CN1426507A - Solid-stabilized water-in-oil emulsion and method for using same - Google Patents

Abstract

A method for enhancing the stability of a solids-stabilized water-in-oil emulsion by pretreating the oil prior to emulsification. The pretreatment step can be accomplished by adding dilute acid to the oil, adding a lignosulfonate additive to the oil, sulfonating the oil, thermally oxidizing the oil, thermally treating the oil in an inert environment, and combinations thereof. The emulsion can be used in enhanced oil recovery methods, including using the emulsion as a drive fluid to displace hydrocarbons in a subterranean formation, and using the emulsion as a barrier fluid for diverting flow of fluids in the formation.

Description

Solid-stabilized water-in-oil emulsion and application process thereof

Invention field

The present invention relates to be used to improve the solid-stabilized water-in-oil emulsion of oil extraction amount.More particularly, by before emulsification, the pretreated method of oil having been strengthened the stability of solid-stabilized water-in-oil emulsion.Pre-treatment step can realize by following method: add diluted acid in described oil, add lignosulphonates in described oil, the described oil of sulfonation, the described oil of heat treatment in inert environments, the described oil of thermal oxide, and combination.The emulsion of improving or can be used as displacing fluid comes hydrocarbon in the displacement subterranean strata, or as stopping that liquid makes moving the turning to of hydrocarbon stream in the rock stratum.

Background of invention

People know, and are elevated to this degree at the cost of primary recovery, so that after the cost height that further recovers the oil, the oil of residual significant percentage still in the subterranean strata.Usually, in the primary recovery process, only reclaimed the crude oil in original place 1/5～1/3.At this moment, the methods that can utilize some yields (EOR) that increase oil are with the further producing oil of mode cheaply.These methods are based on pressurizeing again or keeping oil pressure and/or flowability.

For example, the water filling of oil reservoir is a kind of common method that is used to increase in industry from the subterranean strata oil production.Water filling relates to injects water oil reservoir (general by injecting well) simply.The effect of water is the oil in the oil reservoir of displacement producing well.Yet when taking water filling to come the heavy oil of thickness in the displacement oil reservoir, this method efficient is low, because the flowability of oil mobile much smaller than water.Water passes the rock stratum rapidly and arrives producing well, walks around most of oil and remaining oil can not get reclaiming.For example, at Canadian Saskatchewan, according to reports, the former oil mass of primary recovery only accounts for 2～8% of local former oil mass, again 2～5% of a water filling production original place oil mass.Therefore, need make water more viscous, perhaps utilize other not pass the displacing fluid of oil.Owing to need a large amount of displacing fluids,, and under the flox condition of rock stratum, be stable so it must be cheap.When the flowability of displacing fluid was significantly smaller than oil mobile, the displacement of oil was just the most effective, so what need most is a kind of method that produces the lazy flow displacing fluid in mode cheaply.

The exploitation of oil is influenced by the jumpy of rock permeability also, and for example, the high osmosis of injecting between well and the producing well " lost-circulation zone " makes most of displacing fluid that injects pass producing well rapidly, and the oil phase in remaining other layer is not to reclaiming.The low-cost fluid (from injecting well or producing well) that needs to be injected into such lost-circulation zone to be reducing fluid mobility, so, pressure energy is turned to and oil in the adjacent more low permeability layer of displacement.

In some rock stratum, the yield of oil can should be bores the air inlet body downwards or to epicone water inlet and reduce to the interval of produce oil.Therefore, need a kind of injectant cheaply, it can be used to set up horizontal " cushion pad " of lazy flow fluid and enter vertical barrier layer between the origin layer as oil-producing formation and awl.Vertical awl that such lazy flow fluid can hinder gas or water advances, so improve oil production.

For the oil of appropriate thickness-promptly, viscosity be about 20～100 centipoises (cP) those-utilize water-soluble polymer (for example, polyacrylamide or xanthan gum) to increase the viscosity of water of injection and the oil of displacement rock stratum.For example, in the Sleepy of Nebraska Hollow oil field, polyacrylamide is added in the water that is used for to the water filling of 24cP oil.Also utilize polyacrylamide to increase the water viscosity that is used for to the oily water filling of 40cP in the Chateaurenard oil field of France.In this way, polymer is water-soluble, increase its viscosity.

Though water-soluble polymer can be used to realize to favourable flow of low thickness to the oily water filling of middle thickness, common, they can not be used for economically realizing that more viscous oil-promptly, viscosity are about the favourable mobile displacement of 100cP or bigger those oil.These oil are thickness so, thus realize favourable flow normally more uneconomic than the amount of required polymer.In addition, it be known to those skilled in the art that the water-soluble polymer surface from displacement water desorption to formation rock usually, it is held back and make it can not be effectively to the water tackify.Cause the forfeiture of mobile control like this, the oil exploitation of difference, and high polymer expense.For these reasons, adopting polymer displacement of reservoir oil to exploit viscosity is impracticable greater than the oil of 100cP usually technically or economically.Moreover the characteristic of a lot of polymer is common in the adverse effect of the ion concentration of the dissolving in the rock stratum, limits their application and/or efficient.

People have proposed water and the thick method of dripping emulsion as the displacing fluid of producing thickness of oil, the flowability control that this displacing fluid can remain valid and the oil of displacement thickness suitably simultaneously.For example, people have estimated Water-In-Oil and oil-in-water slightly drips emulsion is improved the oil of thickness as displacing fluid exploitation.Such emulsion is by toward producing from interpolation NaOH in the Canada and the sour crudes of Venezuela.The soap-film that produces by the acidic hydrocarbon component in the NaOH saponification crude oil makes described emulsion-stabilizing.These soap-films have reduced oil/water termination tension force, play surfactant and make described water-in-oil emulsion stable.Therefore, people know, and the stability of such emulsion roughly depends on and is used for producing the application of soap-film with the NaOH (that is caustic alkali) that reduces oil/water termination tension force.

For utilize caustic alkali produce the various researchs of this class emulsion verified technical feasibility.Yet the practical application of this oil production method is subjected to the restriction of following factors: caustic alkali expensive, soap-film may be attracted on the formation rock, cause the decomposition gradually of emulsion, and emulsion viscosity is to the sensitiveness of the minor variations of water salinity and water content.For example, because the water of the solids of a lot of dissolvings is contained on most of stratum, so, need the emulsion of fresh water or distilled water can not reach the potential of design usually, because in actual formation, be difficult to realize and keep low like this salinity condition.May be from the rock dissolution ionic species, and the fresh water that injects may mix with the residual water of higher salinity, causes the decomposition of low-tension stabilized emulsion.

Taked the whole bag of tricks optionally to reduce the permeability (being commonly called " section modification ") of the saturating property of technology middle and high infiltration " lost-circulation zone " already.Be injected into the conventional agent that oil reservoir realizes that the permeability of contact zone reduces and comprise polymer gel or crosslinked aldehydes.Polymer gel is being cross-linked to form by polymer (for example, polyacrylamide, xanthans, polyvinyl or lignosulphonates).Such gel is injected the rock stratum, and the cross-linking reaction there causes gelling and becomes harder, so reduce to flow through the permeability of treatment region.

In the great majority of these methods were used, the rock stratum district that is subject to processing influence was limited near the well because of reaction time of expense and gelling agent.In case handle suitably, gel is just more stable.This may be disadvantageous, because displacing fluid (for example, the water during water filling) is finally walked around stabilizing gel, has reduced its effect.If the section dressing agent can move through the rock stratum lentamente and stop up the new lost-circulation zone that produces, penetrate suitable distance from injecting well or producing well, just can look forward to better characteristic.

McKay is in U.S. Patent No. 5,350, discloses a kind of method of carrying out oil recovery by heating from the rock stratum and producing heavy oil or pitch in 014.McKay has described and a kind ofly has been higher than minimum temperature (T by the temperature profile that keeps swept zone carefully _c) method of producing oil or the pitch be the O/w emulsion form.If the temperature of described O/w emulsion is kept above this minimum temperature, emulsion can flow through the porosity subterranean strata and accumulate in producing well.McKay has described the another embodiment of his invention, wherein, a kind of O/w emulsion introducing rock stratum is remained below the temperature of described minimum temperature.This metastable emulsion is used to form the barrier layer to block the lost-circulation zone of poor-water in the rock stratum that produces by geothermal method (comprising the control of the vertical coning of water).Yet the method that McKay describes need be controlled the temperature in the district of rock stratum carefully, so, only be applicable to that geothermal method recovers the oil.As a result, the method for McKay description can not be used for non-heating power (being called " cold flow ") recovery heavy oil.

Disclose a kind of new method in the recent period, it is used novel solid thing stabilized emulsion and improves oil production.United States Patent (USP) 5,927,404 have described a kind of method, and it is used novel solid thing stabilized emulsion and comes the displacement hydrocarbon to improve oil production as displacing fluid.United States Patent (USP) 5,855,243 have applied for a kind of similar approach of applying solid thing stabilized emulsion, its viscosity has reduced by the gas that adds as the displacement fluid.United States Patent (USP) 5,910,467 have applied for United States Patent (USP) 5,855, the novel solid thing stabilized emulsion of describing in 243.United States Patent (USP) 6,068,054 has described a kind of novel solid thing stabilized emulsion of using as stopping that liquid makes the method for the fluid flow divert in the rock stratum.

Preparation has, and the most solid-stabilized emulsion of suitable performance is successfully to utilize emulsion to improve the key of oil production.Stability that two important performances are emulsions and its rheological characteristic.Solid-stabilized emulsion should be a stable storage, that is, this emulsion should keep stable emulsion and not have water or oil to separate out when leaving standstill.In addition, this emulsion should be stable under the flox condition that flows through porous medium (that is, in subterranean strata).The rheological behavior of emulsion also is important.For example, the EOR method that can use emulsion comprises, with emulsion as displacing fluid or stop that liquid injects subterranean strata.Therefore, this emulsion should have and can and play displacing fluid or stop liquid for the suitableeest viscosity of injecting.When implementing EOR (when particularly utilizing emulsion), the rheological characteristic of emulsion and the rheological characteristic of the oilbearing stratum of exploitation are mated as displacing fluid.When the ratio of viscosities of displacing fluid is will be by the oil viscosity of displacement bigger, utilize displacing fluid displacement oil generally more effective.Except solid-stabilized emulsion being provided the stability the solid-stabilized emulsion of the wide region rheological characteristic that the rheological characteristic that the present invention described herein can make the user prepare the oil that has and will exploit is mated.

Owing to obtain water and oil easily in most of production scenes, so water-in-oil emulsion is the good selection of the solid-stabilized emulsion of preparation EOR.Some oil have required chemical composition and the physical property of solid-stabilized water-in-oil emulsion that preparation contains the solids of wide region.The solids that adds interacts with the component (that is, polarity thing and asphalitine) of oil, causes them to increase as the effect of surfactant.This interaction is specific for the solids classification with the composition that adds their oil.

But if oil does not contain the polarity thing and the asphalitine compound of concentration right type and enough, the interpolation of solids is exactly invalid, because solids is not played the function of stabilizer of oil-water interface by modification suitably and suitably.Therefore, some oil does not form stable solid-stabilized water-in-oil emulsion with any solids, perhaps, some oil can with the solids of some type (for example, silica) form stable emulsion, but can not form same stable emulsion with the solids (for example, clay and ickings) of other type.The technology of preamble citation has been enlightened, and asphalitine or nonpolar hydrocarbon can be added in these oil to improve the ability that they form stable emulsion.United States Patent (USP) 5,855,243, the 7 hurdles, 6～10 row; United States Patent (USP) 5,927,404 the 6th hurdles, 44～47 row; United States Patent (USP) 5,910,467 the 7th hurdles, 3～6 row.Yet success always of this interpolation is because the incompatibility between the asphalitine of some oil ingredient and interpolation and the polarity thing can cause being separated or repel the compound of interpolation.These situations have limited the scope of invention disclosed in the above-mentioned United States Patent (USP).

For expanded scope and improve United States Patent (USP) 5,927,404,5,855,243,5, the solid-stabilized emulsion of describing in 910,467,6,068,054, need a kind of such method, it suitably improves oil component, so its responds the interpolation of solids and prepares stable water-in-oil emulsion.The present invention has satisfied this requirement.

