.
  • a flow control loop is provided for each steam inlet to vary the flow of steam into the reactor at each point of introduction to thus control reaction zone severity.
  • the flow control loop comprises flow control valves 58, 58' and 58" receiving output signals via lines 53, 53' and 53" from flow controller 62, 62' and 62" respectively.
  • Flow controllers 62, 62' and 62" receive the flow rate signals from sensing means 59, 59' and 59" via flow signal lines 60, 60 and 60" respectively.
  • Flow controllers 62, 62 and 62" have adjustable set points which are reset by the output signals of temperature controllers 64, 64 and 64" respectively, said output signals being transmitted via line 67, 67 and 67
  • Each temperature controller receives a temperature signal from the inlet of each reactor zone A, B, and C respectively by means of temperature sensing devices such as thermocouples 65, 65 and 65
  • Temperature controllers 64, 64' and 64" also have adjustable set points.
  • the product effluent from outlet 53 is sampled by an analyzer 68 by means of a sampling loop 69.
  • the analyzer 68 may be a chromatograph capable of determining output signals of the products and/or reactants in the outlet effluent.
  • the output signals which are utilized in the present invention are: quantity of benzene; quantity of toluene; quantity of styrene; and quantity of ethylbenzene. These signals are transmitted via lines 86, 87, 88 and 89 respectively to four input memory amplifiers 35, 36, 37 and 38 respectively.
  • the signal that the memory amplifiers will accept will indicate only the peak height of these products benzene, toluene, styrene and ethylbenzene although filtered or average values are contemplated.
  • the output of the styrene memory amplifier 37 and ethylbenzene memory amplifier 38 are transmitted via lines 43 and 44 to a divider 45 and the quotient output signal representing the ratio of styrene to ethylbenzene is transmitted to a recorder controller 71 via line having a set point adjusted to the desired ratio of styrene to ethylbenzene.
  • the output of this controller is fed simultaneously through the feed forward input of three summing amplifiers 74, 74 and 74" via line 73 whose output is finally transmitted to the temperature controller set points via line 75, 75 and 75
  • the output of the benzene memory amplifier 35 and toluene memory amplifier 36 is transmitted via lines 39 and 40 to a summing amplifier 46.
  • the signal of summing amplifier 46 represents the sum of benzene and toluene and its signal is transmitted via line 41 to a divider 47.
  • the output of the styrene memory amplifier 37 is transmitted via line 42 to the divider 47 and the output of the divider which represents the ratio of benzene plus toluene to styrene (B T)/S is transmitted via line 79 to an optimizer 80.
  • the output in line 79 represents the performance signal of the reactor 51.
  • the optimizer by introducing small perturbations into the control process via the temperature controllers 64, 64' and 64" notes the effct on the performance index B T)/S and determines an output signal necessary for each reaction zone to approach an optimum performance index (in this case a minimum).
  • the output signals from the optimizer are transmitted via line 81, 87 and 88 to the summing amplifiers 74, 74 and 74".
  • the signals from the summing amplifiers correspond to the set points of the temperature controllers 64, 64 and 64" and thus regulate the steam input and consequently the heat input into each catalytically active zones A, B, and C.
  • the proportional controller 71 adjusts the set point of the temperature controllers 64 in response to a desired conversion level determined by the ratio of styrene to ethylbenzene in the conduit 53 and the optimizer80 adjusts each set point of the temperature controller 64, 64 and 64" by minimizing the ratio of the undesirable products of benzene to toluene to styrene in the product effluent.
  • the small perturbations made by the optimizer for making a decision as to each reaction zone are preferably made out of sequence with each other.
  • the optimizer can differentiate which perturbations in which reaction zone cause the performance index to change and thus make its decision as to each reaction zone.
  • the signals from the proportional controller are the second component of the set points and of course correspond to a value which maintains the ratio of styrene to ethylbenzene within or about a desired range; e .g., 60 percent.
  • any changes made by the proportional controller are made out of sequence with any changes made by the optimizer so causes of any changes in the ratio (B T)/S are recognizable.
  • FIG. 4 of the drawing there is shown a simplified schematic flow diagram for a typical catalytic reforming unit which utilizes the inventive control system.
