Method, apparatus, and device for determining hydrocarbon bubble point pressure

Abstract

This application discloses a method, apparatus, and device for determining the bubble point pressure of hydrocarbons. The method includes: acquiring preset experimental parameters, which at least include preset pressure and preset temperature, and are based on a target reservoir; performing phase transition simulation on a hydrocarbon sample in the target reservoir based on the preset experimental parameters, the phase transition simulation being implemented through a microfluidic device connected to a microfluidic chip corresponding to the target reservoir; acquiring phase state image data of the hydrocarbon sample under various pressure data; and determining the bubble point pressure of the hydrocarbon sample based on the phase state image data and the corresponding pressure data. This method can quickly and accurately acquire the phase change behavior and corresponding pressure data of hydrocarbon samples within a microfluidic chip, thereby obtaining a more accurate bubble point pressure of the hydrocarbon based on the acquired phase change behavior and corresponding pressure data.

Description

Technical Field

[0001] This application relates to the field of oil and gas development technology, and in particular to a method, apparatus and equipment for determining the bubble point pressure of hydrocarbons. Background Technology

[0002] Compared to conventional reservoirs, unconventional oil reservoirs such as tight and shale have pore sizes reduced to hundreds or even tens of nanometers. The fluid phase, flow, and transport behavior within these micro- and nanopores are subject to complex interactions of fluid-structure interaction and interfacial tension, resulting in gas-liquid interaction mechanisms that differ from macroscopic characteristics. In shale and tight oil reservoirs, hydrocarbons are confined within nanopores, and the fluid phase changes with pressure. However, due to the influence of the nanoscale confinement, the fluid phase behavior within nanopores deviates significantly from that under macroscopic conditions, making it difficult to accurately and effectively measure the bubble point pressure of hydrocarbons within the pores of unconventional oil reservoirs such as tight and shale using existing methods.

[0003] There is currently no effective solution to the problem of not being able to accurately and effectively measure the bubble point pressure of hydrocarbons in the pores of unconventional oil reservoirs. Summary of the Invention

[0004] The purpose of this application is to provide a method, apparatus, and device for determining the bubble point pressure of hydrocarbons, in order to solve the problem of the inability to accurately and effectively measure the bubble point pressure of hydrocarbons in the pores of unconventional oil reservoirs.

[0005] To solve the above-mentioned technical problems, the first aspect of this specification provides a method for determining the bubble point pressure of hydrocarbons, including:

[0006] Obtain preset experimental parameters, which include at least preset pressure and preset temperature, and are determined based on the reservoir characteristics of the target reservoir.

[0007] Phase transition simulation was performed on hydrocarbon samples in the target reservoir based on the preset experimental parameters. The phase transition simulation was achieved through a microfluidic device connected to the microfluidic chip corresponding to the target reservoir.

[0008] Acquire phase image data of the hydrocarbon sample under various pressure conditions;

[0009] Based on the image data of each phase and the pressure data corresponding to each phase image, the bubble point pressure of the hydrocarbon sample is determined.

[0010] In some embodiments of this specification, the bubble point pressure of the hydrocarbon sample is determined based on image data of each phase and the corresponding pressure data, including:

[0011] Based on the time corresponding to each phase image data, the phase image data are sorted.

[0012] Based on the sorting results, at least one phase image data of a hydrocarbon sample containing a first phase is determined as the first target image data, wherein the first phase includes gaseous and liquid states;

[0013] The bubble point pressure is determined based on the pressure data corresponding to the first target image data.

[0014] In some embodiments of this specification, determining the bubble point pressure based on pressure data corresponding to the first target image data includes:

[0015] Determine the number of bubbles in each phase image data of the first target image data;

[0016] Select at least one phase image data with the fewest bubbles in the first target image data as the second target image data;

[0017] The earliest phase image data in the second target image data is determined as the third target image data, and the pressure corresponding to the third target image data is determined as the bubble point pressure.

[0018] In some embodiments of this specification, phase transition simulation is performed on hydrocarbon samples in the target reservoir based on the preset experimental parameters, including:

[0019] The microfluidic chip corresponding to the target reservoir is fixed on the microfluidic device, and the airtightness of the microfluidic device is tested.

[0020] After the airtightness test is passed, the inside of the microfluidic chip is evacuated, and the hydrocarbon sample is injected into the microfluidic chip until the microfluidic chip is filled with the hydrocarbon sample, and then the outlet valve is closed.

[0021] By continuously injecting the hydrocarbon sample into the microfluidic chip, the pressure inside the microfluidic chip is adjusted to the preset pressure;

[0022] The temperature of the microfluidic device is adjusted to the preset temperature using a circulating water bath device;

[0023] The hydrocarbon sample inside the microfluidic chip was re-extracted, and a phase transition simulation was performed on the hydrocarbon sample.

[0024] Accordingly, phase image data of the hydrocarbon sample under various pressure conditions are obtained, including:

[0025] When the hydrocarbon sample in the microfluidic chip is re-drawn at a preset speed, the phase state of the hydrocarbon in the microfluidic chip is continuously imaged to obtain phase state image data, and the current pressure data in the microfluidic chip at each imaging moment is recorded.

[0026] In some embodiments of this specification, the microfluidic chip includes: a flow-aiding channel and a blind-end channel, wherein the flow-aiding channel and the blind-end channel are arranged perpendicularly to each other, one end of the blind-end channel connected to the flow-aiding channel is open, and the other end away from the flow-aiding channel is sealed;

[0027] The hydrocarbon sample within the microfluidic chip is re-extracted, and a phase transition simulation is performed on the hydrocarbon sample, including:

[0028] By rapidly re-extracting hydrocarbon samples from the microfluidic chip, and recording the pressure range at the blind-end channel inlet of the microfluidic chip when a phase change occurs in the hydrocarbon sample;

[0029] A hydrocarbon sample is injected into the microfluidic chip, causing the pressure inside the microfluidic chip to exceed the pressure range. The injection is then stopped and stabilized for a first preset time interval.

[0030] The hydrocarbon sample in the microfluidic chip is re-drawn at a preset speed, and the re-drawing is stopped at preset pressure intervals and stabilized at a second preset time interval until the hydrocarbon sample in the microfluidic chip appears in the gas phase.

