Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
9~'7
- 2
Background of the Invention:
lhis inveiltion relates to a procexs for pre~)lri~lg
olefills SUC}l as e-tllylene, propylerle, alld the Like ftom
heavy petroleulll oil l~y usc of an eYtcrnll.l tlea~ing tyr)e
tubular reactor.
The term "heavy petroleum oil" used in the present
invention is meant to include crude oil, atmospheric pressure
residual oil, and reduced pressure residual oil.
Olefins such as ethylene, propylene and the like
have long been produced on an industrial scale by use of an
external heating type tubular reactor, wherein naphtha has
been used as the raw material J while the crude oil, heavy
oil and the like, which contain nonvolatile matter, have
not been used as the raw material due to severe coking in
the thermal cracking process and in the quenching process
for a produced gas.
As a process for the preparation of olefins from
heavy petroleum oil as the raw material, there are kno~n
processes which use a fluidized bed and which use a high
temperature medium stream. The process which uses the
fluidized bed includes a process which uses a moving
fluidized bed [Kagaku Kogaku (Chemical Engineering), Vol.
40, No. 7, pp. 358 - 362 ~1976)], and a process l~hich uses
a spouted bed [Kagaku Kogaku (Chemical Engineering), ~Jol.
40S No. 7, pp. 340 - 346 ~1~76)]. Ho~rever, tllese pl`OCeSSeS
have such problems that quenching~ of the proclucecl gas, ~rllich
47
-- 3 --
is important in the preparation of oleflns, is difflcult
to be effected, and that thermal cracking of heavy petroleum
oil mus~ be carried out in a residence time of about one
second at a relatively low temperature o about 750C,
because it is difficult to make the resldence time le5s
than one second.
On the other hand, according to the proce~s which
uses a high temp~rature medium stream ~Kagaku Kogaku
(Chemical Engineering), Yol. 40, No. 7, pp. 354 - 357
~1976)J, a combustion flame which uses oxygen and fuel as
a heating medium results in high cost, since the high
temperature superheated steam is used as the dilution
st~am for tempera~ure con~rol. Moxeover, a high yield
of ace~ylene according ~o the aforesaid process makes it
unsuitable as a process for the preparation of ethylene.
Brief Summar _ the Invention:
An object of an aspect of this invention is to
provide a process for continuously preparing olefins from
hea~y petroleum oil by use of an external heating type
tubular reactor without coking~
An object of an aspect of this invention is to
pxovide a process for preparing olefins from heavy petro-
leum oil at high yield.
An aspect of the invention is as follows:
A process for preparing olefins from heavy pe~ro-
leum oil, said heavy petroleum oil being mixed with steam
-- 4
and fed to a tubular reaction zone externally heated
for the preparation of oleEins, which comprises mixlng
said heavy petroleum oil with superh~ated steam at a
steam-oil ratio in -the range of ~rom ~ to 7, and
indirectly heating the resulting m:lx~ure so that th~
temperature at the outle-t of cl r~action zone may be in
the range of from 700 to 950C at a xesidence time of
from 0.01 to 0.1 second in the react:ion zone.
Brief Descri tion of the Dra ~ -
Fig. 1 is a flow sheet showing one embodiment
of the process of the present invention. Fig. 2 is a
diagrammatic sectiona~ view showing an example of a raw
material feeding mechanism used in the practice of the
process of the present invention.
Detailed Descri tion of the Pre~erred Embodiments:
According to the present invention, an external
heating type tubular reactor is used. The reactor con-
sists of a hollow tube and is provided with a raw material
feeding mechanism at the top thereof. The raw material
~eeding mechanism used may be of any type so long as the
heavy petroleum oil is atomized by a superheated steam
above 750C so that fine particles of the heavy petro-
leum oil may be homogeneously mixed with the superheated
steam, preferably of the type shown below. The tubular
reactor preferably has an inner diameter of from 3 to
15 cm~ and a length of
from 3 to 30 m. The reactor may be of a str~ight tube or
o-f a hairpin-shaped tube, alld may be installed ver~isally
or horizontally. '['lle tllbular reactot may aLso l)e in~;till1.ed
plurally in a furnclce.