  • a low octane number feedstock comprising naphtha or gasoline boiling range hydrocarbon constituents, having an end boiling point of about 350 F enters the reforming process via line 100.
  • a recycleinto a reactor preheater 104 which may be any type of heat exchanger employing any type of heating mediums such as steam, hot oil, hot vapor, flue gas, etc. Normally however, in order to achieve the high temperature required, preheater. 104 will be a direct fired furnace as illustrated.
  • the reaction mixture of the hydrocarbon and hydrogen is heated within a coil 107 of preheater 104.
  • the heated reaction mixture leaves preheater 104 via line 102, typically at a temperature of from about 900 to l,00O F depending upon the composition of hydrocarbon feedstock.
  • the hot mixture charge stock.
  • the reactor effluent passes via line 150 to a reheater 154 which may be similar to preheater 104.
  • the effluent is heated within a coil 157.
  • the reheated mixture leaves reheater 154 via line 152 typically at a temperature of from about 900 to l,000 F.
  • the hot mixture passes into a second reactor zone comprised of a reactor vessel 151 at a pressure of about 300 psig having suitable catalyst therein whereby such mixture undergoes a further conversion to lower boiling hydrocarbon constituents having a higher octane number.
  • the reactor mixture leaves reaction zone 15] via line 103 at a somewhat lower temperature and passes into a heat exchanger wherein the mixture is cooled and normally liquid constituents are condensed.
  • the condensed and cooled mixture leaves the heat exchanger 135 at a temperature of about 60 to 120 F, and passes into a separator 136 via line 137.
  • Separator 136 will be at a pressure which is substantially the same pressure as the reaction zone, but it will be at a slightly lower level due to pressure drop through the reactors catalyst beds, line 150, heater 154, line 152, line 103, heat exchanger 135, and line 137. Thus, whereas the reactor 101 will typically be at an inlet pressure of about 300 psig, separator 136 will typically be at a pressure of about 250 psig or lower.
  • the condensed and cooled effluent entering separator 136 via line 137 is separated therein into a vapor phase and a liquid phase. The vapor phase is withdrawn via line 99 for recycle to the reaction zones.
  • Compressor means not shown, sends the hydrogen-rich vapor phase via line 99 into line 100 for mixture with the charge stock, as was previously set forth hereinabove.
  • the catalytic reforming reaction not only upgrades the hydrocarbon constituents to higher octane number components, but it also produces hydrogen as a byproduct of the process. Consequently, a net hydrogen-rich gas is withdrawn via line 140 by conventional pressure control means, not shown, as a net gas product which is typically sent to further processing units for consumption elsewhere in the refinery.
  • the liquid phase containing dissolved gaseous components is withdrawn from separator 136 via line 141 and is passed through a control valve 142 usually into a fractionation zone (not shown).
  • the liquid phase withdraw rate typically is adjusted via a liquid level controller (not shown) which may be operated by a level sensing means in the separator.
  • the level control ler would adjust valve 142 by transmitting a pneumatic, electrical, or hydraulic output signal.
  • Heat input to reaction zones is provided by introducing a fuel via lines 106 and 156 into burner 105 in the preheater 104 and burner of reheater 154 respectively.
  • the fuel which may be a liquid or gas, is burned within the combustion chambers and the hot combustion gases pass through the furnace and out of the stack. As the fuel is burned and the combustion gas passes through the furnace, it imparts the necessary heat input into the reaction mixture contained within the coils 107 and 157 by means of radiation and convection.
  • the heat input into the reaction mixture is controlled and adjusted by varying the flow of fuel to the burners 105 and 155.
  • This control flow of fuel is achieved by means of a flow control loop similar to that shown in FIG. 1 of the drawing.
  • the flow control loop of each reaction zone comprises control valves 108 and 108' and flow sensing means 109 and 109' which for illustrative purposes are shown as orifices.
  • Flow signal lines 1 10 and 1 10' transmit the flow signals from the orifices 109 and 109 to flow controllers 112 and 112".
  • Flow controllers 112 and 112' then transmit output signals to respective control valves 108 and 108' via lines 1 13 and 113'.
