CN103937480B - A kind of organic base/surfactant binary composite oil-displacing system and preparation method thereof and application - Google Patents

Abstract

The present invention relates to a kind of organic base/surfactant binary composite oil-displacing system and preparation method thereof and application, organic base therein is ethylenediamine and ethanolamine, and surfactant is petroleum sulfonate. In the oil displacement system of the present invention, the consumption of surfactant is few, reduces cost, and anti-salt property is excellent, can effectively reduce the scaling tendency of formation water; Petroleum sulfonate can be reduced and reach 24.6% in the adsorbance of sandstone surface; Oil recovery factor amplitude can be improved and reach 19.5%; Oil water interfacial tension can be down to 10^-5The mN/m order of magnitude; Can alleviate or eliminate due to inside oil reservoir, oil well pipe fouling adverse effect, the tertiary oil recovery process of oil exploitation has good application.

Description

A kind of organic base/surfactant binary composite oil-displacing system and preparation method thereof and application

Technical field

The present invention relates to a kind of binary composite oil-displacing system including organic base and surfactant and preparation method thereof and application, belong to the chemical flooding field improving oil deposil erude petroleum recovery ratio.

Background technology

The chemical displacement of reservoir oil, is add various chemical agent in injecting water, to improve the displacement of reservoir oil of water and to involve performance, thus improving the oil production method of oil recovery factor. Being suggested from surfactant flooding technology and be used to, surfactant improves obtaining in various countries widely studied and applying of oil recovery factor as oil displacement agent.

At present, applying more oil displacement agent main body on oil field is petroleum sulfonate surfactant, drives the reservoir condition of theory and complexity and the production cost consideration in oil field based on general chemistry, and oil displacement agent generally requires that oil water interfacial tension reaches ultralow (10^-3MN/m) order of magnitude, simple use petroleum sulfonate generally can only reduce oil water interfacial tension value to 10^-1��10^-2The mN/m order of magnitude, does not reach the requirement of ultralow interfacial tension, and consumption is big, and cost is high. For ensureing to reach ultralow oil water interfacial tension, traditional method is (such as NaOH, Na by petroleum sulfonate and inorganic base₂CO₃��NaHCO₃Deng) composite, although oil water interfacial tension can be reduced, improve oil displacement efficiency, but inorganic base can react generation precipitation with the high price salt ion in stratum, is not merely blocked by earth bore road, causes earth formation to destroy, and cause that oil water well tube fouling is serious, bring great difficulty for exploitation further.

Chinese patent literature CN1865392A(application number: 200610044772.0) disclose a kind of highly efficiency compositional oil displacement agent being applied to tertiary oil recovery and preparation method thereof. This oil displacement agent is with petroleum sulfonate for primary surfactant, composite with other nonionic surfactant, anion surfactant, organic solvent and sodium chloride prepared. Although this composite oil displacement agent does not adopt alkali, but, reduce the poor effect of oil water interfacial tension, only reach 5 �� 10^-3The level of mN/m, and the consumption of surfactant is higher so that with high costs.

Adopt organic base can avoid reacting, with the high price salt ion in stratum, the problem generating precipitation, but, the selectivity of organic base is required higher by surfactant, different surfactants adds organic base and is likely to the difference of the impact on interfacial tension, the different organic base of identical surfactant compound is also different on the impact of interfacial tension, even without impact, and then do not reach the effect reducing interfacial tension, do not reach the effect improving recovery ratio yet. Therefore, find with low cost, interfacial tension reducing effect is obvious, and it can be avoided that react generation precipitation, infringement earth formation with the high price salt ion in stratum, block the surfactant in duct, stratum and the composite of alkali, become chemical displacement of reservoir oil field problem demanding prompt solution.

Summary of the invention

For the deficiencies in the prior art, the invention provides a kind of organic base/surfactant binary composite oil-displacing system and preparation method thereof and application, it is remarkably productive that this oil displacement system reduces oil water interfacial tension, salt-resistance is good, improve oil recovery factor amplitude big, and scaling tendency and the surfactant adsorbance in the earth formation of formation water can be reduced.

Technical scheme is as follows:

A kind of organic base/surfactant binary composite oil-displacing system, raw material components is as follows by weight percentage:

Petroleum sulfonate 0.10��0.30%, ethanolamine 0.10��0.15%, ethylenediamine 0.05��0.075%, excess water.

