Note: Descriptions are shown in the official language in which they were submitted.
7~73
,
This invention relates to composltions useful for
injecting into subterranean reservoirs to recover crude oil
therefrom and more specifically to petroleum sulonates obtain-
ed by reacting aromatic hydrocarbon with gaseous SO3.
Petroleum sulfonates have been prepared by a variety
of means, for example, sulfonated with sulfur dioxide (U.S. Patent
2,999,812), sulfur dioxide and chlorine ~U.S. Patent 2,197,800),
cleum ~U.S. Patent 2,845,455~, and sulfur trioxide ~U.S. Patent
3,183,183). U. S. Patents 3,215,628 and 2,815,370 teach the use
of specific hydrocarbon fractions. Other patents of lesser
interest include U. S. 2,174,508; 2,800,962; 3,173,864; 3,308,068;
3,244,622; and 3,418,239.
The prior art suggests that whole crude oil can be
sulfonated and used in oil production. (See U. S. Patents
1,822,271; 3,126~952; and 3,302,713 teaching the use of whole
crude sulfonates in secondary-type oil recovery and U. S. Patents
2,798,851; 2,953,525; and 3,198,832 teaching the use of such sul-
fonates in drilling muds). However, we are unaware of a teaching
as to ho~ this can be done or any co~ercial use of such a process.
Specific teachings of which we are aware require the removal of
the light and/or heavy ends and the use of only the middle cuts
to obtain the petroleum sulfonates.
There are a number of reasons for ~ractionating crudes
prior to sulfonation. Inter alia, it is difficult to obtain a
marketable product from asphaltenes which tend to form tarry
materials Which foul reactors and sometimes form coke-like
deposits, Also, the lighk ends are often aliphatics or light
aromatics Which will not produce the desired product.
2~ We have now discovered that commercially acceptable
~,; ~
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7~73
sulfonates can be prepared ~rom a variety of crude oils using
our processes~ While ~e were surprised to be able to prepare
sulfonates in good yields and wi~hout coking or the formation
of tarry products, we were pleased when we found that the sul-
fonates produced economic micellar sy,stems suitable for use in
oil recovery.
The upcoming "energy crisis" puts our invention in
context. T. M. ~effen ~Oil & Gas Journal, May 7, 1973, pp. 66-76)
indlcates that 55 billions barrels of addi~ional crude can be
recovexed ~ia tertiary recovery. Heretofore, tertiary recovery
processes Csee U. S. Patents 3,254,714; 3,307,628; 3,504,744;
3,261,399; 3,497,0a6; 3,506,070, 3,354,953; 3,330,344 and 3,348,
661 -- most using petroleum sulfonate surfactants) have all proved
unecono~ic because, inter alia, the cost of materials used made
the processes uneconomic and the amounts of oil recovered were
too small. Our process provides sulfonates at a price sufficiently
low to aid substantially in the commercialization of tertiary
oil recovery using secondary-type oil recovery techniques taught
in the above listed patents.
According to the present invention, a substantially con-
tinuous flow of sulfur trioxide in the gas phase, is reacted
with a hydrocarbon which can be either whole crude oil or topped
crude oil or mixtures thereof. The contack occurs in a reaction
zone fed by a substantially continuous flow of said hydrocarbon
at temperatures, pressures~ and other conditions as described
hereina~ter, and is followed by neutralization and possible
extraction of unreacted hydrocarbons. The invention thus offers
the substantial advantage of being able to produce valuable
29 petroleum sulfonates rom crude oils without fractionation
:. :
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(other than optional "topping" to remo~e lo~ boiling fractions,
usually paraffinic and not very reactive). The simplicity of
this technique permits the use o~ portable sulfonation facilities
which can manufacture petroleum sulfonates in the oil field.
