Pressure relief device of esterification reaction kettle

Abstract

The utility model discloses a pressure relief device of an esterification reaction kettle, which comprises a reaction kettle body, a gas phase pipeline body arranged at the top of the reaction kettle body, a nitrogen input pipe obliquely arranged on the gas phase pipeline body, a first control valve arranged at the outer end of the nitrogen input pipe, and a nitrogen pipe connected with the first control valve, the device is characterized in that a pressure relief mechanism is arranged on the nitrogen pipe and comprises a second control valve arranged at the outer end of the nitrogen pipe, a pressure relief pipeline arranged at the outer end of the second control valve, an EG process tower arranged at the other end of the pressure relief pipeline and a third control valve arranged on the EG process tower; and after the first control valve, the second control valve and the third control valve are opened, redundant gas-phase substances in the reaction kettle body are discharged into the EG process tower and are subjected to three-phase separation. The esterification reaction kettle can solve the problem of unsmooth material passing caused by unsmooth vapor phase pipeline, ensures the productivity and quality of products, and is simple in structure, low in improvement cost and convenient to maintain and operate.

Description

TECHNICAL FIELD

[0001] The utility model relates to the technical field of esterification reaction kettle, specifically relates to an esterification reaction kettle pressure relief device. BACKGROUND

[0002] At present, in the polyester production device in our country, the flow of non-sticky material mainly relies on the pressure difference between the front and rear adjacent reaction kettles, thereby realizing self-flow. The vapor phase pipeline of the esterification reaction kettle is the channel for the esterification reaction product water vapor and a small amount of ethylene glycol vapor to separate from the reaction kettle, and the unobstructed vapor phase pipeline of the esterification kettle is the prerequisite for the reaction kettle not to be pressure-stopped and the esterification material to flow smoothly, and is also the necessary condition for the efficient and stable operation of the polyester device. However, it has been in a high-load operation state for many years. Since the second half of 2021, 12R01 to 13R01 has been difficult to flow and has been increasing, the workshop has been forced to maintain by increasing the pressure of 12R01 reaction kettle and regularly dredging from the pressure pipe and nitrogen port of 13R01 gas phase pipeline. The device capacity has not been maximized. In July this year, the situation suddenly deteriorated, and the above methods cannot achieve the effect of stable reaction kettle pressure and liquid level, making the yield improvement and product index stability become particularly passive, and bringing serious hidden dangers to production. SUMMARY

[0003] In order to solve the technical problems existing in the prior art, the purpose of the present application is to provide an esterification reaction kettle pressure relief device, which can solve the problem of material flow difficulty caused by the unsmooth vapor phase pipeline of the esterification reaction kettle, ensure the production capacity and quality of the product, and has the advantages of simple structure, low modification cost, and convenient maintenance and operation.

[0004] To solve the above technical problems, the present application adopts the following technical scheme:

[0005] An esterification reaction kettle pressure relief device, comprising a reaction kettle body, a gas phase pipeline body arranged at the top of the reaction kettle body, a nitrogen gas input pipe arranged obliquely on the gas phase pipeline body, a first control valve arranged at the outer end of the nitrogen gas input pipe, a nitrogen gas pipe connected with the first control valve, an EG process tower for supplying ethanol to the reaction kettle body, and a delivery pump, wherein a pressure relief mechanism is arranged on the nitrogen gas pipe, the pressure relief mechanism comprises a second control valve arranged at the outer end of the nitrogen gas pipe, a pressure relief pipeline arranged at the outer end of the second control valve, and a third control valve arranged at the other end of the pressure relief pipeline, the third control valve is arranged on the EG process tower, and the excess gas phase material in the reaction kettle body is discharged into the EG process tower and subjected to three-phase separation after the first control valve, the second control valve and the third control valve are opened.

[0006] Preferably, a pressure gauge is arranged on the nitrogen gas pipe.

[0007] Preferably, the outer end of the nitrogen pipe is provided with a Y-shaped three-way pipe, the EG process tower is provided with a T-shaped three-way pipe at the swing head, two said pressure relief pipes are connected between the Y-shaped three-way pipe and the T-shaped three-way pipe, and the two ends of the two said pressure relief pipes are respectively provided with the second control valve and the third control valve.

[0008] Preferably, a dredging mechanism is further arranged between the EG process tower and the two said pressure relief pipes, and the blocked pressure relief pipe is flushed and dredged through the dredging mechanism.