According to the invention it is preferred to, described organic base/surfactant binary composite oil-displacing system, raw material components is as follows by weight percentage:

Petroleum sulfonate 0.2��0.3%, ethanolamine 0.10��0.15%, ethylenediamine 0.05��0.06%, excess water.

According to the invention it is preferred to, described organic base/surfactant binary composite oil-displacing system, raw material components is as follows by weight percentage:

Petroleum sulfonate 0.20%, ethanolamine 0.15%, ethylenediamine 0.05%, excess water.

According to the invention it is preferred to, described organic base/surfactant binary composite oil-displacing system, raw material components is as follows by weight percentage:

Petroleum sulfonate 0.2��0.3%, ethanolamine 0.10��0.15%, ethylenediamine 0.05��0.075%, sodium chloride 0.5��2%, excess water.

According to the present invention, the preparation method of described organic base/surfactant binary composite oil-displacing system, step is as follows:

Take each component by proportioning, under room temperature, sodium chloride is added in water and stirs, then add petroleum sulfonate, ethanolamine and ethylenediamine at normal temperatures, stir, obtain organic base/surfactant binary composite oil-displacing system.

According to the present invention, described organic base/surfactant binary composite oil-displacing system is applied to the tertiary oil recovery process of oil exploitation.

Water of the present invention is the salinity clear water lower than 5000mg/L.

Organic base of the present invention/surfactant binary composite oil-displacing system can at NaCl concentration not higher than 50000mg L^-1, CaCl₂Concentration is not higher than 600mg L^-1, oil water interfacial tension is down to ultralow (10 not higher than under 80 DEG C of conditions by temperature^-3MN/m) order of magnitude, even reaches 10^-5The mN/m order of magnitude.

The present invention adopts organic base and surfactant compound, while playing surfactant and alkali synergism displacement of reservoir oil advantage, reduce the consumption of surfactant, improve the anti-salt property of oil displacement system, reduce surfactant in the absorption of sandstone surface, alleviate or eliminate due to inside oil reservoir, oil well pipe fouling adverse effect.

Beneficial effects of the present invention:

1, compared with inorganic base/surfactant binary composite oil-displacing system that organic base of the present invention/surfactant binary composite oil-displacing system is conventional with oil field, oil displacement efficiency is good, and the consumption of surfactant is few, reduces cost, anti-salt property is excellent, can effectively reduce the scaling tendency of formation water.

2, organic base of the present invention/surfactant binary composite oil-displacing system can reduce petroleum sulfonate and reaches 24.6% in the adsorbance of sandstone surface.

3, organic base of the present invention/surfactant binary composite oil-displacing system can improve oil recovery factor amplitude and reaches 19.5%.

4, oil water interfacial tension can be down to 10 by organic base of the present invention/surfactant binary composite oil-displacing system^-5The mN/m order of magnitude.

5, the preparation method of organic base of the present invention/surfactant binary composite oil-displacing system is simple, it is easy to popularization and application.

Detailed description of the invention

Below by specific embodiment, the invention will be further described, but institute of the present invention protection domain is not limited only to this.

Petroleum sulfonate described in embodiment is conventional commercial products, and Sinopec Shengli Oil Field branch company is on sale; Described ethanolamine and ethylenediamine, be commercially available prod, and product purity rank is chemical pure.

In embodiment, the test experiments instrument of interfacial tension is Texas500 type interfacial tensimeter, oil be Shengli Oil Field dewatered oil (60 DEG C, 6r/min viscosimetric 917mPa s).

In embodiment, the ion composition of simulated formation water is as shown in table 1.

Table 1 simulated formation water ion forms

According to oil and gas industry standard SY/T0600-2009 " oil field water Scaling Tendency Prediction ", CaCO₃The Forecasting Methodology of dirt has Davis-Stiff saturation index method and Ryznar index of stability method two kinds.

