DE2736277C2 - A method of treating clays containing formations against swelling and dispersion of the clays by the action of water and treating composition for carrying out the method - Google Patents

Description

R ₁ -Z ⁺ -R ₃
R ₄

where mean:

Ri = an organic, aliphatic, cycloaliphatic or an aromatic radical having 2 to 40 carbon atoms or a hydrogen radical;

R2, R3 and R4 = organic radicals accordingly the definition of R ,, which has up to 6 carbon atoms and 0 to 2 oxygen or Contain nitrogen atoms, where, when Z = sulfur, R4 is absent is;

Z = a cation derived from nitrogen, phosphorus or sulfur;

X = an anion,

η = an integer equal to the number of monomer units in the polymer; and

m = an integer equal to the number of anions required to maintain electrical neutrality.

2. The method according to claim 1, characterized in that the compound has a ratio of cationic atom to carbon atoms at about 1: 2 to 1:36.

3. The method according to claims 1 and 2 when using an organic, polycationic Polymer with a cycloaliphatic radical Ri, characterized in that that of nitrogen, Phosphorus or sulfur derived cation (Z) and the organic radical (R2) in the ring system are built in.

4. Process according to claims 1 to 3, characterized in that an aqueous carrier fluid is used, which the organic, polycationic polymer in a concentration of about 0.01 to 25% by volume is added.

5. The method according to claim 1, characterized in that a normally as a carrier fluid liquid, substituted, polar hydrocarbon with a boiling point in the range of about 25 to 200 ° C is used, which the organic, polycationic polymer in a concentration from about 0.01 to 25 wt .-% is added.

6. The method according to claim 1, characterized in that the organic, polycationic Polymer polydimethylethylammonium chloride, the condensation product of Ν, Ν, Ν ', Ν'-tetramethylethylenediamine with 1,4-dichlorobutane, polyvinyltrimethylammonium chloride, Poly-3-methacryioxy- (2-hydroxy-propyltrimethylammonium chloride, polyacrylamide-1-propyl-3-trimethylammonium chloride), Polydiallyldimethylammonium chloride, the condensation product of dimethylamine with Epichlorohydrin, optionally branched with ammonia, or the condensation product of dimethylamine is used with 1,4-dichlorobutane.

7. Application of the method according to claim 1 or 2 in the breaking up of earth formations, wherein in addition, a classified, solid, particulate material is pumped into the borehole.

8. Application of the method according to claim 7, wherein a pressure in the borehole is adjacent to a formation is maintained in the borehole which is greater than the fracture pressure of the neighboring formation is.

9. Treatment composition for performing the method according to any one of the preceding Claims, characterized in that they contain about 0.01 to 25% by volume of at least one of the in Claim 1 contains specified compounds.

The invention relates to a particularly simple method for treating clays containing clays Formations against swelling and dispersion of clays by the action of water.

The production of petroleum hydrocarbons is often caused by the presence of clays and others fine particles capable of migration in the formation are disturbed. Usually located These fine particles including the clays are at rest and do not cause blocking or Obstruction of flow to the oil well via the capillary system of the formation. When the fine fabrics are disturbed, they begin to migrate in the flow of production, and often they also cause one Narrowing in the capillaries where they bridge and greatly reduce the flow rate.

The means which perturbs the quiescent fine particles is often the introduction of for the formation of alien water. The external water is often fresh water or relatively fresh water, compared to the saline solution present in the formation. A change in the water can cause that the fine particles disperse from their deposits or from adherence to the capillary walls get free.

Sometimes the loss of permeability or permeability is relative to swelling of clay ascribing fresh water with no migration. Often

W), however, is the swelling of clay from a hike accompanied by fine particles. Sometimes non-swelling sounds can respond to extraneous water and to start hiking. It is believed that swelling clays are the main cause of migration

b5 of the fine particles and / or the swelling are, as at the analysis of formation cores, the presence of swelling clays is an excellent indicator for it is that the formation opposite the break-in

is sensitive to extraneous water while the presence of non-swelling clays merely does not allow any conclusions to be drawn

In general, swelling clays belong to the smectic group, which includes clay minerals such as montmorillonite, Beidellite, nontronite, saponite, hectorite and Saukonite Including Of these clay minerals, montmorillonite is most commonly used in the analysis of Formation cores found. Montmorillonite is commonly associated with clay minerals known as Mixed layer clays are known. For more information, see Jackson's monograph, Textbook of Lithology ", pages 95-103.

Migrating fine particles include a multitude of clays and other minerals of small particle sizes, z. E.g .: feldspars, fine quartz particles, allophane, dadinite, talc, mit, chlorite and the swelling clays even for additional information, see Theng's monograph, The Chemistry of Clay-Organic Reactions ”, pages 1 to 16, referenced. 2 «

Clays can also be used in areas other than reducing permeability or permeability Cause trouble. If they are a component in slates, sandstones or others Formations can come into contact with foreign water or sometimes with any water cause the formation to lose its strength or even to disintegrate. This is a problem with building Foundations, road documents, when drilling boreholes and in any situation where the strength ju the formation plays a role.

There have already been numerous attempts to reduce the negative effects of water on clay and / or to control other fine particles. Most of these attempts took place in the oil industry. A suggestion consists of converting the clay from the swelling sodium form (or the rarer, swelling lithium form) into a to convert another cation form that does not swell as much.

Examples of cations which form relatively non-swelling clays are potassium, calcium, ammonium and Hydrogen ions. When a solution of these cations, mixed or individually, flows over a clay mineral, they easily replace the sodium ions and the clay is converted into a relatively non-swelling form, see -r> Theng, Tables 2,3 and 4. The application of an acid, of potassium, calcium or ammonium ions to the Exchange for sodium ions was successful in preventing damage to formations, which are susceptible to clogging or deterioration as a result of clays in their composition are.

In the following, the state of the art and individual measures, insofar as they relate to the invention concern, received. For further details, please refer to each of the literature references cited below Reference is made to this in the present description only to the extent deemed necessary received. These prior art references are: bo

US patents: 27 61 843, 28 01 984, 28 01 985, 29 40 729, 33 34 689, 33 82 924, 34 19 072, 34 22 890, 34 83 923, 35 78 781, 36 03 399, 37 41 307, 38 27 495, 38 27 500.38 33 718;

Barkman, J. H .; Abrams, A .; Darley, H. C. H .; and Hill, n ", H. J .; "An Oil Coating Process to Stabilize Clays in Fresh Water Flooding Operations", SPE-4786, SPE from AIME, Symposium on Formation Damage Control, New Orleans, La, USA, February 77, 1974;

Coppel, Claude E .; Jennings, Harley X .; and Reed, M. G .; "Field Results From Weils Treated., With Hydroxy-Aluminum ", Journal of Petroleum Technology (Sept 1973), pp. 08 - U12;

Graham, John W .; Monoghan, P. H .; and Osoba, J. S .; "Influence of Propping Sand Wettability of Productivity of Hydraulically Fractured Oil Wells," Petroleum Transactions, AIME, Vol. 216 (1959);

Hower, Wayne F .; "Influence of Clays on the Production of Hydrocarbons," SPE-4785, SPE of AIME, Symposium on Formation Damage Control, New Orleans, La, USA, February 77, 1974;

Hower, Wayne F .; "Adsorption of Surfactants on Montmorillonite," Clays and Clay Minerals, Pergamon Press (1970), Vol. 18, pp. 97-105;

Hoover, M. F .; and Butler, G. B .; "Recent Advances in Ion-Containing Polymers", J. Polymer Sei, Symposium No. 45, 1-37 (1974);

Jackson, Kern C; "Textbook of Lithology," McGraw-Hill Book Company (1970), (Library of Congress Catalog Card No. 72-958LO), pp. 95-103;

Theng, B. K. G; "The Chemistry of Clay-Organic Reactions", John Wiley and Son (1974), (Library of Congress Catalog Card No. 74-12 524), pp. 1-16;

Veley, C. D .; “How Hydrolyzable Metal Ions Stabilize Clays to Prevent Permeability Reduction ", SPE-2188, 43rd Annual Fall MeMing of SPE of AIME, Houston, Texas, USA (29.9-2.10.1968);

Milchem Incorporated, "Milchem's Shale-Trol Sticky Shale Can't Stop You Anymore, "DF-5-75 IM;

Chemergy Corporation, “Maintain Maximum Production with PermaFIX and PermaFLO Treatments for Clay / Fine and Sand Control ".

