Fluidized bed reactor material level measuring device

Abstract

The invention provides a fluidized bed reactor material level measuring device, and belongs to the technical field of chemical instrument measurement, the fluidized bed reactor material level measuring device comprises a connecting flange connected to a reactor, the mounting position of the connecting flange corresponds to the material level detection position of the reactor, and the connecting flange is provided with a connecting channel along the axis direction; and the pressure guide pipe is nested on the connecting channel, a pressure guide channel is arranged in the pressure guide pipe, two ends of the pressure guide pipe are respectively a first port and a second port, the first port is positioned in the reactor, and the second port is positioned outside the reactor and is connected with the positive pressure side of the pressure difference transmitter. The pressure at the material level detection position of the reactor is led out of the reactor through the pressure leading pipe, operation is easy and convenient, the pressure leading pipe is made of hard materials, the first port located at the material level detection position cannot be damaged due to friction impact of polymer particles, the service life is long, and detection data are accurate as well.

Description

Technical Field

[0001] The invention belongs to the technical field of chemical instrument measurement and relates to a measuring device, in particular to a material level measuring device for a fluidized bed reactor. Background Art

[0002] The fluidized bed reactor contains a mixed polymer of propylene and ethylene, where the two polymerize to form a binary copolymer. Upon entering the reactor, the polymer flows downward and comes into contact with an upward-flowing fluidizing gas stream, which is injected via a fluidizing compressor through a notched conical tray at the bottom of the reactor and a distribution plate. The fluidizing gas stream suspends the copolymer at the bottom of the fluidized bed reactor, maintaining a fluidized state. The reactor level is automatically controlled by a level controller, which derives its setpoint from the pressure control output. Reaction pressure control is primarily achieved by adjusting the polymer level in the reactor.

[0003] In the existing technology, the reactor has three level meters, two of which feed level signals into the DCS control system, and one feeds into the SIS system for interlocking. The level meters use the differential pressure principle for measurement, and the process package calculates the level meter range differential pressure based on the full-scale suspension of the powder. The high-pressure side of the level meter uses an insert-type flange diaphragm to measure pressure. However, this insert-type flange diaphragm is located inside the reactor during testing. When the fluidizing gas carries the polymer around the bottom of the reactor, it causes the polymer particles to rub against the inner wall of the reactor. At this time, the diaphragm in the diaphragm is also impacted by the polymer particles. After a period of time, the diaphragm is damaged by the impact, making it impossible to measure the reactor level properly. Summary of the Invention

[0004] The purpose of the present invention is to address the above problems in the existing technology and to propose a fluidized bed reactor level measuring device that can operate stably for a long period of time and obtain reliable data.

[0005] The object of the present invention can be achieved by the following technical solutions: A fluidized bed reactor level measuring device comprising:

[0006] A connecting flange is connected to the reactor, and the installation position of the connecting flange corresponds to the material level detection position of the reactor, wherein the connecting flange is provided with a connecting channel along the axial direction thereof;

[0007] The pressure-inducing pipe is nested in the connecting channel, and a pressure-inducing channel is provided in the pressure-inducing pipe. The two ends of the pressure-inducing pipe are respectively a first port and a second port. The first port is located inside the reactor, and the second port is located outside the reactor and is connected to the positive pressure side of the differential pressure transmitter. The first port of the pressure-inducing pipe is provided with an arc-shaped anti-blocking portion, and the anti-blocking portion is bent along the entry direction of the fluidizing gas in the reactor.

[0008] In the above-mentioned fluidized bed reactor material level measuring device, the bending direction of the anti-blocking portion is consistent with the rotation direction of the polymer in the reactor.

[0009] In the above-mentioned fluidized bed reactor material level measuring device, the length of the pressure-inducing tube extending into the interior of the reactor is not less than 20 cm.

[0010] In the above-mentioned fluidized bed reactor level measuring device, the pressure-inducing tube and the connecting flange are fixed by welding, and the two ends of the connecting flange along the axial direction are respectively the first end face and the second end face, wherein the first end face and the second end face are respectively welded and fixed to the outer tube wall of the pressure-inducing tube.

[0011] In the above-mentioned fluidized bed reactor level measuring device, an external tube is connected to the pressure-inducing tube near the second port, and a backflush channel is provided in the external tube, and the backflush channel is connected to the pressure-inducing channel, wherein the backflush channel is used to pass backflush gas, and the flow direction of the backflush gas passed into the backflush channel is opposite to the flow direction of the pressure-inducing gas in the pressure-inducing channel.

