A test system for simulating the sedimentation of drilling mud in a drilling method and a test method thereof

Abstract

The application provides a test system and test method for simulating drilling mud sedimentation in a drilling method, and belongs to the technical field of mud sedimentation tests. The test system comprises a mud preparation unit, a mud storage unit, a residue storage unit, a mixing unit, a sedimentation unit and a separation unit. The test system and test method for simulating drilling mud sedimentation in a drilling method are characterized in that the position and number of transverse partitions and longitudinal partitions are adjusted, and the slot depth compensation function is cooperated, so that a single test platform capable of independently adjusting multiple factors such as mud proportioning, conveying flow, residue supply amount, sedimentation zone lateral size, sedimentation stage and longitudinal size of each stage is constructed by using a relatively simple structure. The test platform has high operation convenience and strong adjustment flexibility, and provides an efficient and convenient test method for systematic test research on the sedimentation mechanism of drilling mud in a drilling method.

Description

Technical Field

[0001] This invention relates to the field of mud sedimentation testing technology, specifically to a test system and method for simulating well drilling mud sedimentation. Background Technology

[0002] The coal-bearing strata in the western mining areas are mostly typical water-rich, weakly cemented bedrock formations with poor strata stability. Mine construction primarily employs freezing and drilling methods. Compared to freezing, drilling offers significant advantages such as higher construction safety, greater mechanization, better well quality, and no aquifer limitations, making it the mainstream construction method for large vertical shafts in the western mining areas in the future.

[0003] The core technology of well drilling lies in the circulation and purification of drilling mud: the mud circulation carries the rock cuttings broken by the drill bit at the bottom of the well to the surface, where the mud and cuttings are separated through settling in the surface mud sedimentation tank. The separated clear mud is then reinjected into the wellbore for reuse. However, in engineering practice in water-rich and weakly cemented formations in western China, factors such as unreasonable design of the surface sedimentation tank volume and poor matching of the sedimentation zone size and number of stages often lead to prominent engineering problems such as poor drilling cuttings sedimentation and the return of fine rock cuttings to the wellbore. This directly results in the continuous accumulation of solid phase content in the mud, a sharp deterioration in the mud rheological properties, and consequently, the thickening of bottom sediment, accelerated drill bit wear, and even major safety hazards such as stuck drill bits or burying drill bits. Therefore, it is urgent to conduct in-depth research on the influence of mud properties, rock cuttings particle size, mud circulation flow rate, and especially the geometric design dimensions and number of sedimentation stages of the mud sedimentation tank on the mud-cutting separation effect.

[0004] Currently, domestic and international laboratory experimental research on drilling fluids / mud mainly focuses on the following two categories:

[0005] The first category is the testing of rheological properties of mud-based liquids, such as using a rotational viscometer to measure intrinsic parameters like dynamic shear force and plastic viscosity of muds with different proportions, in order to optimize mud formulations.

[0006] The second type is the static high-pressure settling stability test, which involves placing the prepared drilling fluid in a sealed container and letting it stand, and testing the settling rate of the weighting material (such as barite) under high temperature and high pressure to evaluate the stability of the mud in the wellbore static state.

[0007] It is worth noting that the existing experimental devices and methods are not physical simulations of the "dynamic slurry-slag separation effect in the surface mud sedimentation tank". In particular, there are few reports in domestic and foreign literature and patents on how the geometric configuration of the sedimentation tank (lateral width, longitudinal depth, and number of sedimentation stages) affects the solid-liquid separation efficiency. The main reason is that simulating the sedimentation effect of real drilling mud is an extremely complex multi-factor strongly coupled system engineering. Its influencing factors include at least: (1) rheological parameters such as viscosity and density of mud; (2) particle size distribution and shape of rock cuttings; (3) inlet flow velocity and flow rate of mixed mud; (4) lateral dimensions of the sedimentation zone (affecting the horizontal flow velocity of mud, which in turn determines the horizontal displacement distance of rock cuttings); (5) longitudinal depth of the sedimentation zone (affecting the settling distance of rock cuttings, which determines the theoretical settling velocity according to Stokes' law); (6) number of sedimentation stages (affecting the stability of the mud flow from turbulent to laminar flow).

[0008] To address the aforementioned technological gaps and experimental bottlenecks, there is an urgent need to develop a simulated drilling mud sedimentation test system that can flexibly and continuously adjust the lateral dimensions, longitudinal depth, and sedimentation stages of the sedimentation zone on a single test platform. This system should be complemented by a dynamic test method capable of simulating continuous mud carrying and continuous flow sedimentation. This will enable the study of mud sedimentation mechanisms under the coupled influence of multiple factors, providing reliable experimental data support and theoretical basis for the design of surface mud purification systems for drilling in water-rich, weakly cemented formations in western China. Summary of the Invention

[0009] This invention provides a test system for simulating well drilling mud sedimentation, comprising a mud preparation unit, a mud storage unit, a slag storage unit, a mixing unit, a sedimentation unit, and a separation unit. The mud preparation unit intermittently replenishes simulated mud to the mud storage unit, the mud storage unit continuously supplies simulated mud to the mixing unit, and the slag storage unit supplies simulated rock cuttings to the mixing unit. The mixing unit mixes the simulated rock cuttings with the simulated mud. A flow rate regulation and monitoring unit is provided between the mud storage unit and the mixing unit. The capacity of the mud storage unit at least covers all the needs of the mixing unit during the mud preparation period. The sedimentation unit includes a transparent box, transverse diaphragms, and longitudinal diaphragms. The transverse diaphragms can move laterally to adjust the lateral dimensions of the sedimentation zone. The longitudinal diaphragms are located between the transverse diaphragms and the sidewall of the box, can move longitudinally, and their number is variable to adjust the sedimentation process. The sedimentation zone has several stages and longitudinal dimensions for each stage. The horizontal partitions and the housing, as well as the longitudinal partitions and the transparent housing, are sealed and fixed by connecting structures. These connecting structures include clamps and locking elements. The clamps span the side walls of the corresponding components and have slots on their inner sides. When the locking elements are tightened, the clamps are pressed against the side walls of the corresponding components, and the ends of the horizontal or longitudinal partitions are inserted into the corresponding slots to form a sealed connection and fixation. When the locking elements are loosened, the clamps can move in the corresponding direction. An inclined guide groove is provided between the sedimentation unit and the mixing unit to allow the mixed slurry to flow smoothly into the sedimentation unit. The system also includes a vision unit for detecting sedimentation speed, a separation unit for receiving and separating the mixed slurry discharged from the sedimentation unit, and a sensing unit for measuring the weight of the mixed slurry discharged from the sedimentation unit.

