TWI414359B - Apparatus and process for regenerating catalyst - Google Patents

Description

Device and method for regenerating catalyst

This invention relates to a process for regenerating spent hydrocarbon conversion catalysts by combustion of coke on a catalyst in a fluidized combustion zone. In particular, the invention relates to a method of converting heavy hydrocarbons to lighter hydrocarbons and regenerating catalyst particles using a fluidized stream of catalyst particles to remove coke used to passivate the catalyst.

Fluidized Media Cracking (FCC) is a hydrocarbon conversion process that is achieved by contacting a hydrocarbon in a fluidized reaction zone with a catalyst comprising a subdivided specific material. In contrast to hydrocracking, the reaction in the crack is carried out in the absence of additional hydrocarbon or hydrogen consumption. As the cleavage reaction proceeds, a large amount of highly carbonaceous material called coke is deposited on the catalyst. One of the regeneration zone operations is high temperature regeneration from the catalyst to burn coke. The coke-containing catalyst referred to herein as a catalyst is continuously removed from the reaction zone and removed from the regeneration zone and replaced by a substantially coke-free catalyst. Fluidization of the catalyst particles by different gas streams allows the catalyst to be transported between the reaction zone and the regeneration zone. Those skilled in the art of FCC are well aware of methods for cracking hydrocarbons in a fluidized stream of a catalyst, transporting a catalyst between a reaction zone and a regeneration zone, and burning coke in a regenerator. To this end, the technology is filled in a container configuration for contacting the catalyst particles with the feed gas and the regeneration gas, respectively.

A common goal of these configurations is to maximize reactor yield while minimizing operating and equipment costs. Optimization of feedstock conversion generally requires substantially complete removal of coke from the catalyst. The substantially complete removal of coke by the self-catalyst is often referred to as complete regeneration. Complete regeneration produces a catalyst having less than 0.1% by weight and preferably less than 0.05% coke by weight. To achieve complete regeneration, the catalyst must be in contact with oxygen for a sufficient residence time to allow complete combustion.

Conventional regenerators typically include a vessel that includes a distributor inlet, a regenerated catalyst outlet, and a distributor for supplying air to the dense phase bed of the catalyst in the vessel. The cyclone removes the catalyst from the spent gas in the spent combustion gas before it leaves the regenerator vessel. U.S. Patent 4,610,851 discloses a regenerator vessel having one of two air distributors located at different levels to ensure proper distribution of combustion gases throughout the vessel. U.S. Patent 5,827,793 teaches at least two air distributors at different levels in the lower half of the dense phase bed of the catalyst to promote a reducing environment in the dense bed. U.S. Patent 4,843,051 shows two air distributor grids at different levels in a regenerative vessel to ensure adequate combustion. U.S. Patent No. 5,773,378 teaches a regenerator vessel having a lower air distributor and air entering above the lower air distributor having a catalyst.

In a dense phase catalyst bed (also known as a bubble bed), the combustion gases form a bubble that rises through one of the dense phase catalyst beds to discern the top surface. A relatively small amount of catalyst is carried in the combustion gases leaving the dense bed. Depending on the nature of the catalyst, the superficial velocity of the combustion gas is typically less than 0.3 m/s (1.0 ft/s) and the density of the dense bed is typically greater than 640 kg/m ³ (40 lb/ft ³ ). The permeate gas bypass of the mixture of catalyst and combustion gases and the catalyst is non-uniform.

One way to obtain a fully regenerated catalyst is by performing regeneration in the stage. U.S. Patent 3,958,953 describes a stepped flow system having concentric catalyst beds separated by baffles that are open to a common space for collecting spent regeneration gas and separating catalyst particles. U.S. Patent 4,299,687 teaches the use of a stepped regenerator system having one of the overlapping catalyst beds, wherein the spent catalyst particles first enter the upper dense phase fluidized bed of one of the catalysts and with the regeneration gas from the lower catalyst bed and fresh regeneration. Gas contact. After partial regeneration in the first regeneration zone, the gravity flow transports the catalyst particles into the lower catalyst bed, filling the lower catalyst bed with a fresh regeneration gas stream. A two-stage regenerator is disclosed in U.S. Patent 4,695,370 and U.S. Patent 4,664,778, each of which is performed in a separate container.

