JPS59173485A - Micelle solution for recovering petroleum - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] Does the present invention provide oil from underground reservoirs? Regarding the micellar solution used in the micellar attack method for oil recovery, more specifically, it is an oil recovery method that can be applied to underground reservoirs containing all oil layers with a very wide range of salt concentrations to recover oil with a high oil recovery rate. micellar solution for use.

Only a portion of the oil contained in underground oil reservoirs can be recovered using primary recovery methods such as bombing.

Most of it remains in underground reservoirs. In order to recover the oil that cannot be recovered in the next transaction, water or gas is injected into the underground reservoir to increase the pressure, give fluidity to the oil, and recover it. A secondary recovery method in which the oil in the reservoir is partially combusted to heat the underground reservoir and toughen it to lower the viscosity of the oil and increase its fluidity for recovery. Various tertiary recovery methods have been proposed that combine these secondary recovery methods, such as an improved secondary recovery method in which surfactants or aqueous polymers are poured into a river, and these are generally combined with forced oil recovery methods. (Enhanc
edOil Recover7) (E, O, L)
It is called.

E using surfactant, 0. In R, a method that has been attracting attention in recent years involves making a transparent microemulsion from water and oil such as petroleum or N/IiI, and injecting this microemulsion, also called a micellar solution, into an underground reservoir to extract oil. There is a Mitara attack method to collect the .

There are many precursor technologies for this micellar attack.
No. 13786, No. 374034.3, @J No. 398
No. 3940, No. 39905t5, No. 4o174o
No. 5 and J4o59i54. Among these prior art.

Surfactants that can be used in the preparation of micellar solutions include a variety of anionic, nonionic, and cationic surfactants, including 2-petroleum sulfonates, alkylacyl sulfonates, dialkyl sulfosuccinates, and alkanes. sulfonate, polyoxyethylene alkyl ether sulfate, α-olefin sulfone), polyoxyethylene alkyl ether, polyoxyethylene alkyl phenyl ether-polypod alcohol fatty acid ester, alkyltrimethylammonium salt, dialkyldimethylammonium salt, etc. There is.

The micellar bath liquid requires that the interfacial tensions between the oil and the microemulsion and between the reservoir water and the microemulsion are sufficiently low, respectively, and that the salt concentration of the reservoir water changes during sweeping, in order to achieve high oil recovery. 7. The microemulsion remains stable even when HfL, which requires small changes in interfacial tension6.In addition, the degree of exposure to oil layer water varies widely from low to high.In addition, the micellar solution must have salt tolerance across various salt concentrations. In addition, the amount of micellar solution injected into the underground reservoir is very large, so the micellar solution must be cheap.

The present invention was made with the aim of solving the problems of cfL et al. In the micellar bath liquid used as injection fluid for forced petroleum recovery called VC, internal olefin sulfonate having 10 to 26 carbon atoms (hereinafter referred to as (abbreviated as 10S) (f- micellar bath solution used and provided).

The micellar solution of the present invention suitable for convenient use as an injection fluid for oil strength 11ilJ recovery t-1 hydrocarbons, about 2 to about 90 coulometric ratio, IO8 with 4 lateral 92 %, carbon number 10 to 3°
It is a clear microemulsion containing from about 3 to about 30% by weight of a surfactant having a woody fraction and from about 11 to about 20% by weight of a surfactant adjuvant.

Water that can be used in the micellar solution of the present invention.

Any of soft water, brackish water, and prine water may be used.For example, any of rainwater, river water, lake water, groundwater, oil layer water, and seawater can be used freely.

Since the micellar bath solution μ of the present invention uses IO8, which has good salt resistance and hard water resistance, as an essential component of the surfactant,
Even if the salt concentration of the prine is about 10%, it can be tolerated. 2 By combining other surfactants and selecting surfactant auxiliaries, it is possible to use prine with a concentration of up to about 15%. Regarding metal ions, the presence of about 5,000 PPM (about 2.6% as MgS04) is permissible.The inorganic salt concentration of water that can be used for producing the micelle solution of the present invention ranges from O to approx. Even if you receive one, it will be about 0.5 to 12% by weight, especially about 1 to about IO weight%.
is preferred. Examples of alkali metal salts contained in water containing inorganic salts (prine) are NaCl, KCI.