  • the set point of flow controllers 112 and 112 are automatically adjustable.
  • Temperature controllers 114 and 114 also with an automatically adjustable or regulatable set points, sense the reactor inlet temperature as detected by thermocouples or other sensing means 115 and 115' located in the inlet lines 102 and 152 or other suitable inlet portions of the reaction zones. The resulting temperature output signals are transmitted from temperature controllers 114 and 114' to fluid controllers 112 and 112 via lines 117 and 117 60 adjust or reset the set points of each flow controller.
  • An octane monitor 118 which may be the type described in US. Pat. No. 3,463,613 issued Aug. 26, 1969 to ER. Fenske and J.l-l. McLoughlin is installed in line 143 connected with the liquid discharge of separator 136. It is connected through a suitable sampling line 119 to provide a continuous sample of the liquid phase of the reactor effluent. The sample is withdrawn and passed into the octane analyzer or monitor without intervening depressurization.
  • the octane monitor utilized a stabilized cool flame generator with a servo-positioned flame front.
  • the flow of the oxidizer (air) and (fuel) effluent liquid phase sample are fixed, as is the induction zone temperature.
  • Combustion pressure is the parameter which is varied in a manner to immobilize the stabilized cool flame front.
  • the change in pressure required to immobilize the flame front within the octane monitor provides a direct indication of the change of octane number in the sample delivered to the combustion chamber of the octane monitor.
  • Typical operating conditions for the octane monitor are:
  • the sample may be drawn off at a rate of about 100 cc per minute from a point upstream of the control valve 142 and returning it downstream from the control valve 142 the sample itself being drawn off from an intermediate portion of the sample loop and injected at a controlled rate by a metering pump to the combustion tube of the octane monitor.
  • the octane monitor output signal is transmitted via line 120 to a recorder controller 121.
  • the octane monitor Upon a decrease in the measured octane number of the liquid phase sample, the octane monitor will call for an increase in the reaction zone temperature in order to dehydrogenate a greater proportion of the naphthenes in the charge stock, to produce a greater amount of high octane aromatic hydrocarbon in the effluent.
  • the recordercontroller 121 will call for an increase in the flow of fuel which is done indirectly through summing amplifiers 124 and 124'.
  • the output of the recorder controller 121 is connected via line 131 to summing amplifiers 124 and 124' and via lines 125 and 125' to the set point of the temperature controllers 114 and 114'.
  • Summing amplifiers 124 and 124 combine the signal from the recorder controller 121 and the signals from an optimizer 130.
  • Temperature controllers 114 and 114 then will call for an in crease in the flow of fuel to the heaters 104 and 154 in order to increase the heat input into the reactants in coils 107 and 157 and thereby increase the temperature of the reaction mixture entering the reaction zones.
  • the octane monitor will call for a decrease in the reaction zone temperature and the overall corrective action will be the reverse of that previously described.
  • the octane number of the liquid phase of the reactor effluent is continuously monitored and the reaction zone is controlled under conversion conditions sufficient to provide a substantially constant octane number on the liquid phase of the efiluent at a constant predetermined level.
  • the present invention as another factor to adjust the set points of the temperature controllers and that being the signals derived from optimizer 130.
  • Optimizer may be of the type previously described which introduces perturbations into the input of each reaction zone and notes the effect on the'perforrnance index it scans. In this particular embodiment, the performance index the optimizer scans is determined by the liquid yield.
  • a flow sensing means 143 in line 141 downstream of the separator 136 which for illustrative purposes is shown as an orifice.
  • a flow signal line 144 transmits the flow signal from the orifice 143 to memory amplifier 145.
  • Memory amplifier 145 transmits the peak rate of flow to the optimizer 130 via transmitting line 146 although an average or filtered ratio may be used.
  • the optimizer in turn transmits output signals via lines 147 and 197 to summing amplifiers 124 and 124' respectively.
  • Summing amplifiers 124 and 124 add the signals from line 147 and Y197 to the signal from line 131 and transmit these output signals via lines 125 and 125' to corresponding temperature controllers to ad just the set points thereof.