Summary of the invention

By the present invention, a kind of method that strengthens the stability of solid-stabilized water-in-oil emulsion is provided, described method comprises, this step of at least a portion of preliminary treatment oil before emulsification.

In one embodiment of the invention, described oily pre-treatment step comprises, goes in emulsification and adds rare organic acid or inorganic acid in oily at least a portion.

In another embodiment of the invention, described oily pre-treatment step comprises, goes in emulsification and adds the lignosulphonic acid salt additives in oily at least a portion.

In another embodiment of the present invention, described oily pre-treatment step comprises, at least a portion of sulfonated oil before emulsification.

In another embodiment of the present invention, described oily pre-treatment step comprises, before emulsification, and at least a portion of heat treating oil in inert environments.

In another embodiment of the present invention, described oily pre-treatment step comprises, at least a portion of thermal oxide oil before emulsification.

Also can use the combination of these embodiments.Further disclose a kind of method from the subterranean strata recovery of hydrocarbons, it comprises:

A) prepare solid-stabilized water-in-oil emulsion with pretreated oil;

B) described solid-stabilized emulsion is contacted with the rock stratum, and

C) utilize described solid-stabilized emulsion from the rock stratum recovery of hydrocarbons.

Detailed description of the present invention

At US 5,927,404, summarized solid-stabilized water-in-oil emulsion among US 5,855,243 and the US 5,910,467.Such emulsion prepares by following method: ultramicrofine oil is combined with the miniaturization solid particle, mix with water until forming solid-stabilized water-in-oil emulsion again.

Disclosed such in the United States Patent (USP) that relates to as mentioned, solid particle should have certain physical character.Single particle diameter should be enough little and the enough surface areas that cover the inner droplets phase are provided.If emulsion will be used to the porosity subterranean strata, average grain diameter just should be less than the average diameter of pore throat in the porosity subterranean strata.The method of measuring average grain diameter has been described in the United States Patent (USP) of preamble citation.Described solid particle may spherical in shape or non-sphere.If spherical in shape, solid particle should preferably have about 5 microns or the average-size of minor diameter more, more preferably from about 2 microns or littler, and further preferred about 1 micron or littler, and 100 nanometers or littler most preferably from about.If solid particle is not spherical in shape, they should preferably have the average-size of about 200 square micron total surface areas, 20 square microns or littler more preferably from about, and further preferred about 10 square microns or littler, and most preferably be 1 square micron or littler.The oil phase of described solid particle emulsion under the condition of rock stratum and aqueous phase also must keep not dissolving.

The invention enables and can form stable solid-stabilized water-in-oil emulsion from oil, described oil lacks compound and the asphalitine compound that forms this stable desired suitable polarity of emulsion in other cases.Using method that United States Patent (USP) 5,927,404,5,855,243 and 5,910,467 describes prepares the required oil of stable emulsion and must contain asphalitine, nonpolar hydrocarbon or the polar resin of q.s and stabilization of solid-particle-oil phase mutual effect.But, as mentioned above, feasible these compounds that can form required enough types of stable solid-stabilized emulsion and amount of some oil.By the present invention, described oily preliminary treatment is promoted to form stable solid-stabilized water-in-oil emulsion.

The oil that is used for preparing solid-stabilized emulsion of the present invention can be the oil of any classification or composition, and it includes but not limited to: crude oil, refined oil, alloyd oil, chemically treated oil, or its mixture.Crude oil is unpurified liquid petroleum, and refined oil is by the crude oil behind the purifying that (for example, removed sulphur) someway.Crude oil is to be used to implement preferred oil of the present invention, and more preferably, described crude oil is to exploit from the rock stratum that will use emulsion.The crude oil of exploitation may comprise stratum gas, perhaps formation water, the perhaps salt solution that mixes with oil.Preferably, with the dehydration of crude oil, but, mixture, stratum gas and/or the formation brine of oil also can be used for the present invention before processing.

Preferably, use formation water and prepare emulsion, but, also can utilize fresh water and regulate ion concentration as required and help under the condition of rock stratum, to stablize described emulsion.

Solid-stabilized water-in-oil emulsion of the present invention is applicable to the application of the various raising oil productions that this area is usually known, comprises but is not restrictive, utilizes such emulsion (a) to come hydrocarbon in the displacement subterranean strata as displacing fluid; (b) in using, " section modification " inject high osmosis rock stratum district to improve EOR characteristic subsequently; And (c) form effective transverse barriers layer, for example, form the barrier layer of vertically flowing of water or gas water or gas with the oil-producing region that reduces awl oil-feed well.

The physical property and the chemical property characteristic of three kinds of different classes of crude oil (claiming that they are crude oil #1, crude oil #2 and crude oil #3) have been listed in the attached table 1.As United States Patent (USP) 5,927,404,5,855,243 and 5,910, described in 467, crude oil #1 and crude oil #3 have the character of crude oil bag aqueous emulsion of solids that can form stable interpolation.But, using identical method, crude oil #2 can not form stable solid-stabilized water-in-oil emulsion.

Table 1

The Wu Lixingzhi ﹠amp of crude oil; Chemical property Character Crude oil #1 Crude oil #2 Crude oil #3Api gravity 16.8 15.5 8.6 viscosity (cP) 4,800 2,400 384,616 (25 ℃, 1sec ^-1) interfacial tension (dynes per centimeter) 2.2 33.7 seawater asphalitines (N.heptane insolubles (wt%)) 0.1 ± 0.02 2.6 13.7 toluene equivalent 0.0 14 20 sulphur (wt%) 0.12 0.98 3.89 nitrogen (wt.1%) 0.18 0.07 0.19 Cut (Vol.%)IC5/175 °F of T Lt.Naph--38.04 42.41 38.81049 °F+residual oil of 9.88 14.27 9.5650/1049 °F of PGO of 7.83 12.39 4.8530/650 °F of Lt.Gasoil of 1.80 3.22 1.0375/530 °F of kerosene of 250/375 °F of Hvy.Naph of 0.6 0.2175/250 °F of Med.Naph--1.3--42.45 25.80 45.7HPLC fraction (wt%)Reclaiming quality 83.8 56.6 66.99 saturates 41.7 28.51 17.671-encircles 7.5 11.40 10.072-and encircles 7.0 9.85 12.893-and encircle 7.6 7.96 10.154-and encircle 13.0 16.06 20.93 polarity things, 23.2 26.23 28.29 aromaticities 17.1 20.27 22.37The Iatrascan dataSaturate 27.2 19.4 6.4 aromatic hydrocarbons 44.7 44.7 42.5NSO ' s 19.0 30.1 29.0 asphalitines, (pentane is insoluble), (wt%) 8.9 5.8 22.1 aromatic hydrocarbons/saturate 1.64 2.3 6.66NSO ' s/Asph, (pentane is insoluble) 2.13 5.19 1.31TAN 6.2 6.2 3.13HPLC measures The distribution of acidic fraction (%)250MW 8.5 47.2 22.4300MW 23.9 24.5 20.7425MW 30.5 15.9 20.4600MW 20.4 7.0 14.6750MW 16.7 5.4 21.7 acidic aromatic degree 8.6 17.2 19.0Metal (ppm)Ca 30～160 4.22 1.83Na 10.4～15.5 1.51 11.2V 0.16～0.31 69.6 434Ni 9.05～13.0 65.6 102

Crude oil #2 is different with crude oil #1 and #3 aspect following: 1. crude oil #2 has higher resin/asphalitine ratio 2. crude oil #2 and has higher low-molecular-weight aphthenic acids ratio, and 3. crude oil #2 compare with crude oil #1 and have lower calcium and sodium content.These differences have been enlightened:

1. surface reactive material (that is, asphalitine and acid/resin, they are key components of emulsification) is not easy to be used to the water droplet among the stabilized crude (oil) #2, and

2. be the potential approach that improves stability of emulsion for the physical property that changes oil and chemical compound and to the preliminary treatment of oil.

Therefore, the invention describes a kind of method that oily preliminary treatment is increased the stability of solid-stabilized emulsion.Now several embodiments of the present invention will be described.Those of ordinary skills can understand, can be with one embodiment of the invention and one or more other embodiment applied in any combination of the present invention, and they can provide collaborative effect aspect the described solid-stabilized emulsion stablizing. With diluted acid to oily preliminary treatment

A kind ofly with the method that improves its and form the ability of stable solid-stabilized water-in-oil emulsion be to oily preliminary treatment, before emulsification with rare inorganic acid or organic acid to oily preliminary treatment.This acid preliminary treatment causes the modification to oil and solids surface.(1) component that contains basic nitrogen in the oil is converted into corresponding inorganic or acylate.These salt itself have bigger surface-active than the component that contains basic nitrogen, so, help to improve the stability of solid-stabilized water-in-oil emulsion; (2) if described oil comprises aphthenic acids, stronger inorganic or organic acid is replaced and is contained the compound aphthenic acids of alkaline nitrogen compound, in providing higher surface-active; (3) proton-effect of described acid is that the site of described solids surface band anionic charge is protonated to improve it and the interaction of the surface active composition of oil (preexist in the oil or produce by acid treatment); (4) if described oil comprises calcium and aphthenic acids, inorganic or organic acid just can be replaced calcium and be discharged described aphthenic acids, and their surface-active is bigger than calcium naphthenate. Utilize dilute acid pretreatment to prepare solid-stabilized water-in-oil emulsion

In order to prepare this embodiment of the present invention, go to the rare inorganic or organic acid of interpolation in the described oil in emulsification.Can before sour preliminary treatment or afterwards, in described oil, add solid particle, but preferred elder generation adds solids in described oil, again with the above-mentioned oil that contains solids of sour preliminary treatment.After sour preliminary treatment and solids added, by with little aliquot or add water continuously and mix and form solid-stabilized emulsion, preferably mixing to reach with the speed of 1000～12000rpm was enough to make water to be dispersed in time in the oil-continuous phase as little water droplet.Preferably making the water concentration in the described water-in-oil emulsion is 40～80%, more preferably 50～65%, and most preferably 60%.

Preferably mixed about 5～10 minutes down when adding acid in the oil at 25～40 ℃.Preferred acid treatment ratio is 8～30,000ppm.Described diluted acid can be inorganic acid, organic acid, mixtures of mineral acids, organic acid mixture, or inorganic acid and organic acid mixture.Preferred inorganic acid is hydrochloric acid and sulfuric acid.But, also can use other inorganic acid, include but not limited to: perchloric acid, phosphoric acid and nitric acid.Preferred organic acid is an acetate.But, also can use other organic acid, include but not limited to: right-toluenesulfonic acid, alkyl toluene sulfonic acid, one, two and trialkyl phosphoric acid, organic monobasic or dicarboxylic acids (for example, formic acid), C3～C16 organic carboxyl acid, butanedioic acid, and petroleum naphthenic acid.Also can add petroleum naphthenic acid to increase the surface-active in the oil, perhaps can will contain the oil of high aphthenic acids and significant oily fusion and the surface-active of increase is provided.

Described solid particle is preferably hydrophobic.Find that a kind of hydrophobic silica of selling with trade name Aerosil  R972 (product of DeGussa Corp.) is effective solid granulate material of some different oil.Also can use other hydrophobicity (or lipophile) solid, for example, dispersion with glossy wet swell soil, kaolin, organic soil or carbenes matter solid.It is 0.05～0.25wt% based on the weight of oil that solids is preferably handled ratio.

After the emulsion preparation, can reach the pH that is enough to raise by the weak base aqueous solution that in emulsion, adds amount of calculation and regulate its pH to the time of desired level.Wish to regulate the scope of emulsion pH to 5～7.Yet, regulate pH and choose wantonly, make oil reservoir rock buffering emulsion to oil reservoir basicity because need in some cases to inject acid emulsion.

Ammonium hydroxide is the preferred alkali that pH regulates.Stronger alkali (for example, NaOH, potassium hydroxide and calcium oxide) has side effect to stability of emulsion.Possible explanation about this effect is that highly basic tends to transform emulsion (that is, transform water-in-oil emulsion and become O/w emulsion).The present invention does not wish such conversion.