Thus, the present invention o~fers the opportunity to manufacture
sulfonates for use in petroleum recovery by use of substantially
untreated recovered petroleum with all of the attendant advantayes
over existing techniques which require substantial refining prior
to sulfonation, use of selected fractions of pe-troleum in order
to provide sulfonates suikahle for preparation of micellar systems,
and the transportation from the producin~ field to the refinery
and then the sulfonation plant and thence to the point of use
in the ~ield~
The petroleum sulfonates of the present invention are
useful in a wide variety of applications, including the preparation
of cleaning compositions, frothing agents for oil flotation, and
other purposes to which petroleum sulfonates are conventionally
put. However, the most preferred application of the products of
the present invention is the preparation of micellar systems and
emulsions, especially those useful or the recovery of crude oil
from subterranean reservoirs. The petroleum sulfonates of the
present invention can be substituted as the surfactants in the
techniques taught in each of the petroleum recovery patents
mentioned above under prior art. In many cases, no further modi-
fications of the formulations taught in those patents will be
necessary. Where greater or lesser amounts of the sulfonates of
the present invention axe required, these amounts may be readily
determined by routine trial preparation of micellar systems and
~3 routine evaluation of such systems, e.g., by core ~looding tests.
c~/ - 3 -
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L7~73
The drawing shows a preferred embodiment o~ the sul-
fonation process wherein crude oil i5 first dried, then contacted
with sulfur trioxide and a Nash compr~ssor is used to compress
the effluent from the reaction zone. Sulfur dioxide (reaction
by-product from the sulfonation reaction) and light hydrocarbon
vapor ~light ends from the crude oil) act as diluents for the
reaction. Excess sulfur dioxide is contacted with water and
ammonia to convert the sulfur dioxide to bisulfite and sulfite
salts and these salts are admixed with the ammonium sulfonate.
A portion of the liquid from the reactor separator is cooled
and recycled back to the sulfonation reaction zone -- the
residue of the liquid is neutralized with an aqueous ammonium
hydroxide solution to obtain a substantially neutralized sulfonate
stream. This sulfonate stream is then permitted to phase separate
into an unreacted oil phase and a petroleum sulfonate phase
which is thereafter cooled, contacted with sufficient ammonia
to obtain a pH of about 7-1~ and is then filtered. The filtrate
is admixed with a cosurfactant to obtain a micellar dispersion.
The unreacted oil from the settler is used to extract the heavier
molecular wei~ht hydrocarbons from the light hydrocarbon vapor.
Starting Materials: Hydrocarbon Feed: - It is an
important aspect of the present invention that whole crude oil
or topped crude is sulfonated. Previous processes have sulfonated
gas oils without achieving the simplicity of the present invention.
Crude oils which are particularly useful for the practice of the
invention are those which are relatively high in aromatic content;
but, lubricating oil base crude~ ~low aromatic content) are also
acceptable.
2q The crude oil may be substituted with non-interfering
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substituents, e.g., NO3, C12, SO4, etc., but will preferably
be a hydrocarbon. Preferred crude oils are those with aromatic
portions having molecular weiyhts in the range o~ about 200 to
about 1000, more preferably about 300 to about 800, and most
preferably about 350 to about 500. The aromatic content of
the crude oil is preferably about 10 to about 95, more prefer-
ably about 20 to about 80, and most preferably about 25 to
about 50 weight percent aromatics as defined in American Petroleum
Institute Project 60 Reports 4-7 entitled "Characterization o~
Heayy Ends of Petroleum". Texas crudes, Libyan crudes, Louisiana
crudes, Wyoming crudes, ~ichi~an crudes t Illinois crudes, Oklahoma
crudes, Mississippi crudes, and Canadian crudes, are particularly
preferred as starting materials. Especially preferred are crude
oils wherein the aromatic portion has an aliphatic/aromatic
proton ratio o~ about 3 to about 20 and more preferably about
4 to a~out 18.
