CA1295118C - Steam foam process - Google Patents
Steam foam processInfo
- Publication number
- CA1295118C CA1295118C CA000546987A CA546987A CA1295118C CA 1295118 C CA1295118 C CA 1295118C CA 000546987 A CA000546987 A CA 000546987A CA 546987 A CA546987 A CA 546987A CA 1295118 C CA1295118 C CA 1295118C
- Authority
- CA
- Canada
- Prior art keywords
- steam
- foam
- reservoir
- oil
- surfactant
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
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Classifications
-
- C—CHEMISTRY; METALLURGY
- C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
- C09K—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
- C09K8/00—Compositions for drilling of boreholes or wells; Compositions for treating boreholes or wells, e.g. for completion or for remedial operations
- C09K8/58—Compositions for enhanced recovery methods for obtaining hydrocarbons, i.e. for improving the mobility of the oil, e.g. displacing fluids
- C09K8/594—Compositions used in combination with injected gas, e.g. CO2 orcarbonated gas
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- E—FIXED CONSTRUCTIONS
- E21—EARTH DRILLING; MINING
- E21B—EARTH DRILLING, e.g. DEEP DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
- E21B43/00—Methods or apparatus for obtaining oil, gas, water, soluble or meltable materials or a slurry of minerals from wells
- E21B43/16—Enhanced recovery methods for obtaining hydrocarbons
- E21B43/24—Enhanced recovery methods for obtaining hydrocarbons using heat, e.g. steam injection
Abstract
A B S T R A C T
STEAM FOAM PROCESS
A steam foam process for displacing oil within a subterranean reservoir is improved by injecting into the reservoir a steam-foam forming mixture of steam and a C11-C20-di-alkylarenesulphonate surfactant.
STEAM FOAM PROCESS
A steam foam process for displacing oil within a subterranean reservoir is improved by injecting into the reservoir a steam-foam forming mixture of steam and a C11-C20-di-alkylarenesulphonate surfactant.
Description
STEAM FOAM PE~OCESS
The invention rela~es eo a steam foam process for producing oil from, or displacing oil within, a subterranean reservoir.
In this process steam is in~ected into, and fluid ls produced from, horizontally spaced locations within a portion of an oil reservoir in which the disposition of a steam flow path i6 de-termined by gravity and/or oil distribution. After a steam channel has been formed the composition of the fluid being injected is changed from seeam to a steam-foam-forming mixturs by addition of surfactant components. The composition of the mixture is correlated with the properties oE the rocks and the fluids in the reservoir so that the pressure required to in~ect the mlxture and to move it through the steam channel exceeds that required for steam alone but is less than the reservoir fracturing pressureO
The composition and rate of in~ecting the mixture is subsequently adjusted to the extent required to maintain a flow of steam foam within the channel at a relatively high pressure gradient at which the oil-displacing and channel-expanding effects are significantly greater than those provided by the steam alone. Oil is recovered from the fluid produced from the reservoir.
The present invention also relates to an improvement in an oil recovery process in which steam is cyclically in~ected into and fluid i8 backflowed from a heavy oil reservoir which is susceptible to a gravity overrlde that causes an oil layer to become ad~acent to a gas or vapour-containing sub~tantially oil-de6aturated zone in which there is an undesirable intake and retention oE the inJected fluid within the desaturated zone. In such a process, the fluid being in~ected is changed from steam to a steam-foam-forming mixture by addition of surfactant components arranged to form a steam foam within the reservolr having physical and chemical properties such that it (a) is capable of being iDJected into the reservoir without plugging any portion of the reservoir at a pressure whlch exceeds that required for in~ecting steam but ls less than the reservolr fracturing pressure and (b) is chemieally weakened by contact with the reservoir oil so that i~ i6 more mobile ln sand containing that oil than in sand which is substantially free of that oil. The surfactant-conta:lnlng steam is in~ected into che reservoir at a rate 810w enough to be conducive to displacing a front of the steam foam along the oil-containing edge portions of the oil-desaturated zons than along the central portion of that zone. And, fluid is backflo~ed from the reservoir at a time at which part or all of the steam is condensed within the steam foam in the reservoir.
As used herein the following terms have the following meanings: "steam foam" refers to a foam i.e. gas-liquid dlspersion which (a) is capable of both reducing the effective mobility, or ease with which such a foam or dispersion will flow within a permeable porous medium and (b) has steam in the gas phase thereof. "Mobility" or "permeability" refers to an effective mobility or ease of flow of a foam within a permeable porous medium. A "permeability reductionl' or "mobility reduction" refers to reducing the ease of such a foam flow due to an increase in the effective viscosity of the fluid and/or a decrease in the effec tive permeability of the porous medium. A reduction in ~uch a mobility or permeability can be detected and/or determined by measuring differences in internal pressures within a column of ~5 permeable porous material during a steady state flow of fluid through a column of such material. "Steam quality" as used re-garding any steam-containing fluid refers to the weight percent of the water in that Eluid which is in the vapour phase of the fluid at the boiling temperature of that water ae the pressure of the fluid. For example: in a monocomponent steam-containing fluid which consists entirely of water and has a steam quulity of 50~, one-half of the weight of the water is in the vapour phase; and, ln a multicomponent steam-containing fluid which contains nitrogen in the vapour phase and dissolved or dispersed surfactant and electrolyte in the liquid phase and has a steam quality of 50~, ~3~
one-half the welght of the weight of the water in the multi-component steam-containing fluid ls ln the vapour phase. Thus, the steam quality of a steam-containing fluid can be calculated as, for example, 100 times ~he m~ss (or mass flow rate) of the wAter vapour in that fluid div-lded by the sum of the mass (or mass Elow rate) of both the water vapour and the liquid water in ~hat fluid.
"Steam-foam-forming mixture" (or composition) refers to a mixture of steam and aqueous liquid solution (or dispersion) of surfactant, with some or all, of the steam being present in the gas phase of a steam foam. The gas phase may ~nclude non-condensable gas(es) such as nitrogen.
Object of the invention is an improved process for displacing oil within an oil-containing subterranean reservoir by flowing a steam-containing fluid in con~unction with a surfactant component through a relatively steam permeable zone within said reservoir.
According to the invention the surfactant component comprises in substantial part at least one sulphonate of the formula RS03X
in which R is di-alkylaryl including aryl is phenyl, toluyl or xylyl having attached thereto two linear alkyl groups with equal or different chain length, but each containing 11-20 carbon atoms in the alkyl chain and X is sodium, potassium, lithium or ammonium. Such ~ulphonates will be further on denoted as Cll-C20-dialkylarenesulphonates.
The di-alkylarenesulphonate-containing steam-foam-forming mixture suitably includes an aqueous solution of electrolyte and advantageously further also includes a substantially noncondens-able gas, with each of the surfactant, electrolyte and gas com-ponents being present in proportions effective for steam-foam-formation in the presence of the reservoir oil. The invention also relates to the di-alkylarenesulphonate-contalning steam-foam-forming mi~tures which are described herein.