  • the optimizer will sense a signal indicating the liquid yield quantity of flow. It will introduce small perturbations into each reaction zone via its output to the temperature controllers 114 and 114 which will vary the heat input into each reaction zone.
  • the optimizer merely transmits signals that will increase the yield. But, it will not increase the yield to the exclusive detriment of the octane value since the octane is being continually monitored and controlled by the recorder controller 121 preferably out of sequence with the optimizer.
  • the present invention should not be considered directed to merely a system where the heat input is controlled in order to control the severity of reaction but may be directed on the other hand, to systems where one of the components of the feed is the variable to control the severity of the reaction. Also, it is noted that the temperature controllers used only one sensing means to determine the severity of the reaction in all three embodiments It is also contemplated to use a temperature controller whose set point is determined by aAT across the reaction zone.
  • the primary advantage is that the present invention maintains a particular range of operation, e.g. percent conversion, octane level, and yet optimizes a related but not necessarily dependent performance index by regulating the severity of connecting reaction zones.
  • the range of operation controller may be set to update the temperature controller set point periodically, for example, every minutes, and the signal from the optimizer may be used to update the tempera ture controller set point every 60 minutes.
  • the signal from the optimizer may be used to update the tempera ture controller set point every 60 minutes.
  • other time periods may be considered to be in the scope of this invention.
  • thermocracking catalytic cracking
  • thermo hydrocracking catalytic hydrocracking
  • isomerization alkylation, polymerization, and the like.
  • inventive control system has been disclosed with reference to the control of conversion or reaction severity or rate of reaction by the adjustment and control of heat input, e.g. (I) steam, (2) heaters
  • inventive control system may be utilized to control severity or rate of reaction by the adjustment of any other operating variable.
  • the inventive control system may be utilized to control the rate of catalyst circulation.
  • the inventive control system may adjust reaction severity by adjustments to the rate of circulation of isobutane reac- 5 tant.
  • inventive control system may adjust reaction severity by adjusting the rate of flow of olefin reactant to the reaction zone.
  • the adjustments to the conversion or reaction severity made by the inventive control system will result in the production of the ultimate product within the specification, range of operation, and with the performance index optimizer therein.
  • a control system which maintains a desired range of operation and optimizes the performance thereof comprising:
  • regulating means connected to each reaction zone for regulating the severity of reaction therein;
  • each control means including a regulatable set point
  • analyzing means communicating with the effluent of the downstream reaction zone for producing a signal responsive to the character of said effluent
  • performance indicating means connected to said analyzing means for determining a performance index output signal
  • optimizer means connected to the performance indicating means for optimizing the performance of said reaction zones, said optimizer means including means for determining a first output signal for each said control means and including computer means for analyzing the performance index output signal of said performance indicating means to determine said first output signal necessary for each reaction zone to approach an optimum performance of said reaction zones;
  • controller means connected to said analyzing means for determining a second output signal corresponding to the desired conversion level of said reaction zones;
  • summing means connected to said optimizer means, to said controller means, and to said control means for summing each first output signal and the second output signal to thereby generate signals representing each aforesaid regulatable set point.
  • control system of claim 1 further characterized in that said regulating means includes means to regulate the heat input to said reaction zones.
  • control system of claim 1 further characterized in that the conversion level of said reaction zones is determined by a function of:
  • control system of claim 1 further characterized in that the conversion level of said reaction zones is determined by the octane rating of said effluent.
  • a method of controlling the operation of at least two serially connected reaction zones comprising the steps of:
  • step (c) determining a performance index output signal from the signal derived from step (c);
  • step (d) optimizing the performance of said reaction zones by analyzing the output signal derived from step (d) and determining a first output signal necessary to approach an optimum performance of said reaction zones;
  • step (f) is derived from the conversion level determined by the octane rating of said effluent.
  • reaction severity is regulated by regulating the heat input to each reaction zone.
  • step (c) determining a performance index output signal from signals (1), (2), and (3) of step (c), the value of said performance index output signal being given by a function of:
  • step (c) determining the total conversion level from signals (3) and (4) of step (c) the value of said total conversion level being given by a function of:
  • step (f) determining a second output signal whose value is determined by the comparison of a desired total conversion level of said reaction zone to the actual total conversion level of each reaction zone determined in step (f);
  • step (e) summing each of the first output signals of step (e) with the second output signal of step (g) to thereby generate each aforesaid regulatable set point signal.