The heavy petroleum oil fed frolll the raw material
feeding mechanism as an atomized mixture with the superheated
steam above 750C is subjected to cracking, while being
mixed with the high temperature superheated steam. Therefore,
neither deposition of carbonaceous substances nor coking
on the inner wall of the reactor takes place. The heavy
petroleum oil to be introduced into the raw material feeding
mechanism is fed thereinto at a temperature lower than 400C
in order to prevent coking in the nozzle.
The tempe-rature of the superheated steam is
generally above 750C, preferably in the range of from 750C
to 1200C. Use of superheated steam above 750C provides
the heat required for the cracking of the heavy petroleum
oil, resulting in preventing coking onto the inner wall of
the reactor, and in achieving a continuous operation. When
the temperature of the superheated steam is lower than
750C, coking onto the inner wall of the reactor takes
place. When higher than 1200~C, costs of the superheated
steam hecome higher, while the effectiveness in preventing
coking onto the inner wall of the reactor is not further
increased.
9~7
A mixing ratio of the superheated steam and -the
heavy petroleum oil is generally in the range of from 2 to
7, preferably 3 to 5 as a stcam-oil ra-tio ~moles of ~12O in
the superheated steclm/carbon atOllls itl ~he ~leaVy p~rOl~UIII
oil). When the steam-oil rat:io i.s less than 2, allloun~s of
both steam and heat given from other than thc reactor
become insufficient, resulting in a reduction in both the
degree of cracking and yields of ethylene, propylene, etc.,
and in coking within the tube. When greater than 7, the
amount of unreacted steam is increased, and heat loss is
also increased with no economic advantages.
The atomized mixture of the heavy petroleum oil
and the superheated steam is heated indirectly externally
to a temperature of from 700 to 950C, preferably 750 to
900C at the outlet of the reactor while flowing through
the tubular reactor. The residence time in the reactor is
in the range of from 0.01 to 0.1 second, preferably 0.03
to 0.06 second. As a result, the heavy petroleum oil is
subjected to thermal cracking to be converted to gaseous
components such as lower olefins, hydrogen, carbon mono~ide,
arbon dioxide and lower saturated hydrocarbons, vapors or
mists of various heavy hydrocarbons, and the like.
~;~ When the temperature of the fluid at the outlet
o the reactor is lower than 700C, there is SUC}I a tendency
that yields o olefins are reduced and coking onto the
inner wall of the reactor takes place. I~hen higher than
900C, the amounts of carbon mono~iclc, carbon ~io~ide and
hydrogen are increased, atld the yields of lower olefirls
such as ethylene, and plopylenc are reduc~d. ~ ell ~h~
residence time in the reactor is l~ss th.lll 0.01 second,
cracking of the heavy petrolcum oil bccornes insuf~icient.
When greater than 0.1 second, there is such a tendency that
the yields of lower olefins such as ethylene and propylene
are reduced, and coking onto the inner wall of the reactor
takes place.
A mi~ed fluid produced by thermal cracking in the
tubular reactor is quenched in an extremely short period of
time, for example, less than 0.05 second to such a tempera-
ture of from 500 to $00C that the thermal cracking reaction
is substantially stopped. The aforesaid quenching process
may be carried out according to the conventional processes,
for example, those disclosed in Japanese Patent Publication
No. 573/1966, Japanese Patent Laid-open Publication No.
110889fl980, etc.
One embodiment of the present invention will be
illustrated with reference to the accompanying drawings.
