MX2013008318A - High density polyanionic cellulose and use thereof as a suspension for drilling, finishing and repairing oil and gas wells. - Google Patents

Abstract

High density, non-ionic and liquid polyanionic cellulose, which is a product for facilitating the induction thereof in oil wells, this being a viscosity agent faster than conventional agents, the management thereof being more efficient, removing the product loses instead of using the powder version. The invention has a higher dispersion, in the different types of slurries used for the drilling, repair and finish of oil and gas wells. In addition, this product is environmentally friendly.

Description

HIGH DENSITY POLYANIONIC CELLULOSE AND ITS USE AS SUSPENSION FOR DRILLING, TERMINATION AND REPAIR OF WELLS PETROLEUM AND GAS DESCRIPTION OBJECT OF THE INVENTION The present invention relates to the composition, method of preparation and application of a fluid product, formulated with a mixture of high density polyanionic cellulose of nonionic cellulose ether highlighting the properties of high purity. Resistant to pressures and temperatures, which can be used for drilling, completion and repair of oil wells.

BACKGROUND The present invention relates to the composition, method of preparation and application of a fluid product, formulated with a mixture of high density polyanionic cellulose of nonionic cellulose ether highlighting the properties of high purity. Resistant to pressures and temperatures, which can be used for drilling, completion and repair of oil wells, and more specifically for drilling, finishing and repairing the production area of offshore, terrestrial and lacustrine wells, producers of hydrocarbons (oil crude, gas and oil-gas mixtures and condensates. The invention has the particularity of significantly reducing damage to the permeability of the water-soluble production formation to provide the density characteristics, polymers and special additives to provide the product with the physicochemical properties that all drilling fluid, completion and repair of wells requires to fulfill its functions, and above all to provide a thermal resistance of 85 ° C up to 150 ° C lubricating the production line. A primary feature of the present invention is the composition that integrates the drilling fluid / completion / repair of oil wells is to increase the viscosity and control losses by filtration that do not require long times, high cutting speeds or heating. Turning it into a producer highly friendly with the environment.

Specifically, the present invention relates to compositions containing liquid polymer for use as a thickening agent to make viscous brines and provide thick fluids. High density polyanionic cellulose, non-ionic cellulose ether, [C6H702 (OH) 2CH2COONa] n, is a thickener and suspending agent. As well as Fine grade mineral oil, Quaternary amine, Tall oil fatty acids and methanol.

For the drilling of an oil well it is necessary to use a fluid (traditionally known as mud) which can be water base, oil base or a gas in order to carry out multiple functions. This fluid must, among other things, counteract the pressures of the drilling fluids, cool and lubricate the auger, carry the perforated cuttings to the surface for their separation and be recycled, after conditioning, to reintroduce it to the well itself.

During the drilling operations, different formations (shales, sands, sandy shales, limestones, marls, shales, shales) are traversed before reaching the formation containing the hydrocarbons that have to be extracted for commercialization. Usually the deposits where the hydrocarbons are located consist of carbonated rocks, sands and / or sandy shales, which by virtue of their permeability can allow said hydrocarbons to flow naturally taking advantage of the existing pressures in the deposits or to be depressed deposits. which require the use of secondary recovery techniques (pneumatic pumping, mechanical pumping, electro-centrifugal pumping.). Invariably, the flow of hydrocarbons through the porous medium will very much depend on whether the insoluble particles of the traditional drilling fluids have invaded said areas, causing, among other causes, the clogging of the pores of the formation, and with this the reduction of hydrocarbon production. The permeability is the ease with which the pores of the formation can allow the free flow of a fluid through them, which will depend to a large extent on how much the pores are communicated with each other and that there are no foreign particles to the training that prevent or block the passage of fluids through he, to this process of invasion or blockage of the pores of the formation is traditionally known as damage to the production formation, which is caused by the fluids used during the drilling, completion or repair of oil wells.

The solids contained in traditional drilling fluids are generally insoluble solids in water and oil, which, when drilling, invade the production formation, causing the formation pores to clog and thus reducing their permeability. The chemical nature of these solids (usually densifying agents such as barite, ilmenite, galena, iron oxide) prevents them from being dissolved by the traditional 15% HCI treatment, causing irreversible damage to the permeability of the formation.

To solve the problems of damage to the production formation have been using fluids formulated based on heavy brines free of solids, which present the advantage that do not require insoluble solids (such as barite, calcium carbonate, iron oxide, galena .) to increase the density that the high pressure high temperature wells require to control formation pressures, this type of fluid increases its density by dissolving salts or salt mixtures (NaCl, KCI, CaCl2, CaBr2, ZnBr2l NaHC03, NaBr , KHCO3, NaHCO3, NH4CI, among others) in water, in such a way that there are no insoluble solids (in suspension) that could, during the perforation of; area producer, invade the formation with the consequent plugging and reduction of the permeability and well production.