  • step (a) includes regulating the input of superheated steam to said reaction zones.
  • step (c) optimizing the performance of the reaction zones by analyzing signal (1) of step (c) and determining a first output signal necessary for each reaction zone to approach an optimum performance of said reaction zones;
  • step (c) determining a second output signal whose value is determined by the comparison of the desired octane value of the liquid yield and the octane value determined in step (c);
  • step (d) summing each of the first output signals of step (d) with the second output signal of step (b) to thereby generate each aforesaid regulatable set point signal.

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  • Chemical & Material Sciences (AREA)
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  • Chemical Kinetics & Catalysis (AREA)
  • Oil, Petroleum & Natural Gas (AREA)
  • Engineering & Computer Science (AREA)
  • General Chemical & Material Sciences (AREA)
  • Production Of Liquid Hydrocarbon Mixture For Refining Petroleum (AREA)
  • Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
  • Physical Or Chemical Processes And Apparatus (AREA)
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Cited By (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3917931A (en) * 1974-05-03 1975-11-04 Texaco Inc Means and method for controlling an absorber system
US3937747A (en) * 1974-04-18 1976-02-10 Atlantic Richfield Company Balancing adiabatic reactors
US3948603A (en) * 1974-05-10 1976-04-06 Universal Oil Products Company Control system for HF alkylation
US3969078A (en) * 1974-05-10 1976-07-13 Universal Oil Products Company HF Alkylation reaction temperature control system
US4092722A (en) * 1976-10-18 1978-05-30 Phillips Petroleum Company Fluid catalytic cracking with automatic temperature control
US4251503A (en) * 1978-09-19 1981-02-17 Erco Industries Limited Efficiency control system for chlorine dioxide plants
US4318178A (en) * 1980-05-28 1982-03-02 Phillips Petroleum Co. Control of a cracking furnace
US4371944A (en) * 1981-01-16 1983-02-01 Phillips Petroleum Company Ethylene process control
US5091075A (en) * 1990-07-06 1992-02-25 Uop Reforming process with improved vertical heat exchangers
US20080110801A1 (en) * 2006-11-09 2008-05-15 Leon Yuan Process For Heating A Hydrocarbon Stream Entering A Reaction Zone With A Heater Convection Section
US7740751B2 (en) 2006-11-09 2010-06-22 Uop Llc Process for heating a stream for a hydrocarbon conversion process
US20100243521A1 (en) * 2009-03-31 2010-09-30 Peters Kenneth D Fired Heater for a Hydrocarbon Conversion Process
US20120043053A1 (en) * 2010-08-20 2012-02-23 Lockheed Martin Corporation Catalytic alcohol dehydrogenation heat sink for mobile application
US20200115641A1 (en) * 2018-10-15 2020-04-16 Uop Llc Dehydrogenation process having improved run time
US11021657B2 (en) 2018-04-26 2021-06-01 Uop Llc Process and apparatus for a convection charge heater having a recycle gas distributor

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
NL190151C (nl) * 1976-03-26 1993-11-16 Schoeller & Co Ag A Werkwijze voor het vervaardigen van een kunststofpallet.