Except the stability that increases solid-stabilized water-in-oil emulsion, described sour preprocess method causes emulsion to have the lower viscosity of emulsion that produces than not carrying out sour preliminary treatment.The syringeability that reduces to help to strengthen emulsion of this viscosity.So we can measure the viscosity that reduces described solid-stabilized emulsion by suitably regulating pretreated acid.The ability of this control emulsion viscosity makes the user rheological behavior of emulsion and the rheological behavior of oil to be exploited mates the most rightly (particularly when the EOR method of employing particular type).As United States Patent (USP) 5,855,243 and 5,910, shown in 467, can add the viscosity of gas with further reduction emulsion.

Another embodiment of the invention is, adding before water and the emulsification, uses slip-stream or main batch (the master batch) of dilute acid pretreatment oil as described above, subsequently, described slip-stream mixed with oily master stream.The preferably untreated crude oil in this oily master stream, but, it can be any oil, comprises processed to strengthen ability that its forms stable emulsion or processed and optimize the oil of its rheological characteristic.If adopt this slip-stream method, just regulate slip-stream and handle the required solids and the amount of diluted acid according to acquisition required amount in the emulsion that forms. Embodiment:

Carried out following test and set forth sour preliminary treatment improving the effect that oil forms the ability of stable solid-stabilized water-in-oil emulsion.These embodiment concentrate on crude oil #2 and another kind of crude oil (crude oil #4).By United States Patent (USP) 5,927, the method for describing in 404,5,855,243 and 5,910,467, these crude oil all do not form stable solid-stabilized emulsion.In table 2, provided the physical property of crude oil #4.These tests have been illustrated, and sour preliminary treatment has strengthened the ability of the stable solid-stabilized emulsion of oily formation.In 1.2～7.0 pH scope, formed stable emulsion, and in these emulsions fusion the water of 72wt% at the most.

Table 2

The Wu Lixingzhi ﹠amp of crude oil; Chemical property Character Crude oil #4Api gravity 17.2 viscosity (cP) 8500 (25 ℃, 1sec ^-1) asphalitine (N.heptane insolubles (wt%)) 0.1 asphalitine (cyclohexane insoluble matter (wt.%)) 3.25 toluene equivalents, 0.0 sulphur (wt%), 0.12 nitrogen (wt.%) 0.26 Cut (Vol.%)36.481049 °F+residual oil of IC5/175 °F of Lt.Naph--175/250 °F of Med.Naph--8.67650/1049 °F of PGO of 6.09530/650 °F of Lt.Gasoil of 0.03375/530 °F of kerosene of 250/375 °F of Hvy.Naph 48.73HPLC fraction (wt%)Reclaim quality 84.4 saturate 43.31-ring 7.62-ring 6.83-ring 7.54-and encircle 12.6 polarity things, 22.2 aromaticities 15.6The Iatroscan dataSaturate 35.4 aromatic hydrocarbons 39.8NSO ' s 15.4 asphalitines 9.4 aromatic hydrocarbons/saturate 1.13NSO ' s/Asph. 1.64TAN 5.4HPLC measuresThe distribution of acidic fraction (%) ^*250～300MW, 15.4300～425MW, 14.7425～600MW, 27.1600～750MW 21.5750+MW, 21.3 acidic aromatic degree 8.6 Metal (ppm)Ca 400～900Na 7.7～15.3V 0.2～0.9Ni 11.2～17.9Mn 13.1K 181～935Mg 1.1～25.2

In type testing, with 8～30, the processing ratio of 000ppm is added to rare inorganic acid or aqueous solutions of organic acids (0.35～35% concentration) in the oil, and utilizes Waring blender or Silverson homogenizer fully to mix 10 minutes.Add solid particle, then mix.The acid preliminary treatment is added water with little aliquot after finishing in oil under mixing, it causes solid-stabilized water-in-oil emulsion.

Experience following test by emulsion with the preparation of dilute acid solution preliminary treatment oil:

1. at 25 ℃ of bin stabilities of assigning 48 hours

2. optical microscopy and/or nuclear magnetic resonance (NMR) are measured water droplet size/Size Distribution

3. microcentrifugation test-emulsion is to centrifugal stability (described in appendix-1)

4. stability of emulsion-flow through sandpack column (having described this ultra micro percolation test in the appendix-1)

5. use Brookfield viscometer (awl (#51) and plated construction) 60 ℃ down 1.92～

384sec ^-1The shearing scope in measure the rheological characteristic of emulsion.

Provided result of the test in table 3～6 with hydrochloric acid and sulfuric acid preliminary treatment crude oil #2.Provided result in the table 7 with sulfuric acid and acetate preliminary treatment crude oil #4.

The hydrochloric acid preliminary treatment of embodiment 1. crude oil #2

Prepare 60/40 water-in-oil emulsion that contains 0.15wt% hydrophobic silica-Aerosil  R972 with crude oil #2, but sour preliminary treatment of no use.As shown in table 3, this solid-stabilized emulsion is a stable storage, and still, this emulsion is unstable in microcentrifugation and ultra micro percolation test, oozes out (%bbo) by high water (salt solution) and has confirmed this point.The drop diameter that disperses is in 1～10 micrometer range.

Then, tested the influence of hydrochloric acid preliminary treatment to the stability of solid-stabilized emulsion.Prepare 60/40 solid-stabilized water-in-oil emulsion with crude oil #2.But, in this embodiment, with 38, the ratio preliminary treatment oil of 000ppm then, adds 0.15wt%Aerosil  R972 with hydrochloric acid.The drop diameter that disperses is in 1～2 micrometer range.As shown in table 3, the hydrochloric acid preliminary treatment causes the enhancing of microcentrifugation and ultra micro diafiltration stability, so, having improved the stability of emulsion, the minimizing of water seepage discharge has shown this point in two tests.

Table 3

With hydrochloric acid preliminary treatment crude oil #2 preprocess method: with 38,000ppm HCl is added in the crude oil, with Waring blender mixing 10min.HCl crude oil solid particle is stored drop trace ultra micro

/ water (Aerosil  R972) the centrifugal diafiltration ppm of stable diameter (wt%) (2 days) (micron) (%bbo) (%bbo) 0 40,/60 0.15 stable 10～1 18 3538,000 40,/60 0.0 stable 10～1 0 2038,000 40,/60 0.15 stablize 2～1 0 538, and 000 33,/66 0.15 stable 2～1 0 4bbo ∷ use that salt solution (water) oozes out in the microcentrifugation test of Ottawa sand

Embodiment-2. sulfuric acid the preliminary treatment of crude oil #2

Prepare 60/40 water-in-oil emulsion that contains 0.15wt%Aerosil  R972 with crude oil #2, but sour preliminary treatment of no use.As shown in table 4, this emulsion (though being stable storage),, unstable in microcentrifugation and ultra micro percolation test.The drop diameter that disperses is in 1～10 micrometer range.

Prepare 60/40 crude oil bag aqueous emulsion with sulfuric acid preliminary treatment crude oil #2, but do not added solids.With the weight based on oil is the ratio interpolation sulfuric acid of 8750ppm.The emulsion that forms is very unstable in microcentrifugation and ultra micro percolation test.

Is that the ratio preliminary treatment crude oil #2 of 8750ppm has prepared 60/40 crude oil bag aqueous emulsion with sulfuric acid with the weight based on oil, has added 0.15wt%Aerosil  R972.As shown in table 4, this method causes stable emulsion.The drop diameter that disperses is in 1～2 micrometer range.The emulsion pH that forms is 1.2.The sulfuric acid preliminary treatment of oil causes the enhancing of microcentrifugation and ultra micro diafiltration stability, and the minimizing of being oozed out the amount of (%bbo) by water or salt solution has illustrated this point.

Having prepared 60/40 crude oil bag aqueous emulsion, that is, is the processing ratio preliminary treatment crude oil #2 of 8750ppm with sulfuric acid with the weight based on oil, then, adds 0.15wt% hydrophily silica-Aerosil  300 (product of DeGussa Corp.).This method does not provide stable water-in-oil emulsion, because the water that emulsion is oozed out in microcentrifugation and ultra micro percolation test has increased.The inferior characteristic of hydrophily silica-Aerosil  300 has been enlightened, and the hydrophobic solid thing is normally used dilute acid pretreatment, and to form stable emulsion required.

Table 4

With sulfuric acid preliminary treatment crude oil #2 preprocess method: with 8750ppm H ₂SO ₄Be added to crude oil Zhong ﹠amp; With Waring blender mixing 10min.H ₂SO ₄The oil solid particle is stored liquid-drop diameter trace ultra micro

/ water (Aerosil  R972) stable centrifugal diafiltration ppm (wt%) (2 days) (micron) is (%bbo) 0 40,/60 0.15 stable 10～1 18 358,750 40,/60 0.0 stablizing 10～1 20 918,750 40,/60 0.15 2～1 0 08,750 33,/66 0.15 stable 2～1 1 28,750 40,/60 0.10 stable 2～1 0 08,750 40,/60 0.075 stable 2～1 0 stable 0bbo ∷ and use that salt solution (water) oozes out in the ultra micro percolation test of Ottawa sand (%bbo)

Embodiment-3. increases the water content of the pretreated crude oil #2 of sulfuric acid

As shown in table 5, can be in the past by mixing the water of about 70wt% in the solid-stabilized water-in-oil emulsion with dilute sulfuric acid preliminary treatment crude oil #2 preparation.When being higher than the water of about 72wt%, observe the increase of water droplet size.When being higher than the water of about 80wt%, phase separation of emulsions is emulsion and excessive water.Rheometry is the result show, the viscosity of emulsion increases with the increase of water content in the emulsion.

Table 5

The effect % water that increases the water content of the pretreated crude oil #2 emulsion of sulfuric acid is stored micro-ultra micro liquid-drop diameter viscosity

The centrifugal diafiltration 35C of stability, 9.6s ^-1

(%bbo) (%bbo) (micron) 60 is 00＜2 15,40065.5 be 00＜2 15,88869.2 be 00＜2 20,15271.4 be 00＜2 27,85275 is 05＜2～5 26, and 21480 is 0 10＜2～1085 to be separated and to be Ru Ye ﹠amp; Excessive water remarks: solids: salt solution (water) oozes out sulfuric acid treatment ratio: 8750ppm in the ultra micro percolation test of 0.15wt%Aerosil  R972 silica bbo ∷ application Ottawa sand

Embodiment-4: the solid contents that reduces 60/40 crude oil #2 bag aqueous emulsion

As shown in table 6, prepared stable emulsion with hydrophobic silica-Aerosil  R972 (concentration is in 0.025wt%～0.15wt% scope).The viscosity of emulsion has reduced with the reduction of solid contents.

Table 6

The effect % solid particle that reduces the solid contents of the crude oil #2 emulsion that sulfuric acid treatment crosses is stored 35 ℃ of the stable centrifugal diafiltration diameters of micro-ultra micro drop viscosity (Aerosil  R972), 9.6s ^-1

(%bbo) (%bbo) (micron) 0.15 is 00＜2 154000.1 to be 00＜2 78640.075 to be 00＜2 75360.05 to be 00＜2 81920.025 to be 00＜2～5 6389 remarks: oil/water ratio=40/60bbo ∷ uses that salt solution (water) oozes out sulfuric acid treatment ratio: 8750ppm in the ultra micro percolation test of Ottawa sand

Embodiment-5: the sulfuric acid of crude oil #4 and acetate preliminary treatment

Similar to the result of crude oil #2, the sour preliminary treatment of crude oil #4 causes the enhancing of the solid-stabilized stability of emulsion that forms.Data in the table 7 show, are the ratio preliminary treatment crude oil #4 of 8750ppm with sulfuric acid with the weight based on oil, then, add 0.15wt%Aerosil  R972 and cause stable emulsion.

With 24, the processing ratio preliminary treatment crude oil #4 of 500ppm then, adds 0.15wt%Aerosil  R972 and also causes stable solid-stabilized 60/40 water-in-oil emulsion with acetate.Observe the lower of emulsion viscosity after the acetic acid treatment corresponding emulsion after than sulfuric acid treatment, illustrated that the character of acidulant can influence the viscosity of emulsion.

