Direct injection type drilling fluid degasser and use method

Abstract

The invention relates to the technical field of drilling fluid degassing devices and using methods, in particular to a direct injection type drilling fluid degasser and a using method.The direct injection type drilling fluid degasser comprises a liquid collecting tank, an auxiliary tank, an elevated pipe and a degasser, the degasser comprises a degasser cylinder, the degasser cylinder is hung and fixed in the liquid collecting tank, a stirring mechanism is arranged in the degasser cylinder, and the auxiliary tank is connected with the elevated pipe; a liquid inlet is formed in the lower portion of the degassing cylinder and fixedly communicated with a leading-in mechanism, an outlet of the elevated pipe corresponds to an inlet of the leading-in mechanism, a liquid outlet is formed in the upper portion of the degassing cylinder, and an overflow groove is formed in the inner side, corresponding to the liquid outlet, of the degassing cylinder. The method has the technical advantages that data distortion caused by repeated degassing after the degassed drilling fluid is mixed with the new drilling fluid can be avoided, the removed gas can only be discharged from the gas outlet, the method has a good degassing effect and data consistency on the drilling fluid, and an accurate stratum real data basis is provided for reservoir identification and evaluation.

Description

Technical Field

[0001] This invention relates to the technical field of drilling fluid degassing devices and methods of use, specifically a direct-injection drilling fluid degasser and its method of use. Background Technology

[0002] Gas logging is a logging technique used while drilling to discover formation oil and gas shows, evaluate formation oil and gas content, and determine the wellbore pressure balance. It is one of the important supporting technologies for oil and gas exploration and development. When an oil and gas reservoir is encountered, the natural gas contained in the reservoir seeps into the drilling fluid and circulates to the wellhead. By degassing the drilling fluid returned from the wellhead, the degassed gas is sent to a gas chromatograph for analysis to detect the total amount, composition, and content of hydrocarbons. Gas logging interpretation models and methods are used to evaluate the properties of reservoir fluids and determine reservoir thickness and formation energy. The characteristics of single gas shows, pulled-down gas shows, and aftereffect gas shows are analyzed to determine the balance between formation pressure and drilling fluid column pressure, providing a basis for adjusting drilling fluid density and performance. Therefore, accurately obtaining gas logging data corresponding to the formation is crucial to ensuring the quality and effectiveness of gas logging. If the gas logging data is inconsistent with the formation data, it will directly lead to the identification of oil, gas, and water layers, deviations in the interpretation intervals, and the selection of testing intervals.

[0003] Degassers are essential equipment for obtaining formation natural gas samples during gas logging. Currently, the most widely used degassers are electrically agitated degassers (see...). Figure 1 To ensure stable drilling fluid volume, the degasser is installed inside the outlet buffer tank, using a bottom-entry suction method. Due to the large volume of the buffer tank, the injected drilling fluid first fills the lower space before entering the degasser from the inlet. This makes it impossible to guarantee the correspondence between the degassed drilling fluid and the drilling fluid returned from the current formation. The larger the buffer tank volume, the longer the internal drilling fluid renewal time, causing mixing between new and old formation drilling fluids. This leads to distortion of degassing analysis data, inconsistent with the actual formation conditions. When degassed drilling fluid is returned from the outlet and re-injected into the buffer tank, some mixes with the liquid inside, potentially causing secondary or tertiary degassing, affecting the quality of collected gas samples and the reliability of analytical data. With the outlet constantly open and the overflow surface low, some degassed gas escapes from the outlet, resulting in gas loss and lower analytical data values. Rock cuttings and debris settling at the bottom of the buffer tank can easily clog the inlet. These issues will directly affect the accuracy of gas logging analysis data and reduce the accuracy of well logging oil, gas and water layer identification. Summary of the Invention

[0004] This invention provides a direct-injection drilling fluid degasser and its usage method, which overcomes the shortcomings of the prior art. It can avoid the data distortion caused by mixing of degassed drilling fluid and the return of degassed drilling fluid to the degassing cylinder for repeated degassing.