In Fig. 1, steam at 5 to 10 kg/cm gauge is introduced from
line 1 to a superheater 2, and heated to form superheated
steam at a temperature above 750C, preferably of from 750
to 1200C. The superheated s-team is introduced through line
3 to a raw material feeding ~lechanislll 5. On the other hand!
heavy petroleum oil as the ra~,r material is preheated to a
temperature belo~ 400C and in-troduced through linc 4 to
the raw material feeding mecharlisltl. A steam-oil ratio is
set in the range o~ ~rom 2 to 7, pre~lably 3 to 5. Ihe
raw material feeding mechanislll 5 may l)e o~ y type sv lon~
as the heavy petroleum oil as thc raw matctial CiLtl ~e
atomized to form an atomized miYtu-~e with thc superheated
steam, preferably of -the type show-ll in Fig. 2.
In Fig. 2, 11 represents an atomizer block, 12 a
nozzle for use in heavy petroleum oil as -the raw material,
and 13 a nozzle for use in the superheated steam ~hich
surrounds the nozzle 12. The tip of the nozzle 12 extends
a little forward of that of the nozzle 13, whereby atomization
of the heavy petroleum oil as the raw material can preferably
be effected to form an atomized mixed stream, in which the
heavy petroleum oil and the superheated steam are homogeneously
mixed.
The heavy petroleum oil as the raw material and the
superheated steam, which are atomized and mixed by use of
the raw material feeding mechanism 5, are fed into a -tubular
reactor 6 in a furnace 7 preferably at a mass velocity of
from 0.6 to 11.0 kg/hr/sectional area ~cm2) of the tubular
reactor. The mixed stream of the heavy petroleum oil and tlle
superheated steam is hea-ted with a combustion flame in the
furnace 7 passing through the tubular reactor 6 at a residence
time of from 0.01 to 0.] second, preferably 0.0~ to ().06
second, to reach a temperature of from 700 to 950C, prefer~bly
750 to 900C at the outlet of the reactor 6. The pressure
at the outlct of the r~actol 6 is l)-r~ferably in the range
of from 0 to 1 k~/cm2 ~ ILlge.
The mixed stre.llll resllltillg ~rom the r~actor 6 is
passed to a quenchel 9 via lirle 8 to be quenched to a
temperature of from 500 to 600C, so that thermal cracking
may substantially be stopped. The mixed stream resulting
from the reactor 6 should be reached to the quencher in less
than 0.05 second. The quenching procedure may be performed,
for example, in the manner below.
The mixed stream resulting from the reactor 6 is
introduced into the quencher 9 at a mass velocity of from
50 to 120 kg/m2/sec, and quenched indirectly to a temperature
of from 500 to 600C within 0.05 second to stop the thermal
cracking reaction and to generate high pressure steam for
recovery of heat energy. A direct quenching process, in which
a hydrocarbon oil for quenching is injected into the mi~ed
stream resulting from the reactor 6, is also widely known.
The quenched mixed stream is withdrawn from line
10. The resulting mixed stream has the following composition:
H2 0.6 - 1.6 ~ by weight
CO 0.8 - 9.0 ~
C2 0.3 - 6.0 "
CH~ 8.0 - 22.0 "
C2H6 2.0 - 6.0
C2H4 1~.0 - 31.0 "
947
- 10 -
C2~12 o - 0.7 ~ by weight
C3H8 0.1 - 0.7 "
C3~16 2.0 - 10.0 "
1,3-C4~16 1.0 - ~.() "
Other C4 o 7 - 3 "
Liquid 27 0 - 55 0 "
substances
The mixed stream is separated into its respective
ingredients by the conventional procedure.
The process of the present invention can be applied
temporarily to the thermal cracking of naphtha 9 kerosine~
gas oil, and the like. Therefore, even in the case where
the necessity to temporarily stop the feeding of heavy
petroleum oil to the reactor occurs, the aforesaid operation
can be continued with the use of light petroleum oil without
changing operating conditions and then by replacing light
petroleum oil with heavy petroleum oil for normal operation.