Table 7

The sour preliminary treatment acid % solid particle of crude oil #4 is stored micro-ultra micro drop viscosity

(the centrifugal diafiltration diameter 60C of Aerosil  stability, 9.6s ^-1

R972) (%bbo) (%bbo) (micron) nothing 0.15 is that 09＜2～10 5240 sulfuric acid 0.15 are that 0 3.5＜2 2948 acetate 0.15 are 00＜2 4095 remarks: viscosity=164cP@60C of crude oil #4,9.6s ^-1Salt solution (water) oozes out the sulfuric acid treatment ratio in the ultra micro percolation test of bbo ∷ application Ottawa sand: 8750ppm acetic acid treatment ratio: 24, and 500ppm

Embodiment-6: the pH that regulates acid-treated emulsion

Two kinds of methods of producing water-in-oil emulsion in 5～7 preferred pH scope have been described:

A) with in the alkali of appropriate amount and the fat liquor of preformed acid treatment:

Adding before the water or be the preferable methods of increase emulsion pH afterwards with the pretreated oil of ammonium hydroxide neutralizing acid.Otherwise, with the instability that causes emulsion in NaOH or the calcium oxide with emulsion.As previously mentioned, the possible explanation about this effect is that ammonium hydroxide is than NaOH or the more weak alkali of calcium oxide.Highly basic tends to transform emulsion,, water-in-oil emulsion is converted into O/w emulsion that is.This conversion is that method of the present invention is undesirable.

B) reduce the level of the basic component of acid treatment ratio in the oil that is enough to just to neutralize:

The another kind of method that obtains the emulsion in 5～7 pH scope is, reduces the level of the basic component of acid treatment ratio in the oil that is enough to just to neutralize.The acid of using in this test is hydrochloric acid, sulfuric acid and acetate.For crude oil #2 and crude oil #4, it is 5.5～6.5 required emulsion that the acid treatment ratio of having found 8.7ppm is enough to produce pH.Provided emulsion property summary in the table 8 with 8.75ppm sulfuric acid preliminary treatment crude oil #4.

Table 8

By using 8.75ppm sulfuric acid preliminary treatment crude oil #4

The emulsion property summary of the water-in-oil emulsion of preparation Emulsion property:Crude oil: 40wt% water: 60wt% hydrophobic silica (R972): 0.15wt% water droplet size (average diameter): 6 microns bin stabilities:＞2 all centrifugal stability: 0% water oozes out the stability that diafiltration sees through Berea sand: 16% water oozes out viscosity: 3700cP@60C, 9.6sec ^-1PH:6.2

Embodiment-8: add gas and reduce the viscosity of water-in-oil emulsion

In the pretreated fat liquor of acid, add CO ₂Can reduce the viscosity of emulsion effectively.For testing from the emulsion of pretreated crude oil #2 of 8700ppm sulfuric acid and 0.15wt%Aerosil  R972 preparation.

The result who is shown in Table 9 has disclosed, and under 500psi pressure and corresponding reservoir temperature, uses carbon dioxide and can reduce emulsion viscosity.Other gas (for example, ethane and propane) also can reduce emulsion viscosity.

Table 9

CO ₂To the pretreated solid-stabilized crude oil bag aqueous emulsion of acid influence emulsion temperature (℃) at 10sec ^-1Viscosity (cP)

Viscosity (cP) is at 10sec ^-1

There is not CO ₂Use 500psi CO ₂Crude oil #2 35 11,213 1671 By sulfonation electroplating effluent recycling and using oil

Another kind of preliminary treatment oil with the method for the ability that improves its preparation solid-stabilized water-in-oil emulsion is, before emulsification with sulfonating agent preliminary treatment oil.This sulfonation method can cause to oil with to the chemical modification on solids surface.For example, (1) sulfonation method described herein produces the sulphur functional ized components of oil, and these components are surface-active, thereby helps the formation of water-in-oil emulsion; (2) if there is aphthenic acids in the oil, sulfonation will connect sulfonic group by chemistry and enlarge markedly their acidity and interfacial activity; (3) sulfonic group of sulfonating agent also will make described solids functionalisation of surfaces, so modify the solids surface to improve it and the interaction of the surface active composition of oil (be pre-existing in the oil or produce from sulfonating reaction); And the alkaline nitrogen component of (4) oil is converted into corresponding sulfonate and/or sulfate.These salt are bigger than the surface-active of described alkaline nitrogen component own, so, can improve the stability of solid-stabilized water-in-oil emulsion. Use the method that the sulfonation chemical method prepares solid-stabilized water-in-oil emulsion

Adding before the solid particle or using sulfonating agent preliminary treatment oil afterwards, then, interpolation water.With little aliquot or add water continuously and mixture shear-mixed (preferably between 1000～12000rpm) reached and be enough to make water to be dispersed in time (generally being 0.5～24 hour) in the oil-continuous phase as droplet.Preferably, the water concentration in the water-in-oil emulsion is 40～80%, more preferably 50～65%, and most preferably 60%.

Preferred sulfonating agent is the concentrated sulfuric acid.Sulfuric acid is 0.5～5wt% to the preferred processing ratio of oil based on the weight of oil, more preferably 1～3wt%.Other sulfonating agent can be used separately or use with other agent combination.Such sulfonating agent is described in E.E.Gilbert usually, sulfonation and relevant reaction (Sulfonation and Related Reactions), Interscience, New York, (1965).May be applicable to that other sulfonating agent commonly used of the present invention comprises: the mixture of oleum, sulfur trioxide, alkaline disulfate, pyrosulfate, chlorosulfonic acid and manganese dioxide and sulfurous acid.Treatment temperature in the sulfonation process is-20 ℃～300 ℃, preferably 10 ℃～100 ℃, and be more preferably 20 ℃～60 ℃.Can pass through the whole bag of tricks accelerated reaction, described method comprises, the heat that does not limit, machinery, ultrasonic wave, electromagnetism, vibration, mixing and spraying.

Those of ordinary skills can understand, especially can regulate the amount that is applicable to sulfonating agent of the present invention according to the character of sulfonating agent, asphalitine and resin content in the oil.Containing a large amount of bitum oil may be than the sulfonation that contains the littler degree of a small amount of bitum oil require.Can use the amount that oily medium pitch matter is measured in standard method known in the art.The sulfonation scope can be 0.01～40% of a mass of solid particles, preferably 0.1～10%, and be more preferably 0.1～2%.

A kind of method of implementing embodiment of the present invention is at first with oily sulfonation, to add solid particle then.Yet earlier the interpolation solid particle is preferred with the mixture sulfonation again in the oil.Described solids can be silica, clay, hydrophobicity granulate and/or not functionalized and functionalized pitch and corresponding mixture thereof.Solids is 0.05～2.0wt% solids to the preferred process ratio of oil based on the weight of oil.

The hydrophobicity granulate of the embodiment of the present invention is so any granulate: wherein, hydrophobicity greater than the granulate quality 50% and less than 99.9%, hydrophilic segment or polarity part less than the granulate quality 40% and greater than 0.1%.Described hydrophilic segment or polarity part can form by the sulfonation of hydrophobicity granulate with the composition of oil.The example that is applicable to hydrophobicity granulate of the present invention includes but not limited to: the phyllosilicate of phyllosilicate (phylosilicates), lignin, brown coal, coal, hard asphalt, silica, dolomite (dolamite), metaloyides, layered oxide and season exchange.

Functionalized and not functionalized pitch also is effective solids of the pretreated solid-stabilized water-in-oil emulsion of preparation sulfonate.Particularly, (preferably flooding 24 hours down at 55 ℃) the phosphorylation pitch that has fully flooded in oil is effective solid.Described pitch can be their native state and use or can functionalised or use afterwards by sulfonating agent of the present invention is functionalized.Functional moiety's limiting examples is sulfonic acid, phosphoric acid, carboxylic acid, nitric acid or its salt, and hydrophilic group.

After emulsion preparation, can regulate the pH of emulsion like that by the aforementioned usefulness dilute acid pretreatment oil that in first embodiment of the present invention, relates to.As previously mentioned, in the weak base adding emulsion with amount of calculation, emulsion experience shear-mixed is reached is enough to raise the time of pH to desired level (preferably in 5～7 scopes).Regulate pH and choose wantonly, make the basicity of oil reservoir rock stratum buffering emulsion to oil reservoir because wish in some cases to inject acid emulsion.

The viscosity of emulsion increases along with sulfonation.Yet emulsion viscosity is not the linear function of sulfonating agent addition.The viscosity of emulsion is along with sulfonation increases with the speed that reduces.Therefore, the user can keep the required rheological equationm of state simultaneously by the stable solid-stabilized emulsion that increases progressively of sulfonation preparation.As United States Patent (USP) 5,855, discuss in 243 and 5,910,467 like that, also can reduce the viscosity of emulsion by adding gas.

Though can sulfonation prepare the oil of the required whole amounts of this emulsion, also can add before water and the emulsification, the oil of the slip-stream of sulfonated oil or main batch subsequently, makes described slip-stream mix with oily master stream.The preferably untreated crude oil in this oily master stream, but, it can be any oil also, comprises processed to strengthen ability that its forms stable emulsion or processed and optimize the oil of its rheological characteristic.If adopt this slip-stream method, just regulate slip-stream and handle the required solids and the amount of sulfonating agent according to acquisition required amount in the emulsion that forms.

Embodiment:

Use crude oil #2 and another kind of oil (crude oil #5) has been set forth this embodiment of the present invention, because adopt U.S.5, the method for describing in 927,404,5,855,243 and 5,910,467, these oil do not form stable solid-stabilized emulsion.Yet, as shown in following test, improved the ability of the stable solid-stabilized water-in-oil emulsion of oily formation with sulfonation electroplating effluent recycling and using oil.

In a type testing, solid particle is added in the oil, then sulfonation.Utilize the concentrated sulfuric acid to make sulfonating agent, with the processing ratio interpolation of 3 parts of acid of per 100 parts of oil.On the electric hot plate that is fixed to about 50 ℃ of temperature, use the magnetic stirrer said mixture.Then, add water with little aliquot in oil under mixing, it causes solid-stabilized water-in-oil emulsion.

Make these emulsions experience following test:

1. at 25 ℃ of bin stabilities of assigning 48 hours

2. optical microscopy and NMR measure water droplet size/Size Distribution

3. centrifugal stability (described in appendix-1)

4. stability of emulsion: flow through sandpack column (having provided this ultra micro percolation test method in the appendix-1)

Embodiment 1

By following method with crude oil #2 and the sulfonation together of solid granulate: in glass container 12 gram (g) crude oil #2 and solid particle are mixed, this solid particle comprises montmorillonite (monomorillonite) (the Organotrol  1665 that 0.06g 2-methyl-benzyl butter embed; Product) and the untreated Billings pitch of 0.12g ASP-97-021 (product of Exxon) CimarCorp..Under 50 ℃, mixture was stirred 72 hours.Ratio with 3 parts of acid of per 100 parts of oil adds sulfuric acid, under 50 ℃ mixture is stirred 24 hours.

Then, (every liter of distilled water comprises 9.4g sodium chloride, 3.3g CaCl with the oil of sulfonation and solids and the synthetic saline solution of 18g ₂(calcium chloride) 2H ₂O, 0.48g MgCl ₂(magnesium chloride) 6H ₂O and 0.16g potassium chloride).Under 5000rpm, drip salt solution during 30 minutes.The emulsion that will form like this under 7500rpm was again mixed 15 minutes.

Adopt the stability of the solid-stabilized emulsion of oily foreign minister of as the test of the method for ultra micro percolation test described in the appendix-1, producing.The sand of using in this test is Ottawa sand, and oil and sand were descended centrifugal 1 minute at 50 ℃.The double sample shows have 0% and 3.2% salt solution to ooze out (%bbo) after injection is by sandpack column.Light microscopy shows that drop diameter is less than 20 microns, and most of particle diameter is less than 7 microns.

Embodiment 2

Press preceding method with crude oil #5 and oxidized asphalt (OX-97-29-180; The product of Imperial Oil) sulfonation together.But, in this embodiment, before interpolation sulfonating agent (sulfuric acid is with the ratio interpolation of 3 parts of sulfuric acid of per 100 parts of oil), oil and pitch were stirred 2.5 hours down at 50 ℃ together.

