OCL' 20, 1953
,
_
E. v. BERGSTROM ETAL
2,656,306
METHOD AND APPARATUS FOR CONDUCTING MOVING CONTACT
Filed May 25. 1951
MATERIAL HYDROCARBON CONVERSION PROCESSES
~
2 Sheets-Sheet l
Oct. 20, 1953
2,656,306'
E. v. BERGSTROM ETAL
METHOD AND APPARATUS FOR CONDUCTING MOVING CONTACT
MATERIAL HYDROCARBON CONVERSION PROCESSES
Filed May 25
.
2 Sheets-Sheet 2
1951
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INVENTOR.
En? /Í/ßzrsífam
BY E YZ È?
2,656,306
Patented ocr. 2o, 1953
UNITED STATES PATENT ori-"rc1:
METHOD AND APPARATUS FOR CONDUCT
ING MOVING CONTACTV MATERIAL `HY
DROCARBON CONVERSION PROCESSES
Eric
Sorf, Bergstrom,
Fanyvood, N,
,ShortrÍlillsg
J., assignors4
and toEdward
_Socony
Vacuum Oil Company, Incorporated, a corpo
ration of NëW York
Application Mayet, 1951, serial No. 228,293
Y
l
1'5 Claims.
,
(c1. 19e-s2)
.
.
2
.
.
carbons which Ado boil inthe gasoline' boiling
1 This invention pertains to processes for the
conversion of fluidy hydrocarbons in the presence
range. , Incident to the cracking operation, a de
of a granular contact material which may or may
posit of carbonaceous material orv coke is deposit
ed on _the surface ofthe catalyst, impairing its
not be>v catalytic inI nature. Typical processes to
which this invention pertains are the catalytic
ability tov function catalytically. The coked or
. spent catalyst is removed from the bottom of the
cracking conversion', isomerízation, hydrogena
tion, reforming,V dehydrogenation, aromatization,
reaction zone continuously and transferred to
thel top of a' gravitating compact column of> par
hydroforming, treating and desulfurization of pe
ticles in a regeneration zone._ The catalyst gravi
trcleumY fractions.v Also typical are the colring,
vviscosity reducing of petroleum residuums and l0 tating through the regeneration zone is contacted
With a combustion supporting gas, such as air,
high temperature pyrolytic conversion processes
to burn off thevcoke deposits from the surface of
such as the conversionof propane and- ethane to
ethylene or of methane to acetylene. In these
the catalyst. The coke-‘4free or regenerated cat
alyst is withdrawn continuously from the bottom
latter processes the granular contact material
serves merely `as a heat carrying material.
An‘important commercial unit for continuous
ly conducting‘reactions of this type is one where
in the- granular contact material is passed cy
clicall-ïy through` hydrocarbon conversion andl con
tact material reconditioning zones inA which it
flowsv downwardlyv as a1 substantially' compact
column. The contact material employed in such`
a process: may'befa-v catalyst in the form of natural
and-treated‘clay ,~ b'a'uXites, inert‘carriers impreg
nated with certain-catalyst active metallic or;-ides` or synthetic associations of_ silica, alumina',
' ofthe column in the regeneration zone and trans
ferred to> the top of the reaction Zone,v complet
ing the continuous path. This process involves
the use of high temperatures and may involve the
use of high pressures. For' example, the reaction
' zone may be maintained’at about vsoo-1100o F.,
suitable cracking temperature, and the regen
eration z'one mayv be maintained at about 1000
1300°VF., suitable regeneration temperature. The
catalyst islifted, therefore, at temperatures of
approximately 8004-1200" F., or 'thereaboutsr
.
AsY the catalyst _material gravitates through
the“ contacting zones', the gas or vapors contact
the catalyst surface" by passing through the voids
between the' particles. It is desirable to main
tain the lflow of gas" through the bed uniform for
magnesiav or- of' combinations thereof` to which
may be addedìsmalladditional amounts of-metal
lic oxides for specific purposes. When the con
tact material is "employed for heatcarry'i'ng pur'
poses only" it- maytak'e'the form of metal balls,
SO a variety of reasons: ` For example, channelling
terial'may consistof a low activityäclay catalyst,
unifor'ìm conversion of the hydrocarbon charge.
that‘which'isf obtained when the' gas' flows uni
of gas throughthe reactor may'result in non-uni'
form coke"v deposition _on thecatalyst and >rion
capsules containing'fusible‘alloys, pebbles, carbo
rundum, mullite, zirconium oxide, fused alumina
and thelike: Forßcokiii‘g" processes the solid maf-f
The- cracking eiiiciency is materially reduced from
petroleumv coke orf porous» inert material such'
the term “granular” is employed broadly#herein`
formly*through‘thcsbïed.` Qhannelling in theY re
gr‘zner‘ator> causes the particles passing through
the" channel to overheat .andA thereby damage the>
catalytic activity' of,A these"I particles. Those par
3-100 meshTylerScreen Analysis, and preferably:
gain their _former 'cracking'activity
aspuniice’.` The coñtàîctfmaterial may' bein- the
«form of“ pellètshsphere's, tablets:- or" irregular
shapedpartic'les and 'it should be understood that
asscoveringfgany of'îthe above». The contact `ma’ 40 ticles'not receivin'g‘their'shareof combustion sup
porting'A gasl ar‘e‘notì s'uiñci'e'ntly regenerated to 're
terial. particles» may range -in size from»v about
Channelling is "caus
y 4
i
ri' these movingbed sys
n >or ' accumulation of'fine '
be.Foripurposes
describedÍWith
of~ reference
illustration,
to the
a specific
invention
process',_» 45
a‘catalytic crackingproce'ss» I?i the riiovinfg"bed’h
system.>
granularof.Vform
catalytic
are contacted
cracking,with
the suitablyfpre
particles"`
’.„alystï' particles when they Ci-rnpinge upon each
pared hydrocarbons While‘gravitating downward 50` 'other or themetal walls ofthe enclosed system,
ly ‘through> a- reaction zone in »the form of a sub
Attrition _is yalsoßceused by the particles >sliding
stantially compact column. The feed stock,
againstweachrlother (or >against the metal walls.
usuallyfagas oil boiling-somewhat above the gaso
line boiling-mange,- cracks` inthe-»presence of the
catalyst, forming substantial amounts of hydro
Theñnes tend `to classify or gather together, es
».¿Defííáï’ly When the @altalyst is passed through slop
55
ing chutes’. In addition to causing the gas to
3
2,656,306
¿i
vchannel through the beds, the fines 'cause an
increased pressure drop across the beds. For
these and other reasons, it is necessary to re
ïmove fines from the system and replenish the in
the high pressure vessel. For example, if it is
desired to operate the lift tank at 5 p. s. i.