The invention is uaeful where it is desirable to remove oil from, or displace oil within, a subterranean reservoir. For example, the invention can be used to move oil or an emulsion of oil and water away from a well borehole in a well-cleaning type of operation, and/or to dlsplace oil into a producing location in an oil-recovery operation.
In particular, the present invention re]ates to a process for recoverlng oil from a subterranean reservoir, comprising:
injecting steam and producing fluid at horizontally spaced locations withln a portion of an oil reservoir in which the disposition of a seeam flow path is determined by the effect o~
gravity and/or oil distribution, rather than b~ing substantially confined wi~hin at least the one most permeable layer of reservoir rocks;
advantageously malntaining raees of steam in;ecting and fluid production such that a steam channel has been extended from the injection location;
changing the composition of the fluid being injected from steam to a steam-foam-forming mixture by addition of a linear Cll-C20-di-alkylarenesulphonate-containing compound, whilst continuing to produce fluid from the reservoir;
correlating the composition of the steam-foam-formlng mixture with the properties of the rocks and fluids in the reservoir so that the pressure required to in~ect the mixture and the foam it forms or comprises into and through the steam channel exceeds that required for steam alone but is less than the reservoir fracturing pressure; and ad~usting the composition of the fluid being in~ected into the steam channel to the extent required to maintain a flow of both steam and foam within the channel in response to a relatively high pressure gradlent at which the oil displacing and channel expanding effects are slgnificantly greater ehan those provided by steam alone, without plugging the channel.
The inventlon al~o relates to an oil recovery process in which steam is cyclically in~ected into and fluid is backflowed from a subterranean heavy oil reservolr which is susceptible to gravity override and tends to intake and retain undesirably large proportions of the in~ected fluid. This process comprises:
~5~
in~ecting steam mixed with a linear Cll-C20-di-alkylarene-sulphonate-containing steam-foam-forming compound which is arranged for forming a steam foam which (a) can be displaced through the pores of the reservoir, withoue plugging any port-lon of the reservoir 9 in response to a pressure ~hich exceeds that required for displacing steam through the reservo~r but i8 less than the fracturing pressure of the reservoir, and (b) can be weakened by contact wi~h the reservoir oil to an extent such that the weakened foam is significantly more mobile in reservoir oil-containing pores of a porous medium than in oil-free pores of that medium;
injecting the steam-foam-forming mixture at a rate equivalent to one which is slow enough to cause the foam formed by that mixture to advance more rapidly through the pores of a reservoir lS oil-containing permeable medium than through the pores of a substantially oil-free permeable medium; and backflowing fluid from the reservoir after a steam soak time sufficient to condense part or all of the steam in the in~ected steam-foam-forming mixture. The steam-foam-forming mixture preferably comprises steam, a noncondensable gas, a linear Cll-C20-di-alkylarenesulphonate surfactant and an electrolyte.
The invention provides unobvious and beneficial advantages in oil displacement procedures by the use of the di-alkylarene-sulphonate surfactant in the steam-foam-forming composi~ions. For example, where a steam-foam-forming mixture contains such a surfactant and an electrolyte in proportions near optimum for foam formation, the present surfactant components provide exceptionally strong steam foams having mobllities many times less than those of steam foams using other surfactants. In nddition, significant reductions are reached in the mobilities of the steam foams at concentrations which are much less than those required for equal mobility reductions by the 3urfactants which were previously considered to be the befit available for such a purpose. The use of the present di-alkylarenesulphonate surfactant components involves no problems with respect to thermal and hydrolytic stability. ~o ~.2~
chemlcal or physical deterioration has been detectable in the presen~ alkylarenesulphonate surfactants that were recovered along with the fluids produced during productions of oil from subterranean reservoirs. In each of those types of sulphonate surfac~ants the sulphur atoms of the sulphonate groups are bonded directly to carbon atoms. The surfactants which were recovered and tested during the production of oil had travelled through the r~servoirs at steam tempera~ures for significant times and distances.
The present Cl1-C20-di-alkylarenesulphonate-containing steam foams have been found to represent a substantial improvement in mobility reduction over foams based on the mono-alkylaryl sulphonates e.g., dodecylbenzene sulphonates. The foams to be used according to the present invention represent also substantial improvement over the C16-C18 alpha-olefinsulphonate-containing foams.
The present invention further relates to compositions con-taining at least one C11-C20-di-alkylarenesulphonate, and steam, optionally electrolyte, and optionally noncondensable gas, that are suitable for use in oil-displacing and/or producing processes.
Of particular interest in this respect are steam-foam-forming compositions consisting essentially of (a~ water, which ls present in the composition, at a temperatùre substantially equalling its boiling temperature, at the pressure of the composi~ion, in both a liquid phase and a vapour phase; (b) a surfactant component present in the liquid phase of the composition in an amount between O.a1 and 10 percent by ~eight, calculated on the weight of the liquid phase, said surfactant component comprising in 8ub-stantial part at least one C11-C20-dl-alkylarenesulphonate; (c) an electrolyte present in the liquid phase of the composition in an amount between 0.001 percent by welght (calculated on the weight of the liquid phase) and an amount tending to partition the surfactant into a aeparate liquid phase; and (d) a noncondensable gas present in the vapour phase in an amount between about 0.0001 and 0.3 percent by mol, calculated on total mols in the vapour phase.
Illustrative of the di-alkylarenesulphonate surfactant~
suitably employed in steam-foam drive processes of enhanced performance, according to the invention, are the di-alkylarene-sulphonates obtalned by reacting a linear Cll-C20-di-alkylbenzene linear Cll-C20-di-alkyltoluene and/or linear Cll-C20-di-alkylxylene with sulphur trioxide followed by neutralization of the sulphonic acid. Particularly suitable for purposes oE the invention is a sulphonate derived from substantially linear 10 Cll-C20-di-alkyl-benzene.
Different reservoir materials have different debilitating effects on the strength of a steam foam. Tests should there-fore be carried out to determine the sulphonates or sulphonate-containing steam-foam-forming compositions that perform optimally in a given reservoir. This is preferably done by testing the influence of specific sulphonates on the mobility of a steam-containing fluid having the steam quality selected for use in the reservoir in the presence of the reservoir material.
Such tests are preferably conducted by flowing steam-contain-ing fluids through a sand pack. The permeability of the sand packand foam-debilitating properties of the oil in the sand pack should be at least substantially equivalent to those of the reservoir to be treated. Comparisons are made oE the mobility of the steam-containing fluid with and without the surfactant component.
The mobility is indicated by the substantially steady-state pressure drop between a pair of points located between the inlet and outlet portions of the sand pack in positions which are sub staneially free of end effects on ehe pressures.