[0010] In one possible implementation, the partition plate has multiple transverse dimensions, and the slots corresponding to the partition plate have a preset depth in the transverse direction. The partition plate can form a sealed fit with the slot at any insertion position within the preset depth range of the corresponding slot. By changing the insertion depth of the partition plate of the same transverse dimension into the corresponding slot, the effective separation position of the partition plate in the sedimentation zone in the transverse direction is adjusted, so that the partition plate of the same transverse dimension corresponds to multiple different transverse dimension levels.

[0011] In one possible implementation, there are at least two longitudinal partitions. After the longitudinal partitions are installed in the corresponding slots, they form a flow channel connecting the regions on both sides of the longitudinal partitions. Along the longitudinal flow direction, the lowest flow point of the flow channel decreases step by step.

[0012] In one possible implementation, the mud preparation unit includes at least two containment tanks and a mixing tank, with the containment tanks connected to the mixing tank via conduits, and the conduits being equipped with flow regulation and monitoring units.

[0013] In one possible implementation, the slurry storage unit and the mixing unit, as well as the mixing tank and the slurry storage unit, are connected by conduits. Each conduit is equipped with a water pump, and the inlet end of each conduit is equipped with a filter screen for filtering impurities.

[0014] In one possible implementation, the front side of the chamber is provided with transverse and longitudinal measuring lines, which are arranged at calibrated distances to locate the position of the simulated rock debris in real time. The vision unit is set at a preset distance on the front side of the chamber and is used to record the entire experimental process.

[0015] In one possible implementation, the simulated rock debris within the slag storage unit has a specified particle size and different sizes of simulated rock debris have different colors.

[0016] A test method for a test system simulating well drilling mud sedimentation, based on a test system simulating well drilling mud sedimentation, includes the following steps:

[0017] S1 Preparation Stage: Adjust the position and specifications of the transverse and longitudinal partitions according to the predetermined plan, determine the transverse dimensions, number of stages, and depth and longitudinal dimensions of each stage of the sedimentation zone, prepare simulated mud in the mud preparation unit and send the prepared simulated mud to the mud storage unit 2, and load simulated rock debris into the slag storage unit.

[0018] S2 test operation phase: Simulated mud and simulated rock debris are continuously supplied to the mixing unit at a predetermined flow rate. After mixing, they are gently fed into the sedimentation unit through an inclined guide chute. The vision unit is activated to record the entire process. The separation unit receives the mixed mud discharged from the sedimentation unit.

[0019] S3 Data Processing and Evaluation Stage: Evaluation Index 1 (Graded Settling Velocity) The video recorded by the visual unit is decomposed frame by frame into photos. Combined with PIV technology, the displacement field of the simulated rock debris in adjacent photos is converted into a velocity field to obtain the average settling velocity of each stage of simulated rock debris in the sedimentation zone.

[0020] Evaluation index 2 (total sedimentation efficiency): Weigh the weight m of the simulated rock slag received by the separation unit and the weight M of the simulated rock slag released by the slag storage unit, and calculate (1-(m / M))×100%;

[0021] Evaluation index 3 (stage sedimentation efficiency): Weigh the simulated rock debris (mi) in each stage of the sedimentation zone and calculate (mi / M) × 100%.

[0022] Evaluation index 4 (slurry carrying rate): The weight of the rock debris (m) in the separation unit is obtained by subtracting the weight of the rock debris (m) from the measured value of the sensing unit. The value of (m / ml) × 100% is the slurry carrying rate.

[0023] S4 Multifactor Analysis Stage: Change the ratio of simulated mud, the flow rate of mixed mud, the flow rate of simulated rock debris, the lateral dimensions and number of stages of the mud sedimentation zone, and the depth and longitudinal dimensions of each stage. Repeat step S3 to obtain the influence of each factor on the sedimentation effect.

[0024] In one possible implementation, the simulated mud mix ratio in step S4 includes the following five types, with corresponding viscosities of 1 mPa·s, 1.7 mPa·s, 5.5 mPa·s, 8.2 mPa·s, and 11 mPa·s, respectively: First, all water; second, brine, with a ratio of 145 g of industrial NaCl per 1000 ml of water; third, a mixture of brine and slime, wherein the brine ratio is 145 g of industrial NaCl per 1000 ml of water, and the slime... The first type is a mixture of salt water and mucus, where the salt water is mixed with 0.1g of cellulose per 500ml of water in a 1:1 ratio; the second type is a mixture of salt water and mucus, where the salt water is mixed with 145g of industrial NaCl per 1000ml of water in a 1:1 ratio; the third type is a mixture of salt water and mucus, where the salt water is mixed with 145g of industrial NaCl per 1000ml of water in a 1:1 ratio; and the fourth type is a mixture of salt water and mucus, where the salt water is mixed with 145g of industrial NaCl per 1000ml of water in a 1:1 ratio.

[0025] In one possible implementation, the preparation processes for the five simulated muds are as follows: When using the first ratio, water is directly added to the slurry storage unit; when using the second ratio, water and industrial NaCl are added to a mixing tank according to the ratio and stirred until the industrial NaCl is completely dissolved before being fed into the slurry storage unit 2; when using the third to fifth ratios, brine is prepared in one container and slurry is prepared in another container according to the ratio, and then the two are fed into a mixing tank according to the ratio and stirred and mixed before being sent to the slurry storage unit.

[0026] The above-mentioned one or more technical solutions in the embodiments of the present invention have the following technical effects: According to the embodiments of the present invention, a test system and test method for simulating well drilling mud sedimentation are provided, and the working process is as follows: First, the mud preparation unit prepares simulated mud according to a preset ratio. After preparation, it is temporarily stored by the mud storage unit and continuously supplied to the mixing unit during the test. At the same time, the simulated rock debris in the slag storage unit continuously falls to the mixing unit under the action of gravity. After the simulated mud and simulated rock debris are fully mixed in the mixing unit, they are gently sent into the sedimentation unit through the inclined guide channel for mud-slag sedimentation separation. The separated mixed mud enters the separation unit for solid-liquid separation and is weighed in real time by the sensing unit.

[0027] During the above-mentioned operation, the operator can flexibly adjust the supply flow rate of the simulated mud through the flow regulation and monitoring unit, adjust the delivery flow rate of the simulated rock cuttings by controlling the valve, and change the viscosity and density of the simulated mud by adjusting the supply ratio of each component in the mud preparation unit. Thus, the operator can independently adjust multiple factors such as mud ratio, delivery flow rate, and rock cuttings supply on a single test platform.