The product of sulfonation is mixed with described synthetic saline solution.The mixture that forms contains 60% water.The outer phase emulsion of this oil has 1.6 pH, adds ammonium hydroxide again with its neutralize pH of 7.3, mixes under 350rpm 15 minutes on Arrow 850 mixers then again.The pH of emulsion is near the pH of crude oil #5.This emulsion shows in the ultra micro percolation test does not have salt solution to ooze out.Liquid-drop diameter is less than 10 microns, and most of water droplet is less than 5 microns.The rheological equationm of state of using cone and plate viscometer mensuration has confirmed high stability of emulsion, that is, viscosity keeps substantially constant with cycle-index.

Embodiment 3

Use crude oil #5 and carried out identical test as the montmorillonite (Organotrol  1665, Cimbar Performance Minerals, the product of CartersvilleGA) that the 2-methyl-benzyl butter of solid granulate embed.Crude oil is mixed with solid particle, before adding sulfuric acid, stirred 4 hours down at 50 ℃.In addition, this mixture of sulfonation as stated above.

Add aforementioned synthetic saline solution in above-mentioned oil and the solids and mix like that as described above.Also add ammonium hydroxide the emulsion pH level that forms is adjusted to 7.5, mixed 15 minutes under 350rpm with Arrow 850  mixers again.The water liquid-drop diameter of the outer phase emulsion performance of this oil is less than 10 microns, and most of salt water droplet diameter is less than 5 microns.Find do not have salt solution to ooze out using the ultra micro percolation test method that Berea sand describes in by appendix-1.

Embodiment 4

With crude oil #2 and untreated pitch (ASP-97-021; Imperial OilCorporation, the product of Canada) sulfonation together.Before interpolation sulfuric acid, oil and pitch were stirred 72 hours down at 50 ℃ together.In addition, carry out sulfonation by abovementioned steps.

Add aforementioned synthetic saline solution and mix as stated above and produced solid-stabilized water-in-oil emulsion.But, in this embodiment, do not regulate emulsion pH but maintenance acidity.Optical microscopy shows that the water liquid-drop diameter is less than 10 microns, and most of liquid-drop diameter is less than 5 microns.Find do not have salt solution to ooze out using the ultra micro percolation test method that Ottawa sand describes in by appendix-1.

Embodiment 5

By aforementioned like that with 12g crude oil #2 and 0.06g hydrophobicity granulate Wolastafil-050-MH-0010  (calcium metasilicate of methyl alkoxy silane coating contains 1% coating--the product of United Mineral Corp. of calcium metasilicate weight) sulfonation together.In this embodiment, before interpolation sulfuric acid, under 50 ℃, oil and granulate were stirred 2.5 hours.

Produced a kind of solid-stabilized water-in-oil emulsion by preceding method, emulsion pH has been adjusted to 6.1 with ammonium hydroxide.Light microscopy has disclosed, and the water liquid-drop diameter is less than 5 microns.The presentation of results of ultra micro percolation test, emulsion does not have salt solution to ooze out after injecting.Rheometer test shows that viscosity does not have marked change with cycle-index, the high shear stability of its indication.

Embodiment 6

Use crude oil #2 and as phosphorylation pitch (the Kew 97-149  of solid particle; Imperial Oil Corporation, the product of Canada) prepared a kind of solid-stabilized water-in-oil emulsion.Described oil and solids are added together, such as described above, before interpolation sulfuric acid, add oil and solid together, mixture was stirred 48 hours down at 50 ℃.

Application Optics microscopy, the water-in-oil emulsion of formation show that the water liquid-drop diameter is less than 5 microns.The ultra micro percolation test has disclosed does not have salt solution to ooze out.Rheometer test has been indicated high stability of emulsion, that is, viscosity keeps substantially constant with cycle-index. With lignosulphonic acid salt additives preliminary treatment oil

Another kind of preliminary treatment oil is to add a kind of lignosulphonic acid salt additives in the preparation emulsion in the oil to go to the method that improves its and form the ability of stable solid-stabilized water-in-oil emulsion.The salt of lignosulphonic acid (for example, salt such as sodium, potassium, ammonium, calcium) is surface-active, be added in oil/aqueous mixtures after, they tend to accumulate in oil/water termination.This effect has increased oily interfacial activity, so improved the stability of emulsion.

The preparation of the solid-stabilized emulsion that lignosulphonates are handled

In order to implement this embodiment of the present invention, adding before the solid particle or (but before emulsification) interpolation lignosulphonic acid salt additives in the oil afterwards.For easy and clear for the purpose of, this manual will be referred to add in the oil a kind of lignosulphonic acid salt additives.Yet, should understand, can use the combination of different lignosulphonic acid salt additives and implement this embodiment of the present invention.Under 25～40 ℃, add the lignosulphonic acid salt additives and reach 5～10 minutes with following processing ratio, that is, based on the weight 200～20 of oil, 000ppm, more preferably 500～5000ppm, and further preferred 500～1000ppm.Adding before the lignosulphonic acid salt additives or adding solid particle afterwards, follow, with little aliquot or add water continuously.Then, the shear-mixed of the speed of mixture experience 1000～12000rpm is reached be enough to and make water be dispersed in time in the oil-continuous phase as droplet.Preferably, the water concentration in the described water-in-oil emulsion is 40～80%, is more preferably 50～65%, and most preferably is 60%.

In mixed process, the temperature of emulsion will be elevated to and be higher than room temperature (25 ℃).The temperature of control emulsion is not crucial in mixed process, and but, the higher temperature between 40～75 ℃ is preferred.

Oil-soluble and hydrotropic lignin sulfonate additive all can be used to strengthen the stability of above-mentioned solid-stabilized water-in-oil emulsion.The limiting examples of hydrotropic lignin sulfonate has, the sulfonate of monovalent cation (for example, sodium, potassium and ammonium).The limiting examples of oil-soluble lignosulphonates has, the sulfonate of bivalent cation (for example, calcium, magnesium and iron).Preferably use water-soluble additives, this is owing to carry and answer the cause of water as delivery solvent easily.Preferred hydrotropic lignin sulfonate additive is an ammonium lignin sulfonate.In addition, also can utilize the mixture of lignosulphonates to produce effect identical or that strengthen.

Found that a kind of hydrophobic silica-Aerosil  R972 is the effective solid of several oil.The present invention has set forth, and uses based on the weight of the oil Aerosil  R-972 as the processing ratio of 0.15wt%.Also can utilize as disperse with glossy wet swell soil, organic soil or carbenes matter solid other hydrophobic solid.Also can use the solid hydrophilic particle.It is 0.05～0.25wt% based on the weight of oil that solids is preferably handled ratio.

We can be earlier with adding described solid granulate behind the lignosulphonic acid salt additives preliminary treatment oil.Yet, preferably, in oil, add described solid granulate earlier, in mixture, add the lignosulphonic acid salt additives then.Randomly, can at first use lignosulphonates additive treating solid granulate, the solid that will handle before adding water and mixing is added in the oil again.As previously mentioned, can use water-soluble or the described solids of oil-soluble lignosulphonic acid salt additives preliminary treatment.Use any lignosulphonic acid salt additives for selecting, depend on the classification of the solids that needs are handled.Usually, with water-soluble lignosulphonates additive treating hydrophobic solid thing, and with oil-soluble lignosulphonates additive treating solid hydrophilic thing.Such selection can suitably be modified the surface of solids and the suitableeest hydrophily and hydrophobicity will be provided.

Though this embodiment of the present invention can make the lignosulphonates preliminary treatment prepare the oil of the required whole amounts of desired emulsion, but also can be before interpolation water and emulsification, the oil of the slip-stream of preliminary treatment oil or main batch subsequently, makes described slip-stream mix with the master stream of oil.The preferably untreated crude oil in this oily master stream, but, it can be any oil, comprises processed to strengthen ability that its forms stable emulsion or processed and optimize the oil of its rheological characteristic.If adopt this slip-stream method, just regulate slip-stream and handle the required solids and the amount of lignosulphonic acid salt additives according to acquisition required amount in the emulsion that forms.

This embodiment of the present invention can be combined the surface-active that further improves oil with method with inorganic acid or organic acid preliminary treatment oil.Diluted acid adds and can or carry out afterwards before lignosulphonates add, because the interpolation order of acid and lignosulphonic acid salt additives is not crucial.But acid is added and lignosulphonates add and should carry out in the past in emulsification.If lignosulphonates are added to add with acid to be combined, just can regulate the pH of emulsion by the weak base of interpolation amount of calculation as described above, thereby rising pH arrives required level (the preferably pH between 5～7).

Embodiment

Crude oil #4 and crude oil #6 have been demonstrated the present invention, because use U.S.5, the method for describing in 927,404,5,855,243 and 5,910,467, these crude oil do not form stable solid-stabilized emulsion.Crude oil #6 is a kind of low viscosity crude oil.In a type testing, be that the processing ratio of 0.05～0.5wt% adds the lignosulphonic acid salt additives with weight in oil, and utilize Silverson  homogenizer that 000rpm mixed 10 minutes down about 1000～12 based on oil.In these embodiments, ammonium lignin sulfonate and Lignosite are used as described lignosulphonic acid salt additives.With the weight based on oil is that 0.15wt% adds solid particle (swell soil of dispersion or hydrophily silica), then, further mixes.Then, in mixture, add water, further mix and solid-stabilized water-in-oil emulsion is provided with little aliquot.

Emulsion by method for preparing experiences following test:

1. at 25 ℃ of bin stabilities of assigning 48 hours

2. optical microscopy and NMR measure water droplet size/Size Distribution

3. centrifugal stability (seeing appendix-1)

4. stability of emulsion: flow through sandpack column (having provided the details of ultra micro percolation test method of operating in the appendix-1)

5. use Brookfield  viscometer (awl (#51) and plated construction) 60 ℃ down 1.92～

384sec ^-1The shearing scope in measure the emulsion flow sex change.

The crude oil #4 of embodiment-1.

Provided result of the test in the table 10 with ammonium lignin sulfonate or Lignosite preliminary treatment crude oil #4.Adopt lignosulphonates (0.5wt%) preliminary treatment and a kind of hydrophobic silica (Aerosil  R972) (0.15wt%) to form a kind of solid-stabilized 60/40 water-in-oil emulsion.

As shown in table 10, this lignosulphonates preliminary treatment has strengthened the stability of emulsion, compares with untreated solid-stabilized water-in-oil emulsion, and the minimizing of being oozed out (%bbo) by salt solution in the ultra micro percolation test has confirmed this point.

Table 10

0.5wt% ammonium lignin sulfonate and Lignosite are for from crude oil #4 preparation

Additive stability (%bbo) emulsion viscosity (cP) that influences under 60 ℃ of the lignosulphonates ultra micro diafiltrations of solid-stabilized water-in-oil emulsion does not have 38 2743 ammonium lignin sulfonates, 4 2620 Lignosites 8 2620

The crude oil #6 of embodiment-2.

Prepared a kind of solid-stabilized 60/40 water-in-oil emulsion with crude oil #6 and 0.15wt% hydrophobic silica-Aerosil  R972.Do not adopt the lignosulphonates preliminary treatment.This emulsion instability has 40% water to ooze out in the ultra micro percolation test.Emulsion is at 60 ℃ and 9.6sec ^-1Under viscosity be 983cP.

Yet when having prepared 60/40 same water-in-oil emulsion with the pretreated crude oil #6 of 0.5wt% ammonium lignin sulfonate, the stability of emulsion has strengthened, and water oozes out and reduces to 17%.Emulsion is at 60 ℃ and 9.6sec ^-1Under viscosity increase to 1064cP a little.

Embodiment-3. uses the 50/50 crude oil admixture of crude oil #4 and crude oil #6

Use 50% crude oil #4 and 50% crude oil #6 admixture has prepared untreated solid-stabilized 60/40 water-in-oil emulsion.Solid particle comprises the hydrophobic silica-Aerosil  R972 based on the 0.15wt% of described oily admixture weight.The water leaching rate of untreated solid-stabilized emulsion is 32%.This emulsion is at 60 ℃ and 9.6sec ^-1Under viscosity be 2129cP.