The use of a relatively dilute phase regeneration zone that can affect complete catalyst regeneration is shown in U.S. Patent 4,430,201, U.S. Patent 3,844,973, and U.S. Patent 3,923,686. These patents teach a distribution of a lower phase bed and an upper delivery zone below the combustion gases. Additional air is dispensed in the riser that provides one of the delivery zones. A two-stage system of combined relative dilution phase transport zones is shown in U.S. Patent No. 5,158,919 and U.S. Patent No. 4,272,402, which is incorporated herein by reference. Each of these patents teaches an upper dense bed in which at least a portion of the regenerated catalyst exiting the transport zone is collected.

Dilution or delivery flow jurisdictions are commonly used in FCC riser reactors. In the transport stream, the difference in velocity between the gas and the catalyst is relatively low, with very little catalyst being inversely mixed or blocked. The catalyst in the reaction zone is maintained to flow under conditions of low density and very dilute phase. The transport stream hollow column gas velocity is typically greater than 2.1 m/s (7.0 ft/s) and the density of the catalyst typically does not exceed 48 kg/m ³ (3 lb/ft ³ ). The density in one of the regenerator transport zones can approach 80 kg/m ³ (5 lb/ft ³ ). In the transport mode, the catalyst-combustion gas mixture is uniform and does not have gas voids or bubbles formed in the catalyst phase.

The intermediate phase of the dense phase, bubble bed and dilution, transporting the mobile domain is a turbulent bed and a fast fluidized jurisdiction. In a turbulent bed, the mixture of catalyst and combustion gases is non-uniform. The turbulent bed is a dense phase catalyst bed in which elongated voids of combustion gases are formed in the catalyst phase and a more difficult surface to distinguish. The catalyst and combustion gases entrained leave the bed and the catalyst density is not completely proportional to its elevation in the reactor. In a turbulent bed, the velocity of the combustion gas in the empty tower is between 0.3 m/s and 1.1 m/s (1.0 ft/s and 3.5 ft/s), and the density is usually 320 kg/m ³ and 640 kg/m. ³ (20 lb/ft ³ and 40 lb/ft ³ ).

The rapid fluidization defines a condition and a complete particle transport mode of the fluidized solid particles disposed between the turbulent beds of the particles. The fast fluidization condition is characterized by a fluidized gas velocity that is higher than the velocity of a dense phase turbulent bed, resulting in lower catalyst density and severe solid/gas contact. In a fast fluidization zone, there is a mesh transport of the catalyst caused by the upward flow of the fluidizing gas. Catalyst density in fast fluidization conditions is more sensitive to particle loading than particle loading in full particle transport mode. Therefore, it is possible to adjust the catalyst residence time to achieve the desired combustion under highly effective gas-solids mixing conditions. From the fast fluidization mode, a further increase in the velocity of the fluidizing gas will increase the rate of upward particle transport and will drastically reduce the average catalyst density until the particles move primarily in the full catalyst transport mode at a sufficient gas velocity. Thus, there is a continuation in the process of rapid fluidization from a fluidized particle bed to a pure transport mode. The velocity of a gas stream in a fast fluidized flow jurisdiction is typically between 1.1 m/s and 2.1 m/s (3.5 ft/s and 7 ft/s) and the density is typically 48 kg/m ³ and 320 kg/ m ³ (3 lb/ft ³ and 20 lb/ft ³ ).

U.S. Patent Nos. 4,849,091, 4,197,189 and 4,336,160 teach a riser combustion zone in which rapid fluidization flow conditions are maintained. The latter patent teaches a combustion chamber regenerator in which complete combustion takes place in a fast fluidized riser zone without the need to add combustion gases collected from the top of the riser to the bed.