Polyanionic cellulose high density dust presents various problems when pouring into oil wells, which requires mixing properly with another additive that allows its maneuverability, adding the preparation time it takes to be used even in many cases arrive to fish lumps or eyes which hinders or impedes the specific function of providing a higher viscosity of the brines.

They can be taken as references of existing patents in the market in synthetic and water-based liquid versions such as: Patent US 8338340 provides a drilling fluid comprising: a nonionic surfactant including at least one of a branched alcohol ethoxylate and an alcohol ethoxylate with a lid, a detergent builder and a viscosity agent.

A drilling fluid according to the present invention may also include, if desired, a lubricant, also called a secondary surfactant. The lubricant can act to soften the tar and provide a lubricating action to assist the drilling liners and operate in long horizontal sections of a well. The lubricant can be non-ionic. High-flash point and vegetable oils, such as those with a flash point greater than 148 ° C, may be of some use in! the present drilling fluids. Useful lubricants may include, for example, methyl esters of fatty acids, for example, with a lipophilic Hydrophilic (HLB) of about 6, as are commonly available as soybean oil, for example, commercially available as SoyClear ™ products by AG Environmental Products , LLC or Oleocal ™ products by Lambent Technologies Corp., or canola oil. The lubricants can be added to the drilling fluid when the liquid is prepared, directly in the tanks and can alternatively or in addition by addition by first application to metal surfaces, such as screens, etc. on the surface to enter this mode the drilling fluid stream.

In one embodiment, a water-based drilling fluid can be prepared as set forth above, including 0.5-1.5% by weight secondary surfactant, such as, for example, 0.5-1.5. % by weight of a methyl ester of soybean oil.

Liquid loss reducers can also be used in a drilling fluid according to the present invention if desired. Some common fluid loss reducers include, for example, starches, PAC (High Density Polyanionic Cellulose) and / or CMC (carboxymethyl cellulose). Some of these chemicals can also have a viscosity function. The loss of reduced fluid can provide steric stabilization of the nonionic surfactants.

The patent 8071509, the present invention refers to drilling fluids based on glycerol. In particular, the invention relates to drilling fluids comprising a volume of 95 to 20% glycerol / water solution capable of stabilizing water-sensitive formations during drilling and the use of this type of solutions for drilling a well that They have water sensitive formations.

Glycerol / water solutions were tested for their ability to inhibit the hydration of water-sensitive minerals, such as sodium montmorillonite and sodium bentonite with and without several additives selected from: partially hydrolyzed polyacrylamide (PH-PA), hydrolyzed partially polyacrylonitrile (PAN-PH); (c) metal halides such as CaCl 2, and Group 1 metal salts such as KCI.

In addition, other known additives can be incorporated to impart known properties such as viscosity, yield point, etc. as is known to those skilled in the art. These additives may include: xanthan gum, high density polyanionic cellulose, carboxymethyl cellulose, water dispersible polymers, alcohol ethoxylates, d-Limonene, terpins and fatty acids.

Tests showed that water-sensitive clays, such as sodium montmorillonite and sodium bentonite, did not hydrate when they were introduced into a glycerol solution containing greater than 20% (by volume). of glycerol. In addition, solutions containing 1% (wt%) halides of dissolved metals (such as KCI) showed that the metal halides could be dissolved in an aqueous phase emulsified by glycerol.

In addition, the tests also demonstrated that the viscosifying polymers including polyacrylamide and xanthan gum added to the glycerol solutions were dissolved and produced desired viscosifying properties.

DETAILED DESCRIPTION OF THE INVENTION High density polyanionic cellulose is a derivative is a type of nonionic cellulose ether highlighting high purity properties. Which provides rheology, bacterial resistance, works in any type of salinity, does not contain biocides, avoiding developing high gels in its formulation.

Polyanionic Cellulose high density, is a cellulosic and ethylene polymer, which forms a viscous gel soluble in water and in ethanol, can be used in substitution Cellulose Hydroxyethyl or CMC, fulfilling a similar function to this, giving results of resistance to temperatures of 85 ° C to 150 ° C.

Mineral oil is a liquid by-product of the distillation of petroleum from crude oil. A mineral oil in this sense is an oil colorless transparent typically composed of alkanes (typically 15 to 40 carbons) 1 and cyclic paraffin. It has a density of about 0.8 g / cm3. 2.