The "aliphatic to aromatic proton ratio" used in the
specification is measured on a carbon tetrachloride solution
of the sample using a 60 MHz nuclear magnetic resonance spectro-
~0 meter. The basic technique has been described by V. H. Lutherand H. H. Oelert, Erdon and Rohle, 24, 216 (1971). All those
protons which resonate with a chemical shift between 0 and 5
ppm from the tetramethylsilane internal standard are defined
as aliphatic protonst whose which have a chemical shift between
8.2 and 5 ppm are defined as aromatic protons. The American
Petroleum Institute Project 60 Reports 4-11 entitled "Character~
ization of Heav~ Ends o~ Petroleum" present data which show the
polynuclear aromatic content of crude oil distillates from
29 Was$on~ Texas; ~ilmington, Califoxnia; Red Wash, Utah: Recluse,
c~/ - 5 -
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Wyoming; Prudhoe Bay, Alaska; Gato Ridye, California; Ponca
City, Oklahoma; and Gach Saran, Iran. Other evidence for the
presence of polynuclear aromatics in crude oil is scattered
throughout the petroleum literature. I'he Chemistr~ of Petroleum
Hydrocarbons, B. T. Brooks et al, Volume I, Reinhold, 1954
discusses the concepts prevalent prior to 1954. Since that
time, additional wor] has been done on the higher boiling
crude fractions utilizing sophisticated analytical instrumentation
and today there is little doubt that polynuclear aromatics are
present in crude oils.
Topped crudes, e.g., those having a portion of the
hydrocarbons boiling below about 600F~ removed, can be utilized
in place of the whole crude oil.
- The hydrocarbon feedstock is preferably dried to a
water concentration less than about 1500 ppm and preferably
less than 1,000 ppm and more preferably less than 500 ppm.
Too hIgh of a water concentration causes the formation of sul-
furic acid with the SO3 and thus reduces the yield of petxoleum
sulfonate; it also adversely influences the phase separation of
unreacted hydrocarbon from the neutralized sulfonation mixture.
SO3 Diluent: The SO3 stream is diluted with gas,
eOg., SO2 and light hydrocarbon vapor (can be refined light
paraffins, light ends from the crude oil). Optionally, other
gases such as air, nitrogen,natural gas, or other dry gases
can be used. The ratio of the SO2 and light hydrocarbon vapor
to the hydrocarbon feed is 0.01 to about 10, more preferably
about .1 to about 6, and most preferably about 1 to about 2
moles of each of the SO2 and hydrocarbon vapor per 100 1bs of
2Q the h~drocarbon ~eed.
ch/ - 6 -
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The purpose of the diluent is to dilute the S03 in
order to promote a more even sulfonation reaction, e.g., to
reduce the amount of tri- and hiyher sulfonates produced.
Also, the S03 diluent is necessary to reduce the partial
pressure of the S03 in the reaction zone. An upper limit
of about 35 psi partial pressure of the S03 is generally pre-
ferred while the desired level is down around 5 psi. If the
hydrocarbon feedstoc~ is a topped crude oil ~i.e. very little
light hydrocarbon vapor is present), then the concentration of
~0~ is preferably high to obtain a desired partial pressure of
S03 in the reaction zone. While the S03 diluent will not ordinar-
~1~ solubilize the sulfonates in the unreacted hydrocarbons, it
has the addit~onal advantage of lowering the viscosity of the
reactIon products.
Excess diluent from the vapor phase of the reactor
separator is preferably scrubbed with water (can contain ions)
containing a basic compound, preferably ammonia, to convert any
S2 to tne salts thereof, e.gO bisulfite and/or sulfite. The
salts can be admixed with the petroleum sulfonate productA The
2~ S02 scrubber is preferably operated at a temperature to keep at
laast a majority of any hydrocarbon present as a vapor, i.e.
condensing hydrocarbon i~ the S02 scrubber is not desired~ Hydro
carbon vapor from the S02 scrubber is preferably scrubbed with
unreacted oil obtained from the phase separation of the unextract-
ed, neutralized sul~onate mixture to extract higher molecular
weight fractions from thiS stream. Thereafter the extracted,
light hydrocar~on can be flared, etc. and the unreacted oil
contain~n~ extracted hydrocarbons can be used in a refinery,
2~ etc.