However, the exchange of other ions for sodium in clay is only a temporary expedient. In the Making a borehole allows the presence of sodium ions in the water of the Formation that sodium ions in turn quickly replace hydrogen, potassium, ammonium or calcium ions. The result is that the clay is restored to its swelling or dispersible form, so that it is available again for damage if extraneous water is introduced. In the U.S. Patent 3,382,924, column 3, lines 45-75 and column 4, lines 1-3, replace calcium ions of sodium ions used in nuclear clays (lines 51-53). The calcium ions protect the core (Lines 54-57). If treatment is stopped (lines 58-63), the sodium chloride salt solution (Line 64) the calcium ions are replaced in turn, and the core becomes in terms of flow in stage 7 (Lines 65-68) contracted sharply as indicated in line 75, column 3, and lines 1-3, column 4.

Since simple cations can easily be exchanged again and the treatment is not permanent, Efforts have already been made to avoid treatment with hydrogen, potassium, or calcium Ammonium ions (and probably some other ions as well) to improve. Were more successful organic, polycationic polymers or complexes.

The most outstanding of these were ZrOCb and Al (OH) _x CIy. In the aforementioned US Pat. No. 3,382,924 and the literature sections Veley, C. D, "How Hydrolyzable Metal Ions Stabilize Clays to Prevent Permeability Reduction", the use of ZrOCl ₂ in the polycationic form of ZrOCl ₂

described, which is explained in this reference is hydroxylaluminum reaction products of HCl and Al (OH) ₃ . with the formulas ranging from Al (OH) _u Clu to (Al (OH) I ₇ ClOj are in US Patents 36 03 399, 38 27 495, 38 27 500 and 38 33 718 and in the reference by Coppel, Jennings and Reed, "Field Results From Wells Treated with Hydroxy-Aluminum".

The inorganic, polycationic polymers are complexes, soft in the control of the Migration of fine particles and swelling clays are very effective. However, there are limitations in In several respects, hydroxy aluminum compounds require a post-in-place set time in the presence of sound. This setting time is a disadvantage as during this Waiting time setup and production times are lost. Hydroxy aluminum compounds can only do one withstand a limited amount of carbonate material in the formation. Hydroxy-aluminum compounds can also be used be removed by subsequent treatment of the formation with acid. Zirconyl chloride is limited in the pH range of the fluid for putting in place and can be through Acid can be removed again under certain conditions. For other types of clay treatments it will see US Pat. No. 3,741,307.

Another treatment for controlling the undesirable effects of swelling clays and migrating fine particles is the use of organic cationic surfactants. If the organic content of the cation is sufficiently large, the organic cation is not easily replaced. Reference is made to the documents of Hower, Wayne, F., "Influence of Clay on the Production of Hydrocar- y> bons" and "Adsorption of Surfactants on Montmorillonite." Cationic surfactants, however, have a tendency to wetting the oil into the formation, and this is viewed by certain circles as an advantage, see JH Barkman's reference, "An Oil Coating Process ...". However, many petroleum experts consider oil wetting of the formation to be disadvantageous because it inhibits the production of oil and accelerates the production of aqueous fluids, see JW Graham's reference, "Influence of Propping Sand Wettability of Productivity of Hydraulically Fractured Oil Wells."

Furthermore, US Pat. No. 3,179,171 discloses the use of organic, polycationic compounds Known with a molecular weight of over 1000 5n, optionally together with saline solution or an acid can be used. However, the polycationic compounds used here have none cationic central atom in the form of nitrogen, phosphorus or sulfur, such as those according to the invention polycationic polymers used, but those used in this prior art Polymers contain built into the polymer, monovalent, cationic salts, which by opening the Anhydride ring were obtained by reaction with aqueous alkali solutions. Also in this publication nothing says that a permanent treatment can be achieved thereby, d. that is, after a Treatment with the Polymeirsat also fresh water can be fed back to the clayey soil e> can without clogging by swelling and dispersion of the clays contained in the formation occurs.

The object of the invention is to avoid the disadvantages of the previously known methods and to provide an improved one and simple method of stabilizing clay and other fine particles against dispersion and to find sources as a result of exposure to water.

The method according to the invention, as described in more detail in claim 1, is used to achieve this object is marked

The invention further relates to the use of such a method when breaking up earth formations, with an additional classified, solid, particulate Material is pumped into the borehole.

In a further application of the method according to the invention, a pressure is created in the borehole maintained adjacent to a formation in the wellbore which is greater than the fracture pressure of the neighboring formation.

The invention further relates to a treatment composition for carrying out the method, which is characterized in that it contains about 0.01 to 25 vol .-% of at least one of the in claim 1 contains specified compounds.

When carrying out the process according to the invention, an organic, polycationic polymer, as previously defined, brought into contact with the clays until the organic, polycatonic polymer has replaced the clay cation, which is normally a sodium ion, and the clay is converted into a more stable form, which has a much lower probability of swelling or Has hiking.

The organic, polycationic polymers of the invention have several advantages. You can at can be used for all types of formation regardless of carbonate content. They are acid resistant, d. that is, the formation can later be treated with acid without affecting its clay-treating ability destroy. They are available in aqueous solutions including a wide range of salt solutions and acids To put in place. Treatment with organic, polycationic polymers is practical continuous. The organic, polycationic polymers are resistant to removal Very resistant to salt solutions, oils or acids. Oil wetting of the formation can be avoided. They can be adjusted to withstand the pH range. Furthermore, no setting time is required, and studies have shown that only a time of less than 1 minute is required for complete adsorption on the clay formations with very low permeability can be treated. The retention high permeability after the treatment of clays and fine particles can be achieved. Adaptation to wide temperature ranges of the formation is possible. The polymers were examined at temperatures from 21 to 149 ° C, but it is believed that the range is still can be wider.

There is a wide range of uses for the organic polycationic polymers. These uses include the use of the organic polycationic polymers alone as primary treatment tool or as an adjunct to other treatments.

According to the invention, the application basically comprises a certain class of organic.

polycationic polymers and processes for their Contribution. The polymers have a molecular weight above about 1000 and preferably above 1500 up to about 3,000,000, and preferably less than about 100,000. The organic, polycationic polymers can be used in any earth formation or permeable mass containing clay and wherein swelling of the clay is a problem could represent. The polymers can be used to treat both naturally and artificially solidified Structures or formations are used.

Any suitable method of application may be used in view of the description given will. For some applications such as surface structures or exposed structures, it can be advantageous to spray the polymer only onto the permeable mass. The essentials The feature is the contact between the clay particles to be treated and the polymer in a preferred one Embodiment, a carrier fluid is used. A preferred carrier fluid is water or an aqueous medium. The water can contain other ingredients contain which do not significantly interfere with the dispersion or dissolution of the polymer in the medium. The water carrier can be gelled or thickened for certain applications. Such ingredients or Additives can be salts, mineral acids, organic acids with low molecular weight, surfactants Agents, wetting agents or coupling agents such as silanes or conventional ones, for consolidation treatments, Stimulatory treatments or additives used in drilling oil wells. The carrier fluid can also be a normally liquid, polar-substituted hydrocarbon such as an alcohol be. Usually a polar hydrocarbon is required to keep the polymer within the support disperse or dissolve satisfactorily. Under certain conditions, the polymer dispersed or emulsified in a non-polar carrier liquid. The carrier fluid or the carrier liquid preferably has a boiling point in the range of about 25 to 200 ° C and a viscosity of less than about 10 cP (centipoise). Fluids or liquids with a higher viscosity can be used for certain applications may be used, however, they are generally because of pressure or pumping requirements not practical. The organic, polycationic polymer should be in the carrier fluid in a Concentration within the range of about 0.01 to 25% by volume, based on the carrier fluid. Lower or higher concentrations can be used, but generally they are not practically.

A preferred aqueous carrier fluid is a saline solution containing from about 0 to 40 percent salt or up to the saturation limits at the application temperature. The preferred salt concentration is about 2 to 12% by weight, but concentrations up to about 35% can be used, as can fresh Water. The salt can be an alkali metal salt, alkaline earth metal salt, Be the ammonium salt or a mixture thereof. Such salts include the halides, sulfates, Carbonates, oxides or mixtures thereof. The halides of potassium, sodium, magnesium, calcium, Ammonium or mixtures thereof are preferred in terms of economy and solubility Aqueous acids at approximately the same concentrations can also be used. These acids include hydrofluoric acid, hydrochloric acid, nitric acid, phosphoric acid, and sulphurous acid Sulfuric acid. Low molecular weight organic acids such as acetic acid and sulfonic acids can also be used under certain conditions. Conventional additives like Inhibitors, surfactants, coupling agents, wetting agents and other agents can where this is desired to be applied and especially in

in cases of using the organic, polycationic Polymerizats in conventional treatment procedures. The carrier fluid preferably contains salts or acids which cause shrinkage or prevent swelling until the polycationic Polymerisat has treated the clay particles. Usually, the treatment is practically instantaneous with the Contact between the formation and the treatment fluid. The carrier fluid and formation become by injecting the carrier fluid into the formation, applying the fluid to the formation, or flowing it of the fluid through the formation or behind the formation in such a way that only one minimal disturbance or resuspension of individual particles within the formation is caused in The treatment procedure according to the invention is therefore particularly advantageous when the Permeability or permeability is low and the maintenance of a maximum permeability or permeability Permeability is a critical characteristic.

