System and Method of Treating a Subterranean Formation with Captured Exhaust Gases from Pump Engines and Auxiliary Equipment

Abstract

A system and method for capturing and repurposing exhaust gases from pump engines during subterranean formation treatments, such as hydraulic fracturing. The system comprises a source of a clean carrier fluid, gas injectors, a source of a treatment fluid, and a high-pressure pump, with configurable kits (e.g., Dry Kits, Wet Kits, Blender Dry Kits, Blender Wet, Single Pump Kits). Captured exhaust gases, including CO2 and N2, are combined with a treatment fluid to produce energized or foamed treatment fluids, improving viscosity and proppant transport. The system achieves up to 99.99% emission capture, supports foam qualities from 1% to 70%, and reduces environmental impact, equipment requirements, and operational footprint. Adaptable for onshore and offshore use, the invention enhances hydraulic fracturing efficiency and minimizes pollution.

Description

FIELD OF THE INVENTION

[0001] The present invention relates generally to hydraulic fracturing treatments. More specifically, the present invention provides a system and a method of treatment of rock formation with fluid composed of among other elements the exhaust gases captured from the fuel-powered equipment to reduce the environmental pollution, carbon footprint and modify the fluid parameters.BACKGROUND OF THE INVENTION

[0002] Hydraulic fracturing, is a widely employed method for enhancing the production rates and increasing the resource recovery from subterranean formations containing hydrocarbons, as well as other resources such as water, brine, and geothermal energy.

[0003] The hydraulic fracturing process involves the injection of pressurized fluids into rock formations to create fractures, which enhance the flow of resources to the wellbore. To maintain the conductivity of these fractures following the stimulation process, techniques such as the placement of proppants or the use of reactive fluids to etch the fracture walls are generally used.

[0004] While this method has been extensively optimized over time, several significant environmental and operational challenges remain unresolved.

[0005] One of the primary issues associated with hydraulic fracturing operations is the environmental impact of emissions resulting from the equipment used in the process.

[0006] Hydraulic fracturing operations rely on high-powered pumps and other fuel-driven equipment, which produce large volumes of exhaust gases, including greenhouse gases such as carbon dioxide and in the case of gas fueled equipment-methane, as well as other harmful pollutants. Methane emissions, which have a greenhouse potential significantly greater compared to carbon dioxide, pose major environmental concerns. Furthermore, the release of toxic air contaminants, such as nitrogen oxides (NOx), where x can take the value of 1.0 to 2.0, non-burned hydrocarbons, benzopyrenes, particulate matter (PM), and other types of pollutant, presents serious health risks to nearby communities and ecosystems. The cumulative emissions from hydraulic fracturing sites often exceed those from traditional extraction methods, further exacerbating environmental concerns.

[0007] Diversity of hydraulic fracturing operations creates the needs in different technologies and treatment fluids. Traditional formation treatment employs water-based fluids including, among others, foamed mixture. Foamed fluid is usually created via injection of a compressed nitrogen or carbon dioxide gases into a mixture of water, surfactants and other additives. Such gases are delivered to the operational site in a cryogenic form significantly complicating logistics, and reducing the profitability of the treatment.

[0008] The conditions described highlight the need for innovative methods and systems that effectively address the environmental challenges posed by hydraulic fracturing while improving operational efficiency.SUMMARY OF THE INVENTION

[0009] This summary is provided to introduce a selection of concepts in a simplified form, that are further described below in the Detailed Description. This summary is not intended to identify key features or essential features of the claimed subject matter. Nor is this summary intended to be used to limit the claimed subject matter's scope.

[0010] The present invention provides an integrated system for processing and utilizing exhaust gases in subterranean formation treatments, such as hydraulic fracturing operations. The system reduces environmental impact by capturing exhaust gases from engines and auxiliary equipment and incorporating them into the fluid preparation process, resulting in an energized treatment mixture suitable for high-pressure injection into the formation.

[0011] The system comprises a clean carrier fluid container configured to store clean carrier fluid for mixing with captured exhaust gases. Here and next within the scope of current invention unless stated separately under the definition of a “container” we assume any source of liquid fluid including but not limited to: drums, barrels, cisterns, tanks; manifolds-pipes, hoses and others. A gas injector, fluidly connected to both the clean carrier fluid container and an exhaust gas source, is designed to combine the clean carrier fluid with exhaust gases such as carbon dioxide (CO2) and nitrogen (N2) to form an energized mixture. The energized mixture is directed through an outlet pipeline to a treatment fluid manifold or a pipeline, where it is blended with a main treatment fluid, such as an aqueous-based fracturing fluid, to produce a fully prepared treatment mixture. A high-pressure pump, fluidly connected to the treatment fluid manifold or a pipeline, is configured to inject the prepared treatment mixture into a subterranean formation through a wellhead at pressures sufficient for fracturing the formation, often exceeding 10,000 psi.