[0005] One of the technical solutions of the present invention is achieved through the following measures: a direct-injection drilling fluid degasser, comprising a collection tank, an auxiliary tank, an overhead pipe, and a degassing device. The degassing device includes a degassing cylinder, which is suspended and fixed in the collection tank. A stirring mechanism is provided inside the degassing cylinder. An inlet is provided at the lower part of the degassing cylinder, and an inlet is fixedly connected to an inlet mechanism. The outlet of the overhead pipe corresponds to the inlet of the inlet mechanism. An outlet is provided at the upper part of the degassing cylinder. An overflow groove is provided on the inner side of the degassing cylinder corresponding to the outlet. An outlet pipe is connected to the outlet, and the outlet of the outlet pipe corresponds to the auxiliary tank. An air outlet is provided at the top of the degassing cylinder.

[0006] The following are further optimizations and / or improvements to one of the above-mentioned technical solutions: The aforementioned inlet mechanism may include a guide tube and a collection funnel, with the collection funnel connected to the outlet via the guide tube.

[0007] The aforementioned overhead pipe can be tilted from left to right, and the liquid collection funnel is tilted from left to right. A rock cuttings discharge outlet is provided on the lower side of the inlet of the liquid collection funnel near the outlet of the overhead pipe.

[0008] A filter screen can be fixedly installed inside the liquid collection funnel near the rock cuttings discharge outlet.

[0009] The aforementioned filter screen can be in the shape of an arc with the opening facing left.

[0010] The aforementioned direct-injection drilling fluid degasser may also include a tank body, with a partition inside the tank body dividing the tank body into a collection tank and an auxiliary tank, and the degassing cylinder on the outlet side being fixed together with the partition.

[0011] The aforementioned stirring mechanism may include a stirring shaft, with a stirring paddle disposed at the lower part of the stirring shaft.

[0012] The aforementioned degassing device may also include a drive mechanism, which is a motor, with the power output end of the motor connected to the upper end of the stirring shaft.

[0013] The second technical solution of the present invention is achieved through the following measures: a method of using a direct injection drilling fluid degasser, comprising: drilling fluid is transported to a collection funnel through an overhead pipe, and then input into a degassing cylinder from the inlet through a guide pipe; the drilling fluid is agitated and degassed in the degassing cylinder; the degassed drilling fluid enters an overflow tank and is discharged into an auxiliary tank through a discharge pipe at the outlet; the gas removed from the drilling fluid is discharged through the gas outlet.

[0014] When using the direct-injection drilling fluid degasser described in this invention to degas drilling fluid, the newly arrived drilling fluid directly enters the degassing cylinder through the inlet mechanism. The degassed gas is discharged through the outlet. The overflow trough prevents the degassed gas from following the degassed drilling fluid out of the degassing cylinder, ensuring that the degassed gas can only be discharged from the outlet. Furthermore, as the newly arrived drilling fluid enters the degassing cylinder, the degassed drilling fluid is raised to the overflow trough with the fluid level, allowing for timely discharge of the degassed drilling fluid and preventing repeated degassing due to mixing of the degassed and newly arrived drilling fluid. This technical advantage of avoiding data distortion caused by repeated degassing due to mixing of the degassed and newly arrived drilling fluid, and ensuring that the degassed gas can only be discharged from the outlet, provides excellent degassing effect and data consistency for drilling fluid, offering accurate and reliable formation data for reservoir identification and evaluation. Attached Figure Description

[0015] Appendix Figure 1 This is a schematic diagram of the main structure of an existing degasser.

[0016] Appendix Figure 2 This is a schematic diagram of the main structure of an embodiment of the present invention.

[0017] The codes in the attached diagram are as follows: 1 is the liquid collection tank, 2 is the auxiliary tank, 3 is the elevated pipe, 4 is the degassing cylinder, 5 is the liquid inlet, 6 is the liquid outlet, 7 is the overflow trough, 8 is the outlet pipe, 9 is the air outlet, 10 is the guide pipe, 11 is the liquid collection funnel, 12 is the rock cuttings discharge outlet, 13 is the filter screen, 14 is the baffle, 15 is the stirring shaft, 16 is the stirring paddle, 17 is the motor, and 18 is the buffer tank. A represents the drilling fluid flow direction. Detailed Implementation

[0018] The present invention is not limited to the following embodiments, and the specific implementation can be determined according to the technical solution of the present invention and the actual situation.