In chemical injection processes such as sealing leaks in dams, mines, tunnels, foundations and the like - see US Pat. Nos. 29 40 729, 28 01 984, 28 01 985 and 33 34 689 - exist Cases in which the permeability decreases and the formation decreases the uptake of the chemical injection agent Denied This is usually due to the disturbance of the pH value or due to osmotic Disturbances caused by the introduction of an extraneous water (chemical injection agent) into the Formation are conditioned. By pretreating the injection hole with an organic, polycationic Polymerizate's permeability can be retained, leaving sufficient chemical injection agent can be injected and spread in a sufficiently large radius to seal leaks can.

A common problem when creating gas, oil and / or water wells is this Collapse of the soft formation around the

so borehole and the production of sand. Since the production of sand is very undesirable Several means have already been proposed to stop sand production, one means is gravel or gravel. Gravel pack. Gels and / or salt solutions are applied around the gravel or crushed stone, usually sized sand or particulate matter, in place and place to wash around the wellbore during the break in production.

In one way of working, the gravel or crushed stone or sand is brought to settle and compacted A liner or screen is then flushed into the borehole and across the formation The packing sand now holds back the formation sand, and the sieve holds back the packing sand. this enables the production of fluids that are free of sand. However, if the gravel or crushed stone is in place and place is pumped, the loose solids pressed back into the formation and form a compact

tation front between the formation and the packing sand. This front, especially if it is clay often restricts the flow of fluid into the wellbore after the gravel pack is removed is in place. The use of organic, polycationic polymers in a Pre-rinsing in the carrier fluid for the gravel or ballast packing or in a fluid after the Ballast or gravel packing is in place, the loss of permeability in the compaction front turn it off or make it less powerful. Furthermore, organic, polycationic polymers, which were washed out over the neighborhood of the gravel or gravel pack, the hike of fine particles in the gravel or crushed stone packing, such fine particles often the Clog the gravel packing.

Hydraulic fracturing with sand or the sand packing of any cavity may be similar to a gravel pack except that the grain size may be different. the Use of organic, polycationic polymers in connection with sand fracturing gives the same favorable result.

In sand solidification or sand consolidation, hard, hardening resins are used to bond Grains of sand used together. The formation sand itself can be treated like this or it can be a sand coated with a pre-resin can be used as a sand pack. The use of organic, Polycationic polymers in connection with a sand solidification can prevent the back migration of fine particles and clays in the bulk of the sand will prevent solidification and the clogging effect a compaction front, if one should form.

In secondary extraction processes, where water flushing or water flooding for the extraction of oil are used, there is a good chance that the only water available for injection will be in the Injection wells cause swelling of clay and / or migration of fine particles that cause the Injection boreholes can clog, causes. A pre-treatment of injection wells with organic, polycationic polymers before flooding with the suspicious water can cause a Prevent damage from migration of fine particles and swelling of clay. This is in the immediate vicinity The neighborhood of the borehole, where permeability is very important, is very special Importance. The treatment can be used to improve the water wetting properties of a formation to change or any reduction in the (^ permeability of any formation as a result to prevent oil wetting of the formation where clay could be a problem.

Certain formations are along with substances that are removed or by contact with water be weakened, of course cemented or consolidated. As long as only hydrocarbons are produced, there is little trouble with these boreholes. However, if the water level rises in the course of production and the water along with the Hydrocarbons is extracted, the production or extraction of sand sometimes begins Situation so bad that a collapse of the borehole is the result. If the material is for the Cementing the fonnation is clay, a treatment of the neighborhood of the borehole before the Water breakthroughs prevent the production of sand and / or the collapse of the borehole.

When skirting oil and gas wells, the skirting or casing is required to be closed perforate or drill a section of an open hole below the enclosure or housing, to complete the well and begin production. An accident during this operation of the Borehole prefabrication is when the fluid in the borehole compromises permeability as it often penetrates the formation when it is opened. The borehole can be an open borehole or be completed by perforation using form charges or spheres. As a Organic, polycationic polymers have the purpose of being part of the completion fluid Preventing permeability damage if the pressure in the borehole becomes higher than that Formation pressure and the wellbore fluids enter the formation.

Acidification is a common technique in the art of improving well production. In the Acid is pumped into the formation for the purpose of enlarging the pores and therefore increasing the permeability or To increase permeability. Often hydrochloric acid is found in carbonate formations such as limestone and Dolomite is used, and hydrofluoric acid solutions are often used in sandstone formations. jo However, in some formations, acid treatment loosens the fine particles so that they migrate and cause clogging. A feature of these formations is that acidification improves the production, however, a decrease in the production rate soon occurs when fine particles are in clogging positions hike. The use of organic, polycationic polymers before, during and / or after acidification minimizes the conveyance of fine particles.

Hydraulic fracturing is another common technique in the art for improving the Well production. The wellbore is pressurized until the formation bursts and the the resulting fracture exposes large areas of the formation surface. The fractures are normally prevented from growing together by pumping sand into the fracture, however, does occur Fracturing fluid that penetrates the fracture surface often interacts with the clays and degrades the Permeability This damage is especially critical when the permeability is low d. H. at values of about 10 millidarcy to 0.1 millidarcy. The usage of organic, polycationic polymers in connection with breaking processes has proven to be very successfully exposed

It is much better to avoid damage from swelling clays and / or wandering fine particles prevent rather than correcting or repairing the damage as it occurs. Much of this damage are irreversible. In the cases in which damage however, the use of organic polycationic polymers as may have already occurred primary treatment agent in conjunction with other treatments a large part of the lost Restore permeability.

During the drilling process, with boreholes, especially air and gas drilled boreholes, there are often annoyance from swelling and swelling of

R ₁ -Z ⁺ -R ₃
R ₄

CH ₃ OSO ₃ -

CH ₃ OSO ₃ -

Formations penetrated by the borehole. These formations contain clay minerals, the slipping when wetting with aqueous fluids such as fog or foam drilling Cause formation, which often creates the risk of the drill chain and / or the drill bit sticking in the hole is caused. Some of these formations are called slate clay. The treatment and / or impregnation of these formations with the composition according to the invention can Avoid the risk of the formations swelling or swelling. Treatment can also are used in drilling operations or completions where two-phase fluids, such as emulsions, Foam, mist, smoke or gaseous dispersions, haze or slurries are used.

The organic, polycationic polymers of the following formula used according to the invention may or may not contain other atoms such as oxygen or nitrogen. The organic leftovers can be homocyclic or heterocyclic; that is, they can be other atoms such as oxygen or nitrogen included or not included. Furthermore, the organic radicals can be substituted or unsubstituted Alkyl radicals, aryl radicals, or combinations thereof, each radical being up to 40, and preferably up to Contains carbon atoms.

The following compounds are examples of the preferred polycationic polymer classes:

(1) If Z = sulfur, a sulfonium polymer:

-R ₁

S ⁺

X "

wherein the substituents have the meaning given in claim 1, can in general as primary polymers with nitrogen or phosphorus or as ternary polymers with sulfur as Central atom in an aliphatic, cycloaliphatic or aromatic chain.

The ratio of cationic atoms to carbon atoms is preferably about 1: 2 to 1: 36, and the molecular weight is above about 1000. The organic, polycationic polymer is polar and therefore it is generally in polar solvents or carrier fluids such as an aqueous medium or an alcohol soluble or easily dispersible. An alcohol can be used as a carrier fluid, if there is contact between water and the permeable mass or formation to be treated should be avoided. Examples of these polycationic polymers include polyethylene amines, polyvinylpyridinium salts or polyallylammonium salts.

If the polycationic polymers used according to the invention _{contain a cycloaliphatic radical R 1} , the cation (Z) derived from nitrogen, phosphorus or sulfur and the organic radical (R2) can be incorporated into the internal system.