Na 2 SO 4 and 2S O 4 are representative. For example, seawater has an inorganic salt concentration of about 3.5%, and
The valent metal ion is converted to Mg ion Ic, which is approximately 1,600
Although it contains PPM, such a salt concentration falls within the preferred range b of the present invention.

The ros contained in the micellar solution of the present invention as an essential component of the surfactant is expressed by the general formula % (wherein R2R is a linear or branched saturated hydrocarbon group each having 1 or more carbon atoms). and the sum of the carbon numbers of R and R/ is 8 to 24), and the vinylene type monoolefin having 10 to 26 carbon atoms, preferably 12 to 24 carbon atoms, is used as a woody component, and according to Yang Kai, approximately 3 It is produced by sulfonating an internal olefin containing 311 fft% (approximately 1/3 of the olefin) of three-substituted monoolefin, neutralizing it with an appropriate base, and hydrolyzing it if necessary. The IO8 produced in this way usually contains about 1 to 6,040% by weight of an alkenylsulfone having a double bond, while the monosulfone) 1'-+80% by weight.
The above, and the disulfonates have a weight of about 20% or less. Of course, by selecting the sulfonation conditions and hydrolysis conditions, a different proportion of l08t-
It is also possible to manufacture. Generally, as the number of carbon atoms in the internal olefin increases, the proportion of alkenyl sulfonate tends to increase, and as the molar ratio of the sulfonating agent to 1 during sulfonation increases, the proportion of disulfonate tends to increase.

The IO8 used in this invention must have a disulfonate content of about 20% by weight or less. If the disulfonate content is higher than this, the interfacial tension lowering ability of IO8 will be impaired, and a micellar solution with high oil recovery rate cannot be produced. Disulfonate in IOS increases salt tolerance without impairing interfacial tension lowering ability if it is a polyelectrode, and improves resistance to changes in brine salt concentration, so the content of disulfonate is approximately 0.5~ 15 weight, especially about 1-1
Preferably it is 2% by weight.

10iS used in the present invention is selected from alkali metal salts and min salts. Preferred countercation triNa.

K, Mg, Ca, NH4 and IJ'alkanol ammonium.

Suitable for the present invention: I For example, the number of carbon atoms +
2,14. +6. +8.20,22,24°12~16
．． 13-14.13-16.14-16.14-18.
, +5-↓8,16~18.16~20°17~20.
18-20 and 20-24 IO8 and mixtures thereof.

The micellar bath liquid VCL-X of the present invention contains a surfactant of about 1 to
Although it contains 30% by weight, the oil-water interfacial tension is low and the cost is 1, so the surfactant content) 1 is about 3 to about 2
Preferably, the weight is 5. The proportion of IO8 having 10 to 26 carbon atoms in the surfactant is at least 50% by weight,
The content is preferably 60% by weight or more.

Hydrocarbons used as oil phase components of the present invention include petroleum,
Liquefied petroleum gas, crude gasoline (naphtha), oil, diesel oil 2
Although any heavy oil can be used, it is preferable to use recovered regular petroleum oil, considering its low price, easy availability, and similarity in composition to petroleum in underground reservoirs.

The proportion of hydrocarbons in the micellar solution of the present invention ranges from about 2 to about 90%.
Although it is heavy Ti%, it is economically disadvantageous to use a large amount of hydrocarbons, so O/W type emulsion is preferable.
Therefore, the proportion of hydrocarbons is preferably about 3 to about 40% by weight.