The combustor is a type of regenerator that completely regenerates the catalyst with a relatively small amount of excess oxygen in a lower combustion chamber under rapid fluidizing flow conditions. The riser carries the regenerated catalyst and spent combustion gases to a separation chamber where significant combustion occurs. The regeneration catalyst in the separation chamber is recycled to the lower combustion phase to heat the spent catalyst to be subjected to combustion. The regenerative catalyst recycle provides heat to accelerate the combustion of the lower phase of the catalyst. The combustion chamber is advantageous due to its effective oxygen demand.

Due to the additional requirements for FCC units, the combustor vessel is required to handle more catalyst production. A greater amount of combustion gas is added to the combustion chamber vessel to burn a greater amount of catalyst. As the flow rate of the combustion gas increases, the flow rate of the catalyst between the combustion and separation chambers also increases. Therefore, unless the combustion chamber of the combustion chamber vessel is not enlarged, the residence time of the catalyst in the lower zone will be reduced, thereby reducing the thoroughness of combustion that must be achieved before the catalyst enters the separation chamber.

The present invention is directed to an arrangement for removing carbon deposits known as coke from the surface and pores of the catalyst used in the hydrocarbon conversion process. The synthetic turbulent bed in the regeneration vessel and rapid fluidization conditions ensure sufficient residence time for regeneration of the spent hydrocarbon cracking catalyst. The combustion chamber utilizes synthetic conditions to completely regenerate the catalyst. The separation chamber collects a dense phase bed of fully regenerated catalyst. The present invention can be used to increase the combustion gas production to accommodate a correspondingly increased catalyst production while still maintaining sufficient residence time of the combustion gases in contact with the catalyst.

The method and apparatus of the present invention can be implemented in an FCC unit. 1 shows an FCC unit including a reactor vessel 10 and a burner vessel 50. The burner riser 12 conveys the catalyst from the combustor vessel 50 to the reactor vessel 10 at a rate adjusted by the spool 14. Fluidizing medium, such as steam, from nozzle 16 delivers the catalyst upwardly through riser 18 at a relatively high density until a plurality of feed nozzles 20 (only one shown) are injected over the flow of fluid from the catalyst particles. The resulting mixture continues upwardly through riser tube 18 until a pair of separation arms 22 vents a mixture of gas and catalyst from the top of riser tube 18 through port 24 into detachment vessel 26, which affects the gas from the catalyst. Separation. The delivery conduit 28 carries hydrocarbon vapors comprising stripped hydrocarbons, stripping media and entrained catalyst to one or more cyclones 30 in the separator vessel 32, the separator vessel 32 separating the hydrocarbon vapor stream from the spent catalyst . The collection chamber 34 in the separator vessel 32 collects the separated hydrocarbon vapor stream from the cyclone 30 for delivery to the outlet nozzle 36 and ultimately to a fractionation recovery zone (not shown). The dip tube 38 discharges the catalyst from the cyclone 30 into a lower portion of the separator vessel 32, which ultimately feeds the catalyst and absorbed or entrained hydrocarbons over the port 42 defined by the wall of the separation vessel 26. Stripped in section 40. The catalyst separated in the separation vessel 26 directly enters the stripping section 40. The stripping section 40 contains baffles 43, 44 to promote mixing between the stripping gas and the catalyst. The stripping gas enters the lower portion of the stripping section 40 through at least one inlet 46 to one or more dispensers (not shown). The catalyst is passed through the reactor conduit 48 leaving the stripping section 40 and entering the burner vessel 50 at a rate adjusted by the spool 52.