(gauge), the height of the compact leg must be,
for a catalyst having a poured density of 45
pounds per cubic foot, at least:
ventory with fresh catalyst.
Recently, moving bed conversion systems have
been developed which incorporate gas lifts to
144
raise the contact material from the bottom of \
one gravitating column to the top of the other
column. When a side by Aside 'arrangement of 10
regenerator and reactor is used, two gas lifts are
required. When a superimposed arrangement
is utilized, such as reactor over regenerator or vice
versa, only one gas lift need be used. A pre
ferred form of lift comprises essentially a sub
stantially vertical lift pipe, a lift tank located
at the bottom of the pipe and a separator located
at the top of the pipe, the ends of the pipe be
ing projected to an intermediate location in each
vessel. The catalyst is introduced into the feed tank to form a substantially compact mass about
the bottom of the lift pipe. The major portion
of the lift gas is introduced through a primary
gas conduit located a short distance below the
pipe and directed up the pipe. A relatively
smaller amount of secondary gas is introduced
into the lift tank to enter the bed'of catalyst
a spaced distance away from the lower end of the
lift pipe. , The primary gas passes up the pipe
without passing through any substantial thick- '»
ness of catalyst bed whereas the secondary gas
passes through at least a portion of the bed to
push catalyst into the primary gas stream. The
particles, both granular and fines, are suspended
by the gas and lifted up the pipe to the separa
tor. rThe particles settle from the gas in the
separator onto a bed of the solid material about
the top of the lift pipe, and the gas is withdrawn
separately from the vessel.
p.s.i.
0r
height= 16 ft.
For satisfactory operation, it is found desira
ble to provide a substantially compact column
which is 15-50 per- cent longer than the calculated
length. For example, for the assumed pressure
of p. s. i. in the lift tank, a leg of about 18-24
ft. long would be satisfactory. It is assumed
hereinabove, however, that the leg of compacted
catalyst is substantially vertical. Where the leg
is not vertical, longer legs must be used to pro
Vide satisfactory results. The above applies to
gravity feed legs which are tapered so as to over
come the effect of the gas expansion as it passes
upwardly through the leg. For legs of uniform
cross-section along their lengths, somewhat
greater lengths than those indicated should be
employed.
The elutriator is operated by releasing cata
lyst into the top of the vessel in the form of a
shower and gas into the bottom of the vessel
to pass upwardly through the falling catalyst.
The upward velocity of the gas is controlled to
effect lifting and entrainment of the fines.A The
gas and fines are withdrawn from the top of the
vessel and the fines-free material is withdrawn
from the bottom. It is necessary that the seal
column between the lift tank and the elutriator
The lift tank is generally operated- at a pres 40 be prevented from rising into the elutriator.
Hence, the level of the seal column has to be
sure above atmospheric and the separator at or
maintained fixed at a level beneath the elutria
even below atmospheric. At least there must be
tor.
a pressure drop across the lift pipe to effect
It is an object of this invention to provide ap
transfer of the contact material therethrough.
paratus and method for continuously introduc
A suitable lift tank is disclosediin more detail in
ing contact material into a high pressure region
copending application for Letters Patent Serial
at a substantially constant rate from two low
Number 211,253, filed February 16, 1,951. A suit
pressure regions, and preferentially supplying
able lift pipe is disclosed and claimed in copend
the contact material from one of the low pres
ing application Serial Number 210,942,` filed Feb
ruary 14, 1951, and a suitable separator is dis 50 sure regions to the high pressure region rather
closed and claimed in copending application _Se
than from the other low pressure region.
rial Number 211,238, filed February 16, 1951.
It is a further object of this invention to pro
ït has been proposed that a side stream of cons
vide method and apparatus for combining two
tact material be withdrawn from the bottom of
streams of contact material to form a column of
the separator and gravitated through an elutria 55 contact material of substantially constant.
tor. In this scheme the fines would be removed
height adapted to feed continuously into a high
in the gas passed through the elutriatory and the
pressure region at a substantially constant rate
fines-free, granular contact material gravitated
of flow and effecting a preferential ilow of the
into the top of the lift tank. Because the lift
contact
material from one of the streams to the
tank is operated at a_ higher pressure than the 60
high pressure region.
f
elutriator, a substantially compact column of
These and other objects of the invention will
granular material of sumcient length must be
be made more apparent in the following descripmaintained between the elutriator and the tank
tion of the method and apparatus referred to
to provide a seal between the vessels and. effect
smooth feeding of the contact material into the 65 in the attached drawings. The sketches are all
tank. For example, the minimum required length
of this leg may be conveniently calculated by
dividing the weight of catalyst in the leg by the
highly diagrammatic in form, included only to
average cross-sectional area, in pounds per square
bed cracking system incorporating the instant
illustrate the form and nature of the invention.
Figure 1 is a vertical elevation of a moving
inch, which is greater than the pressure difier 70 invention.
ential between the top and bottom of the leg by
Figure 2 is a vertical elevation in section show
a safe margin. If this leg is not maintained, the
ing the details of the combining boxes of Fig
upward flow of gas through the leg will have sum
ure 1. .
cient velocity to disrupt the column and inter
Figure 3 is a plan view of the upper combin
rupt or prevent the catalyst from feeding into 'I5 ing box as seen on plane 3*-3 of Figure 2.
6?