50/50 the crude oil #4/ crude oil #6 admixture pretreated with the 0.5wt% ammonium lignin sulfonate prepared same emulsion.The enhancing of the solid-stabilized emulsion exhibit stabilization that lignosulphonates were handled reduces to 5% in being oozed out by salt solution and has confirmed this point.This emulsion of handling is at 60 ℃ and 9.6sec ^-1Under viscosity remain on 2129cP.Tables of data understands that above-mentioned processing has strengthened stability of emulsion, but does not change viscosity. The preliminary treatment of the oil by the hot air oxidation

Another preliminary treatment embodiment that can be used to increase the stability of solid-stabilized water-in-oil emulsion is, adding before the solid particle or afterwards, the described oil of heat treatment in the presence of air or oxygen.

The mixture of heat treating oil or oil and solid particle in the presence of air or oxygen causes various reactions takes place on the coil neutralization solid particles surface.What (1) have benzyl carbon is oxidized to corresponding acid, ketone or quinone product with those aromatic component with oil of oxidable fused rings (including but not limited to naphthalene and anthracene).The organic sulfur and the nitrogen compound that exist are oxidized to sulfoxide and nitrogen oxide.The compound of oxidation is bigger than the surface-active of described aromatic component own, so the energy strong adsorption is improved the stability of solid-stabilized water-in-oil emulsion in solid particles surface.(2) if aphthenic acids exists as the salt of bivalent cation (for example, calcium), air oxidation just can be converted into these salt aphthenic acids and corresponding metal oxide (for example, calcium oxide).Free aphthenic acids can be adsorbed on the solids surface, also improves the stability of solid-stabilized water-in-oil emulsion.(3) make solid particle dehydration with air purge heat treatment, improve it and the interaction of the surface active composition of oil (preexist in the oil or produce) so modify the surface of solids from air oxidation. The oil of using the hot air oxidation prepares solid-stabilized emulsion

In order to utilize this method to prepare solid-stabilized water-in-oil emulsion, under the situation that is blown into air or oxygen, make oil and solids particles by physical modification and chemical modification oily heat treatment time enough and temperature.Preferably, with every barrel of 20～100 standard cubic foot per hour the preferred rate of (scf/bbl/hr) be blown in the atmosphere of air or oxygen, with oil be heated to 110～180 ℃ temperature reach 15 minutes～6 hours.

Can before the hot air oxidation step, during or afterwards, but should before emulsification, add solid particle.But, preferred elder generation adds solids again to the oxidation of mixture hot air in oil.Described solid particle can be a hydrophily or hydrophobic.Found that the pyrogenic silica of selling with trade name Aerosil  R972 or Aerosil  130 (product of DeGussa Corp.) is effective solids of some oil.Also can utilize other solid particle, for example, the swell soil of swell soil, dispersion, kaolin, organic soil or carbenes matter solid.

The amount of adding the solid particle in the oil to can be at about 1%～about 90%, preferred 0.01～20wt% based on the weight of oil and is more preferably changed in 0.05～5.0wt% scope.Under higher concentration, solids will be the slurry of high solid thing content with the mixture of oil.

Swell soil (for example, at Wyoming, Ga or those of other a lot of local exploitations in the world) is particularly suitable as the stabilizing agent of water-in-oil emulsion.After the exploitation, these clays nature is made of the agglomeration of particles body, and they can be scattered in the water neutralization and resolve into the unit with 2 microns or littler average grain diameter by shearing force.Yet each of these particles all is the stratiform unit, and it comprises about 100 layers of 1nm basic silicate layer thick, that combine by the atom (for example, calcium) that comprises in the layer.By exchange atoms, for example, calcium is replaced by sodium or lithium (they are bigger atoms, and the hydrone in the fresh water is had strong sucking action), makes swell soil contact fresh water then, and swell soil just resolves into the thick layer of single 1nm (being called basic granules).The chemical action of this leafing process is that the clay chemistry those skilled in the art know.The result of leafing process produces the gel that is made of the swell soil that disperses.

Preferred solids is swell soil dispersion or leafing that obtains from above-mentioned leafing process as gel.Change in the amount that the hot air oxidation step added the gel in the oil in the past to can be 5～95% gel (preferred 40～60%) scope in the weight based on oil.The amount of the swell soil solid in the gel can change in 1～30% scope based on the weight of water.If bentonite gel is used as described solid particle, and be added to coil neutralization experience hot air oxidation step, just from reactor, drive away the water that is steam.The water that should react up at least 80% is purged, and preferred at least 95% water is purged, and further preferred water up to 100% is purged.

Preferably, oxidation slip-stream or the oil and the mixture of solids main batch, subsequently, add water and mix before (that is, before emulsification), described slip-stream is mixed with oily master stream.The preferably untreated crude oil in this oily master stream, but, it can be any oil also, comprises processed to strengthen ability that its forms stable emulsion or processed and optimize the oil of its rheological characteristic.If untreated crude oil is described master stream, preferred fusion ratio is the oil of oxidation in 0.5～5% untreated oil master stream, more preferably 0.1～2.5%.

After air oxidation step and solid particle add, with little aliquot or add water continuously, the shear-mixed of mixture experience 1000～12000rpm is reached be enough to make water be dispersed in time in the oil-continuous phase as droplet.In mixed process, the temperature of emulsion will be elevated to more than 25 ℃ the room temperature.The temperature of control emulsion is not critical in mixed process.But, 40～70 ℃ higher temperature is preferred.

Can utilize catalyzer to come the accelerating oxidation reaction.The catalyzer (for example, iron, manganese or nickel, perhaps their oil soluble metal salt) that can use pulverizing comes catalytic oxidation speed and the selectivity that influences oxygenated products.The technology of the catalyzer of this class accelerating oxidation and this class catalyzer of application is well known in the art, so this paper does not discuss them.Can under high pressure carry out oxidation with further rate of catalysis reaction and realization product selectivity, but, the oxidation under normal pressure is preferred.

Available diluted mineral acid or organic acid are further handled the oil of oxidation and are provided other stability to solid-stabilized water-in-oil emulsion.Preferred acid treatment ratio is 8～30,000ppm.If adopt this acid pre-treatment step, the preferable range that can regulate pH to 5～7 of the emulsion of formation by the weak base that in emulsion, adds amount of calculation.Yet, regulate pH and choose wantonly, make the basicity of oil reservoir rock stratum buffering emulsion because wish in some cases to inject acid emulsion to oil reservoir.Ammonium hydroxide is the preferred alkali that pH regulates.Stronger alkali (for example, NaOH, potassium hydroxide and calcium oxide) has side effect to stability of emulsion.Possible explanation about this effect is that highly basic tends to transform emulsion (that is, transform water-in-oil emulsion and become O/w emulsion).The present invention does not wish such conversion.

Except the stability that increases solid-stabilized water-in-oil emulsion, diluted acid is handled the viscosity that has also reduced emulsion.The syringeability that reduces to help to strengthen emulsion of this viscosity.Also may be favourable in the others of EOR method, for example, when utilizing emulsion, with the rheological characteristic of emulsion rheological characteristic coupling with subterranean oil to be exploited as displacing fluid.Also can add the viscosity of gas with further reduction emulsion.

Embodiment

In a type testing, 200g oil is placed Parr  autoclave or three neck glass flask, be blown into 80～100scf/bbl/ hour air continuously, oxidation is 2～6 hours under 150～160 ℃ temperature.Then, with different ratios with the oil of this oxidation and the oily fusion of untreated oil or other hot air oxidation, the specific embodiment that correlative detail sees below.Add a kind of hydrophobic silica-Aerosil  R972 with 0.05wt%～0.15wt% in the oily admixture of oxidation based on the weight of oil.After adding solids, utilize Silverson  homogenizer product mix.Then, under mixing, add water and produce solid-stabilized water-in-oil emulsion with little aliquot.

As for the preferable case of the mixture of the bentonite gel of hot air oxygenated oil and dispersion, at first oil is mixed with gel and form slurry.In reactor, be blown into air or oxygen, temperature is elevated to 150～170 ℃.Drive away the water that is vapor form, condensation is for recovery and reuse outside.

As for the optional case in the oil that acid is added to oxidation, the sulfuric acid of 10ppm is added in the sample of oxidation, mixed 10 minutes down at 40 ℃.By above-mentioned solids and the water of under mixing, adding like that.

Emulsion by method for preparing experiences following test:

1. at 25 ℃ of bin stabilities of assigning 48 hours

2. optical microscopy and NMR measure water droplet size/Size Distribution

3. centrifugal stability (having described) at appendix-1

4. stability of emulsion: flow through sandpack column (having provided the details of ultra micro percolation test method of operating in the appendix-1)

5. use Brookfield  viscometer (awl (#51) and plated construction) 1.92～384sec under 60 ℃ ^-1The shearing scope in the emulsion flow sex change measured. The crude oil #4 fusion of embodiment-1. untreated crude oil #4 and air oxidation

In untreated crude oil #4, add Aerosil  R972 with the processing ratio of 0.15wt%, then, add water and mix and form 60/40 solid-stabilized crude oil bag aqueous emulsion.Though it is this emulsion is a stable storage, unstable in centrifugal test and ultra micro percolation test.The drop diameter that disperses is used Berea sand and is observed 54% water by the ultra micro percolation test method of describing in the appendix-1 and ooze out in 2～40 micrometer ranges.Emulsion is at 60 ℃ and 9.6sec ^-1Under viscosity be 3644cP.

By preceding method another batch crude oil #4 has been carried out the hot air oxidation.With the crude oil #4 of this hot air oxidation and untreated crude oil #4 ratio fusion with the oil/untreated oil of the processing of 2.5wt%.Carry the crude oil #4 of hot air oxidation with 1: 2 ratio in toluene.Add hydrophobic silica-Aerosil  R972 with processing ratio based on the weight 0.15wt% of the oil of fusion.Add water and mixing and prepare 60/40 solid-stabilized crude oil bag aqueous emulsion.The droplets size distribution indication that NMR measures, 90% drop diameter is less than 2 microns.Compare with the solid-stabilized emulsion of untreated crude oil #4, the improved stability of emulsion, reduce to 10% by water seepage discharge in the percolation test of Berea ultra micro and confirmed this point.Emulsion is at 60 ℃ and 10sec ^-1Under viscosity be 2452cP.In addition, viscosity profile was sheared in the circulation at 1 hour and has been repeated.

Added the viscosity of ethane gas with the solid-stabilized water-in-oil emulsion that reduces the hot air oxidation.The saturated viscosity of emulsion under 60 ℃ of formation that makes of ethane with 400psi has dropped to 390cP from 2452.Duration of test at 5 days, emulsion is for the ethane interpolation with at 10sec ^-1Under shearing be stable. The crude oil #4 of embodiment-2. oxidation and the admixture of low viscosity crude oil #6

This test in, with different ratios with crude oil #4 and a kind of low viscosity crude oil (crude oil #6) fusion.Add a kind of hydrophobic solid-Aerosil  R972 with the 0.15wt% solids than the ratio of the oil of fusion, add 10ppm sulfuric acid simultaneously and mixed 30 minutes.Then, add water with little aliquot and mix and the water in oil emulsion of 60/40 fusion is provided.The result is as shown in table 11.From these data as seen, the ratio that increases low viscosity crude oil #6 make 60/40 fusion the viscosity of water-in-oil emulsion from 3644cP (at 60 ℃ and 9.6sec ^-1Following measure) be reduced to 983cP.Yet, the poor stability of emulsion, this oozes out 30～40% by water in the ultra micro percolation test of using Berea sand and has confirmed.

Table 11 Crude oil #4/ crude oil #6 %bbo Viscosity, cP Mix proportions60 ℃, 96s ^-110,0/0 38 364,475,/25 34 262,150,/50 32 212,925,/75 41 163,80/,100 40 983

The hot air oxidation was to strengthening the impact effect of the stability of emulsion that forms before table 12 showed emulsification.To the oxidation of crude oil #6 hot air, cause the crude oil #6 admixture of 75% untreated crude oil #4 with untreated crude oil #4 fusion by preceding method then than 25% hot air oxidation.Add a kind of hydrophobic solid-Aerosil  R972 in this admixture, add 10ppm sulfuric acid simultaneously and mixed 30 minutes.Then, add water with little aliquot and mix and provide 60/40 fusion water in oil emulsion.Result shown in the table 12 has illustrated the effect of this method of the ultra micro percolation test indication of using Berea sand.