In accordance with the present invention, olefins
are produced from heavy petroleum oil without coking onto
the inner wall of the reactor by selecting specified thermal
cracking conditions by use of the e~ternal heating type
tubular reactor, resulting in high yields of olefins and a
long period of continuous operation.
E~amples of the present invention will be sho~n
below along with comparative e~amples.
9~
Examples 1-10, Comparative Examples 1-14:
A tubular reactor having an inner diameter of
~0 mm and a heating length of 1 m, on top of which a two-
fluid nozzle of the type showrl in E:ig. 2 is mounte~, is
installed vertically in the furnac0, and steam superheated
by a superheater and heavy pe-~:roleum oll are Eed to the
two-fluid nozzle to be atomized and mixed, forming a mixed
stream. The mixed stream is subjected to thermal cracking
to form olefins, hydrogen, other various hydrocarbons, and
the like.
The heavy petroleum oils used are shown in Table 1.
The operating conditions, composition of produced
gases, and conditions of operation for each example are
shown in Table 2.
9~7
- ~2 -
r~Lb 1~ L
~ ~tllo ~ r .l. c l~ c ~l
KuwaLtpressurepre.C.~Jurc
crudere~idtlaLr~s klu~t 1
I oLl (MiddLe oiL (M:Lddlc
East crudeEas~ crude
oil) oil)
Specific gravity (22/4C) 0.8532 0.9395 1.029
Moisture (vol. %) 0.05 0.1
Residual carbon (vol. %) 4.82 9.07
Elemental analysis (vol. %)
C ~35.08 85.09 ~5.12
12.05 `11.75 11.17
S 2.93 2.9 4.9
~ 0.1 0.2 0.45
Vanadium (ppm) 24 50 150
¦ Nickel (ppm) 11 ' 25 45
4~
Table 2
I Example 1 ¦ Exa~ple 2I Example 3I E~ample 4
Heavy petroleum oil as I Kuwait ! Kuwalt I Kuw~lt I Kuwait
raw material orude oil ¦ crude oil ~ oru~e olll cr~de oil
Temperature of l .
superheated steam (C) I 1000 1000 ¦ 1200
¦ Te~perature at the O , 750 j 800 ~ 900 1 800
outlet of the reactor ( C)
Steam-oil ratio (moles
of H20/carbon atoms) 1 2 1 ~ I 4 I 5
_ . ~ ,
Residence time ~sec) I 0.06 0.1 1 0.01 ¦ 0.03
Mass velocity
(kg/hr/sectional area 1.8 0.9 8.1 2.8
~cm2~ of the reactor)
. ... .
¦ H2 (weight %~i 0.7 0.9 0.8 0.9
CO ( " ~I 1.1 2.3 1 1.8 2.3
2 ( " ~I 0 4 1.2 1 0.8 1.2
~ CH4 ( 71 ~I15.8 19.3 1 18.8 17.2
I ~ C2H6 ( " )~ 3.8 4.2 1 4.4 5.1
.~ C2H4 ( " ) 18.0 26.0 ' 27.2 29.3
~ ~ C2H2 ( " ), 0.2 ~0.3 ' 0.4 0.3
1~ O C3H8 ( " )¦ 0.4 10.3 1 0.2 0.4
I o C3H6 ( " ~¦10.0 ¦ 5.C 3.1 7.4
: g 1'3-C4H6 ~ " )I6.8 2.0 1 2.4 4.0
Other C4 ( ~ )'2.2 1.2 - 2.1 2.1
: hydrocarbons I i
Liquid ( " )I40.6 37.3 1 32.Q 29.8
substances l ~
_ . .._ . __ ~
Conditions of operation Operation Operation Operation Operation
(Coking, period of . for 8 hrs for 8 hrs for 8 hrs for 8 hrs
continuous operation, Cokin~ at
etc.) the outlet
. of the tube _ .
