CN102341483B

CN102341483B - Process for preventing metal catalyzed coking

Info

Publication number: CN102341483B
Application number: CN201080010494.1A
Authority: CN
Inventors: K·A·库奇; C·D·戈斯林
Original assignee: Universal Oil Products Co
Current assignee: Honeywell UOP LLC; Universal Oil Products Co
Priority date: 2009-03-04
Filing date: 2010-02-01
Publication date: 2014-02-26
Anticipated expiration: 2030-02-01
Also published as: BRPI1009534A2; WO2010101686A3; JP2012519747A; RU2505584C2; RU2011140159A; WO2010101686A2; CN102341483A; JP5607082B2

Abstract

A process and apparatus is disclosed in which a sulfiding agent is added to a catalytic conversion reactor to prevent metal catalyzed coking. The catalytic reactor may be downstream from a first fluid catalytic cracking reactor that provides C10- hydrocarbons as feed to the downstream catalytic reactor.

Description

The method of the coking of prevention metal catalytic

Technical field

Generally, the present invention relates to manufacture the apparatus and method of the product (for example light olefin, comprises propylene) needing.

Background technology

Fluid catalystic cracking (FCC) is a kind of catalytic hydrocarbon conversion method, contacts and carries out by making compared with heavy hydrocarbon in fluidized reaction zone with catalytic particulate material.Reaction in catalytic cracking is different from hydrocracking, is in the situation that do not exist the outer hydrogenation of significant quantity or hydrogen consumption to carry out.Along with cracking reaction is carried out, the height carbonaceous material that is known as coke of significant quantity is deposited on catalyzer, provide coking or spent catalyst.Gaseous light product is separated with spent catalyst in reactor.Can for example, with rare gas element (steam), to spent catalyst, impose stripping, the hydrocarbon matter gas of holding back with stripping from spent catalyst.In regeneration zone operation, use oxygen high temperature regeneration, burn off coke from pass through steam stripped spent catalyst.Can produce various products by this method, comprise gasoline product and/or lighter products, for example propylene and/or ethene.

In these class methods, can use single reactor or double-reactor.Although use double-reactor device may cause extra fund cost, can move one of reactor, for example, to regulate the maximized condition of product (light olefin, comprises propylene and/or ethene) that makes.

In one of reactor, make product yield maximize normally favourable.In addition, may wish to make from a reactor, can recirculation for example return another reactor, to produce the product maximum production of required product (propylene).

A large amount of focuses of past FCC technical development are over several years that Propylene Selectivity is maximized.This orders about most of FCC technical licensing side exploitation double lifting leg FCC technology, wherein original raw material (being generally VGO) is sent into a riser tube, and by C _10-subsidiary riser is returned in recirculation flow or its any cut recirculation.Thus, main riser tube and subsidiary riser can move with different mode, to promote the clean yield of most overall selectivity.In typical operations, it is violent that the operation of main riser tube is not so good as subsidiary riser.The operation of subsidiary riser is much violent, for example, promote to form light olefin, butylene, propylene and ethene---comparatively high temps in 538 ° to 593 ℃ (1000 ° to 1100 °F) typical ranges and be less than 138kPa (definitely) (20psia) compared with low hydrocarbon partial pressure, promoted the formation of light olefin.The charging of subsidiary riser can be FCC recirculation material or from the C of other technique unit _10-material.

The commercialization of double lifting leg technology is all existed to the problem of the excessive coking in subsidiary riser in the operation that petroleum naphtha is recycled to subsidiary riser, this causes the limited service ability of these methods.Under known case, must shut down and remove coke before operation only limit to move several weeks but not the several months.Therefore, the catalytic cracking double-reactor device of the excessive coking that can avoid in subsidiary riser need to be provided.

summary of the invention

We have found that, the excessive coking in auxiliary reactor is owing to the coking (MCC) of metal catalytic.MCC is suppressed in conventional FCC unit, because fully there is sulphur thing class in the hydrocarbon charging of FCC apparatus, they can be decomposed to form hydrogen sulfide in FCC riser tube.Then hydrogen sulfide makes the active metal passivation in FCC apparatus.We propose when the hydrogen sulfide existing is not enough to suppress MCC, vulcanizing agent to be added to the method and apparatus in FCC riser tube or other reactor.Sulphur thing class in vulcanizing agent provides with hydrogen sulfide form, or provides hydrogen sulfide source by decomposition, release or other chemical reaction, and then it form metallic sulfide layer on the inner metal surface of reactor internal components.This metallic sulfide layer separates to suppress coking by the active metal site on gas phase coke precursors and internal surface.

accompanying drawing explanation

This accompanying drawing is schematic diagram of the present invention.

embodiment

MCC is characterised in that, carbon solid deposits and developing in surpassing the technique of 400 ℃ in hot metal surface, and the highest fibrous carbon forms speed in the scope of 550 ° to 600 ℃.MMC can be thermolysis or by the result of the reaction of active metal catalysis, and to many commercial process, comprises the catalytic steam reforming of methane, the steam cracking of paraffinic feed and the technique that relates to Carbon monoxide disproportion reaction have remarkably influenced.Be well known that, some metal can be by improving total MCC sedimentation rate by thread and the sedimental growth catalysis of graphite-like.Iron, cobalt and nickel and the alloy that contains these metals show the high catalytic activity to carbon laydown.Total catalyzed reaction approach of MCC is conventionally considered to ethene, propylene or butylene and is adsorbed onto on metallic surface.The light olefin being adsorbed is further dehydrogenation then, changes into aromatic hydrocarbons and alkylaromatic hydrocarbon, and their further condensations are until form coke.

