Solid paraffin inhibitor process method and device for high-pressure condensate gas well

Abstract

The invention belongs to the technical field of oil and gas production engineering, and discloses a solid paraffin inhibitor process method and device for a high-pressure condensate gas well, and the process method comprises the steps that the setting depth of a solid paraffin inhibitor shaft bearing device is determined according to the paraffin precipitation depth of a shaft of the high-pressure condensate gas well; drifting operation is conducted, and a shaft bearing device is tripped in according to the tripping-in depth; installing and connecting a wellhead injection device at the upper part of the wellhead gas production tree and injecting a solid paraffin inhibitor; carrying out field test tracking, observing the well mouth leakage condition and the shaft / well mouth blockage condition, and evaluating the paraffin control effect and the validity period; and the filling period and the single-time adding amount of the solid paraffin inhibitor are adjusted according to the field test tracking result. By optimizing the solid paraffin inhibitor process method, the solid paraffin inhibitor is suitable for the high-pressure condensate gas well, and the production requirement for long-term paraffin inhibition of the high-pressure condensate gas well can be met.

Description

Technical Field

[0001] The invention belongs to the technical field of oil and gas production engineering, and in particular relates to a solid wax inhibitor process method and device for high-pressure condensate gas wells. Background Art

[0002] During the oil and gas production process in the oil field, the temperature, pressure and composition of the fluid system change, changing the original thermodynamic equilibrium conditions of the fluid system, resulting in the conversion of the three phases of gas, liquid and solid. The wax deposition in high-pressure condensate gas wells is divided into three stages: wax precipitation stage, wax crystal growth stage and deposition stage. The main reason for wax deposition in high-pressure condensate gas wells is that the gas wells produce condensate oil with high wax content while producing gas. If the shear strength of the precipitated paraffin exceeds the shear stress acting on it, it will form a flow barrier, causing blockage or deposition. Once the wellbore of a high-pressure condensate gas well is blocked by wax deposition, it will lead to great difficulties in safe production and seriously affect the stable supply of natural gas.

[0003] High-pressure condensate gas wells can be paraffin-proofed by solid paraffin inhibitors, but current research on solid paraffin inhibitors mainly focuses on the evaluation of the paraffin-proofing effect of solid paraffin inhibitors and the injection of solid paraffin inhibitors into the annulus of oil wells. Since the existing solid paraffin inhibitor technology is mainly concentrated in oil wells, there is no solid paraffin inhibitor technology method for high-pressure condensate gas wells, which cannot meet the long-term paraffin-proofing production needs of high-pressure condensate gas wells. Summary of the invention

[0004] In order to overcome the defects of the above-mentioned prior art, the purpose of the present invention is to provide a solid wax inhibitor process method and device for high-pressure condensate gas wells to meet the production needs of long-term wax prevention in high-pressure condensate gas wells.

[0005] To achieve the above object, the present invention provides the following technical solutions:

[0006] A solid paraffin inhibitor process for high-pressure condensate gas wells, comprising:

[0007] Determine the depth of the solid wax inhibitor receiving device in the wellbore according to the wax precipitation depth of the high-pressure condensate gas well;

[0008] Carry out well-drilling operation and lower the wellbore receiving device according to the lowering depth;

[0009] Install a wellhead injection device on the upper part of the wellhead gas tree and inject solid wax inhibitor into the wellbore receiving device;

[0010] Conduct field test tracking, observe wellhead leakage and wellbore / wellhead blockage, and evaluate the anti-wax effect and validity period;

[0011] Adjust the solid wax inhibitor filling cycle and single addition amount according to the field test tracking results.

[0012] Furthermore, before judging the wellbore blockage and wax precipitation depth of the high-pressure condensate gas well, the following steps are included:

[0013] Determine whether the wellbore / wellhead is blocked based on the on-site production situation of the high-pressure condensate gas well;

[0014] The depth of wellbore blockage is determined based on previous well cleaning operations or continuous tubing dredging operations, thereby determining the depth of wax precipitation.

[0015] Furthermore, when there is no previous well cleaning operation or continuous tubing dredging operation, the wax precipitation depth is simulated using phase prediction software based on the PVT analysis data of the high-pressure condensate gas well or the oil and gas component analysis data.

[0016] Furthermore, the wax precipitation depth is 50-500m.