[0028] More importantly, when the configuration of the sedimentation zone needs to be changed, simply loosen the locking mechanism, move the transverse baffle to the target position laterally, and then relock it to change the lateral dimensions of the sedimentation zone. Simultaneously, by increasing or decreasing the number of longitudinal baffles and moving them longitudinally to the target position and then locking them, the number of stages and the longitudinal dimensions of each stage of the sedimentation zone can be changed. This process eliminates the need to manufacture multiple sedimentation tank models of different specifications; only longitudinal baffles of a certain specification are required to meet the experimental needs of different sedimentation zone configurations. Furthermore, the slots have a preset depth laterally, allowing longitudinal baffles of the same lateral dimension to be inserted at different depths to match the spacing changes of the transverse baffles at different lateral positions, further reducing the number of required longitudinal baffles and lowering the baffle manufacturing cost.

[0029] In summary, this invention, through the coordinated operation of adjusting the position and number of transverse and longitudinal diaphragms and the slot depth compensation function, constructs a single test platform with a relatively simple structure that can independently adjust multiple factors such as mud ratio, delivery flow rate, rock cuttings supply, lateral dimensions of the sedimentation zone, number of sedimentation stages, and longitudinal dimensions of each stage. It offers high operational convenience and strong adjustment flexibility, providing an efficient and convenient experimental means for the systematic experimental research on the sedimentation mechanism of drilling mud. Attached Figure Description

[0030] Figure 1 This is a schematic diagram of the structure of an experimental system for simulating well drilling mud sedimentation provided in an embodiment of the present invention;

[0031] Figure 2 This is a schematic diagram of the longitudinal partition of a test system for simulating well drilling mud sedimentation provided in an embodiment of the present invention;

[0032] Figure 3 This is a partial cross-sectional view of the test system for simulating well drilling mud sedimentation provided in an embodiment of the present invention from the front view of the test chamber.

[0033] Figure 4 This is a top-view structural diagram of a slot in a test system for simulating well drilling mud sedimentation provided in an embodiment of the present invention.

[0034] Figure 5 This is a schematic diagram of the state where the slot is not filled by the end of the longitudinal partition plate from a top view in a test system for simulating well drilling mud sedimentation provided by an embodiment of the present invention.

[0035] In the diagram: 1. Slurry preparation unit; 101. Container tank; 102. Mixing tank; 2. Slurry storage unit; 3. Slag storage unit; 31. Feed inlet; 32. Discharge outlet; 33. Rock debris placement box; 34. Discharge control valve; 4. Mixing unit; 5. Sedimentation unit; 51. Box body; 52. Horizontal partition; 53. Vertical partition; 54. Frame clamp; 55. Slot; 56. Locking element; 6. Separation unit; 61. Slurry-slag separation box; 62. Rock debris isolation net; 7. Flow regulation and monitoring unit; 71. Flow meter; 72. Valve; 8. Inclined guide channel; 9. Vision unit; 10. Sensing unit; 11. Conduit; 12. Water pump; 13. Filter screen. Detailed Implementation

[0036] To make the above-mentioned objects, features, and advantages of the present invention more apparent and understandable, specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of the present invention. However, the present invention can be implemented in many other ways different from those described below, and those skilled in the art can make similar modifications without departing from the spirit of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0037] Please see Figures 1-5 A test system for simulating well drilling mud sedimentation includes a mud preparation unit 1, a mud storage unit 2, a slag storage unit 3, a mixing unit 4, a sedimentation unit 5, a separation unit 6, a sensing unit 10, and an inclined guide trough 8.

[0038] (I) Mud Preparation Unit 1

[0039] The mud preparation unit 1 is used to prepare simulated mud with different proportions and intermittently supply it to the mud storage unit 2.

[0040] Specifically, the mud preparation unit 1 includes two container tanks 101 and one mixing tank 102. Both container tanks 101 and mixing tank 102 are made of acrylic material and are one meter in length, width, and height. One container tank 101 is used to prepare brine, and the other container tank 101 is used to prepare slime. The two container tanks 101 are connected to the mixing tank 102 via conduits 11. When preparing simulated mud, brine and slime are supplied to the mixing tank 102 from their respective container tanks 101 via conduits 11 according to a preset flow rate ratio. The mixing tank 102 is equipped with a stirrer to thoroughly mix the brine and slime supplied to the mixing tank 102 to produce a uniform simulated mud.

[0041] A flow regulation and monitoring unit 7 and a water pump 12 are installed on the conduit 11. The flow regulation and monitoring unit 7 includes a flow meter 71 and a valve 72. The valve 72 is used to regulate the flow rate of the brine and the viscous liquid respectively, and the flow meter 71 is used to record the flow rates of the brine and the viscous liquid in real time. Through the real-time monitoring feedback of the flow meter 71, the operator can precisely adjust the opening of the valve 72 to ensure that the two liquid components are supplied to the mixing tank 102 strictly according to the preset ratio, thus ensuring the accuracy of the simulated mud ratio. The water pump 12 provides power for the transport of brine and viscous liquid from the receiving tank 101 to the mixing tank 102.

[0042] (ii) Slurry storage unit 2

[0043] The slurry storage unit 2 is connected to the mixing tank 102 via a conduit 11. A water pump 12 is installed on the conduit 11 to deliver the simulated mud prepared in the mixing tank 102 to the slurry storage unit 2.

[0044] In this embodiment, the slurry storage unit 2 has a capacity of 3000 liters and continuously supplies simulated mud to the mixing unit 4. While the slurry storage unit 2 continuously supplies simulated mud to the mixing unit 4, the mud preparation unit 1 simultaneously prepares the next batch of simulated mud. Throughout the mud preparation period, the capacity of simulated mud in the slurry storage unit 2 is sufficient to fully meet the continuous needs of the mixing unit 4, ensuring that the experiment can be carried out continuously and without interruption. This, in turn, fully meets the requirements for long-term continuous operation of the experiment within a limited space environment.

[0045] (III) Slag Storage Unit 3

[0046] The slag storage unit 3 includes a slag placement box 33, which has a feed inlet 31 at the top and a discharge outlet 32 ​​at the bottom. Simulated slag is fed into the slag placement box 33 through the feed inlet 31, and a discharge control valve 34 is provided at the discharge outlet 32 ​​to control the flow rate of simulated slag to the mixing unit 4.