TCIb1e 2 ~COnt. ~
Comyarat-ive Comparat:i,ve ('o~rlpar~ ive C'otllE~ar.l~ive
~.Y.1111l~ L~ 1 E-~LI(;IP 1.~! 2. ~ IIIP 1~ 3 ~ rlr~P Le ~j
___............ __ ~ .,_ ._ __ . . ~. _ _ . _. _ ... , . . .. _ , ~ _ . . _ . _.. _ , .. .. ._~ . ____ . _ .
Heavy petroleum oil as Kuwait K~lwai~ KllwaL~ Kuwait
raw material cru~le o~ rude o~ rucle oL:I. crl~cl~! oi:l
Temperature of 800 800 700 lOOO
superheated steam ( C)
Temperature at the
outlet of the reactor (C) 680 950 SOO 900
8team-oil ratio (moles 2 , 2 4 4
of H20/carbon atoms)
.
Residence time (sec) 0.06 0~03 0.1 0.008
Mass velocîty
(kg/hr/section~l area I 1.9 ~I 3.0 0.9 10.1
~cm2~ of the reactor) ~ '
i f (weight ~) 0-3 1 1.4 ' 0.7 0.8
CO ( " ) 0.7 ` 7.8 2.1 ~1.7
2 ( " ) 0.2 4.5 1.1 0.8
12.1 21.2 17.3 18.5
( ) 2.4 : 3.7 3.S 4.2
, ~1 '.
C2~4 ( ~- )15.7 22.2 24.3 ~ 27.0
, h I C2H2 ( 1l ) - ,0-5 0.2 0.4
C3H8 ( )0.4 ~ 0.1 ~0.4 0.2
1 3 6 )9.8 2.3 5.7 3.6
3~C4H6 ( )7.2 1.9 2.3 2.7
¦ hydrocarbons ( " ) 2.7 1.0 ~ 1.3 ~.3
bstances ( ) 4S.5 33.4 40.S 37-~
__ ___ . _
¦ Conditions of operation IOperat~oll Operation Operatioll Operation
I (Coking, period of i for 8 hrs Eor S hrs i for S hrs for S hrs
continuous operation, ICoking all 1 ¦ Pod~
etc.) lover the I the inn~r
¦inner wall I w~l L o f th~
I~ the tube I
47
Table 2 (cont . ~
Icompara~ive!co~parative Comparatlvel Exam 1 5
¦ Example 5 I Example 6 Exa~lple 7 ¦ P
_ __ _ _ ; _ ~_ . ......... A ~_ I _~_
Heavy petroleum oil ~s ¦ Kuwait Kuwalt KU~it j~tmo5pheric
raw material ¦ crude oil crucl~! oll ~ru~e Oillpre~sure
~ t~ ~ re~idual oll !
I Temperature of
I superheated steam (C~ I 1000 1000 ¦ :L000 800
~ . _ ,
. .
Temperature at the l
ou~let of the reactor (C) 800 900 1900 750
_ .............. ! ---- __
Steam-oil ratio ~moles l l
of H2O/carbon atoms) 1 4 0.8 1 8 2 1.
. ~
Residence time (sec) ¦0.15 ¦ 0.01 ¦0.01 0.06
Mass velocity
(kg/hr/sectional area 0.6 13.3 7.4 1.8
(cm2) of the r~actor)
. _ .___
! ~2 ~weight %) 1.0 ¦ 1.2 1 0.6
CO ( " ~ 3.1 12.1 11.1
l ~ C2 ( " ) 1.8 1 11.1 10.5
¦ x CH4 ( " ~I20.0 ¦ ,18.2 ¦14.7
¦ ~ C2H6 ( " )I4 3 , ¦4.3 3.7
C2H4 , ¦ ,27 8 15.1
h C2H2 ( ~ 0.1 10.5 0.2
o C3H8 ( " ~!0 3 0.3 0.4
1 ~ ~ C3H6 ( " ) 4.0 j4.6 8.9
~: O 1'3-C4H6 ( " ) 2.0 !3.1 6.3
~: ~ Other C4 t " ) 0.8 ¦ 2.4 2.3
: ~ substances ( ) 40.1 34.4 46.8
_ . ,. . _._ .