[0017] Furthermore, the well-drilling operation is carried out and a receiving device is lowered into the wellbore according to the lowering depth, including:

[0018] The immersion depth should not be less than the wax precipitation depth.

[0019] Furthermore, when the wellbore receiving device is multi-level, the wellbore receiving device at the bottom layer can be lowered to the bottom of the wellbore or the depth of the production layer.

[0020] Furthermore, the wellbore receiving device is of level 2-3, the wellbore receiving device is clamped with the inner wall of the oil pipe through a slip, and the slip is released by lifting the wellbore receiving device.

[0021] Furthermore, well cleaning operations include well cleaning by “wireline operation + well cleaning rules” or well cleaning by continuous tubing cleaning operations.

[0022] Furthermore, a wellhead injection device is installed on the upper part of the wellhead gas tree and a solid wax inhibitor is injected into the wellbore receiving device, including:

[0023] Step 1: Install the wellhead injection device on the top of the wellhead gas tree and test the pressure;

[0024] Step 2: Close the blind plug and manual gate valve of the wellhead injection device after the pressure test is qualified;

[0025] Step 3: Open the blind plug of the wellhead injection device to release the gas pressure in the wellhead injection device to zero;

[0026] Step 4: After the pressure is released, put the solid wax inhibitor from the blind plug into the wellhead injection device, then close the blind plug and open the manual gate valve to allow the solid wax inhibitor to fall to the wellbore receiving device;

[0027] Step 5: Repeat steps 2 to 4 until the amount of solid wax inhibitor injection reaches the preset amount;

[0028] Step 6: Close the blind plug and manual gate valve.

[0029] Furthermore, the wellhead injection device is a tubular structure with blind plugs and manual gate valves at both ends, and the end close to the manual gate valve is installed and connected to the upper part of the wellhead gas production tree.

[0030] Furthermore, field test tracking is conducted to observe wellhead leakage and wellbore / wellhead blockage, and to evaluate the anti-wax effect and validity period, including:

[0031] Track production, casing pressure and wellhead temperature in real time, regularly observe whether there is leakage at the wellhead, and determine whether the wellbore / wellhead is blocked based on on-site production conditions;

[0032] Oil samples are taken regularly before drainage and after production stabilizes, and the condensate point is measured before and after the injection of solid wax inhibitor to evaluate the wax inhibitor effect and validity period.

[0033] On the other hand, the present invention discloses a solid wax inhibitor device for high-pressure condensate gas wells, comprising:

[0034] A lowering depth determination module is used to determine the lowering depth of the solid wax inhibitor wellbore receiving device according to the wax precipitation depth of the high-pressure condensate gas wellbore;

[0035] A wellbore receiving device lowering module is used to carry out well-clearing operations and lower the wellbore receiving device according to the lowering depth;

[0036] The solid wax inhibitor injection module is used to install and connect the wellhead injection device on the upper part of the wellhead gas tree and inject the solid wax inhibitor into the wellbore receiving device;

[0037] Field test tracking module, used to track field tests, observe wellhead leakage and wellbore / wellhead blockage, and evaluate the anti-wax effect and validity period;

[0038] The filling cycle and single addition amount adjustment module is used to adjust the filling cycle and single addition amount of the solid wax inhibitor according to the field test tracking results.

[0039] Technical effects and advantages of the present invention:

[0040] The present invention first determines the wellbore blockage and wax precipitation depth of the high-pressure condensate gas well, and determines the depth of the solid wax inhibitor wellbore receiving device according to the wax precipitation depth of the wellbore, thereby improving the wax prevention effect;

[0041] The wellbore receiving device of the present invention is connected to the inner wall of the wellbore through a cava, and the cava is released by lifting the wellbore receiving device, so that the wellbore receiving device can be fished out conveniently;

[0042] The method of the present invention can be lowered into a multi-stage wellbore receiving device to achieve the anti-wax effect of deep fluid and reduce the anti-wax pressure of the upper wellbore;

[0043] The method of the present invention tracks data such as production, casing pressure and wellhead temperature in real time, determines whether the wellbore / wellhead is blocked according to the on-site production situation, takes oil samples at a certain time before drainage, and continues to take oil samples after the production stabilizes. The oil samples are used to measure parameters such as the freezing point of condensate oil before and after adding drugs, evaluates the anti-wax effect and validity period, and the injection cycle can be adjusted on-site according to the production and experimental analysis conditions, thereby achieving long-term wax prevention of high-pressure condensate gas wells and ensuring stable production of gas wells.