[0047] The rock slag placement box 33 has graduation lines (not shown in the figure) on its side wall. During the test preparation stage, simulated rock slag is fed into the rock slag placement box 33 through the feed inlet 31 until the accumulation height of the simulated rock slag reaches the graduation line, so that the rock slag placement box 33 can hold a certain amount of simulated rock slag. The graduation line allows the operator to accurately control the initial rock slag volume in the rock slag placement box 33 in each test. During the test operation stage, the operator opens the discharge control valve 34 to the preset opening degree. After the discharge control valve 34 reaches the preset flow state, the simulated rock slag in the rock slag placement box 33 continues to fall under its own gravity and is supplied to the mixing unit 4 through the discharge outlet 32. During this process, as the simulated rock slag is continuously discharged, the accumulation height of the rock slag in the rock slag placement box 33 gradually decreases, which may cause the rock slag falling speed to fluctuate due to the decrease in its own weight, thus affecting the stability of the simulated rock slag supply flow rate.

[0048] To further improve the long-term stability of the simulated rock slag conveying flow rate, this embodiment also provides a preferred operating method: during the test operation, the operator or automatic feeding device continuously replenishes the simulated rock slag into the rock slag placement box 33 in real time, so that the volume of simulated rock slag in the rock slag placement box 33 is always maintained near the scale line (i.e., the rock slag accumulation height is always maintained). By maintaining the constant self-weight of the simulated rock slag in the rock slag placement box 33, the stability of the rock slag falling driving force is ensured, and the falling speed of the simulated rock slag is kept consistent, thereby achieving a constant flow rate supply of simulated rock slag to the mixing unit 4. This avoids introducing interference variables into the sedimentation effect evaluation due to fluctuations in the rock slag supply flow rate, thereby improving the accuracy and repeatability of the test data.

[0049] (iv) Hybrid Unit 4

[0050] Mixing unit 4 is a slurry-slag mixer, used to mix simulated mud from slurry storage unit 2 with simulated rock slag from slag storage unit 3 to form a uniform mixed mud.

[0051] Specifically, the mixing unit 4 is equipped with a mud inlet, a rock debris inlet, and a mixed mud outlet (not shown in the figure). The mud inlet is connected to the slurry storage unit 2 via a conduit 11, which is equipped with a flow regulation and monitoring unit 7 and a water pump 12. The flow regulation and monitoring unit 7 includes a flow meter 71 and a valve 72, used for precise control and real-time monitoring of the simulated mud supply flow rate to meet the experimental requirements of the influence of different experimental factors (such as different mud flow rates) on the sedimentation effect. The rock debris inlet is connected to the discharge port 32 of the slag storage unit 3 via a pipeline. The simulated rock debris in the slag storage unit 3 enters the mixing unit 4 through the rock debris inlet after passing through the discharge port 32 and the discharge control valve 34 under gravity. After the simulated mud supplied by the slurry storage unit 2 and the simulated rock debris supplied by the slag storage unit 3 are fully mixed inside the mixing unit 4, the mixture is discharged through the mixed mud outlet and gently fed into the sedimentation unit 5 via the inclined guide trough 8 for sedimentation testing.

[0052] In this embodiment, all inlet ends of the conduits 11 are equipped with filters 13 for filtering impurities. To facilitate replacement and cleaning, the filters 13 are fixed to the inlet ends of the conduits 11 by binding, and the mesh size of the filters 13 is 1mm.

[0053] (V) Precipitation Unit 5

[0054] The sedimentation unit 5 is located at the downstream end of the inclined guide channel 8 and is used to receive and simulate the slurry-sludge separation process of the drilling mud sedimentation tank. The sedimentation unit 5 includes a transparent box 51, a transverse partition 52 and a longitudinal partition 53, and a connecting structure.

[0055] The transparent box 51 is a rectangular box structure with an open top, specifically measuring 4 meters in length, 3 meters in width, and 1 meter in height, and is made of transparent acrylic. This facilitates observation and recording of the simulated rock debris settling process inside the box 51. The interior space of the transparent box 51 forms a sedimentation zone, used to contain the mixed mud from mixing unit 4 and to separate the slurry from the debris through sedimentation.

[0056] 1. Horizontal partition 52

[0057] The diaphragm 52 is a partition set along the longitudinal direction (i.e., the left and right direction). The diaphragm 52 can be moved in the transverse direction (i.e., the front and back direction). By adjusting the transverse position of the diaphragm 52 in the transparent box 51, the transverse dimension (i.e. the width in the front and back direction) of the sedimentation zone can be changed, thereby studying the influence of the width of the sedimentation zone on the horizontal flow velocity of the mixed mud and the sedimentation effect of the rock debris.

[0058] 2. Longitudinal partition 53

[0059] The longitudinal partition 53 is located between the transverse partition 52 and the front side wall of the housing 51. It is a partition arranged transversely (front-to-back) along the transparent housing 51 and is used to classify the sedimentation zone. The longitudinal partition 53 can move longitudinally (left-to-right), and its number is variable. By changing the number and longitudinal installation position of the longitudinal partitions 53, the number of sedimentation zones and the longitudinal dimension of each zone (i.e., the length of each sedimentation zone in the left-to-right direction) can be adjusted. Furthermore, the longitudinal partition 53 has various transverse dimensions (i.e., partitions with different front-to-back widths) to accommodate different experimental requirements for the transverse dimensions of the sedimentation zone, allowing for selection by different experimental schemes.

[0060] 3. Connection Structure

[0061] The horizontal partition 52 is sealed and fixed to the left and right side walls of the box 51, the rear end of the longitudinal partition 53 is sealed to the horizontal partition 52, and the front end of the longitudinal partition 53 is sealed to the front side wall of the box 51 through a connection structure.

[0062] The connecting structure includes a clamp 54 and a locking element 56. The clamp 54 is a U-shaped cross-section member, spanning the side wall of the corresponding component (for example, spanning the side wall of the housing 51, or spanning the transverse partition 52). The portion of the clamp 54 located inside the corresponding component has a slot 55. When the locking element 56 is locked, the clamp 54 is pressed tightly against the side wall of the corresponding component, and the end of the transverse partition 52 or longitudinal partition 53 is inserted into the slot 55 to form a sealed connection and fixation. When the locking element 56 is released, the clamp 54 can move in the corresponding direction to adjust the position of the transverse partition 52 or longitudinal partition 53.