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SO~ and Light Hydrocarbon Vapor Recycle: In a
vapor-liquid separating stage the effluent from the reactor zone
is separated into a vapor stream and a li~uid stream. ~t leas-t
a portion of the SO2 Yapor stream [comprised of SO2 and light
hydrocarbon vapor ~contains hydrocarbons having molecular weights
up to about 125 and preferably the a~erage molecular weight is
less than about 75]~ is recycled back to said reaction zone.
A portion of the li~uid stream from the reactor separ-
ator is cooled to reduce its temperature by about 3 to about
50~F. and preferably about 5 to about 30 and more preferably about
8 to about 15F. Said cooled stream is recycled back to mix
with the hydrocarbon stream being fed to said reaction zone.
Sulfonation Additives: To facilitate controlling
the equivalent weight distribution in the product mixture obtained
from the reactions of the invention, one or more sulfonation
additives can be added. These additives may be used either in
conjunction with or in the absence of the aforementioned diluent.
Such sulfonation additives are preferably aromatic hydrocarbons,
olefinic hydrocarbons, or oxygenated hydrocarbons, and preferably
have molecular weights in the range of about 200 to about 1000,
or more preferably about 300 to about 800, and most preferably
a~out 350 to~about 500~ Speclfic examples of such sul~onation
addit~ves include oxo alcohol bottoms (this is an oxygenated
hydrocarbon and is defined below), aatal~tic cycle oil ~defined
~n U. ~. Patent 3,317,422, Col. 1, lines 55 through 72), Ultra~
former ~olymer bott~ms ~mixtures of alkylated benzene and naphtha-
lenes~, and axomatics (such as those produced by the process of
U, ~. ~atent 3,31.7,422)~ The sul~onation additives can be used
2~ in amounts o~ about 0 to 20, preferably about 2 to about 15~ and
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more preferably about 4 to about 10 pounds o~ sulfonation additive
per 100 pounds o~ h~drocarbon feedstock, i.e. crude oil or topped
crude oil.
The sulfonation additives can conveniently be incorpor-
ated into the hydrocarbon feedstock be~ore it is sulfona-ted.
Therea~ter, normal sulfonat1on reaction procedures are followed.
The sulfonation additives are generally sulfonated ~or sulfated,
ln the case of oxy~enated hydrocarbons) and exit as part of the
product mixture.
The "oxo alcohol bottoms" are specifically debcribed
in the book "Higner Oxo Alcohols" by L. F. Hatch, Enjay Company,
Inc., 1957. Analysis of a typical oxo alcohol bottoms is (taken
from "Oxo Ether Alcohols," Industrial and Engineering Chemistry,
Bartlett, Kirshenbaum and Missig, Vol. 51, No. 3, pages 257-258):
Molecular weight 269
Oxygen, % 11.1
Carbon, % 75.2
Hydrogen, ~ 13.7
~ydrQxyl No., mg. KOHgb 204
Infrared spectra
Et~er peak at 9 microns Yes
Alcohol peak at 9.6 microns Yes
a Determined by cryoscopic method.
b By acetic anhydride-pyridine back-titration.
The components within the oxo alcohol bottoms can be alkoxylated,
e.g., about 1-50 moles of an alkylene oxide such as ethylene
oxide, propylene oxide, e~c. can be usad. Examples of commer-
cially available oxo alcohol bottoms are the C 8 Oxopolymer and
C-10 Oxopolymer products of Houdry Process and Chemical Co.,
~elaware City, Delaware; Monsanto oxo alcohols, e.g. oxo alcohol
29 100 and heavy oxo end~, Monsanto Company, St. Louis, Missouri, etc.
cb/
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Sulfur Trioxide: The sulfur trioxide useful with the
present invention can be of the usual commercial purity though
high purity or relatively crude materials may be used in special-
ized circumstances where warranted by the desired products.
The sulfur trioxide should be preferably substantially anhydrous
and should be ~ree ~rom substantial quantities of impurities
which would cause deleterious side reactions. About 3 to about
30, preferably about 5 to about 15, and more preferably about
8 to about 12 lbs. SO3 per lO0 lb. of hydrocarbon feedstock
is useful with this invention.
If the SO3 treat level is too hiyh, tarry by-products
may be obtained. In addition, inefficient oil recovery may be
obtained.
