MX2010014301A - Oil well fractuirng fluid. - Google Patents

Abstract

The present invention refers to a fracturing fluid based on hydrocarbons with an aromatic content higher than 40% by weight and paraffinic hydrocarbons and additives for regulating visccosity; said fluid has densities of from about 0.89 and 0.96, and along with the additives improves the viscosity index higher than 95.

Description

FLUID OF FRACTURATION OF PETROLEUM WELLS.

FIELD OF LAW.

The present invention relates to the field of oil well drilling, more specifically to a fluid used for the fracturing of oil wells pumped from the bottom thereof, whose main components are hydrocarbons with aromatic contents and paraffinic origin mainly .

Aro s? and???? ed DE? _? ReveSO, In the state of the art, fracturing fluids are used that are injected into one or more wells drilled in order to create one or more fractures within the walls of the same well to help the oil flow in the reservoir, ie, they are used to minimize and assist in the control of fluid loss due to the existing pressures in the underground formations. Generally fracture fluids have suspended propellant particles that are located in the fractures to prevent them from closing once the excess pressure of the oil has decreased, thus forming conduction channels within the formations so that Hydrocarbons can fiuir.

¿ Jan! state of the art additives are used for e! fracturing that contain solid spherical particles of different diameters; but it causes the fractures to sometimes be obstructed by the accumulation of solids.

The Mexican patent application MX 2010006453, published e! October 5, 2010, whose inventor is Crandali Michaeí D. and collaborators, describes a fracturing fluid based on solid epoxy particles, and an epoxy resin as a curing agent and some type of proppant particles, is that it adheres to resin and the epoxy particles to the proppant grains to allow the flow of the hydrocarbon and avoid the closure of the fracture.

U.S. Patent No. 7,427,583, issued September 23, 2008, to Schlumberger Technology Corporation and whose inventor is Isabeile Couiiiet et al., Describes and protects a viscoeiásic aqueous fracturing fluid for use in the recovery of hydrocarbons, Composed primarily of a viscoeiásic surfactant and a hydrophobically modified polymer, the advantageous concentration of the polymer hydrophobically modified to exceed certain levels of concentrations and result in a gel structure with a viscoeiσsic surface active agent concentration below ia. Typical concentration used for the pure viscoeiásic surfactant agent, said fluid is injected into the rock formations to fracture said formations and allow oil flow.

U.S. Patent No. 7,399,732, issued on July 15, 2008, to Caifrac Weii Sen / ices, Ltd., whose inventor is Travis L. Aíian et al., Describes and protects a fracturing fluid and improved method for Hydraulic fracturing of a formation, the fluid includes a tensio-active agent, an organic sai of dispersion or water-soluble ammonia, an acid and a low molecular weight organic solvent. Fracturing fluids generally contain polymers based on high molecular weight polysaccharides, as agents that convert into gels; The current method is based on the chemistry of the tensioactive agent which does not alter the current chemical composition of the fluid, the key of the invention is the use of a surfactant amphoteric giicinate surfactant in acid conditions exhibiting cationic properties.

United States of America patent 7, 096, 947, granted on August 29, 2006, for Halliburton Energy Services, inc. whose inventor is Bradiey L. Todd et al., describes and protects a fracture fluid that includes an additive for the control of fluid loss, and the method of using said fluid in underground formations; The fluid mainly contains a viscosity condenser and additives for the loss of fluids coníroi that include a maíeriai that deforms and degrades, that is, that does not re-chilling or reconsoiida inside the well.

United States of America Patents No. 6,929,069 and 6,729,408, issued on August 16, 2005 and May 4, 2004, respectively, for Schlumberger Technology Corporation, whose inventor is composed mainly of oxides ds amines that help in the removal of fluid from the invaded areas.

U.S. Patent No. 6,838,418, issued on January 4, 2005, to Caifrac Well Services, Ltd., whose inventor is Travis L. Alian et al., Describes and protects a fractional fluid including a polar base with a poii-acriiaio of half molecular weight (0.1.5.0%) and an activator to ionize the poii-acriiaio to a lroscopic state. As a main characteristic of the fractionating fluids is the variable viscosity, that is, fluids that constantly require the addition of additives that selectively alter the viscosity. The preferred embodiment of this invention is an emuified fluid that uses carbon dioxide as an internal phase and a medium molecular weight poi-acrylate as an external phase resulting in a gei that can easily be broken by adding NaCl and KCl salts.

U.S. Patent No. 5,591,700, issued June 7, S97, to Halliburton Company, whose Inventor is Phiilip C. Harris et al., Describes and protects an aqueous fractionating fluid containing a viscosity inhibitor containing an insensitive agent and an inhibitor that is solid under environmental conditions and dissolves as the temperature in the formation increases. The viscosity inhibitor of the invention is encapsidated by a water-soluble surfactant agent that promotes the dispersion of the polymeric fragments of gei in the fractionating fluid.

D BRIEF DESCRIPTION OF THE INVENTION It is an object of the present invention to provide a fracturing fluid that operates at pressures of up to 8000 ib / in2 (562.96 Kg / cm2) and at a temperature of up to 100 ° C.

It is another object of the present invention to provide a fracturing fluid that is easily pumped.

It is also an object of the present invention to provide a fracturing fluid that is compatible with ios, additives that are added in the process of fracturing itself.

It is yet another object of the present invention to provide a fracturing fluid which suitably carries the proppant which is used to prevent the fracture from closing.

It is still an object of the present invention to provide a fracturing fluid that does not allow the subsoil clays to swell and thereby prevent blockage of the well.