[0019] In this invention, for ease of description, the description of the relative positions of the components is based on the appendix to the specification. Figure 2 The layout is described using a diagrammatic method, such as the positional relationships of front, back, top, bottom, left, and right, which are based on the instructions attached. Figure 2 The orientation of the layout is determined by the direction of the map.

[0020] The present invention will be further described below with reference to embodiments: Example 1: As shown in the attached document Figure 2As shown, the direct-injection drilling fluid degasser includes a collection tank 1, an auxiliary tank 2, an overhead pipe 3, and a degassing device. The degassing device includes a degassing cylinder 4, which is suspended and fixed in the collection tank 1. A stirring mechanism is installed inside the degassing cylinder 4. An inlet 5 is provided at the lower part of the degassing cylinder 4, and an inlet mechanism is fixedly connected to the inlet 5. The outlet of the overhead pipe 3 corresponds to the inlet of the inlet mechanism. An outlet 6 is provided at the upper part of the degassing cylinder 4. An overflow groove 7 is provided inside the degassing cylinder 4 corresponding to the outlet 6. An outlet pipe 8 is connected to the outlet 6, and the outlet of the outlet pipe 8 corresponds to the auxiliary tank 2. An air outlet 9 is provided at the top of the degassing cylinder 4.

[0021] This direct-injection drilling fluid degasser can avoid the mixing of new and old formation fluids (i.e., drilling fluid). The degassed gas comes from the newest formation fluid, ensuring the consistency and continuity of the analysis results of the degassed gas with the formation.

[0022] After degassing, the drilling fluid is discharged directly from outlet 6 into auxiliary tank 2, which will not interfere with the degassing results of the new formation drilling fluid and can provide samples for the performance analysis of the degassed drilling fluid.

[0023] Example 2: As shown in the attached document Figure 2 As shown, as an optimization of the above embodiment, the inlet mechanism includes a guide tube 10 and a liquid collection funnel 11, and the liquid collection funnel 11 is connected to the liquid outlet 6 through the guide tube 10.

[0024] The drilling fluid entering the collection funnel 11 is directly injected into the degassing cylinder 4 through the guide pipe 10, ensuring that the degassing drilling fluid is fresh drilling fluid corresponding to the current formation.

[0025] By using the ratio of the liquid volume flowing into the guide pipe 10 to the discharge volume at the outlet 6, the degassing coefficient can be corrected, the analytical data can be corrected, and more accurate measurement results can be obtained.

[0026] Example 3: As an optimization of Example 2 above, the overhead pipe 3 is inclined from left to right, the liquid collection funnel 11 is inclined from left to right, and a rock cuttings discharge outlet 12 is provided on the lower side of the inlet of the liquid collection funnel 11 near the outlet side of the overhead pipe 3.

[0027] The guide pipe 10 guides the drilling fluid to the bottom of the degassing cylinder 4, and the overflow liquid level is raised through the overflow trough 7. The guide pipe 10 and the overflow trough 7 jointly control the flow direction and renewal of the liquid in the degassing cylinder 4, and prevent the degassing gas from escaping from the liquid outlet 6.

[0028] Example 4: As shown in the appendix Figure 2 As shown, as an optimization of the above embodiment, a filter screen 13 is fixedly installed inside the liquid collection funnel 11 near the rock cuttings outlet 12.

[0029] Example 5: As an optimization of the above embodiment, in order to adapt to the impact of drilling fluid flowing out of the overhead pipe 3, the filter screen 13 is an arc shape with the opening facing left.

[0030] Large particles of rock cuttings and other impurities are filtered out through the filter screen 13, ensuring the cleanliness of the drilling fluid entering the degassing cylinder 4.

[0031] Example 6: As attached Figure 2 As shown, as an optimization of the above embodiment, the direct injection drilling fluid degasser also includes a tank body, and a partition 14 is provided inside the tank body to divide the tank body into a liquid collection tank 1 and an auxiliary tank 2. The degassing cylinder 4 on the side of the liquid outlet 6 is fixed together with the partition 14.

[0032] The design described in Example 6 can integrate the liquid collection tank 1 and the auxiliary tank 2 into one unit.

[0033] Example 7: As attached Figure 2 As shown, as an optimization of the above embodiment, the stirring mechanism includes a stirring shaft 15, and a stirring paddle 16 is provided at the lower part of the stirring shaft 15.