The anion X of the polycationic polymers can be, for example, a halogen, nitrate or sulfate ion. An alcohol can also be used as the carrier fluid. The organic or hydrocarbon radicals can be straight-chain, branched or cyclic, aliphatic radicals, aromatic radicals, unsaturated Radicals, substituted radicals or combinations thereof. The organic radicals can be homoaliphatic or heteroaliphatic, that is, they can

(2) where an example is derived from the following monomer:

H ₂ C = CHCO ₂ CH ₂ CH ₂ S (CHj) ₂ CI

Poly-2-acryloxyethyldimethylsulfonium chloride;

R, = 2-acryloxyethyl, R ₂ = methyl, R ₃ = methyl, R ₄ = absent and X = chloride;

if Z = phosphorus, a phosphonium polymer:

-R-

R ₂ -P ⁺ -R ₃

R ₄

being an exemplary monomer

H ₂ C

CH-CH ₂ P (C ₄ H ₉ ) ₃ C!

45

(3) is glycidyltributylphosphonium chloride; with
_{R 1} = glycidyl, R 2 = butyl, R ₃ = butyl, R ₄ = butyl and X = chloride;

when Z is nitrogen, quaternary ammonium polymers;

(3 a) where an example of a quaternary, integral alkyl polymer is:

CH ₃

-CH ₂ -CH ₂ -N ⁺

CH ₃

Polydimethyläthylenammoniumchlorid, and another example of a polymer:

CH ₃ CH ₃

-N ⁺ -CH ₂ -CH ₂ -N ⁺ -CH ₂ -CH ₂ -Ch ₂ -CH ₂ -

CH ₃ CH ₃

namely the condensation product of Ν, Ν, ΝίΝ'-tetranietliylethylenediamine and 1,4-dichlorobutaii;

(3 b) Compounds with the one in the cyclic ring (3 0 compounds with one in a carbocyclic ring

built, quaternary nitrogen atom, where an example of a polymer is:

pending, quaternary groups, an example of such a polymer being:

the condensation product of 4-chloropyridine; (3 c) Connection with the one in the alkyl chain and the one Aryl radical integral, quaternary nitrogen atom, an exemplary polymer being:

Cl

-N

CH ₂ -CH ₂ -CH ₂ CH ₂ -CH

Y
CH ₂

N ⁺ he

CH ₃ CH ₃
CH ₃

the condensation product of 1- (4-pyridyl) -3-chloropropane; and another example of a polymer:

N ^H

s cr

^ N-CH ₂ -CH ₂ -PolyvinyM -benzyltrimethylammonium chloride; (3 g) Compounds with quaternary nitrogen groups attached to a polymethacrylate skeleton, an example of such a polymer being:

the condensation product of pyrazine and 1,2-ethylene dichloride;

(3d) Compounds with pendant quaternary r, alkyl radicals, an example being the following polymer is:

-CH ₂ -CH

N ⁺ he

CH ₃

CH ₃

CH ₃

Polyvinyltrimethylammonium chloride, (3 e) compounds with a cyclic backbone pending, quaternary groups, an example of such a polymer being:

60

65

Poly-l ^ -phenylene oxide ^ -methylene trimethylammonium bromide:

CH ₃

CH ₂ -C-

C = O

I he

O CH ₃

CH ₂ -CH-CH ₂ ⁺ -N-CH ₃ OH CH ₃

Poly-3-methacryloxy (2-hydroxypropyltrimethylammonium chloride);

and another example of such a polymer is:

Γ
1-

C = O
HN-CH ₂ -CH ₂ -CH ₂

CH ₃

N ⁺ cr

CH ₃

CH ₃

Polyacrylamido-l-propyl-3-trimethylammonium chloride:

(3 h) compounds with quaternary nitrogen groups hanging from a heterocyclic ring, where an example of such a polymer is:

-CH ₃ -CH

Poly-4-vinyl-N-methylpyridinium iodide;
Compounds with a heterocyclic ring which contain quaternary nitrogen groups, an example of such a polymer being:

CH ₂
-CH CH-CH ₂ -

: h ₂

ch,

cr

CH, CH,

Polymer of diallyldimethylammonium chloride.

The invention is explained in more detail in several embodiments with reference to the following examples, wherein all information in parts, percentages, ratios and concentrations, unless otherwise stated, are expressed in weight.

Examples

The test procedure for polycationic polymers is explained in more detail below:

Test cell structure

The polycationic polymers were examined in a simulated formation, soft sand, fine sand Contained sediments and clay. The test cell was packed by using a single pierced rubber stopper was inserted into a glass tube. To prevent sand from falling through, a wire mesh was made existing sieve coated with a thin layer of glass wool and attached to the top of the at the Underside of the glass tube inserted stopper arranged. Next up was to prevent a Blockage of the sieve by packing a layer of sized sand on top of the sand pack Stopper and sieve packed. The next layer was the sand pack, with the sand pack being the Test medium was. It was packed in a moist state so that the sand, the fine parts and the Clay adhered to one another in such a way as to avoid the formation of layers of the packing. Finally a layer of pure sand was used to protect the sandpack from particulate contamination Applied over the two lower layers.

The sand pack consisted of 85% by weight of the clean

Sand (Oklahoma sand no. 1) with a mesh size of 0.21-0.088 mm, 10% by weight quartz with a mesh size <0.053 mm, 5% by weight Montmorilloni (Wyoming bentonite) with a surface area of about; 750 m ² / g and 0.75 ml of salt water, which was sufficient for a detectable moisture.

The cell dimensions were: inside diameter! of the tube 2.32 cm, inner cross-sectional area de: tube = 43 cm ² ; Height of the sand packing sow

ίο Ie = 8.04 cm; Tube volume (sand packing area) = 33.09 cm ³ ; Porosity = about 30%; and height of the pure sand column (Oklahoma sand # 1 (both the top and bottom columns) = 1.51 cm.

The test cell structure was kept constant from test to test. The above: Values are the mean values of several] cells from consecutive test examinations.

Average values for some flow rates on test cells

temperature 25th 23.9 Stream flow ( ⁰ C) 62.5 (ml / min) 93.3 jo test sequence or 13.67+ + K = 140.3 md step 24.25 35 1 41.50 Way of working 3 flowing fluid (liquid) 4th Standard saline solution 5 Treatment solution 40 6 Standard saline solution fresh water 8th 15% HCl 9 fresh water Diesel oil fresh water Diesel oil

The initial stage of using standard salt solution served to calibrate the sand pack. As fresh: Tap water was used. Freshness; Water and deionized water are different from each other Properties for swelling of clay approx

so equivalent, and they are the critical test of whether or not a stuff was effective in treating νυη clay.

The 15% HCl treatment stage was used to test the lasting effect of the clay treatment chemistries alkalis in the presence of acid.

The stages diesel oil - fresh water - diesel oil are used ten to study the lasting effect of the clay treatment chemical in the presence of oil If the diesel oil rate is higher than the water rate, the system was considered to be wetted by water.

Composition of the standard saline solution

salt

ÜCW .- "i

NaCl
CaCl,
MgCI, ·
water

6 11.0

7.5

0.55

0.42

91.53

230 212/35:

Pressure and temperature

18th

Properties of the Berea sandstone core *)

Beam analysis

Average value (%)

A pressure of 3.52 atm was maintained on the reservoir during all treatment stages.

The reservoir had a heating mantle that held the desired temperature for the test liquids maintained. A heating tape was placed on the test cell used

Berea- ι ο Cores used with the core and reservoir heated to test temperature. The 5.1 cm long core rested on a pad of sand with a grain size of 0.25-0.42 mm and a height of 1.9 cm and was protected from inevitable contamination by a buffer layer of sand with a Grain size of 0.25-0.42 mm at a height of 1.9 cm on the top with an overlying layer Sand (Oklahoma # 1) protected at a height of 0.64 mm. These layers of sand provided about 2% of the specific resistance of the cell.

Table I.

Names for the clay treatment chemicals and solutions used in the examples

quartz

dolomite

Kaolinite

Illite montmorillonite and

Mixed layer clays

Other analyzes

Acid solubility

Porosity 79.0

4.0

11.0

3.7 2.3

2.8% 21.96%

Permeability (permeability) 2.8 md

*) This is an average of 16 cores and it is considered to be representative of the one used for the test cores Sandstone block viewed.