Figure» 4f is “a plan View of the lower combin
ing- box»y as. seen on plane lli-4; `of»Figi-lirez.
Figure 5 is a Vertical sectional»V view. of the liïit
tank of Figure 1.
Referring now to Figure 1>, the Vmain stream of OX
catalystis withdrawn continuously-from the bot
the 'separator lc and the 'gas is discharged
throughv the» conduit 29'. 'I-'he lift- tank 'ifs usual‘ly'
operated at 'an advanced vpres-sure and» the sepe
arato'r is 'generally- operated atl atmosphericprese'
sure, or in some instances, slightly less.
At least one »side stream of catalyst- is with#
tom of- theseparator l10- th-rc'ugh the conduit H.
drawn from the bottom foi theyessel HT through
The ‘catalyst 'g_;r-xa.vitates‘i downwardly-.as a sub
stantially compact column 'into the top of the
conduits K55. Preferably a multiplicity of with;-
An inert ‘gas is introduced into the top ot the
vessel i2 or the bottom ofthe ffeed» leg ll- to- pre
vent the transf-er of reactant gas >through the
drawar conduits
used vattached atv locations
equally distributed about the bottom» "ofA the vessel. These downwardly directed conduits» are
combined into a ¿single conduit '3b. Gonduits ’3l-f
32 are attached to the lower end of conduit` '3'0-r
to split 'the catalyst' stream intol two separate
streams. The íirst `stream ‘is- gra'vita'ted- down
pipe It. The» catalyst gravitates through the-re
wardly as a substantially compact column from
actor as »a substantially compact bed and» is- con
the separator-to» an upper ‘combi-ning box, located
tacted therein with reactant hydrocarbons, ‘suit
ably prepared for reaction», introduced 'through
stream' is in substantially» compact -i'orm down
reaction vessel i12, which may loe-maintained at
an advanced: pressure ‘or about 5-31)` p. s. i.
(gauge) and aV temperatureof‘abcut SOO-1100" F.
at the bottom of theV conduit 132i.' The second
to- a release valve 351 in- the conduit 32. The flow
of this stream isl controlled! by the valve 35 so as
to form a- shower of descending particles below
the valve. Of course, the two streams can» be
the >conduit I3; Thereactants may be in liquid,
VaporY or mixed liquid and vapor form, preheated,
generally, to about 700-800F‘F., 'although higher
or lower temperature may, in -certain instances,
be used, depending, to some extent, upon the
type of charging stoclr.` The hydrocarbons are
converted, upon` contacting the catalyst, to more
desirable materials and the productsfare-removed
from the vessel through the conduit lli to frac
tionation and processing apparatus, not shown.
Inert 'gas is introduced 'in-to the bottom of the
vessel through the conduit 2i» 'to prevent kthe
downward movement of reaction gases.
The
spent catalyst is withdrawn continuously from
the bottom of the Vessel and introduced into the
depressurizer I5, usually,` where the pressure is -
carried in separate conduits from the separator;
if desired, instead of the arrangement shown.
An elutriator vis attached tothe bottom of'A the
conduit 32:». The- parti‘cl'es! pass downwardly
through the vessela Gas, introduced through the
conduit 22, passesy upwardly» through the par
ticles. rlîhe gas flow is controlled, by means- of»
the valve 55, to eiiect suspension- ofthe fine-'par
ticles in the gas stream, without «interferi-ng; with
the downward movement vO‘f-'the granules. The
:ânes-free contact material is removed ‘from they
vessel throughthe conduit 31'A to the-'upper com
reduced practically to atmospheric. Thisis done,
bining box.
primarily, because it is simpler and» more eco
nomical to regenerate or restore the material at
vessel entrained-in thegas;
Referring» now totheFigu're 2ï, the conduit-fit
terminates within the upper combining boxv 33»
substantially atmospheric pressure. In some
cases, however, the contact' material is regen
erated at advanced pressure. This pressure may
be greater than» that in the reactor, and in such
a case, it may be found morev expedient to pla-ce
the kiln over the reactor.
The depressurized catalyst is-gravitated down
The ñ'nes pass out the» »top of the
The conduit 31 alsoterminate's in the top-ofthe
upper combining box. A» withdrawal conduit /38
is-attached to the bottom of» thebox». The 'with
drawal' aperture o’f¿ the conduit 38 inthe bottom
of the box «331 is locatedâ substantially directly
45 below the discharge aperture ofthe conduit 3T.
ditioner or kiln llin wherein` it is contacted with
carrying the second stream. f_I‘his is thepre
ferred form of the invention, however,inv less
combustion supporting gas and> the` coke, de
posited’on the surface of the particles- during
preferred form- the second-î stream can be- dis
charged at» any location above the bed' in- the
wardly 'as' a compact column through the'recon
reaction, is burned.; The kiln> is maintained at 50 combining» zone. The dispersedJ particles, after
contacting the surface of'v the`~bed,_roll down the'
a temperature of about» 100G-130W’ F. Tempera-`
inclined surface to a- location» above» the with'
tures higher than that heat damage the cata
a heat carrying medium is required, however,
drawal aperture.` T-he v1discharge‘aperture of' the
conduit r¿l carryingfthe Vñïrst' stream is laterally
through the conduit 25-A into the top Ortheiift
that preferably vthe anglel with» thehorîzontalf of 1
lyst, 'impairing its catalytic activity.> Where only
inert refractory particles',` such as‘- corhart, or 55 displaced VVfrom the withdraw-alfV aperture, so' ‘that’
an imaginary line- connecting the closest point
mullite, may be used and restored at tempera
of the dischargeaperture- with'lthatf-of' the with
tures well in excess of the above-without dam
drawal aperture isflocat’ed- ator about'the iii--V
age. In order to control,theftemperatureof the
ternal angleof catalyst-flow. Theang'le ofl'in
kiln, cooling coils may be utilized. A-ir is intro
duced into the kiln through- the conduit I1 and 60 ternal flow` varies from about~r 65f» to 8D" degrees
depending upon» the 'nature rof the catalyst;
flue gas is removed fromA the- iilmV through the
When catalyst,is-{withdrawn--from an outlet lo@
conduit I3; A stream of flue gasY istaken from
cated` beneath a» bedl ofJthematerial; the with->
the kiln through the conduit 22 to~supply the
drawal occurs from » aff generally 'cone-shaped ree»
elutriator, disclosedin mcredetail hereinafter.
gion locatedA directly >above the' îwithdrawalf 'ap’er`-`>
The catalystr is withdrawn fromthe bottom `of
ture: The slope-cfïthe'side'felement of the cone
the 'kiln> i6> through the conduit23'tol a depres
variesi rom -65-ßordegrees> broadly depending; upf-f
surize'r 24. The catalyst is then gravitated down
on thecatalyst. In »mosti-cases it liasfb'een vfound
wardly as a substantially compact column
ì tank 26.