Typical case FCC reaction is carried out in the scope of 500 ° to 600 ℃, and this is corresponding to the highest response speed that forms fibrous carbon.Be confirmed to be and promote the most activated metal of MCC to be present in FCC apparatus.The reactive hydrocarbon thing class that promotes fibrous carbon to form is ethene, propylene and butylene, and they are the target products from high propylene FCC production technology.Therefore, we believe, the coking problem in auxiliary FCC riser tube technique is owing to MCC.

Past is not yet observed MCC in FCC operation.Most of FCC apparatus processing is containing the raw material of significant quantity sulphur (common 0.1 to 1.0 % by weight).The sulphur existing in FCC charging resolves into hydrogen sulfide, and it is adsorbed on metallic surface, forms metallic sulfide layer, and the active metal site on gas phase coke precursors and FCC reactor internal surface is separated, and alleviates thus coking.We have found that, in recirculation flow, in the naphtha feed in being recycled to auxiliary FCC riser tube, conventionally do not have the hydrogen sulfide by original FCC charging cracking is generated.Organosulfur priority allocation in elementary FCC product is to the coke in hydrogen sulfide and reaction product, and then priority allocation is in heavier product, and minimum sulphur is stayed in petroleum naphtha and liquefied petroleum gas (LPG) (LPG).In the subsidiary riser of processing petroleum naphtha, petroleum naphtha not containing pollutent sulphur, causes the sulfide stratification on metal in subsidiary riser to be not enough to prevent MCC substantially.Even if there is sulphur in petroleum naphtha, unless it is the form that will thermolysis forms hydrogen sulfide, otherwise it does not form the layer of the active metal passivation that makes to cause MCC.

We propose to add vulcanizing agent in catalyticreactor, to prevent that MCC from causing chronic coke problem in auxiliary reactor.Vulcanizing agent can be hydrogen sulfide or the organosulfur compound that resolves into hydrogen sulfide in catalyzed conversion environment, particularly fluid catalystic cracking environment.Can before amine is processed, send in the dry gas of auxiliary reactor hydrogen sulfide is being provided.Also can be by adding commercially available SO in the catalyst inventory to circulation _xremove additive (the oxidation magnalium for example with spinel structure) hydrogen sulfide is provided.This additive adsorbs SO in the well-oxygenated environment of revivifier _x, and in the reducing environment of reactor riser desorb hydrogen sulfide.But, in the second reactor, use SO _xadditive provides the technical capacity height of sufficient hydrogen sulfide content to depend on the sulphur content of the raw material of sending into the first reactor.Preferred organosulfur source comprises commercially available vulcanizing agent, methyl sulphur for example, and for example methyl-sulfide (DMS) or dimethyl disulfide (DMDS), mercaptan and polysulfide, they are used as the vulcanizing agent of hydrotreater and pyrolysis oven traditionally in industrial practice.These organosulfur vulcanizing agents are degraded into hydrogen sulfide in fluid catalystic cracking and other reaction environment.Sulfur crude in FCC product, for example LCO, HCO and CSO, be not preferred vulcanizing agent, because they estimate that not effectively thermolysis produces the hydrogen sulfide that makes the required amount of active metal passivation.But under certain conditions, these heavy FCC products may be effective.Lighter FCC product, for example petroleum naphtha and LPG, if therefrom do not remove sulfide, may be also effective vulcanizing agent under certain conditions.

Preferably, hydrogen sulfide containing dry gas is added in fluidizing gas distribution device, or as atomization dispersion medium, add in the feed distributor of riser reactor.This organosulfur vulcanizing agent can add in fluidizing gas distribution device, or preferably in any position of feed distributor upstream, adds in feed system.Maximum sulphur speed is not limit, but with respect to the fluid existing in reactor, is 20 to 2000wppm suitably, and preferably 50 to 500wppm.Because coking starts very fast, so this vulcanizing agent is answered continuous adding, sulfide continuous adsorption and desorb from active metal.

Can be with reference to four component representation the present invention: main reactor or the first reactor 10, revivifier 60, product distillation stage 90 and the second reactor 170.Many structures of the present invention are all possible, but describe by way of example in this article specific embodiments.For implementing all other possible embodiments of the present invention, be considered in protection scope of the present invention.For example, if the first and second reactors 10,170 are not FCC reactors, one of revivifier 60 and product distillation stage 90 or both can be optional.In addition, can in single FCC reactor 170, specifically implement the present invention.

Accompanying drawing shows the first reactor 10, and it can be the FCC reactor that comprises the first reactor riser 12 and the first reactor vessel 20.Revivifier catalyst tube 14 is communicated with the first reactor riser 12 upstreams, means that material stream can be from revivifier catalyst tube 14 to first reactor riser 12.Be communicated with and refer to that between institute's column region, can realize material flows.Revivifier catalyst tube 14 transfers to reactor riser 12 from revivifier 60 through regenerated catalyst entrance by regenerated catalyst, and its speed is regulated by control valve 16.Fluidizing medium, for example, from the steam of divider 18, upwards pushes through the first reactor riser 12 by regenerated catalyst stream with high-density relatively.A plurality of feed distributors 22 that are communicated with the first reactor riser 12 upstreams are by the first hydrocarbon charging 8, preferably for example, together with inertia atomizing gas (steam), injection is through mobile catalyst pellets subflow, with by hydrocarbon feed distribution in the first reactor riser 12.When hydrocarbon charging contacts in the first reactor riser 12 with catalyzer, heavier hydrocarbon charging cracking produces lighter gaseous state first cracking product, and conversion coke and pollutent coke precursors are deposited on catalyst particle to produce coked catalyst.