Reaction Catalyst- While no catalyst will generally
be employed with the present invention, known sulfonation catalysts
can be employed where desired.
Reaction Temperature: In order to obtain the preferred
product, the sulfonation reaction temperature should be about
120 to about 250F., preferably about 145 to about 220F, and
more prefera~l~ about 170 to about 190F. Temperatures lower
than 120F. may cause pluggIng of the reactor (due to viscous,
tarry by-products/ etc.) and temperatures higher than 250F.
may cause decomposition of the component(s) within the reaction
product.
Reaction Pressure; Improved petroleum recovery is
obtained when the pressure in the reaction zone is maintained
in the range of about 3 to about 50, preferably about 9 ~o about
35, and more pre~erably ~bout 15 to about 25 psia. At pressures
2~ ~re~ter than 5Q psia, the partial pressure o~ the gaseous SO3
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is generally too high to obtain a desired product, i.e., the
sulfonate is generall~ too hydrophilic for ef~icient oil recovery.
Also, at high pressures, large amounts of S03 diluent may be
neede~ to obtain a desired level of S03 partial pressure.
Contact Time: The contact time between the hydro-
carbon feedstock and SO3 contact time and the time the reaction
mixture enters the separator will generally be within the range
of about 0.01 to about 30 seconds, preferably about 0.1 to about
1~ seconds and more preferably from about .5 to about 5 seconds.
Reaction Apparatus: The preferred apparatus is a
continuous flow tubular reactor having an inlet for admitting
the hydrocarbon feedstock, plus any additive plus some recycle
reaction products, an inlet for the SO3 stream, and a vapor
inlet and an outlet. Streams should be in turbulent flow within
the reaction apparatus.
A Nash pump (e.g. Hytor vacuum pump, Nash Engineering
Co., Norwalk, Conn.~ is especially useful to compress the
effluent from the reaction zone and transfer the effluent to a
~apor liquid separator treferred to in the drawing as the reactor
2~ separator). The compressor or pump should be sufficient to obtain
a differential pressure of at least 0.01 psi and preferably at
least a~out 0.1 to about 20 psi. Also, the differential pre-
~sure s~ould be sufficient to cause the recycled vapor to enter
t~e reaction æone and to become substantially dispersed in the
~O3 vapor stream.
The reactor is preferably made of stainless steel but
any metal or nonometal having proper mechanical and corrosion-
resistant properties may be utilized.
29 Neutralization; The sulfonic acid is neutrali~ed
~/ -- 11 -
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'73
with a basic compound, e.g. sodium hydroxide, ammonia, a~noniurn
hydroxide, etc. Preferably, the basic compound is diluted
wtth water.
Extraction: ~ile not absolutely necessary to the
practice of the invention, it is preferred to extract at least
a portion (preferably paraffinic hydrocarbon) of the unreacted
hydrocarbons from the sulfonate product. To accomplish this,
the unextracted sulfonate mixture can be permitted to phase
separate at temperatures up to about 275F. and preferably
at about 125 to a~out 225 and more preferably about 150 to
a~out 200F. Add'tives such as alcohols, acids, salts, water,
etc. can be added to facilitate extraction of the petroleum
sulfonate. Examples of useful alcohols include those containing
l to about 5 carbon atoms, also semi-polar organic compounds such
as ~enzène are useful.
The amounts of unreacted hydrocarbon and salt contents
in the final petroleum sulfonate product can be controlled by
the operating conditions of the extraction process, the extraction
additive to unextracted sulfonate mix ratio and the extraction-
additive composition. For example, about 0.8 to about 2.0 lbs.,
~referably about 1.0 to about 1.8 lbs. and more preferably about
l.l to a~out 1.5 l~s. of a~ueous alcohol solution or water can
be admixed with each lb. o the unextracted sulfonate mix. A
preferred extraction additi~e composition is water containing
~bout 5~ to about 80% and more preferably about S5 to 75% by
weight of isopropanol--this composition is preferred where the
unextracted sulfonate mix contains about 15 weight percent
~ater.