The combustor vessel 50 utilizes a mixed turbulent bed in the high efficiency combustor chamber 54 to rapidly fluidize conditions to fully regenerate the spent catalyst. The combustor chamber 54 of the combustor vessel 50 includes three combustion zones: a turbulent zone 56, a fast fluidization zone 58, and a transfer zone 60. The reactor conduit 48 supplies the used catalyst to the combustor chamber 54 via the spent catalyst inlet chute 62 at point "A". The elliptical base 63 of the combustor chamber 54 defines a cross-sectional area at the intersection "B" with the sidewall 55 of the combustor chamber 54 below the over-catalyst inlet chute 62. The catalyst used from the reactor vessel 10 typically contains from 0.2% to 2% by weight of carbon, which is present in the form of coke. Although coke is mainly composed of carbon, it may contain from 3% to 12% by weight of hydrogen, as well as sulfur and other materials. The oxy-combustion gas (typically air) enters the combustor chamber 54 of the combustor vessel 50 at two elevations. One of the combustion gases, the first fluid enters the combustor chamber 54 at a low elevation via the low conduit 64 and is distributed by the low distributor 66 over the turbulent zone 56. The opening 68 in the low distributor 66 emits combustion gases at a vertical elevation below the entry point "A" of the catalyst entering the burner chamber 54. As the combustion gases enter the combustion zone, they contact the spent catalyst accumulated in the turbulent catalyst bed 70 in the turbulent zone 56. The combustion gases are distributed by the low distributor 66 to provide a superficial gas velocity of less than 1.1 m/s (3.5 ft/s) which is insufficient to destroy the turbulent catalytic bed 70 in the turbulent zone 56. In other words, the gas velocity from the low distributor 66 will be insufficient to carry the catalyst and remove the catalyst from the bed, thereby retaining the catalyst bed 70. The turbulent zone 56 will have a catalyst density of from 320 to 640 kg/m ³ (20 to 40 lb/ft ³ ).

A second fluid of the combustor body enters the rapid fluidization zone 58 of the combustor chamber 54 via the high conduit 72 and is distributed by the high distributor 74 across the combustor chamber 54. The opening 76 in the high distributor 74 is above the entry point "A" of the over-catalyst entering the burner vessel 50 through the over-catalyst inlet chute 62 and above the combustion gas passing through the low distributor 66. The combustion gas is emitted at a vertical elevation of the entry point of the first fluid. Thus, in an embodiment, the entry point "A" is located vertically between the high distributor 74 and the low distributor 66. In another embodiment, the combustion fluid distributed to the fast fluidization zone 58 of the combustor chamber 54 via the high distributor 74 rather than via the low distributor 66 is less. However, when the flow rate of the combustion gases from the low distributor 66 is combined with the flow rate of the combustion gases from the high distributor 74, the superficial velocity of the total combustion gases in the combustion gas chamber 54 reaches at least 1.1 m/s ( 3.5 ft/s) enters the fast fluidization zone 58 under rapid fluidized flow conditions. In an embodiment, the fast fluidization zone 58 will have a catalyst density of from 48 to 320 kg/m ³ (3 to 20 lb/ft ³ ) and from 1.1 to 2.2 m/s (3.5 to 7 ft/s). Empty tower gas velocity. A gradual transition from the turbulent zone 56 to the fast fluidization zone 58 is provided above the opening 76. In the fast fluidization zone 58, the density of the catalyst will decrease in proportion to the height.

The transition from a turbulent bed to a fluidized flow jurisdiction is not represented by a discernible bed surface. Thus, the continuous reduction of catalyst density will extend upwardly from the turbulent flow bed 70 in the combustor chamber 54. The rate at which the catalyst density decreases with the height of the combustor chamber 54 will decrease in proportion to the rate at which the catalyst is delivered to the combustor chamber 54.

In one embodiment, to accelerate combustion of coke in the combustor chamber 54, the hot regenerative catalyst from the dense phase catalyst bed 78 in the upper chamber 80 may be extended via a recirculation riser 82 that is regulated by a control valve 84. Recirculation into the combustor chamber 54. The hot regenerative catalyst enters the combustor chamber 54 via the inlet chute 86. Recirculation of the regenerative catalyst enhances the turbulent zone 56 by mixing the thermal catalyst from the dense phase catalyst bed 78 with the relatively cold catalyst used to enter the combustor chamber 54 from the reactor conduit 48. The total temperature of the catalyst and gas mixture in the medium. In addition to the use of the extended recycle riser 82, several other methods of affecting catalyst recycle can be used. For example, the catalyst can be internally transferred by an internal standpipe (not shown). The height of the particles loaded into the combustor chamber 54 can be adjusted by increasing the recirculation flow rate through the catalyst of the control valve 84 without affecting the flow rate through the catalyst for the spool 52. The regenerative catalyst may pass through the inlet chute 86 at the same elevation as the entry point "A" through the catalyst feed chute 62. However, in one embodiment, the regeneration catalyst enters the combustor chamber 54 between the low distributor 66 and the high distributor 74 to have a larger heat exchanger in the turbulent bed 70.