[0063] 4. Connection structure between the diaphragm 52 and the side wall of the housing 51

[0064] The connection structure between the right end of the partition 52 and the right side wall of the housing 51 will be explained in detail as an example. Figure 3 As shown, the clamp 54 spans the right side wall of the housing 51, with one part of the clamp 54 located on the outer side of the right side wall of the housing 51 and the other part located on the inner side of the right side wall of the housing 51. The locking element 56 is threadedly connected to the portion of the clamp 54 located on the outer side of the housing 51. Figure 3As shown, there are two locking elements 56, spaced apart vertically. Both locking elements 56 penetrate the portion of the clamp 54 located on the outside of the housing 51 in the left-right direction. The ends of the locking elements 56 near the outer wall of the housing 51 are rotatably connected to contact ends (such as circular or disc-shaped pressure heads). During locking, the operator twists the locking elements 56, causing the contact ends to move closer to the outer wall of the housing 51 and press against it. Then, the operator continues to tighten the locking elements 56, using the reaction force of the threaded feed to gradually move the portion of the clamp 54 located inside the housing 51 closer to the inner wall of the housing 51 until it is tightly against the right side wall of the housing 51, at which point the clamp 54 is in a fixed state. The slot 55 on the side wall portion of the clamp 54 is then fixed in a preset position.

[0065] The connection structure between the left end of the partition 52 and the left side wall of the housing 51 is similar, that is, a bracket 54 is also provided across the left side wall of the housing 51, and it is fixed by the same locking element 56. After the brackets 54 on both sides are fixed, the left and right ends of the partition 52 are inserted into the slots 55 of the brackets 54 on the left and right sides respectively, and the sealed and fixed installation of the partition 52 is completed.

[0066] When it is necessary to adjust the position of the partition 52 in the horizontal (front and back direction), simply loosen the locking member 56 first to separate the contact end from the outer wall of the box 51, release the clamping force between the clamp 54 and the side wall of the box 51, and then move the clamp 54 longitudinally to the preset position, and then lock the locking member 56 again to complete the re-fixing.

[0067] To further improve the sealing performance of the partition 52 after installation, sealing strips (not shown in the figure) are provided on both the front and rear sides of the left and right ends of the partition 52. The sealing strips are preferably elastic sealing strips made of rubber or silicone. When the end of the partition 52 is inserted into the slot 55, the sealing strip is deformed under pressure, filling the gap between the end of the partition 52 and the inner wall of the slot 55, forming an elastic seal, which effectively prevents the mixed slurry from flowing out from the gap between the partition 52 and the side wall of the box 51.

[0068] 5. Connection structure between longitudinal partition 53 and box body 51 and transverse partition 52

[0069] In the connection structure between the front end of the longitudinal partition 53 and the front side wall of the box 51, the bracket 54 is installed on the front side wall of the box 51. Its fixing method is the same as that of the connection structure of the transverse partition 52. That is, the bracket 54 spans the front side wall of the box 51 and is fixed by the locking member 56 pressing against the front side of the front side wall of the box 51. The front end of the longitudinal partition 53 is inserted into the slot 55 inside the bracket 54 to form a sealed connection.

[0070] In the connection structure between the rear end of the longitudinal partition 53 and the transverse partition 52, the bracket 54 is installed on the transverse partition 52 (i.e., the bracket 54 spans across the side wall of the transverse partition 52), and is fixed by the locking member 56 pressing against the rear side of the transverse partition 52. The rear end of the longitudinal partition 53 is inserted into the slot 55 inside the bracket 54 to form a sealed connection.

[0071] It is important to note that the transverse partitions 52 should be installed first, and the longitudinal partitions 53 should be installed only after the transverse partitions 52 are fixed. This is because the brackets 54 at the rear end of the longitudinal partitions 53 are installed on the transverse partitions 52, and the installation position of the longitudinal partitions 53 can only be determined based on the position of the transverse partitions 52. Furthermore, when the lateral position of the transverse partitions 52 changes, the distance between them and the front wall of the housing 51 changes. Therefore, it is necessary to replace the longitudinal partitions 53 with those of corresponding lateral dimensions (i.e., select longitudinal partitions 53 with different front and rear widths) to ensure that the longitudinal partitions 53 can accommodate the changes in the distance between the transverse partitions 52 and the front wall of the housing 51.

[0072] 6. Multiple specifications and insertion depth adjustment of longitudinal diaphragm 53

[0073] The longitudinal partition 53 has various transverse dimensions (i.e., various longitudinal partitions 53 with different front and rear widths) to accommodate the installation and matching requirements of the transverse partition 52 at different transverse positions. Specifically, since the front end of the longitudinal partition 53 is connected to the front side wall of the housing 51 and the rear end is connected to the transverse partition 52, the transverse dimension of the longitudinal partition 53 must match the transverse spacing between the transverse partition 52 and the front side wall of the housing 51 to ensure that the front end of the longitudinal partition 53 can be inserted into the slot 55 on the front side wall of the housing 51 and the rear end can be inserted into the slot 55 on the transverse partition 52, thus achieving a sealed connection and fixation.

[0074] The slots 55 corresponding to the longitudinal partitions 53 (including the slots 55 on the front sidewall brackets 54 of the housing 51 and the slots 55 on the brackets 54 of the transverse partitions 52) have a preset depth in the transverse direction (i.e., the slots 55 have a certain extension length in the front-back direction, for example, 5cm to 20cm). This preset depth enables the slots 55 to have a size compensation function—the transverse dimension of the longitudinal partitions 53 does not need to be exactly equal to the transverse distance between the transverse partitions 52 and the front sidewall of the housing 51. As long as the size difference between the two is within the preset depth range of the slots 55, the longitudinal partitions 53 can compensate for this size difference by inserting into the corresponding slots 55 to different depths. When the transverse partition 52 moves to different positions in the lateral direction, the lateral distance between it and the front wall of the housing 51 changes accordingly. At this time, it is only necessary to select the specification with the closest width from the various lateral dimensions of the longitudinal partition 53, and compensate by changing the depth of the longitudinal partition 53 inserted into the corresponding slot 55. Matching installation can be achieved without having to specially prepare partitions with corresponding precision for each lateral distance, which greatly reduces the number of partition specifications and improves the adaptability of the device. The longitudinal partition 53 can be inserted into any position within the preset depth range of the corresponding slot 55, and a sealing fit can be formed with the slot 55 through the elastic sealing element.