~9 The mixture resultin~ after addition of the extraction
cb/ - 12
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additive will separate into either two or three phases; a
raffinate phase which consists primarily of unreacted hydro-
carbons, an extract phase which contains most of the petroleum
sulfonate produc~, and possibly (depending on the particulax
extraction solvent used) a brine phase which contains salts
and water.
The raffinate phase can be processed, e.g. by stripp-
ing, to recover any extraction additives and water from the
unreacted hydrocarbon. The extract phase can be fed to a
stripper to remove water and any lo~ boiling point additive
ro~ the petroleum sulfonate product. The brine phase, if any,
can be disposed of or can be further processed to recover salts,
e.~., ammonium sulfate which can be utilized as fertilizer.
The petroleum sulfonate is preferably filtered to
remo~e components which may tend to plug a subterranean
reseryoir. The pH of the sulfonate is preferably adjusted
to about 7 to about 10 before it is filtered.
Product Specification: The desired petroleum sul-
fonate product has an average equivalent weight within the range ;~
20 of about 350 to about 525, more preferably about 375 to about
475 and most preferabl~ about 390 to about 445. This average
equivalent weight range of the petroleum sulfonate is a major
quality control parameter and is directly related to th0 capabil-
ity o~ the petroleum 5ulfonate to impart micellar characteristics
to mixtures of hydrocarbon and aqueous medium. The equivalent
weight of the petroleum sulfonate is defined as the sulfonate
molecular weight diYided by the average number o sulfonate
gx~u~s per moleculeO It indicates the relative amount of mono-
29 sulonation and pol~sulonation, i.e., the equivalent weight
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becomes lower as the polysulfonation increase~.
Pre~aration of Micellar Dispersion S~stems
The micellar dispersion contains hydrocarbon, aqueous
medium, and petroleum sulfonate. Optionally, cosurfac~ant and/or
electrolyte can be incorporated. Examples of volume amounts
include about 2% to about 90~ hydrocarbon, about 5~ to about
q5~ a~ueous medium, about 4% to about 25% or more of the petroleum
sulfonates ¢can be 50% active sulfonate), about 0.01 to about
20~ cosurfactant, and about 0.001 to about 5% (weight % based on
aqueous medium) of electrolyte ~can be sulfite and/or bisulfites
from the excess SO2 sulfates, etc.). The micellar dispersions
can be oil-external or water-external.
The hydrocarbon of the micellar dispersion can be crude
oil or partially refined fraction of crude oil, or refined
fractions of crude oil, or synthetic hydrocarbons (including
halohydrogenated hydrocarbons)O The aqueous medium can be
~oft or hard water containing minor amounts of salts, or brack-
ish Water. The cosurfactant can be an amine, aldehyde, ketone,
~ydroxy-containing compound ~including conventional alcohols
2~ and ethoxylated alcohols), ester, ether, mixtures thereof, etc.,
containin~ 1 to about 20 or more carbon atoms. Numerous electro-
lytes are useful, preferably they are inorganic acids, inorganic
bases, and inor~anic salts. Examples of patents which teach
the u~e of particular components useful in micellar dispersions
include those defined l~n the prior art as well as others known
~n the art.
Tha micellar dispersion can optionally be composed of
28 two or more different petroleum sulfonates.
~b/ - 14 -
73
EX~MPLES
.. . .
The following Examples are intended to more ~ully
illustrate the invention and are not ko be considered as
limitin~ the inyention in any way. Each o~ the Examples
utilize the apparatus shown in khe drawin~. The process
conditions are defined in the Examples.
Each of the sul~onates produced in Examples I and II
i~ utilized to produce a micellar dispersion ha~ing the com-
position giyen in Table A. A certain number of pore volumes
~indicated under the respecti~e example) of the resulting
micellar dispersion is injected into a 6" diameter core disc
Ctaken from the Henry Reservoir, Crawford County, Illinois,
U.S.A.). The core disc is prepared by first saturating it
~ith ~ater, then flooding oil therethrough, e.~., North Crawford
Count~ ! S pipeline crude oil, Illinois Basic crude oil, to
xesidual water Cthat is, until no more water is displaced from
t~e coreL~ then Water flooded to residual oil ~that is until
no additional oil is displ~ced from the core) using a simulated
connate water. The water-flooded core disc at this point
~simulate$ an oil fleld a~ter conventional water flooding. A
slug ~the percent pore yolume is indicated under the respectlve
exa~plel i~ then injected into the core to displace residual oil.