By distributing the combustion gases at two elevations, above and below the entry point "A" of the catalyst, more combustion gases can be added to the catalyst in the combustor chamber 54 without being immediately in the burner. Rapid fluidization flow conditions are formed in chamber 54 and turbulent bed 70 is destroyed. Thus, the transition between turbulent zone 56 and fast fluidization zone 58 may extend to near high distributor 74, at or above high distributor 74. The catalyst is used in the combustor chamber 54 to contact the combustion gases for a longer residence time. In addition, if all of the combustion gases are introduced above the entry point "A" of the over-catalyst, many of the used catalysts in the turbulent bed 70 will undergo fluidization only after longer delays and stagnation.

The catalyst and gas mixture in the fast fluidization zone 58 rises through the frustoconical transition section 90 to the delivery zone 60 in the riser section 94 of the combustor chamber 54 in a faster fluidized zone below the transition section 90. 58 or higher turbulent gas velocity in the turbulent zone 56 operates. The increased gas velocity is due to the reduced cross-sectional area of the riser section 94 relative to the cross-sectional area of the combustor chamber 54 below the transition section 90. The cross-sectional area of the riser end 94 is less than the cross-sectional area of the combustor chamber 54 at the intersection "B" below the catalyst inlet chute 62 to ensure increased superficial velocity. Therefore, the empty tower gas velocity will typically exceed 2.2 m/s (7 ft/s). Delivery zone 60 will have a lower catalyst density of less than 80 kg/m ³ (5 lb/ft ³ ).

The burner vessel 50 also includes an overlying separation chamber 100. A mixture of catalyst particles and combustion gases discarded due to oxygen consumption is discharged into the separation chamber 100 from the upper portion of the riser section 94. The substantially fully regenerated catalyst exits the top of the transport zone 60. The separation device 96 affects the discharge, and the separation device 96 separates the spent regeneration gas from most of the regenerated catalyst. Upon exiting the riser section 94, the initial separation of the catalyst minimizes the loading of the cyclone 98, 99 or other catalyst on the downstream means for substantially completely removing the catalyst particles from the spent regeneration gas, thereby reducing the overall equipment cost. Various flow devices known to those skilled in the art will perform preliminary catalyst and gas separation which will be suitable for use as separation device 96. In one embodiment, the catalyst and gas that flow up to the riser section 94 strikes the top elliptical cover 61 of the riser section 94 and recirculates. The catalyst and gas then exit through the opening of the side of the separation device 96 that is directed downwardly into the arm 97. The sudden loss of momentum and the downward flow reverse cause at least 70% and preferably 80% by weight of the heavy catalyst to fall to the dense phase catalyst bed 78, and the lighter combustion gases and the smaller portion of the catalyst remain The crucible is carried therein and rises up to the separation space 102 of the separation chamber 100.

The catalyst separated downwardly is collected in a dense phase catalyst bed 78. The catalyst density in the dense phase catalyst bed 78 is typically maintained in the range of from 640 to 960 kg/m ³ (40 to 60 lb/ft ³ ). Fluidizing conduit 106 delivers a fluidizing gas, typically air, to dense phase catalyst bed 78 via fluidizing distributor 108. Approximately no more than 2% of the total gas demand in the process enters the dense phase catalyst bed 78 via the fluidization distributor 108. The gas is added here not for combustion purposes, but only for fluidization purposes, so that the catalyst will flow away from the risers 82 and 12. The fluidizing gas added via the fluidization distributor 108 can be a combustion gas.