Some laboratory tests to determine steam mobility will now be described with reference to Figures 1 and 2.
Figure 1 shows schematically a sand pack test apparatus which can be made of currently avnilable apparatus components. The apparatus consists of a cylindrical tube 1 that is ~00 mm long and has a cross-sectional area of 8 cm2. Such a tube is preferably arranged for a horizontal flow of fluid from an inlet 2 to an 3~
outlet 3. The tube is preferably provided with 5 pressure taps 4, 5, 6, 7 and 8. The location of the first pressure tap 4 is at a distance of 150 ~m from the inlet 2. The locations of the other taps are chosen so as to divide the part of the tube 1 situated behind tap 4 into equal parts of 50 mm. The tube l contains a permeable and porous column of sultable material, such as a sand pack, which is capable of providing an adequately reallstic laboratory model of a subterranean reservoir.
At the inlet end 2, the sand pack or equivalent column of permeable material is arranged to receive separate s$reams of steam, noncondensable gas such as nitrogen, and one or more aqueous liquid solutions or dispersions containing a surfactant to be tested and/or a dissolved or dispersed electrolyte. Some or all of those components are in~ected at constant mass flow rates proportioned so that steam of a selected quality, or a selected steam-containing fluid or composition, or a steam-foam-forming mixture of a selected steam quality can be injected and will be substantially homogeneous substantially as soon as it enters the face of the sand pack.
In the tests, steam-foam-forming mixtures are compared with and without surfactant components added thereto, by measuring pressure gradients formed within a sand pack during flows through the pack at the same substantially constant mass flow rate.
Numerous tests have been made of different steam-foam-forming mixtures using sand packs composed of a reservoir sand and having a high permeability, such as 10 darcys. The pressures were measured with pressure detectors (not shown) (such as piezoelectric devices) installed at the inlet 2 and at the taps 4, 5, 6, 7 and 8 of the tube 1. The results of such tests have proven to be generally comparable with the results obtained in the field.
In the laboratory tests, the steam-foam-forming components were in~ected at constant mass rates until substantially steady-state pressures were obtained at the lnlet and at the taps. The ratio between the steady-state pressures at the taps during flow of steam mixed with the foam-forming surfactant component and the steady-state pressure at the taps during flow of the steam by itself are indicative for the mobility reduction. The higher this ratio, ~he stronger ehe steam foam and the higher the mobllity reduction caused by the steam-foam forming mixture.
Figure 2 illustrates the results of comparaeive tests with steam and various steam-foam-forming mixtures in sand packs containing Oude Pekela Reservoir sand having a permeability of 7 darcys. The backpressure was 21 bar, corresponding with a tem-perature of 215 C. The steam injection rate was 600 cm9/min, having in the water phase containing 0.5 %w sodium C8-C10-di-alkylbenzenesulphonate. The figure shows the ~ariation of the pressure difference in bar (~-axis) with distance in centimetres (X-axis) from the pack inlet 2. The pressures were measured at the inlet 2, at the taps 4, 5, 6, 7 and 8, and at the outlet 3 of the pipe 1 of Figure 1. Curve A relates to the displacement wherein a mixture of 85% quality steam, having in the water phase containing 0.5 %w sodium C8-C10-di-alkylbenzene-sulphonate, was used as a displacing composition.
Curve B relates to using a steam-containing fluid having a steam quality of 85% and a water phase which contains 0.5% by weight of a surfactant. In the Curve B test, the surfactant was a linear sodium Cll-C12-di-alkylbenzenesulphonate.
Curve C relates to using the mixture used for Curve B except that the surfactant was a linear sodium C13-Cl~-di-alkylbenzene-sulphonate.
To all surfactant solutions 0.25 /Ow sodium Cl~ C16 a-olefin sulphonste had been added ln order to merease the solubility of the sodlum di-alkylbenzenesulphonates.
The greatly improved steam permeability reduction performance of the presently described C11-C20-di-alkylarenesulphonate-containing surfactant component i9 clear from the Curves B and C
as compared to the Curve A in Figure 2.
Composition6 and procedures suitable for use in the present invention For purposes of the present invention, the surfactant component of the steam-foam-forming mixture is necessarily comprised in substantial part o linear Cll-C20-di-alkylarenesulphonate.
Mat~rials of this class but with a much shorter alkyl chain have heretofore found commercial utility, for example, in detergent formulations for industrial, household and personal care application.
A class of di-alkylarenesulphonates very suitable for use in the present invention is that derived from a particular class of olefins, which may be defined for present purposeR in terms of the configuration and number of carbon atoms in their molecular struceure. These olefins preferably have a carbon number of 13-14.
In terms of molecular structure, these olefins are aliphatic and mainly linear. Either alpha- or internal olefins are considered suitable for the alkylation route chosen to produce the products to be used according to the invention. For purposes of derivation of the di-alkylarenesulphonates for use in the process according to the invention, olefins are advantageously applied in which at least 90% of the molecules are alpha-olefins.
Particularly attractive are sulphonates derived from the SHOP alpha-olefins (trademark) sold by Shell Chemical UK, in part for their linear structure and high alpha-olefin content, i.e , greater than 95% in each case. The SHOP alpha-olefins are prepared by ethylene oligomerization. Products having a high content of internal Cll-C20-olefins are also commercially manufactured, for instance, by the chlorination-dehydrochlorination of paraffins or by paraffin dehydrogenation, and can also be prepared by isomerization of alpha-olefins. Internal~olefin-rich products are mamlfactured and sold, for example, by Shell Chemical UK.
For preparation of di-alkylarenesulphonates, the olefins as described above are subJected to reaction wlth benzene, toluene or xylene. The di-allcylbenzene, di-alkyltoluene or di-alkylxylene isomers are reacted with sulphur trioxide. The term "sulphur trioxide" as used in the present specification and clalms is intended to include any compounds or complexes which contain or yLeld S03 for a sulphonatlon reaction as well as S03 per se. This reaction may be conducted according to methods well known in the chemical arts, typically by contact of a flow of dllute S03 vapour with a thin film of liquid alkylate at a temperature in the range of about 5 to 50~C. The reac~ion between the S03 and the alkylate yields a sulphonlc acid which is neutralized by reaction with a base, preferably an alkali metal hydroxide3 oxide, or carbonate.
The specific composition of di-alkylarenesulphonates prepared as described above (and also, for instance, the ~ethods used for sulphonation, hydrolysis, and neutralization of the specified olefins) have not been found to be a critical factor to the performance of the surfactant in the steam foam process according to this in~ention. In this regard, it is observed that factors which have conventionally governed the choice of sulphonation conditions, e.g., product colour, clarity, odour, etc., do not carry the same weight in the preparation of di-alkylarene-sulphonates for purposes of use in the process according to the invention that they have been accorded in detergent manufacture.
Consequently, reaction conditions outside of those heretofore considered desirable for alkylate sulphonation are still suitably applied in the preparation of surfactant components suitable for use in the steam-foam-forming mixture.
For purposes related to maintaining product stability, conventional manufacture typically yields a dilute solution or dispersion of the di-allcylarenesulphonates, for instance, products with a 15-30 Y~wt actlve matter content ln water. Such products may be directly applied to the preparation of steam-foam forming mixtures for purposes of this invention.
Suitable alkylarenesulphonates, generally prepared by methods such as descrlbed above, are themselves commercially available products.
The stren8th of the foam formed by the steam-foam-forming composltion including dl-alkylarenesulphonate tends to increase with increases in the proportion of the surfactant and/or electrolyte components of the composition. Also, there tends to be an optimum ratio of surfactant and electrolyte components at which the surface activity of the composition is maximized.
The steam-foam-forming composition according to the present ~nvention can Eorm a seeam-foam capable of reducing the effective mobility of the steam to less than about l/lOth and even to 1150th-1175th of the mobility it would have within a permeable porous medi~m in the absence of t~e surfactant.
The steam used in the present process andlor compositions can be generated and supplied in the form of substantially any dry, wet9 superheated, or low grade steam in which the steam condensate andjor liquid components are compa~ible with, and do not inhlbit9 the foam forming properties of the foam~forming components of a steam-foam-forming mixture according to the present invention. The steam quality of the steam as generated andlor amount of aqueous liquid with which it is mixed be such that the steam quality of the resulting mixture is preferably from 10 to 90%. The desired steam-foam is advantageously prepared by mixing the steam with aqueous solution(s) of the surfactant component and optionally, an electrolyte. The water content of these aqueous solutions muse~ of course, be taken into account in determining the steam quality of the mixture being formed.
Suitably, the noncondensable gas advantageously used in a steam-foam-forming mixture according to the present invention can comprise substantially any gas which (a) undergoes little or no condensation at the temperatures (100-350 C) and pressures (1-100 bar) at which the steam-foam-forming mixture is preferably injected into and displaced through the reservoir to be treated and (b) is substantially inert to and compatible with the foam-forming surfactant and other components of that mixture. Such a gas is preferably nltrogen but can comprlse other substantlally lnert gases, such as air, ethane, methane, flue gas, fuel gas, or the like. Suitable concentrations of noncondensable gas in the steam-foam mixture fall in the range of from 0.0001 to 0.3 mole percent ~uch as 0.001 and 0.2 mole percent, or between 0.003 and 0.1 mole percent of the gas phase of the mixture.
Suitably, the electrolyte used should have a composition similar to and should be used in a proporeion similar to those described as suitable alkali metal salt electrolytes in the above-mentioned US~ patent speciflcation 4,086,964. An aqueous solution may be applied that contain~s an amount of electrolyte substantially equivalent in salting-out effect to a sodium chloride concentration of from O.OOl to 10% (but less than enough to cause significant salting out) of the liquid-phase of the steam. Some or all of the electrolyte can comprise an inorganic salt, sush as an alkali metal salt, an al~ali metal halide, and sodiutn chloride.
Other inorganic salts, for example, halides, sulphonates, carbonates, nitrates and phosphates, in the form of salts of alkaline earth metals, can be used.
Generally stated, an electrolyte concentration may be applied which has approximately the same effecs on mobility reduction of the foam as does a sodium chloride concentration of between O.OOl and 5 percent by weight (but less than a salting out-inducing proportion) of the liquid phase of the steam-foam-forming mixture.
The electrolyte concentration may be between O.OOl and 10 percent calculated on the same basis.
In compounding a steam-foam-forming mixture or composition in accordance with the present invention, the steam can be generated by means of substantially any of the commercially available devices and techniques for steam generation. A stream of the steam being ln~ected lnto a reservoir is preferably generated and mixed, in substantlally any surface or downhole location, with selected proportions of substantially noncondensable gas, aqueous electrolyte solution, and foam-formlng surfactant. For example, in such a mixture, the quality of the steam which is generated and the concentration of the electrolyte and surfactant-containing aqueous liquid wlth which it is mlxed are preferably arranged so that (l) the proportion of aqueous liquid mixed with the dry steam which i9 in~ected into the reservoir is sufficient to provide a steam-containing fluid having a steam quality of from 10-90% (preferably from 30-85~); (2) the weight proportion of surfactant dissolved or dispersed in the aqueous liquid ls from O.Ol to lO.O (preferably from 1.0 to 4.0); and (3) the amount of noncondensable gas is from 0.0003 to 0.3 mole fraction of the gas phase o the mixture.
The invention rela~es eo a steam foam process for producing oil from, or displacing oil within, a subterranean reservoir.
In this process steam is in~ected into, and fluid ls produced from, horizontally spaced locations within a portion of an oil reservoir in which the disposition of a steam flow path i6 de-termined by gravity and/or oil distribution. After a steam channel has been formed the composition of the fluid being injected is changed from seeam to a steam-foam-forming mixturs by addition of surfactant components. The composition of the mixture is correlated with the properties oE the rocks and the fluids in the reservoir so that the pressure required to in~ect the mlxture and to move it through the steam channel exceeds that required for steam alone but is less than the reservoir fracturing pressureO
The composition and rate of in~ecting the mixture is subsequently adjusted to the extent required to maintain a flow of steam foam within the channel at a relatively high pressure gradient at which the oil-displacing and channel-expanding effects are significantly greater than those provided by the steam alone. Oil is recovered from the fluid produced from the reservoir.
The present invention also relates to an improvement in an oil recovery process in which steam is cyclically in~ected into and fluid i8 backflowed from a heavy oil reservoir which is susceptible to a gravity overrlde that causes an oil layer to become ad~acent to a gas or vapour-containing sub~tantially oil-de6aturated zone in which there is an undesirable intake and retention oE the inJected fluid within the desaturated zone. In such a process, the fluid being in~ected is changed from steam to a steam-foam-forming mixture by addition of surfactant components arranged to form a steam foam within the reservolr having physical and chemical properties such that it (a) is capable of being iDJected into the reservoir without plugging any portion of the reservoir at a pressure whlch exceeds that required for in~ecting steam but ls less than the reservolr fracturing pressure and (b) is chemieally weakened by contact with the reservoir oil so that i~ i6 more mobile ln sand containing that oil than in sand which is substantially free of that oil. The surfactant-conta:lnlng steam is in~ected into che reservoir at a rate 810w enough to be conducive to displacing a front of the steam foam along the oil-containing edge portions of the oil-desaturated zons than along the central portion of that zone. And, fluid is backflo~ed from the reservoir at a time at which part or all of the steam is condensed within the steam foam in the reservoir.
As used herein the following terms have the following meanings: "steam foam" refers to a foam i.e. gas-liquid dlspersion which (a) is capable of both reducing the effective mobility, or ease with which such a foam or dispersion will flow within a permeable porous medium and (b) has steam in the gas phase thereof. "Mobility" or "permeability" refers to an effective mobility or ease of flow of a foam within a permeable porous medium. A "permeability reductionl' or "mobility reduction" refers to reducing the ease of such a foam flow due to an increase in the effective viscosity of the fluid and/or a decrease in the effec tive permeability of the porous medium. A reduction in ~uch a mobility or permeability can be detected and/or determined by measuring differences in internal pressures within a column of ~5 permeable porous material during a steady state flow of fluid through a column of such material. "Steam quality" as used re-garding any steam-containing fluid refers to the weight percent of the water in that Eluid which is in the vapour phase of the fluid at the boiling temperature of that water ae the pressure of the fluid. For example: in a monocomponent steam-containing fluid which consists entirely of water and has a steam quulity of 50~, one-half of the weight of the water is in the vapour phase; and, ln a multicomponent steam-containing fluid which contains nitrogen in the vapour phase and dissolved or dispersed surfactant and electrolyte in the liquid phase and has a steam quality of 50~, ~3~
one-half the welght of the weight of the water in the multi-component steam-containing fluid ls ln the vapour phase. Thus, the steam quality of a steam-containing fluid can be calculated as, for example, 100 times ~he m~ss (or mass flow rate) of the wAter vapour in that fluid div-lded by the sum of the mass (or mass Elow rate) of both the water vapour and the liquid water in ~hat fluid.
"Steam-foam-forming mixture" (or composition) refers to a mixture of steam and aqueous liquid solution (or dispersion) of surfactant, with some or all, of the steam being present in the gas phase of a steam foam. The gas phase may ~nclude non-condensable gas(es) such as nitrogen.
Object of the invention is an improved process for displacing oil within an oil-containing subterranean reservoir by flowing a steam-containing fluid in con~unction with a surfactant component through a relatively steam permeable zone within said reservoir.
According to the invention the surfactant component comprises in substantial part at least one sulphonate of the formula RS03X
in which R is di-alkylaryl including aryl is phenyl, toluyl or xylyl having attached thereto two linear alkyl groups with equal or different chain length, but each containing 11-20 carbon atoms in the alkyl chain and X is sodium, potassium, lithium or ammonium. Such ~ulphonates will be further on denoted as Cll-C20-dialkylarenesulphonates.
The di-alkylarenesulphonate-containing steam-foam-forming mixture suitably includes an aqueous solution of electrolyte and advantageously further also includes a substantially noncondens-able gas, with each of the surfactant, electrolyte and gas com-ponents being present in proportions effective for steam-foam-formation in the presence of the reservoir oil. The invention also relates to the di-alkylarenesulphonate-contalning steam-foam-forming mi~tures which are described herein.
The invention is uaeful where it is desirable to remove oil from, or displace oil within, a subterranean reservoir. For example, the invention can be used to move oil or an emulsion of oil and water away from a well borehole in a well-cleaning type of operation, and/or to dlsplace oil into a producing location in an oil-recovery operation.
In particular, the present invention re]ates to a process for recoverlng oil from a subterranean reservoir, comprising:
injecting steam and producing fluid at horizontally spaced locations withln a portion of an oil reservoir in which the disposition of a seeam flow path is determined by the effect o~
gravity and/or oil distribution, rather than b~ing substantially confined wi~hin at least the one most permeable layer of reservoir rocks;
advantageously malntaining raees of steam in;ecting and fluid production such that a steam channel has been extended from the injection location;
changing the composition of the fluid being injected from steam to a steam-foam-forming mixture by addition of a linear Cll-C20-di-alkylarenesulphonate-containing compound, whilst continuing to produce fluid from the reservoir;
correlating the composition of the steam-foam-formlng mixture with the properties of the rocks and fluids in the reservoir so that the pressure required to in~ect the mixture and the foam it forms or comprises into and through the steam channel exceeds that required for steam alone but is less than the reservoir fracturing pressure; and ad~usting the composition of the fluid being in~ected into the steam channel to the extent required to maintain a flow of both steam and foam within the channel in response to a relatively high pressure gradlent at which the oil displacing and channel expanding effects are slgnificantly greater ehan those provided by steam alone, without plugging the channel.
The inventlon al~o relates to an oil recovery process in which steam is cyclically in~ected into and fluid is backflowed from a subterranean heavy oil reservolr which is susceptible to gravity override and tends to intake and retain undesirably large proportions of the in~ected fluid. This process comprises:
~5~
in~ecting steam mixed with a linear Cll-C20-di-alkylarene-sulphonate-containing steam-foam-forming compound which is arranged for forming a steam foam which (a) can be displaced through the pores of the reservoir, withoue plugging any port-lon of the reservoir 9 in response to a pressure ~hich exceeds that required for displacing steam through the reservo~r but i8 less than the fracturing pressure of the reservoir, and (b) can be weakened by contact wi~h the reservoir oil to an extent such that the weakened foam is significantly more mobile in reservoir oil-containing pores of a porous medium than in oil-free pores of that medium;
injecting the steam-foam-forming mixture at a rate equivalent to one which is slow enough to cause the foam formed by that mixture to advance more rapidly through the pores of a reservoir lS oil-containing permeable medium than through the pores of a substantially oil-free permeable medium; and backflowing fluid from the reservoir after a steam soak time sufficient to condense part or all of the steam in the in~ected steam-foam-forming mixture. The steam-foam-forming mixture preferably comprises steam, a noncondensable gas, a linear Cll-C20-di-alkylarenesulphonate surfactant and an electrolyte.
The invention provides unobvious and beneficial advantages in oil displacement procedures by the use of the di-alkylarene-sulphonate surfactant in the steam-foam-forming composi~ions. For example, where a steam-foam-forming mixture contains such a surfactant and an electrolyte in proportions near optimum for foam formation, the present surfactant components provide exceptionally strong steam foams having mobllities many times less than those of steam foams using other surfactants. In nddition, significant reductions are reached in the mobilities of the steam foams at concentrations which are much less than those required for equal mobility reductions by the 3urfactants which were previously considered to be the befit available for such a purpose. The use of the present di-alkylarenesulphonate surfactant components involves no problems with respect to thermal and hydrolytic stability. ~o ~.2~
chemlcal or physical deterioration has been detectable in the presen~ alkylarenesulphonate surfactants that were recovered along with the fluids produced during productions of oil from subterranean reservoirs. In each of those types of sulphonate surfac~ants the sulphur atoms of the sulphonate groups are bonded directly to carbon atoms. The surfactants which were recovered and tested during the production of oil had travelled through the r~servoirs at steam tempera~ures for significant times and distances.
The present Cl1-C20-di-alkylarenesulphonate-containing steam foams have been found to represent a substantial improvement in mobility reduction over foams based on the mono-alkylaryl sulphonates e.g., dodecylbenzene sulphonates. The foams to be used according to the present invention represent also substantial improvement over the C16-C18 alpha-olefinsulphonate-containing foams.
The present invention further relates to compositions con-taining at least one C11-C20-di-alkylarenesulphonate, and steam, optionally electrolyte, and optionally noncondensable gas, that are suitable for use in oil-displacing and/or producing processes.
Of particular interest in this respect are steam-foam-forming compositions consisting essentially of (a~ water, which ls present in the composition, at a temperatùre substantially equalling its boiling temperature, at the pressure of the composi~ion, in both a liquid phase and a vapour phase; (b) a surfactant component present in the liquid phase of the composition in an amount between O.a1 and 10 percent by ~eight, calculated on the weight of the liquid phase, said surfactant component comprising in 8ub-stantial part at least one C11-C20-dl-alkylarenesulphonate; (c) an electrolyte present in the liquid phase of the composition in an amount between 0.001 percent by welght (calculated on the weight of the liquid phase) and an amount tending to partition the surfactant into a aeparate liquid phase; and (d) a noncondensable gas present in the vapour phase in an amount between about 0.0001 and 0.3 percent by mol, calculated on total mols in the vapour phase.
Illustrative of the di-alkylarenesulphonate surfactant~
suitably employed in steam-foam drive processes of enhanced performance, according to the invention, are the di-alkylarene-sulphonates obtalned by reacting a linear Cll-C20-di-alkylbenzene linear Cll-C20-di-alkyltoluene and/or linear Cll-C20-di-alkylxylene with sulphur trioxide followed by neutralization of the sulphonic acid. Particularly suitable for purposes oE the invention is a sulphonate derived from substantially linear 10 Cll-C20-di-alkyl-benzene.
Different reservoir materials have different debilitating effects on the strength of a steam foam. Tests should there-fore be carried out to determine the sulphonates or sulphonate-containing steam-foam-forming compositions that perform optimally in a given reservoir. This is preferably done by testing the influence of specific sulphonates on the mobility of a steam-containing fluid having the steam quality selected for use in the reservoir in the presence of the reservoir material.
Such tests are preferably conducted by flowing steam-contain-ing fluids through a sand pack. The permeability of the sand packand foam-debilitating properties of the oil in the sand pack should be at least substantially equivalent to those of the reservoir to be treated. Comparisons are made oE the mobility of the steam-containing fluid with and without the surfactant component.
The mobility is indicated by the substantially steady-state pressure drop between a pair of points located between the inlet and outlet portions of the sand pack in positions which are sub staneially free of end effects on ehe pressures.
Some laboratory tests to determine steam mobility will now be described with reference to Figures 1 and 2.
Figure 1 shows schematically a sand pack test apparatus which can be made of currently avnilable apparatus components. The apparatus consists of a cylindrical tube 1 that is ~00 mm long and has a cross-sectional area of 8 cm2. Such a tube is preferably arranged for a horizontal flow of fluid from an inlet 2 to an 3~
outlet 3. The tube is preferably provided with 5 pressure taps 4, 5, 6, 7 and 8. The location of the first pressure tap 4 is at a distance of 150 ~m from the inlet 2. The locations of the other taps are chosen so as to divide the part of the tube 1 situated behind tap 4 into equal parts of 50 mm. The tube l contains a permeable and porous column of sultable material, such as a sand pack, which is capable of providing an adequately reallstic laboratory model of a subterranean reservoir.
At the inlet end 2, the sand pack or equivalent column of permeable material is arranged to receive separate s$reams of steam, noncondensable gas such as nitrogen, and one or more aqueous liquid solutions or dispersions containing a surfactant to be tested and/or a dissolved or dispersed electrolyte. Some or all of those components are in~ected at constant mass flow rates proportioned so that steam of a selected quality, or a selected steam-containing fluid or composition, or a steam-foam-forming mixture of a selected steam quality can be injected and will be substantially homogeneous substantially as soon as it enters the face of the sand pack.
In the tests, steam-foam-forming mixtures are compared with and without surfactant components added thereto, by measuring pressure gradients formed within a sand pack during flows through the pack at the same substantially constant mass flow rate.
Numerous tests have been made of different steam-foam-forming mixtures using sand packs composed of a reservoir sand and having a high permeability, such as 10 darcys. The pressures were measured with pressure detectors (not shown) (such as piezoelectric devices) installed at the inlet 2 and at the taps 4, 5, 6, 7 and 8 of the tube 1. The results of such tests have proven to be generally comparable with the results obtained in the field.
In the laboratory tests, the steam-foam-forming components were in~ected at constant mass rates until substantially steady-state pressures were obtained at the lnlet and at the taps. The ratio between the steady-state pressures at the taps during flow of steam mixed with the foam-forming surfactant component and the steady-state pressure at the taps during flow of the steam by itself are indicative for the mobility reduction. The higher this ratio, ~he stronger ehe steam foam and the higher the mobllity reduction caused by the steam-foam forming mixture.
Figure 2 illustrates the results of comparaeive tests with steam and various steam-foam-forming mixtures in sand packs containing Oude Pekela Reservoir sand having a permeability of 7 darcys. The backpressure was 21 bar, corresponding with a tem-perature of 215 C. The steam injection rate was 600 cm9/min, having in the water phase containing 0.5 %w sodium C8-C10-di-alkylbenzenesulphonate. The figure shows the ~ariation of the pressure difference in bar (~-axis) with distance in centimetres (X-axis) from the pack inlet 2. The pressures were measured at the inlet 2, at the taps 4, 5, 6, 7 and 8, and at the outlet 3 of the pipe 1 of Figure 1. Curve A relates to the displacement wherein a mixture of 85% quality steam, having in the water phase containing 0.5 %w sodium C8-C10-di-alkylbenzene-sulphonate, was used as a displacing composition.
Curve B relates to using a steam-containing fluid having a steam quality of 85% and a water phase which contains 0.5% by weight of a surfactant. In the Curve B test, the surfactant was a linear sodium Cll-C12-di-alkylbenzenesulphonate.
Curve C relates to using the mixture used for Curve B except that the surfactant was a linear sodium C13-Cl~-di-alkylbenzene-sulphonate.
To all surfactant solutions 0.25 /Ow sodium Cl~ C16 a-olefin sulphonste had been added ln order to merease the solubility of the sodlum di-alkylbenzenesulphonates.
The greatly improved steam permeability reduction performance of the presently described C11-C20-di-alkylarenesulphonate-containing surfactant component i9 clear from the Curves B and C
as compared to the Curve A in Figure 2.
Composition6 and procedures suitable for use in the present invention For purposes of the present invention, the surfactant component of the steam-foam-forming mixture is necessarily comprised in substantial part o linear Cll-C20-di-alkylarenesulphonate.
Mat~rials of this class but with a much shorter alkyl chain have heretofore found commercial utility, for example, in detergent formulations for industrial, household and personal care application.
A class of di-alkylarenesulphonates very suitable for use in the present invention is that derived from a particular class of olefins, which may be defined for present purposeR in terms of the configuration and number of carbon atoms in their molecular struceure. These olefins preferably have a carbon number of 13-14.
In terms of molecular structure, these olefins are aliphatic and mainly linear. Either alpha- or internal olefins are considered suitable for the alkylation route chosen to produce the products to be used according to the invention. For purposes of derivation of the di-alkylarenesulphonates for use in the process according to the invention, olefins are advantageously applied in which at least 90% of the molecules are alpha-olefins.
Particularly attractive are sulphonates derived from the SHOP alpha-olefins (trademark) sold by Shell Chemical UK, in part for their linear structure and high alpha-olefin content, i.e , greater than 95% in each case. The SHOP alpha-olefins are prepared by ethylene oligomerization. Products having a high content of internal Cll-C20-olefins are also commercially manufactured, for instance, by the chlorination-dehydrochlorination of paraffins or by paraffin dehydrogenation, and can also be prepared by isomerization of alpha-olefins. Internal~olefin-rich products are mamlfactured and sold, for example, by Shell Chemical UK.
For preparation of di-alkylarenesulphonates, the olefins as described above are subJected to reaction wlth benzene, toluene or xylene. The di-allcylbenzene, di-alkyltoluene or di-alkylxylene isomers are reacted with sulphur trioxide. The term "sulphur trioxide" as used in the present specification and clalms is intended to include any compounds or complexes which contain or yLeld S03 for a sulphonatlon reaction as well as S03 per se. This reaction may be conducted according to methods well known in the chemical arts, typically by contact of a flow of dllute S03 vapour with a thin film of liquid alkylate at a temperature in the range of about 5 to 50~C. The reac~ion between the S03 and the alkylate yields a sulphonlc acid which is neutralized by reaction with a base, preferably an alkali metal hydroxide3 oxide, or carbonate.
The specific composition of di-alkylarenesulphonates prepared as described above (and also, for instance, the ~ethods used for sulphonation, hydrolysis, and neutralization of the specified olefins) have not been found to be a critical factor to the performance of the surfactant in the steam foam process according to this in~ention. In this regard, it is observed that factors which have conventionally governed the choice of sulphonation conditions, e.g., product colour, clarity, odour, etc., do not carry the same weight in the preparation of di-alkylarene-sulphonates for purposes of use in the process according to the invention that they have been accorded in detergent manufacture.
Consequently, reaction conditions outside of those heretofore considered desirable for alkylate sulphonation are still suitably applied in the preparation of surfactant components suitable for use in the steam-foam-forming mixture.
For purposes related to maintaining product stability, conventional manufacture typically yields a dilute solution or dispersion of the di-allcylarenesulphonates, for instance, products with a 15-30 Y~wt actlve matter content ln water. Such products may be directly applied to the preparation of steam-foam forming mixtures for purposes of this invention.
Suitable alkylarenesulphonates, generally prepared by methods such as descrlbed above, are themselves commercially available products.
The stren8th of the foam formed by the steam-foam-forming composltion including dl-alkylarenesulphonate tends to increase with increases in the proportion of the surfactant and/or electrolyte components of the composition. Also, there tends to be an optimum ratio of surfactant and electrolyte components at which the surface activity of the composition is maximized.
The steam-foam-forming composition according to the present ~nvention can Eorm a seeam-foam capable of reducing the effective mobility of the steam to less than about l/lOth and even to 1150th-1175th of the mobility it would have within a permeable porous medi~m in the absence of t~e surfactant.
The steam used in the present process andlor compositions can be generated and supplied in the form of substantially any dry, wet9 superheated, or low grade steam in which the steam condensate andjor liquid components are compa~ible with, and do not inhlbit9 the foam forming properties of the foam~forming components of a steam-foam-forming mixture according to the present invention. The steam quality of the steam as generated andlor amount of aqueous liquid with which it is mixed be such that the steam quality of the resulting mixture is preferably from 10 to 90%. The desired steam-foam is advantageously prepared by mixing the steam with aqueous solution(s) of the surfactant component and optionally, an electrolyte. The water content of these aqueous solutions muse~ of course, be taken into account in determining the steam quality of the mixture being formed.
Suitably, the noncondensable gas advantageously used in a steam-foam-forming mixture according to the present invention can comprise substantially any gas which (a) undergoes little or no condensation at the temperatures (100-350 C) and pressures (1-100 bar) at which the steam-foam-forming mixture is preferably injected into and displaced through the reservoir to be treated and (b) is substantially inert to and compatible with the foam-forming surfactant and other components of that mixture. Such a gas is preferably nltrogen but can comprlse other substantlally lnert gases, such as air, ethane, methane, flue gas, fuel gas, or the like. Suitable concentrations of noncondensable gas in the steam-foam mixture fall in the range of from 0.0001 to 0.3 mole percent ~uch as 0.001 and 0.2 mole percent, or between 0.003 and 0.1 mole percent of the gas phase of the mixture.
Suitably, the electrolyte used should have a composition similar to and should be used in a proporeion similar to those described as suitable alkali metal salt electrolytes in the above-mentioned US~ patent speciflcation 4,086,964. An aqueous solution may be applied that contain~s an amount of electrolyte substantially equivalent in salting-out effect to a sodium chloride concentration of from O.OOl to 10% (but less than enough to cause significant salting out) of the liquid-phase of the steam. Some or all of the electrolyte can comprise an inorganic salt, sush as an alkali metal salt, an al~ali metal halide, and sodiutn chloride.
Other inorganic salts, for example, halides, sulphonates, carbonates, nitrates and phosphates, in the form of salts of alkaline earth metals, can be used.
Generally stated, an electrolyte concentration may be applied which has approximately the same effecs on mobility reduction of the foam as does a sodium chloride concentration of between O.OOl and 5 percent by weight (but less than a salting out-inducing proportion) of the liquid phase of the steam-foam-forming mixture.
The electrolyte concentration may be between O.OOl and 10 percent calculated on the same basis.
In compounding a steam-foam-forming mixture or composition in accordance with the present invention, the steam can be generated by means of substantially any of the commercially available devices and techniques for steam generation. A stream of the steam being ln~ected lnto a reservoir is preferably generated and mixed, in substantlally any surface or downhole location, with selected proportions of substantially noncondensable gas, aqueous electrolyte solution, and foam-formlng surfactant. For example, in such a mixture, the quality of the steam which is generated and the concentration of the electrolyte and surfactant-containing aqueous liquid wlth which it is mlxed are preferably arranged so that (l) the proportion of aqueous liquid mixed with the dry steam which i9 in~ected into the reservoir is sufficient to provide a steam-containing fluid having a steam quality of from 10-90% (preferably from 30-85~); (2) the weight proportion of surfactant dissolved or dispersed in the aqueous liquid ls from O.Ol to lO.O (preferably from 1.0 to 4.0); and (3) the amount of noncondensable gas is from 0.0003 to 0.3 mole fraction of the gas phase o the mixture.
Claims (7)
1. A process for displacing oil within an oil-containing sub-terranean reservoir by flowing a steam-containing fluid in con-junction with a surfactant component through a relatively steam-permeable zone within said reservoir, characterized in that a surfactant component is employed which comprises in substantial part at least one sulphonate of the formula RSO3X in which R is di-alkylaryl aryl being phenyl, toluyl or xylyl having attached thereto two linear alkyl groups with equal or different chains and X is sodium, lithium, potassium or ammonium.
2. A process according to claim 1, characterized in that an electrolyte is employed in the flow within the reservoir in conjunction with the steam-containing fluid.
3. A process according to claim 1 or 2, characterized in that a substantially noncondensable gas is employed in the flow within the reservoir in conjunction with the steam-containing fluid.
4. A process according to claim 1, characterized in that the surfactant component comprises in substantial part sulphonate obtained by reacting a linear di-alkylbenzene, linear di-alkyltoluene and/or linear di-alkylxylene of which each of the alkyl chains contains from 11 to 20 carbon atoms with sulphur trioxide followed by neutraliz-ation of the sulphonic acid.
5. A process according to claim 4, characterized in that the sulphonate is derived from linear C13-14-di-alkyltoluene, C13-C14-di-alkylbenzene or C13-C14-di-alkylxylene.
6. A process according to claim 1, characterized in that the aqueous liquid phase of the steam-containing fluid contains between about 0.01 and 10 percent by weight of alkylarenesulphonate.
7. A process according to claim 1, characterized in that an electrolyte is used up to 10% in the liquid phase to enhance the performance of the surfactant.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB8624361 | 1986-10-10 | ||
| GB8624361A GB2196665B (en) | 1986-10-10 | 1986-10-10 | Steam foam process |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1295118C true CA1295118C (en) | 1992-02-04 |
Family
ID=10605556
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000546987A Expired - Fee Related CA1295118C (en) | 1986-10-10 | 1987-09-16 | Steam foam process |
Country Status (4)
| Country | Link |
|---|---|
| CA (1) | CA1295118C (en) |
| DE (1) | DE3734075C2 (en) |
| GB (1) | GB2196665B (en) |
| NL (1) | NL8702293A (en) |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102838978A (en) * | 2012-09-18 | 2012-12-26 | 济南大学 | Preparation method and application of autogeneration gas foam composite oil-displacing agent under shaft |
| US10487636B2 (en) | 2017-07-27 | 2019-11-26 | Exxonmobil Upstream Research Company | Enhanced methods for recovering viscous hydrocarbons from a subterranean formation as a follow-up to thermal recovery processes |
| US11002123B2 (en) | 2017-08-31 | 2021-05-11 | Exxonmobil Upstream Research Company | Thermal recovery methods for recovering viscous hydrocarbons from a subterranean formation |
| US11142681B2 (en) | 2017-06-29 | 2021-10-12 | Exxonmobil Upstream Research Company | Chasing solvent for enhanced recovery processes |
| US11261725B2 (en) | 2017-10-24 | 2022-03-01 | Exxonmobil Upstream Research Company | Systems and methods for estimating and controlling liquid level using periodic shut-ins |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4967837A (en) * | 1989-03-31 | 1990-11-06 | Chevron Research Company | Steam enhanced oil recovery method using dialkyl aromatic sulfonates |
| US7809538B2 (en) | 2006-01-13 | 2010-10-05 | Halliburton Energy Services, Inc. | Real time monitoring and control of thermal recovery operations for heavy oil reservoirs |
| US7770643B2 (en) | 2006-10-10 | 2010-08-10 | Halliburton Energy Services, Inc. | Hydrocarbon recovery using fluids |
| US7832482B2 (en) | 2006-10-10 | 2010-11-16 | Halliburton Energy Services, Inc. | Producing resources using steam injection |
Family Cites Families (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3770056A (en) * | 1971-07-02 | 1973-11-06 | Continental Oil Co | Method of increasing recovery of petroleum from subterranean formations |
| US4452708A (en) * | 1982-02-18 | 1984-06-05 | Exxon Production Research Co. | Oil recovery method using sulfonate surfactants derived from extracted aromatic feedstocks |
| US4540050A (en) * | 1984-02-03 | 1985-09-10 | Texaco Inc. | Method of improving conformance in steam floods with steam foaming agents |
| CA1247850A (en) * | 1984-03-26 | 1989-01-03 | Renee Janssen-Van Rosmalen | Steam foam process |
| GB2156400B (en) * | 1984-03-26 | 1987-08-26 | Shell Int Research | Steam foam process |
| CA1248343A (en) * | 1984-04-03 | 1989-01-10 | Howard P. Angstadt | Stable forms of polyalkylaromatic sulfonates |
-
1986
- 1986-10-10 GB GB8624361A patent/GB2196665B/en not_active Expired - Fee Related
-
1987
- 1987-09-16 CA CA000546987A patent/CA1295118C/en not_active Expired - Fee Related
- 1987-09-25 NL NL8702293A patent/NL8702293A/en not_active Application Discontinuation
- 1987-10-08 DE DE3734075A patent/DE3734075C2/en not_active Expired - Fee Related
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102838978A (en) * | 2012-09-18 | 2012-12-26 | 济南大学 | Preparation method and application of autogeneration gas foam composite oil-displacing agent under shaft |
| CN102838978B (en) * | 2012-09-18 | 2014-12-24 | 济南大学 | Preparation method and application of autogeneration gas foam composite oil-displacing agent under shaft |
| US11142681B2 (en) | 2017-06-29 | 2021-10-12 | Exxonmobil Upstream Research Company | Chasing solvent for enhanced recovery processes |
| US10487636B2 (en) | 2017-07-27 | 2019-11-26 | Exxonmobil Upstream Research Company | Enhanced methods for recovering viscous hydrocarbons from a subterranean formation as a follow-up to thermal recovery processes |
| US11002123B2 (en) | 2017-08-31 | 2021-05-11 | Exxonmobil Upstream Research Company | Thermal recovery methods for recovering viscous hydrocarbons from a subterranean formation |
| US11261725B2 (en) | 2017-10-24 | 2022-03-01 | Exxonmobil Upstream Research Company | Systems and methods for estimating and controlling liquid level using periodic shut-ins |
Also Published As
| Publication number | Publication date |
|---|---|
| GB2196665B (en) | 1990-06-20 |
| DE3734075A1 (en) | 1988-04-14 |
| GB2196665A (en) | 1988-05-05 |
| DE3734075C2 (en) | 1996-10-17 |
| GB8624361D0 (en) | 1986-11-12 |
| NL8702293A (en) | 1988-05-02 |
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