[0012] The system may include additional features to enhance its capabilities, such as a manifold configured to gather exhaust gases from multiple sources before delivering them to the gas injectors, enabling centralized gas collection and processing. In some configurations, more than one gas injector is implemented to facilitate the mixing of carrier fluid and exhaust gases under reduced operating temperatures, optimizing system flexibility and performance. Additionally, one or more gas injectors may be positioned before the high-pressure pump to ensure effective mixing prior to pressurization. This invention effectively integrates exhaust gases into the hydraulic fracturing process, reducing emissions, minimizing waste, and enhancing the operational efficiency of fluid treatment.

[0013] The system of the present invention is versatile and can accommodate single or multiple injector configurations, allowing for a tailored approach to various formation treatment needs. Through these innovations, the present invention offers an environmentally conscious and efficient solution for enhanced subterranean resource extraction.BRIEF DESCRIPTION OF THE DRAWINGS

[0014] FIG. 1 is a flowchart illustrating the overall method of the present invention.

[0015] FIG. 2 is an illustration of one embodiment of the system of the present invention.

[0016] FIG. 3 is a diagram illustrating a first embodiment of the system of the present invention, wherein the system is shown with a single injection point for a Dry Kit.

[0017] FIG. 4 is a diagram illustrating a second embodiment of the system of the present invention, wherein the system is shown with multiple injection points for a Wet Kit.

[0018] FIG. 5 is a diagram illustrating a third embodiment of the system of the present invention, wherein the system is shown arranged for a Blender Dry Kit.

[0019] FIG. 6 is a diagram illustrating a fourth embodiment of the system of the present invention, wherein the system is shown with multiple injection points for a Blender Wet Kit.

[0020] FIG. 7 is a diagram illustrating a fifth embodiment of the system of the present invention, wherein the system is shown arranged for a Single Pump Kit.DETAIL DESCRIPTIONS OF THE INVENTION

[0021] All illustrations of the drawings are for the purpose of describing selected versions of the present invention and are not intended to limit the scope of the present invention.

[0022] As a preliminary matter, it will be readily understood by those skilled in the relevant art that the present disclosure has broad utility and applications. Any embodiment may incorporate one or multiple aspects of this disclosure and may include various features described herein. Furthermore, any embodiment identified as “preferred” is considered to represent the best mode envisioned for implementing the present invention. Other embodiments may also be discussed for illustrative purposes to provide a full and enabling disclosure.

[0023] Numerous adaptations, variations, modifications, and equivalent arrangements will be implicitly disclosed by the embodiments described and fall within the scope of the present invention. While the embodiments are detailed in relation to one or more examples, this disclosure is illustrative and not restrictive and is made solely to provide a comprehensive understanding of the invention. The detailed descriptions herein of one or more embodiments are not intended to limit the scope of patent protection that may be afforded, which scope will be defined by the claims and their equivalents. It is not the intention that the scope of patent protection be narrowed by interpreting any claim limitation not explicitly appearing in the claim itself.

[0024] For example, any sequences or temporal orders of steps in the processes or methods described are illustrative and not restrictive. Thus, although the steps of various processes may be presented in a specific order, they are not limited to a particular sequence unless otherwise indicated. Indeed, the steps can often be carried out in various sequences and orders while remaining within the scope of the present invention. The protection afforded is intended to be defined by the issued claims rather than the descriptions provided herein.

[0025] Additionally, it is important to note that each term used in this disclosure refers to what would be understood by a person of ordinary skill in the art, based on the context in which the term is used. Should the meaning of any term differ from a dictionary definition, the interpretation by a person skilled in the art will prevail.

[0026] Furthermore, as used herein, “a” and “an” generally denote “at least one” and do not exclude a plurality unless the context indicates otherwise. When used to connect a list of items, “or” signifies “at least one of the items” without excluding multiple items from the list. Conversely, “and” indicates “all items” within the list.