The combined combustion and fluidizing gas and the catalyst particles of the entrainment enter one or more separate components, such as cyclones 98, 99 which are separable gas and catalytic fines. The relatively non-catalytic spent combustion gases exit the combustor vessel 50 via the outlet conduit 110, and the recovery catalyst returns to the dense phase catalyst bed 78 via individual dip tubes 112, 113 or other similar components. 10% to 30% by weight of catalyst discharged from the combustor chamber 54 is present in the gas above the outlet of the transfer zone 60 and enters the cyclones 98, 99. The catalyst from the dense phase catalyst bed 78 is transferred back to the reactor vessel 10 via the burner riser 12 where the catalyst contacts the feed again as the FCC process continues.

The combustor chamber 54 provides a lower catalyst density jurisdiction and an extended period of intense mixing which is believed to be most efficient and characterized for high efficiency regeneration for coke combustion. Thus, the addition of combustion gases under conditions to promote high efficiency regeneration is sufficient to remove all of the coke from the catalyst entering the combustor chamber 54. The combustion gases may be delivered to the conduits 64, 72, and 106 by the same line, but in one embodiment, the feed rate to the lower conduit 64 should be greater than the feed rate to the high conduit 72.

Thus, one of the FCC reaction zones associated with the present invention can be used to treat a conventional FCC feedstock or a higher boiling hydrocarbon feed. The most common such raw material is "Vacuum Gas Oil" (VGO), which is typically a hydrocarbon having a boiling range from 343 ° to 552 ° F (650 ° to 1025 ° F) prepared by vacuum fractionation of atmospheric residues. material. This fraction is generally lower in coke precursors and heavy metal contaminants that can be used to contaminate the catalyst. The heavy hydrocarbon feedstocks to which the present invention can be applied include crude oil residue, heavy bitumen crude oil, rock oil, tar sand extract, leach residue, coal liquefaction product, atmospheric and vacuum distilled crude oil. The heavy feedstocks useful in the present invention also include mixtures of the above hydrocarbons. However, the above list is not intended to exclude the application of this method to other suitable feeds. These heavy hydrocarbon fractions are also characterized by the presence of significant metal contaminants. These metals accumulate on the catalyst and poison the catalyst by blocking the reaction site and promote excessive cleavage, thereby hindering the reaction process. Thus, in the treatment of heavy feedstocks in the present invention, it is contemplated to use passivation or other metal management procedures in the reaction zone or prior to the reaction zone.

Accordingly, one advantage of the present invention is that it allows for the regeneration of a greater number of used catalysts by exposing them to a proportionally larger amount of combustion gases without blowing the catalyst out of the regeneration zone until regeneration is complete. With regard to oxygen or air demand, the burner vessel of the present invention may typically require removal to obtain 14 kilograms of air per kilogram of coke that is fully regenerated. When more catalyst is regenerated, a greater amount of feed can be processed in a conventional reaction vessel.