Chemical name

comparison
OHAl

ZrOCl ₂

PDMDAA

EDCAM

BDCTMDA

DMAECH

BDMAECH

DMABCD

DEAPA

TADATO

TADATOQ

HBEOTO

description

there was no chemical to treat clay

Hydroxyaluminum compounds with the following proportions in the examples:

Al ₂ (OH) ₅ Cl

Zirconyl chloride, by analysis = ZrOCl ₂ · 8 H ₂ O

Polyethyleneimine, a polymer of aziridine

Polydimethyldiallylammonium chloride

Standard saline solution

fresh water

Tetraethylene pentamine

Condensate of ethylene dichloride and ammonia

Condensate of ethylene dichloride and ammonia, quaternized with methyl chloride

Triethylenetetraamine

Condensate of 1,4-dichlorobutene with Ν, Ν, Ν ', Ν'-tetramethylethylenediamine

Condensate of dimethylamine with epichlorohydrin

Condensate of dimethylamine with epichlorohydrin, branched with ammonia

Condensate of dimethylamine with 1,4-dichlorobutane

1,6-hexanediamine

Diethylaminopropylamine

Condensate of triethanolamine / diethanolamine / tall oil

TADATO, quaternized with CH ₃ CI

Hexanediamine distillate residue, reacted with ethylene oxide and esterified with

Tall oil and acidified with hydrochloric acid

Table II

Flow test of clay treatment at 23.9 ° C

example

I.

Treatment solution
Chemical or polymer
Molecular weight ¹¹ )
Concentration (%)
solvent

Cf. Cf. PDMDAA PDMDAA PDMDAA - - 37,000 37,000 37,000 0 "θ 4th 2 0.4 SB SB FW FW FW

ml 27 36 277 1.0 ") - 2 3 37,000 20th 4th 8th 11th 12th 15.2 - 500 - 2 62.5 62.5 - continuation 300 13.4 12.3 SB 13.4 PDMDAA - 500 example example 50,000 PDMDAA PDMDAA 100.0 500 I. 6th 14.4 2 37,000 37,000 3.5 ^a ) calibration 400 100.0 100.0 100.0 SB 2 0.4 5.0 ") 9 Standard saline solution (ml / min) 500 14.6 17.1 23.1 SB SB Flow tests (%) of the calibration value 99.2 100.0 82.1 12.8 PDMDAA solution 99.2 49.3 88, i 26th 32 75,000 Standard saline solution 100.0 70.1 86.1 102.8 73.1 2 Treatment solution - 0.6 94.3 104.2 85.1 100.0 SB Standard saline solution - 73.6 39.8 fresh water 91.7 100.0 15.2 15% HCl 7th 100.0 fresh water 79.7 Table II (continued) PDMDAA PDML) AA 85.9 100.0 37,000 indicated volume had been delivered. 31.5 0.4 : 10% stated. 92.1 Treatment solution ml SB 81.6 Chemical or polymer 500 82.9 Molecular weight ¹¹ ) 300 14.6 68.4 Concentration (%) 500 solvent 500 calibration 400 100.0 Standard saline solution (ml / min) 500 80.8 Solvent for organic, polycationic polymers Flow tests (%) of the calibration value I.
I ^a ) = The flow stopped before the full one. 101.4 j solution ; t ^b ) = The molecular weights are on 4 68.5 13th S standard saline solution 1 Table III 71.2 93.3 I treatment solution I change the temperature and the 1st 61.6 jj standard saline solution PDMDAA I fresh water 37,000 I 15% HCl I test temperature ( ⁰ C) 0.4 Β fresh water $.] Treatment solution SB | i; Chemical or polymer "'■ molecular weight ¹¹ ) 38 • Λ concentration (%) example ; solvent 10 calibration 62.5 ! Standard saline solution (ml / min) Cf. - 0 SB 23

21

Fortsei /, une

ml example 500 IO Flow tests (%) of the calibration value 300 solution 500 Standard saline solution 500 100.0 Treatment solution 400 - Stancard saline solution 500 - fresh water 15% HCl - fresh water _

11th

12th

100.0 100.0 100.0 50.0 90.6 96.1 111.5 106.0 135.5 126.9 111.9 147.0 40.0 93.8 ^il J 39.5 100.0 156.3 131.5

Table III (continued)

example

14th

17th

Test temperature ( ⁰ C)

Treatment solution Chemical or polymer Molecular weight ¹¹ ) Concentration (%) Solvent

calibration
Standard saline solution (ml / min)

62.5

93.3

62.5

18th

45

19.6

62.5

PDMDAA PDMDAA PEI PDMDAA 37,000 37,000 20,000 37,000 0.4 0.4 0.1 0.4 15% HCI 15% HCl 15% HCl 3% CaCl,

29.0

Flow tests (%) of the calibration value ml 100.0 ;for 100.0 100.0 is this alternating Ethylene groups 22nd 100.0 ) 20,000 ^C ) solution 500 63.9 after 62.6 98.0 65.5 0.1 Standard saline solution 300 136.1 113.3 132.7 100 ml of fresh water as a result of the low flow rate 75.2 SB Treatment solution 500 130.0 Organic, polycationic polymers, 120.0 167.3 20th 21 82.8 4th Standard saline solution 500 - groups exist - - which generally look 20.0 fresh water 400 - - · - EDCA EDCAM 79.3 15% HCl 500 ") = A solution of 3% HF and 12% HCI was used instead of the 15% HCI 1 used. example ) 1 500 ') 2 000 ^a ) fresh water ^b ) = The molecular weights are within an error limit of ± 10% Treatment solution specified. For PDMDAA 18 19 0.36 0.25 Number through Average molecular weight indicated Chemical or polymer PEI no more precise information is available. SB SB "■ ') = The flow investigation was Molecular weight EDCA EDCA 4th 4th canceled. Table IV Concentration (%) 7 500 ^{; l} ) 25 000 ": solvent 0.25 0.28 and amine Solution miltel-pl 1-Werl SB SB 4 4 23 EDCAM PEl 2,000 ^b 0.25 SB 7th

24

continuation

ml example 19th 20th 21 22nd 23 500 18th calibration 300 20.8 23.0 17.2 17.6 23.6 Standard saline solution (ml / min) 500 23.2 Flow tests') (%) of the calibration value 500 solution 400 100.0 100.0 100.0 100.0 100.0 Standard saline solution 500 100.0 59.6 108.7 110.5 110.8 101.7 Treatment solution 80.2 56.7 104.3 98.8 102.3 100.0 Standard saline solution example 90.5 46.2 139.1 130.8 130.7 35.6 fresh water 24 100.9 31.3 50.0 60.5 82.4 14.8 15% HCI 56.0 74.5 156.5 157.0 210.2 114.4 fresh water PEI 120.7 Table IV (continued) 20,000 ') 1.0 26th 27 28 29 30th SB 25th Treatment solution PEI PEI PEI TEPA TETA Chemical or polymer PEI 300 ') 1 200 ') 100,000 ') 189 146 Molecular weight 20,000 ') 0.3 0.3 1.0 1.0 1.0 Concentration (%) 1.0 SB SB 15% HCl SB SB solvent 15% HCl

calibration 21.4 Flow tests ^d ) (%) of the calibration value ml 25.4 21.4 23.5 21.9 - 22.6 - 26.2 - Standard saline solution (ml / min) solution 500 100.0 - - - Standard saline solution 300 7.5 is not included. Treatment solution 500 6.1 100.0 100.0 100.0 100.0 100.0 the chloride counterion is not included. 100.0 Standard saline solution 500 51.2 123.8 102.1 11.4 115.0 139.8 fresh water 400 15.0 70.0 126.2 110.6 25.1 95.1 114.5 15% HCI 500 94.5 146.7 139.0 1.1 2.8 ^d ) 0.4 fresh water is to about ± 2500, - 58.9 22.6 ^J ) = This molecular weight - 3.9 4.7 ^h ) = this molecular weight exactly, wöbe i the chloride counterion is accurate to about ± 500, where * l = The spread of this molecular weight is not known ^u i = These tests were carried out at 62.5 ⁰ C.