[0034] Example 8: As attached Figure 2 As shown, as an optimization of the above embodiment, the degassing device also includes a drive mechanism, which is a motor 17, and the power output end of the motor 17 is connected to the upper end of the stirring shaft 15.

[0035] Example 9: As attached Figure 2 As shown, the method of using the direct-injection drilling fluid degasser described in the above embodiment includes: drilling fluid is transported to the collection funnel 11 through the overhead pipe 3; after the drilling fluid passes through the filter screen 13 in the collection funnel 11 to filter large rock cuttings, it is then fed into the degassing cylinder 4 from the inlet 5 through the guide pipe 10; the drilling fluid is agitated and degassed in the degassing cylinder 4; after the degassed drilling fluid enters the overflow tank 7, it is discharged into the auxiliary tank 2 through the outlet pipe 8 at the outlet 6; the gas degassed from the drilling fluid is discharged through the gas outlet 9, and the discharged gas is used for gas analysis.

[0036] The above technical features constitute the embodiments of the present invention, which have strong adaptability and implementation effect. Unnecessary technical features can be added or removed according to actual needs to meet the needs of different situations.

Claims

1. A direct injection drilling fluid degasser characterized by The device comprises a collecting tank, an auxiliary tank, an overhead pipe and a degassing device, the degassing device comprises a degassing cylinder which is suspended and fixed in the collecting tank, a stirring mechanism is arranged in the degassing cylinder, a liquid inlet is arranged at the lower part of the degassing cylinder, a guide-in mechanism is fixedly connected to the liquid inlet, the outlet of the overhead pipe corresponds to the inlet of the guide-in mechanism, a liquid outlet is arranged at the upper part of the degassing cylinder, an overflow groove is arranged at the inner side of the degassing cylinder corresponding to the liquid outlet, a guide-out pipe is connected to the liquid outlet, the outlet of the guide-out pipe corresponds to the auxiliary tank, and a gas outlet is arranged at the top of the degassing cylinder.

2. The direct pour drilling fluid degasser of claim 1, wherein The guide-in mechanism comprises a flow guide pipe and a collecting funnel, and the collecting funnel is connected to the liquid outlet through the flow guide pipe.

3. The direct pour drilling fluid degasser of claim 2, wherein The overhead pipe is inclined from the upper left to the lower right, the collecting funnel is also inclined from the upper left to the lower right, and a cuttings discharge outlet is arranged at the lower side of the inlet of the collecting funnel close to the outlet side of the overhead pipe.

4. The direct pour drilling fluid degasser of claim 2 or 3, wherein A filter screen is fixedly arranged in the collecting funnel close to the cuttings discharge outlet.

5. The direct pour drilling fluid degasser of claim 4, wherein The filter screen is in the shape of an arc with the opening facing left.

6. The direct pour drilling fluid degasser of claim 2 or 3 or 5, wherein The device further comprises a tank body, a partition plate is arranged in the tank body to divide the tank body into the collecting tank and the auxiliary tank, and the degassing cylinder at the liquid outlet side is fixed to the partition plate.

7. The direct pour drilling fluid degasser of claim 4 wherein The device further comprises a tank body, a partition plate is arranged in the tank body to divide the tank body into the collecting tank and the auxiliary tank, and the degassing cylinder at the liquid outlet side is fixed to the partition plate.

8. The direct pour drilling fluid degasser of any one of claims 2 to 7, wherein The stirring mechanism comprises a stirring shaft, and a stirring paddle is arranged at the lower part of the stirring shaft.

9. The direct pour drilling fluid degasser and method of use of claim 8, wherein The degassing device further comprises a driving mechanism, the driving mechanism is an electric motor, and the power output end of the electric motor is connected to the upper end of the stirring shaft.

10. A method of using the direct pour drilling fluid degasser of any one of claims 2 to 9, characterized by The device comprises: The drilling fluid is conveyed to the collecting funnel through the overhead pipe, then input into the degassing cylinder through the liquid inlet from the flow guide pipe, the drilling fluid is degassed by stirring in the degassing cylinder, the degassed drilling fluid is discharged into the auxiliary tank through the guide-out pipe at the liquid outlet after entering the overflow groove, and the gas removed from the drilling fluid is discharged through the gas outlet.

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