Another embodiment of the invention is illustrated in Figure 2 which depicts a slightly modified burner vessel 50'. The reference numerals for similar components in Fig. 2 are also shown in Fig. 1, but the differences will be indicated by the main symbol ("'"). The same elements in FIGS. 1 and 2 will be denoted by the same reference numerals. The burner vessel 50' has a thermal regeneration catalyst for use in combination with the over-catalyst, regeneration catalyst and regeneration gas lower mixing riser to be transported down the extended recycle riser 82' and via the reactor conduit 48. 'The use of the catalyst to enter the lower mixed riser 120 meets. The catalyst and regenerative catalyst are contacted with at least a portion of a first stream of oxy-combustion gases from the lower conduit 64' at a lower portion of the lower mixing riser 120. The frustoconical base 63' of the combustor chamber 54' defines a cross-sectional area at the intersection "B" with the side wall 55' of the burner chamber 54' below the opening 68', wherein the catalyst is at the entry point "A" Enter the combustor chamber 54'. The cross-sectional area of the riser section 94' is smaller than the cross-sectional area of the combustor chamber 54' below the opening 68' to ensure increased pitch velocity through the riser section 94'. In addition, the lower mixing riser 120 has a smaller cross-sectional area than the cross-sectional area of the combustor chamber 54' below the opening 68' to promote uniform mixing of the catalyst particles with the gas stream. The lower mixed riser 120 also has a cross-sectional area that is smaller than the cross-sectional area of the riser section 94'. After mixing, the catalyst and gas mixture enters the turbulent zone 56' of the combustor chamber 54' via the opening 68' in the low distributor 66'. The flow rate of combustion gases from the low conduit 64' is insufficient to create a superficial velocity in the combustor chamber 54' that promotes rapid fluidization conditions. Thus, a turbulent flow bed 70' is provided in the turbulent zone 56' in the combustor chamber 54'. The additional combustion gases from the high conduit 72' are added by the high distributor 74' to produce rapid fluidizing flow conditions in the fast fluidization zone 58' as it polymerizes with the combustion gases from the low distributor 66'. The catalyst and combustion gases rise to the delivery zone 60' and exit into the separation chamber 100' through the separation device 96' to separate the catalyst that has fallen into the dense phase catalyst bed 78' from the rising used combustion gases. The used combustion gases rise to cyclone separators 98', 99' which separate the additional entrainment catalyst and exit via outlet conduit 110'. The fluidizing conduit 106' transfers a gas, possibly a combustion gas, to the dense phase catalyst bed 78' via the fluidizing distributor 108' to fluidize the catalyst in the dense phase catalyst bed 78'. One portion of the regenerative catalyst can be returned to the combustor chamber 54' via the extended recirculation riser 82' and the lower mixing riser 120 to heat the spent catalyst in the turbulent bed 70' and regenerate the remainder of the catalyst The reactor vessel 10 of Figure 1 is returned via a burner riser 12' to contact the fresh feed. All other aspects of the combustor vessel 50' having the lower mixing riser 120 are similar to the combustor vessel 50 of FIG. The operation of a hybrid riser is more fully described in U.S. Patent 4,340,566, which is incorporated herein by reference.

1 and 2 show a symmetrical configuration of the regeneration zone in which the separation chambers 100, 100' are located above the burner chambers 54, 54'. However, the turbulent zones 56, 56', the fast fluidization zones 58, 58' and the delivery zones 60, 60' may be contained in a separate burner vessel or in the vicinity of a vessel containing the separation chambers 100, 100'. . In this embodiment the catalyst is delivered from the burner vessel to a separator vessel by a conduit. Thus, the use of the present invention is not limited to a symmetric regenerator configuration, but may be a modified dense bed regenerator vessel.

10. . . Reactor vessel

12, 12'. . . Burner riser

14, 52. . . Spool valve

16. . . nozzle

18. . . Vertical tube

20. . . Feed nozzle

twenty two. . . Separation arm

24, 42. . . port

26. . . Separation container

28. . . Delivery catheter

30. . . Cyclone

32. . . Separator container

34. . . Collection chamber

36. . . Outlet nozzle

38. . . Immersion tube

43, 44. . . Baffle

40. . . Peeling section

46. . . Entrance

48, 48'. . . Reactor conduit

50, 50'. . . Burner container

54, 54'. . . Burner chamber

55, 55'. . . Side wall

56, 56'. . . Turbulent zone

58,58'. . . Rapid fluidization zone

60, 60'. . . Conveying area

61. . . Top oval cover

62, 86. . . Entrance chute

63, 63'. . . Base

64, 64'. . . Low duct

66, 66'. . . Low distributor

68, 76, 68'. . . Opening

70, 70'. . . Turbulent bed/turbulent catalytic bed

72, 72'. . . High catheter

74, 74'. . . High distributor

78, 78'. . . Dense phase catalyst bed

80. . . Upper chamber

82, 82'. . . Extended recirculation riser

84. . . Control valve

90. . . Transition

94, 94'. . . Erect pipe section

96, 96'. . . Separation device

97. . . Lateral arm

98, 99, 98', 99'. . . Cyclone separator

100, 100'. . . Separation chamber

102. . . Separation space

106, 106'. . . Fluidized catheter

108, 108'. . . Fluidized dispenser

110, 110'. . . Outlet conduit

112, 113. . . Immersion tube

120. . . Lower mixing riser

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a schematic elevational view of an FCC unit incorporating one of the present inventions.

Figure 2 is a schematic elevational view of an alternate embodiment of the present invention.