[0075] It should be noted that when the longitudinal diaphragm 53 is inserted to different depths due to the adjustment of the transverse diaphragm 52, resulting in residual space (i.e., gap space) in the slot 55 that is not completely filled by the end of the longitudinal diaphragm 53, during the test, the mixed mud in the sedimentation zone may enter this gap space from the top of the slot 55 and remain there. However, since this gap space is a closed, still water zone, the entering mixed mud will not flow into adjacent sedimentation zones, nor will it affect the flow pattern of the main flow area of ​​the sedimentation zone or the rock debris settling process. After the test, when dimensional adjustments are required, the longitudinal diaphragm 53 is removed and the clamp 54 is taken off, and the inside of the slot 55 is cleaned and rinsed.

[0076] 7. Multi-level precipitation structure

[0077] There are at least two longitudinal partitions 53. The longitudinal partitions 53 are arranged laterally (front-to-back direction) in the sedimentation zone between the transverse partitions 52 and the front side wall of the tank 51, and are distributed sequentially longitudinally (left-to-right direction), dividing the sedimentation zone into multiple sedimentation zones in the longitudinal direction (left-to-right direction). The first sedimentation zone is the area between the leftmost longitudinal partition 53 and the left side wall of the tank 51. After that, each time you pass through a longitudinal partition 53 to the right, you enter the next sedimentation zone.

[0078] Each diaphragm 53 has a flow channel (i.e., the area between the diaphragm 53 and the top surface of the tank 51) to connect adjacent sedimentation zones, allowing the mixed slurry to flow from the previous sedimentation zone to the next. Along the longitudinal flow direction (i.e., from left to right), the lowest flow point of each flow channel decreases progressively—as shown in the image. Figure 2As shown, the top surface of the first longitudinal baffle 53 is higher than the second, the second is higher than the third, and so on. The top surface height of each longitudinal baffle 53 decreases stepwise along the longitudinal flow direction, thus creating a state where the flow point decreases stepwise. When the mixed mud flows from the previous sedimentation zone to the next sedimentation zone, it always passes through in a gentle overflow manner to avoid turbulence or water drop impact caused by excessive liquid level difference between adjacent sedimentation zones. This prevents the settled simulated rock debris from being resuspended due to water flow disturbance, ensuring the slurry-slag separation effect in each sedimentation zone.

[0079] 8. Slurry and residue outlet

[0080] A slurry outlet is provided on the right side wall of the tank 51 to discharge the mixed slurry after multi-stage sedimentation from the sedimentation unit 5. This slurry outlet is located at 1 / 5 of the height from the bottom plate of the tank 51. By setting the slurry outlet at a certain height from the bottom plate, it is ensured that the rock debris that has settled at the bottom of the sedimentation zone will not be carried out by the discharged slurry, while allowing the supernatant and suspended fine rock debris to be smoothly discharged from the sedimentation unit 5 and enter the subsequent separation unit 6.

[0081] (vi) Test lines and visual units 9

[0082] The front side of the housing 51 is equipped with transverse and longitudinal test lines (not shown in the figure). The transverse and longitudinal test lines interweave to form a calibration grid. The test lines are evenly distributed at calibration intervals (e.g., one line every 5 cm or 10 cm) to simulate the spatial position of rock debris in the sedimentation zone in real time. Through this test line grid, the operator can directly read the two-dimensional coordinates of rock debris particles at any location in the sedimentation zone, providing a spatial reference for subsequent velocity field analysis.

[0083] The vision unit 9 is positioned at a predetermined distance from the chamber 51 (e.g., 3-5m in front of the chamber 51), with its lens facing the front side of the chamber 51. It is used to continuously record images of the sedimentation of the simulated rock debris within the settling zone throughout the experiment. The vision unit 9 is preferably a high-speed camera with a sufficient frame rate (e.g., not less than 60fps) to capture the continuous sedimentation trajectory of the simulated rock debris. Combined with the transverse and longitudinal test lines set on the front side of the chamber 51, the real-time spatial position of each simulated rock debris particle can be determined in each frame recorded by the vision unit 9 using the grid marked by the test lines, thus providing accurate image data support for subsequent PIV (Particle Image Velocimetry) analysis.

[0084] (vii) Separation unit 6 and sensing unit 10

[0085] Separation unit 6 is located downstream of sedimentation unit 5. The mixed slurry discharged from sedimentation unit 5 (slurry carrying fine rock fragments that have not been settled after settling in the sedimentation zone) enters separation unit 6 for solid-liquid separation. Separation unit 6 includes a slurry-slag separation box 61, on the upper side of which a rock fragment isolation net 62 is placed to isolate and trap rock fragment particles in the mixed slurry, thereby achieving solid-liquid separation.

[0086] Specifically, the rock debris isolation net 62 has a mesh size of 0.5mm, which can effectively trap rock debris particles larger than 0.5mm, while allowing fine particles smaller than 0.5mm and mud liquid to pass through, thereby achieving the separation of rock debris and mud. The rock debris isolation net 62 is fixed to the slurry separation box 61 with eight bolts. Two handles are also fixed to the rock debris isolation net 62, making it convenient for operators to pick up and put down the rock debris isolation net 62 for collecting, weighing, and cleaning and replacing the net surface.

[0087] The sensing unit 10 is located at the bottom of the slurry-slag separation tank 61. In this embodiment, the sensing unit 10 includes pressure sensors respectively located at the four corners of the bottom of the slurry-slag separation tank 61, and each pressure sensor is connected to a data acquisition instrument. During the experiment, the mixed mud continuously enters the slurry-slag separation tank 61. The rock debris particles are intercepted by the rock debris isolation net 62 and accumulate on the net surface, while the mud liquid flows through the net surface into the bottom of the slurry-slag separation tank 61. The pressure sensors measure the total weight of all materials in the slurry-slag separation tank 61 (including the intercepted rock debris and the permeating mud) in real time and transmit the weight signal to the data acquisition instrument in real time for recording and storage.

[0088] Through the above structure, the separation unit 6 not only realizes the solid-liquid separation of the mixed slurry discharged from the sedimentation unit 5, but also, in conjunction with the pressure sensor and data acquisition instrument, realizes the real-time, continuous and accurate measurement of the total weight of the discharged mixed slurry, providing a reliable data basis for subsequent calculation of evaluation indicators such as total sedimentation efficiency, staged sedimentation efficiency and slurry-sludge carrying rate.