1. Davis-Stiff saturation index method

CaCO₃The Davis-Stiff saturation index method of Scaling Tendency Prediction is calculated according to formula (1), formula (2) and formula (3):

SI=pH-K-p [Ca]-pAlK(1)

$\mathrm{pAlK}=1g\frac{1}{2\left[{\mathrm{CO}}_3^{2-}\right]+\left[{\mathrm{HCO}}_3^{-}\right]}---\left(2\right)$

$\mathrm{\μ}=\frac{1}{2}(c_1{z}_1^2+c_2{z}_2^2+\·\·\·c_1{z}_i^2)---\left(3\right)$

SI fouling saturation index in formula;

The pH value of pH water sample;

K correction factor, during by different temperatures, ionic strength �� checks in the graph of a relation of adjusted coefficient K;

p[Ca]����Ca²⁺The negative logarithm of ion concentration (mol/L);

The negative logarithm of pAlK total alkalinity (mol/L);

����CO₃ ^2-The concentration of ion, mol/L;

����HCO₃ ^-The concentration of ion, mol/L;

�� ionic strength;

c_iThe concentration of i-th kind of ion, mol/L;

z_iThe valence mumber of i-th kind of ion.

Result judges: SI > 0, has scaling tendency; SI=0, critical state; SI < 0, without scaling tendency

2. Ryznar index of stability method

CaCO₃The Ryznar index of stability method of Scaling Tendency Prediction is calculated according to formula (4):

SAI=2 (K+p [Ca]+pAlK)-pH(4)

The meaning of each parameter and calculation cotype (4) in formula.

Result judges: SAI < 3.7, serious scale; 3.7 < SAI < 6, slight fouling; SAI=6, critical state; 6 < SAI < 7.5, mild corrosion; SAI > 7.5, heavy corrosion.

Simulated formation water: under 60 DEG C of conditions, the result of calculation according to Davis-Stiff saturation index method, SI index is 1.9975; According to Ryznar index of stability method result of calculation, SAI index is 4.9050.

Embodiment 1

A kind of organic base/surfactant binary composite oil-displacing system, raw material components is as follows by weight percentage:

Petroleum sulfonate 0.20%, ethanolamine 0.15%, ethylenediamine 0.05%, surplus 5000mg/L sodium-chloride water solution.

Preparation method:

Take each component by proportioning, under room temperature, sodium chloride is added in water and stirs, then add petroleum sulfonate, ethanolamine and ethylenediamine at normal temperatures, stir, obtain organic base/surfactant binary composite oil-displacing system.

Gained oil displacement system test case: the oil water interfacial tension recorded under 60 DEG C of conditions is 8.86 �� 10^-5MN/m, the petroleum sulfonate static adsorbance on oil-sand surface is 0.66mg/g.

Experimental example 1

Organic base/surfactant binary composite oil-displacing system the solution property of different salinities measures, and described organic base/surfactant binary composite oil-displacing system raw material components by weight percentage is as follows:

Petroleum sulfonate 0.20%, ethanolamine 0.15%, ethylenediamine 0.05%, excess water.

Concrete steps:

Take each component by proportioning, respectively different amounts of sodium chloride, calcium chloride are added to deionized water for stirring uniformly under room temperature, join the solution containing sodium chloride and the different salinities of calcium chloride. Chlorine in Solution na concn respectively 500mg/L, 1000mg/L, 500mg/L, 5000mg/L, 10000mg/L, 20000mg/L, 30000mg/L, 50000mg/L, 60000mg/L, calcium chloride concentration is 50mg/L, 100mg/L, 200mg/L, 400mg/L, 600mg/L, 800mg/L respectively, then at normal temperatures petroleum sulfonate, ethanolamine, ethylenediamine are separately added in proportion in the solution of different salinity, stir, obtain organic base/surfactant binary composite oil-displacing system when different salinity.

Gained oil displacement system, at 60 DEG C, surveys oil water interfacial tension value when different salinity, oil water interfacial tension value is down to 10^-3The highest NaCl concentration during mN/m is 50000mg L^-1, the highest CaCl₂Concentration 600mg L^-1��

Embodiment 2

A kind of organic base/surfactant binary composite oil-displacing system, raw material components is as follows by weight percentage:

Petroleum sulfonate 0.30%, ethanolamine 0.15%, ethylenediamine 0.05%, excess water.

Preparation method:

Take each component by proportioning, under room temperature, petroleum sulfonate, ethanolamine, ethylenediamine are proportionally added in clear water, stir, obtain organic base/surfactant binary composite oil-displacing system.