[0012] In the above-mentioned fluidized bed reactor material level measuring device, the pressure-introducing pipe and the external pipe are connected via a three-way valve.

[0013] In the above-mentioned fluidized bed reactor level measuring device, the backflush gas in the backflush channel on the external pipe operates in a continuous low-flow output or an intermittent high-flow output. A solenoid valve is provided on the external pipe to realize the continuous output and intermittent output of the backflush gas and control the output flow of the backflush gas.

[0014] In the above-mentioned fluidized bed reactor level measuring device, a straight-through root valve is provided on the pressure-guiding pipe between the external pipe and the second end face of the connecting flange, and an air inlet end and an air outlet end are provided on the straight-through root valve, wherein both the air inlet end and the air outlet end are connected to the pressure-guiding pipe, or the air inlet end is connected to the pressure-guiding pipe, and the air outlet end is connected to the three-way valve.

[0015] In the above-mentioned fluidized bed reactor level measuring device, a straight-through root valve is arranged between the second port of the pressure-inducing pipe and the external pipe, and an air inlet end and an air outlet end are arranged on the straight-through root valve, wherein the air inlet end and the air outlet end are both connected to the pressure-inducing pipe, or the air inlet end is connected to the three-way valve, and the air outlet end is connected to the pressure-inducing pipe.

[0016] In the above-mentioned fluidized bed reactor material level measuring device, the connecting flange is arranged in a stepped shape, including a connecting portion and a positioning portion, and the first end face is arranged on the connecting portion, and the second end face is arranged on the positioning portion.

[0017] Compared with the prior art, the present invention has the following beneficial effects:

[0018] (1) The present invention provides a fluidized bed reactor level measuring device, which draws the pressure at the reactor level detection position from the reactor through a pressure-inducing pipe and leads it to the positive pressure side of a differential pressure transmitter, thereby measuring the pressure at the position. The operation is simple and convenient, and the pressure-inducing pipe is made of a hard material. The first port at the level detection position will not be damaged by the friction and impact of polymer particles, has a long service life, and the detection data is also relatively accurate.

[0019] (2) The anti-blocking portion is arranged in an arc shape and is bent in the direction of the fluidizing gas entering the reactor, so that the bending direction of the anti-blocking portion is consistent with the rotation direction of the polymer in the reactor. This arrangement can greatly reduce the risk of polymer blockage at the first port of the pressure-inducing pipe, ensure the smooth flow of the pressure-inducing pipe, and thus improve the reliability of the pressure data at the material level detection position.

[0020] (3) Extending the pressure-supply pipe at least 20 cm into the reactor helps ensure that the differential pressure transmitter can obtain data that is closer to the actual operating conditions. This is mainly because the flow state of the polymer near the inner wall of the reactor may be different from that in the center of the reactor, including the possible existence of boundary layer effects, which may lead to inaccurate measurement results. In addition, a longer pressure-supply pipe can reduce the risk of blockage caused by polymer precipitation, crystallization, or accumulation of other solid particles.

[0021] (4) By providing a backflush channel, the accumulation of polymer at the first port of the pressure-inducing pipe is further prevented, thereby ensuring the smooth flow of the pressure-inducing pipe. In addition, the backflush gas in this embodiment is propylene. The reason for choosing propylene is that the polymer in the reactor is a mixture of propylene and ethylene, and the introduction of propylene will not cause contamination of the mixture.

[0022] (5) By setting a three-way valve, the flow direction or flow ratio of the fluid between different pipelines can be controlled. In this embodiment, the three-way valve will not affect the process flow of material level pressure measurement when introducing back-blowing gas, and it helps to keep the inside of the pressure-inducing channel clean, reduce the risk of blockage, and extend the service life of the pressure-inducing pipe.

[0023] (6) Through the solenoid valve, regular atmospheric back-blowing operation is realized to ensure that the pressure lead pipe is always in a smooth state, thus ensuring the stability and accuracy of the material level measurement.

[0024] (7) The connecting flange is set into a stepped shape to facilitate the precise installation of the connecting flange on the reactor, and effectively control the relative length of the pressure-inducing pipe extending into the reactor, thereby improving the reliability of material level detection. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a structural schematic diagram of a material level measuring device for a fluidized bed reactor of the present invention.