JPS57176250U (es) * 1981-04-30 1982-11-08
JPS6270803U (es) * 1985-10-25 1987-05-06
RU2486227C1 (ru) * 2012-05-14 2013-06-27 Государственное унитарное предприятие Институт нефтехимпереработки Республики Башкортостан (ГУП ИНХП РБ) Способ управления процессом каталитического риформинга

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3257363A (en) * 1961-05-22 1966-06-21 Phillips Petroleum Co Control of the composition of a reaction mixture
US3321280A (en) * 1964-06-26 1967-05-23 Exxon Research Engineering Co Computer control method for production of butyl rubber
US3402212A (en) * 1966-07-18 1968-09-17 Universal Oil Prod Co Dehydrogenation of ethylbenzene to styrene
US3458691A (en) * 1958-12-29 1969-07-29 Universal Oil Prod Co Process control system
US3497449A (en) * 1966-05-17 1970-02-24 Mobil Oil Corp Controlling a continuous process by concentration measurements
US3594559A (en) * 1968-06-26 1971-07-20 Phillips Petroleum Co Process control for polymerization control system having equation updating feedback networks

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3458691A (en) * 1958-12-29 1969-07-29 Universal Oil Prod Co Process control system
US3257363A (en) * 1961-05-22 1966-06-21 Phillips Petroleum Co Control of the composition of a reaction mixture
US3321280A (en) * 1964-06-26 1967-05-23 Exxon Research Engineering Co Computer control method for production of butyl rubber
US3497449A (en) * 1966-05-17 1970-02-24 Mobil Oil Corp Controlling a continuous process by concentration measurements
US3402212A (en) * 1966-07-18 1968-09-17 Universal Oil Prod Co Dehydrogenation of ethylbenzene to styrene
US3594559A (en) * 1968-06-26 1971-07-20 Phillips Petroleum Co Process control for polymerization control system having equation updating feedback networks

Cited By (18)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3937747A (en) * 1974-04-18 1976-02-10 Atlantic Richfield Company Balancing adiabatic reactors
US3917931A (en) * 1974-05-03 1975-11-04 Texaco Inc Means and method for controlling an absorber system
US3948603A (en) * 1974-05-10 1976-04-06 Universal Oil Products Company Control system for HF alkylation
US3969078A (en) * 1974-05-10 1976-07-13 Universal Oil Products Company HF Alkylation reaction temperature control system
US4092722A (en) * 1976-10-18 1978-05-30 Phillips Petroleum Company Fluid catalytic cracking with automatic temperature control
US4251503A (en) * 1978-09-19 1981-02-17 Erco Industries Limited Efficiency control system for chlorine dioxide plants
US4318178A (en) * 1980-05-28 1982-03-02 Phillips Petroleum Co. Control of a cracking furnace
US4371944A (en) * 1981-01-16 1983-02-01 Phillips Petroleum Company Ethylene process control
US5091075A (en) * 1990-07-06 1992-02-25 Uop Reforming process with improved vertical heat exchangers
US20080110801A1 (en) * 2006-11-09 2008-05-15 Leon Yuan Process For Heating A Hydrocarbon Stream Entering A Reaction Zone With A Heater Convection Section
US7740751B2 (en) 2006-11-09 2010-06-22 Uop Llc Process for heating a stream for a hydrocarbon conversion process
US20100243521A1 (en) * 2009-03-31 2010-09-30 Peters Kenneth D Fired Heater for a Hydrocarbon Conversion Process
US8282814B2 (en) 2009-03-31 2012-10-09 Uop Llc Fired heater for a hydrocarbon conversion process
US20120043053A1 (en) * 2010-08-20 2012-02-23 Lockheed Martin Corporation Catalytic alcohol dehydrogenation heat sink for mobile application
US8961891B2 (en) * 2010-08-20 2015-02-24 Lockheed Martin Corporation Catalytic alcohol dehydrogenation heat sink for mobile application
US11021657B2 (en) 2018-04-26 2021-06-01 Uop Llc Process and apparatus for a convection charge heater having a recycle gas distributor
US20200115641A1 (en) * 2018-10-15 2020-04-16 Uop Llc Dehydrogenation process having improved run time
US11186784B2 (en) * 2018-10-15 2021-11-30 Uop Llc Dehydrogenation process having improved run time

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SU710522A3 (ru) 1980-01-15
BR7203287D0 (pt) 1973-05-31
SE384033B (sv) 1976-04-12
EG10932A (en) 1976-10-31
GB1384916A (en) 1975-02-26
CA984858A (en) 1976-03-02
FR2138943A1 (es) 1973-01-05
AU4231772A (en) 1973-11-22
PL82832B1 (es) 1975-10-31
AU471086B2 (en) 1976-04-08
FR2138943B1 (es) 1975-06-13
IT958026B (it) 1973-10-20
DE2224637A1 (de) 1972-11-30
ES403086A1 (es) 1975-04-16

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