Gained oil displacement system is at 60 DEG C, and the petroleum sulfonate static adsorbance on oil-sand surface is 1.07mg/g, and oil water interfacial tension is 1.66 �� 10^-4mN/m��

Comparative example 1

Petroleum sulfonate 0.30%, excess water.

Gained oil displacement system is at 60 DEG C, and the petroleum sulfonate static adsorbance on oil-sand surface is 1.42mg/g.

By comparative example 2 and comparative example 1, the petroleum sulfonate adsorbance of embodiment 2 reduces by 24.6%.

Embodiment 3

A kind of organic base/surfactant binary composite oil-displacing system, raw material components is as follows by weight percentage:

Petroleum sulfonate 0.30%, ethanolamine 0.15%, ethylenediamine 0.05%, surplus simulated formation water.

Preparation method is with embodiment 1.

Gained oil displacement system at 60 DEG C, the result of calculation according to Davis-Stiff saturation index method, SI index is 0.6374; According to Ryznar index of stability method result of calculation, SAI index is 6.6253. Oil water interfacial tension is 5.73 �� 10^-5MN/m, the petroleum sulfonate static adsorbance on oil-sand surface is 1.05mg/g.

Embodiment 4

A kind of organic base/surfactant binary composite oil-displacing system, raw material components is as follows by weight percentage:

Petroleum sulfonate 0.10%, ethanolamine 0.1%, ethylenediamine 0.05%, excess water.

Preparation method is with embodiment 1.

Gained oil displacement system test case: the oil water interfacial tension recorded under 80 DEG C of conditions is 7.06 �� 10^-3MN/m, the petroleum sulfonate static adsorbance on oil-sand surface is 1.01mg/g.

Embodiment 5

A kind of organic base/surfactant binary composite oil-displacing system, raw material components is as follows by weight percentage:

Petroleum sulfonate 0.30%, ethanolamine 0.15%, ethylenediamine 0.075%, excess water.

Preparation method is with embodiment 1.

Gained oil displacement system test case: the oil water interfacial tension recorded under 80 DEG C of conditions is 1.66m �� 10^-4MN/m, the petroleum sulfonate static adsorbance on oil-sand surface is 0.93mg/g.

Embodiment 6

A kind of organic base/surfactant binary composite oil-displacing system, raw material components is as follows by weight percentage:

Petroleum sulfonate 0.20%, ethanolamine 0.15%, ethylenediamine 0.075%, excess water.

Preparation method is with embodiment 1.

Gained oil displacement system test case: the oil water interfacial tension recorded under 80 DEG C of conditions is 7.06m �� 10^-4MN/m, the petroleum sulfonate static adsorbance on oil-sand surface is 0.98mg/g.

Comparative example 2

Petroleum sulfonate 0.30%, sodium carbonate 0.15%, sodium bicarbonate 0.05%, excess water.

Gained oil displacement system test case: the oil water interfacial tension recorded under 60 DEG C of conditions is 1.66 �� 10^-4MN/m, the petroleum sulfonate static adsorbance on oil-sand surface is 1.26mg/g.

Comparative example 3

Petroleum sulfonate 0.30%, sodium carbonate 0.15%, sodium bicarbonate 0.05%, excess water.

Each component is taken by proportioning, respectively by different amounts of sodium chloride under room temperature, calcium chloride is added in appropriate amount of deionized water and stirs, the concentration of sodium chloride solution being configured to respectively 500mg/L, 1000mg/L, 500mg/L, 5000mg/L, 10000mg/L, 20000mg/L, 30000mg/L, 50000mg/L, 60000mg/L, calcium chloride solution concentration is 50mg/L respectively, 100mg/L, 200mg/L, 400mg/L, 600mg/L, 800mg/L, then at normal temperatures by petroleum sulfonate, sodium carbonate, sodium bicarbonate is separately added in the solution of different salinity in proportion, stir, obtain organic base/surfactant binary composite oil-displacing system when different salinity.

Gained oil displacement system, at 60 DEG C, surveys oil water interfacial tension value when different salinity, oil water interfacial tension value is down to 10^-3The highest NaCl concentration during mN/m is 30000mg L^-1, the highest CaCl₂Concentration 200mg L^-1��

Comparative example 4

Petroleum sulfonate 0.20%, sodium carbonate 0.15%, sodium bicarbonate 0.05%, excess water.