[0026] In the figure, 10, connecting flange; 11, first end face; 12, second end face; 13, connecting portion; 14, positioning portion;

[0027] 20. Pressure-inducing pipe; 21. Pressure-inducing channel; 22. First port; 23. Second port; 24. Anti-blocking portion;

[0028] 30. External pipe; 31. Backflush channel;

[0029] 40. Three-way valve;

[0030] 50. Straight-through root valve. DETAILED DESCRIPTION

[0031] The following are specific embodiments of the present invention and the accompanying drawings to further describe the technical solutions of the present invention, but the present invention is not limited to these embodiments.

[0032] It should be noted that all directional indications in the embodiments of the present invention (such as up, down, left, right, front, back, etc.) are only used to explain the relative position relationship, movement status, etc. between the various components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0033] like Figure 1 As shown, the present invention provides a fluidized bed reactor level measuring device, comprising:

[0034] A connecting flange 10 is connected to the reactor, and the installation position of the connecting flange 10 corresponds to the material level detection position of the reactor, wherein the connecting flange 10 is provided with a connecting channel along its axial direction;

[0035] The pressure-inducing tube 20 is nested in the connecting channel, and a pressure-inducing channel 21 is provided in the pressure-inducing tube 20. The two ends of the pressure-inducing tube 20 are respectively a first port 22 and a second port 23. The first port 22 is located inside the reactor, and the second port 23 is located outside the reactor and is connected to the positive pressure side of the differential pressure transmitter.

[0036] It is worth mentioning that the first port 22 of the pressure-inducing tube 20 corresponds to the material level detection position of the reactor, and the second port 23 of the pressure-inducing tube 20 is connected to the positive pressure side of the differential pressure transmitter. Thus, the pressure to be measured at the material level detection position on the reactor is led to the positive pressure side of the differential pressure transmitter through the pressure-inducing tube 20. The pressure at the material level detection position of the reactor can be measured by the difference between the positive pressure side and the negative pressure side of the differential pressure transmitter.

[0037] The present invention provides a fluidized bed reactor level measuring device, which draws the pressure at the reactor's level detection position from the reactor through a pressure-inducing pipe 20 and leads it to the positive pressure side of a differential pressure transmitter, thereby measuring the pressure at that position. The operation is simple and convenient, and the pressure-inducing pipe 20 is made of a hard material. The first port 22 located at the level detection position will not be damaged by the friction and impact of polymer particles, has a long service life, and the detection data is also relatively accurate.

[0038] It is further pointed out that an anti-blocking portion 24 is provided at the first port 22 of the pressure-inducing tube 20 , and the anti-blocking portion 24 is integrally provided with the pressure-inducing tube 20 .

[0039] It is worth mentioning that, since the polymer in the reactor continuously rotates and rolls under the action of the fluidizing gas, it hits the first port 22 of the pressure-inducing tube 20. At the same time, the polymer on the inner wall of the reactor slows down its rotation speed due to viscosity, which makes the first port 22 of the pressure-inducing tube 20 easily blocked by the viscous polymer. By providing the anti-blocking portion 24, the accumulation of polymer can be avoided, the smooth flow of the pressure-inducing tube 20 can be ensured, and the reliability of the pressure data at the material level detection position can be further improved.

[0040] Furthermore, the anti-blocking portion 24 is arcuate and bends toward the fluidizing gas entering the reactor, aligning its curvature with the direction of polymer rotation in the reactor. This configuration significantly reduces the risk of polymer blockage at the first port 22 of the pressure-inducing pipe 20, ensuring unobstructed flow of the pressure-inducing pipe 20 and improving the reliability of pressure data at the material level detection location.

[0041] It is further pointed out that the length of the pressure-inducing pipe 20 extending into the interior of the reactor is not less than 20 cm.

[0042] In this embodiment, extending the pressure-supply line 20 at least 20 cm into the reactor helps ensure that the differential pressure transmitter acquires data that more closely reflects actual operating conditions. This is primarily because the polymer flow conditions near the reactor's inner wall may differ from those in the reactor's center, including the potential for boundary layer effects, leading to inaccurate measurement results. Furthermore, a longer pressure-supply line 20 reduces the risk of blockage due to polymer precipitation, crystallization, or other solid particle accumulation.

