A method for reducing pressure in high-pressure pipelines

Abstract

This invention discloses a high-pressure pipeline pressure reduction method, relating to the field of backfill mining. After the slurry enters the upper conical tube of the tank, it forms a high-speed jet, driving the turntable to rotate and generating shaft power. Finally, a damper dissipates the slurry's potential energy to achieve pressure reduction. This method offers good pressure reduction, is simple to implement, and low in cost. The installation location can be determined according to project needs, ensuring reasonable pipeline pressure. The method is highly adaptable, requiring no specific slurry filling level in the pipeline; both full and partially filled slurry levels do not affect the pressure reduction effect. Furthermore, the pipeline remains vertical, preventing slurry accumulation and solidification that could block the pipeline.

Description

Technical Field

[0001] This invention relates to the field of backfill mining, and more particularly to a method for reducing pressure in high-pressure pipelines. Background Technology

[0002] Modern industrial development is inseparable from various raw materials, and mining is one of the most direct ways to obtain them. After mining is completed, to prevent mine collapses that could cause environmental damage, property loss, and loss of life, the mine is often filled in to prevent such incidents. During deep well backfilling, as the mine filling slurry is transported downwards through pipelines or other channels, the elevation difference increases, and the fluid velocity also increases. Since pipeline resistance is relatively low, excessive elevation differences will cause excessive pipeline pressure, adversely affecting the safety of the pipeline system, pipeline wear, and operating costs.

[0003] Currently, pressure reduction methods for filling pipelines mainly include pressure reducing tanks, variable diameter pipe transportation, zigzag pipe transportation, and spiral pipe resistance-increasing and pressure-regulating structures. However, these methods require more basic conditions, the pipelines are long and complex, the costs are high, and the equipment maintenance is extensive. Summary of the Invention

[0004] Therefore, the present invention provides a high-pressure pipeline pressure reduction method that is simple to implement and low in cost, which can solve the technical problem of backfilling in deep well mining.

[0005] This invention includes the following steps:

[0006] Step 1: Start the slurry valve to inject slurry into the inlet pipeline. Due to gravity, the slurry flows from top to bottom.

[0007] Step 2: Connect the upper conical pipe of the box to the lower end of the inlet pipe. The slurry flows through the upper conical pipe of the upper box and is sprayed out at a speed of v.

[0008] Step 3: Install the bowl of the turntable under the conical tube at the top of the box to receive the impact of the slurry and rotate along the center of the rotating shaft;

[0009] Step 4: Fix the damper to the shaft. The damper speed should always be consistent with the shaft speed. The shaft speed should be gradually increased until it reaches the rated speed n of the damper and remains constant. The damper consumes the shaft power generated by the shaft.

[0010] Step 5: Install the turntable inside the tank. After the slurry does work, it flows out of the bowl at a very low speed v2 and splashes onto the wall of the tank. Under the action of gravity, it flows downward and flows back to the outlet pipe through the inverted conical structure at the bottom of the tank.

[0011] In the above-mentioned high-pressure pipeline pressure reduction method, the method for determining the slurry injection velocity v is as follows: the outlet of the conical tube at the upper end of the tank is at atmospheric pressure, where the pressure potential energy of the slurry is entirely converted into injection kinetic energy. The formula for the slurry injection velocity v is as follows:

[0012]

[0013] In the formula: v is the injection velocity of the slurry, in m / s;

[0014] P is the inlet pressure of the conical tube at the top of the box, in Pa;

[0015] ρ is the slurry density, in kg / m³ 3 ;

[0016] The loss coefficient of the upper conical tube of the housing is typically between 0.02 and 0.1.

[0017] In the above-mentioned high-pressure pipeline pressure reduction method, the bowl receives high-speed impact from the slurry. When the shaft speed reaches speed n, the force formula of the bowl is as follows:

[0018]

[0019] In the formula: F is the force acting on the bowl, in N;

[0020] m represents the mass of the slurry entering the bowl, in kg;

[0021] t is the time in seconds (s) during which mass m of slurry does work in the bowl.

[0022] L2 is the distance from the center line of the bowl to the center line of the rotating shaft, in meters;

[0023] n is the rated speed of the damper, in r / min;

[0024] v2 is the velocity of the slurry flowing out of the bowl, in m / s.

[0025] In the above-mentioned high-pressure pipeline pressure reduction method, the damper rotation speed is consistent with the shaft rotation speed. When the damper reaches the rated speed n, the damper power is taken as a 1.5 times margin, as shown in the following formula:

[0026] P = 1.5 × FL²πn / 30

[0027] In the formula: P is the damper power, in W.

[0028] The beneficial technical effects of this invention are:

[0029] 1. The high-pressure pipeline pressure reduction method has a good pressure reduction effect. The installation position of the device can be determined according to the project needs to ensure that the pressure of the filling pipeline is reasonable.