The quaternary amine is a positively charged polyatomic ion, of structure NR4 +, R starting from an alkyl group or an aryl group. Unlike the ammonium ion (NH4 +) and the primary, secondary or ternary ammonium cations, the quaternary ammonium cations are permanently charged, regardless of the pH of their solution. Salts of quaternary ammonium cations linked to an anion.

Fatty acids derived from the Tall 0/7, is a yellowish liquid, characteristic Odor, obtained as a by-product in the manufacture of paper pulp, from coniferous, by the Kraft process, also called liquid resin, is obtained from the residual black liquor from the manufacture of cellulose pulp by alkaline processes and, more especially, by the sulphate process. It is a liquid consisting essentially of a mixture of fatty acids and resin acids.

Methanol, also known as methyl alcohol or wood alcohol. At room temperature it appears as a light liquid (low density), colorless, flammable and toxic that is used as a solvent, its chemical formula is CH40.

In order to obtain the non-ionic high density polyanionic cellulose object of the present invention, it is necessary that its elements have the following degree of concentration: Polyanionic cellulose high density of 80% to 99%, preferably 99%; fatty acids derived from tall oil from 80% to 99%, preferably 99%, fine grade mineral oil from 80% to 100%, preferably 100%; Methanol 70% to 100%, preferably 100%; Quaternary amine from 80% to 99%, preferably 99%.

The present invention has a viscosity of 5,150 - 27,000 cps, pH 8.0 1 1, 0, maximum humidity 8, nacmc% (purity) minimum 60, substitution of degree 0.70 to 0.90.

EXAMPLE 1. Preferred obtaining method of the present invention: They are introduced: 99% fine grade mineral oil + fatty acids derived from 99% Tall Oil + 100% methanol + 99% Quaternary amine, in a mixer; once said components are introduced, said mixer is turned on and stirring is started at 1000 rpm, until the integration of the components a viscous texture is observed, then the Polyanionic Cellulose with high density in powder, preferably at 99%, is added. the mixer by agitation is increased to 2000 rpm, to ensure that no fish eye or eye is left, and stirring is maintained, to obtain the high density nonionic Polyanionic Cellulose, which is a suspension, viscous in cream color, stable and manageable at room temperature to finally obtain the nonionic hydroxyethyl cellulose object of the present invention.

Polyanionic cellulose high density nonionic will not experience the dehomogenization of the elements when it is at rest or storage, due to the system of mixing by agitation, which in other liquid products, happens the separation of the elements when at rest. Making a unique suspension, eliminating the sedimentation of the pure polymeric solids Polyanionic Cellulose high density, converting it into a fully pourable compound. This allows an efficient handling to make quick mixes and sweeps without the need of mixer equipment, to pour it into the oil well.

EXAMPLE 2. Preparation of 1 liter of hydroxyethyl cellulose The amount of the components that are used to prepare 1 liter of the present invention are detailed in table 1.

Table 1. Amount of elements used in the 1 liter preparation of the present invention.

The present invention comprises 40% of High Density Polyanionic Cellulose which together with the rest of the elements that make up the formula provide a liquid state for brines in high density, making it not degrade by common bacteria. Providing a pseudoplastic rheology not allowing to develop high gels. Making a product easy to handle, increasing the volume of the fluids facilitating their extraction, working in any type of salinity and does not require biosides.

EXAMPLE 3. Method of Application of the invention The fluids that are used in the drilling of a well are administered by the so-called circulation system and injection treatment. The system is composed of intercommunicated tanks that contain mechanisms such as: sieves / s: mechanical device, first in the drilling fluid cleaning line, which is used to separate trepan cuttings or other solids found in the same in his return from the well. The fluid passes to through one or several vibrating strainers of different meshes or size of holes that separate the larger solids; the degasser / is; Desander / developer The fluid is pumped tangentially through the interior of one or more cyclones, cones, within which the rotation of the fluid provides sufficient centrifugal force to separthe dense particles by effect of their weight. The mixing funnel or hopper that is used to add dusty additives or suspensions to the drilling fluid and the centrifugal pumps and piston pumps (2 or 3): they are responsible for receiving the injection prepared or reconditioned from the tanks and push it inside from the drilling column through the passage or passages of the trephine and return it to the surface by the resulting annular space between the drill string and the wall of the well, loaded with the cuttings of the trepan, and contamin by the components of the traversed formations . The drilling fluids; Its design and composition are established according to the physico-chemical characteristics of the different layers to be traversed. The qualities of the selected fluid depends on the density, viscosity, pH, filtering, chemical composition, they must contribute to fulfill the different functions of the same, such as cooling and cleaning the trepan; carry the cuts that generate the action of the trepan, care of the environment.