Table V

Various organic polycationic polymers

Treatment solution Chemical or polymer Molecular weight Concentration (%) Solvent Solvent pH

example 32 33 34 35 31 DMAECH DMAECH DMAECH DMAECH BDCTMDA 1 750 ^a ) 7 50O ^b ) 7 500 ") 7 500 ^b ) 1500 0.37 0.37 0.185 0.037 0.5 SB SB SB SB SB 4th 4th 4th 4th 4th

continuation

26th

lic isjiicl

31 34

calibration ml 23.6 Standard saline solution (ml / min) 500 Flow ^{tests c} ) (%) of the calibration value 300 solution 500 100.0 Standard saline solution 500 114.4 Treatment solution 400 111.9 Standard saline solution 500 150.4 fresh water 74.2 15% HCl 154.3 fresh water

21.2 19.4

22.2

30.3

100.0 100.0 100.0 • 100.0 - 109.4 108.8 117.6 113.2 - 121.2 134.5 131.1 122.1 159.4 182.0 155.4 6.9 44.8 93.8 82.4 184.0 156.2 128.8

Table V (continued)

example 37 38 39 40 41 36 Treatment solution DMAECH BDMAECH DMABDC HXDA DEAPA Chemical or polymer DMAECH 7 500 ^b ) 17 500 ^h ) 1,500 116 130 Molecular weight 1 750 ") 0.37 0.37 0.39 1.0 1.0 Concentration (%) 0.37 5% HCl SB SB SB SB solvent 5% HCI - 4th 4th 4th 4th Solvent pH -

calibration
Standard saline solution (ml / min)

Flow tests ¹ ') (%) of the calibration value

26.3

35.3

") = The molecular weight spread is about ± 250. ^B ) = The molecular weight spread is about ± 2500.; - LyicSc lcStS" would result at 62.5 ".

Solution ml 100.0 100.0 100.0 Standard saline solution 500 76.0 103.1 79.9 Treatment solution 300 85.2 106.2 130.7 Standard saline solution 500 108.7 124.9 112.1 fresh water 500 10.9 85.5 34.6 15% HCl 400 117.5 113.3 112.1 fresh water 500

23.1

22.2

23.0

100.0 100.0 - 100.0 - 108.2 122.5 - 114.8 _ 116.9 104.9 104.4 124.2 2.6 0.4 51.5 160.2

Table VI

Treatment of clay with inorganic, cationic polymers at 23.9 ⁰ C

Example 42 43

Treatment solution
Chemical or polymer
Molecular weight
Concentration (%)
solvent

Cf.

3% CaCl ₂ HOAl

2.5
2% KCl

ZrOCl ₂

1.2
2% KCl

27

Fortsolzunu

Example 42

44

calibration ml 11.9 - 15.2 15.8 Standard saline solution (ml / min) 500 - Flow tests 300 solution 300 100.0 100.0 100.0 Standard saline solution 100 74.0 83.3 68.4 3% CaCl ₂ 100 60.0 61.8 41.1 deionized water - - 42.8 34.8 Treatment solution 300 - 43.4 29.7 Rinsing 300 - ~; - Endurance 300 38.0 40.7 31.6 3% NaCl 300 1.1 44.1 31.6 deionized water 27.6 25.3 15% HCl 1.0 0.6 deionized water ") = not determined. ^b ) = 18 hours.

Table VI

Organic, polycationic polymers as clay treatment agents in a carbonate formation

Test sand composition

Materia!

ücw .- 'K.
Pack A

Pack B

Sand, grain size 0.21-0.088 mm, marble chips, grain size 0.21-0.088 mm Quartz, grain size <0.053 mm montmorillonite

75 0 10 85 10 10 5 S.

example

45

Treatment solution ml Cf. 2.8 - PDMDAA PDMDAA Chemical or polymer 500 - - 37,000 37,000 Molecular weight 300 - 0.4 0.4 Concentration (%) 500 FW SB SB solvent 500 calibration 400 A. A. B. used sand 500 15.0 13.6 3.2 Standard saline solution (ml / min) Flow tests (%) of the calibration value solution 100.0 100.0 100.0 Standard saline solution - 105.9 93.8 Treatment solution - 122.1 96.9 Standard saline solution 125.0 109.4 fresh water 76.5 - 15% HCl 169.1 fresh water

29

Table VIII

Impairment of water wetting by clay stabilizing agents

ml example 49 50 51 52 500 48 38 33 14th 16 Extension of example 500 32 Treatment solution 500 BDMAECH DMAECH PDMAA PEI Chemical or polymer DMAECH 0.37 0.37 0.4 0.1 Concentration (%) 0.37 SB SB 15% HCI 15% HCI solvent SB Flow tests (%) of the calibration value in the original example Fluid 68.2 72.2 94.4 84.1 Diesel oil 139.2 16.8 24.2 13.3 83.7 fresh water 24.1 61.7 72.2 85.5 92.9 Diesel oil 132.1

Table VIIIA

Clay treatments with organic, polycationic polymers that contain oxygen bonds

example

52 A 52 B 52 B

Treatment solution Chemical or polymer Concentration (%) Solvent

TADATO TADATO HBEOTO 0.86 0.7 0.68 SB SB SB

calibration ml 23.0 27.0 19.7 Standard saline solution (ml / min) 500 Flow tests (%) of the calibration value 100 solution 500 100.0 100.0 100.0 Standard saline solution 500 89.1 81.5 56.9 Treatment solution 400 95.7 98.5 93.4 Standard saline solution 500 115.2 136.3 136.0 fresh water 500 46.1 33.7 39.1 15% HCl 500 140.4 118.5 181.7 fresh water 5öö 110.9 84.4 97.5 Diesel oil 33.9 26.7 86.3 fresh water Over 3.5 X (), 7 86.8 Diesel oil

Table IX

Test investigations for tone stabilization in Berea kernels, pressure: 3.52 atü; Tcmp. = 62.5 ° C

example

53 54 55 56

Treatment solution

Chemical or polymer none none

Concentration (%)

Solvent Comp. Cf.

ZrOCl ₂ ZrOCI ₂ ZrOCl ₂ 1.2 1.2 1.2 2% KCl 2% KCl 4% KCl

Forlscl / unii

32

example

53 54

56

calibration ml Standard saline solution (ml / min) 300 Flow tests (%) of the calibration value 200 solution 300 Standard saline solution 300 Treatment solution 250 Standard saline solution 300 fresh water 300 15% HCI 300 fresh water 300 Diesel oil fresh water Diesel oil

14.0

100.0

0.5

11.8

27.0

24.8

100.0 100.0 100.0 - 39.3 145.2 ") - 3.7 28.2 - 48.0 19.8 35.6 - 46.4 211.7 ^a ) - 100.8

10.6

100.0

Standard salt solution was used instead of Irish water at this stage of the flow test, so that the increase

the permeability could be measured by acidification. ^h ) = 100 ml of 5% HCl were sent through before the treatment solution.

^c ) = 100 ml of 4% KCl solution were sent through before the coating solution.

^d ) = After the injection of 85 ml of the treatment solution, no detectable flow rate was found. °) = The treatment solution was followed by rinsing with 100 ml of 1% KCl solution.

Table IX (continued)

Treatment solution
Chemical or polymer
Concentration (%)
solvent

example 59 60 61 58 OHAl PDMDAA PDMDAA ZrOCl, 2.5 0.4 0.4 1.2 FW SB SB 3% HCl

calibration ml 17.2 16.0 19.0 8.3 Standard saline solution (ml / min) 300 Flow tests (%) of the calibration value 200 solution 300 100.0 100.0 100.0 100.0 Standard saline solution 300 50.0 87.5 90.5 85.5 Treatment solution «0 55.6 62.5 ^C ) 105.3 96.4 Standard saline solution 300 104.7 58.7 121.1 108.4 fresh water 300 - 4.3 16.3 38.6 15% HCl 300 - 215.6 204.2 596.4 fresh water 300 - 112.5 60.5 255.4 Diesel oil - 35.0 13.2 104.8 fresh water - 106.3 33.7 224.1 Diesel oil

The standard saline solution was used without fresh water at this stage of the flow test so that the increase

the permeability could be measured by acidification. Before the treatment solution, 100 ml of 5 ″ HCI were sent through.

Before the treatment solution, KXI ml of 4% KCl solution were passed through.

After the injection of 85 ml of the treatment solution, no discernible striations were found.

The treatment solution was followed by rinsing with K) OmI 1% KCl solution.

230 212/35

33 34

Table X

Treatments to remedy previous deleterious influences on the permeability of Berea cores

example (D) rate 66 b3 (D) 67 rate 64 rate 62 (F) 22.6 (F) 15.0 26.0 Treatment solution (F) 3.6 Cf. (F) 0.5 Cf. 0.6 Chemical or polymer Cf. (R) - - (R) 1.42 - 2.4 Concentration (%) - (F) - SB (F) 0.7 5% HCl 33.0 solvent no: (F) - VoI. (F) - Vol. (D) 29.0 Injected fluid Vol. (F) - 390 (F) - 510 (F) 15.2 Standard saline solution 480 23 155 (F) deionized water 76 example 98 102 (R) Treatment solution - 65 36 237 (F) deionized water - - 1021 (F) deionized water - - 2801 (F) deionized water - Table X (continued) 68

Treatment solution
Chemical or polymer
Concentration (%)
solvent

Injected fluid
Standard saline solution
deionized water
Treatment solution
deionized water
deionized water
deionized water

Comparison = blank or no means.

