GB2027608A – Gas distribution apparatus for use with fluidized beds
– Google Patents
GB2027608A – Gas distribution apparatus for use with fluidized beds
– Google Patents
Gas distribution apparatus for use with fluidized beds
Download PDF
Info
Publication number
GB2027608A
GB2027608A
GB7923525A
GB7923525A
GB2027608A
GB 2027608 A
GB2027608 A
GB 2027608A
GB 7923525 A
GB7923525 A
GB 7923525A
GB 7923525 A
GB7923525 A
GB 7923525A
GB 2027608 A
GB2027608 A
GB 2027608A
Authority
GB
United Kingdom
Prior art keywords
bed
gas
fiuidized
distribution members
members
Prior art date
1978-07-06
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
GB7923525A
Other versions
GB2027608B
(en
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Honeywell UOP LLC
Original Assignee
UOP LLC
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
1978-07-06
Filing date
1979-07-05
Publication date
1980-02-27
1979-07-05
Application filed by UOP LLC
filed
Critical
UOP LLC
1980-02-27
Publication of GB2027608A
publication
Critical
patent/GB2027608A/en
1983-02-02
Application granted
granted
Critical
1983-02-02
Publication of GB2027608B
publication
Critical
patent/GB2027608B/en
Status
Expired
legal-status
Critical
Current
Links
Espacenet
Global Dossier
Discuss
Classifications
B—PERFORMING OPERATIONS; TRANSPORTING
B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
B01J8/00—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes
B01J8/18—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes with fluidised particles
B01J8/1818—Feeding of the fluidising gas
Description
1
GB 2 027 608 A 1
SPECIFICATION
Gas distribution apparatus for use with fiuidized beds
This invention relates to fiuidized beds and 5 particularly to apparatus for distributing a fluidizing gas to the bed. A typical fiuidized bed, such as that utilized in a fiuidized catalytic cracking unit, contains a large quantity of relatively expensive catalyst particles which might 10 range in size from 20 to 150 /u (microns). In order to minimize the quantity and cost of catalyst required to achieve a given result in a process operation, the gas which is directed upwardly through the bed should contact ail of the catalyst 15 uniformly and should remain in contact with the catalyst for a maximum length of time. A catalyst unit can be very large, such as 10 meters in diameter. One common way of achieving gas distribution in such a unit is to locate a perforated 20 plate under the fiuidized bed or a planar assembly of pipes in the bottom of the unit which have many branches and perforations therein through which the fluidizing gas is carried to the bed. Pipe type units are expensive while either type of unit is 25 somewhat inefficient, since the gas flow tends to channel upwardly through portions of the bed immediately above the perforations while bypassing other portions. Also, when the blower(s) which force the fluidizing gas through the bed is 30 (are) shut down, the bed slumps and many of the particles forming it tend to get sucked into the perforations by the back surge of gas which occurs at shutdown. The particles can damage the blower(s) and can also present problems when the 35 blower(s) is (are) restarted due to pressure required to force the particles back through the perforations. In addition, and of greater concern, the particles are usually very erosive and their contact with the perforations as they pass through 40 them can quickly enlarge the openings. The enlargement will vary the pressure drop of the system and change the flow characteristics so as to affect the efficiency of contact of the catalyst and fluidizing gas, since it is important that a given 45 pressure drop be maintained through the bed.
One type of flow distributor which is in use and which is intended to reduce backflow of catalyst, has a threaded hollow base portion which is integral with an upper radially perforated portion 50 having very large perforations (about 4.76 mm). The upper portion is covered by a conically topped cylinder which causes the gas exiting the perforations to be directed downwardly toward the base in an annular configuration. The 55 downward flow helps to ensure maximum contact time with the catalyst since the flow reverses direction at the bottom of the bed and then moves upwardly through the entire bed. However, the aforementioned flow distributors are very 60 expensive. Also, the initial downward flow of gas tends to blow the erosive catalyst particles against whatever is under the distributors and quickly erodes it. The damage can be reduced by placing large washers under the distributors which can be
65 periodically replaced as they become worn.
The present invention seeks to provide a gas distribution apparatus for a fiuidized bed which will provide uniform gas flow distribution and maximum contact time between the gas and the 70 particles making up the bed.