[0031] In some embodiments of this specification, the hydrocarbon sample includes at least one of the following: crude oil sample, single-component alkane sample, and multi-component alkane mixture sample.

[0032] The second aspect of this specification provides an apparatus for determining the bubble point pressure of hydrocarbons, comprising:

[0033] The first acquisition module is used to acquire preset experimental parameters, which include at least preset pressure and preset temperature, and the preset experimental parameters are determined based on the reservoir characteristics of the target reservoir.

[0034] The simulation module is used to simulate the phase transition of hydrocarbon samples in the target reservoir based on the preset experimental parameters. The phase transition simulation is achieved through a microfluidic device connected to the microfluidic chip corresponding to the target reservoir.

[0035] The second acquisition module is used to acquire phase image data of the hydrocarbon sample under various pressure data.

[0036] The determination module is used to determine the bubble point pressure of the hydrocarbon sample based on the image data of each phase and the pressure data corresponding to each phase image data.

[0037] A third aspect of this specification provides an electronic device, comprising: a memory and a processor, wherein the processor and the memory are communicatively connected to each other, the memory stores computer instructions, and the processor executes the computer instructions to implement the steps of the method described in any of the first aspects.

[0038] A fourth aspect of this specification provides a computer storage medium storing computer program instructions that, when executed by a processor, implement the steps of the method described in any of the first aspects.

[0039] A fifth aspect of this specification provides a computer program product comprising a computer program that, when executed by a processor, implements the steps of the method described in the first aspect.

[0040] Based on the method, apparatus, and equipment for determining the bubble point pressure of hydrocarbons provided in the embodiments of this specification, preset experimental parameters are acquired, including at least preset pressure and preset temperature, and these preset experimental parameters are based on the target reservoir. Phase transition simulation is performed on hydrocarbon samples in the target reservoir based on the preset experimental parameters. The phase transition simulation is achieved through a microfluidic device connected to a microfluidic chip corresponding to the target reservoir. Phase state image data of the hydrocarbon samples under various pressure data are acquired. Based on the phase state image data and the corresponding pressure data, the bubble point pressure of the hydrocarbon samples is determined. This method can accurately and effectively simulate the phase behavior of hydrocarbon samples in the target reservoir, and can quickly and accurately acquire the phase change behavior and corresponding pressure data of the hydrocarbon samples within the microfluidic chip during the simulation process. Therefore, a more accurate bubble point pressure of the hydrocarbons can be obtained based on the acquired phase change behavior and corresponding pressure data, which can provide some support for the subsequent exploitation of unconventional reservoir oilfields. Attached Figure Description

[0041] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in this application. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0042] Figure 1 The diagram shown is a schematic representation of a method for determining the bubble point pressure of hydrocarbons provided in the embodiments of this specification.

[0043] Figure 2 The diagram shown is a schematic representation of a phase transition simulation process provided in an embodiment of this specification.

[0044] Figure 3 The diagram shown is a schematic of a hydrocarbon bubble point pressure measurement system provided in the embodiments of this specification.

[0045] Figure 4 The diagram shown is a schematic of a microfluidic chip provided in an embodiment of this specification;

[0046] Figure 5 The diagram shown is a schematic of a device for determining the bubble point pressure of hydrocarbons provided in an embodiment of this specification.

[0047] Figure 6 The diagram shown is a schematic of an electronic device provided in an embodiment of this specification. Detailed Implementation

[0048] To enable those skilled in the art to better understand the technical solutions in this application, the technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of this application.

[0049] It should be noted that the information and data related to users involved in the embodiments of this specification are all information and data authorized by the user or fully authorized by the relevant parties. Furthermore, the collection, storage, use, processing, transmission, provision, disclosure, and application of the relevant data all comply with relevant laws, regulations, and standards, and necessary confidentiality measures have been taken. They do not violate public order and good morals, and corresponding operation entry points are provided for users or relevant parties to choose to authorize or refuse.

[0050] It should also be noted that in the embodiments of this specification, certain software, components, models and other existing solutions in the industry may be mentioned. These should be regarded as exemplary and are only intended to illustrate the feasibility of implementing the technical solution of this application. However, it does not mean that the applicant has used or necessarily used the solution.

[0051] As mentioned earlier, due to the influence of the nanopore scale of unconventional reservoirs, it is difficult to accurately measure the bubble point pressure of hydrocarbons in the pores using conventional methods.

[0052] Considering that microfluidic technology can utilize microchannels to control and study fluid flow at the micro- and nano-scale, and given its advantages such as in-situ visualization, low sample consumption, short experimental time, and intrinsic safety, this specification provides a method for determining the bubble point pressure of hydrocarbons. This method uses a microfluidic device to measure the phase changes and corresponding pressures of hydrocarbon samples within micro- and nano-scale confinement, enabling rapid and effective phase simulation of hydrocarbons. Based on the simulated data, more accurate bubble point pressure measurements can be obtained, and the data from a single experiment is sufficient without the need for mathematical methods to supplement the data.

[0053] It is understood that the method for determining the bubble point pressure of hydrocarbons provided in this application can be applied to electronic devices, which can refer to electronic devices with data computing, processing, and storage capabilities. Such electronic devices can be terminals such as PCs (Personal Computers), tablets, smartphones, wearable devices, and intelligent robots; they can also be servers. The server can be an independent physical server, a server cluster or distributed system composed of multiple physical servers, or a cloud server providing cloud computing services.

[0054] The method for determining the bubble point pressure of hydrocarbons provided in the embodiments of this specification will be described below with reference to the accompanying drawings.

[0055] Figure 1 The diagram illustrates a method for determining the bubble point pressure of hydrocarbons provided in an embodiment of this specification. While this specification provides method operation steps or apparatus structures as shown in the following embodiments or figures, the method or apparatus may include more or fewer operation steps or module units, either combined or without inventive effort, based on conventional methods or without inventive effort. In steps or structures where there is no logically necessary causal relationship, the execution order of these steps or the module structure of the apparatus is not limited to the execution order or module structure shown in the embodiments or figures of this specification. When the method or module structure is applied in actual devices, servers, or terminal products, it can be executed sequentially or in parallel according to the method or module structure shown in the embodiments or figures (e.g., in a parallel processor or multi-threaded processing environment, or even in a distributed processing or server cluster implementation environment). Figure 1 As shown, it may include:

[0056] S101: Obtain preset experimental parameters, which include at least preset pressure and preset temperature, and are determined based on the reservoir characteristics of the target reservoir.

[0057] It is understandable that different reservoirs have different characteristics such as pore size, porosity, permeability, formation temperature, and formation pressure, which in turn have different effects on the phase changes of hydrocarbons in the reservoir. By determining the preset experimental parameters applicable to the current reservoir based on the reservoir characteristics of the target reservoir, the phase state of hydrocarbons in the target reservoir can be accurately simulated, and thus a more accurate and reliable bubble point pressure can be obtained.

[0058] S102: Based on the preset experimental parameters, a phase transition simulation is performed on a hydrocarbon sample in the target reservoir. The phase transition simulation is achieved through a microfluidic device connected to a microfluidic chip corresponding to the target reservoir.

[0059] It is understood that hydrocarbon samples can be obtained from the target reservoir or formulated based on the chemical properties of hydrocarbons in the target reservoir. Specifically, the hydrocarbon samples can include at least one of the following: crude oil samples, single-component alkane samples, and multi-component alkane mixture samples. The multi-component alkane mixture sample can be an alkane mixture with any components in any proportion, and this mixture can then be used as a hydrocarbon sample for subsequent phase transition simulation.

[0060] S103: Obtain phase image data of the hydrocarbon sample under various pressure data.

[0061] It is understandable that phase image data can be image data of hydrocarbon substances collected during phase simulation at the micro- and nano-scale, such as under a microscope.

[0062] S104: Determine the bubble point pressure of the hydrocarbon sample based on the image data of each phase and the pressure data corresponding to each phase image data.

[0063] In the embodiments of this specification, the phase behavior of hydrocarbon samples in the target reservoir can be accurately and effectively simulated. During the simulation, the phase change behavior of hydrocarbon samples in the microfluidic chip and the corresponding pressure data can be obtained quickly and accurately. Based on the obtained phase change behavior and corresponding pressure data, a more accurate bubble point pressure of hydrocarbons can be obtained, which can provide certain support for the subsequent exploitation of unconventional reservoir oil reservoirs.

[0064] In some embodiments of this specification, determining the bubble point pressure of the hydrocarbon sample based on each phase image data and the pressure data corresponding to each phase image data may include: sorting the phase image data according to the time corresponding to each phase image data; determining, based on the sorting result, at least one phase image data of the hydrocarbon sample containing a first phase as first target image data, where the first phase includes gas and liquid; and determining the bubble point pressure based on the pressure data corresponding to the first target image data.

[0065] In some embodiments of this specification, determining the bubble point pressure based on the pressure data corresponding to the first target image data may include: determining the number of bubbles in each phase image data in the first target image data; selecting at least one phase image data with the fewest bubbles in the first target image data as the second target image data; determining the earliest phase image data in the second target image data as the third target image data, and determining the pressure corresponding to the third target image data as the bubble point pressure.

[0066] It is understandable that when the first bubble appears in the hydrocarbon sample within the microfluidic chip, the current pressure reaches the bubble point pressure. Therefore, by filtering the first target image data, including filtering based on the number of bubbles and time, a third target image data can be obtained. The pressure corresponding to the third target image data can then be used as the bubble point pressure. When determining the number of bubbles in the phase image data within the first target image data, image processing can be used to determine the number of bubbles. For example, image processing software can be used to identify changes in light intensity, thereby identifying bubbles in the image and obtaining the number of bubbles.

[0067] refer to Figure 2 As shown, in some embodiments of this specification, simulating phase transitions of hydrocarbon samples in the target reservoir based on the preset experimental parameters may include:

[0068] S201: Fix the microfluidic chip corresponding to the target reservoir onto the microfluidic device, and perform airtightness testing on the microfluidic device.

[0069] It is understandable that microfluidic chips can be fabricated from single-crystal silicon wafers and quartz glass through anodic bonding. Specifically, the rock formation structure of the target reservoir can be simulated by etching channel patterns on the single-crystal silicon wafer based on the pore characteristics of the target reservoir. In particular, the channel patterns in the microfluidic chip can be designed based on the pore characteristics of the target reservoir; for example, these can be channels with micro- or nano-sized confined spaces or porous media regions. Furthermore, data such as the width and depth of the channels, and the porosity and permeability of the porous media regions can be set based on the pore characteristics of the target reservoir.

[0070] S202: After the airtightness test is passed, the inside of the microfluidic chip is evacuated, and the hydrocarbon sample is injected into the microfluidic chip until the microfluidic chip is filled with the hydrocarbon sample, and then the outlet valve is closed.

[0071] It is understandable that, to avoid the influence of gases in the microfluidic chip on the observation of phase changes in hydrocarbons, it is necessary to ensure the airtightness of the microfluidic device. This can be achieved by evacuating the microfluidic chip and injecting hydrocarbon samples into the chip until the blind-end channel is full before closing the outlet valve. These methods minimize interference from other gases or substances, leading to more accurate bubble point pressure measurements. Specifically, when injecting hydrocarbon samples into the microfluidic chip, the injection can be stopped once the blind-end channel is confirmed to be full, and the outlet valve closed.

[0072] S203: By continuously injecting the hydrocarbon sample into the microfluidic chip, the pressure inside the microfluidic chip is adjusted to the preset pressure.

[0073] Specifically, the preset pressure can be the macroscopic bubble point pressure of the hydrocarbon sample at a preset temperature, which can be determined by conventional bubble point pressure measurement methods.

[0074] S204: Adjust the temperature of the microfluidic device to the preset temperature using a circulating water bath device.

[0075] Specifically, the preset temperature can be determined based on the formation temperature corresponding to the target reservoir.

[0076] S205: Retract the hydrocarbon sample from the microfluidic chip and simulate the phase transition of the hydrocarbon sample.

[0077] Accordingly, acquiring phase image data of the hydrocarbon sample under various pressure conditions may include:

[0078] When the hydrocarbon sample in the microfluidic chip is re-drawn at a preset speed, the phase state of the hydrocarbon in the microfluidic chip is continuously imaged to obtain phase state image data, and the current pressure data in the microfluidic chip at each imaging moment is recorded.

[0079] It is understandable that during bubble point pressure measurement, the microfluidic chip can be continuously imaged during the pressure reduction and / or the waiting period after each pressure point is stopped. This allows for the acquisition of more accurate and reliable phase image data, leading to a more precise bubble point pressure. Furthermore, since the vaporization of hydrocarbon samples generally occurs at the blind end channel inlet, gradually vaporizing towards the blind end, continuous imaging of the microfluidic chip can also capture images of the blind end channel inlet.

[0080] Furthermore, in step S204, after adjusting the temperature of the microfluidic device to a preset temperature, it can be stabilized for a certain period of time before the hydrocarbon sample is re-extracted. For example, it can be stabilized for 15 minutes.

[0081] In some embodiments of this specification, the microfluidic chip includes a flow-aiding channel and a blind-end channel, wherein the flow-aiding channel and the blind-end channel are arranged perpendicularly to each other, the end of the blind-end channel connected to the flow-aiding channel is open, and the end away from the flow-aiding channel is sealed.

[0082] Further, the process of retracting the hydrocarbon sample from the microfluidic chip and simulating the phase change of the hydrocarbon sample can include: rapidly retracting the hydrocarbon sample from the microfluidic chip and recording the pressure range at the blind end channel inlet of the microfluidic chip when the hydrocarbon sample undergoes a phase change; injecting the hydrocarbon sample into the microfluidic chip so that the pressure inside the microfluidic chip is greater than the pressure range, stopping the injection and stabilizing for a first preset time interval; retracting the hydrocarbon sample from the microfluidic chip at a preset speed, stopping the retraction at preset pressure intervals and stabilizing for a second preset time interval, until the hydrocarbon sample in the microfluidic chip appears in a gas phase.

[0083] The first and second preset time intervals can be used to stabilize the phase state of hydrocarbon samples after pressure changes within the microfluidic chip, resulting in more accurate and reliable phase state image data. Specifically, the first preset time interval can be longer than the second preset time interval. For example, the first preset time interval can be 10 minutes, and the second preset time interval can be 1 minute.

[0084] Specifically, the preset speed can be determined based on the pressure range at which the hydrocarbon sample undergoes a phase change. For example, after determining the pressure range, a preset pressure interval corresponding to each aspiration can be determined, and a preset speed can be determined by combining the preset pressure interval, the amount of hydrocarbon material aspirated at the preset pressure interval, and the parameters of the injection device used for aspiration. Furthermore, a microfluidic device can be used to perform multiple cycles of aspiration-injection of the hydrocarbon sample, and the preset speed can be adjusted based on the pressure data measured in each cycle to obtain a more accurate bubble point pressure.

[0085] Furthermore, by cyclically determining the pressure range, and within this range, performing back-extraction of hydrocarbon samples and adjusting the preset pressure interval, the pressure range can be continuously narrowed to obtain more accurate bubble point pressure measurements. Specifically, after raising the temperature of the microfluidic device to the preset temperature and stabilizing it for a certain period of time, the following process can be repeated:

[0086] Hydrocarbon samples are aspirated from the microfluidic chip at an initial preset rate using a micropump, reducing the internal pressure. Simultaneously, the phase changes of the hydrocarbon sample within the chip are observed using a microscopic observation device, and the current pressure range at which vaporization occurs is recorded. Hydrocarbon samples are then injected into the microfluidic chip using the micropump, increasing the internal pressure to above a predetermined current pressure range. Injection is stopped, and the chip is stabilized at this state for a first preset time interval. The initial preset rate is then reduced by a preset rate difference, and the hydrocarbon sample is aspirated from the microfluidic chip at the reduced rate, further reducing the internal pressure. Again, the phase changes of the hydrocarbon sample within the chip are observed using a microscopic observation device, and the current pressure range at which vaporization occurs is recorded. This process of injection, rate determination, and aspiration is repeated to continuously narrow the pressure range, and the bubble point pressure of the hydrocarbon sample is measured.

[0087] In the embodiments of this specification, the bubble point pressure in tens of nanometer pores can be measured by a microfluidic device, which has a wider range of applications. Furthermore, the bubble point pressure is measured by a visual method through a microfluidic chip during the experiment. Using the microfluidic chip in the embodiments of this specification, the entire pipeline is uniformly the fluid to be measured, which is not affected by other substances and the measurement is rapid.

[0088] This specification provides a hydrocarbon bubble point pressure measurement system and a method for measuring hydrocarbon bubble point pressure through its embodiments. The following describes the methods in conjunction with... Figure 3 This paper introduces the hydrocarbon bubble point pressure measurement system and the measurement method for hydrocarbon bubble point pressure.

[0089] The system may include a microfluidic experimental platform, a microfluidic chip, and a circulating water bath. The microfluidic experimental platform includes a fluid control device, a chip fixation device, and a microscopic observation device.

[0090] The fluid control device is used to control the flow rate of the hydrocarbon sample to be tested in the microfluidic chip. It can also control the injection pressure by injecting and withdrawing hydrocarbons, that is, to control the pressure in the microfluidic chip.

[0091] The chip fixing device is used to fix the microfluidic chip 1 in the fixture, ensuring that neither chip movement nor leakage of hydrocarbon substances occurs within the device.

[0092] The microscopic observation device 2 is used for in-situ real-time observation of the phase changes of hydrocarbon samples in the pores of a microfluidic chip under different pressures. At the same time, a camera can be used to capture the gasification process of hydrocarbons, and a sensor can be used to record the pressure at each time point.

[0093] Specifically, the fluid control device includes a hydrocarbon injection device and a vacuum device. The hydrocarbon injection device includes at least a micro-injection pump 3 and a syringe, and the vacuum device includes at least a vacuum pump 4. A pressure sensor 5 is used to measure the pressure inside the chip throughout the testing process.

[0094] The microfluidic chip has two connection ports for connecting to external pipelines, namely the first connection port 6 and the second connection port 7. The first connection port 6 is connected to the syringe of the hydrocarbon injection device, and a pressure sensor 5 is installed on the pipeline between the syringe and the first connection port 6. When the hydrocarbon sample is injected or withdrawn using the micro-injection pump 3, the pressure sensor 5 can monitor the pressure of the fluid at this time. The micro-injection pump 3 can accurately control the amount of hydrocarbon injected into the chip, and can also make the pressure inside the chip measured by the pressure sensor 3 more accurate.

[0095] The second connection port 7 is connected to a vacuum pump 4 with a vacuum pumping device, and an outlet valve 8 is installed on the pipeline between the vacuum pump 4 and the second connection port 7. The vacuum pump 4 can evacuate the gas inside the chip before injecting hydrocarbon samples into the chip. This not only helps to quickly fill the entire chip when injecting hydrocarbon samples, but also reduces the influence of the original gas inside the chip on pressure measurement.

[0096] The microfluidic chip is fabricated by anodic bonding of a single-crystal silicon wafer and quartz glass. It simulates the rock formation structure in a real oil reservoir by etching channel patterns on the single-crystal silicon wafer. Depending on the specific requirements, the channel patterns can be designed as micro- or nano-sized confined channels or porous media regions. The width, depth, porosity, and permeability of these channels and porous media regions can be customized as needed. This microfluidic chip has the advantages of high temperature and high pressure resistance, capable of withstanding pressures up to 40 MPa and temperatures up to 250°C. The channel patterns used in the embodiments of the specification can include a combination of larger flow-aiding channels (200 μm wide, 100 μm deep) and linear closed blind-end channels (10 μm wide, with varying depths depending on the chip, including 1 μm, 200 nm, 100 nm, and 30 nm). For details, please refer to [reference needed]. Figure 4 As shown.

[0097] The microscopic observation device 2 may include at least an LED light source, a microscope, a CCD high-speed camera, and a computer. The LED light source provides excitation light, ensuring sufficient illumination during observation. The microscope and CCD high-speed camera are tightly integrated, transmitting real-time captured images to the computer, allowing for direct observation of the dynamic internal workings of the microfluidic chip on the computer's screen. The microscope is precisely mounted directly above the chip mounting device, ensuring accurate observation.

[0098] Furthermore, the system may also include an XYZ three-axis slide for fine-tuning the position of the chip fixing device, which makes it easier to observe the phase state of hydrocarbons inside the microfluidic chip.

[0099] Furthermore, based on Figure 3 The hydrocarbon bubble point pressure measurement steps corresponding to the hydrocarbon bubble point pressure testing system are as follows:

[0100] S1: Fix the microfluidic chip in the chip fixing device, connect the pipeline and the equipment, build the microfluidic experimental platform, and check the airtightness of the microfluidic experimental platform;

[0101] S2: Use a vacuum pump to evacuate the inside of the microfluidic chip, inject hydrocarbon samples into the chip until the blind end channel is filled with hydrocarbons, and then close the outlet valve;

[0102] S3: Continue to inject hydrocarbon samples using a micro-injection pump, so that the pressure inside the chip continues to rise until the pressure displayed by the pressure sensor exceeds the macroscopic bubble point pressure of the hydrocarbon at the experimental temperature, then stop injecting the oil.

[0103] S4: Turn on the circulating water bath device to raise the overall temperature of the chip fixing device to the required temperature for the experiment, and then stabilize it for 15 minutes.

[0104] S5: The hydrocarbon sample is rapidly re-drawn by a micro-injection pump to reduce the internal pressure of the chip. At the same time, the vaporization phenomenon of the hydrocarbon sample exiting the blind end channel inlet of the chip is observed by a microscopic observation device, and the approximate pressure range when the vaporization phenomenon occurs is recorded.

[0105] S6: Use a micro-injection pump to inject a hydrocarbon sample into the chip, so that the internal pressure of the chip increases to above the pressure range recorded in step (5), stop the injection and stabilize in this state for 10 minutes;

[0106] S7: Use a micro-injection pump to slowly re-pump the hydrocarbon sample and take pictures with a microscope. Stop the micro-injection pump at certain pressure intervals and stabilize for about 1 minute until the gas phase appears in the microscope image. Record the pressure displayed by the pressure sensor at this time and save the hydrocarbon vaporization process captured by the microscope.

[0107] In the embodiments of this specification, by utilizing the process visualization and micro / nanoscale structure characteristics of microfluidic technology, a direct criterion for the bubble point pressure of hydrocarbons at the micro / nanoscale can be obtained by observing the phase changes of hydrocarbons in situ in real time. The embodiments in this specification utilize microfluidic technology to observe the phase changes of hydrocarbons inside the chip in situ in real time, directly correlating the vaporization behavior of hydrocarbons with the actual measured bubble point pressure. Simultaneously, the vaporization process of hydrocarbon mixtures can be recorded using a microscopic observation device. By changing the channel size or pattern design of the microfluidic chip, it is possible to easily simulate channels or porous media regions with different micro / nano confinement scales, porosities, and permeabilities, thereby measuring the bubble point pressure of hydrocarbons under various conditions. The measurement process requires a small amount of hydrocarbon sample, saving resources; the measurement procedure is simple, easy to operate, and requires little experimental time; a single experiment provides sufficient data, eliminating the need for mathematical supplementation, and the experimental method has good repeatability; it is applicable to various types of hydrocarbons, and the hydrocarbon samples used can be formulated according to requirements. The hydrocarbon samples used can be crude oil, single-component alkanes, or mixtures of alkanes with any components and proportions; it is applicable to bubble point pressure measurements under various reservoir environmental temperatures and pressures, and the set temperature, pressure, and other conditions can be easily changed within the device's tolerance limits.

[0108] The following is combined Figure 3 The above-mentioned hydrocarbon bubble point pressure measurement system and measurement method are described with reference to a specific embodiment:

[0109] This embodiment provides a micro / nano-scale hydrocarbon bubble point pressure measurement system based on microfluidic technology, such as... Figure 3 As shown. The measurement system may include: a microfluidic chip 1, a circulating water bath device, a fluid control device, a chip fixing device, and a microscopic observation device 2. The chip fixing device is used to fix the chip in a fixture, ensuring that neither chip movement nor leakage of hydrocarbon substances occurs within the device.

[0110] The fluid control device includes a micro-injection pump 3, a syringe, a vacuum pump 4, and a pressure sensor 5.

[0111] The microfluidic chip is designed with two connection ports, a first connection port 6 and a second connection port 7, for connection to a fluid control device. The first connection port 1 is directly connected to a syringe. The other two ends of the syringe are connected to a microinjection pump 3 and a pressure sensor 5 via tubing, respectively. The other end of the pressure sensor 5 is connected to a microscopic observation device 2 to transmit the measured internal pressure of the chip to the microscopic observation device 2 for pressure observation. The second connection port 7 is connected to a vacuum pump 4 via an outlet valve 8 to evacuate the inside of the microfluidic chip before injecting hydrocarbon substances.

[0112] The chip fixture is connected to an external circulating water bath, which allows for temperature control during experiments, ensuring the microfluidic chip remains within a set temperature environment. The main body of the chip fixture is a temperature-controlled and pressure-resistant clamping device for high-throughput, visualized microfluidic chips. From top to bottom, it consists of a stainless steel frame cover, a quartz glass cover, a clamping platform, and an XYZ three-axis slide. Pressure-resistant connectors and fasteners such as O-rings, NPT adapters, ferrules, and screws are used between the various components.

[0113] The channel pattern of the microfluidic chip consists of a combination of flow-aiding channels (200 μm wide and 100 μm deep) and linear closed blind-end channels (10 μm wide, with depth designed based on chip depth). Its specific structure is described in [reference needed]. Figure 4 As shown.

[0114] The microscopic observation device 2 includes an LED light source, a microscope, a CCD high-speed camera, and a computer. The microscope and CCD high-speed camera are tightly integrated to transmit real-time captured images to the computer, which displays the dynamic situation inside the microfluidic chip on the computer screen. The microscope is precisely mounted directly above the chip holder, which is also equipped with an XYZ three-axis slide for fine-tuning the position of the chip holder.

[0115] The micro-nano cross-scale hydrocarbon bubble point pressure measurement system based on the above microfluidic technology measures the bubble point pressure of n-pentane (C5H9) at different depth channels at 70°C, including the following operation steps:

[0116] S1: Will have Figure 4 The microfluidic chip with the channel pattern is fixed in the chip fixing device, the pipeline is connected to the equipment, the microfluidic experimental platform is built, and the airtightness of the microfluidic experimental platform is checked.

[0117] S2: Use a vacuum pump to evacuate the inside of the microfluidic chip, inject the n-pentane sample into the chip until the blind end channel is filled with hydrocarbons, and then close the outlet valve.

[0118] S3: Continue to inject n-pentane using the micro-injection pump, so that the pressure inside the chip continues to rise until the pressure displayed by the pressure sensor exceeds 0.2813 MPa, then stop injecting n-pentane;

[0119] S4: Turn on the circulating water bath device to raise the overall temperature of the chip fixing device to 70℃ and stabilize it for 15 minutes.

[0120] S5: Rapidly re-draw n-pentane using a micro-injection pump to reduce the internal pressure of the chip. Simultaneously, observe the vaporization of n-pentane at the blind end channel inlet of the chip using a microscopic observation device and record the approximate pressure range when the vaporization occurs.

[0121] S6: Use a micro-injection pump to inject n-pentane into the chip, increasing the internal pressure of the chip to above the pressure range recorded in S5, stop the injection and stabilize in this state for 10 minutes;

[0122] S7: Slowly re-pump n-pentane using a micro-injection pump and photograph it with a microscope. Stop the micro-injection pump at regular intervals and stabilize for about 1 minute until the gas phase appears in the microscope image. Record the pressure displayed by the pressure sensor at this time and save the n-pentane vaporization process captured by the microscope. Repeat the experiment three times and take the average value to obtain the bubble point pressure of n-pentane at different depth channels at 70℃.

[0123] Based on the method for determining the bubble point pressure of hydrocarbons described above, one or more embodiments of this specification also provide an apparatus for determining the bubble point pressure of hydrocarbons. The apparatus may include devices (including distributed systems), software (applications), modules, plug-ins, servers, clients, etc., using the methods described in the embodiments of this specification, combined with necessary hardware implementation. Based on the same innovative concept, the apparatuses in one or more embodiments provided in this specification are as described in the following embodiments. Since the implementation schemes and methods for solving the problem by the apparatus are similar, the implementation of the specific apparatus in the embodiments of this specification can refer to the implementation of the foregoing method, and repeated details will not be elaborated further. As used below, the terms "unit" or "module" can refer to a combination of software and / or hardware that performs a predetermined function. Although the apparatus described in the following embodiments is preferably implemented in software, hardware implementation, or a combination of software and hardware, is also possible and contemplated. Figure 5 The diagram shown is a schematic representation of a device for determining the bubble point pressure of hydrocarbons provided in an embodiment of this specification. Figure 5 As shown, the apparatus 500 for determining the bubble point pressure of hydrocarbons may include:

[0124] The first acquisition module 501 is used to acquire preset experimental parameters, which include at least preset pressure and preset temperature, and are determined based on the reservoir characteristics of the target reservoir.

[0125] The simulation module 502 is used to simulate the phase transition of hydrocarbon samples in the target reservoir based on the preset experimental parameters. The phase transition simulation is achieved by a microfluidic device connected to the microfluidic chip corresponding to the target reservoir.

[0126] The second acquisition module 503 is used to acquire phase image data of the hydrocarbon sample under various pressure data.

[0127] The determination module 504 is used to determine the bubble point pressure of the hydrocarbon sample based on the image data of each phase and the pressure data corresponding to each phase image data.

[0128] In some embodiments of this specification, the determining module 504 is specifically used to: sort the phase image data based on the time corresponding to each phase image data; determine, based on the sorting result, at least one phase image data of a hydrocarbon sample containing a first phase as first target image data, the first phase including gas and liquid; and determine the bubble point pressure based on the pressure data corresponding to the first target image data.

[0129] In some embodiments of this specification, determining the bubble point pressure based on the pressure data corresponding to the first target image data includes: determining the number of bubbles in each phase image data in the first target image data; selecting at least one phase image data with the fewest bubbles in the first target image data as the second target image data; determining the earliest phase image data in the second target image data as the third target image data, and determining the pressure corresponding to the third target image data as the bubble point pressure.

[0130] In some embodiments of this specification, the simulation module 502 is specifically used for: fixing the microfluidic chip corresponding to the target reservoir to the microfluidic device and performing an airtightness test on the microfluidic device; after the airtightness test is passed, evacuating the inside of the microfluidic chip and injecting the hydrocarbon sample into the microfluidic chip until the microfluidic chip is filled with the hydrocarbon sample, and then closing the outlet valve; adjusting the pressure inside the microfluidic chip to the preset pressure by continuously injecting the hydrocarbon sample into the microfluidic chip; adjusting the temperature of the microfluidic device to the preset temperature using a circulating water bath device; and re-extracting the hydrocarbon sample from the microfluidic chip to simulate a phase change in the hydrocarbon sample.

[0131] Accordingly, the second acquisition module 503 is specifically used to: when the hydrocarbon sample in the microfluidic chip is re-drawn at a preset speed, continuously image the phase state of the hydrocarbon in the microfluidic chip to obtain phase state image data, and record the current pressure data in the microfluidic chip at each imaging moment.

[0132] In some embodiments of this specification, the microfluidic chip includes a flow-aiding channel and a blind-end channel, wherein the flow-aiding channel and the blind-end channel are arranged perpendicularly to each other, the end of the blind-end channel connected to the flow-aiding channel is open, and the end away from the flow-aiding channel is sealed.

[0133] Correspondingly, when the simulation module 502 retracts the hydrocarbon sample from the microfluidic chip to simulate the phase change of the hydrocarbon sample, it is used to: rapidly retract the hydrocarbon sample from the microfluidic chip and record the pressure range at the blind end channel inlet of the microfluidic chip when the hydrocarbon sample undergoes a phase change; inject the hydrocarbon sample into the microfluidic chip so that the pressure inside the microfluidic chip is greater than the pressure range, stop the injection and stabilize for a first preset time interval; retract the hydrocarbon sample from the microfluidic chip at a preset speed, and stop retracting every preset pressure interval and stabilize for a second preset time interval until the hydrocarbon sample in the microfluidic chip appears in the gas phase.

[0134] In some embodiments of this specification, the hydrocarbon sample includes at least one of the following: crude oil sample, single-component alkane sample, and multi-component alkane mixture sample.

[0135] The descriptions and functions of the above modules can be understood by referring to the section on methods for determining the bubble point pressure of hydrocarbons, and will not be repeated here.

[0136] This application also provides an electronic device, such as... Figure 6 As shown, the electronic device may include a processor 601 and a memory 602, wherein the processor 601 and the memory 602 may be connected via a bus or other means. Figure 6 Taking the example of a connection between China and Israel via a bus.

[0137] Processor 601 may be a central processing unit (CPU). Processor 601 may also be other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, or combinations thereof.

[0138] Memory 602, as a non-transitory computer-readable storage medium, can be used to store non-transitory software programs, non-transitory computer-executable programs, and modules, such as the program instructions / modules corresponding to the method for determining the bubble point pressure of hydrocarbons in this embodiment of the invention (e.g., Figure 5The first acquisition module 501, simulation module 502, second acquisition module 503, and determination module 504 are shown. The processor 601 executes various functional applications and data processing by running non-transient software programs, instructions, and modules stored in the memory 602, thereby realizing the method for determining the hydrocarbon bubble point pressure in the above method embodiments.

[0139] The memory 602 may include a program storage area and a data storage area. The program storage area may store the operating system and applications required for at least one function; the data storage area may store data created by the processor 601, etc. Furthermore, the memory 602 may include high-speed random access memory and may also include non-transitory memory, such as at least one disk storage device, flash memory device, or other non-transitory solid-state storage device. In some embodiments, the memory 602 may optionally include memory remotely located relative to the processor 601, and these remote memories may be connected to the processor 601 via a network. Examples of such networks include, but are not limited to, the Internet, corporate intranets, local area networks, mobile communication networks, and combinations thereof.

[0140] The one or more modules are stored in the memory 602, and when executed by the processor 601, they perform the following method for determining the bubble point pressure of hydrocarbons:

[0141] Preset experimental parameters are obtained, including at least a preset pressure and a preset temperature, which are determined based on the reservoir characteristics of the target reservoir. Phase transition simulation is performed on hydrocarbon samples in the target reservoir based on the preset experimental parameters. The phase transition simulation is achieved through a microfluidic device connected to a microfluidic chip corresponding to the target reservoir. Phase image data of the hydrocarbon samples at various pressures are obtained. Based on the phase image data and the corresponding pressure data, the bubble point pressure of the hydrocarbon samples is determined.

[0142] The specific details of the aforementioned electronic device can be understood by referring to the relevant descriptions and effects in the above method embodiments, and will not be repeated here.

[0143] This specification also provides a computer storage medium storing computer program instructions that, when executed, implement the steps of the method for determining the bubble point pressure of hydrocarbons described above.

[0144] Those skilled in the art will understand that all or part of the processes in the methods of the above embodiments can be implemented by a computer program instructing related hardware. The program can be stored in a computer-readable storage medium, and when executed, it can include the processes of the embodiments of the above methods. The storage medium can be a magnetic disk, optical disk, read-only memory (ROM), random access memory (RAM), flash memory, hard disk drive (HDD), or solid-state drive (SSD), etc.; the storage medium can also include combinations of the above types of memory.

[0145] The various embodiments in this specification are described in a progressive manner. For the same or similar parts between the various embodiments, please refer to each other. The focus of each embodiment is to describe the differences from other embodiments.

[0146] The systems, devices, modules, or units described in the above embodiments can be implemented by computer chips or entities, or by products with certain functions.

[0147] For ease of description, the above devices are described separately by function as various units. Of course, in implementing this application, the functions of each unit can be implemented in one or more software and / or hardware.

[0148] As can be seen from the above description of the embodiments, those skilled in the art can clearly understand that this application can be implemented by means of software plus necessary general-purpose hardware platforms. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product can be stored in a storage medium, such as ROM / RAM, magnetic disk, optical disk, etc., and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute certain parts of the methods of various embodiments of this application.

[0149] This application can be used in a wide variety of general-purpose or special-purpose computer system environments or configurations. For example: personal computers, server computers, handheld or portable devices, tablet devices, multiprocessor systems, microprocessor-based systems, set-top boxes, programmable consumer electronics devices, network PCs, minicomputers, mainframe computers, distributed computing environments including any of the above systems or devices, etc.

[0150] This application can be described in the general context of computer-executable instructions, such as program modules, that are executed by a computer. Generally, program modules include routines, programs, objects, components, data structures, etc., that perform a specific task or implement a specific abstract data type. This application can also be practiced in distributed computing environments where tasks are performed by remote processing devices connected via a communication network. In distributed computing environments, program modules can reside in local and remote computer storage media, including storage devices.

[0151] Although this application has been described through embodiments, those skilled in the art will know that this application has many modifications and variations without departing from the spirit of this application, and it is intended that the appended claims cover such modifications and variations without departing from the spirit of this application.

Claims

1. A method for determining the bubble point pressure of hydrocarbons, characterized in that, include: Obtain preset experimental parameters, which include at least preset pressure and preset temperature, and are determined based on the reservoir characteristics of the target reservoir. Phase transition simulation was performed on hydrocarbon samples in the target reservoir based on the preset experimental parameters. The phase transition simulation was achieved through a microfluidic device connected to the microfluidic chip corresponding to the target reservoir. Acquire phase image data of the hydrocarbon sample under various pressure conditions; Based on the image data of each phase and the pressure data corresponding to each phase image, the bubble point pressure of the hydrocarbon sample is determined.

2. The method for determining the bubble point pressure of hydrocarbons according to claim 1, characterized in that, Based on the image data of each phase and the corresponding pressure data, the bubble point pressure of the hydrocarbon sample is determined, including: Based on the time corresponding to each phase image data, the phase image data are sorted. Based on the sorting results, at least one phase image data of a hydrocarbon sample containing a first phase is determined as the first target image data, wherein the first phase includes gaseous and liquid states; The bubble point pressure is determined based on the pressure data corresponding to the first target image data.

3. The method for determining the bubble point pressure of hydrocarbons according to claim 2, characterized in that, Determining the bubble point pressure based on the pressure data corresponding to the first target image data includes: Determine the number of bubbles in each phase image data of the first target image data; Select at least one phase image data with the fewest bubbles in the first target image data as the second target image data; The earliest phase image data in the second target image data is determined as the third target image data, and the pressure corresponding to the third target image data is determined as the bubble point pressure.

4. The method for determining the bubble point pressure of hydrocarbons according to claim 1, characterized in that, Phase transition simulations were performed on hydrocarbon samples from the target reservoir based on the preset experimental parameters, including: The microfluidic chip corresponding to the target reservoir is fixed on the microfluidic device, and the airtightness of the microfluidic device is tested. After the airtightness test is passed, the inside of the microfluidic chip is evacuated, and the hydrocarbon sample is injected into the microfluidic chip until the microfluidic chip is filled with the hydrocarbon sample, and then the outlet valve is closed. By continuously injecting the hydrocarbon sample into the microfluidic chip, the pressure inside the microfluidic chip is adjusted to the preset pressure; The temperature of the microfluidic device is adjusted to the preset temperature using a circulating water bath device; The hydrocarbon sample inside the microfluidic chip was re-extracted, and a phase transition simulation was performed on the hydrocarbon sample. Accordingly, phase image data of the hydrocarbon sample under various pressure conditions are obtained, including: When the hydrocarbon sample in the microfluidic chip is re-drawn at a preset speed, the phase state of the hydrocarbon in the microfluidic chip is continuously imaged to obtain phase state image data, and the current pressure data in the microfluidic chip at each imaging moment is recorded.

5. The method for determining the bubble point pressure of hydrocarbons according to claim 4, characterized in that, The microfluidic chip includes a flow-aiding channel and a blind-end channel, wherein the flow-aiding channel and the blind-end channel are arranged perpendicularly to each other, the end of the blind-end channel connected to the flow-aiding channel is open, and the end away from the flow-aiding channel is sealed; The hydrocarbon sample within the microfluidic chip is re-extracted, and a phase transition simulation is performed on the hydrocarbon sample, including: By rapidly re-extracting hydrocarbon samples from the microfluidic chip, and recording the pressure range at the blind end channel inlet of the microfluidic chip when a phase change occurs in the hydrocarbon sample; A hydrocarbon sample is injected into the microfluidic chip, causing the pressure inside the microfluidic chip to exceed the pressure range. The injection is then stopped and stabilized for a first preset time interval. The hydrocarbon sample in the microfluidic chip is re-drawn at a preset speed, and the re-drawing is stopped at preset pressure intervals and stabilized at a second preset time interval until the hydrocarbon sample in the microfluidic chip appears in the gas phase.

6. The method for determining the bubble point pressure of hydrocarbons according to claim 1, characterized in that, The hydrocarbon sample includes at least one of the following: crude oil sample, single-component alkane sample, and multi-component alkane mixture sample.

7. A device for determining the bubble point pressure of hydrocarbons, characterized in that, include: The first acquisition module is used to acquire preset experimental parameters, which include at least preset pressure and preset temperature, and the preset experimental parameters are determined based on the reservoir characteristics of the target reservoir. The simulation module is used to simulate the phase transition of hydrocarbon samples in the target reservoir based on the preset experimental parameters. The phase transition simulation is achieved through a microfluidic device connected to the microfluidic chip corresponding to the target reservoir. The second acquisition module is used to acquire phase image data of the hydrocarbon sample under various pressure data. The determination module is used to determine the bubble point pressure of the hydrocarbon sample based on the image data of each phase and the pressure data corresponding to each phase image data.

8. An electronic device, characterized in that, include: A memory and a processor, the processor and the memory being communicatively connected to each other, the memory storing computer instructions, the processor executing the computer instructions to implement the steps of the method according to any one of claims 1 to 6.

9. A computer storage medium, characterized in that, The computer storage medium stores computer program instructions, which, when executed by a processor, implement the steps of the method according to any one of claims 1 to 6.

10. A computer program product, characterized in that, The computer program product includes a computer program that, when executed by a processor, implements the steps of the method according to any one of claims 1 to 6.

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