A` suitable inert lift- gas, such as flue 70 a line» through thenearestf points- on: adjacent
gas, air or steam, which may be supplied through
edges of outlet 38 f and:- inlet 311 should be‘fabout‘
the conduits 2l, 28, is introduced» intothe lift
tank- andpasses upwardlythrough the lift pipe
28; ei’f‘ecting- suspension- and 'lifting or' the cata
lyst». The- catalyst settlesA ontoa bed offsolidsin
'l0-'l5 degrees with theA horizontal; asin'di'cated
on Figure 2. By locating atëleastmost; or. theA
dischargeaperture sof? conduit 35i i outside this; ree
giom. the:l catalysttintroducedza through the: corr:-
2,656,306
8
duit 31 is preferentially withdrawn from the box
to that introduced through the conduit 3l. The
level of the discharge aperture of the conduit 3i
is located above the withdrawal aperture so that
the catalyst introduced through the conduit 3l
forms a bed which covers the withdrawal aper
ture. The catalyst forms a free surface at the
angle of repose of the material. This ranges
from about 25-45 degrees, broadly, and is usually
about 30 degrees. When sufficient catalyst is
introduced through the conduit 31 to maintain
the surface level of the bed of catalyst in the
combining box 33 up to the outlet of the con
duit 3|, the catalyst flow through the conduit 3l
is restricted or stopped. When suñicient cata
lyst is not introduced through the conduit 31 to
maintain the level constant, the bed surface pulls
away from the outlet aperture of the conduit 3 i,
allowing catalyst to tumble out of the conduit
and roll down the surface of the bed at a rate
which is fast enough to prevent the bed level
from falling any substantial distance.
It is preferred that under all conditions at
least some catalyst be withdrawn from the first
stream to maintain a continuous catalyst move
ment. Otherwise, the particles tend to pack
and bridge the conduit. Also, the particles in
the leg when stationary cool to a low tempera
ture. When the iiow is resumed, the cool cata
lyst tends to upset the thermal conditions in the
system. In order to insure continuous move
ment in the ñrst stream, the first stream is lo
cated laterally displaced from the withdrawal
stream so that an imaginary line connecting the
nearest point of the withdrawal stream with the
nearest point of the first stream forms an angle
with the horizontal which is greater than the
internal angle of catalyst flow. It is preferred
that the angle be only slightly greater than the
angle of internal flow, so that when the flow of
the second stream is high, the flow of the first
stream is reduced to a minimum necessary to
gas from one zone to another. The lift tank 26
is usually operated at advanced pressure, say,
for example, 5 p. s. i. (gauge). Hence, the seal
column in conduit 45 must be made long enough
to prevent the escape of any substantial amount
of the gas in the lift tank and also provide smooth
feeding of the catalyst downwardly into the lift
tank against the advanced pressure. The cata
lyst is discharged into the lift tank 26 from a lo
cation about the bed of catalyst therein. The
flow of the catalyst through the conduit 45 is
controlled by a valve 65 at the bottom of the
conduit. A suitable valve control is shown on
Figure 5. The seal column is introduced into
the top section of the lift tank 26 and discharged
into the bin 10. The bin 'I0 has an aperture 'Il
in the floor through which a stream of contact
material can pass. The flow through the aper
ture is controlled by the adjustable valve 6 5. The
valve plate has a multiplicity of orifices of vary
ing size in its surface. The flow rate of the con
tact material is adjusted by bringing the desired
orifice into alignment with the bin aperture.
The bin 'IG is constructed so that a large mass
of the contact material is exposed to the atmos
phere in the lift tank. If this were not done,
the pressure drop across the orifice in the valve
plate would be high and disrupt the flow of con
tact material therethrough. By equalizing the
pressure on opposite sides of the orifice, this diffi
culty is overcome.
The catalyst flow rate from the upper combin
ing box down to the lift tank is maintained, dur
ing normal operation, faster than the maximum
possible flow rate of the second stream, passing
through the conduit 3l. This insures that the
level of catalyst in the upper combining box will
not rise above the top of the box except during
unusual circumstances. For example, during the
period when fresh catalyst is being added, the
level may rise somewhat.
This occurs infre
quently, however, and is soon rectified when the
overcome the defects of a static stream. For
normal circulation is resumed.
example, if the internal angle is about 70 de
If the pressure in the separator ¿D is substan
grees, 75 degrees would be satisfactory in most ,
tially greater or less than atmospheric pressure,
cases.
the length of the substantially compact column
The conduit 38, depending from the upper
of catalyst in the side stream must be maintained
combining box, conducts the withdrawal stream
at least long enough to provide an adequate seal
downwardly into a lower combining box 39. The
between the settling zone and the combining zone
catalyst is discharged onto a bed of catalyst in 50 or between the settling zone and the fines-re
this box, similar to the discharge of the ñrst
moval Zone. This prevents the exchange of gas
stream onto the bed surface in the upper com
between the zones.