According to the present invention apparatus for uniformly distributing a gas to a fiuidized bed having a particle size in the range 20 to 150 ft comprises gas supply manifold means mounted at 75 the bottom of said bed, said manifold means having a plurality of flow distribution members projecting generally vertically upwardly therefrom, each of said flow distribution members having a closed top portion and being of a generally tubular 80 configuration, the walls of each said member being defined over a major portion of its length by a continuous helically disposed length of wire having a relatively flat outer surface which is outermost in the member and tapering side 85 surfaces which converge towards the axis of the helix and are jointed at their inner ends by an inner surface which is fixed at spaced points along its length to a plurality of inner longitudinal support members, adjacent turns of said outer surface 90 defining a continuous helical slot having a width less than the diameter of the majority of the particles in the bed, said helical slots serving to distribute fluidizing gas from said manifold means horizontally through a fiuidized bed in which said 95 flow distribution members are mounted while preventing substantially all inward movement of the particles forming the bed through said slots when the outward flow of gas through said slots is terminated so as to produce a negative pressure 100 within said distribution membecs.
The manifold means is preferably a large plate or series of plates with uniformly spaced threaded perforations into each of which a flow distribution member is screwed. The manifold means can also 105 be made of pipes or tubes attached to each other in a planar array with upward facing threaded openings for the flow distribution members. A slot width of 20 to 50^ is quite satisfactory when the sizes of the particles of the fiuidized bed are in the 110 range of 20 to 150 fi. Generally the slot width will be less than about 75 /u. The slotted portion of the flow distributor member is preferably formed in the manner taught in U.S. Patent 2,046,458. A slot width of less than 20 /x would, of course, 115 ensure that no particles in the range of 20 to 1 50 H could pass through the slot openings, but such small openings could produce an excessive pressure drop. In one typical fiuidized bed unit, a pressure drop through the slot openings of 0.8 psi 120 (0.056 kg/cm2) is desired when gas at 20 to 40 psi (1.40 to 2.80 kg/cm2) is present in the manifold means. The number and spacing of the distributor units is preferably selected to achieve this desired pressure drop. Obviously, if the 125 pressure drop through each unit is large, then only a few units can be used to achieve the desired overall pressure drop. Although spacing between units can vary between about 15 to 78 cm, the greater spacing provides less uniform flow
2
GB 2 027 608 A 2
distribution in the bed. Conversely, too little pressure drop through an individual unit would necessitate that a large number of units be used. This would make for very uniform flow distribution .
5 in the bed but would be costly in terms of the extra flow distribution members and manifold openings required.
The invention will now be described, by way of example, with reference to the accompanying 10 drawing, in which:—
Figure 1 is a perspective, partially broken away, view of a fiuidized bed containing a catalyst regenerator vessel in which a gas distribution apparatus in accordance with the invention is 15 mounted,
Figure 2 is a side view on an enlarged scale, partly in section, of one of the improved flow distribution members, and
Figure 3 is a section view on a further enlarged 20 scale taken on the line 3—3 of Figure 2.
Referring to Figure 1, a regenerator vessel 10 is shown containing a fiuidized catalyst bed 12. The unit is shown as corresponding in function to the catalyst regeneration unit of U.S. Patent 25 3,953,175, the disclosure of which is incorporated by reference herein. Spent catalyst is delivered to the vessel 10 through an inlet pipe 14 while pressurized air is forced by a blower 18 through a check valve 20 and a pipe 22 into a manifold 24 30 defined by the bottom end of the vessel 10 and by bottom bed plates 26 which are supported in the vessel 10 on beams 28. Mounted at spaced intervals on the bed plates 26 are a plurality of identical hollow flow distribution members 35 indicated generally at 30 each of which have threaded base portions 32 retained to the base plates 26 by nuts 34. Each distribution member 30 is closed at its upper end by an end plate 36 which prevents catalyst from the bed 12 from 40 entering the member 30 when the blower 18 is shut down so as to cause the catalyst bed to slump. The members 30 include a helical slot 38 defined by the gap between wraps of a shaped helically wrapped wire 40 which is welded at a 45 plurality of spaced points to a plurality of internal rod members 42 (one of which is shown in Figure 3). The helical wrap wire 40 is preferably made of a material such as stainless steel which is resistant to corrosion and erosion from the 50 catalyst particles of the bed 12. The width of the slot 38 should be as constant as possible and generally less than about 75 /x. For use with a catalyst bed 12 having particles sized from 20—150 (i the width of the slot 38 preferably is 55 from 20—50 /u.
Claims (8)
1. Apparatus for uniformly distributing a gas to a fiuidized bed having a particle size in the range of 20 to 150 [i comprising gas supply manifold means mounted at the bottom of said bed, said manifold means having a plurality of flow distribution members projecting generally vertically upwardly therefrom, each of said flow distribution members having a closed top portion and being of a generally tubular configuration, the walls of each said member being defined over a major portion of its length by a continuous helically disposed length of wire having a relatively flat outer surface which is outermost in the member and tapering side surfaces which converge towards the axis of the helix and are joined at their inner ends by an inner surface which is fixed at spaced points along its length to a plurality of inner longitudinal support members, adjacent turns of said outer surface defining a continuous helical slot having a width less than the diameter of the majority of the particles in the bed, said helical slots serving to distribute fluidizing gas from said manifold means horizontally through a fiuidized bed in which said flow distribution members are mounted while preventing substantially all inward movement of the particles forming the bed through said slots when the outward flow of gas through said slots is terminated so as to produce a negative pressure within said distribution members.