[0030] 2. The high-pressure pipeline pressure reduction method is highly adaptable and has no requirements on the full state of the slurry in the pipeline. The pipeline can be full of slurry or not, and neither will affect the pressure reduction effect.

[0031] 3. The high-pressure pipeline pressure reduction method eliminates the need for complex structures such as pressure reducing tanks, variable diameter pipes for transportation, return pipes for transportation, and spiral pipes for resistance increase. It does not change the original main structure of the filling pipeline, and only requires cutting off a small part of the pipeline. It is simple to implement and low in cost. Moreover, the pipeline is always in a vertical state, which avoids the slurry from accumulating, solidifying and blocking the pipeline. Attached Figure Description

[0032] Figure 1 This is a front view illustrating the principle of the method of the present invention;

[0033] Figure 2 This is a side view illustrating the principle of the method of the present invention;

[0034] Figure 3 This is a cross-sectional view of the bowl.

[0035] The components in the diagram are labeled as follows: 1-Inlet pipe, 2-Box, 3-Bowl, 4-Turntable, 5-Air inlet, 6-Shaft, 7-Damper. Detailed Implementation

[0036] The present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0037] Specific implementation method one: as follows Figure 1 and Figure 2 As shown, this embodiment provides a high-pressure pipeline pressure reduction method, which is implemented through the following steps:

[0038] Step 1: Start the slurry valve and inject the slurry into inlet pipe 1. Due to gravity, the slurry flows from top to bottom.

[0039] Step 2: Connect the upper conical tube of the box 2 to the lower end of the inlet pipe 1. The slurry flows through the upper conical tube of the box 2 and is sprayed out at a speed v.

[0040] Step 3: Install the bowl 3 of turntable 4 under the upper conical tube of box 2 to receive the impact of slurry and rotate along the rotation center of shaft 6;

[0041] Step 4: Fix the damper 7 to the shaft 6. The rotation speed of the damper 7 is always consistent with the rotation speed of the shaft 6. The rotation speed of the shaft 6 gradually increases until it reaches the rated speed n of the damper 7 and remains constant. The damper 7 consumes the shaft power generated by the shaft 6.

[0042] Step 5: Install the turntable 4 inside the box 2. After the slurry does work, it flows out of the bowl 3 at a very low speed v2 and splashes onto the wall of the box 2. Under the action of gravity, it flows downward and flows back to the outlet pipe through the inverted cone structure at the lower end of the box 2.

[0043] This embodiment converts the gravitational potential energy of the slurry into rotational kinetic energy, that is, transforms a dispersed energy into a concentrated energy that is easy to handle, and then consumes it by the damper. This method effectively achieves pressure reduction in high-pressure pipelines with good pressure reduction effect. The equipment installation position can be determined according to the project needs. After the pipeline pressure is reduced, the low-speed slurry is recovered by the tank to ensure that the filling pipeline pressure is reasonable.

[0044] Specific implementation method two: such as Figure 1 and Figure 2 As shown, this embodiment further defines step two of the specific embodiment one. In this embodiment, the inlet diameter of the upper conical tube of the box 2 is equal to the diameter of the inlet pipe 1, the distance from the center line of the upper conical tube of the box 2 to the center line of the rotating shaft 6 is L1, and an air inlet 5 is opened on the top cover of the box 2 to connect with the atmosphere. The method for determining the slurry injection speed v is as follows: the outlet of the upper conical tube of the box 2 is at atmospheric pressure, and the pressure potential energy of the slurry here is completely converted into injection kinetic energy. The formula for the slurry injection speed v is as follows:

[0045]

[0046] In the formula: v is the injection velocity of the slurry, in m / s;

[0047] P is the inlet pressure of the conical tube at the upper end of box 2, in Pa;

[0048] ρ is the slurry density, in kg / m³ 3 ;

[0049] The loss coefficient of the upper conical tube of box 2 is usually between 0.02 and 0.1.

[0050] This embodiment converts the gravitational potential energy of the slurry into the kinetic energy of the jet. This method has good adaptability and does not require the slurry to be in a full pipe state. The inlet pipe 1 can be full of slurry or not full of slurry. The corresponding jet slurry can be continuous or intermittent.

[0051] Specific implementation method three: such as Figures 1 to 3As shown, this embodiment further defines step three of the specific embodiment one. In this embodiment, the bowl 3 has a semi-circular structure with a triangular structure in the center. The top of the triangle is rounded, and the bottom of the triangle smoothly transitions to the bottom of the bowl 3. The inner and outer surfaces of the bowl 3 have a highly rough anti-abrasion coating. N bowls 3 of the same shape are evenly distributed on the turntable 4, and the number of N is 19 to 21. The bowl 3 is subjected to high-speed impact from the slurry. When the rotation speed of the rotating shaft 6 reaches speed n, the force formula of the bowl 3 is as follows:

[0052]

[0053] In the formula: F is the force acting on bowl 3, in N;

[0054] m represents the mass of the slurry entering bowl 3, in kg;

[0055] t is the time in seconds (s) for mass m of slurry to do work in bowl 3.