bining box. Since the ñnes are continuously
In less preferred form, a valve is installed at
removed, the catalyst inventory is depleted to the
the bottom of the conduit carrying the nrst
extent that, from time to time, fresh catalyst 55 stream of contact material. The valve is oper
must be added. A level indicator is usually in
ated automatioally by a controller connected to
corporated in the separator to determine the
level control means in the combining box, so as
need for fresh catalyst. The fresh supply is
to maintain a constant bed level in the box. The
added through the conduit 40 into a rising
operation of the elutriator is not aifected, there
bucket-type elevator 4| and is discharged there 60 fore, by a change in the flow rate of the first
¿from into the conduit 42, overflow box 43 and
stream, required to maintain constant level of
`conduit 44 into the lower combining box 39. The
the seal column between the combining box and
particles are withdrawn from the box 39 through
Vthe lift tank.
the conduit 45 as a substantially compact stream
Example I
.and introduced into the top of the lift tank 26. 65
The gas pressure in the elutriator is usually
The apparatus of the invention was incorpo
slightly higher than atmospheric, say, for ex
rated in a commercial NLUUG-15,000 bbl. per
ample, 0.5 p. s. i. (gauge), in order to provide
stream day hydrocarbon cracking system of the
suitable gas ñow through the vessel. The upper
continuous moving bed type. The catalyst was
combining box is maintained at substantially 70 synthetic spherical beads of the silica-alumina
the same pressure. The fresh catalyst is intro
chromia type. The catalyst particle size was
duced at atmospheric pressure. The column of
about 1A; inch diameter, and the poured density
catalyst between the two boxes is made long
about 45 pounds per cu. ft. The catalyst circu
enough to provide a suitable seal between the
lation rate of the system Was 365 tons per hour,
vessels and `prevent any substantial transfer of 75 With a side stream of about 15 tons being With
2,656,806
ld
the lfirst stream in said combining zone being -Io
eate'd far enough abo-ve the withdrawal location
drawn from the separator for use in elutriation.
The Ydimensions of the` combining box were:
`
`
»
in the bottom of thek zone, so that the contact
material introduced vfrom the first stream forms
a bed of material in the zone which covers the
withdrawal «location and forms a free surface ’at
sittin..
Y ritiri-m.
10 in.
o in. std. pipe.
'c
~-
Diameter of conduit carryi `
_ ___
__..
i >thdralwal
stream from upper combining box to lower
combining box _____________ __Y_«_____Á_____«____
8 in. std. pipe
Vertical distance downward from top of upper
combining box to the end of the conduit
carrying the first stream _____ _ __ ..... _
___«_
the angle of repose of the contact material, pass
4in. std. pipe
ing the contact material Withdrawn from the
bottom of said combining zone as av substantially
10. ycompact column into the top- of the feeding zone,
the length of the column being sufficient to pre
1 it.
vent the escape of any substantial proportion of
4boxV to center line of conduit carry g'
the lift gas through the column, the rate of with
Distance from opposite side wall of co bming
drawal of contact material from the combining
to center of withdrawal 'aperture in bòt- ,
_,
15 zone being substantially greater than the »maxi
mum possible flow rate of the second stream,
box to center of discharge apertureat lower
whereby the >contact material passed through
end of conduit carrying s cond 'stream lo.
cated in the roof of the com ining box ____ __ 4% in.
~
_
the lines-removal zone is selectively withdrawn
Gas pressure in upper combining box___
0.2 fp." 1._ ‘(gau‘ge)>
from the >combining zone and the surface level
Gas pressure in lower combining box_
Atmospherlc
Distance from bottom of lower combi
`
_
of the contact material in the combining zone 'is
to topof lift tank ___________________ __
35 f_t.
~
prevented from rising up into the fines-removal
Gas pressure in lift tank.
_____
_ _ ._
2.11 p. s. 1
Distance from side wall of upper com
stream___I ___________________ __~___
`
_
GasL Vressure in separatore..
1.0 H2O
Cata yst flow _through elutriatcr____________:_V_ 2-13 T. P H
Catalyst iiow through first stream, by~passing
elutriaton _________________________ _s ____ __.
zone.
`
s 2. In la process wherein a granular contact
material is passed cyclically through two ‘con
2-13 T. P. H.
, tacting zones, one being a reaction zone where
The examples and illustrations, given hereini
above, were supplied to illustrate the invention,
in it flows downwardly as a substantially 'com'
pact column while contacting a fluid hydrocar~
bon charge to eiîect conversion of said ‘charge to
and not to limit its scope. It is intended that the
scope of this invention be considered broadly
to cover all changes and modiñcations of the ex
gasiform products and the other zone being a
amples of the invention herein chosen «for pur
poses of disclosures, which do not 'constitute de
partures from the spirit of the invention.
We claim:
30 reconditioning zone wherein the contact mate-‘
l. »In a process wherein a granular contact mae
rial flows downwardly as a substantially corn
pact column while being contacted with a suit
able gas to eiîect its reconditioning for reuse in
said conversion zone ’and the contact material
terial is passed cyclically through two Contact_ 35 is withdrawn `as a >substantially compact 'column
ing zones, one being a reaction zone wherein it
flows downwardly as a substantially compact col
umn while contacting a iluid hydrocarbon charge
to. eiîect conversion of said charge to gasiforrn
from the bottom of one of said zones to a feed-v
ing zone wherein a suspension of the contact
material ‘is effected in an ‘upwardly liowing stream
of lift `gas and said contact material is liftedy
products and the other zone being a recondition 40 in said 'stream to a separation zone located above
the other of said contacting zones from where
ing zone wherein the contact material flows
the major portion of the 'contact material is
downwardly as a substantially- compact column _
gravitated `‘downv'vaïrdly from the bottom of said
while being contacted with a suitable gas to ef»g
separation zone as a substantially compact I'col
Í‘ect its reconditioning for reuse in said conver
umn to the top of the other of said contacting
sion zone and the contact material isk withdrawn
as a substantially compact column from the bot
zones, the improvement which comprises: gravi-‘
tom of one oi said zones to a feeding zone Where.