The hydrocarbon feed of conventional FCC raw material and higher is the first suitable charging 8 of a FCC reactor.Modal this conventional raw material be " vacuum gas oil " (VGO), that it is normally made by the vacuum fractionation of long residuum, to there are 343 ° to 552 ℃ (650 ° to 1025 °F) boiling ranges hydrocarbon material.The heavy metal contamination that this cut conventionally contains low coke precursors and can pollute catalyzer.The applicable heavy hydrocarbon feedstocks of the present invention comprises from crude oil heavy still bottoms, heavy bitumen crude oil, shale oil, tar sand extract, diasphaltene residue, coal liquefaction products, normal pressure and vacuum decompression crude oil.Heavy feed stock of the present invention also comprises that the mixture of above-mentioned hydrocarbon and above-mentioned enumerating are not comprehensive.Conventionally, the first charging 8 has the temperature of 140 ° to 320 ℃.In addition, also can put the charging that downstream adds additional content in initial charge.

The first reactor vessel 20 is communicated with the first reactor riser 12 downstreams, this means that material stream can be from the first reactor riser 12 to first reactor vessels 20.The gaseous product hydrocarbon obtaining and the mixture of spent catalyst continue to make progress through the first reactor riser 12, and are received in the first reactor vessel 20, at this spent catalyst and gaseous state product separation.Pair of separated arm 24 can tangentially and flatly be discharged into the mixture of gas and catalyzer separation vessel 28 from the first reactor riser 12 tops through one or more outlets 26 (only showing), and it is separated with the part of catalyzer that separation vessel 28 carries out gas.Transmitting catheter 30 is sent hydrocarbon vapour (comprising by steam stripped hydrocarbon), stripping medium and the catalyzer carried secretly into the one or more cyclonic separators 32 in the first reactor vessel 20, and cyclonic separator 32 is separated with hydrocarbon gaseous product stream by spent catalyst.Separation vessel 28 parts are arranged in the first reactor vessel 20, and can be regarded as a part for the first reactor vessel 20.Gas duct 34 is delivered to the collection plenum chamber 36 in the first reactor vessel 20 by the separated hydrocarbon stream from cyclonic separator 32, to lead to product circuit 88 via outlet nozzle 38, and finally enters product distillation stage 90 to reclaim product.Dipleg 40 is discharged to catalyzer in the lower bed 42 the first reactor vessel 20 from cyclonic separator 32.With the catalyzer of absorption or the hydrocarbon carried secretly, can finally from lower bed 42, be passed in the opening 46 of delimiting the wall of separation vessel 28 and pass into optional stripping stage 44.Catalyzer separated in separation vessel 28 can directly pass in optional stripping stage 44 via bed 48.Fluidisation divider 50 is delivered to stripping stage 44 by inertia fluidizing agent (normally steam).Stripping stage 44 contains baffle plate 52 or miscellaneous equipment, to promote the contact between stripping gas and catalyzer.Stripped spent catalyst leaves the stripping stage 44 of the separation vessel 28 of the first reactor vessel 20, and it is carried secretly or the concentration of the hydrocarbon that adsorbs when entering or while not yet passing through stripping.Spent catalyst (preferably through stripped spent catalyst) leaves the separation vessel 28 of the first reactor vessel 20 through spent catalyst conduit 54, and passes into revivifier 60 with the speed being regulated by guiding valve 56.

The first reactor riser 12 can be moved at any suitable temperature, is 150 ° to 580 ℃, the preferably temperature operation of 520 ° to 580 ℃ conventionally at leg outlet 24 places.In an exemplary, may need higher riser temperature, for example at leg outlet 24 places, be not less than 565 ℃, and 69 to 517kPa (gauge pressure) (10 to 75psig), but be conventionally less than 275kPa (gauge pressure) pressure (40psig).Based on catalyzer with enter the weight of the feed hydrocarbon of riser tube bottom, this catalyzer and oily ratio can be maximum 30: 1, but are generally 4: 1 to 10: 1, and can be 7: 1 to 25: 1.Conventionally in this riser tube, do not add hydrogen.The steam that equals 2 to 35 % by weight of charging can be sent into the first reactor riser 12 and the first reactor vessel 20.But conventionally, in order to obtain maximum gasoline output, steam ratio is 2 to 7 % by weight, in order to obtain maximum light olefin output, steam ratio is 10 to 15 % by weight.The mean residence time of catalyzer in riser tube can be less than 5 seconds.

Catalyzer in the first reactor 10 can be single catalyzer or the mixture of different catalysts.Conventionally, this catalyzer comprises two kinds of components or catalyzer, i.e. the first component or catalyzer and second component or catalyzer.At for example US 7,312, this catalyst mixture is disclosed in 370B2.Conventionally, the first component can comprise any well-known catalysts of using in FCC field, for example active amorphous clays type catalyzer and/or high activity, crystalline molecular sieve.Zeolite can be used as the molecular sieve in FCC technique.Preferably, the first component comprises large pore zeolite (for example y-type zeolite), activated alumina material, adhesive material (comprising silicon-dioxide or aluminum oxide) and inert filler (for example kaolin).

Conventionally, the zeolite molecular sieve that is suitable for the first component has large mean pore size.Conventionally, there is wide-aperture molecular sieve and there is the hole that is greater than 0.7 nanometer in effective diameter perforate, described perforate by being greater than 10, the ring of common 12 yuan limits.The pore size index of macropore can be higher than 31.Suitable large pore zeolite component can comprise synthetic zeolite, for example X and Y zeolite, mordenite and faujusite.A part for the first component, zeolite for example, can have rare earth metal or the rare-earth oxide of any appropriate amount.