[0056] L2 is the distance from the center line of bowl 3 to the center line of rotating shaft 6, and L2 = L1, in meters;

[0057] n is the rated speed of damper 7, in r / min;

[0058] v2 is the velocity of the slurry flowing out of bowl 3, in m / s.

[0059] This embodiment converts the kinetic energy of the slurry jet into a force on the bowl 3 based on the momentum theorem, thus realizing the conversion of the slurry's kinetic energy. At the same time, due to the extremely rough surface of the bowl 3, the kinetic energy of the slurry will not only generate a thrust on the bowl 3, but will also generate heat energy due to friction, further consuming the slurry's energy. The generated heat is then carried away by the slurry.

[0060] Specific implementation method four: such as Figure 1 and Figure 2 As shown, this embodiment further defines step four of the specific embodiment one. In this embodiment, the damper 7 is a damping device that can consume rotational kinetic energy. Its power is large enough to automatically adjust according to the power of the rotating shaft 6, and it can operate stably at the rated speed n. The speed of the damper 7 is consistent with the speed of the rotating shaft 6. When the damper 7 reaches the rated speed n, the power of the damper 7 is taken as 1.5 times the margin. The formula is as follows:

[0061] P = 1.5 × FL²πn / 30

[0062] In the formula: P is the power of the damper, in W.

[0063] In this embodiment, the axial power generated by the force on the bowl 3 is transmitted to the damper 7 and consumed by the damper 7, thereby achieving the pressure reduction effect of the pipeline. This method eliminates the need for complex structures such as pressure reducing tank, variable diameter pipe conveying, return pipe conveying, and spiral pipe resistance increase, making it simple to implement and low in cost. Moreover, the pipeline is always in a vertical state, avoiding the accumulation and solidification of slurry that may block the pipeline.

[0064] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. However, these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A high-pressure pipeline pressure relief method, characterized by the following steps: Step 1: Start the slurry valve and fill the slurry into the inlet pipeline (1); Step 2: Connect the upper end cone pipe of the box (2) with the lower end of the inlet pipeline (1), and the slurry is sprayed out at a speed v after flowing through the upper end cone pipe of the box (2); Step 3: Install the bowl (3) of the rotating disc (4) below the upper end cone pipe of the box (2) to accept the impact of the slurry and rotate along the rotating center of the rotating shaft (6); Step 4: Fix the damper (7) with the rotating shaft (6), the rotating speed of the damper (7) always keeps consistent with the rotating speed of the rotating shaft (6), the rotating speed of the rotating shaft (6) gradually increases until it reaches the rated rotating speed n of the damper (7) and remains unchanged, and the damper (7) consumes the shaft power generated by the rotating shaft (6); Step 5: Install the rotating disc (4) inside the box (2), the slurry flows out of the bowl (3) and splashes to the wall of the box (2) at a very low speed v2 after doing work, and flows downward under the action of gravity and reflows back to the outlet pipeline through the inverted cone structure at the lower end of the box (2); The bowl (3) is a semicircular structure, the center of the bowl (3) has a triangular structure, the top of the triangle is rounded, the bottom of the triangle is smoothly transitioned with the bottom of the bowl (3), and the inner and outer surfaces of the bowl (3) have an anti-abrasion coating with a large roughness; N identical bowls (3) are evenly distributed on the rotating disc (4), and the number N is 19 to 21; The rotating speed of the damper (7) keeps consistent with the rotating speed of the rotating shaft (6), when the damper (7) reaches the rated rotating speed n, the power of the damper (7) is calculated by the following formula with a 1.5 times margin: P = 1.5 × FL2πn / 30 In the formula, P is the power of the damper (7) with the unit of W.

2. The method of claim 1, wherein: The determination method of the slurry spraying speed v is that the outlet of the upper end cone pipe of the box (2) is atmospheric pressure, the pressure potential energy of the slurry at this point is completely converted into kinetic energy, and the formula of the slurry spraying speed v is as follows: In the formula, v is the spraying speed of the slurry with the unit of m / s; P is the inlet pressure of the upper end cone pipe of the box (2) with the unit of Pa; p is the density of the slurry in kg / m 3 ; The loss coefficient of the conical tube at the upper end of the tank (2) is usually taken as 0.02 to 0.

1.

3. The method of claim 1, wherein: When the rotating speed of the rotating shaft (6) reaches the rotating speed n, the bowl (3) is impacted by the high-speed slurry, and the force formula of the bowl (3) is as follows: In the formula, F is the force acting on the bowl (3) with the unit of N; m is the mass of the slurry entering the bowl (3) with the unit of kg; t is the time for the mass m of the slurry to do work in the bowl (3) with the unit of s; L2 is the distance between the center line of the bowl (3) and the center line of the rotating shaft (6) with the unit of m; n is the rated rotating speed of the damper (7) with the unit of r / min; v2 is the speed of the slurry flowing out of the bowl (3) with the unit of m / s.

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