Table 12 Oil Salt solution oozes out (%bbo) Viscosity, cP

60 ℃, 96s ^-116 2620 crude oil #6 of 75% crude oil #4,34 262125% crude oil #675% crude oil #425% hot air oxidations

When adding the crude oil #6 of 25% hot air oxidation in untreated crude oil #4, the stability of emulsion has strengthened one times, oozes out percentage by salt solution and is reduced to 16% from 34% and has confirmed this point. Embodiment-3: the solid-stabilized breast of using the bentonite gel preparation of crude oil #4 and dispersion Liquid

The mixtures (oil that provides 70: 30 is to the gel ratio, and the swell soil solid concentration is the 3.5wt% of gel) that are blown into the bentonite gel that 80scf/bbl/ hour air disperses 70 gram (g) crude oil #4 and 30g under 160 ℃ temperature carry out air oxidation and reach 4 hours.Drive away about 25g water from reactor.Product in the reactor is used for preparing solid-stabilized 60/40 water-in-oil emulsion.With the product and the untreated crude oil fusion of air oxidation, the admixture of formation contains the product of 2.4wt% air oxidation, than 98.6% untreated crude oil.

60/40 water-in-oil emulsion that forms shows that in ultra micro diafiltration stability test 12% salt solution oozes out.When adding ethane gas with 400psi, emulsion is stable.

Using said method makes the mixture (oil is 30: 70 to the gel ratio) of the bentonite gel of 30g crude oil #4 and 70g dispersion experience the hot air oxidation.Drive away water from reactor, the product of formation is an oily solid.

Solid-stabilized 60/40 water-in-oil emulsion of having used above-mentioned oily solid preparation of product.The amount of the oily solid of using is 0.1% based on the weight of untreated crude oil.

The emulsion that forms shows that in ultra micro diafiltration stability test 20% salt solution oozes out.The drop diameter that disperses is less than 4 microns. The preliminary treatment oil by heat treatment in inert environments

Another kind of preliminary treatment oil and strengthen the method that its forms the ability of stable solid-stabilized water-in-oil emulsion and be, before emulsification, heat treating oil in inert environments.This embodiment has the additional benefit of the viscosity that reduces solid-stabilized water-in-oil emulsion.

Described heat treatment can:

A) produce the asphalitine solid, this solid itself and/or combine the stability that solid-stabilized water-in-oil emulsion is provided improvement with the solids of outside interpolation,

B) reduce the viscosity of crude oil, it changes the lower emulsion viscosity of solid-stabilized water-in-oil emulsion into, and

C) reservation or degraded aphthenic acids. Prepare solid-stabilized water-in-oil emulsion with heat treating oil

The stable solid-stabilized emulsion that forms in order to strengthen oily physical property and chemical property can be before emulsification, and heat treating oil reaches time enough in the inert environments of enough temperature and pressures.Preferably, heat treating oil reaches 0.5～6 hour by be heated to 250 ℃～450 ℃ temperature under 30～300 pounds/square inch (psi).Do not carry out when this heat treatment can not be blown into air in inert atmosphere, perhaps when being blown into inert gas continuously, carry out.For the heat treated method for optimizing that is not blown into gas, reach 30 minutes with inert gas (for example, nitrogen) flushing oil during beginning, seal autoclave again, be heated to required temperature.Carry out hot pretreated alternative embodiment for being blown into inert gas continuously, in whole heat treatment process, inert gas (for example, argon) bubbling is fed reactor with the flow of 200～450 standard cubic feet per barrels/hour (scf/bbl/ hour).Reduce viscosity if desired to a greater degree, this method is exactly preferred.A kind of method in back will cause the more most destruction of surface-active aphthenic acids, so be that the stable emulsion institute of preparation is more not preferred.Suitably selecting to handle severity reduces to keep with aphthenic acids to cause the suitableeest viscosity.This processing severity can become according to different oil, but in the scope of disclosure.

After the heat treatment, add solids, then add water, mix and the formation solid-stabilized water-in-oil emulsion.The interpolation solids also belongs to scope of the present invention in the oil to go in heat treatment.But, under latter event, need to prove, might make the operating equipment fouling, so optimize heat-treat condition equipment scaling is minimized.

With little aliquot or add water continuously, (preferably reaching with 1000～12000rpm) is enough to make water to be dispersed in time in the oil-continuous phase as droplet with the mixture shear-mixed.Preferably, the water concentration in the water-in-oil emulsion is 40～80%, more preferably 50～65%, and most preferably 60%.In mixed process, the temperature of emulsion will be elevated to and be higher than room temperature (25 ℃).The temperature of control emulsion is not crucial in mixed process, and but, the higher temperature between 40～75 ℃ is preferred.

As for solids, solid particle is preferably hydrophobic.Find that a kind of pyrogenic silica of selling with trade name Aerosil  R972 (product of DeGussa Corp.) is effective to some different oil.Also can use other solid, for example, dispersion with glossy wet swell soil, kaolin, organic soil or carbenes matter solid.Solids to the preferred concentration of oil in the scope of 0.05～0.25wt%.

Preferably, the slip-stream of heat treating oil then, mixed described slip-stream before the interpolation solids to high severity level with the master stream of oil, add water and also mix and the formation emulsion.The preferably untreated crude oil in the master stream of described oil, but, it can be any oil, comprises processed to strengthen ability that its forms stable emulsion or processed and optimize the oil of its rheological characteristic.

For further stable with the heat treated oily solid-stabilized emulsion for preparing, what estimate particularly suitable is to go in emulsification and add 0.1～1.0wt% lignosulphonic acid salt additives in the oil.Preamble has been described the method (that is, adding the lignosulphonic acid salt additives) of the stability of the solid-stabilized emulsion of this enhancing.

Can go in emulsification and add diluted acid in the oil, it will further strengthen the stability of emulsion and reduce the viscosity of emulsion.This paper has also described this diluted acid and has added.

Compare with the solid-stabilized emulsion for preparing with untreated oil, the method for heat treating oil has the additional benefit of the viscosity that reduces solid-stabilized emulsion before emulsification.The ability of this control emulsion viscosity can make the user rheological characteristic of emulsion and the rheological characteristic of oil to be exploited mates the most rightly (particularly when the EOR method of application particular type).Also can add the viscosity of gas with further reduction emulsion.

The method that another kind reduces heat treated solid-stabilized emulsion viscosity is with the emulsion ageing.Heat treated solid-stabilized emulsion can be by making emulsion at room temperature or leave standstill time enough come ageing under higher temperature simply.Can use this method and reduce the viscosity of emulsion more than 50%.Can promote ageing process by centrifugal (preferred repeated centrifugation), it will cause heat treated solid-stabilized emulsion viscosity similarly to reduce.Preferably under 35 ℃～80 ℃ temperature,, carry out under the 000rpm centrifugally reaching 15 minutes～2 hours 500～10.

Embodiment

In a type testing, 200g oil is placed the PARR autoclave, in the pressure limit of 30～280psi, the temperature that is heated to 150～450 ℃ reaches 0.5～6 hour.Do not carry out when this hot preliminary treatment can not be blown into gas in inert atmosphere, perhaps when being blown into gas continuously, carry out.For the hot preliminary treatment that is not blown into gas, reach 30 minutes with inert gas (for example, nitrogen) flushing oil during beginning, seal autoclave again, be heated to required temperature.Carry out hot preliminary treatment for being blown into inert gas continuously, in whole heat treatment process, inert gas (for example, argon) bubbling is fed reactor with 200～450scf/bbl/ hour flow.Then, in heat treated oil, add a kind of hydrophobic solid-Aerosil  R972.Utilize Silverson  homogenizer to mix, then add solids.At last, add water and mixing in oil and the solid particle and solid-stabilized water-in-oil emulsion is provided with little aliquot.

Set forth above-mentioned hot method for pretreating three severity levels, the following character of its influence oil: the acid number (TAN) that (1) is total, the amount of (2) N.heptane insolubles, (3) toluene equivalent (measuring thermogenetic bitum solubility), and (4) viscosity.

Emulsion by heat treated oil preparation has experienced following test:

1. at 25 ℃ of bin stabilities of assigning 48 hours

2. optical microscopy and NMR measure water droplet size/Size Distribution

3. centrifugal stability (described in appendix-1)

4. stability of emulsion: flow through sandpack column (having provided the details of ultra micro percolation test method of operating in the appendix-1)

5. use Brookfield  viscometer (awl (#51) and plated construction) 1.92～384sec under 35 or 60 ℃ ^-1The shearing scope in measure the emulsion flow sex change. Embodiment-1

Prepare 60/40 water-in-oil emulsion with crude oil #2 without any heat treatment, but added 0.15wt% hydrophobic silica (Aerosil  R972).Though it is this emulsion is a stable storage, unstable in centrifugal test and ultra micro percolation test.The drop diameter that disperses is in 0.4～80 micrometer range. Embodiment-2

Wash in advance with nitrogen, in the inert environments of 280psi, reach 6 hours at 360 ℃ of following heat treatment crude oil #2.The oil that produces is at 35 ℃ and 9.6sec ^-1Under viscosity drop to 328cP from 643 centipoises (cP).TAN is reduced to 3.9 from 6.6.Toluene equivalent is raised to 31 from 14, and N.heptane insolubles remains on 2.7% and do not become.

In heat treated crude oil #2, add solid particle-0.15wt%Aerosil  R972, then, add water as described above like that and mix and form the solid-stabilized emulsion of 60/40 Water-In-Oil.The solid-stabilized emulsion that forms is at 35 ℃ and 9.6sec ^-1Under viscosity be 5734cP, its expression is compared with the untreated solid-stabilized emulsion for preparing with untreated crude oil #2 and 0.15wt%Aerosil  R972, emulsion viscosity reduces 63%.The water droplet size of the heat treated solid-stabilized emulsion that NMR measures distributes and has indicated the narrow distribution of drop diameter in 2～10 micrometer ranges.Emulsion-stabilizing ground flows, because do not ooze out by observing water in the ultra micro percolation test of describing in the appendix-1.The pH of emulsion is about 6.2. Embodiment-3

In the inert environments of 90psi, reach 2 hours at 350 ℃ of following heat treatment crude oil #2, the oil that causes handling is at 35 ℃ and 9.6sec ^-1Under viscosity drop to 328cP from 643cP.TAN is reduced to 5.1 from 6.6.Toluene equivalent is raised to 25 from 14, and N.heptane insolubles remains on 2.7% and do not become.

In heat treated oil, add 0.15wt%Aerosil  R972 like that as described above, then, add water and also mix, stable solid-stabilized 60/40 water-in-oil emulsion is provided.NMR has disclosed drop diameter and has been distributed in 2～14 micrometer ranges.In ultra micro diafiltration sandpack column test, there is 14% water to ooze out, do not ooze out and in the microcentrifugation test, observe water.The pH of emulsion is 6.2.Emulsion is at 35 ℃ and 9.6sec ^-1Under viscosity be 7373cP, its expression is compared with the similar solid-stabilized emulsion that the crude oil #2 of dilute acid pretreatment prepares with utilizing preceding method, viscosity reduces over half. Embodiment-4

Prepare 60/40 water-in-oil emulsion with another kind of crude oil (crude oil #4) without any hot preliminary treatment, but added 0.15wt%Aerosil  R972.Press United States Patent (USP) 5,927, the method for describing in 404,5,855,243 and 5,910,467, crude oil #4 does not form stable solid-stabilized emulsion.The physical property of crude oil #4 is contained in the table 2.Though it is this emulsion is a stable storage, unstable in centrifugal test and ultra micro percolation test.The drop diameter that disperses is in 2～40 micrometer ranges.Use Berea sand, observe 54% water in the ultra micro percolation test of in by appendix-1, describing and ooze out.Emulsion is at 60 ℃ and 9.6sec ^-1Under viscosity be 3644cP. The ordinary test that increases about the surface-active of oil

Can reduce to measure because the surface-active of the oil that preliminary treatment causes increases by the interfacial tension of measuring between oil and the water.Interfacial tension is to measure down at 25 ℃ by the sessile drop method of standard.Hereinafter provided the result of untreated crude oil #4 and pretreated crude oil #4.Note, can not utilize the sessile drop method of standard to measure with the interfacial tension result of the crude oil #4 of solid particle and sulfonation processing.