Second component can comprise mesopore or the more zeolite catalyst of fine porosity, for example MFI zeolite, for example at least one in ZSM-5, ZSM-11, ZSM-12, ZSM-23, ZSM-35, ZSM-38, ZSM-48 and other analogous material.The zeolite of the mesopore that other is suitable or more fine porosity comprises ferrierite and erionite.Preferably, second component has mesopore in the matrix of being dispersed in or the zeolite of fine porosity more, and described matrix comprises adhesive material, for example silicon-dioxide or aluminum oxide, and inert filler material, for example kaolin.Second component also can comprise some other active materials, for example β zeolite.These compositions can have 10 to 50 % by weight or larger crystalline zeolite content and the matrix material content of 50 to 90 % by weight.The component that contains 40 % by weight crystalline zeolite material is preferred, can use those with higher crystalline zeolite content.Conventionally, mesopore and more the zeolite of fine porosity be characterised in that have be less than or equal to the active porosity opening diameter, 10 yuan of 0.7 nanometer or still less unit ring and be less than 31 pore size index.Preferably, the second catalyst component is the MFI zeolite with the silica alumina ratio that is greater than 15, is preferably greater than 75.In an exemplary, silica alumina ratio can be 15: 1 to 35: 1.

Total mixture in the first reactor 10 can contain the second component of 1 to 25 % by weight, and mesopore is to aperture crystalline zeolite, and it is preferred being more than or equal to 1.75 % by weight second components.When second component contains 40 % by weight crystalline zeolites and surplus, be adhesive material, inert filler (for example kaolin) and optionally during active oxidation al composition, this mixture can contain 4 to 40 % by weight the second catalyzer, and preferred content is at least 7 % by weight.The first component can form the surplus of this catalyst composition.In some preferred embodiments, in this mixture, the relative proportion of the first and second components can significantly not change in whole the first reactor 10.As the mesopore of the second component of this catalyst mixture or more the high density of the zeolite of fine porosity can improve the selectivity to light olefin.In an exemplary, this second component can be ZSM-5 zeolite, and described mixture can comprise 4 to 10 % by weight ZSM-5 zeolites, does not comprise any other component, for example tackiness agent and/or filler.

Revivifier 60 is communicated with the first reactor vessel 20 downstreams.In revivifier 60, by coke, for example, contact with oxygen-containing gas (air), burn off coke from be transported to this part spent catalyst revivifier 60, to provide regenerated catalyst.Revivifier 60 can be the revivifier of burner types as shown in the drawing, and it can use and mix turbulent bed-condition of fast fluidization so that spent catalyst holomorphosis in highly efficient regeneration device 60.But other revivifier and other flow condition may be applicable to the present invention.Spent catalyst conduit 54 is sent into spent catalyst first or the lower chambers 62 of being delimited by outer wall through spent catalyst entrance.Conventionally the carbon that contains 0.2 to 2 % by weight from the spent catalyst of the first reactor vessel 20, it exists with coke form.Although coke mainly consists of carbon, it may contain 3 to 12 % by weight hydrogen and sulphur and other material.Containing oxygen combustion gases (being generally air), through conduit, enter the lower chambers 62 of revivifier 60 and distributed by divider 64.When combustion gases enter lower chambers 62, its spent catalyst of entering from spent catalyst conduit 54 of contact, and under fast fluidization stream condition with this catalyzer of combustion gases surface velocity elevate a turnable ladder in may the lower chambers 62 of at least 1.1 meter per seconds (3.5 feet per second).In one embodiment, lower chambers 62 can have the superficial gas velocity of density of catalyst and 1.1 to 2.2 meter per seconds (3.5 to 7 feet per second) of 48 to 320 kilograms per cubic meter (3 to 20 pounds/cubic feet).Oxygen contact spent catalyst in combustion gases, and burn carbonaceous sediment to make at least partly this catalyst regeneration and to generate flue gas from this catalyzer.

The mixture of catalyzer and combustion gases rises in lower chambers 62, the transmission lifting pipeline section 68 through conical butt transition section 66 to lower chambers 62.Promote pipeline section 68 and delimit a pipe, this pipe is preferably cylindrical, and preferably from lower chambers 62, extends upward.The mixture of catalyzer and gas is to advance than superficial gas velocity high in lower chambers 62.The raising of gas velocity is because lower chambers 62 cross-sectional areas with transition section 66 belows are compared, and promotes pipeline section 68 cross-sectional areas and reduces.Therefore, superficial gas velocity surpasses 2.2 meter per seconds (7 feet per second) conventionally.Promote pipeline section 68 and can there is the density of catalyst that is less than 80 kilograms per cubic meter (5 pounds/cubic feet).

Revivifier 60 also comprises top or the second Room 70.The mixture of catalyst particle and flue gas is discharged into upper chamber 70 from promoting the top of pipeline section 68.Regenerated catalyst can substantially fully leave the top that transmission promotes pipeline section 68, but the layout that the catalyzer of partial regeneration leaves from lower chambers 62 is also feasible.Discharge is by most of regenerated catalyst tripping device 72 separated with flue gas implemented.In one embodiment, along promoting ellipsoidal head the adverse current of pipeline section 68 to catalyzer and the gas percussion lifting pipeline section 68 at upper reaches.Then catalyzer and gas leave through the exhaust outlet of the downward guiding of tripping device 72.The reversion of the unexpected loss of momentum and downstream is fallen in fine and close catalyst bed 74 most of heavier catalyzer, and makes lighter flue gas and be still entrained in the rising in chamber 70 up of small portion catalyzer wherein.

Cyclonic separator

75,76 further makes catalyzer separated with ascending gas, and catalyzer is deposited in fine and close catalyst bed 74 through dipleg 77,78.Flue gas leaves

cyclonic separator

75,76 through gas duct, and is collected in plenum chamber 82, to lead to the outlet nozzle 84 of revivifier 60, and may pass into flue gas or power recovery system (not shown).Density of catalyst in fine and close catalyst bed 74 remains in the scope of 640 to 960 kilograms per cubic meter (40 to 60 pounds/cubic feet) conventionally.Fluidisation conduit is delivered to fine and close catalyst bed 74 by fluidizing agent (being generally air) through fluidisation divider 86.In one embodiment, in order to accelerate the coke burning in lower chambers 62, the hot regenerated catalyst of the fine and close catalyst bed 74 from upper chamber 70 can be recycled in lower chambers 62 via recycling pipe 80.