[0044] Other features and advantages of the present invention will be described in the following description, and partly become apparent from the description, or understood by practicing the present invention. The purpose and other advantages of the present invention can be realized and obtained by the structures pointed out in the description, claims and drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] Figure 1 This is a flow chart of a solid wax inhibitor process for high-pressure condensate gas wells according to the present invention;

[0046] Figure 2 This is the wellbore temperature distribution diagram at different production rates of Well A in Example 1. DETAILED DESCRIPTION

[0047] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0048] like Figure 1 As shown, the present invention provides a solid paraffin inhibitor process for high-pressure condensate gas wells, comprising:

[0049] Determine the depth of the solid wax inhibitor receiving device in the wellbore according to the wax precipitation depth of the high-pressure condensate gas well;

[0050] Carry out well-drilling operation and lower the wellbore receiving device according to the lowering depth;

[0051] Install a wellhead injection device on the upper part of the wellhead gas tree and inject solid wax inhibitor into the wellbore receiving device;

[0052] Conduct field test tracking, observe wellhead leakage and wellbore / wellhead blockage, and evaluate the anti-wax effect and validity period;

[0053] Adjust the solid wax inhibitor filling cycle and single addition amount according to the field test tracking results.

[0054] In some embodiments of the present invention, determining the wellbore blockage and wax precipitation depth of a high-pressure condensate gas well includes:

[0055] Determine whether the wellbore / wellhead is blocked based on the on-site production situation of the high-pressure condensate gas well;

[0056] The depth of wellbore blockage is determined based on previous well cleaning operations or continuous tubing dredging operations, thereby determining the depth of wax precipitation.

[0057] In some embodiments of the present invention, when there is no previous well cleaning operation or coiled tubing dredging operation, the wax precipitation depth is simulated using phase prediction software based on the PVT analysis data or oil and gas component analysis data of the high-pressure condensate gas well.

[0058] In some embodiments of the present invention, the wax precipitation depth is 50-500m.

[0059] In some embodiments of the present invention, when performing well-clearing operations and lowering a wellbore receiving device according to the lowering depth, the lowering depth is not less than the wax precipitation depth.

[0060] In some embodiments of the present invention, when the wellbore receiving device is multi-level, the wellbore receiving device at the bottom layer can be lowered to the bottom of the wellbore or the depth of the production layer.

[0061] In some embodiments of the present invention, the wellbore receiving device is of 2-3 levels. According to the designed depth, the deepest wellbore receiving device is lowered first, and then the shallower wellbore receiving devices are lowered in sequence to realize the anti-wax effect of the deep fluid and reduce the anti-wax pressure of the upper wellbore. The wellbore receiving device is clamped with the inner wall of the oil pipe through the cava, and the cava is released by lifting the wellbore receiving device.

[0062] It should be noted that the wellbore receiving device adopts a sitting and hanging wellbore receiving device, and the placement process includes: using the tool string to lower the wellbore receiving device to the designed depth, and after testing for abnormalities, quickly lifting and lowering the tool string so that the cava of the wellbore receiving device opens and gets stuck on the inner wall of the wellbore, and after judging that the wellbore receiving device is successfully placed, it is released and the tool string is pulled out.

[0063] In some embodiments of the present invention, the well cleaning operation includes "wireline operation + well cleaning gauge" well cleaning or continuous tubing dredging operation well cleaning.

[0064] In some embodiments of the present invention, a wellhead injection device is installed on the upper part of the wellhead gas tree and a solid wax inhibitor is injected into the wellbore receiving device, including:

[0065] Step 1: Install the wellhead injection device on the top of the wellhead gas tree and test the pressure to ensure that the pressure meets the preset standard;

[0066] Step 2: Close the blind plug and manual gate valve of the wellhead injection device after the pressure test is qualified;

[0067] Step 3: Open the blind plug of the wellhead injection device to release the gas pressure in the wellhead injection device to zero;

[0068] Step 4: After the pressure is released, put the solid wax inhibitor from the blind plug into the wellhead injection device, then close the blind plug and open the manual gate valve to allow the solid wax inhibitor to fall to the wellbore receiving device;

[0069] Step 5: Repeat steps 2 to 4 until the amount of solid wax inhibitor injection reaches the preset amount;

[0070] Step 6: Close the blind plug and manual gate valve.