10. . . Reactor vessel

12. . . Burner riser

14, 52. . . Spool valve

16. . . nozzle

18. . . Vertical tube

20. . . Feed nozzle

twenty two. . . Separation arm

24, 42. . . port

26. . . Separation container

28. . . Delivery catheter

30. . . Cyclone

32. . . Separator container

34. . . Collection chamber

36. . . Outlet nozzle

38. . . Immersion tube

43, 44. . . Baffle

40. . . Peeling section

46. . . Entrance

48. . . Reactor conduit

50. . . Burner container

54. . . Burner chamber

55. . . Side wall

56. . . Turbulent zone

58. . . Rapid fluidization zone

60. . . Conveying area

61. . . Top oval cover

62, 86. . . Entrance chute

63. . . Base

64. . . Low duct

66. . . Low distributor

68, 76. . . Opening

70. . . Turbulent bed/turbulent catalytic bed

72. . . High catheter

74. . . High distributor

78. . . Dense phase catalyst bed

80. . . Upper chamber

82. . . Extended recirculation riser

84. . . Control valve

90. . . Transition

94. . . Erect pipe section

96. . . Separation device

97. . . Lateral arm

98, 99. . . Cyclone separator

100. . . Separation chamber

102. . . Separation space

106. . . Fluidized catheter

108. . . Fluidized dispenser

110. . . Outlet conduit

112, 113. . . Immersion tube

Claims (10)

A container (50) for burning a carbonaceous deposit from a catalyst, comprising: a lower chamber (54) having a base (63) and a side wall (55), the lower chamber including a first a combustion gas distributor (66) and a second combustion gas distributor (72); a catalyst inlet (62) between the first combustion gas distributor and the second combustion gas distributor, the substrate An intersection with one of the side walls (B) defines a first cross-sectional area; an upper chamber (100) in communication with the lower chamber, the upper chamber including a separator for separating the catalyst from the combustion gases (98, 99), a regenerative catalyst outlet (12) and a combustion gas outlet (110); and a vertical pipe section (94) extending upward from the lower chamber, the vertical riser having a smaller than the first cross section The second cross-sectional area of the area. The container of claim 1 further characterized in that the top of one of the risers includes a means (96) for initially separating the catalyst from the combustion gases. A container according to claim 1 or 2, further characterized in that a recirculation conduit (82) communicates with the upper chamber and the lower chamber. The container of claim 1 or 2, further characterized in that the catalyst and combustion gases are mixed together by the first combustion gas distributor (66') and dispensed into the lower chamber. A container according to claim 1 or 2, further characterized in that a gas distributor (108) is located in the upper chamber. A method for the combustion of carbonaceous deposits from a catalyst comprising: Introducing the used catalyst to a first chamber (54) via a used catalyst inlet (62); distributing the combustion gas to the underside of the used catalyst inlet at a rate that retains one of the catalyst beds a first chamber; distributing the combustion gas to the first chamber above the passage of the catalyst at a rate such that the combustion gas will be entrained when combined with the combustion gas distributed under the inlet of the catalyst a catalyst in the combustion gas, wherein more gas is distributed under the used catalyst inlet than above the inlet of the catalyst; and the catalyst in the combustion gas is lifted out of the first chamber An outlet (96) and entering a second chamber (100); separating the catalyst from the combustion gas; collecting a catalyst in a bed (78) in the second chamber; from the second chamber Removing the catalyst; and recovering combustion gases from the second chamber. The method of claim 6, further characterized by: distributing the combustion gas to the first chamber below the inlet of the catalyst to provide a superficial velocity of less than 1.1 m/s; and distributing the combustion gas The first chamber above the use of the catalyst inlet provides a superficial velocity of at least 1.1 m/s when combined with the combustion gases distributed below the inlet through the catalyst. The method of claim 6 or 7, further characterized in that the catalyst is recirculated from the second chamber to the first chamber. The method of claim 6 or 7, further characterized by: The catalyst and the combustion gases exit the first chamber via a riser tube (94). The method of claim 6 or 7, further characterized in that the catalyst is accumulated in one of the second beds (78) of the second chamber.