With respect to every kilogram of coke being removed, revivifier 60 may need 14 kg air conventionally, to obtain holomorphosis.When more multi-catalyst is reproduced, can in the first reactor 10, process more substantial charging.Revivifier 60 has the temperature of 594 ° to 704 ℃ (1100 ° to 1300 °F) conventionally in lower chambers 62, has up the temperature of 649 ° to 760 ℃ (1200 ° to 1400 °F) in chamber 70.Regenerated catalyst pipe 14 is communicated with revivifier 60 downstreams.Regenerated catalyst from fine and close catalyst bed 74 is transmitted back to first reactor riser 12 from revivifier 60 through control valve 16 by regenerated catalyst pipe 14, and at this, along with FCC technique continues, it contacts charging again.

In addition,, in a desirable embodiment, the first reactor 10 can move under low hydrocarbon partial pressure.Conventionally, low hydrocarbon partial pressure can facilitate light olefin to produce.Correspondingly, the pressure in the first reactor riser 12 can be for 170 to 250kPa, and hydrocarbon partial pressure is 35 to 180kPa, and preferably 70 to 140kPa.Use charging 10 to 55 % by weight, preferably to 15 % by weight the steam of amount as thinner, can realize relatively low hydrocarbon partial pressure.Can use other thinner (for example dry gas) to reach equivalent hydrocarbon partial pressure.

From the first cracking product in the circuit 88 of the first reactor 10 (it does not contain catalyst particle relatively, and comprises stripping fluid), through outlet nozzle 38, leave the first reactor vessel 20.Before fractionation, can impose additional processing to the first cracking product stream in circuit 88, to remove thin catalyst particle or further to process this stream.Circuit 88 is sent to product distillation stage 90 by first cracking product stream, and distillation stage 90 can comprise king-tower 100 and gas enriching section 114 in one embodiment.From king-tower 100, extract multi-products.In this case, king-tower 100 reclaims and comprises unstable gasoline and the lighter products overhead streams of lighter-than-air gas more in tower top circuit 102.Overhead streams in tower top circuit 102 is condensation cooling in water cooler 106 in condenser 104 before entering receptor 108.Circuit 110 takes out light exhaust flow from receptor 108.This waste gas contains LPG and dry gas.This dry gas contains hydrogen sulfide, and it can serve as vulcanizing agent.At the bottom of the tower of petroleum naphtha, liquid current through line 112 leaves receptor 108.Circuit 110 and 112 all can be sent to gas concentration section 114.In gas concentration section 114, can separated much stream, for example by fractionation, come separatedly, produce light olefin circuit 116, light naphthar circuit 118 and dry gas circuit 120.Dry gas stream can mainly be condensed into hydrogen sulfide stream, can be maybe a part of more fully expecting stream, but is represented by dry gas circuit 120.Recirculation dry gas vulcanizing agent circuit 122 extracts at least a portion dry gas stream, to send into dry gas mix sulphur agent circuit 124 and/or special-purpose dry gas vulcanizing agent circuit 184.King-tower 100 also respectively via line 126,128 and 130 provide heavy naphtha stream, light cycle oil (LCO) stream and heavy cycle oil (HCO) to flow.Part material in circuit 126,128 and 130 stream is all respectively through heat exchanger 132,134 and 136 and reflux circuit 138,140 and 142 circulations, with from king-tower 100 except reducing phlegm and internal heat.Heavy naphtha, LCO and HCO flow from king-tower 100 through circuit 144,146 and 148 conveyings separately.Can via line 150 reclaim clarified oil (CO) cut from king-tower 100 bottoms.Part CO cut is through reboiler 152 recirculation, and via line 154 is returned to king-tower 100.CO current through line 156 is removed from king-tower 100.

Light naphtha fraction preferably has at C ₅in scope lower than the initial boiling point (IBP) of 127 ℃ (260 °F); 35 ℃ (95 °F), and be more than or equal to the terminal (EP) of 127 ℃ (260 °F).The boiling point of these cuts is to use the program determination be known as ASTM D86-82.A part of light naphthar stream in light naphthar circuit 118 can reclaim further process or store in circuit 156, another part in the feed lines 158 being regulated by control valve can be delivered to recirculation feed lines 166, usings and is recycled to the second reactor 170 as charging.Heavy naphtha fraction has and is equal to or higher than the IBP of 127 ℃ (260 °F) and higher than the EP of 200 ℃ (392 °F), preferably 204 ° to 221 ℃ (400 ° and 430 °F), particularly 216 ℃ (420 °F).A part of heavy naphtha stream in circuit 144 can reclaim further process or store in circuit 160, and the another part in control valve adjusting circuit 162 can be delivered to recirculation feed lines 166, usings and is recycled to the second reactor 170 as charging.LCO stream has the IBP in the EP of heavy naphtha temperature, and the EP of 260 ° to 371 ℃ (500 ° to 700 °F), preferably 288 ℃ (550 °F).HCO stream has the IBP of the EP temperature in LCO stream, and the EP of 371 ° to 427 ℃ (700 ° to 800 °F), preferably 399 ℃ (750 °F).CO stream has the IBP of the EP temperature in HCO stream, and is included in all material seething with excitement under higher temperature.

In product recovery zone 90, can carry out the more refining separated of dry gas and LPG and/or naphtha stream, to hydrogen sulfide containing dry gas is added in the hydrocarbon feed lines that contains LPG and/or naphtha stream in the second reactor 170 but not carry through independent vulcanizing agent circuit, be so also feasible.