2. The apparatus of claim 1, wherein the distribution members are threadedly engaged with the manifold means.
3. The apparatus of claim 1 or claim 2, wherein the radially inner surface of the helically disposed wire is rounded and is welded to longitudinal rods forming the support members.
4. The apparatus of any preceding claim, wherein the helical slot width is less than 75 fx.
5. The apparatus of claim 4 wherein the helical slot width is in the range of 20 to 50 fx.
6. Gas distribution apparatus for a fiuidized bed incorporating a plurality of flow distribution members substantially as hereinbefore described with reference to, and as illustrated in. Figures 2 and 3 of the accompanying drawing.
7. A fiuidized catalyst bed unit incorporating a gas distribution apparatus as claimed in any preceding claim.
8. A fiuidized catalyst bed unit substantially as hereinbefore described with reference to, and as illustrated in, Figure 1 of the accompanying drawing.
60
65
70
75
80
85
90
95
100
105
110
Printed for Her Majesty’s Stationery Office by the Courier Press, Leamington Spa, 1980. Published by the Patent Office, 25 Southampton Buildings, London, WC2A 1 AY, from which copies may be obtained.
GB7923525A
1978-07-06
1979-07-05
Gas distribution apparatus for use with fluidized beds
Expired
GB2027608B
(en)
Applications Claiming Priority (1)
Application Number
Priority Date
Filing Date
Title
US05/922,461
US4170626A
(en)
1978-07-06
1978-07-06
Gas distribution apparatus for use with fluidized beds
Publications (2)
Publication Number
Publication Date
GB2027608A
true
GB2027608A
(en)
1980-02-27
GB2027608B
GB2027608B
(en)
1983-02-02
Family
ID=25447083
Family Applications (1)
Application Number
Title
Priority Date
Filing Date
GB7923525A
Expired
GB2027608B
(en)
1978-07-06
1979-07-05
Gas distribution apparatus for use with fluidized beds
Country Status (10)
Country
Link
US
(1)
US4170626A
(en)
JP
(1)
JPS5513199A
(en)
AU
(1)
AU523790B2
(en)
BE
(1)
BE877552A
(en)
CA
(1)
CA1110832A
(en)
DE
(1)
DE2927111C3
(en)
ES
(1)
ES482238A1
(en)
FR
(1)
FR2430257A1
(en)
GB
(1)
GB2027608B
(en)
IT
(1)
IT1122054B
(en)
Cited By (2)
* Cited by examiner, † Cited by third party
Publication number
Priority date
Publication date
Assignee
Title
EP0417153B1
(en)
*
1988-05-26
1993-05-05
A.Ahlstrom Corporation
Distributor plate for fluidized bed reactor
GB2329597A
(en)
*
1995-02-15
1999-03-31
Air Liquide
Arrangement of a retaining grille of an active material in a vessel, and a vessel so equipped
Families Citing this family (5)
* Cited by examiner, † Cited by third party
Publication number
Priority date
Publication date
Assignee
Title
US4328177A
(en)
*
1980-08-29
1982-05-04
Procon International Inc.
Vapor-liquid contacting apparatus
JPS6079540U
(en)
*
1983-11-08
1985-06-03
三井造船株式会社
Gas distribution plate support device for gas phase fluidized bed reactor
JPH01203016A
(en)
*
1988-02-08
1989-08-15
Arai Tekkosho:Kk
Small fluid treating element
US5584996A
(en)
*
1992-05-19
1996-12-17
Envirex Inc.