Injection of the micellar dispersion is followed by injection of
lO~ PV (pore volume) of water containing llO0 ppm of Dow 700
pusher polymer (a partially hydrolyzed, high molecular weight
polyacrylamide, Dow Chemical Co., Midland, Michigan) followed
~y 53% PV of water containing 615 ppm of Dow 700 Pusher polymer
and this in turn followed by water containing 117 ppm of the
2~ pusher polymer - the water used is a simulated connate water.
cb/ - 15 -
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The "oil recovery" is calculated as the volume percent of the
residual oil in place after water flooding.
EXA~PLE I
Hydrocarbon Feedstock:
Type = Illinois Basin Crude Oil (Crawford County,
Illinois, U.S.A.) 36 API @ 60F.
Rate = 1000 lbs. per hour
H2O content = 800 to 2000 ppm H20
Reaction Conditions:
Type = Back mix tubular reactor ~ith liquid
xecycle for temperature control and vapor
recycle for SO3 dilution
Liquid Recycle ratio = 4900 lbs./hr (i.e. 4.9 lbs.
per lb. Crude Oil)~cooled from 181F. to 162F.
in cooler)
Temperature = 181~
Pressure = 18.8 p,s.i.a,
SO3 Conditions:
~ ate = 100 lbs/~our
Temperature of SO3 Feed = 268F~
Pressuxe = 28 p~s.i.a~
~O3 Diluent Conditions:
T~pe ' ~2 and li~ht h~drocarbons flashed from reactor
e~luent
Temperature ~ 179F.
~reSsure - 2005 p.~.i,a.
Rate ~ 270 lbs per hour ~i.e. 3.27 mole~/mole SO3)
cb/ - 16 -
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Composition = 51.9% SO2, 38.3~ Cl~C7 hydroc~rbon,
9.8% N2 from instrument pur~iny, average molecular
weight ~ about 66
SO3 Partial Pressure in reaction zone - 4.4 p.s.i.a.
Sulfonation Additive:
T~pe - None
Neutralization Conditions:
Reactor type = back mix ~low reactor ~2 sta~e mixer)
Temperature = 162F.
~xessure = 45 p.s.i.a.
NH3 Rate = 26.5 lbs~hr.
~ater Rate _ 980 lbs!hr
Phase Separation Conditions and Output:
Neutrallzation p~ = 5.5 - 6.5
Temperature = 162F.
Pressure = 13.1 p.s.i.a.
Time = 3.7 hours residence time in continuous settler
Unreacted Elydrocarbon Rate = 604 lb/hr.
$ul~onate/5alt/Water Rate = 1455 lbs/hr.
~2 ~crubber Conditions:
Water Rate = 133 lbs/hr @ 132F.
NH3 Rate = 3 lbs/hr
Brine (ef~luent, contains sulfite, etc.) Rate =
- 136 lbs/hr @ 155F.
Brine Compo~ition = 13.5 wt % salt reported as ~NH4~2SO4
Scrubber vent ~hydrocarbon vented) = about 10 lbs/hr.
(no hydrocarbon vent absorber Wa5 used)
Micellar Solution ~efore ammonia or cosurfactant addition);
29 Rate = 1585 lbs/hr
cb/ - 17 -
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~7~37~
Composition = 3.82 wt % ~ SO3NH4
4.61 wt ~ salt reported as ~NH4)2SO4
69.0 wt ~ ~I2O
This micellar soluti.on was diluted with wa-ter to
obtain the composition yiven in Table A. Also a
cosurfactant was added
Sulfonate Yield = 256 lbs/hr ~416 Eq. wt) ~.26 lbs/lb
crude oil)
Oil Recoyery = 58.2 vol % and 54.5 vol % of residual oil
after water flooding using 6" Henry Disc
cores from Crawford County~ Illinois,
usin~ a 7% PV of micellar solution des-
cribed in Table A followed by a 10% PV of
1100 ppm Dow 700 followed by 53% PV of 615
ppm Dow 700 followed by 117 ppm Dow 700
rollowed by Henry plant water.