in a suspension of the contact material is effected
in an upwardly iiowing stream of lift gas and
tating a side stream of contact material down
wardly from the separation zone as a substan
from the bottom of said separation zone as a`
ond stream as a shower into a iineser'emoval
tion zone as a Substantially compact column,
top of the bed in the combining zone, withdraw-v
tially compact column, splitting the stream into
said contact material is lifted in said stream to a 50 two streams, gravitating the first stream 'down
wardly as a substantially compact column onto
separation zone located above the other of said
the top -of a substantially compact bed of the fna
contacting zones from where the major portion
teria-l in a combining zone, releasing the sec
of the contact material is gravitated downwardly
substantially compact column to the top 0i the 55, zone, passing a gas through the nues-.removal
zone to carry off the ñne particles entrain'e‘d
other of said contacting zones, the improvement
therein, gravitating the lines-free particles ¿from
which comprises: gravitating a side stream of
the bottom of the unes-.removal zone onto 'the
contact material downwardly from the separa
splitting the stream into two streams, gravitating 60 ing a stream o'f contact material from the bot
the iirst stream downwardly as a compacted co1
umn into the top of a combining zone, releasing
the _second stream as a shower into a nues-re
moral zone, passing a eas through the lines-re
moval Zone to Carry off the fine particles en 65
tom of the combining zone, the withdrawal
stream being laterally displaced from the ñrst
stream, so thatv an imaginary line >connecting the
nearest point of contact of the withdrawal stream
with that of the ñrst stream is disposed at an
trained therein, sravitatins the liasse-,free parti.
cles from the bottom ci the lines-removal zone to
the top of the ñrst combining zone, withdrawing
angle slightly greater than the angle of internal
flow, gravitating the contact material withdrawn
stream into said zone, but laterally displaced from
the location of introduction of the ñrst stream at
an angle about equal to the internal angle of
portion 'of the lift gas through the column, the
rate of withdrawal of Contact material from the
combining zone bei-ng `greater than the maxi-,
from the bottom of said combining zone as a
substantially compact column i'nt‘o the feeding
contact material from the bottûm oí said com
billing Zone at a location substantially directly 70 zone, the length of the column being sufficient
to prevent the escape of any substantial prot>
below the location of introduction of the second
contact material now, the discharge location of 75 mum possible new rate of the second stream,
2,656,806
il
12
whereby the contact material passed through the
gravitating the contact material withdrawn from
fines-removal zone is selectively withdrawn from
the combining zone and the surface level of the
contact material in the combining zone is main
the bottom of the second combining zone down
wardly as an elongated feed stream in substan
tained substantially constant.
3. In a process wherein a granular contact ma
terial is passed cyclically through two contact
tially compact column form and discharging the
feed stream into the feeding zone, the length
of the feed stream being sufficient to provide
smooth feeding of the contact material into the
ing zones, one being a reaction zone wherein it
feeding zone and prevent .the escape of any sub
flows downwardly as a substantially compact col
stantial amount of the lift gas from the feed
umn while contacting a fluid hydrocarbon charge 10 ing zone to the second combining zone.
to effect conversion of said charge to gasiforin
4. In a moving bed conversion system in which
products and the other Zone being a recondition
conduit means connects the bottom of one of the
ing zone wherein the contact material ñows
contacting vessels with a lift tank located there
downwardly as a substantially compact col
below, a lift pipe connects the lift tank with a
umn while being contacted with a suitable gas 15 separator located above the other contacting ves
to effect its reconditioning for reuse in said con
sel, and conduit means connectß` the bottom of
version zone and the Contact material is With
the separator with the top of the second con
drawn as a substantially compact column from
tacting vessel, the improvement which com
the bottom of one of said Zones to a feeding zone
wherein a suspension of the contact material is
effected in an. upwardly ñowing stream of lift
gas and said contact material is lifted in said
stream to a separation zone located above the
other of said contacting Zones from where the
major portion of the contact material is gravi
tated downwardly from the bottom of said sepa
ration Zone as a substantially compact column
to the top of the other of said contacting zones,
the improvement which comprises: gravitating
prises: conduit means for withdrawing granular
contact material from the bottom of the sepa
rator, a first downwardly directed conduit at
tached to said means, a combining box attached
to the bottom of the first conduit, a second down
wardly directed conduit attached to said means,
25' an elutriator attached to said second conduit,
valve means in said second conduit, a third con
duit attached to the bottom of said elutriator
connecting with the top of said combining box,
a withdrawal conduit attached to the bottom of
a side stream of contact material downwardly 30 said combining box and the top of said lift tank,
the length of the conduit being sunîcient to pro
pact column, splitting the stream into two
vide a seal column of substantially compact con
from the separation zone as a substantially com
streams, gravitating the ñrst stream downwardly
tact material adequate for preventing the escape
as a substantially compact column onto the top
of any substantial amount of lift gas from the
of a substantially compact bed of the material in 35 lift tank through the conduit, the discharge aper
a first combining zone, releasing the second
ture at the bottom of the second conduit being
stream as a shower into a fines-removal zone,
located substantially directly above the with
passing a gas through the fines-removal Zone to
drawal aperture at the top of the withdrawal
carry olf the fine particles entrained therein,
conduit, and the discharge aperture of the first
gravitating the lines-free particles from the bot 40 conduit being located laterally displaced from
tom of the fines-removal zone onto the top of
said withdrawal aperture, so that an imaginary
the bed in the first combining zone, withdrawing
line connecting the nearest point of the with
a stream of contact material from the bottom
drawal aperture with that of the discharge aper
of the ñrst combining Zone from a location sub
stantially directly below the location at which
the second stream is introduced into the zone,
the withdrawal stream being laterally displaced
ture of the Aiirst conduit forms an angle of about
'75 degrees with the horizontal.