Gained oil displacement system is at 60 DEG C, and oil water interfacial tension is 5.73 �� 10^-3MN/m, the petroleum sulfonate static adsorbance on oil-sand surface is 0.87mg/g.

Comparative example 5

Petroleum sulfonate 0.40%, sodium hydroxide 0.15%, surplus simulated formation water.

Gained oil displacement system under 60 DEG C of conditions, the result of calculation according to Davis-Stiff saturation index method, SI index is 3.5028; According to Ryznar index of stability method result of calculation, SAI index is 4.1560. Oil water interfacial tension is 3.94 �� 10^-4MN/m, the petroleum sulfonate static adsorbance on oil-sand surface is 1.11mg/g.

Experimental example 2

Organic base/surfactant binary the composite oil-displacing system of embodiment 1 preparation, Oil Displacing Capacity is tested.

Filling fill out sand tube with 80��120 order quartz sands and make the simulation core of certain permeability, then saturation simulation formation water 10PV(PV is voidage), recording fill out sand tube permeability is 571 �� 10^-3��m².The saturated crude oil of fill out sand tube rock core, aging 24h at 60 DEG C, then simulated formation water carries out water drive, reaches 98% to fill out sand tube exit Produced Liquid moisture content, and now waterflood recovery efficiency factor is 51.2%. Injecting the oil displacement system solution of 0.40PV embodiment 1 gained, then proceed to sequent water flooding to the moisture content exporting Produced Liquid and reach 98%, calculating overall recovery factor is 70.8%, and gained oil displacement system improves recovery ratio amplitude and reaches 19.6%.

Experimental example 3

The oil displacement system of comparative example 4 preparation, Oil Displacing Capacity is tested.

Filling fill out sand tube with 80��120 order quartz sands and make the simulation core of certain permeability, then saturation simulation formation water 10PV(PV is pore volume), recording fill out sand tube permeability is 611 �� 10^-3��m². The saturated crude oil of fill out sand tube rock core, aging 24h at 60 DEG C, then simulated formation water carries out water drive, reaches 98% to fill out sand tube exit Produced Liquid moisture content, and now waterflood recovery efficiency factor is 43.9%. Injecting the oil displacement system solution of 0.40PV comparative example 4 gained, then proceed to sequent water flooding to the moisture content exporting Produced Liquid and reach 98%, calculating overall recovery factor is 59.5%, and gained oil displacement system improves recovery ratio amplitude 15.6%.

Claims (6)

1. organic base/surfactant binary composite oil-displacing system, it is characterised in that raw material components is as follows by weight percentage:

Petroleum sulfonate 0.10 ~ 0.30%, ethanolamine 0.10 ~ 0.15%, ethylenediamine 0.05 ~ 0.075%, sodium chloride 0.5 ~ 2%, excess water.

2. organic base according to claim 1/surfactant binary composite oil-displacing system, it is characterised in that raw material components is as follows by weight percentage:

Petroleum sulfonate 0.2 ~ 0.3%, ethanolamine 0.10 ~ 0.15%, ethylenediamine 0.05 ~ 0.06%, sodium chloride 0.5 ~ 2%, excess water.

3. organic base according to claim 1/surfactant binary composite oil-displacing system, it is characterised in that raw material components is as follows by weight percentage:

Petroleum sulfonate 0.20%, ethanolamine 0.15%, ethylenediamine 0.05%, sodium chloride 0.5 ~ 2%, excess water.

4. organic base according to claim 1/surfactant binary composite oil-displacing system, it is characterised in that raw material components is as follows by weight percentage:

Petroleum sulfonate 0.2 ~ 0.3%, ethanolamine 0.10 ~ 0.15%, ethylenediamine 0.05 ~ 0.075%, sodium chloride 0.5 ~ 2%, excess water.

5. a preparation method for the organic base described in claim 4/surfactant binary composite oil-displacing system, step is as follows:

Take each component by proportioning, under room temperature, sodium chloride is added in water and stirs, then add petroleum sulfonate, ethanolamine and ethylenediamine at normal temperatures, stir, obtain organic base/surfactant binary composite oil-displacing system.

6. the organic base described in claim 1-4/surfactant binary composite oil-displacing system is applied to the tertiary oil recovery process of oil exploitation.