[0089] (viii) Setting the particle size and color of simulated rock debris

[0090] The simulated rock debris stored in the slag storage unit 3 has several different particle sizes (e.g., 1mm-2mm, 2mm-3mm, 3mm-4mm, 4mm-5mm, 5mm-6mm, 6mm-7mm, totaling 6 sizes), and the simulated rock debris of different sizes is colored differently (e.g., different particle sizes are colored green, blue, red, black, orange, and pink). Through the differentiation of colors, rock debris particles of different sizes can be quickly identified and distinguished in the sedimentation images recorded by the visual unit 9. This facilitates the separate statistical analysis of the sedimentation location, sedimentation velocity, and sedimentation efficiency of rock debris of different sizes in each sedimentation zone, thereby accurately evaluating the graded sedimentation effect of the sedimentation zone on rock debris of different sizes.

[0091] A test method for a test system simulating well drilling mud sedimentation, based on a test system simulating well drilling mud sedimentation, includes the following steps: S1 Preparation stage: Adjust the position and specifications of the transverse diaphragm 52 and the longitudinal diaphragm 53 according to a predetermined plan, determine the transverse dimensions, number of stages, and depth and longitudinal dimensions of each stage of the sedimentation zone, prepare simulated mud in mud preparation unit 1 and send the prepared simulated mud to mud storage unit 2, and load simulated rock cuttings into slag storage unit 3.

[0092] S2 test operation phase: Simulated mud and simulated rock debris are continuously supplied to mixing unit 4 at a predetermined flow rate. After mixing, they are gently fed into sedimentation unit 5 through inclined guide channel 8. The vision unit 9 is turned on to record the entire process. Separation unit 6 receives the mixed mud discharged from sedimentation unit 5.

[0093] S3 Data Processing and Evaluation Stage: Evaluation Index 1 (Graded Settling Velocity) The video recorded by visual unit 9 is decomposed frame by frame into photos. Combined with PIV technology, the displacement field of simulated rock debris in adjacent photos is converted into a velocity field to obtain the average settling velocity of each level of simulated rock debris in the sedimentation zone, which can evaluate the sedimentation effect of each level of simulated rock debris in the sedimentation zone.

[0094] Evaluation index 2 (total sedimentation efficiency) is calculated by weighing the weight m of the simulated rock slag received by the separation unit 6 and the weight M of the simulated rock slag released by the slag storage unit 3, and calculating (1-(m / M))×100% to evaluate the total simulated rock slag sedimentation efficiency in the sedimentation zone.

[0095] Evaluation index 3 (stage sedimentation efficiency): Weigh the simulated rock debris mi in each stage of the sedimentation zone, calculate (mi / M)×100%, and the sedimentation efficiency of the simulated rock debris in each stage of the sedimentation zone can be evaluated.

[0096] Evaluation index 4 (slurry carrying rate): The weight of simulated mud in separation unit 6 is obtained by subtracting the weight m of rock debris from the measured value of sensing unit 10. The value of (m / ml) × 100% is calculated as the slurry carrying rate, which can evaluate the efficiency of simulated mud carrying simulated rock debris out of the sedimentation zone.

[0097] S4 Multifactor Analysis Stage: Change the ratio of simulated mud, the flow rate of mixed mud, the flow rate of simulated rock debris, the lateral dimensions and number of stages of the mud sedimentation zone, and the depth and longitudinal dimensions of each stage. Repeat step S3 to obtain the influence of each factor on the sedimentation effect.

[0098] The simulated mud mix ratios in step S4 include the following five types, and the corresponding viscosities for each ratio are 1 mPa·s, 1.7 mPa·s, 5.5 mPa·s, 8.2 mPa·s, and 11 mPa·s, respectively:

[0099] The first type is entirely water;

[0100] The second type is salt water, prepared by adding 145g of industrial NaCl to every 1000ml of water;

[0101] The third type is a mixture of salt water and mucus, wherein the salt water ratio is 145g of industrial NaCl per 1000ml of water, and the mucus ratio is 0.1g of cellulose per 500ml of water, and the two are mixed in a 1:1 ratio.

[0102] The fourth type is a mixture of salt water and mucus, wherein the salt water is prepared by adding 145g of industrial NaCl to every 1000ml of water, and the mucus is prepared by adding 0.2g of cellulose to every 500ml of water, and the two are mixed in a 1:1 ratio.

[0103] The fifth type is a mixture of salt water and mucus, wherein the salt water is prepared by adding 145g of industrial NaCl to every 1000ml of water, and the mucus is prepared by adding 0.3g of cellulose to every 500ml of water, and the two are mixed in a 1:1 ratio.

[0104] The preparation processes for the five types of simulated mud are as follows:

[0105] When using the first mixing ratio, water is directly injected into the slurry storage unit 2;

[0106] When using the second ratio, water and industrial NaCl are added to the mixing tank 102 according to the ratio, and then stirred until the industrial NaCl is completely dissolved before being supplied to the slurry storage unit 2.

[0107] When using the third to fifth ratios, brine is prepared in one container 101 and slurry is prepared in another container 101 according to the ratio. Then, the two are fed into the mixing tank 102 and stirred and mixed. After mixing, the mixture is sent to the slurry storage unit 2.

[0108] In embodiments of the present invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0109] In the description of this invention, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "connected," "installed," and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, an integral connection, or a sliding connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal communication between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0110] The embodiments described herein are preferred embodiments of the present invention and are not intended to limit the scope of protection of the present invention. Therefore, all equivalent changes made based on the structure, shape, and principle of the present invention should be covered within the scope of protection of the present invention.

Claims

1. A test system for simulating well drilling mud sedimentation, characterized in that: It includes a mud preparation unit, a mud storage unit, a slag storage unit, a mixing unit, a sedimentation unit, and a separation unit; The mud preparation unit intermittently replenishes simulated mud to the mud storage unit; The slurry storage unit continuously supplies simulated slurry to the mixing unit; The slag storage unit supplies simulated rock slag to the mixing unit; The mixing unit mixes simulated rock debris with simulated mud. A flow regulation and monitoring unit is provided between the mud storage unit and the mixing unit. The capacity of the mud storage unit must at least cover all the needs of the mixing unit during the mud preparation period. The sedimentation unit includes a transparent box, horizontal partitions, and vertical partitions; The transverse partitions can be moved laterally to adjust the transverse dimensions of the sedimentation zone. The longitudinal partitions are located between the transverse partitions and the side walls of the tank. The longitudinal partitions can be moved longitudinally and their number can be varied to adjust the number of sedimentation zones and the longitudinal dimensions of each zone. The horizontal partitions are sealed and fixed to the box body, the longitudinal partitions are sealed to the horizontal partitions, and the transparent box body through connecting structures; The connecting structure includes a clamp and a locking element. The clamp spans the side wall of the corresponding component and has a slot on its inner side. When the locking element is locked, the clamp is pressed against the side wall of the corresponding component. The end of the transverse or longitudinal partition is inserted into the slot to form a sealed connection and fixation. When the locking element is released, the clamp can move in the corresponding direction. An inclined guide channel is provided between the sedimentation unit and the mixing unit to allow the mixed slurry to flow smoothly into the sedimentation unit; It also includes a vision unit for detecting sedimentation rate; A separation unit used to receive and separate the mixed slurry discharged from the sedimentation unit; A sensing unit used to measure the weight of the mixed mud discharged from the sedimentation unit.