Apparatus and method for distributing liquid containing evolvable glass into a fluidized bed of a reactor
CA2144028A1
(en)
*
1994-04-29
1995-10-30
Eugene Mazewski
Backflow prevention system for media bed reactor
Family Cites Families (5)
* Cited by examiner, † Cited by third party
Publication number
Priority date
Publication date
Assignee
Title
CA544786A
(en)
*
1957-08-13
S. Dalton Benjamin
Contacting solids with gases
US2049206A
(en)
*
1929-04-01
1936-07-28
Edward E Johnson Inc
Method of forming well screens
US2046456A
(en)
*
1933-09-11
1936-07-07
Edward E Johnson Inc
Well point and process of making the same
US2046458A
(en)
*
1934-11-10
1936-07-07
Edward E Johnson Inc
Screen
DE2610973A1
(en)
*
1976-03-16
1977-09-29
Uhde Gmbh Friedrich
REACTION FURNACE WITH FLUID BED
1978
1978-07-06
US
US05/922,461
patent/US4170626A/en
not_active
Expired – Lifetime
1979
1979-07-04
AU
AU48653/79A
patent/AU523790B2/en
not_active
Ceased
1979-07-04
FR
FR7917353A
patent/FR2430257A1/en
active
Granted
1979-07-05
GB
GB7923525A
patent/GB2027608B/en
not_active
Expired
1979-07-05
ES
ES482238A
patent/ES482238A1/en
not_active
Expired
1979-07-05
DE
DE2927111A
patent/DE2927111C3/en
not_active
Expired
1979-07-06
IT
IT24169/79A
patent/IT1122054B/en
active
1979-07-06
BE
BE0/196190A
patent/BE877552A/en
not_active
IP Right Cessation
1979-07-06
JP
JP8579879A
patent/JPS5513199A/en
active
Granted
1979-07-06
CA
CA331,255A
patent/CA1110832A/en
not_active
Expired
Cited By (3)
* Cited by examiner, † Cited by third party
Publication number
Priority date
Publication date
Assignee
Title
EP0417153B1
(en)
*
1988-05-26
1993-05-05
A.Ahlstrom Corporation
Distributor plate for fluidized bed reactor
GB2329597A
(en)
*
1995-02-15
1999-03-31
Air Liquide
Arrangement of a retaining grille of an active material in a vessel, and a vessel so equipped
GB2329597B
(en)
*
1995-02-15
1999-08-11
Air Liquide
Arrangement of a retaining grille of an active material in a vessel,and a vessel so equipped
Also Published As
Publication number
Publication date
JPS5746369B2
(en)
1982-10-02
BE877552A
(en)
1979-11-05
CA1110832A
(en)
1981-10-20
US4170626A
(en)
1979-10-09
DE2927111A1
(en)
1980-01-17
ES482238A1
(en)
1980-02-16
FR2430257B1
(en)
1983-06-17
IT7924169D0
(en)
1979-07-06
IT1122054B
(en)
1986-04-23
AU523790B2
(en)
1982-08-12
FR2430257A1
(en)
1980-02-01
DE2927111B2
(en)
1980-10-23
JPS5513199A
(en)
1980-01-30
DE2927111C3
(en)
1981-09-10
GB2027608B
(en)
1983-02-02
AU4865379A
(en)
1980-01-10
Similar Documents
Publication
Publication Date
Title
US3685971A
(en)
1972-08-22
Flow distributing apparatus
EP0518579B1
(en)
1995-09-20
Automatically adjustable fluid distributor
GB2027608A
(en)
1980-02-27
Gas distribution apparatus for use with fluidized beds
US9636654B2
(en)
2017-05-02
Modifying flow of a reactor inlet distributor
KR102356416B1
(en)
2022-01-26
Multi-tube radial bed reactor
KR950004328B1
(en)
1995-04-28
Catalyst system for distillation reactor
GB2077121A
(en)
1981-12-16
Device for distributing a liquid in thinfilm form in vertical heat-exchangers
US7459132B2
(en)
2008-12-02
Apparatus for dehydrogenation of ethylbenzene to styrene and method of retrofitting the apparatus
US5635140A
(en)
1997-06-03
Self-aerating spent catalyst distributor
GB2074698A
(en)
1981-11-04
Water seal drum
EP0656228B1
(en)
1999-01-27
Method and apparatus for uniform loading of catalyst tubes
US20050011972A1
(en)
2005-01-20
Device for homogeneous distribution of a fluid in a chamber and uses thereof
US3972567A
(en)
1976-08-03
Apparatus for and method of distributing particles over a zone
CN111182961A
(en)
2020-05-19
System and method for improving flow in a radial flow reactor
US4114324A
(en)
1978-09-19
Silo for bulk materials with fluidizing means
EP0085610A2
(en)
1983-08-10
Gas distributor for fluidized beds
CN112512678A
(en)
2021-03-16
Device for distributing a fluid that can be arranged in a reactor comprising a fixed catalyst bed
US2979315A
(en)
1961-04-11
Hold-down plates
AU6466098A
(en)
1998-10-12
Tower packing support plate
EP0931585A1
(en)
1999-07-28
Radially corrugated catalyst unit
GB2195323A
(en)
1988-04-07
Arrangement for controlling flow of granular material through a passage
EP0061885B1
(en)
1985-07-03
Apparatus and method for transferring solids
US2548285A
(en)
1951-04-10
Method and apparatus for hydrocarbon conversion
JP2730283B2
(en)
1998-03-25
Reforming tube and reformer
CN109045947B
(en)
2021-08-17
Fluidized bed cluster reactor
Legal Events
Date
Code
Title
Description
1985-02-27
PCNP
Patent ceased through non-payment of renewal fee