[0043] It is further pointed out that the pressure-inducing tube 20 is fixed to the connecting flange 10 by welding, and the two ends of the connecting flange 10 along the axial direction are respectively a first end face 11 and a second end face 12, wherein the first end face 11 and the second end face 12 are respectively welded and fixed to the outer tube wall of the pressure-inducing tube 20.

[0044] It is worth mentioning that the two ends of the connecting flange 10 are respectively welded to the outer wall of the pressure-inducing pipe 20 to form a stable overall structure, which increases the connection strength between the connecting flange 10 and the pressure-inducing pipe 20 and can adapt to more stringent working environments. In addition, the pressure-inducing pipe 20 is welded to the connecting flange 10 to further control the length of the pressure-inducing pipe 20 extending into the reactor.

[0045] Preferably, an external tube 30 is connected to the pressure-inducing tube 20 near the second port 23, and a backflush channel 31 is provided in the external tube 30, and the backflush channel 31 is connected to the pressure-inducing channel 21, wherein the backflush channel 31 is used to pass backflush gas, and the flow direction of the backflush gas passed into the backflush channel 31 is opposite to the flow direction of the pressure-inducing gas in the pressure-inducing channel 21.

[0046] In this embodiment, the backflush channel 31 is provided to further prevent polymer accumulation and blockage at the first port 22 of the pressure-inducing pipe 20, thereby ensuring the smooth flow of the pressure-inducing pipe 20. Furthermore, the backflush gas in this embodiment is propylene. This is chosen because the polymer in the reactor is a mixture of propylene and ethylene, and the introduction of propylene will not contaminate the mixture.

[0047] It is further pointed out that the pressure-introducing pipe 20 and the external pipe 30 are connected via a three-way valve 40 .

[0048] In this embodiment, by setting a three-way valve 40, the flow direction or flow ratio of the fluid between different pipelines can be controlled. In this embodiment, the three-way valve 40 will not affect the process flow of the material level pressure measurement when introducing back-blowing gas, and it helps to keep the inside of the pressure-inducing channel 21 clean, reduce the risk of blockage, and extend the service life of the pressure-inducing tube 20.

[0049] It is further pointed out that the operation mode of the back-blowing gas in the back-blowing channel 31 on the external pipe 30 is continuous small flow output or intermittent large flow output, wherein a solenoid valve is provided on the external pipe 30, through which the continuous output and intermittent output of the back-blowing gas are realized, and the output flow rate of the back-blowing gas is controlled.

[0050] In this embodiment, a regular atmospheric back-flushing operation is implemented through the solenoid valve to ensure that the pressure-inducing pipe 20 is always in an unobstructed state, thereby ensuring the stability and accuracy of the material level measurement.

[0051] Preferably, a straight-through root valve 50 is provided on the pressure-guiding pipe 20 between the external pipe 30 and the second end face 12 of the connecting flange 10, and an air inlet end and an air outlet end are provided on the straight-through root valve 50, wherein both the air inlet end and the air outlet end are connected to the pressure-guiding pipe 20, or the air inlet end is connected to the pressure-guiding pipe 20, and the air outlet end is connected to the three-way valve 40.

[0052] In this embodiment, the connection or blocking between the pressure-inducing channel 21 and the differential pressure transmitter is achieved through the straight-through root valve 50. The straight-through root valve in this embodiment can be a needle valve, a straight-through root valve, a stop-type root valve, or a ball valve.

[0053] It is worth mentioning that the straight-through root valve 50 can also be arranged between the second port 23 of the pressure-leading pipe 20 and the external pipe 30, wherein the air inlet end and the air outlet end are both connected to the pressure-leading pipe 20, or the air inlet end is connected to the three-way valve 40, and the air outlet end is connected to the pressure-leading pipe 20.

[0054] Preferably, the connecting flange 10 is arranged in a stepped shape, including a connecting portion 13 and a positioning portion 14 , wherein the first end surface 11 is arranged on the connecting portion 13 , and the second end surface 12 is arranged on the positioning portion 14 .

[0055] In this embodiment, the connecting flange 10 is configured in a stepped shape, which facilitates accurate installation of the connecting flange 10 on the reactor and effectively controls the relative length of the pressure-inducing pipe 20 extending into the reactor, thereby improving the reliability of material level detection.