[0027] The following detailed description refers to the accompanying drawings, which use the same reference numbers throughout to refer to the same or similar elements. While numerous embodiments are described, modifications, adaptations, and alternative implementations are possible. Substitutions, additions, or changes may be made to the elements illustrated in the drawings, and the methods described can be varied by altering, reordering, or adding stages. Consequently, the detailed description does not limit the disclosure-rather, the proper scope of the disclosure is defined by the claims contained herein or those that may issue from it.

[0028] The present disclosure encompasses a range of aspects and features. Although many relate to methods, systems, and apparatuses within specific contexts-such as capturing exhaust gases for hydraulic fracturing techniques-embodiments of the present disclosure are not limited to this context alone. Other applications for the described methods and systems, including various industrial processes, may also be encompassed within the scope of this invention.

[0029] The present invention provides a method 100 and system 200 comprising a clean carrier fluid container 210, one or more gas injectors 320, a treatment fluid 250, a high-pressure pump 310, and various kit configurations, including Dry Kits, Wet Kits, Blender Wet Kits, and Blender Dry kits each designed to optimize the integration of captured exhaust gases into the treatment fluid based on specific operational requirements. Each component plays a critical role in capturing exhaust gases emitted from pump engines and auxiliary equipment during subterranean formation treatments, as illustrated in the provided figures (FIG. 1 through FIG. 7), which detail the operational flow and interaction of each component within the system.Method 100 of the Invention

[0030] The process of the present invention begins with the capture of exhaust gases produced by the machinery located at the wellsite, including, but not limited to, pump engines 310 and auxiliary equipment. These exhaust gases include carbon dioxide (CO2), nitrogen (N2), and other non-CO2 pollutants such as nitrogen oxides (NOx), non-burned hydrocarbons, and soot particles.

[0031] The process initiates at step 110 with the capture of exhaust gases. These gases are then introduced into the treatment fluid at step 120. By incorporating the exhaust gases, the treatment fluid 250 is energized or foamed, improving its efficiency during formation treatment at step 130. The incorporation of exhaust gases enhances fluid properties and reduces overall emissions, aligning with environmental sustainability efforts.

[0032] Once energized, the foamed treatment fluid 250 is injected into the subterranean formation, facilitating resource recovery or well enhancement by ensuring optimal distribution within the formation. The efficient use of gas helps create fractures within the formation, optimizing operational effectiveness and enhancing resource extraction. Effective fluid migration is critical, influencing the creation of fractures and the treatment of the formation.

[0033] The process may also include optional steps. The process may involve separating the different components of the exhaust gases at step 140. Additionally, the captured exhaust gases can be temporarily held in a pressurized vessel at step 150, providing controlled storage before further use. This step allows for selective utilization of the gases depending on their properties, optimizing the timing and delivery of gases into the treatment fluid 250, which is crucial for maximizing treatment efficacy.System 200 Components

[0034] Clean Carrier Fluid Container 210: This component serves as source of a clean carrier fluid 305 purposed to mixture with captured exhaust gases. The clean carrier fluid acts as a medium for transferring gases into the treatment fluid 310, connected to the gas injectors 320 through pipelines 220. The clean carrier fluid does not contain a proppant, natural sand, or reactive components, and is specifically chosen to enhance the efficiency of gas mixing and improve the overall effectiveness of the treatment fluid.

[0035] Gas Injectors 320: The system incorporates one or more gas injection points attributed as “injectors”320 that combine captured exhaust gases with the clean carrier fluid 305 before it enters the treatment fluid 250. Alternatively, gas injectors my combine the captured exhaust gases directly with the treatment 250 avoiding the intermediate mixture with the clean carrier fluid 305. The design of the gas injectors allows for precise control over gas flow rates and mixing ratios, ensuring optimal performance for various treatment fluids tailored to specific formations and operating conditions. Injectors include all mechanisms required to inject gases into a fluid.

[0036] Treatment Fluid 250: This fluid is injected into the subterranean formation and interacts with the energized clean carrier fluid (containing the captured gases) to enhance performance during formation treatment. The treatment fluid may include various additives to further optimize its properties for specific geological formations. Thus, treatment fluid containing synthetic proppant or naturel sand is called a slurry. Meanwhile, the treatment fluid including on chemically reactive capable of etch rocs usually does not contain solid additives like sand or proppant. Within the scope of current disclosure the treatment fluid 250 is called “slurry” unless defined separately.