The second reactor 170 can be the 2nd FCC reactor.Although the second reactor 170 is depicted as the 2nd FCC reactor, it should be understood that and can use any suitable reactor, for example fixed bed or fluidized-bed.The second hydrocarbon charging can be in recirculation feed lines 166 be sent into the 2nd FCC reactor through feed distributor circuit 168 and/or fluidisation feed lines 172 and fluidisation divider supply line 174.The second charging can be at least partly by C _10-hydrocarbon and preferably C ₄to C ₁₀alkene forms.Preferably, this second hydrocarbon charging mainly comprises and has 10 or the hydrocarbon of carbon atom still less.Mainly refer to and surpass 50 % by weight, preferably surpass 80 % by weight.The second charging can comprise the low any hydrocarbonaceous feed of content of the sulphur compound that resolves into hydrogen sulfide, for example from the pyrolysis oil of pyrolysis reactor, from the Fischer-Tropsch wax of fischer-tropsch reactor, from the reformate of catalytic reforming reactor, from the virgin naphtha of crude tower with from animal tallow and the vegetables oil in appropriate reaction device or source.The second charging preferably produces in the first reactor 10, fractionation be supplied to a part of first cracking product of the second reactor 170 through recirculation feed lines 166 in the king-tower 100 of product distillation stage 90.In one embodiment, this second reactor is communicated with product distillation stage 90 and/or the first reactor 10 downstreams, and this first reactor 10 is communicated with product distillation stage 90 upstreams.The second reactor 170 can comprise the second reactor riser 180.Make the second hydrocarbon charging and the catalyzer that is delivered to the second reactor 170 contact to produce cracking upgrading product, this catalyzer is that the catalyzer return pipe 176 by being communicated with the second reactor riser 180 upstreams is delivered to the second reactor 170.

The present invention considers vulcanizing agent to add in the second reactor 170 to suppress the coking of metal catalytic wherein.Recirculation dry gas vulcanizing agent circuit 122 is the dedicated vulcanization agent sources that are communicated with the second reactor riser 180 upstreams.In other words, except preventing the coking of metal catalytic, no longer dry gas and hydrogen sulfide are sent into the second reactor 170, because they do not change into the hydrocarbon product wanted and must remove from leave the upgrading product of the second reactor 170.Hydrocarbon charging and vulcanizing agent are introduced in several embodiments of the second reactor 170 shown in can be in the accompanying drawings and are carried out.

In the first embodiment, can by the feed distributor 178 that is communicated with the second reactor riser 180 upstream connected sums and feed distributor circuit 168 (it is communicated with recirculation feed lines 166 upstreams) downstream by the second hydrocarbon feed injection in the second reactor riser 180.Feed distributor circuit 168 can extract a part or all recirculation incoming flows from recirculation feed lines 166.Recirculation feed lines 166 is communicated with tower top circuit 102 downstreams of king-tower 100, and king-tower 100 is communicated with the first reactor 10 downstreams.Can regulate the feeding rate in feed distributor circuit 168 by control valve.Feed distributor 178 can be positioned at fluidisation divider 182 tops, and fluidisation divider 182 is communicated with the second reactor riser 180 upstreams.Fluidisation divider 182 for example, is supplied to the second reactor riser 180 by fluidizing agent (steam and/or light hydrocarbon), so that catalyst fluidization.In this embodiment, from the dry gas of recirculation dry gas vulcanizing agent circuit 122, can independently add in fluidisation divider 182 via the special-purpose dry gas vulcanizing agent circuit 184 being communicated with recirculation dry gas vulcanizing agent circuit 122 downstreams and bypass atomization dry gas vulcanizing agent circuit 186 bottoms in the second reactor riser 180 in fluidisation vulcanizing agent circuit 188 and fluidisation divider supply line 174.Dry gas had both served as fluidizing agent thus, served as again the vulcanizing agent in second reactor riser 180 of adding the second reactor 170 to.Recirculation dry gas vulcanizing agent circuit 122, special-purpose dry gas vulcanizing agent circuit 184 and fluidisation vulcanizing agent circuit 188 are the dedicated vulcanization agent sources that are communicated with fluidisation divider 182 and the second reactor 170 upstreams.Hydrogen sulfide containing dry gas in recirculation dry gas vulcanizing agent circuit 122, special-purpose dry gas vulcanizing agent circuit 184 and fluidisation vulcanizing agent circuit 188 also can be used as the other parts inertia fluidizing agent used of the second reactor 170.In this embodiment, the control valve in feed lines 158 and/or 162 and 168 and in vulcanizing agent circuit 122,184 and 188 can be opened, and the control valve in feed lines 172 and

vulcanizing agent circuit

124 and 186 can be closed.

In the second embodiment, when the second charging is liquid, hydrogen sulfide containing dry gas can be added in liquid the second charging in feed distributor 178, with by this liquid hydrocarbon second charging atomization with make the metal passivation in the second reactor.Recirculation dry gas vulcanizing agent circuit 122 is the dedicated vulcanization agent sources that are communicated with feed distributor 178 upstreams via atomization dry gas vulcanizing agent circuit 186.The atomization dry gas vulcanizing agent circuit 186 being communicated with special-purpose dry gas vulcanizing agent circuit 184 downstreams is supplied to dry gas the gas inlet of feed distributor 178.Can vulcanizing agent be added in the second reactor according to this embodiment, for supplementing or replace the vulcanizing agent addition manner (by adding through fluidisation divider 182) of the first embodiment.Therefore, except opening and closing in other embodiments control valve, also open the control valve in circuit 186, like this can be according to this second embodiment operation.Correspondingly, at least must open control valve in vulcanizing agent circuit 122,184 and 186 to move under this embodiment.