It is also an object of the present invention to provide a fracturing fluid having an adequate solvency index which allows the fluidity of the hydrocarbon to be incorporated into production within a period of 4 and up to 12 hours maximum.

It is another object of the present invention to provide a fracturing fluid with adequate solvency and stability parameters.

It is another object of the present invention to provide a fracturing fluid with additional additives of such form that the reoiogy is strengthened in an appropriate manner at the operating temperatures and pressures during the fracture of the well.

DETAILED DESCRIPTION OF THE INVENTION.

Crude oil and natural gas reside in natural porous formations on which wells are drilled to facilitate extraction. Oil and natural gas flow through the well. Driven by a pressure gradient that exists between the formation and the walls of the well; Typically, surface pumps are required to help the oil flow to the surface.

Most of the wells are hydraulically fractured to increase the flow, then the fracturing fluid is pumped down into the well and specifically into the formation at a very high pressure and velocity sufficient to carry a fluid mass of solid particles called "proppant" within the fracturing fluids and are carried by them within the formation through the fractures to keep them open and allow the flow of the fracturing fluids and the oil that they drag when washing the pores of the fracture. training.

One consideration for selecting the fractional fiuid is the ability to manipulate parameters such as pressure inside the well, the capacity to transport and deposit large volumes of proppant within the fractures in the formation, the power to reflow without leaving residues in the walls. of said fractures and the reoiological property that allows the fluid re-composition in the surface to be reused.

The term fracturing fluids refers to fluids that are used for injection at high pressures within the gas or oil wells (peiróieo), to fracture the geological formations that surround the well and thus increase its porosity. This allows the most efficient flow of hydrocarbons and increases the productivity of the well. Fracking has two objectives: Transmit energy to the bottom of the well so that hydraulically a fracture is generated in the rock where the oil is; Transport a proppant agent (usually sand) from the surface to the oil source to ensure its conductivity, generated by the fracture. This process involves the injection of an external fluid into the porous walls of the fracture.

The temperature of the well increases with depth and then the viscosity of the fracture fluid decreases, so that the fracture fluid must be reformed in order to maintain its execution properties. plurality of additives to maintain the necessary viscosity and adequate to the physical properties of! fluid.

Another drawback is that when the fracturing operation is completed, the pressure of the fracturing fluid decreases and returns to the well, which is necessary to allow the flow of hydrocarbons and increase the production of them.

The fracturing fluid of the present invention maintains the efficient production parameters according to international standards, since it maintains its properties of viscosity, temperature, specific gravity, it is also adapted to be used under pressure conditions of 2000Lb / in2 and up to 8000 Lb / in2 or e! equivalent of 140 g cm2 and up to 562.96 Kg / cm2, e! The fracturing fluid of the present invention consists of the following substances: ID Component one: hydrocarbon with aromatic content greater than 40% by weight.

Component two: hydrocarbon of paraffinic origin. 0 Component three: additive that improves the viscosity performance.

Atmospheric distillation characteristics of the fracture fiuid product.

Y Specific weight in a range of: 0.89 to 0.96 Content of total aromatics with a lower or equal proportion to 40% viscosity index greater than: 95 Sulfur content, with a maximum of: 4.5 Data sheet and methods ASTM with which the tests are measured The components of! The final product will be added in different proportions according to its origin and composition in order to obtain the specific parameters. The composition of the fluid is compatible with the additives that are added in the fracturing process to facilitate transport with the adequate performance in terms of fluidity, the proppant used to prevent the fracture from closing, presenting the property of not inflating the clays. disueitas coming from! subsoil and in this way avoids the biochecking of the hole and fractures of the well; it has an adequate solvency power in such a way as to allow the fluidity of the hydrocarbon found and allows the well to be cleaned with the advantage that the production is incorporated in a period of four and up to twelve hours maximum.

Since the fracturing fluid is composed of hydrocarbons, this allows the production of crude oil to be incorporated almost immediately into production, unlike water-based fracturing fluids, since these require treating the water used.

The fracturing fluid of the present invention is adapted to operate at pressures of up to 8000 Lb / in2 or its equivalent of 562.96 Kg / cm2, in the temperature range of 0 ° C to 100 ° C.

The present invention provides a fracturing fluid operating in a pressure range of (2000, 8000) ib / in2 (140.74, 562.96) Kg / cm2 and at a temperature of up to 100 ° C, it is easily pumped, with compatibility Improved with respect to the additives that are added to improve the viscosity performance, to transport in an improved way the proppant of! Well immersed in the fluid, the clays of the subsoil do not swell in contact with the fluid and have an improved aromatic content.

Claims (4)

CLAIMS.

1. - A fracturing fluid of oil wells consisting of a mixture of hydrocarbons, such as: a content by weight less than 40% of aromatic hydrocarbons, hydrocarbons of paraffinic origin; additive that improves the viscosity index of such form that assures the good performance of the fluid during the fracture obtaining a minimum viscosity index of 95; Inflammation temperature of 66 ° C minimum.

2. - The fracturing fluid of oil wells, according to claim 1, further characterized in that the content of total aromatics is less than 40%.

3. - The fracturing fluid of oil wells, according to claim 1, further characterized in that it allows the hydrocarbon to become fluid and the cleaning of the well begins.

4. - The fracturing fluid of oil wells, according to claim 1, further characterized because it is adapted to operate with pressures from 0 Lb / in2 to 8000 Lb / in2 or its equivalent 0 Kg / cm2 up to 582.96 Kg / cm2, in and! Temperature range from 0 ° C to 100 ° C.