: Conditions of operation Operation Coking Operation Operation
(Coking, period of for 8 hrs Incapable for 8 hrs for 8 hrs
oontinuous operation, Coking at of
. the outl.et operation
_ . of the l.. ube
_
- 16 -
Table 2 (cont .
.. .._ ~_
Exa~ple 6 Comparative I Comparati~e
Example 8 , Example 9
Heavy petroleum oil as I Atomospheric Atomospher$c~ Atomosyheric
raw materialpressure prcssurc I pre.~ re
_ ____ residual oll re~idual oil
Temperature of
superheated steanl (C) 1000 700 ¦ 1000
_. _ __ . _ _ __ _ _
Temperature at the
ou~let oE the reactor (C) 850 850 700
.~ .. _ _ - .. _ _ . .
Steam-oil ratio (moles l
of H20/carbon atoms) 1 4 4 ~ 4
_ - _ __ !
Residence time (sec) ¦ 0.03 0 03 ! 0.15
_ . ~ _ .__ . _ _ . I
Mass velocity
(kg/hr/sectional area 2.8 2.8 0.6
(cm2) of the reactor)
, _ _
H2 (weight %) ¦ 0.9 0.8 ¦ 0.7
C0 ( " ) 2.4 2.3 1 2.3
2 ~ " ) 1.3 1.1 1.0
CH4 ( " ) 17.5 ¦15.8 ! 14.9
. C2~6 ( " ) I 4-2 1 3.8 1l 2.8
C2H4 ( " ) 24.3 21.2 20.8
o C2H2 ( " ) 0.2 0.1 1 ~
~ C3H8 ( " ) ¦ 0.3 0.3 1 0.5
.~ C3H6 ( " ) 6.8 7.0 8.0
: I ~ 1'3-C4H6 ( ) 3.5 3.4 3.7
hydrocarbons ( ) 1.9 1.7 2.1
: substances ( " ) 36.7 49.5 43,2
~ __ _ .. . ._
Conditions of operation
(Coking, period of
continuous operation,
: etc.)
_ _ . . ____ _ . . ~__ ____ _
g47
- 17 -
Table 2 (cont~)
j I Example 7 r Example 8 ¦ Y,xample 9
Hea~y petroleum oil as I Reduced I Reduced I l~educed
. pressure pressure pressure
raw materlal residual oil residu/ll oll residuaL oi~.!
Temperature of ¦ 1000 1200 900
. superheated steam ( C) ! ~
¦ outlet of the reactor (C) 900 800 ,50
¦ Steam-oil ratio (moles l
! of H2/carbon atoms) 1 4 5 4
- -- _ _ _
¦ Residence time (sec) I 0,03 0.01 ¦ 0.1
. Mass velocity
(kg/hr/sectional area 2.7 8.5 0.9
. (cm~ ) of the reactor) ~ _
H~ (weight %) ¦0.~ 0.8 1 0.7
CO ( " ~1 2.3 2.3 1 2.0
2 ( " )I 1.3 1.2 1.0
~ CU4 ( " ~I 16.2 16.8 8.2
oC2H6 ( " ) 3.2 3.2 3.0
2H4 ( " ) 22,3 22.4 1 15.1
. oC2~2 ( " )I 0.2 0.2 1 0.1
: o 3 8 ( ) 0.2 0.3 0.3
: .~C3~6 ( " ) 6.3 4.~ 5.0
:~ ~1~3 C4H6 ( ) 3.1 2.2 2.4
Other C4 ( " ) 1.2 1.0 I.0
hydrocarbons
Li~uid ( " ~1 42.8 44.8 61.2
substances I _ .