In the 3rd embodiment, substantially all (at least 90 % by mole) the second hydrocarbon chargings in recirculation feed lines 166 are gas phase.Conventionally, when entering the second reactor riser 180, the temperature of the second hydrocarbon charging can be 120 ° to 600 ℃, and preferably at least higher than the boiling point of these components.In this embodiment, the second hydrocarbon charging directly can be sent into fluidisation divider 182 in the second riser tube bottom, with by catalyst fluidization and send into the second reactor riser 180.In this embodiment, as shown in the drawing, open

vulcanizing agent circuit

122 and 124 and feed lines 158 and/or 162 and 172 in one or all control valves, so that the hydrogen sulfide containing dry gas in recirculation dry gas vulcanizing agent circuit 122 and dry gas mix sulphur agent circuit 124 and the light naphthar in light naphthar circuit 158 and/or the heavy naphtha in heavy naphtha circuit 162 are as the secondary feeds recirculation in recirculation feed lines 166, fluidisation feed lines 172 and fluidisation divider supply line 174, to be dispensed to riser tube by fluidisation divider 182.In this embodiment, conventionally close the valve in feed lines 168 and vulcanizing agent circuit 184,186 and 188.Dry gas should contain sufficient hydrogen sulfide, with the metal passivation of the coking in can the second reactor riser 180 of catalysis the second reactor 170.Heat exchanger 190 may be necessary in fluidisation feed lines 172, with the secondary feeds of this recirculation of vaporizing.In this embodiment, fluidisation divider supply line 174 serves as feed lines, and fluidisation divider 182 serves as feed distributor.

Hydrogen sulfide in dry gas or non-dry gas, or organosulfur additive, for example methyl sulphur, mercaptan and polysulfide, can be the appropriate addn vulcanizing agent adding in the second reactor 170.Additive sulfur agent can be in feed lines 158,162,166,168,172 or 174 or other place of the second reactor 170 upstreams add in the second charging.For example, additive sulfur agent circuit 192 can directly add vulcanizing agent in fluidisation feed lines 172.Also vulcanizing agent directly can be added in the second reactor riser 180, add in the fluidizing agent of fluidisation divider 182 upstreams or even add in the catalyzer that enters riser tube in catalyzer return pipe 176.If by SO _xscavenging agent additive adds in catalyzer, and the hydrogen sulfide being adsorbed on additive can be delivered to the second reactor 170 via pipeline 216 and catalyzer return pipe 176, makes one of catalyzer return pipe 176 and pipeline 216 or these two become vulcanizing agent circuit.Vulcanizing agent in vulcanizing agent circuit stream preferably has the hydrogen sulfide of 1000wppm at least or can in reactor environment, change into the concentration of the compound of hydrogen sulfide.Sulphur concentration with respect to the fluid in the second reactor 170 should remain at least 20wppm, preferably 50wppm at least.In riser reactor, with respect to the hydrocarbon in reactor and rare gas element, sulphur concentration should remain at least 20wppm, preferably 50wppm at least.In one embodiment, with respect to the sulphur concentration of the fluid in the second reactor, should remain on and be not more than 2000wppm, preferably be not more than 500wppm.In riser reactor, with respect to the hydrocarbon in reactor and rare gas element, sulphur concentration should remain on and be not more than 2000wppm, is preferably not more than 500wppm.

Vulcanizing agent circuit 122,124,176,184,186,188 and 192 is independent of feed lines 158 and 162.During control valve in shut-down circuit 124, circuit 166,168 and 172 is also the feed lines that is independent of vulcanizing agent circuit 122,184,186 and 188.During control valve in shut-down

circuit

124 and 172, fluidisation feed lines 172 no longer transmits charging, but fluidisation divider supply line 174 becomes the vulcanizing agent circuit that is independent of feed lines 158,162,166 and 168.Although the material stream in vulcanizing agent circuit and feed lines can mix at downstream position, these material stream is at least upstream position is separate.Correspondingly, vulcanizing agent circuit provides at the second reactor 170 upstreams and the discrete vulcanizing agent of the second hydrocarbon charging.

Conventionally, the second reactor 170 can move under the condition that hydrocarbon feedstock conversion is become to less hydrocarbon product.C _10-cracking of olefins becomes one or more light olefins, for example ethene and/or propylene.The second reactor vessel 194 is communicated with the second reactor riser 180 downstreams, to receive upgrading product and catalyzer from the second reactor riser.The mixture of gaseous state upgrading product hydrocarbon and catalyzer continues upwards to pass through the second reactor riser 180, and is received in the second reactor vessel 194, at this catalyzer and hydrocarbon gas upgrading product separation.Pair of separated arm 196 can be by the mixture of gas and catalyzer from the second reactor riser 180 tops through one or more outlets 198 (only showing), tangential and horizontal drain is to the second reactor vessel 194, the second reactor vessel 194 enforcement gases are separated with the part of catalyzer.Catalyzer can be fallen in the fine and close catalyst bed 200 in the second reactor vessel 194.After this, can be by upgrading hydrocarbon product and catalyst separating, and from the second reactor 170, take out by the outlet 204 being communicated with the second reactor 170 downstreams through upgrading product circuit 206.Upgrading product in upgrading product circuit 206 can be sent to the one or more cyclonic separators 32 in the first reactor vessel 20 of the first reactor 10.These cyclonic separators 32 can only be exclusively used in through dedicated line (not shown) from the second reactor 170 to product distillation stage 90 or the upgrading product of gas concentration section 114 particularly, or march to product distillation stage 90 together with can mixedly with the product from the first reactor riser 12 being incorporated in pipeline 88.Or the second reactor vessel 194 can contain or have one or more cyclonic separators, further separated with catalyzer with product that gaseous state is upgraded, and through upgrading product circuit 206, march to the gas concentration section 114 of product distillation stage 90.Or upgrading product circuit 206 can be delivered to circuit 88 to be delivered to the king-tower 100 of product distillation stage 90 by upgrading product.