In the micellar solution of the present invention, the surfactant auxiliary is an essential component that works together with the surfactant to form a microemulsion. The surfactant used in the present invention is a compound containing an alcoholic hydroxyl group, and is preferably a compound having the general formula % (% formula %) (where n is a number from 0 to about 4 and -R is n- In the group 0, an alkyl group having 4 to 8 carbon atoms is alcoholic, and when n is not 0, an alkyl group or alkenyl group having 6 to 15 carbon atoms, a phenyl group, or an alkyl group having 7 to 7 carbon atoms.
(16) is an alkylphenyl group (the aliphatic group may be linear or branched). Specific examples of such alcohols include butanols, pentanols, hexanols, 2-ethylhexanol, other octatools, polyoxyethylene hexyl ether (n=1')-polyoxyethylene tesyl ether ( n=2), polyoxyethylene tridecyl ether (rz=4), polyoxyenalene phthylphenyl ether (n=2).

Polyoxyethylene nonylphenyl ether (n=3)
-bo9oxyethine dodecyl phenyl ether (n =
4) etc.

The surfactant used in the present invention is used in a range of about 0.1 to about 20 ml during micellar dissolution, but it is important for the stability of microemulsions and the ability to reduce tension in the oil-water world. From this point of view, it is preferred that about i-J'J15.1% by weight be used.

The micellar solution of the present invention contains IC) S having 10 to 26 carbon atoms as an essential surfactant component, but optionally contains other surfactants. Can be used together. Examples of such surfactants include petroleum sulfonate, alkylbenzene sulfonate, polyoxyethylene alkyl ether nanofluoride, dialkyl sulfonate,
α-olefin sulfonates, paraffin sulfonates, soaps.

Examples include anionic surfactants and nonionic surfactants such as higher alcohol ethoxylates, alkylphenol ethoxylates, alkylphenol ethoxylates, esters, fatty acid alkylolamides, and polyoxyethylene fatty acid amides.

The micellar solution of the present invention constitutes a microemulsion,
J.
Although it is possible to adjust the viscosity by adjusting the viscosity, it is also possible to use a thickener such as a water-soluble polymer. Such thickeners include (eg, hederopolysancalide produced by microorganisms, naphthalene sulfonic acid formalin condensates, polyacrylamides, polyacrylates,
Examples include hydroquine ethyl cellulose and carboxymethyl cellulose.

The micelle @ solution of the present invention can be used in known emulsion manufacturing methods.
It can be easily produced, and the addition of each ingredient is 1 m
The mixing method, stirring method, temperature, pressure, etc. can be selected arbitrarily.

The method for recovering oil from underground storage N using the micellar bath liquid of the present invention is similar to the known micellar bathing method, in which a micellar solution is injected from at least one injection well toward an oil-producing well, and then at least one One kind of driving fluid, oil, can be recovered. At this time, the injection and dispersion of the micelle solution is suitably 5 to 25% of the porosity of the underground reservoir.

The salt concentration of oil layer water in an underground reservoir to which the micellar bath liquid of the present invention can be applied is suitably from O to about 1 part by volume.

・It's about 01 to about 12i, especially about 0.5
1 to about 101 folds is preferable.The concentration of the water used for the production of the liquid and the salt concentration of the oil layer water I-1: It is not necessary, but it is Considering the change in salt concentration 1, it is preferable to be in the opposite direction.

Since the micelle solution of the present invention contains IOS having a disulfonate content of about 20% by weight or less as a wood component of the surfactant, it has good salt control properties and hard water resistance, and can be used in applications ranging from soft water to high salt concentration prine. Microemulsions can be formed in a wide range of salt concentrations, and the interfacial tensions between water and microemulsions and between oil and microemulsions are very small, making them resistant to changes in salt concentration (1) Can be freely used in soft water, seawater, and oil reservoir water with high salt concentration; (2) the injected micellar solution is hardly affected by the inorganic salts present in underground reservoirs; (3) it can be used to change from low viscosity petroleum to high viscosity oil. (4) A stable microemulsion can be maintained in the trench where the oil bank is formed in the underground reservoir, resulting in excellent effects such as achieving a high oil recovery rate. be able to.

The present invention will be explained in more detail with reference to Examples 1c below, but it goes without saying that the present invention is not limited to these Examples. The component proportions in each sample used in the experiment are by weight unless otherwise indicated.

Example 1 Varying the amount of disulfonate contained in the active ingredient as a surfactant -r: C14 to C1B I OS-N,
a1'rt is petroleum sulfonate (Liteco TBS-I)
Q) 10.5%, amyl alcohol 4.5% as a surfactant, 17% A heavy oil (ASTM No. 1 oil) as an oil, and 68 chloride K by dissolving 8% sodium chloride in deionized water as a brine. was weighed into a beaker and stirred for 100,100 rpm at a temperature of 71°C to prepare a microemulsion. At this time, the ability of the sample to form a microemulsion, the ability to lower the interfacial tension of the prepared microemulsion, and the oil recovery rate of the microemulsion were evaluated and determined.

The test results are listed in Table-1.

Used as a surfactant: IO8 is sulfonated and
The synthesis was performed by changing the molar ratio of internal olefin and S03 as raw materials in the reaction, and the amount of disulfone (DS) Fl contained in the active ingredient was adjusted.

For samples with low disulfonate content, extract and purify using inbutyl alcohol to adjust the content to the desired level.

For evaluation of microemulsion forming ability, the sample should be uniformly transparent at a temperature of 71°C, and the sample should be ○, opaque and suspended. × Bind.

The interfacial tension was measured using a spinning drop type interfacial tension meter at a temperature of 71°C in an appropriately diluted system.The zero oil recovery test was conducted with a permeability of approximately 500 mD, a porosity of approximately 20%, and a length of 28 crn.
Test method 6 uses a Berea sandstone core with a diameter of 3.8 cm.The core with a sufficiently saturated pline is loaded into a core holder, and A heavy oil is pressurized at a rate of 5 cc/m until A heavy oil no longer flows out. To. Next, a prine was forced in at the same speed and water flooding was performed to recover the heavy oil. Water flooding should be continued until the amount of heavy oil A contained in the spilled liquid is 0.1% or less.

The micellar attack method is carried out by placing the microemulsion to be press-fitted and the core holder in a constant temperature bath and maintaining the temperature at 71°C. First, the microemulsion is poured into a pore volume of 10 cm, followed by a polymer solution (xanthan gum 1000 PI) m prine solution). The ioo pore volume.

Finally, Pline'fc 100% pore volume was injected to collect A heavy oil. The press-fitting speed was 2 feet/day.

To evaluate the recovered oil, the moisture in the core after the test was recovered by an azeotropic method using toluene, the amount of moisture in the core was determined, and the amount was converted into the amount of oil recovered.

Table 1 Disulfonate content: O1 or less Example 2 C,4-cs8 I O8-Na I O, 5%, containing 7% disulfonate (based on active ingredient) as a surfactant;
4.5% amyl alcohol as a surfactant, 17% heavy oil A as oil, and an aqueous solution of a predetermined amount of sodium chloride dissolved in deionized water as a prine, or CaCt2'! in an aqueous sodium chloride solution. To prepare a symmicro emulsion, a total of 68 pieces of water bath liquid in which MKi2 was dissolved were placed in 9 beakers and stirred at a temperature of 71°C and 100 rpm for 30 minutes.

Evaluation of the microemulsion forming ability of the sample, measurement of the interfacial tension of the microemulsion, and oil recovery test using the microemulsion were performed in the same manner as in Example 1.

The test results are listed in Table-2.
a -CI6~C2oIO8-Mg or C20-C22
Weigh into a beaker 108-KNO, 5%, 4.5% amyl alulur as surfactant, 17% heavy oil A as oil, 68% aqueous solution dissolved in 8% 1 sodium chloride in deionized water as prine. , 10 at a temperature of 71℃
A microemulsion was prepared by stirring at 0 rpm for 30 minutes.

Evaluation of the ability of the sample to form a microemulsion, measurement of the interfacial tension of the microemulsion, and oil recovery test using the microemulsion were conducted in the same manner as in Example 1.

The test results are listed in Shio-3.

Below margin

Claims (1)

[Claims] 1. Water that may contain hydrocarbons and inorganic salts. In a micellar solution for petroleum recovery that is woody from surfactants and surfactant aids, the content of dinulphonate as a surfactant is approximately 20% by weight44. % or less carbon number 10-2
A micellar solution for petroleum recovery characterized by the use of No. 6 internal olefin sulfonate.