Table 13

The mensuration of interfacial tension

The untreated crude oil #4 32.3 crude oil #4+ solid particles (solids) of oil interfacial tension (dynes per centimeter) 32.6 crude oil #4+ acid preliminary treatment+solids 15.8 crude oil #4+ lignosulphonates+solids 12.5

Solids=0.15wt%Aerosil  R972 lignosulphonates=0.1wt% ammonium lignin sulfonate acid preliminary treatment=8000ppm sulfuric acid

Combine its embodiment preferred and described the present invention.Yet, those skilled in the art will recognize that, can much modify the present invention, conversion and change and do not depart from true scope of the present invention.Therefore, such modification, conversion and change will be understood that among the present invention who is included in the appended claims regulation.

Appendix-1: about the ultra micro percolation test of the stability of emulsion that flows through porous medium

About will form two independently the observed result of the unstable emulsion of macroface (oil/emulsion mutually and a water) depend in order to understand that emulsion flows through the stability of porous medium in rapid, easy test.So, can a certain amount of emulsion that flow through porous medium fully is centrifugal and form two distinct phases, their volume can be used as the measuring of stability of emulsion-flow through with centrifugal after, it is bigger to form water ratio original in water limpid, tangible phase or the emulsion, and emulsion is with regard to the instability that heals.Therefore, a suitable parameters of measuring stability is " salt solution oozes out " or " bbo ", is defined as the water or the salt water section that form tangible independent water in the emulsion.Because it is a ratio, so bbo does not have unit, is in 1 (least stable)～0 (the most stable) scope.The salt solution seepage discharge is to measure under the condition of one group of strict regulations.

A kind of microcentrifugal tube commercially available, bipartite special sintering is used as the container of this test.The bottom is one section pipe of accepting any fluid that flows down from upper tube.Described top is similar to conventional polypropylene microcentrifugal tube, and different is, the bottom is a sinter, and it is small enough to hold sand grains, but fluid is flow through easily.In addition, the two-section pipe has a lid separately, and one of them play supporting role, it make top when upright easily by weighing and operation.They can derive from Princeton Separations, Inc., and Adelphia NJ sells with trade name " CENTRI-SEP COLUMNS ".

The centrifuge of application of heat provides pressure that the emulsion fluid is flow through and places the interior a small amount of sand of upper tube.It is by Robinson, Inc. (Tulsa, 620 types that OK) provide.Temperature is nonadjustable, but is stabilized in 72 ℃ under our condition.Top speed is about per minute 2400 changes (RPM), and the radius of sand post is 8 centimetres (cm), and it provides the centrifugal force of 520g.Milligram like all weight all is measured to recently.

The pillar that provides has a small amount of silica gel that is weighed in the pipe.Discard it, the weight of record two-section pipe.About 0.2 gram (g) sand is weighed into top, adds 0.2 ± 0.01g oil toward top.The typical sand that is used for this test is Berea sand or Ottowa sand.The sand of using in this test becomes with different purposes.For for simplicity, can use not sieved, untreated Ottawa sand that VWR Scientific Products provides.This just provides easy, " tolerant " system, because sand particle argillaceous quite greatly and not.Alternatively, also can use respectively two granularities with 10～1 ratio fusion: a granularity is by the 100Tyler order, but can not pass through 150 orders; And another granularity is by the 150Tyler order.Weighing pipe once more, on the centrifuge of heating centrifugal one minute at full speed then.Shed lower tube, weighing top once more, it is given and shakes out and the weight of top residual oil.Now, sand is glossy wet state, has air and oil in the hole.

Now, 0.18 ± 0.02g emulsion is placed the top of wetting sand, weighing top once more.The weighing lower tube is placed on the below of this pipe and accepts effluent in the centrifugal process.

Only inject independent lower tube with 0.2～0.5g emulsion.This comes as a comparison to determine whether centrifugal (it does not flow through glossy wet sand) of emulsion causes that salt solution separates out from emulsion.This step is called as the microcentrifugation test, and it also is a sign of stability of emulsion.

Then, with time (15～45 minutes) of the centrifugal indication of two-section pipe-depend on oil viscosity and centrifugation rate.The purpose of regulating time span is to arrive a bit, and at this moment, at least 75% emulsion arrives in the lower tube after flowing through layer of sand.If less than show value, just with centrifugal again a period of time of assembly.

After the rotation, write down the weight of two-section pipe up and down once more.If the emulsion instability will be seen limpid water below the bottom of pipe, opaque black emulsion/oil phase.Then, measure the volume of water in the recipient of bottom by the disposable pipette of accurate capillary (100～200 microlitre) that the water suction is equipped with a plunger.These provide (trade name is " Wiretroll II ") by Drummond Scientific Co..Measure the length of water column and be converted into the quality of water by suitable calibration curve capillaceous.So, just can from these measurement results and known emulsion, calculate the water yield of oozing out by the weight rate of original water.

Claims (40)

1. method that improves the stability of solid-stabilized water-in-oil emulsion, described method is included in this step of at least a portion of the preceding described oil of preliminary treatment of emulsification, at least one step that described pre-treatment step comprises the following steps: in described oil, add diluted acid, in described oil, add lignosulphonates, the described oil of sulfonation, the described oil of heat treatment in inert environments, and the described oil of thermal oxide.

2. the method for a recovery of hydrocarbons from subterranean strata, described method comprises the following steps:

(a) prepare a kind of solid-stabilized water-in-oil emulsion as follows

(1) at least a portion of the described oil of preliminary treatment before emulsification, at least one step that described pre-treatment step comprises the following steps: in described oil, add diluted acid, in described oil, add lignosulphonates, the described oil of sulfonation, the described oil of heat treatment in inert environments, and the described oil of thermal oxide

(2) go in the described oil in emulsification and add solid particle, and

(3) add water and mixing until forming described solid-stabilized water-in-oil emulsion;

(b) described solid-stabilized water-in-oil emulsion is injected described subterranean strata; And

(c) from described subterranean strata recovery of hydrocarbons.

3. the method for claim 2, wherein, described solid-stabilized water-in-oil emulsion is used as displacing fluid and comes hydrocarbon in the described subterranean strata of displacement.

4. the method for claim 2, wherein, described solid-stabilized water-in-oil emulsion is used as the flow divert that stops liquid and make the hydrocarbon in the described subterranean strata.

5. claim 1 or 2 method, wherein, described pre-treatment step comprises, in going at least a portion of described oil, emulsification adds diluted acid, described diluted acid is selected from down the group material: the mixture of at least a inorganic acid, at least a organic acid, at least two kinds of inorganic acids, at least two kinds of organic acid mixtures, and at least a inorganic acid and at least a organic acid mixture.

6. the method for claim 5 wherein, is added to described acid in the described oil with per 1,000,000 parts about 8 parts～per 1,000,000 parts of about ratios of 30,000 parts.

7. the method for claim 5, wherein, described method further comprises the following steps: to measure the pH of described water-in-oil emulsion after emulsification, if necessary, regulates described pH so that it is in about scope of 5.0～about 7.0.

8. the method for claim 7 wherein, is regulated the described pH of described water-in-oil emulsion by interpolation ammonium hydroxide in described emulsion.

9. the method for claim 1 or claim 2, wherein, described pre-treatment step comprises, at least a portion of the described oil of sulfonation before emulsification.

10. the method for claim 9, wherein, the step of at least a portion of the described oil of described sulfonation comprises, adds at least a sulfonating agent.

11. the method for claim 10, wherein, described sulfonating agent is a sulfuric acid.

12. the method for claim 10 wherein, is added to described sulfonating agent in the described oil with the processing ratio of about 0.5wt%～about 5wt%.

13. the method for claim 1 or claim 2, wherein, described pre-treatment step comprises, before emulsification a kind of lignosulphonic acid salt additives is added at least a portion of described oil.

14. the method for claim 13 wherein, is added to described lignosulphonic acid salt additives in the described oil with per 1,000,000 parts about 500 parts～per 1,000,000 parts of about ratios of 5000 parts.

15. the method for claim 13, wherein, described lignosulphonic acid salt additives is oil-soluble.

16. the method for claim 13, wherein, described lignosulphonic acid salt additives is water miscible.

17. the method for claim 1 or claim 2, wherein, described pre-treatment step comprises, at least a portion of the described oil of thermal oxide before emulsification.

18. the method for claim 17, wherein, described step of thermal oxidation is to carry out under the temperature between about 110 ℃～about 180 ℃.

19. the method for claim 17 wherein, promotes described step of thermal oxidation by adding catalyzer.

20. the method for claim 1 or claim 2, wherein, described pre-treatment step comprises, before emulsification, and at least a portion of the described oil of heat treatment in inert environments.

21. the method for claim 20, wherein, described heat treatment step is to carry out under the temperature in about 250 ℃～about 450 ℃ of scopes.

22. the method for claim 20, wherein, described heat treatment step is to carry out under the pressure in about 30psi～about 300psi scope.

23. the method for claim 20, wherein, described method further is included in emulsification and goes to this step of interpolation diluted acid in the described oil, described diluted acid is selected from down the group material: at least a inorganic acid, at least a organic acid, the mixture of at least two kinds of inorganic acids, at least two kinds of organic acid mixtures, and at least a inorganic acid and at least a organic acid mixture.

24. the method for claim 20, described method further are included in emulsification and go to a kind of this step of lignosulphonic acid salt additives of interpolation in the described oil.

25. the method for claim 20, wherein, described in inert environments the step of the described oil of heat treatment reduced the viscosity of described solid-stabilized water-in-oil emulsion.

26. the method for claim 20, described method further are included in this step of the described solid-stabilized water-in-oil emulsion of ageing after the emulsification, so the viscosity of described emulsion has reduced.

27. the method for claim 26, wherein, the step of the described emulsion of described ageing comprises, at about 500rpm～about 10, under the 000rpm centrifugal described emulsion reach about 15 minutes～about 2 hours.

28. the method for claim 27, wherein, the described step of the described emulsion of repeated centrifugation.

29. the method for claim 2, wherein, described solid particle is the hydrophobic solid particle.

30. the method for claim 2 wherein, is added the described step of solid particle in the described oil and is carried out after described pre-treatment step.

31. the method for claim 2 wherein, is added the described step of solid particle in the described oil and was carried out in the past in described pre-treatment step.

32. the method for claim 2, wherein, described solid particle comprises at least a of following material: the phyllosilicate of functionalized pitch, not functionalized pitch, swell soil, bentonite gel, kaolin, organic soil, carbenes matter solid, phyllosilicate, lignin, brown coal, coal, hard asphalt, silica, dolomite, metaloyides, layered oxide and season exchange.

33. the method for claim 2, wherein, with described lignosulphonic acid salt additives and the combination of solid hydrophilic particle.

34. the method for claim 2, wherein, with the oil and the combination of solid hydrophilic particle of described thermal oxide.

35. the method for claim 2 wherein, with described solid particle and lignosulphonates additive combination, then, is added to described composition in the described oil before emulsification.

36. the method for claim 2 wherein, is added described solid particle as the gel that is made of solid particle and water.

37. the method for claim 36, wherein, based on the weight of described water, described solid particle accounts for about 1wt%～about 30wt% of described gel.

38. the method for claim 36 wherein, is added to described gel in the described oil in than the process range of described oil at the described gel of about 5wt%～about 95wt%.

39. the method for claim 2 wherein, is added described solid particle with the processing ratio of about .05wt%～about 5wt%.

40. one kind is applicable to that from the solid-stabilized water-in-oil emulsion of subterranean strata recovery of hydrocarbons, described emulsion comprises

(a) oil, wherein, at least a portion of described oil at least one step through the following steps is pretreated: add diluted acid in described oil, add the lignosulphonic acid salt additives in described oil, the described oil of sulfonation, described oil of heat treatment and the described oil of thermal oxide in inert environments;

(b) be suspended in water droplet in the described oil; And

(c) under the condition of described subterranean strata, be insoluble to the solid particle of described oil and described water.