EXAMPLE 4. Evaluation of the viscosity of Polyanionic Cellulose high density nonionic Table 2 shows the results obtained by the viscosity tests to which it was subjected by the Brookfieid method, polyanionic cellulose of high density nonionic.

Table 3. It shows the tests made of corrosivity, reactivity, explosivity, toxicity, inflammability, biological infectious.

The data shown in the various tests done, the results are shown: absent, negative and in some cases does not apply.

Claims (21)

CLAIMS Having described my invention enough, I consider it as a novelty and therefore claim as my exclusive property, what is contained in the following clauses:

1 . Non-ionic high density polyanionic cellulose characterized because it comprises high density polyanionic cellulose from 35% to 50% w / v ratio, from 50% to 99% purity; fatty acids derived from ra // o / Y from 1% to 8% v / v ratio, from 50% to 99% purity; Fine grade mineral oil from 40% to 60% v / v ratio, 50% to 99% pure; methanol from 1% to 5% v / v ratio, from 50% to 100% purity and quaternary amine from 1% to 8% v / v ratio, from 50% to 99% purity.

2. Nonionic high density polyanionic cellulose, according to claim 1, characterized in that it preferably comprises high density polyanionic cellulose at 40% ratio w / v at 99% purity; fatty acids derived from ra // oil at 2% v / v ratio, at 99% purity; Fine grade mineral oil 53% v / v ratio, 99% pure; methanol of 1% v / v ratio, at 100% purity; quaternary amine 4% ratio v / v to 99% purity.

3. Polyanionic high density nonionic cellulose, according to claim 2, characterized in that it comprises high density polyanionic cellulose in 53% w / v ratio.

4. Polyanionic high density nonionic cellulose, according to claim 3, characterized in that it comprises high density polyanionic cellulose in 99% purity.

5. Polyanionic high density nonionic cellulose, according to claim 2, characterized in that it comprises fatty acids derived from tall oil in 2% v / v ratio.

6. Nonionic high density polyanionic cellulose, according to claim 5, characterized in that it comprises fatty acids derived from tall oil in 99% purity.

7. Polyanionic high density nonionic cellulose, according to claim 2, characterized in that it comprises fine grade mineral oil in 53% v / v ratio.

8. Polyanionic high density nonionic cellulose, according to claim 7, characterized in that it comprises 99% pure fine grade mineral oil.

9. Polyanionic high density nonionic cellulose, according to claim 2, characterized in that it comprises methanol in 1% v / v ratio.

10. Polyanionic high density non-ionic cellulose, according to claim 9, characterized in that it comprises 100% pure Methanol.

1 1. Nonionic high density polyanionic cellulose, according to claim 1, characterized in that it comprises Quaternary Amine in 4% v / v ratio.

12. Polyanionic high density nonionic cellulose, according to the claim, characterized in that it comprises 99% pure Quaternary Amine.

13. Polyanionic high density nonionic cellulose, according to claim 1, characterized in that its viscosity is 5,150-27,000 Cps.

14. Polyanionic cellulose high density nonionic, according to claim 1, characterized in that the results of its corrosivity test, is within the normal range.

15. Polyanionic high density nonionic cellulose, according to claim 1, characterized in that the results of its reactivity test, is within the normal range.

16. Polyanionic high density nonionic cellulose, according to claim 1, characterized in that the results of its explosion test, is within the normal range.

17. Polyanionic cellulose high density nonionic, according to claim 1, characterized in that the results of its toxicity test, is within the normal range.

18. Polyanionic cellulose high density nonionic, according to claim 1, characterized in that the results of its flammability test, is within the normal range.

19. Polyanionic cellulose high density nonionic, according to claim 1, characterized in that the results of its infectious biological test, is within the normal range.

20. Polyanionic cellulose high density nonionic, according to claims 1 to 19, characterized in that it is obtained by the introduction of fine grade mineral oil, fatty acids derived from Tall OH, methanol, quaternary amine, in a mixer; once said components are introduced, said mixer is ignited and stirring starts at 1000 rpm. , until the integration of the components a viscous texture is observed, then the Polyanionic Cellulose with high density powder is added, in addition the stirring mixer is increased to 2000 r.p.m. , to ensure that no lump or fish eye remains, and agitation is maintained, to obtain the nonionic high density polyanionic cellulose, which is a suspension, viscous in cream color, stable and manageable at room temperature to finally obtain the Polyanionic cellulose high density nonionic. twenty-one . Use of the nonionic high density polyanionic cellulose according to claims 1 to 19 as a suspension for the drilling, completion and repair of oil and gas wells.