[0037] Foamed fluid or foams requires certain ratio of liquid and gas phases to remain stable during the operation. The foam stability is usually supported via surfactants. In the case of a gas-fluid mixture is found in the outside of operational envelope for stable foams, such a gas-laden treatment fluids are called “energized fluids”. Thus, the main difference between stable foams and energized fluids is in the gas-to-fluid ratio. Within the scope of current disclosure these terms are used as synonyms.

[0038] High-Pressure Pump 310: This pump drives the combined mixture of energized fluid and treatment fluid 250 into the wellhead 400, providing the necessary pressure for effective injection into the formation. The pump is capable of maintaining high pressure throughout the injection process to ensure that the treatment fluid reaches targeted depths and efficiently interacts with the formation. High-pressure pumps usually contain an internal combustion engine capable of providing sufficient power to pressurize fluid and direct it to the wellhead 400 with a required flowrate. Such an internal combustion engine within the scope of current disclosure is called “engine”. The engine is connected via mechanical or electrical transmission with a hydraulic pump that pressurizes and pumps the treatment fluid here and next called a “pump”.

[0039] Auxiliary Equipment 315: This includes a wide range of auxiliary machines powered with an internal combustion engine usually employed during formation treatment operation. Such an equipment may include but not limited to low-pressure pumps, blenders, electrical generators, fans and many other types of equipment. Blender is a machine often used to prepare treatment fluid 250 or a slurry mixing water, chemical additives, proppant or sand depending on requirements for each particular formation treatment. Blenders prepare the slurry before it is directed into pumps therefore avoiding high-pressure environment during mixing.

[0040] This interconnected system enhances the hydraulic fracturing process by reducing emissions and improving the effectiveness of the treatment fluid 250. The adaptable nature of the system allows for optimization based on varying operational requirements, demonstrating versatility across different treatment applications.Kit Configurations

[0041] The present invention supports multiple configurations:

[0042] Dry Kit (FIG. 3): Collects exhaust gases in a common gas manifold before injection via a single injector 320 into the clean carrier fluid 305. Further, the mixture of clean fluid and exhaust gases is directed into a dedicated pump for pressurization. The obtained foam or an energized fluid is then mixed with the main high-pressure stream of slurry before the wellhead. This embodiment requires a single injector, an exhaust gases manifold, and a dedicated pump allowing for operational simplicity. Also, the use of dedicated pump allows for use of different types of pumps for pressurization of the main slurry and the gas-laden mixture providing additional control on the fluid parameters.

[0043] Wet Kit (FIG. 4): Utilizes multiple injection points 320, collecting exhaust gases as a mixture with a clean carrier fluid 305 at the gas-producing equipment. The obtained mixture is directed into a dedicated pump for pressurization before combining them with the main high-pressure stream of slurry. The embodiment eliminates the need in exhaust gas manifold, which is usually hot, by cooling down the gases with the clean carrier fluid. Also, the use of dedicated pump allows for different types of pumps for pressurization of the main slurry and the gas-laden mixture providing additional control on the fluid parameters.

[0044] Blender Kits (Blender Dry Kit FIG. 5, and Blender Wet Kit FIG. 6): Collect exhaust gases as described in the Dry and Wet Kits, with injection occurring at the slurry blender before the main pumps, eliminating the need in a dedicated pump. This optimizes the overall equipment layout of by combining the gases and treatment fluid at an early stage before pressurization.

[0045] Single Pump Kit (FIG. 7): Uses a single unit to generate and inject exhaust gases for producing energized or foamed slurry, simplifying the process and reducing equipment needs. In this embodiment exhaust gases produced by engine of a pump are injected into a fluid stream directed to the same pump. The cycle of gas generation, mixing them with the treatment fluid, and pressurization of the obtained foam or energized fluid happens within a single unit. Thus, the needs in additional gas manifolds and pipelines is eliminated significantly reducing the footprint of the assembly and simplifying the operation.

[0046] The figures (FIG. 3 through FIG. 7) illustrate the relationships and configurations of the various components, demonstrating the efficiency of the system in minimizing environmental pollution while optimizing subterranean formation treatments.

[0047] Although the invention has been explained in relation to its preferred embodiment, it is to be understood that many other possible modifications and variations can be made without departing from the spirit and scope of the invention.