= not carried out.

Vol. = Flow rate in (ml / min).

(D) = direction of flow.

(F) = flow in the forward direction, i.e. the original direction.

(R) = flow in the opposite direction.

Pressure = 3.52 atm.

Temperature = 62.5 ° C.

PMDAA (D) rate ZrOCl - 2 rate PMDAA (D) rate ZrOCl 2 (D) Advice( 0.4 (F) 10.6 2.2 - 17, ⁷ 0.4 (F) 13.4 2.2 (F) 18.0 SB (F) 4.4 SB 0.2 (F) 0.82 5% HCl (F) 0.2 Vol. (R) 3.5 Vol. (D) 0.03 5% HCl (R) 4.3 Vol. (R) 1.9 300 (F) 8.1 390 (F) 0.02 Vol. (F) 13.0 420 (F) 29.0 96 (F) 11.4 10 (F) - 450 (F) 25.0 7th (F) 12.0 98 (F) 11.4 28 (R) - 348 (F) 25.0 92 (F) 4.0 30th 7th (F) 97 234 450 (F) 728 1008 600 (F) 1505 2705 2717

Example 69

A sample of a formation (Milk River) from a borehole near Medicine Hat, Alberta, Canada, was put in fresh water. The sample began to close at the layers in 10 seconds separate. After one minute, the edges were observed to slip or wear away; after five Minutes the sample had crumbled into a discontinuous hill.

Example 70

A sample of the formation described in Example 69 (Milk River) was placed in fresh water arranges. which contained 0.8% PDMDAA. There was no observable decay of the sample. After 24 There was a trace of separation on the stratifications after hours and after 6 months no other appearance of destruction; the sample showed no wear or slippage, and the jagged edges of the layers on the sample edges could still be distinguished very well.

Examples 69 and 70 show that PDMDAA can prevent the collapse of oil wells, which so-called "spring slate" or "slate clays" penetrate. These water sensitive formations are not infrequently and cause problems during drilling by collapsing into the borehole and closing the Drill pipe. Besides problems from getting stuck

of drill pipes, water-sensitive formations can also be drilled with holes deviating from the dimensions cause and problems inserting the bezels when the drilling is complete Examples of water-sensitive formations what problems

when drilling, inserting the bezels or when cementing wells are Milk River shale, Canada; Atoka Sands, Eastern Oklahoma; Glenrose Shale, South Louisiana; and Anwhac-Schiefer, South Texas, USA.

Table XI

Treatment with organic, polycationic polymers in a polar solvent

Treatment solution
Chemical or polymer
Molecular weight (%)
Concentration (%)
solvent

calibration ml Standard saline solution (ml / min) 400 Flow tests (%) of the calibration value 100 solvent 400 Standard saline solution 400 Treatment solution 400 Standard saline solution 500 fresh water 15% HCl fresh water M = methanol. ^a ) - ± 3700. ^b ) - ± 250. ^c ) - ± 2500.

Cf.

PDMDAA DMAECH DMAECH 37 000 ^a ) 1750 ") 7 500 ^ 0.4 0.37 0.37 M. M. M.

25.0

100.0

142.8

93.2

115.6

56.8

95.6

24.2

100.0
99.6

123.6

159.1
57.0

120.7

22.9

100.0
110.5

91.7
138.0

41.9
130.1

Table I lists the names for the clay treatment chemicals and solutions that were used in the examples.

Table II, Examples 1 through 9, are studies of polydiallyldimethylammonium chloride of various molecular weights at room temperature. the the first two examples provide comparative values of the results in the absence of clay treatment chemicals. The result of Example 2 is interesting in that hydrochloric acid is often used as Clay treatment chemical is used. Examples 3 and 4 show cases using fresh water as the carrier fluid for the clay treatment chemical. Examples 5 and 6 show that at lower concentrations of clay treatment chemicals salt in the carrier fluid (treatment solution) may be required. Perhaps there is a short response time before the clay treatment chemical can attach to the clay, and during this period a salty environment is required around the Keeping sound under control. Examples 7, 8 and 9 suggest that the optimal molecular weight is exceeded because the protection provided by the polydiallyldimethylammonium chloride with the Molecular weight decreases again.

Table III, Examples 10-17, shows the changes in temperature and solvent with organic, polycationic polymers.

Example 10 shows that clogging of the sand pack can be expected when fresh Water is introduced without prior treatment with a clay stabilizer. The main difference between example 10 and example 11 lies in the temperature.

Examples 10-17 provide a range of temperatures and solvents for PDMDAA im Comparison with Examples 1 to 9. As in the footnote

a) given for example 12, the increase in the flow rate for the fresh water phase after the Acid the dissolving of clay and fine particles by hydrofluoric acid instead of the only effect of Attributed to PDMDAA. The use of organic, polycationic polymers in Connection to RF solutions is an important application.

Table IV, Examples 18 to 30, show organic, polycationic polymers, which generally from

bo alternating ethylene and amine groups.

The characteristic feature of the polymers is the structure -CH ₂ -CH ₂ -N. However, there are several changes to the nitrogen atom and they can occur in the same polymer molecule, that is:

-CH ₂ -CH ₂ -NH

37
-CH ₂ -CH ₂ -N-CH ₂ -CH ₂ -

H
-CH ₂ -CH ₂ -N-CH ₂ -CH ₂ -

CH ₂ -CH ₂ -
and

-CH ₂ -CH ₂

-CH ₂ -CH ₂ -N ⁺ -CH ₂ -CH;, - CH ₂ -CH ₂ -

It is believed that EDCA and PEI are the same polymer obtained by different synthesis but their behavior is different. For this purpose, a comparison of example 20 with Example 27 referenced. Similar molecular weights and concentrations give similar results up to the last flow rate phase (fresh water after 15% HCl). Obviously, PEl is replaced by HCl washed out.

From Examples 18, 19 and 20 it can be seen that it gives an optimal molecular weight, with Example 19 being a bit too high.

The pH difference between Examples 21 and 22 shows that EDCAM is a little better with one neutral pH. Since EDCAM is quaternized, the pH should keep the nitrogen atoms in this Do not change the polymer.

The remainder of the compound in Table IV has primary, secondary and tertiary amines and a minor one Percentage of quaternary amines. Adjusting the pH to 4 converts the primary to secondary and tertiary amines practically in the ammonium state (amine hydrochloride).

Examples 29 and 30 are preferred embodiments according to US Pat. No. 2,761,843 Example 30 is described in claims 6 and 11 of U.S. Patent 2,761,843 and can be found in the table in column 6 of that US patent. These two connections can clog the Do not prevent test cell sand and the clay pack with fresh water. It is believed that the Molecular weights of TEPA and TETA are too low and that cation exchange takes place quickly, if the standard saline solution is passed through. This removal of the amine oligomers enables swelling of the sound when fresh water is sent through.

The flow test study according to the invention seem to show the effects of formation of to resemble geological formation more than the washout techniques of US Pat. No. 2,761,843, Column 5, lines 25 to 74. In accordance with the invention, the technique employed attempts the conditions in one simulate actual borehole, d. H.:

Stage 1 - The saline calibration simulates the flow of formation fluid;

Stage 2 - treatment with a clay treatment agent or sound control means simulates the treatment of the borehole;

Stage 3 - the flow with saline solution simulates the return of the borehole to the product

ίο

Level 4
Level 5

Level 6 -

tion. This stage; serves to check whether the fbrmation salt solution removes the clay treatment agent Monomeric clay treatment agents such as potassium, ammonium or calcium ions are removed in this stage;
the flow of fresh water simulates the introduction of extraneous water into the formation;

the 15% HCI flow simulates acidification treatment of the formation. If it is advantageous later when operating the borehole to clean it or to bring the borehole to a better production with acid, it is an advantage if one versus removal clay treatment agent resistant to cation exchange with hydrogen ions is present;

the flow with fresh water simulates the introduction of extraneous water into the formation. This is used to check the resistance of the clay treatment agent versus acid.

The method of operation according to US Pat. No. 2,761,843 is more for a water or backwater clarification and wastewater treatment where numerous polycationic compounds are used for treating oil or water wells.

Table V, Examples 31 to 41, contains examples of organic, polycationic polymers, which in their constitution differ from those of Tables II, III and IV are different. Examples 31 and 39 have ion saturation in the carbon bond. Examples 32 to 38 have a hydroxyl group on the carbon bond.