Conditions of operation Operation Operation
CCokingg period of for 8 hrs for 4 hrs
continuous operation,
etc.) Coking
9~7
- 18 -
Table ~ (cont . )
-r-~
F,~campl~ 10 ~ Comparative Compara~i~re
Ex~ ple 10 EY.ample 11
----~ ~
Heavy petroletlm oil asI Reduced I ~educed Reduced
raw material I pressure pres~u:rf3 pre~sure
_ _ I residu 1 oLl _ ~idual oLl re31dual oil_
Temperature of . .
superheated steam (C) :LOOO 1000 1~00
. .~ . .. .
Temperature at the
outlet of the reactor (C) ¦ 950 800
~ ._ . _
Steam-oil ratio (moles
of H20/carbon atoms) 4 4 5
, __ .
Residence time (sec) ¦ 0.030.03 0.008
. . . . __ .__
Mass velocity
(kg/hr/sectional area 2.9 2.6 10.6
(cm2) of the reactor)
- H2 (weight %~ 0.8 1.0 0.7
CO ( ") I 2.1 2.6 2.2
C2 ( "~ I 1.0 1.3 1.1
x CH4 ( ..) 1 9.8 12.8 15.8
g C2H6 ( "~ I 3.2 3.2 3.o
~ C2H4 ( ) ¦ 19.2 20.2 22.3
o C2H2 ( ") I 0.2 0.2 0.2
C3H8 ( "~ ! 0 3 0.1 0.2
o C H ~ ~ 5 1 3.2 4.5
1,3-C4H6 () ¦ 2.6 1.5 2.1
Other C4 ( " ) ¦ O 9 0.8 l.Q
substances ( ) ¦ 54.8 53.1 49.2
_
Conditions of operation . Operation
(Coking, period of for S hrs
continuous operation,
etc.)
_ . __. _ . , , _______ . . ____~__ _
- 19 -
Table 2 (cont . )
¦Comparatlve ~ Comparative Colnpatatlve
~E~ampLe 12 I Exanlple 13 ~xalllple 14
Heavy petroleum oll as ~Reduced ~ ~ecluc~d Redu~f~l
raw material pressure pressure pressllra
~_ __ _ l eSlllU9 _ _il _esldual ~ reci:Ldual. o:L;L
Temperature of
superheated steam (~C) 1200 1000 1~00
_ . _ .. _ ... ._ ___
Temperature at the
outlet of the reactor (C) ¦ 800 800 800
. ._ .... .. . . .. .
Steam-oil ratio (moles l I
of H2O/carbon atoms) ' 5 1 8 0.8
. ._ l _
Residence time (sec) 0.15 ¦ 0.03 ¦ 0.03
~- .._
Mass velocity
(kg/hr/sectional area 0.6 2.7 4.9
(cm2~ of the reactor)
- . ~ . ._,
H~ (weight %) 0.9 ~0.9
CO ( " -) 2.4 ~ 2.3
C2 ( " ) 1.3 ~ 1.2
CH4 ( " ) 16.3 ¦ 10.1
6 ( " ) 2.8 1 3.2
2H4 ( " ) 21.1 j 21.2
C2H2 ~ " ) 0.2 ~ 0.2
4~
.~C3~1~. ( " ) 0.2 0.3
uC8H6 ( " ~ 3.9 5.7
, C4H6 ( ) 1.9 2.7
Other C4 ( " ) 1.0 1 0.9
hydrocarbons
Liguid ( " ) 50.6 53.8
_ . . . . I
Conditions of operationOperation Operation Incapable o~
(Coking, period of for ~ hrs for 3 hrs operation
continuous operation9 due to
etc.) coking
_ .. , . _ ~
- 20 -
As is apparent: from the results shown i.n the
Examples and the Comparative E'xamples, the process o~ the
present invention is capable o~ preparirl~ olefitls ~rolll
heavy petroleum oil with high yielcls o:~ ol.cfins w-ithout
coking onto the i.nller wall of the reactor.