5. In a moving bed conversion system wherein
a granular contact material is passed cyclically
from the ñrst stream, so that an imaginary line
through two contacting vessels, one being a re
connecting the nearest point of contact of the
action vessel and the other a reconditioning
withdrawal stream with that of the nrst stream 50 vessel, and contact material is withdrawn contin
is disposed at an angle slightly greater than the
uously from the bottom of one of the vessels
angle of internal flow of the contact material,
through connecting means to a lift tank located
gravitating the contact material withdrawn from
therebelow, suspended and lifted in a lift gas
the bottom of the ñrst combining zone down
through an upwardly directed lift passageway
wardly as a combined stream in substantially
which connects the lift tank with a separator lo
compact column form and discharging the com
cated above the other contacting vessel, sepa
bined stream onto the surface of a bed of the
rated from the lift gas in the separator, and
material in a second combining zone, the length of
gravitated as a substantially compact column
the combined stream between the first and sec
from the lower portion of the separator through
ond combining zones being sufñcient to prevent
60 a conduit to the top of the other contact vessel,
the transfer of any substantial amount of gas
the improvement which comprises, in combina
from one zone to the other, intermittently in
tion: at least one conduit attached to the bottom
troducing fresh contact material onto the top
of said separator, adapted to withdraw gravitat
of the bed of contact material in said second
ing contact material in substantially compact
combining zone, withdrawing a stream of con
column form, means for splitting the withdrawn
tact material from the bottom of the second com 65 contact material into two streams, a first down
bining zone from a location substantially di
wardly directed conduit attached to said means,
rectly below the location at which the fresh
a combining box attached to the bottom of said
contact material is introduced into the Zone, the
conduit, a second downwardly directed conduit
withdrawal stream being laterally displaced from
the ñrst stream, so that an imaginary line con
necting the nearest point of contact of the with
drawal stream with that of the combining stream
is disposed at an angle slightly greater than the
angle of internal flow of the Contact material,
attached to said means, an elutriator connected
to the bottom of said second conduit, valve means
in said second conduit, adapted to release gran
ular material into said elutriator as a shower,
means for passing a gas through said elutriator
to remove rlne particles from the granular ma
15
2,656,306
16
drawal aperture'of the connecting conduit in the
trol the flow rate of the contact material in the
bottom of the ñrst box, and the discharge aper
ture of the first conduitA being located laterally
displaced therefrom, so that an imaginary line
connecting the closest point of the discharge
aperture of the ñrst conduit with that of the
Withdrawal aperture of the connecting conduit is
located at an angle of about riâ-degrees, and in
addition, the discharge aperture of the ñrst con
conduit, a low pressure vessel located above said
duit is located at a level suiiîciently above the
withdrawal aperture, so that an imaginary line
drawn from the closest Ipoint ol' the discharge
aperture to the withdrawal aperture at an angle
of about 30-degrees with the horizontal passes
combining box, ya conduit connecting the bottom
of said low pressure vessel with the top of the
said combining box, so as to direct contact ma
terial downwardly from said low pressure onto
the surface of the bed of contact material in said
combining vessel directly above the withdrawal
conduit.
Y
11. In a system wherein a granular contact
material is passed cyclically through two contact
ing vessels, one being a reaction vessel and hav
ing spaced apart reactant inlet and outlet means,
a contact material inlet at its upper end and a
over the withdrawaln aperture, a fresh contact
contact material outlet at its lower end, and the
material conduit attached to the top of the sec
other being a regeneration vessel having spaced
ond proportioning box adjacent the connecting
apart gas inlet and outlet means and a contact
conduit, a se'al conduit :connecting the bottom of
material inlet at its upper end and a contact ma
the second box with the top of the lift tank, be
terial outlet at its lower end, conduit means con
ing long enough to provide a substantially com~ 210V nected to the -outlet of one of the vessels for
'pact column of contact material adequate to
withdrawing a compacted column from the bot
prevent the transfer of any substantial amount
tom of the vessel to a lift tank wherein suspen
of gas from the lift tank through the conduit,
sion of the material is eifected in an upwardly
the discharge aperture of the fresh contact ma
ñowing stream of gas and the material conveyed
terial conduit being located substantially direct 25 upwardly through a lift -pipe to a separator and
ly above the aperture of the seal column in the
then gravitated downwardly through a conduit
bottom of the second proportioning box, the dis
to the inlet on top of the other vessel, the im
charge aperture of the connecting conduit being
provement which comprises: a ñrst conduit de
laterally displaced therefrom so that an imag
pending from said separator, a combining box
inary line connecting the nearest point of the
attached to the bottom of said conduit, located
discharge aperture with that of the withdrawal
at a level substantially above said lift tank, a
aperture is located at an angle of about 65-80
second conduit attached to the bottom of said
degrees with the horizontal, and in addition, the
separator, an elutriator 'attached to the bottom
discharge aperture of the connecting conduit is
of said second conduit, said elutriator located at
located at a level sufñcicntly above the with
a level above said combining box, a valve in said
drawal aperture, so that an imaginary line drawn
second conduit, a third conduit connected be
from the closest point of the discharge aperture
tween the bottom of said elutriator' and top of
to the withdrawal aperture lat an angle of about
said combining box, a seal conduit connecting
¿iO-degrees with the horizontal passes over the
between the 'bottom of said combining box and
withdrawal aperture.
40 the?top of said lift tank, the length being suf
9. Apparatus for transferring a granular con
ñcient to provide a substantially compact col
tact material from a low pressure vessel to a high
umn of granular material adequate to prevent the
pressure vesselY comprising in combination: a
escape of any ‘substantial quantity of lift gas
`combining box, a downwardly directed conduit
through the conduit, the discharge aperture of
with its lower end projected into the top of the > the third conduit being located substantially di
box, ra withdrawal conduit attached to the bot
rectly above the withdrawal aperture of the seal
tom of the box, said withdrawal conduit laterally
conduit, the discharge aperture of the ñrst con
displaced from said first conduit, a high pressure
duit being located laterally displaced therefrom,
vessel located at the bottom of said withdrawal
so that an imaginary line -connecting the nearest
conduit, the withdrawal conduit being at least 50 ypoint on the discharge aperture with that of the
long enough to feed contact material into the
withdrawal aperture forms an angle with the
vessel against the advanced pressure therein, a
horizontal of -about 75 degrees, and, in addition,
low pressure vessel located above said combin
an imaginary line drawn from the closest point
ing box, and a conduit connecting the bottom 0f
of the discharge aperture to the withdrawal aper
said low pressure vessel with the top of said com 55 ture at an angle of about 30 degrees passes over
bining box, so as to permit contact material to
the withdrawal aperture, the cross-section of the
be charged from said conduit onto the surface of
seal conduit being substantially larger than the
a bed of catalyst in the combining zone.