2. The test system for simulating well drilling mud sedimentation according to claim 1, characterized in that: The longitudinal partition has various transverse dimensions. The slots corresponding to the longitudinal partition have a preset depth in the transverse direction. The longitudinal partition can form a sealed fit with the slot at any position within the preset depth range of the corresponding slot. By changing the insertion depth of the longitudinal partition of the same transverse dimension into the corresponding slot, the effective separation position of the longitudinal partition in the sedimentation zone in the transverse direction can be adjusted, so that the longitudinal partition of the same transverse dimension corresponds to multiple different transverse dimension levels.

3. The test system for simulating well drilling mud sedimentation according to claim 1, characterized in that: The number of longitudinal partitions is not less than two. After the longitudinal partitions are installed in the corresponding slots, they form a flow channel connecting the two sides of the longitudinal partition. Along the longitudinal flow direction, the lowest flow point of the flow channel decreases step by step.

4. The test system for simulating well drilling mud sedimentation according to claim 1, characterized in that: The mud preparation unit includes at least two containment tanks and one mixing tank. The containment tanks are connected to the mixing tank via conduits, and the conduits are equipped with flow regulation and monitoring units.

5. The test system for simulating well drilling mud sedimentation according to claim 4, characterized in that: The slurry storage unit and the mixing unit, as well as the mixing tank and the slurry storage unit, are connected by conduits. Each conduit is equipped with a water pump, and the inlet end of each conduit is equipped with a filter screen to filter impurities.

6. The test system for simulating well drilling mud sedimentation according to claim 1, characterized in that: The front side of the chamber is equipped with transverse and longitudinal measuring lines, which are arranged at calibrated distances to locate the position of simulated rock debris in real time. The vision unit is set at a preset distance on the front side of the chamber and is used to record the entire experimental process.

7. The test system for simulating well drilling mud sedimentation according to claim 1, characterized in that: The simulated rock slag in the slag storage unit has several specified particle sizes, and the simulated rock slag of different sizes has different colors.

8. A test method for a test system simulating drilling mud sedimentation, based on the test system for simulating drilling mud sedimentation as described in any one of claims 1-7, characterized in that, Includes the following steps: S1 Preparation Stage: Adjust the position and specifications of the transverse and longitudinal diaphragms according to the predetermined plan, determine the transverse dimensions, number of stages, and depth and longitudinal dimensions of each stage of the sedimentation zone, prepare simulated mud in the mud preparation unit and send the prepared simulated mud to the mud storage unit, and load simulated rock debris into the slag storage unit. S2 test operation phase: Simulated mud and simulated rock debris are continuously supplied to the mixing unit at a predetermined flow rate. After mixing, they are gently fed into the sedimentation unit through an inclined guide chute. The vision unit is activated to record the entire process. The separation unit receives the mixed mud discharged from the sedimentation unit. S3 Data Processing and Evaluation Phase: Evaluation index 1: Decompose the video recorded by the visual unit frame by frame into photos, and combine PIV technology to convert the displacement field of the simulated rock debris in adjacent photos into a velocity field to obtain the average settling velocity of each level of simulated rock debris in the sedimentation zone. Evaluation index 2: Calculate (1 - (m / M)) × 100% based on the weight m of the simulated rock debris received by the weighing and separation unit and the weight M of the simulated rock debris released by the slag storage unit. Evaluation index 3: Weigh the simulated rock debris weight mi in each stage of the sedimentation zone, and calculate (mi / M) × 100%; Evaluation index 4: Subtract the weight m of the rock debris from the measured value of the sensing unit to obtain the weight ml of the simulated mud in the separation unit, and calculate the mud carrying rate as (m / ml) × 100%. S4 Multifactor Analysis Stage: Change the ratio of simulated mud, the flow rate of mixed mud, the flow rate of simulated rock debris, the lateral dimensions and number of stages of the mud sedimentation zone, and the depth and longitudinal dimensions of each stage. Repeat step S3 to obtain the influence of each factor on the sedimentation effect.

9. The test method for a test system simulating well drilling mud sedimentation according to claim 8, characterized in that, The simulated mud mix ratios in step S4 include the following five, and the corresponding viscosities for each ratio are 1 mPa·s, 1.7 mPa·s, 5.5 mPa·s, 8.2 mPa·s, and 11 mPa·s, respectively: The first type is entirely water; The second type is salt water, prepared by adding 145g of industrial NaCl to every 1000ml of water; The third type is a mixture of salt water and mucus, wherein the salt water ratio is 145g of industrial NaCl per 1000ml of water, and the mucus ratio is 0.1g of cellulose per 500ml of water, and the two are mixed in a 1:1 ratio. The fourth type is a mixture of salt water and mucus, wherein the salt water is prepared by adding 145g of industrial NaCl to every 1000ml of water, and the mucus is prepared by adding 0.2g of cellulose to every 500ml of water, and the two are mixed in a 1:1 ratio. The fifth type is a mixture of salt water and mucus, wherein the salt water is prepared by adding 145g of industrial NaCl to every 1000ml of water, and the mucus is prepared by adding 0.3g of cellulose to every 500ml of water, and the two are mixed in a 1:1 ratio.

10. The test method for a test system simulating well drilling mud sedimentation according to claim 9, characterized in that, The preparation processes for the five types of simulated mud are as follows: When using the first mixing ratio, water is directly added to the slurry storage unit; When using the second ratio, water and industrial NaCl are added to the mixing tank according to the ratio, and then stirred until the industrial NaCl is completely dissolved before being supplied to the slurry storage unit. When using the third to fifth ratios, brine is prepared in one container and slurry is prepared in another container according to the ratio. Then, the two are fed into the mixing tank and stirred and mixed according to the ratio. After mixing, the mixture is sent to the slurry storage unit.

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