EXAMPLE II
Hydrocarbon Feedstock:
Type = Illinois Basin Crude Oil ~Crawford County,
Illinois, U.S.A.) 36 API @ 60F.
Rate = 750 lbs per hour ~1070 ppm H2O)
Reaction Conditions:
Type = Back mlx tubular reactor with liquid recycle
for temperature control and vapor recycle or
SO3 dilution.
Liquid Recycle ratio = 5600 lbs/hour (7.43 lbs per lb Crude)
(cooled from 181Fo to 168F~ in cooler)
Temperature = 181F.
Pressure = 18.0 p.s.i.a.
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SO3 Conditions:
Rate = 59.5 lbs/hour
Temperature of SO3 feed = 275F.
Pressure = 22.7 p.s.i.a.
Reaction Solvent Conditions:
Type = Llone
SO3 Diluent Conditions:
Type = SO2 and light hydrocarbons from reactor effluent
Temperature = 175F.
` 10 Pressure = 20.6 p.s.i.a.
Rate = 360 lbs/hour ~i.e. 7.3 moles/mole SO3)
Composition - 66 average molecular weight
SO3 Partial Fressure in Reaction Zone - 2.2 p.s.i.a.
Sulfonation Addit~ve:
Type = None
Neutralization Conditions:
Reactor Type = back mix ,~low reactor ~2 stage mixer)
Temperature - 152F.
~ressure = 47 p.s.i.a.
NH3 Rate = 14.7 lbs~hour
~ater Rate = 690 lbs/hour
Neutrali~at~on pH = 5~
Phase Separation Conditions and Results:
Temperature = 154F.
Pressure = 13.1 p.s.i.a.
Time = 12 hours residence time
Unreacted Hydrocarbon Rate = 466 lb/hr
Sulfonate~alt/EI2O Rate = 1010 lbs/hr.
29 ~2 Scrubber Conditions:
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Water Rate = 85.0 lb/hr @ 128F.
NH3 Rate = 2,0 lbs/hr
Brine Rate = 87.2 lbs/hr @ 128F.
Brine Composition - 14.82 wt ~ salt reported as
~H4)2S04
Hydrocarbon vented from scrubber = about 7 lbs/hour
(No hydrocarbon yent absorber was used.~
Micellar Solution ~before ammonia or cosurfactant addition):
Rate = lQ97 lbs~hour
Com~osition = 3.38 wt ~ -S03NH4
4.21 Wt % salt reported as (~H4~2S04
68.1 ~t % H20
(NH4~2S04 was added to the sulfonate/salt/water solution
instead of the brine to keep the ~03NH4 concentration
at 3.38 wt %)
Sulfonate Yield = 147 lbs/hr. ~416 average Eq. wt)
0.20 lbs/lb crude oil
Oil Recover~ = 7~74 % PV recovers 70.5 vol ~ and 70.3
vol % in two separate runs, and 7~ PV
recovers 52.3 vol % in a third run.
The ~ame polymer u~sed in Example I is
- used ~n each of these ~loods.
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TABLE A
MICELLAR DISPERSION COMPOSITIONS
.. .
Wt %
Sulfonate
Product-In Cosurfactant
Example No. S03NH4 Salt Type Wt % Water Balance
lS the
I 3.5 4.4 primary 1.0 71.7 organic
amyl
alcohol portion
II 3.4 4.2 primary 1.0 68.1 of the
amyl sulfonate
alcohol plus
- crude oil
It should be understood that the invention is capable
of a variety of modifications and variations which will be
made apparent to those skilled in the art by a reading of the
specification and which are to be included within the spirit
of the claims appended hereto.
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