Claims

1. A system for treating a subterranean formation with a treatment fluid mixed with exhaust gases from one or more internal combustion engines used to power pumps and auxiliary equipment, comprising:(a) a treatment fluid formulated for hydraulically fracturing an underground formation;(b) at least one source of the treatment fluid in the form of a blender or container, wherein the source is configured to supply the treatment fluid;(c) at least one internal combustion engine producing exhaust gases and configured to power a high-pressure pump;(d) at least one high-pressure pump connected to the internal combustion engine and capable of pressurizing the treatment fluid; wherein the high-pressure pump is fluidly connected to a wellhead and to the source of the treatment fluid;(e) at least one injector, fluidly connected to both the exhaust gas source and the conduit of the treatment fluid; wherein the injector is connected to a source of clean carrier fluid for mixing with the treatment fluid.

2. The system of claim 1, wherein the treatment fluid comprises a mixture of a water-based liquid and an artificial proppant or natural sand, thereby forming a slurry for hydraulic fracturing.

3. The system of claim 1, wherein the treatment fluid constitutes a liquid reactive medium capable of chemically modifying an underlying rock formation without the addition of an artificial proppant or natural sand.

4. The system of claim 1, wherein the internal combustion engines utilize different types of fuel to power the pumps and auxiliary equipment, including diesel, gasoline, fuel oil (mazut) crude oil, gas, or mixed fuel options.

5. The system of claims 1 and 4, wherein the internal combustion engines comprise piston, rotary, or turbine types, all configured to power pumps and auxiliary equipment.

6. The system of claim 5, wherein the temperature of the exhaust gases is monitored and controlled to enhance their performance in the treatment fluid.

7. The system of claims 1, 4, and 5, wherein various types of pumps provide sufficient pressure and flow rates for the treatment fluid.

8. The system of claim 7, wherein the pumps are configured to operate under varying pressures and flow rates according to the formation requirements.

9. The system of claim 1, wherein the captured exhaust gases are utilized to convert the treatment fluid into an energized or foamed form, thereby enhancing the fluid properties.

10. The system of claim 1, wherein exhaust gases are captured to reduce the carbon footprint of the treatment operation, capturing carbon dioxide in a range of 3.00% to 99.99% of the total CO2 exhaust produced during the operation.

11. The system of claim 1, wherein the exhaust gases are injected into the treatment fluid or clean carrier fluid without separating the gases into individual components.

12. The system of claim 1, wherein the exhaust gases are partially separated or purified before being injected into the treatment fluid or the clean carrier fluid.

13. The system of claim 1, wherein the exhaust gases are used directly as collected from the internal combustion engines without temporary storage in a pressurized vessel.

14. The system of claim 1, wherein the exhaust gases are temporarily held in a pressurized vessel before injection.

15. A method for treating a subterranean formation using the system of claim 1, comprising:(a) collecting exhaust gases in a common gas manifold;(b) injecting the collected exhaust gases into a clean carrier fluid via a single injector;(c) directing a resulting mixture from the single injector into a dedicated high-pressure pump for further pressurization; and(d) combining the resulting mixture with a main stream of pressurized treatment fluid directed into a wellhead for formation treatment.

16. The method of claim 15, wherein exhaust gases from each pump are collected and injected separately into the clean carrier fluid using multiple injectors and directed to a dedicated high-pressure pump for further pressurization, thereby combining the resulting mixture with the main stream of pressurized treatment fluid, which reduces the temperature of the hot exhaust gases and eliminates the need for a hot exhaust gas manifold.

17. The method of claim 15, wherein exhaust gases are collected in a common gas manifold before injecting into the main stream of treatment fluid via a single injector, with the gas-fluid mixture directed into the main high-pressure pumps for further pressurization and eliminating the need for a dedicated pump.

18. The method of claim 16, wherein exhaust gases from each pump are collected and injected separately into the clean carrier fluid using multiple injectors, and the gas-clean carrier fluid mixture is directed into the main stream of treatment fluid before going into the main high-pressure pumps for further pressurization, which eliminates the need for both a dedicated pump and a hot exhaust gas manifold.

19. The method of claim 16, wherein exhaust gases generated by a single internal combustion engine are collected and injected into a stream of treatment fluid directed to the fluid end of the same engine's high-pressure pump assembly for further pressurization into a wellhead, thus isolating the processes of gas generation, injection, and mixture pressurization within a single pump assembly.

20. The method of claim 15, further comprising monitoring the temperature of the exhaust gases during collection to optimize their use in the treatment fluid.

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