Except for Examples 40 and 41, they are effective clay treatment agents and tone control agents, respectively. Examples 33, 34 and 38 show the concentration effects, with Example 38 not has a particularly advantageous concentration.

Table VI, Examples 42 through 44 contains inorganic clay treatment agents and clay control agents, respectively. Examples 43 and 44 relate to inorganic, polycationic polymers according to the prior art.

Example 42 serves a dual purpose. It is the comparative example for Examples 43 and 44, and furthermore it is also an example for the removal of a monomeric, cationic clay treatment agent with a saline solution.

Examples 43 and 44 show that the inorganic, polycationic polymers towards acid are not stable, so that with a desired acidification of a borehole under certain circumstances a year after treatment with an inorganic clay treatment agent it would be advisable to put the clay in the Treat the borehole again after the acidification treatment.

Table VII, Examples 45 to 47, provides examples of how an organic, polycationic polymer as Clay treatment agents can act in a carbonate formation. The inorganic means like Hydroxyaluminum compounds (HOAl) are used for nine containing more than 5% carbonate material Formation not recommended because the acid salt (low pH value) reacts with the carboviate Hydroxyaluminum chloride into the ineffective aluminum

would convert nium hydroxide. Furthermore, aluminum hydroxide still has its own option as clogging precipitate to act in the capillaries of the formation. The metal salts according to US Pat. No. 3,382,924 are also acidic in terms of pH and tend to to be incompatible with carbon components of a formation.

Example 45 shows that a formation containing carbonate and clay in terms of capacity for ι ο Fluid production can be negatively affected or damaged. On the other hand, Example 46 shows that a organic, polycationic polymer a loss of permeability or permeability in a clay-containing and prevent carbonate formation. r> The increase in permeability after acid treatment in Example 46 is likely attributable to the removal of carbonate by the acid.

Since the marble pieces had a pointed shape, they give a lower permeability than the sand, which they replaced, although the particles of both materials have the same conical size. That Example 47 evidently shows a low flow rate on calibration due to this influence. In example 47 shows an organic, polycationic polymer,;> ■ -> that it is capable of the loss of permeability as a result of swelling and / or migration of to prevent trapped fine particles and clay in the formation even if carbonate is the main component of the formation. ji>

Table VIII, Examples 48 to 52 show that polycationic polymers prevent formation with oil do not wet.

Since cationic surfactants can treat clays and keep clays and fine particles of S5 from swelling and / or migration, but have the disadvantage that they cause oil wetting of the formation, it appears advisable to use the organic polycationic polymers with regard to their ability to investigate the wetting of a 4 <i ^:: ormation by oil or a wetting by water. Certain examples have additional flow rate phases added in the remainder of the procedure, namely with hydrocarbon, fresh water and hydrocarbon. Diesel oil was used as a suitable hydrocarbon. Examples 48 to 51 show a pattern of high diesel oil flow and e ^; low water current. This is a good sign of water wetting. Example 52 shows a "neutral" state => which neither a special oiler yet o a Wasserbenetzun "takes place.

The advantages which emerge from Examples 48 to 52 are that diesel oil has a viscosity of about 2 times that of fresh water and still has a high diesel oil flow rate was obtained. When there are two phases or fluids in the same capillary flow system, a condition still exists here which is called »relative Permeability «, whereby none of the flow rates is as high as if only one Phase or a single fluid would be present. It is actually the sum of the relative permeability for oil and the relative permeability for water when both oil and water are present in it Pore spaces seldom equal the permeability of the formation in which there is only one fluid. In almost all of them Cases, the sums are worth less.

For practical reasons, these flow rates are rates after the flow of the previous one Fluids had stopped. This does not mean that the other fluid was completely washed out by the flow became. On the contrary, an equilibrium is reached, resulting in a saturation that can no longer be canceled will be produced. The non-flowing fluid is still there, even if it is no longer mobile is. The wetting fluid usually adheres to the capillary walls while the non-wetting fluid usually present as spheres that are trapped in pore enlargements.

Examples 49 to 51 not only show that the generally undesirable oil wetting by the organic, polycationic polymer unlikely but that it is also the ratio of water to oil as it is drawn out of the formation, can improve. This is another particular benefit.

Table VIII A, Examples 52A through 52B are Examples of polymers which contain ester and ether bonds. These contain condensates Tall oil or tall oil condensates. They give good protection for clays and show good resistance to them an acid wash.

There has been concern about tall oil's long carbon chains, which cause oil wetting could cause. However, Examples 52A and 52B show water wetting and Example 52B shows a "neutral" wetting.

Table IX, Examples 53 to 61 show tests for clay stabilization on Berea kernels.

The Berea Formation is encountered in the state of Ohio, United States, and the neighborhood. It is often used as a standard used for scientific and / or technical investigations in the field of the petroleum industry. Natural formations often vary within very short distances. The differences are in a block a formation of 15 χ 20 χ 15 cm noticeably. Some Berea sections do not contain enough clay to to be sensitive to water. The sections selected for investigation were prior to use investigated whether there was any reasonable assurance that they would be constipated by fresh water were sensitive. Example 53 shows that the cores from this block of Berea sandstone were sensitive to a flow of fresh water. The example 54 is also a Comparison test. In example 54, acid is used after the calibration, although only about 2.8% strength Acid solubility was present, it must be an important one. May have occurred in the capillaries since the The flow rate after the acid treatment was doubled. As can be seen from the note (footnote) a), saline solution was used to confirm the results of the acidification treatment. The following Fresh water flow phase shows that despite the considerable opening of the core by the acid, the Clay components were still present in a state that they considerably increased the permeability Dimensions could negatively affect.

Examples 55 to 58 show that the carbonate content In the core, the injection of inorganic, cationic polymer interferes, if not acid as Solvent is used. If the carbonate content was greater than £ 2%, i.e. H. on the order of 10%, the acid solvent would not be enough.

Example 59 shows that hydroxyaluminum hemverbin-

fertilize these particular kernels can handle. The acid solubility of 2.8% is within expected Tolerance of 5% for hydroxy aluminum compounds. The use of an acidic carrier fluid would the hydroxyaluminum compound before injecting into -> change the core.

Examples 60 and 61 show that the pH is no Factor in the treatment of clays with an organic, polycationic polymer. It result in good initial flow rates for fresh ι ο water without resorting to acidic carrier fluids had to be taken.

Table X, Examples 62 to 68 show a treatment to remedy the foregoing negative impairment of the permeability of ι, Berea cores.

It is believed that the prevention of loss of permeability caused by swelling and / or Wandering caused by clays or other fine particles is the best method of securing a continuous production of a well is. However, it is often necessary to do so beforehand treat damaged formations.

Examples 62, 63 and 64 are comparative tests which show that the cores can be removed from 2-5 by fresh water can be damaged or negatively influenced that a treatment with saline solution is ineffective, and finally, that HCl is a considerable aid in reopening the core, but that the Core permeability is not permanently protected. jo

A comparison of Examples 63, 65 and 66 shows that organic, polycationic polymers are a Have pronounced good treatment to repair the damage. A comparison of Examples 64, 67 and 68 gives.

that acid alone gives a good initial opening of the nucleus, but that organic, polycationic Polymer gives better long-term results.

Table XI, Examples 71 to 74 show the use of alcoholic or organic, polar solvents other than water than normal liquids to replace Hydrocarbons.

In formations which do not produce sand as long as only hydrocarbons are produced, however, from their own formation give off water when the water level rises and the water production begins, aqueous preparations of organic, polycationic polymers can disintegrate or prevent destruction without the aqueous preparation itself causing this destruction, however some well operators fear introducing any watery ones Fluids in general, even those fluids that are used to prevent the destruction or disintegration of the Formation are designed by water wetting. In addition, it is possible to be extremely water-sensitive Formations exist. So, therefore, to avoid the fears and even the possibility of one Avoiding softening of extremely water-sensitive formations can be an organic, polycationic Polymer in alcohol, ketone, monoethers of glycol or other non-aqueous solvents are dissolved, which have sufficient solubility for the polymers in question, and the The essentially non-aqueous solution of the polymers obtained can be used to treat the formation can be used.

Claims (1)

Patent claims: 1. A method for the treatment of clays containing formations against a swelling and a Dispersion of clays by the action of water, in which an organic, polycationic Carrier fluid containing polymerizate with a molecular weight of at least about 1000, in particular introduced into the formation with the addition of a salt and / or a mineral acid or is applied to the formation, characterized in that the organic, polycationic polymer at least one compound of the following formula is used: