Method, system, equipment and medium for evaluating influence of wellbore dirt on organic solid phase deposition

Abstract

The invention relates to the technical field of oil and gas field development, and discloses a method, a system, equipment and a medium for evaluating the influence of wellbore dirt on organic solid phase deposition. The method comprises the steps of determining temperature fields corresponding to different wellbore positions of a single well, correspondingly setting a first temperature according to the temperature fields where the different wellbore positions are located, cooling at a set speed according to the first temperature, recording the change condition of differential heat flow to the temperature in real time, and drawing differential scanning calorimetry curves under the different wellbore positions when a second temperature is reached, determining a wax precipitation point and an interpolation base line of a wellbore temperature interval based on differential scanning calorimetry curves at different wellbore positions, further determining the wax content in the process from the well bottom to the wellbore, further obtaining the organic solid phase deposition in the crude oil at different wellbore positions, and calculating the organic solid phase deposition in the crude oil based on the organic solid phase deposition in the crude oil at different wellbore positions. And evaluating the influence of wellbore dirt on organic solid-phase deposition in crude oil. The method truly and accurately simulates the influence of different shaft positions on organic solid phase deposition.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of oil and gas field development, in particular to an evaluation method, system, device and medium for the influence of wellbore fouling on organic solid phase deposition. BACKGROUND

[0002] In the past decade, ultra-deep oil and gas discoveries have mainly occurred in the Tarim Basin, Junggar Basin and Sichuan Basin. With the development of deep / ultra-deep oil and gas exploration, oil and gas well wax deposition and asphaltene deposition have become increasingly prominent. Since 2014, wellbore foreign matter (organic solid phase) plugging problems have gradually emerged in the platform area of the Tarim Basin, concentrated in the Fumin and Donghe areas, and similar problems have also occurred in the Yudong and Bozhi areas in recent years. The cumulative plugging well ratio is over 20%. After the wellbore is plugged by foreign matter, it affects the production, causes problems such as production layer testing difficulty and ground pipeline burst, and has become a key factor restricting the safe and stable production of oil wells. Wellbore fouling can affect the production and efficiency of oil wells. By evaluating the influence of fouling on organic solid phase deposition, measures can be taken to reduce fouling and improve the extraction efficiency of crude oil.

[0003] The Chinese invention patent application file with the application publication number CN113447641A discloses a method for reconstructing the wax precipitation point of a formation waxy crude oil, which also obtains the wax precipitation point of the reconstructed crude oil through differential scanning calorimetry and numerical simulation. The Chinese invention patent application file with the application publication number CN114509524A discloses a method for determining the precipitation curve between asphaltene wax precipitation temperature and wax precipitation amount. Differential scanning calorimetry is widely recognized in the industry for determining the wax precipitation point of a single crude oil. However, in actual production processes, especially in oil and gas wells with formation fouling, the wax content and wax precipitation point determined by the crude oil differential scanning calorimeter differ by more than 10℃ from the actual wax precipitation point. Relying solely on single crude oil for wax content testing cannot truly reflect the wax precipitation conditions in the oil and gas production site. SUMMARY

[0004] In view of the deficiencies of the prior art, the present application provides an evaluation method, system, device and medium for the influence of wellbore fouling on organic solid phase deposition, which truly simulates and evaluates the influence of fouling and fouling amount at different temperatures and pressures on the wax content of crude oil at different positions in the wellbore, and plays an important role in promoting the understanding of crude oil waxing in oilfield sites.

[0005] The purpose of the present application is achieved by the following technical solutions:

[0006] In a first aspect, the present application provides an evaluation method for the influence of wellbore fouling on organic solid phase deposition, comprising:

[0007] determining the temperature field corresponding to different wellbore positions of a single well, and setting a first temperature according to the temperature field corresponding to different wellbore positions;

[0008] The temperature is reduced at a set rate based on the first temperature, and the change of differential heat flow with temperature is recorded in real time until the second temperature is reached. Based on the recorded change of differential heat flow with temperature, differential scanning calorimetry curves are plotted at different well locations.

[0009] The wax precipitation point and the interpolation baseline of the wellbore temperature range are determined based on the differential scanning calorimetry curves at different wellbore locations. The wax precipitation enthalpy of the crude oil sample at that wellbore location is determined based on the wax precipitation point and the interpolation baseline of the wellbore temperature range. The wax content during the process from the bottom of the well to the wellbore is determined by the wax precipitation enthalpy and the organic solid phase blockage. The amount of organic solid phase deposition in the crude oil at different wellbore locations is then obtained. The organic solid phase blockage includes organic solid phase and wellbore fouling.

[0010] The impact of wellbore fouling on the deposition of organic solids in crude oil was evaluated based on the amount of organic solids deposited at different wellbore locations.

[0011] As a further improvement of the present invention, the step of cooling down at a set rate according to the first temperature and recording the change of differential heat flow with respect to temperature in real time specifically includes: using a differential scanning calorimeter to control the temperature in the well location area to decrease at a set rate, and detecting the change of differential heat flow with respect to temperature at the well location.

[0012] As a further improvement of the present invention, the first temperature is the initial temperature at the wellbore location, and the second temperature is set to -30°C.

[0013] As a further improvement of the present invention, the step of determining the wax precipitation enthalpy of the crude oil sample at the wellbore location based on the interpolation baseline of the wax precipitation point and the wellbore temperature range includes: selecting the interpolation baseline from the wax precipitation point to the wellbore temperature range, and using the ratio of the peak area enclosed by the differential scanning calorimetry curve and the mass of the crude oil sample as the wax precipitation enthalpy of the crude oil sample.

[0014] As a further improvement of the present invention, the wax precipitation point is the intersection of the high-temperature exothermic baseline of the differential scanning calorimetry curve and the extension line of the first front line, and both the high-temperature exothermic baseline and the first front line deviate from the exothermic baseline.

[0015] As a further improvement of the present invention, the step of determining the wax content in the process from the bottom of the well to the wellbore by means of the wax precipitation enthalpy and the organic solid phase blockage includes: determining the wax content in the process from the bottom of the well to the wellbore by means of the ratio of the sample precipitation enthalpy to the crystallization heat of the organic solid phase blockage, and obtaining the amount of organic solid phase deposition in the crude oil.

[0016] As a further improvement of the present invention, the evaluation of the effect of wellbore fouling on the deposition of organic solid phase in crude oil based on the amount of organic solid phase deposition in crude oil at different wellbore locations includes: after obtaining the amount of organic solid phase deposition in crude oil at different wellbore locations, obtaining the wellbore fouling in crude oil at different wellbore locations, obtaining the wellbore fouling precipitation results at different temperatures using an orthogonal polarized light microscope, and determining the content and particle size of wellbore fouling at different temperatures based on the precipitation results;

[0017] The precipitation results of crude oil at different well locations under corresponding temperatures when there is no well fouling were obtained, and the corresponding amount of organic solid phase deposition was obtained based on the precipitation results;

[0018] The amount of organic solids deposited with wellbore fouling at different temperatures was compared with that without wellbore fouling, and the impact of wellbore fouling on the wax content of crude oil was evaluated based on the comparison results.

[0019] Secondly, the present invention also provides an evaluation system for the impact of wellbore fouling on organic solid phase deposition, comprising:

[0020] The wellbore temperature setting module is used to determine the temperature field corresponding to different wellbore locations in a single well, and set the first temperature according to the temperature field corresponding to different wellbore locations.

[0021] The data simulation module is used to cool down at a set rate according to the first temperature, record the changes in temperature with respect to differential heat flow in real time until the second temperature is reached, and plot the differential scanning calorimetry curves at different well locations based on the recorded changes in temperature with respect to differential heat flow.

[0022] The organic solids deposition calculation module determines the wax precipitation point and the interpolation baseline of the wellbore temperature range based on the differential scanning calorimetry curves at different wellbore locations. It then determines the wax precipitation enthalpy of the crude oil sample at that wellbore location based on the wax precipitation point and the interpolation baseline of the wellbore temperature range. By combining the wax precipitation enthalpy with the organic solids blockage, it determines the wax content during the process from the bottom of the well to the wellbore, thereby obtaining the amount of organic solids deposition in crude oil at different wellbore locations.

[0023] The evaluation module assesses the impact of wellbore fouling on the deposition of organic solids in crude oil based on the amount of organic solids deposited at different wellbore locations.

[0024] As a further improvement of the present invention, the step of cooling down at a set rate according to the first temperature and recording the change of differential heat flow with respect to temperature in real time specifically includes: using a differential scanning calorimeter to control the temperature in the well location area to decrease at a set rate, and detecting the change of differential heat flow with respect to temperature at the well location.

[0025] As a further improvement of the present invention, the first temperature is the initial temperature at the wellbore location, and the second temperature is set to -30°C.

[0026] As a further improvement of the present invention, the step of determining the wax precipitation enthalpy of the crude oil sample at the wellbore location based on the interpolation baseline of the wax precipitation point and the wellbore temperature range includes: selecting the interpolation baseline from the wax precipitation point to the wellbore temperature range, and using the ratio of the peak area enclosed by the differential scanning calorimetry curve and the mass of the crude oil sample as the wax precipitation enthalpy of the crude oil sample.

[0027] As a further improvement of the present invention, the wax precipitation point is the intersection of the high-temperature exothermic baseline of the differential scanning calorimetry curve and the extension line of the first front line, and both the high-temperature exothermic baseline and the first front line deviate from the exothermic baseline.

[0028] As a further improvement of the present invention, the step of determining the wax content in the process from the bottom of the well to the wellbore by means of the wax precipitation enthalpy and the organic solid phase blockage includes: determining the wax content in the process from the bottom of the well to the wellbore by means of the ratio of the sample precipitation enthalpy to the crystallization heat of the organic solid phase blockage, and obtaining the amount of organic solid phase deposition in the crude oil.

[0029] As a further improvement of the present invention, the evaluation of the effect of wellbore fouling on the deposition of organic solid phase in crude oil based on the amount of organic solid phase deposition in crude oil at different wellbore locations includes: after obtaining the amount of organic solid phase deposition in crude oil at different wellbore locations, obtaining the wellbore fouling in crude oil at different wellbore locations, obtaining the wellbore fouling precipitation results at different temperatures using an orthogonal polarized light microscope, and determining the content and particle size of wellbore fouling at different temperatures based on the precipitation results;

[0030] The precipitation results of crude oil at different well locations under corresponding temperatures when there is no well fouling were obtained, and the corresponding amount of organic solid phase deposition was obtained based on the precipitation results;

[0031] The amount of organic solids deposited with wellbore fouling at different temperatures was compared with that without wellbore fouling, and the impact of wellbore fouling on the wax content of crude oil was evaluated based on the comparison results.

[0032] Thirdly, the present invention also provides an electronic device, including a processor and a memory, wherein the processor is used to execute a computer program stored in the memory to implement the evaluation method for the influence of wellbore fouling on organic solid phase deposition as described above.

[0033] Fourthly, the present invention also provides a computer-readable storage medium storing at least one instruction, which, when executed by a processor, implements the above-described method for evaluating the influence of wellbore fouling on organic solid phase deposition.

[0034] The beneficial effects of this invention are as follows: The evaluation method for the influence of wellbore fouling on organic solid phase deposition primarily considers the effect of temperature when evaluating the impact of wellbore fouling on organic solid phase deposition in crude oil. By determining the temperature field at different wellbore locations in a single well and setting a first temperature accordingly for cooling simulation, the actual temperature change process in the wellbore can be accurately simulated. This precise temperature control makes the study of wax precipitation characteristics closer to actual working conditions, improving the accuracy and reliability of the analysis results. Plotting differential scanning calorimetry (DSC) curves at different wellbore locations not only visually demonstrates the thermal effect changes of crude oil samples during the cooling process but also determines the interpolation baseline of the wax precipitation point and wellbore temperature range through curve analysis. This information is crucial for understanding the phase change behavior of crude oil, predicting wax precipitation trends, and developing anti-wax measures. Based on the wax precipitation enthalpy determined by the DSC curves, combined with the analysis of organic solid phase blockages, the wax content of crude oil during the process from the bottom of the well to the wellbore can be accurately estimated. By comprehensively considering the influence of wax precipitation enthalpy and wellbore fouling, the amount of organic solid phase deposition in crude oil at different wellbore locations can be comprehensively evaluated. This estimate provides direct guidance for assessing pipeline blockage risks, developing dewaxing plans, and optimizing mining processes. Attached Figure Description

[0035] To more clearly illustrate the technical solutions in the embodiments of the present invention 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 some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0036] Figure 1 This is a schematic diagram of the evaluation method for the influence of wellbore fouling on organic solid phase deposition in an embodiment of the present invention;

[0037] Figure 2 This is a schematic diagram of the structure of an evaluation system for the influence of wellbore fouling on organic solid phase deposition in an embodiment of the present invention;

[0038] Figure 3 This is a schematic diagram of the electronic device structure in an embodiment of the present invention. Detailed Implementation

[0039] To make the objectives and technical solutions of this invention clearer and easier to understand, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. The specific embodiments described herein are for illustrative purposes only and are not intended to limit the invention.

[0040] During production, formation fluids flow and migrate along the wellbore. With changes in temperature and pressure, inorganic scale solids continuously precipitate, resembling wax crystal nuclei. These nuclei, composed of inorganic scale solid particles, provide a basis for further aggregation of wax molecules. Once the nuclei are stable, as the temperature continues to decrease, the interaction between oil and wax molecules gradually weakens, while the attraction between wax molecules begins to dominate. At this point, wax molecules begin to aggregate and deposit on the nuclei, gradually forming wax crystals. These wax crystal nuclei are composed of interconnected resins, asphaltenes, and wax molecules, and their structure and properties significantly influence the wax precipitation process. The influence of wax crystal nuclei on wax precipitation is mainly reflected in their role as the starting point and foundation for wax molecule aggregation, determining the growth mode and properties of wax crystals, and thus affecting the wax precipitation process and physical properties of crude oil. The particle size and content of scale precipitated from formation water under different temperature and pressure conditions were tested using orthogonal polarized light microscopy. Since the effects of temperature on the precipitation of wax in crude oil or organic solid phases are generally greater than those of pressure, the influence of temperature is primarily considered when evaluating the impact of wellbore fouling on the deposition of organic solid phases in crude oil. Based on the above considerations, the present invention provides a method, system, equipment, and medium for evaluating the impact of wellbore fouling on the deposition of organic solid phases. The evaluation method mainly includes:

[0041] First, determine the temperature field corresponding to different wellbore locations in a single well, and set the first temperature according to the temperature field corresponding to different wellbore locations.

[0042] Secondly, the temperature is reduced at a set rate according to the first temperature, and the change of differential heat flow with temperature is recorded in real time until the second temperature is reached. Based on the recorded change of differential heat flow with temperature, differential scanning calorimetry curves at different well locations are plotted.

[0043] The first temperature is the initial temperature at the wellbore location, and the second temperature is set to -30℃.

[0044] Next, the wax precipitation point and the interpolation baseline of the wellbore temperature range are determined based on the differential scanning calorimetry curves at different wellbore locations. The wax precipitation enthalpy of the crude oil sample at that wellbore location is determined based on the wax precipitation point and the interpolation baseline of the wellbore temperature range. The wax content during the process from the bottom of the well to the wellbore is determined by the wax precipitation enthalpy and the organic solid phase blockage. Thus, the amount of organic solid phase deposition in the crude oil at different wellbore locations is obtained. The organic solid phase blockage includes organic solid phase and wellbore fouling.

[0045] The interpolation baseline from the wax precipitation point to the wellbore temperature range is selected, and the ratio of the peak area enclosed by the differential scanning calorimetry (DSC) curve to the crude oil sample mass is used as the wax precipitation enthalpy of the sample. The wax content during the process from the bottom of the well to the wellbore is determined by the ratio of the sample's precipitation enthalpy to the crystallization heat of the organic solid phase blockage, and the amount of organic solid phase deposition in the crude oil is obtained. The wax precipitation point is defined as the intersection of the high-temperature exothermic baseline of the DSC curve and the extension of the first front line; both the high-temperature exothermic baseline and the first front line deviate from the exothermic baseline.

[0046] Finally, the impact of wellbore fouling on the deposition of organic solids in crude oil was evaluated based on the amount of organic solids deposited in crude oil at different wellbore locations.

[0047] The process involves obtaining the amount of organic solids deposited in crude oil at different wellbore locations and comparing it with the precipitation results of crude oil without wellbore fouling at the corresponding wellbore locations. The impact of wellbore fouling on the deposition of organic solids in crude oil is evaluated based on the comparison results. Specifically, this includes: obtaining the amount of organic solids deposited in crude oil at different wellbore locations; acquiring wellbore fouling at different wellbore locations; obtaining wellbore fouling precipitation results at different temperatures using orthogonal polarized light microscopy; determining the content and particle size of wellbore fouling at different temperatures based on the precipitation results; obtaining the precipitation results of crude oil at different wellbore locations without wellbore fouling at corresponding temperatures; obtaining the corresponding amount of organic solids deposited based on the precipitation results; and comparing the amount of organic solids deposited with and without wellbore fouling at different temperatures to evaluate the impact of wellbore fouling on the wax content of crude oil.

[0048] The technical solution of the present invention will be clearly and completely described below with reference to the accompanying drawings and specific embodiments. The described embodiments are only some embodiments of the present invention, and not all embodiments.

[0049] Example 1

[0050] like Figure 1 As shown in the figure, this embodiment provides a method for evaluating the impact of wellbore fouling on organic solid phase deposition. The specific implementation method is as follows.

[0051] First, determine the temperature field corresponding to different wellbore locations within a single well, and then set a first temperature based on the temperature field at each wellbore location. Different first temperatures are set for different wellbore locations. The first temperature is generally the initial flow temperature or formation temperature at different locations within the wellbore.

[0052] Secondly, the temperature is lowered at a set rate based on the first temperature, and the change in differential heat flow with temperature is recorded in real time until the second temperature is reached. Based on the recorded change in differential heat flow with temperature, differential scanning calorimetry (DSC) curves are plotted at different wellbore locations. In this embodiment, the second temperature is set to -30℃. In this embodiment, the vertical axis of the differential scanning calorimetry curve represents differential heat flow, and the horizontal axis represents temperature.

[0053] In practical oil and gas production, wellhead temperatures in wells with organic solid phase blockage are generally above 0°C. Therefore, it is necessary to determine the wax precipitation point (by plotting two curves on the DSC curve where the deviation from the exothermic baseline begins; one curve represents the exothermic baseline at high temperatures, and the other represents the first peak line where the deviation from the exothermic baseline begins; the intersection of the extensions of the two curves is the wax precipitation point). The wax precipitation point and the interpolation baseline for the wellbore temperature range are determined based on the differential scanning calorimetry (DSC) curves at different wellbore locations. The wax precipitation enthalpy of the crude oil sample at that wellbore location is then determined based on the wax precipitation enthalpy and the organic solid phase blockage in the crude oil. The wax content from the bottom of the well to the wellbore is then determined using the wax precipitation enthalpy and the organic solid phase blockage in the crude oil, thus obtaining the amount of organic solid phase deposition in the crude oil at different wellbore locations. In this embodiment, the organic solid phase blockage includes both organic solid phase and wellbore fouling. The ratio of the peak area enclosed by the interpolation baseline from the wax precipitation point to the wellbore temperature range and the DSC curve to the crude oil sample mass is selected as the wax precipitation enthalpy of the sample. By using the ratio of the enthalpy of sample precipitation to the heat of crystallization of organic solid phase plugs, the wax content during the process from the bottom of the well to the wellbore is determined, and the amount of organic solid phase deposited in crude oil is obtained.

[0054] Finally, the impact of wellbore fouling on the deposition of organic solids in crude oil was evaluated by obtaining the amount of organic solids deposited in crude oil at different wellbore locations.

[0055] Specifically, after obtaining the amount of organic solid phase deposition in crude oil at different wellbore locations, the results are compared with the precipitation results of crude oil without wellbore fouling at the corresponding wellbore locations. This includes: obtaining the amount of organic solid phase deposition in crude oil at different wellbore locations, acquiring wellbore fouling in crude oil at different wellbore locations, acquiring wellbore fouling precipitation results at different temperatures using orthogonal polarized light microscopy, and determining the content and particle size of wellbore fouling at different temperatures based on the precipitation results.

[0056] The precipitation results of crude oil at different well locations under corresponding temperatures when there is no well fouling were obtained, and the corresponding amount of organic solid phase deposition was obtained based on the precipitation results;

[0057] The amount of organic solids deposited with wellbore fouling at different temperatures was compared with that without wellbore fouling, and the impact of wellbore fouling on the wax content of crude oil was evaluated based on the comparison results.

[0058] The evaluation method for the impact of wellbore fouling on organic solid phase deposition in this embodiment can be obtained through simulation modeling or actual experimental simulation.

[0059] When using a simulation model to simulate this method, the data used is based on data obtained from actual single wells. This includes data such as crude oil sample mass and the content of organic solids and wellbore fouling at different temperatures and pressures. The simulation process is implemented based on the above.

[0060] This embodiment further illustrates the effect of wellbore scaling on the deposition of organic solid phases in crude oil through experimental simulation. The main factor considered in evaluating the impact of temperature is the temperature. The experimental steps mainly include:

[0061] (1) Inject formation water into a pressure-resistant, visible reactor container and heat and pressurize it to the bottom of the well.

[0062] (2) Set the temperature and pressure values ​​according to the single-well flow temperature and pressure curve, and test the precipitation of scale in formation water under different temperature and pressure conditions by orthogonal polarized light microscopy. By analyzing the images tested by orthogonal polarized light microscopy, determine the particle size and content of scale. The content is determined by the ratio of the area occupied by scale in the image to the total area.

[0063] (3) Collect the scale sample precipitated from the formation water into a sample container for mixing with crude oil or organic blockages.

[0064] (4) The organic solid phase at a certain position from the bottom of the well to the wellhead or from the bottom of the well to the wellbore is tested by differential scanning calorimetry. First, the heat of crystallization of the organic solid phase is set to 190J / g to 200J / g to calibrate the enthalpy value of the organic solid phase per unit mass. This enthalpy value can be determined by differential scanning calorimetry.

[0065] (5) Select a certain amount of crude oil and scale mixture or organic solid phase blockage and scale mixture and place it in the crucible of the differential scanning calorimeter for cold welding; this step requires first selecting the wellbore location for simulating the effect of wellbore scaling on the deposition of organic solid phase in crude oil, and setting the temperature according to the temperature field at the wellbore location.

[0066] The test sample is prepared by mixing crude oil or organic plugging material with scale. The mixing ratio is determined by the water content of the fluid produced by the oil and gas well and the proportion of organic solid phase in the crude oil.

[0067] (6) Start the differential scanning calorimeter (DSC detector): Set the temperature program (including upper temperature limit, cooling rate, and final temperature), start the DSC detector, heat the DSC detection cell to the initial test temperature (the initial temperature is generally set to the bottom flow temperature or formation temperature), and stabilize for 1 to 5 minutes.

[0068] (7) Starting from the set temperature, the temperature is reduced at a certain rate until -30℃. The differential heat flow of the test sample changes with temperature. The differential scanning calorimetry (DSC) curve is plotted with differential heat flow as the vertical axis and temperature as the horizontal axis.

[0069] (8) Calculation of wax content: In view of the actual oil and gas production, for oil and gas wells with organic solid phase blockage, the wellhead temperature is generally higher than 0℃. Therefore, the wax precipitation point (two curves are drawn on the DSC curve where it begins to deviate from the heat release baseline, one is the heat release baseline at high temperature, and the other is the first peak line that begins to deviate from the heat release baseline. The intersection of the extension lines of the two curves is the wax precipitation point) is selected as the ratio of the peak area enclosed by the interpolation baseline and the DSC curve to the sample mass. The wax precipitation enthalpy of the test sample is determined by the ratio of the sample precipitation enthalpy to the crystallization heat of the organic solid phase blockage in the block.

[0070] (9) Change the wellbore position and take a point every 500m above the wax precipitation point. Prepare corresponding test samples according to the scale samples precipitated at different positions. Repeat steps (5) to (8) to obtain the amount of organic solid phase deposited in crude oil at each wellbore position.

[0071] (10) By comparing the test results of organic solid phase deposition in crude oil with the results of crude oil / organic solid phase precipitation without the addition of scale at different well locations, the influence of well scale on the deposition of organic solid phase in crude oil can be evaluated.

[0072] To address the shortcomings of existing technologies, this invention provides a method for evaluating the impact of wellbore scaling on the deposition of organic solid phases in crude oil. This method is based on the fact that during production, formation fluids flow and migrate along the wellbore. With changes in temperature and pressure, inorganic scale solids are continuously precipitated, resembling wax crystal nuclei. These nuclei are composed of inorganic scale solid particles, providing a basis for further aggregation of wax molecules. Once the nuclei are stable, as the temperature continues to decrease, the interaction between oil and wax molecules gradually weakens, while the attraction between wax molecules begins to dominate. At this point, wax molecules begin to aggregate and deposit on the nuclei, gradually forming wax crystals. These wax crystal nuclei are composed of interconnected colloids, asphaltenes, and wax molecules, and their structure and properties significantly influence the wax precipitation process. The influence of wax crystal nuclei on wax precipitation is mainly reflected in their role as the starting point and foundation for wax molecule aggregation, determining the growth mode and properties of wax crystals, and thus affecting the wax precipitation process and physical properties of crude oil. The particle size and content of scale precipitated from formation water under different temperature and pressure conditions were tested using orthogonal polarized light microscopy. This is because the precipitation of wax from crude oil or organic solid phases is generally more affected by temperature than by pressure.

[0073] Therefore, when evaluating the impact of wellbore scaling on the deposition of organic solids in crude oil, the effect of temperature is the primary consideration. Assuming the evaluation of the impact of scaling at a certain depth in the wellbore on the deposition of organic solids in crude oil, it is only necessary to test the effect of the particle size and content of the scale sample on the deposition of organic solids in crude oil under different temperature and pressure conditions. This method realistically simulates and evaluates the impact of scaling and scaling amount at different locations in the wellbore on the wax content of crude oil under different temperature and pressure conditions. By comprehensively considering the enthalpy of wax precipitation and the influence of wellbore fouling, the amount of organic solids deposited in crude oil at different wellbore locations can be comprehensively assessed. This comprehensive assessment helps to reveal the mechanism by which wellbore fouling affects crude oil fluidity and provides a scientific basis for taking effective scale prevention measures. Through precise temperature control and heat flow analysis, an in-depth study of the wax precipitation characteristics of crude oil at different wellbore locations in a single well was achieved, and the impact of wellbore fouling on the deposition of organic solids in crude oil was evaluated accordingly. The application of this method is of great significance for improving oil extraction efficiency, ensuring production safety, and promoting technological innovation and development. It also plays an important role in enhancing the understanding of crude oil wax precipitation in oilfields.

[0074] Example 2

[0075] like Figure 2 This embodiment provides an evaluation system for the impact of wellbore fouling on organic solid phase deposition, used to implement the evaluation method for the impact of wellbore fouling on organic solid phase deposition in Embodiment 1. The system includes:

[0076] The wellbore temperature setting module is used to determine the temperature field corresponding to different wellbore locations in a single well, and set the first temperature according to the temperature field corresponding to different wellbore locations.

[0077] The data simulation module is used to cool down at a set rate according to the first temperature, record the changes in temperature with respect to differential heat flow in real time until the second temperature is reached, and plot the differential scanning calorimetry curves at different well locations based on the recorded changes in temperature with respect to differential heat flow.

[0078] The first temperature is the initial temperature at different wellbore locations, and the second temperature is set to -30℃.

[0079] The organic solids deposition calculation module determines the wax precipitation point and the interpolation baseline of the wellbore temperature range based on the differential scanning calorimetry curves at different wellbore locations. It then determines the wax precipitation enthalpy of the crude oil sample at that wellbore location based on the wax precipitation point and the interpolation baseline of the wellbore temperature range. By comparing the wax precipitation enthalpy with the organic solids blockage, it determines the wax content during the process from the bottom of the well to the wellbore, and thus obtains the amount of organic solids deposition in crude oil at different wellbore locations.

[0080] Specifically, the interpolation baseline from the wax precipitation point to the wellbore temperature range is selected, and the ratio of the peak area enclosed by the differential scanning calorimetry (DSC) curve to the crude oil sample mass is used as the wax precipitation enthalpy of the sample. The wax precipitation point is the intersection of the high-temperature exothermic baseline of the DSC curve and the extension of the first front line, both of which deviate from the exothermic baseline.

[0081] By using the ratio of the enthalpy of sample precipitation to the heat of crystallization of organic solid phase plugs, the wax content during the process from the bottom of the well to the wellbore is determined, and the amount of organic solid phase deposited in crude oil is obtained.

[0082] The evaluation module assesses the impact of wellbore fouling on the deposition of organic solids in crude oil based on the amount of organic solids deposited at different wellbore locations.

[0083] Specifically, after obtaining the amount of organic solid phase deposition in crude oil at different well locations, well fouling in crude oil at different well locations is obtained. Well fouling precipitation results at different temperatures are obtained using orthogonal polarized light microscopy. Based on the precipitation results, the content and particle size of well fouling at different temperatures are determined.

[0084] The precipitation results of crude oil at different well locations under corresponding temperatures when there is no well fouling were obtained, and the corresponding amount of organic solid phase deposition was obtained based on the precipitation results;

[0085] The amount of organic solids deposited with wellbore fouling at different temperatures was compared with that without wellbore fouling, and the impact of wellbore fouling on the wax content of crude oil was evaluated based on the comparison results.

[0086] Example 3

[0087] like Figure 3The embodiment shown provides an electronic device for implementing the evaluation method for the influence of wellbore fouling on organic solid phase deposition in Embodiment 1. The electronic device 100 includes at least one processor 102, a memory 101, a computer program 103 stored in the memory 101 and executable on at least one processor 102, and at least one communication bus 104. The memory 101 can be used to store the computer program 103. The processor 102 implements the steps of the evaluation method for the influence of wellbore fouling on organic solid phase deposition in Embodiment 1 by running or executing the computer program stored in the memory 101 and calling data stored in the memory 101. The memory 101 may mainly include a program storage area and a data storage area. The program storage area may store the operating system, at least one application program required for a function (such as sound playback function, image playback function, etc.), etc.; the data storage area may store data created based on the use of the electronic device 100 (such as audio data), etc. In addition, memory 101 may include non-volatile memory, such as hard disk, memory, plug-in hard disk, smart media card (SMC), secure digital (SD) card, flash card, at least one disk storage device, flash memory device, or other non-volatile solid-state storage device.

[0088] At least one processor 102 may be a Central Processing Unit (CPU), or 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, etc. Processor 102 may be a microprocessor or any conventional processor. Processor 102 is the control center of electronic device 100, connecting various parts of electronic device 100 via various interfaces and lines.

[0089] The memory 101 in the electronic device 100 stores multiple instructions to implement a method for evaluating the impact of wellbore fouling on organic solid phase deposition, and the processor 102 can execute multiple instructions to achieve the following:

[0090] Determine the temperature field corresponding to different wellbore locations in a single well, and set the first temperature according to the temperature field corresponding to different wellbore locations;

[0091] The temperature is reduced at a set rate based on the first temperature, and the change of differential heat flow with temperature is recorded in real time until the second temperature is reached. Based on the recorded change of differential heat flow with temperature, differential scanning calorimetry curves are plotted at different well locations.

[0092] The wax precipitation point and the interpolation baseline of the wellbore temperature range are determined based on the differential scanning calorimetry curves at different wellbore locations. The wax precipitation enthalpy of the crude oil sample at that wellbore location is determined based on the wax precipitation point and the interpolation baseline of the wellbore temperature range. The wax content during the process from the bottom of the well to the wellbore is determined by the wax precipitation enthalpy and the organic solid phase blockage. The amount of organic solid phase deposition in the crude oil at different wellbore locations is then obtained. The organic solid phase blockage includes organic solid phase and wellbore fouling.

[0093] The impact of wellbore fouling on the deposition of organic solids in crude oil was evaluated based on the amount of organic solids deposited at different wellbore locations.

[0094] Example 4

[0095] If the modules / units integrated in the electronic device 100 are implemented as software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, all or part of the processes in the methods of the above embodiments of the present invention can also be implemented by a computer program instructing related hardware. The computer program can be stored in a computer-readable storage medium, and when executed by a processor, it can implement the steps of the various method embodiments described above. The computer program includes computer program code, which can be in the form of source code, object code, executable files, or certain intermediate forms. The computer-readable medium can include: any entity or device capable of carrying computer program code, recording media, USB flash drives, portable hard drives, magnetic disks, optical disks, computer memory, and read-only memory (ROM).

[0096] This invention is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart illustrations and / or block diagrams. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0097] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0098] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the specific implementation of the present invention. Any modifications or equivalent substitutions that do not depart from the spirit and scope of the present invention should be covered within the scope of protection of the claims of the present invention.

Claims

1. A method for evaluating the influence of wellbore fouling on organic solid phase deposition, characterized in that, include: Determine the temperature field corresponding to different wellbore locations in a single well, and set the first temperature according to the temperature field corresponding to different wellbore locations; The temperature is reduced at a set rate based on the first temperature, and the change of differential heat flow with temperature is recorded in real time until the second temperature is reached. Based on the recorded change of differential heat flow with temperature, differential scanning calorimetry curves are plotted at different well locations. The wax precipitation point and the interpolation baseline of the wellbore temperature range are determined based on the differential scanning calorimetry curves at different wellbore locations. The wax precipitation enthalpy of the crude oil sample at that wellbore location is determined based on the wax precipitation point and the interpolation baseline of the wellbore temperature range. The wax content during the process from the bottom of the well to the wellbore is determined by the wax precipitation enthalpy and the organic solid phase blockage. The amount of organic solid phase deposition in the crude oil at different wellbore locations is then obtained. The organic solid phase blockage includes organic solid phase and wellbore fouling. The impact of wellbore fouling on the deposition of organic solids in crude oil was evaluated based on the amount of organic solids deposited at different wellbore locations.

2. The evaluation method for the influence of wellbore fouling on organic solid phase deposition according to claim 1, characterized in that, The step of cooling down at a set rate based on a first temperature and recording the temperature change of differential heat flow in real time specifically includes: using a differential scanning calorimeter to control the temperature in the well location area to decrease at a set rate, and detecting the temperature change of differential heat flow at that well location.

3. The evaluation method for the influence of wellbore fouling on organic solid phase deposition according to claim 1, characterized in that, The first temperature is the initial temperature at this wellbore location, and the second temperature is set to -30℃.

4. The evaluation method for the influence of wellbore fouling on organic solid phase deposition according to claim 1, characterized in that, The step of determining the wax precipitation enthalpy of the crude oil sample at the wellbore location based on the interpolation baseline between the wax precipitation point and the wellbore temperature range includes: selecting the interpolation baseline from the wax precipitation point to the wellbore temperature range, and using the ratio of the peak area enclosed by the differential scanning calorimetry curve and the mass of the crude oil sample as the wax precipitation enthalpy of the crude oil sample.

5. The evaluation method for the influence of wellbore fouling on organic solid phase deposition according to claim 4, characterized in that, The wax precipitation point is the intersection of the high-temperature exothermic baseline of the differential scanning calorimetry curve and the extension of the first front line. Both the high-temperature exothermic baseline and the first front line deviate from the exothermic baseline.

6. The evaluation method for the influence of wellbore fouling on organic solid phase deposition according to claim 1, characterized in that, The method of determining the wax content in the process from the bottom of the well to the wellbore by means of the wax precipitation enthalpy and the organic solid phase blockage includes: determining the wax content in the process from the bottom of the well to the wellbore by means of the ratio of the sample precipitation enthalpy to the crystallization heat of the organic solid phase blockage, and obtaining the amount of organic solid phase deposition in the crude oil.

7. The evaluation method for the influence of wellbore fouling on organic solid phase deposition according to claim 1, characterized in that, The method of evaluating the effect of wellbore fouling on the deposition of organic solid phases in crude oil based on the amount of organic solid phases deposited in crude oil at different wellbore locations includes: obtaining the amount of organic solid phases deposited in crude oil at different wellbore locations, obtaining the wellbore fouling in crude oil at different wellbore locations, obtaining the wellbore fouling precipitation results at different temperatures using orthogonal polarized light microscopy, and determining the content and particle size of wellbore fouling at different temperatures based on the precipitation results. The precipitation results of crude oil at different well locations under corresponding temperatures when there is no well fouling were obtained, and the corresponding amount of organic solid phase deposition was obtained based on the precipitation results; The amount of organic solids deposited with wellbore fouling at different temperatures was compared with that without wellbore fouling, and the impact of wellbore fouling on the wax content of crude oil was evaluated based on the comparison results.

8. An evaluation system for the influence of wellbore fouling on organic solid phase deposition, characterized in that, include: The wellbore temperature setting module is used to determine the temperature field corresponding to different wellbore locations in a single well, and set the first temperature according to the temperature field corresponding to different wellbore locations. The data simulation module is used to cool down at a set rate according to the first temperature, record the changes in temperature with respect to differential heat flow in real time until the second temperature is reached, and plot the differential scanning calorimetry curves at different well locations based on the recorded changes in temperature with respect to differential heat flow. The organic solids deposition calculation module determines the wax precipitation point and the interpolation baseline of the wellbore temperature range based on the differential scanning calorimetry curves at different wellbore locations. It then determines the wax precipitation enthalpy of the crude oil sample at that wellbore location based on the wax precipitation point and the interpolation baseline of the wellbore temperature range. By combining the wax precipitation enthalpy with the organic solids blockage, it determines the wax content during the process from the bottom of the well to the wellbore, thereby obtaining the amount of organic solids deposition in crude oil at different wellbore locations. The evaluation module assesses the impact of wellbore fouling on the deposition of organic solids in crude oil based on the amount of organic solids deposited at different wellbore locations.

9. An electronic device, characterized in that, It includes a processor and a memory, the processor being used to execute a computer program stored in the memory to implement the evaluation method for the influence of wellbore fouling on organic solid phase deposition as described in any one of claims 1-7.

10. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores at least one instruction, which, when executed by a processor, implements the evaluation method for the influence of wellbore fouling on organic solid phase deposition as described in any one of claims 1-7.

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