[0056] It is worth mentioning that the connection portion 13 and the reactor can be connected via threads.

[0057] It should be noted that, in the present invention, descriptions such as "first", "second", "one", etc. are only used for descriptive purposes, and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "multiple" is at least two, such as two, three, etc., unless otherwise clearly defined. The terms "connected", "fixed", etc. should be understood in a broad sense. For example, "fixed" can be a fixed connection, a detachable connection, or an integral whole; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to the specific circumstances.

[0058] In addition, the technical solutions between the various embodiments of the present invention can be combined with each other, but it must be based on the fact that ordinary technicians in this field can implement it. When the combination of technical solutions is mutually contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0059] The specific embodiments described herein are merely illustrative of the spirit of the present invention. Persons skilled in the art may make various modifications, additions, or substitutions to the described specific embodiments without departing from the spirit of the present invention or exceeding the scope of the appended claims.

Claims

1. A fluidized bed reactor level measuring device, characterized in that: include: A connecting flange is connected to the reactor, and the installation position of the connecting flange corresponds to the material level detection position of the reactor, wherein the connecting flange is provided with a connecting channel along the axial direction thereof; The pressure-inducing pipe is nested in the connecting channel, and a pressure-inducing channel is provided in the pressure-inducing pipe. The two ends of the pressure-inducing pipe are respectively a first port and a second port. The first port is located inside the reactor, and the second port is located outside the reactor and is connected to the positive pressure side of the differential pressure transmitter. The first port of the pressure-inducing pipe is provided with an arc-shaped anti-blocking portion, and the anti-blocking portion is bent along the entry direction of the fluidizing gas in the reactor.

2. A fluidized bed reactor level measuring device according to claim 1, characterized in that: The bending direction of the anti-blocking part is consistent with the rotation direction of the polymer in the reactor.

3. The fluidized bed reactor level measuring device according to claim 1, characterized in that: The length of the pressure-inducing pipe extending into the interior of the reactor is not less than 20 cm.

4. A fluidized bed reactor level measuring device according to claim 1, characterized in that: The pressure-inducing tube and the connecting flange are fixed by welding, and the two ends of the connecting flange along the axial direction are respectively a first end face and a second end face, wherein the first end face and the second end face are respectively welded and fixed to the outer tube wall of the pressure-inducing tube.

5. A fluidized bed reactor level measuring device according to any one of claims 1 to 4, characterized in that: An external tube is connected to the pressure-inducing tube near the second port, and a backflush channel is provided in the external tube, and the backflush channel is connected to the pressure-inducing channel, wherein the backflush channel is used to pass backflush gas, and the flow direction of the backflush gas passed into the backflush channel is opposite to the flow direction of the pressure-inducing gas in the pressure-inducing channel.

6. A fluidized bed reactor level measuring device according to claim 5, characterized in that: The pressure-inducing pipe and the external pipe are connected via a three-way valve.

7. The fluidized bed reactor level measuring device according to claim 5, characterized in that: The backflush gas in the backflush channel on the external pipe operates in a continuous low-flow output or an intermittent high-flow output. A solenoid valve is provided on the external pipe to realize continuous output and intermittent output of the backflush gas and control the output flow rate of the backflush gas.

8. The fluidized bed reactor material level measuring device according to claim 6, characterized in that: A straight-through root valve is provided on the pressure-guiding pipe between the external pipe and the second end face of the connecting flange, and an air inlet end and an air outlet end are provided on the straight-through root valve, wherein both the air inlet end and the air outlet end are connected to the pressure-guiding pipe, or the air inlet end is connected to the pressure-guiding pipe, and the air outlet end is connected to the three-way valve.

9. The fluidized bed reactor material level measuring device according to claim 6, characterized in that: A straight-through root valve is arranged between the second port of the pressure-guiding pipe and the external pipe, and an air inlet end and an air outlet end are arranged on the straight-through root valve, wherein the air inlet end and the air outlet end are both connected to the pressure-guiding pipe, or the air inlet end is connected to the three-way valve, and the air outlet end is connected to the pressure-guiding pipe.

10. The fluidized bed reactor material level measuring device according to claim 4, characterized in that: The connecting flange is arranged in a stepped shape, and comprises a connecting portion and a positioning portion, wherein the first end surface is arranged on the connecting portion, and the second end surface is arranged on the positioning portion.

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