cross-section of the third conduit.
l0, Apparatus for transferring a granular coni
l2. The method of transferring a particle-form
tact material from a low pressure vessel to a 60 contact material from a low pressure zone to a
high pressure vessel comprising in combination:
a combining box, va downwardly directed conduit
with its lower end projected into the top of said
box, Iadapted to feed a continuous column of con
tact material into the box and maintain therein 65
the surface of a bed of the material, a withdraw
al conduit attached to the bottom of the box, said
withdrawal conduit laterally displaced from said
ñrst conduit, a high pressure vessel located at the
high pressure Zone which comprises: gravitating
contact material downwardly from said low pres
sure zione in substantially compact columnar
form, introducing the contact material into a
combining zone at a first location, so as to form
a bed of solid material in said zone, introducing
a second stream of contact material into said
combining zone at a second location adjacent
said first location, so as to drop onto the surface
bottom of said withdrawal conduit, the withdraw 70 of the bed of Contact material in said combining
al conduit being at least long enough to feed
zone, withdrawing a substantially compact coln
contact material from the combining box into
umn of contact material downwardly from the
the highpressure vessel against the advanced
bottom of said combining zone at a third loca
pressure therein, valve means located at the lower
tion, substantially directly below said second loca
end of said withdrawal conduit, adapted to con 75 tion but laterally displaced from said ñrst loca
2,656,306
~
17
18
tion, so as to preferentially withdraw from the
whereby the escape of gas from the high pressure
zone is substantially prevented.
combining zone the contact material supplied by
said second stream of contact material, and dis
l5. In a process wherein a granular contact
charging the compact column of contact mate
material is passed cyclically through two contact
rial withdrawn from said combining zone into the Ul ing zones, one being a reaction zone wherein it
high pressure zone, the length of said column
ñows downwardly as a substantially compact co1
being suñicient to provide a substantially com
umn while contacting a fluid hydrocarbon charge
pacted seal leg of contact material, whereby the
to eiïect conversion of said charge to gasiform
escape of gas from the high pressure Zone is
substantially prevented.
products and the other zone being a recondition
10 ing zone wherein the contact material flows
13. The method of introducing a particle-form
downwardly as a substantially compact column
while being contacted with a suitable gas to effect
comprises: gravitating a substantially compact
its reconditioning for reuse in said conversion
column of contact material downwardly into a
zone and the contact material is withdrawn as
combining zone at a first location, so as to form 15 a substantially compact column from the bottom
a bed of solid material in said zene, introducing
of one of the zones to a feeding zone wherein
a suspension of the contact material is effected
a second stream of contact material into said
in an upwardly ñowing stream of lift gas and
combining zone at a second location adjacent said
said contact material is lifted in said stream to
ñrst location, so as to drop onto the surface of
the bed of contact material in said combining 20 a separation zone located above the other of said
contacting zones from where the major portion
zone, withdrawing a substantially compact col
of the contact material is gravitated downwardly
umn of contact material downwardly from the
from the bottom of said separation zone as la sub
bottom of said combining zone at a third loca
contact material into a high pressure zone which
stantially compact column to the top of the other
tion, substantially directly below said second loca
of said contacting zones, the improvement which
tion but laterally displaced from said ñrst loca
comprises: gravitating a substantially compact
tion, so as to preferentially withdraw from the
column of contact material downwardly into a
combining zone the contact material supplied by
combining zone at a ñrst location, so as to form
said second stream of contact material, and dis
a bed of solid material in said zone, introducing
charging the compact column of contact material
withdrawn from said combining zone into the 30 a second stream of contact material into said
combining zone at a second location adjacent
high pressure zone, the length of said column
being sufñcient to provide a substantially com
said ñrst location, so as to drop onto the sur
face of the established bed of contact material
pact seal leg of contact material, whereby the
in said combining zone, withdrawing a substan
escape of gas from the high pressure zone is
tially compact column of contact material down
substantially prevented.
wardly from the bottom of said combining zone
14. The method of introducing a particle-form
at a third location, substantially directly below
k¿contact material into a high pressure Zone which
said second location but laterally displaced from
comprises: _gravitating a substantially compact
said ñrst location, so that an imaginary line con
column of contact material downwardly into a
combining zone at a ñrst location, so as to form 40 necting the nearest point of the column of con
tact material supplied to the combining zone with
a bed of solid material in said zone, introducing
the nearest point of the column of contact mate
a second stream of contact material into said
combining zone at a second location adjacent
rial withdrawn from the combining zone forms
an angle of about 65-80 degrees with the hori
said first location, so as to drop onto the sur
-face of the established bed of contact material in
’ zontal, and discharging the compact column of
said combining zone, withdrawing a substantially
compact column of contact material downwardly
contact material withdrawn from said combin
ing zone into the high pressure zone, the length of
said column being suiiicient to provide a substan
from the >bottom of said combining zone at a
tially compact seal leg of contact material, where
third location, substantially directly below said
second location but laterally displaced from said 50 by the escape of gas from the high pressure zone
is substantially prevented.
ñrst location, so that an imaginary line connect
ERIC V. BERGSTROM.
ing the nearest point of the column of contact
EDWARD R. SORF.
material supplied to the combining zone with
the nearest point of the column of contact mate
References Cited in the ñle of this patent
rial withdrawn from the combining zone forms
UNITED STATES PATENTS
an angle of about 65-80 degrees with the hori
zontal, and discharging the compact column of
Number
Name
o
Date
contact material withdrawn from said combining
2,494,794
Bonnell __________ -_ Jan. 17, 1950
zone into the high pressure zone, the length of
2,546,625
Bergstrom _______ __ Mar. 27, 1951
said column being sufficient to provide a substan 6 O 2,561,409
Ardern __________ _.- July 24, 1951
tially compact seal leg of contact material,