In some embodiments, the second reactor 170 can contain the mixture of the first and second catalyst components as above.In a preferred embodiment, the second reactor 170 can contain and be less than 20 % by weight, preferably described first component of 5 % by weight and the described second component of at least 20 % by weight.In another preferred embodiment, the second reactor 170 can only contain described second component, and preferred ZSM-5 zeolite, as catalyzer.

Separated catalyzer can be regulated and be returned the second reactor riser 180 from the second reactor vessel 194 recirculation by control valve 210 through recycle catalyst pipe 208, to contact with the second charging.Optionally, catalyzer can be supplied to the second reactor 170 by the stripping stage 44 of a FCC reactor and/or through pipeline 216 by revivifier 60 (both being regulated by control valve) through pipeline 214.Pipeline 214 and 216 all can be communicated with recycle catalyst pipe 208 upstreams.Catalyzer return pipe 176 can be a part for recycle catalyst pipe 208.In one embodiment, from the catalyzer of the second reactor vessel 194, by pipeline 202, be delivered to the first reactor, be preferably delivered to stripping stage 44, and be delivered to revivifier 60 (preferably carrying) so that regeneration after stripping through spent catalyst conduit 54.Regenerated catalyst can be sent the second reactor riser 180 bottoms back to through catalyzer return pipe 176 by pipeline 216.In this embodiment, the catalyzer in the first and

second reactors

10 and 170 is mixed, and can in these two reactors, all have even composition.

In another embodiment, the second reactor 170 and revivifier 60 isolation, regenerated catalyst is only sent back to the first reactor 10, and the second reactor 170 is not sent to catalyzer revivifier 60 or from wherein receiving regenerated catalyst.In this embodiment, the second catalyst component does not keep more its activity owing to being exposed under repeated regeneration.On the contrary, the second catalyst component can be added in the second reactor 170, and the pipeline 202 that the catalyzer in the second reactor vessel 194 can be by being regulated by control valve regularly or continuous dispensing to the stripping stage 44 of the first reactor 10.The catalyzer of this distribution can with the first reactor 10 in catalyzer merge, and provide therein additional catalyst activity.The catalyzer of the alternative distribution of live catalyst, to keep the activity in the second reactor 170.

The second reactor riser 180 can be moved under any suitable condition, the temperature of 425 ° to 705 ℃ for example, the preferably temperature of 550 ° to 600 ℃ and 40 to 700kPa pressure, preferably 40 to 400kPa pressure, and best 200 to 250kPa pressure.Conventionally, the residence time of the second reactor riser 180 can be less than 5 seconds, preferably 2 to 3 seconds.At for example US2008/0035527A1 and US 7,261, exemplary riser tube and/or operational conditions are disclosed in 807B2.

Without being described in further detail, believe that those skilled in the art can use description above to make full use of the present invention.Therefore, above-mentioned preferred specific embodiments should be construed as only exemplary, but not limits by any way all the other contents of the present invention.

Hereinbefore, unless otherwise specified, all temperature by degree Celsius, all umbers and percentages.

According to description above, those skilled in the art easily determine essential characteristic of the present invention, and can in the situation that not departing from its essence and protection domain, make various change of the present invention and modification, so that it adapts to various uses and condition.

Claims

1. fluid catalystic cracking method, comprising:

Hydrocarbon charging is sent into reactor;

By catalyst transport to described reactor;

Described hydrocarbon charging is contacted with described catalyzer;

In described reactor upstream, provide the vulcanizing agent separating with described charging;

Described vulcanizing agent is added in described reactor;

Make described hydrocarbon charging be cracked into less hydrocarbon product; With

By described hydrocarbon product and described catalyst separating.

2. the fluid catalystic cracking method of claim 1, further comprises fluidization gas distribution to described reactor, and makes the described catalyst fluidization in described reactor.

3. the fluid catalystic cracking method of claim 2, further comprises to described hydrocarbon charging or adds described vulcanizing agent to described fluidizing agent, or the fluidizing agent that comprises described vulcanizing agent is provided.

4. the fluid catalystic cracking method of claim 1, is further included in first fluidized bed catalyst cracker and makes the first hydrocarbon charging cracking so that first cracking product to be provided, and provides a part of described first cracking product as described hydrocarbon charging to described reactor.

5. the fluid catalystic cracking method of claim 4, further comprises the fractionation of described first cracking product, so that described hydrocarbon charging to be provided to described reactor.

6. the fluid catalystic cracking method of claim 5, further comprise the fractionation of described first cracking product so that hydrogen sulfide containing dry gas stream to be provided, and described dry gas stream provides described vulcanizing agent.

7. the fluid catalystic cracking method of claim 1, wherein said vulcanizing agent comprises methyl sulphur, hydrogen sulfide, mercaptan and polysulfide.

8. the fluid catalystic cracking method of claim 1, further comprise sulphur concentration in the fluid making in reactor remain on 20 and 2000wppm between.

9. the fluid catalystic cracking method of claim 1, wherein said hydrocarbon charging mainly comprises and has 10 or the hydrocarbon of carbon atom still less.

10. fluidized bed catalytic cracker, it comprises:

For making hydrocarbon charging contact to generate the riser tube of product with catalyzer;

Be communicated with described riser tube with the catalyst tube to described riser tube by catalyst transport;

For transmitting the feed lines of hydrocarbon charging;

Be communicated with described hydrocarbon charging to be delivered to the feed distributor of described riser tube with described riser tube with described feed lines connected sum;

Be communicated with from described riser tube, to receive the reactor vessel of product and catalyzer with described riser tube; With

The vulcanizing agent circuit that is independent of described feed lines being communicated with described riser tube.