[0071] In some embodiments of the present invention, the wellhead injection device is a tubular structure with blind plugs and manual gate valves at both ends, and the end close to the manual gate valve is installed and connected to the upper part of the wellhead gas production tree.

[0072] In some embodiments of the present invention, field test tracking is performed to observe wellhead leakage and wellbore / wellhead blockage, and to evaluate the anti-wax effect and validity period, including:

[0073] Track production, casing pressure and wellhead temperature in real time, regularly observe whether there is leakage at the wellhead, and determine whether the wellbore / wellhead is blocked based on on-site production conditions;

[0074] Oil samples are taken regularly before drainage and after production stabilizes, and the condensate point is measured before and after the injection of solid wax inhibitor to evaluate the wax inhibitor effect and validity period.

[0075] It should be noted that solid wax inhibitors have an effective period and need to be added regularly and at the right time according to production conditions. Before each addition, the well should be cleared to ensure that the wellbore is unobstructed before adding the agent.

[0076] On the other hand, the present invention discloses a solid wax inhibitor device for high-pressure condensate gas wells, comprising:

[0077] A lowering depth determination module is used to determine the lowering depth of the solid wax inhibitor wellbore receiving device according to the wax precipitation depth of the high-pressure condensate gas wellbore;

[0078] A wellbore receiving device lowering module is used to carry out well-clearing operations and lower the wellbore receiving device according to the lowering depth;

[0079] The solid wax inhibitor injection module is used to install and connect the wellhead injection device on the upper part of the wellhead gas tree and inject the solid wax inhibitor into the wellbore receiving device;

[0080] Field test tracking module, used to track field tests, observe wellhead leakage and wellbore / wellhead blockage, and evaluate the anti-wax effect and validity period;

[0081] The filling cycle and single addition amount adjustment module is used to adjust the filling cycle and single addition amount of the solid wax inhibitor according to the field test tracking results.

[0082] In order to better illustrate the present solution, the following embodiments are also provided.

[0083] Example 1

[0084] Well A is a high-pressure condensate gas well in an oil field in the west of China. It was put into production on May 9, 2020. In the early stage, it was produced with an 8mm nozzle, an oil pressure of 20MPa, a daily gas production of 120,000 cubic meters, and a daily oil production of 20 tons. Due to the low wellhead temperature and wax precipitation in the wellbore, the production oil pressure fluctuated and decreased. Figure 2 As shown, based on the PVT data of Well A, the highest wax precipitation temperature of the well is 38°C through software simulation. The current formation pressure is 95MPa, and the formation temperature is 120°C. By simulating the wellbore temperature distribution under daily production of 50,000 cubic meters, 100,000 cubic meters, and 150,000 cubic meters, the wellhead temperature is 13-20°C, and the initial wax precipitation depth in the wellbore is 1200-1600m.

[0085] S1: Determine the wellbore blockage and wax precipitation depth of high-pressure condensate gas wells.

[0086] Based on the on-site production situation of high-pressure condensate gas well A, it is determined that the wellbore is blocked;

[0087] Based on the PVT analysis data of high-pressure condensate gas wells or oil and gas component analysis data, the wax precipitation depth is simulated using phase prediction software and determined to be 1200-1600m.

[0088] S2: Determine the depth of the wellbore receiving device according to the wax precipitation depth. The depth should not be lower than the wax precipitation depth. The wellbore wax precipitation depth is selected to be 400m deep, that is, 2000m. If a first-level wellbore receiving device is lowered, the receiving position is 2000m in the wellbore.

[0089] S3: The depth of the wellbore receiving device is as deep as 3000m to ensure that the oil pipe is unobstructed, which is conducive to the subsequent lowering of the wellbore receiving device. The wellbore receiving device is cleared by "wire operation + wellbore receiving device" and the pressure test is qualified as required;

[0090] After the well is cleared, on the premise of ensuring that the wellbore receiving device is unobstructed, the wellbore receiving device is lowered to the designed depth of 2000m. After testing without abnormality, the tool string is quickly lifted and lowered so that the slip opens and gets stuck on the inner wall of the wellbore. After judging that the wellbore receiving device is successfully placed, the tool string is removed by letting go.

[0091] S4: Install the wellhead injection device on the upper part of the wellhead gas tree and inject the solid wax inhibitor into the wellbore receiving device.

[0092] (1) Install the wellhead injection device on the top of the wellhead gas tree and pass the pressure test;

[0093] (2) Close the blind plug and manual gate valve of the wellhead injection device;

[0094] (3) Slowly open the blind plug on the top of the wellhead injection device to release the gas pressure in the wellhead injection device to zero;

[0095] (4) When placing the solid wax inhibitor, first open the wellhead blind plug, put the solid wax inhibitor into the wellhead injection device, close the blind plug at the top of the wellhead injection device, open the manual gate valve at the bottom of the wellhead injection device, and the solid wax inhibitor falls to the receiving device in the wellbore under the action of gravity;

[0096] (5) Repeat steps (2)-(4) until the amount of solid wax inhibitor injection meets the design requirements. The total injection amount this time is 30m, each solid wax inhibitor is 0.5m, a total of 60 pieces, a total of 50kg;

[0097] (6) Close the blind plug and manual gate valve of the wellhead injection device.

[0098] S5: Conduct field test tracking, observe wellhead leakage and wellbore / wellhead blockage, and evaluate the anti-wax effect and validity period.

[0099] Real-time tracking of production, casing pressure, wellhead temperature and other data, observation of wellhead leakage every half hour, and determination of whether the wellbore / wellhead is blocked based on on-site production conditions;

[0100] Oil samples were taken every 2 hours in the early stage of drainage, and every 1-2 days after the production stabilized. The condensate point was measured before and after the injection of solid wax inhibitor to evaluate the wax inhibitor effect and validity period.

[0101] S6: Solid paraffin inhibitor has an effective period. The filling cycle is adjusted according to production and experimental analysis. The filling cycle of this well is 15 days, and the single addition amount is 50kg. Before the next injection, the well should be cleared to ensure that the wellbore is unobstructed before injection.

[0102] Example 2

[0103] Well B is a high-pressure condensate gas well in an oil field in the west of China. It was put into production on March 7, 2020. In the early stage, it was produced with an 8mm+20% oil nozzle system, an oil pressure of 20MPa, a daily gas production of 120,000 cubic meters, and a daily oil production of 20 tons. On October 23, 2020, the well was shut down due to wellbore blockage.

[0104] Continuous tubing dredging of Well B: obstructions were shown at 320m, 915m, 994m and 1314m in the wellbore, obvious obstruction was found at 1237m-1549m, and obstruction was shown at 1752m and 1912m.

[0105] S1: Determine the wellbore blockage and wax precipitation depth of high-pressure condensate gas wells.

[0106] Based on the on-site production situation of high-pressure condensate gas well B, it was determined that the wellbore was blocked;

[0107] The depth of wellbore blockage was determined based on the previous continuous tubing dredging operation, and thus the maximum wax precipitation depth was determined to be 1912m.

[0108] S2: Determine the depth of the wellbore receiving device according to the wax precipitation depth. The depth should not be lower than the wax precipitation depth. The wellbore wax precipitation depth is selected to be 300m deep, that is, 2300m. The wellbore is seriously blocked during the production process of the well. The second-level wellbore receiving device is lowered to the depths of 4000m and 2300m respectively.

[0109] S3: The depth of the wellbore receiving device is as deep as 5000m to ensure that the oil pipe is unobstructed, which is conducive to the subsequent lowering of the wellbore receiving device. The wellbore receiving device is cleared by "wire operation + wellbore receiving device" and the pressure test is qualified as required;

[0110] S4: After the well is cleared, on the premise of ensuring that the wellbore receiving device is unobstructed, the wellbore receiving device is lowered in two stages and first lowered to the designed depth of 4000m. After testing and finding no abnormalities, the tool string is quickly lifted up and lowered so that the slip opens and gets stuck on the inner wall of the wellbore. After judging that the wellbore receiving device is successfully placed, the tool string is removed by letting go.

[0111] S5: Install a wellhead injection device connected to the wellhead gas tree on the top and inject solid wax inhibitor to the wellbore receiving device at a depth of 4000m.

[0112] (1) Install the wellhead injection device on the top of the wellhead gas tree and pass the pressure test;

[0113] (2) Close the blind plug and manual gate valve of the wellhead injection device;

[0114] (3) Slowly open the blind plug on the top of the wellhead injection device to release the gas pressure in the wellhead injection device to zero;

[0115] (4) When placing the solid wax inhibitor, first open the wellhead blind plug, put the solid wax inhibitor into the wellhead injection device, close the blind plug at the top of the wellhead injection device, open the manual gate valve at the bottom of the wellhead injection device, and the solid wax inhibitor falls to the receiving device in the wellbore under the action of gravity;

[0116] (5) Repeat steps (2)-(4) until the amount of solid wax inhibitor injection meets the design requirements. The total injection amount this time is 60m, each solid wax inhibitor is 0.5m, a total of 120 pieces, a total of 100kg;

[0117] (6) Close the blind plug and manual gate valve of the wellhead injection device.

[0118] S6: After the first injection of solid wax inhibitor, under the premise of ensuring that the wellbore receiving device is unobstructed, the second-level wellbore receiving device is hung and lowered to the designed depth of 2300m. After testing without abnormality, the tool string is quickly lifted and lowered so that the hanger slip opens and gets stuck on the pipe wall. After judging that the hanger is successfully deployed, it is released and the tool string is pulled out.

[0119] S7: Install a wellhead injection device connected to the wellhead gas tree on the top and inject solid wax inhibitor to the wellbore receiving device at a depth of 4000m.

[0120] (1) Install the wellhead injection device on the top of the wellhead gas tree and pass the pressure test;

[0121] (2) Close the blind plug and manual gate valve of the wellhead injection device;

[0122] (3) Slowly open the blind plug on the top of the wellhead injection device to release the gas pressure in the wellhead injection device to zero;

[0123] (4) When placing the solid wax inhibitor, first open the wellhead blind plug, put the solid wax inhibitor into the wellhead injection device, close the blind plug at the top of the wellhead injection device, open the manual gate valve at the bottom of the wellhead injection device, and the solid wax inhibitor falls to the receiving device in the wellbore under the action of gravity;

[0124] (5) Repeat steps (2)-(4) until the amount of solid wax inhibitor injection meets the design requirements. The total injection amount this time is 30m, each solid wax inhibitor is 0.5m, a total of 60 pieces, a total of 50kg;

[0125] (6) Close the blind plug and manual gate valve of the wellhead injection device.

[0126] S8: Conduct field test tracking, observe wellhead leakage and wellbore / wellhead blockage, and evaluate the anti-wax effect and validity period.

[0127] Real-time tracking of production, casing pressure, wellhead temperature and other data, observation of wellhead leakage every half hour, and determination of whether the wellbore / wellhead is blocked based on on-site production conditions;

[0128] Oil samples were taken every 2 hours in the early stage of drainage, and every 1-2 days after the production stabilized. The condensate point was measured before and after the injection of solid wax inhibitor to evaluate the wax inhibitor effect and validity period.

[0129] S9: Solid paraffin inhibitor has an effective period. The filling cycle is adjusted according to production and experimental analysis. The filling cycle of this well is 20 days, and the single addition amount is 50kg. Before the next delivery, the well should be cleared to ensure that the wellbore is unobstructed before delivery.

[0130] In summary, the present invention optimizes the process of solid paraffin inhibitor to make it suitable for high-pressure condensate gas wells, thereby meeting the production demand for long-term paraffin inhibition in high-pressure condensate gas wells.

[0131] Finally, it should be noted that the above is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, it is still possible for those skilled in the art to modify the technical solutions described in the aforementioned embodiments or to make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A solid paraffin inhibitor process for high-pressure condensate gas wells, characterized in that: include: Determine the depth of the solid wax inhibitor receiving device in the wellbore according to the wax precipitation depth of the high-pressure condensate gas well; Performing well-drilling operations and lowering a wellbore receiving device according to the lowering depth; Install a wellhead injection device connected to the upper part of the wellhead gas tree and inject solid wax inhibitor into the wellbore receiving device; Conduct field test tracking, observe wellhead leakage and wellbore / wellhead blockage, and evaluate the anti-wax effect and validity period; The filling cycle and single addition amount of the solid wax inhibitor are adjusted according to the field test tracking results.

2. The solid paraffin inhibitor process for high-pressure condensate gas wells according to claim 1, characterized in that: Before judging the wellbore blockage and wax precipitation depth of the high-pressure condensate gas well, the following steps are included: Determine whether the wellbore / wellhead is blocked based on the on-site production situation of the high-pressure condensate gas well; The depth of wellbore blockage is determined based on previous well cleaning operations or continuous tubing dredging operations, thereby determining the depth of wax precipitation.

3. The solid paraffin inhibitor process for high-pressure condensate gas wells according to claim 2, characterized in that: When there is no previous well cleaning operation or continuous tubing dredging operation, the wax precipitation depth is simulated using phase prediction software based on the PVT analysis data of high-pressure condensate gas wells or oil and gas component analysis data.

4. The solid paraffin inhibitor process for high-pressure condensate gas wells according to claim 2, characterized in that: The wax precipitation depth is 50-500m.

5. The solid paraffin inhibitor process for high-pressure condensate gas wells according to claim 1, characterized in that: The method of performing well-clearing operation and lowering the receiving device into the wellbore according to the lowering depth includes: The immersion depth is not less than the wax precipitation depth.

6. The solid paraffin inhibitor process for high-pressure condensate gas wells according to claim 2, characterized in that: When the wellbore receiving device is multi-level, the wellbore receiving device at the bottom layer can go down to the bottom of the wellbore or the depth of the production layer.

7. The solid paraffin inhibitor process for high-pressure condensate gas wells according to claim 5, characterized in that: The wellbore receiving device is of level 2-3, and the wellbore receiving device is clamped with the inner wall of the oil pipe through a slip, and the slip is released by lifting the wellbore receiving device.

8. The solid paraffin inhibitor process for high-pressure condensate gas wells according to claim 1, characterized in that: The well cleaning operation includes "wire operation + well cleaning rules" well cleaning or continuous tubing dredging operation well cleaning.

9. The solid paraffin inhibitor process for high-pressure condensate gas wells according to claim 1, characterized in that: The method of installing a wellhead injection device on the upper part of the wellhead gas tree and injecting a solid wax inhibitor into the wellbore receiving device comprises: Step 1: Install the wellhead injection device on the top of the wellhead gas tree and test the pressure; Step 2: closing the blind plug and manual gate valve of the wellhead injection device after the pressure test is qualified; Step 3: Open the blind plug of the wellhead injection device to release the gas pressure in the wellhead injection device to zero; Step 4: After the pressure is released, the solid wax inhibitor is placed from the blind plug into the wellhead injection device, and then the blind plug is closed and the manual gate valve is opened to allow the solid wax inhibitor to fall to the wellbore receiving device; Step 5: Repeat steps 2 to 4 until the amount of solid wax inhibitor injection reaches the preset amount; Step 6: Close the blind plug and manual gate valve.

10. A solid paraffin inhibitor process for high-pressure condensate gas wells according to claim 9, characterized in that: The wellhead injection device is a tubular structure with blind plugs and manual gate valves at both ends, and one end close to the manual gate valve is installed and connected to the upper part of the wellhead gas production tree.

11. The solid paraffin inhibitor process for high-pressure condensate gas wells according to claim 1, characterized in that: The field test tracking is carried out to observe the wellhead leakage and wellbore / wellhead blockage, and evaluate the anti-wax effect and validity period, including: Track production, casing pressure and wellhead temperature in real time, regularly observe whether there is leakage at the wellhead, and determine whether the wellbore / wellhead is blocked based on on-site production conditions; Oil samples are taken regularly before drainage and after production stabilizes, and the condensate point is measured before and after the injection of solid wax inhibitor to evaluate the wax inhibitor effect and validity period.

12. A solid paraffin inhibitor device for high-pressure condensate gas wells, characterized in that: include: A lowering depth determination module is used to determine the lowering depth of the solid wax inhibitor wellbore receiving device according to the wax precipitation depth of the high-pressure condensate gas wellbore; A wellbore receiving device lowering module is used to perform well-clearing operations and lower the wellbore receiving device according to the lowering depth; A solid wax inhibitor injection module is used to be installed on the upper part of the wellhead gas tree and connected to the wellhead injection device and inject the solid wax inhibitor into the wellbore receiving device; Field test tracking module, used to track field tests, observe wellhead leakage and wellbore / wellhead blockage, and evaluate the anti-wax effect and validity period; The filling cycle and single addition amount adjustment module is used to adjust the filling cycle and single addition amount of the solid wax inhibitor according to the field test tracking results.

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