[0009] Preferably, the dredging mechanism comprises two high-temperature EG flushing pipelines in communication with the output pipeline of the delivery pump and a switch valve arranged on the high-temperature EG flushing pipeline.

[0010] Preferably, the second control valve and the third control valve are both DN25 ball valves.

[0011] Compared with the prior art, the esterification reactor of the utility model has the beneficial effects that:

[0012] The esterification reactor can solve the problem of unsmooth material flow caused by unsmooth vapor phase pipeline, can timely dredge the excess pressure in the reactor body to the outside through the pressure relief device, can stabilize the internal pressure and liquid level, can ensure the yield and product index, can ensure the full-load operation of the device, can maximize the production capacity, can improve the production stability and product index controllability, can ensure the production capacity and quality of the product, has simple structure, low modification cost, and convenient maintenance and operation. BRIEF DESCRIPTION OF DRAWINGS

[0013] Figure 1 The drawings show the structure of the utility model;

[0014] In the drawings: 1, reactor body; 2, vapor phase pipeline body; 3, nitrogen input pipe; 4, first control valve; 5, pressure gauge; 6, Y-shaped three-way pipe; 7, second control valve; 8, EG flushing pipeline; 9, switch valve; 10, dredging mechanism; 11, pressure relief pipe; 12, third control valve; 13, T-shaped three-way pipe; 14, EG process tower; 15, delivery pump; 16, pressure relief mechanism; 17, nitrogen pipe. DETAILED DESCRIPTION

[0015] In the following, the application will be further described in combination with the drawings and specific embodiments, and it should be noted that the embodiments described below or the technical features thereof can be combined in any manner to form new embodiments without conflict.

[0016] In the description of this application, it should be understood that the terms "upper", "lower", "left", "right", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.

[0017] The terms "first," "second," etc., used in this application are used to distinguish similar objects and not to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that embodiments of this application can be implemented in orders other than those illustrated or described herein, and the objects distinguished by "first," "second," etc., are generally of the same class, without limiting the number of objects; for example, a first object can be one or more. Furthermore, in the specification and claims, "and / or" indicates at least one of the connected objects, and the character " / " generally indicates that the preceding and following objects are in an "or" relationship.

[0018] like Figure 1 As shown, an esterification reactor pressure relief device includes a reactor body 1, a gas phase pipeline body 2 located at the top of the reactor body 1, a nitrogen input pipe 3 inclinedly located on the gas phase pipeline body 2, a first control valve 4 located at the outer end of the nitrogen input pipe 3, and a nitrogen pipe 17 connected to the first control valve 4. The nitrogen pipe 17 is provided with a pressure relief mechanism 16, which includes a second control valve 7 located at the outer end of the nitrogen pipe 17, a pressure relief pipe 11 located at the outer end of the second control valve 7, an EG process tower 14 located at the other end of the pressure relief pipe 11, and a third control valve 12 located on the EG process tower 14. Excess gaseous substances in the reactor body 1 are discharged into the EG process tower 14 and subjected to three-phase separation after opening the first control valve 4, the second control valve 7, and the third control valve 12.

[0019] In actual production and modification process, the EG process column 14 supplies ethanol to the reaction kettle body 1 through the delivery pump 15, and in the closed state of the first control valve 4, the outer end of the original nitrogen pipe 17 is connected with the EG process column 14 through the pressure relief pipeline 11, and the two ends of the pressure relief pipeline 11 are connected through the second control valve 7 and the third control valve 12 respectively. When the pressure gauge 5 on the reaction kettle body 1 shows that the internal pressure is too large, the first control valve 4, the second control valve 7 and the third control valve 12 are opened, so that the reaction kettle body 1 is communicated with the EG process column 14 through the pressure relief pipeline 11, so that the excess gas phase material in the reaction kettle body 1 is discharged into the EG process column 14 through the pressure relief pipeline 11 and is subjected to three-phase separation, thereby solving the problem of excessive internal pressure of the reaction kettle body 1, solving the problem of material flow caused by the unsmooth vapor phase pipeline of the esterification reactor, and making the excess pressure in the reaction kettle body 1 be discharged to the outside in time through the pressure relief device, so that the internal pressure and liquid level are stable, the yield is improved, the product index is stable, the device yield is full load operation, the production capacity is maximized, the production stability and product index controllability are improved, the product yield and quality are guaranteed, the structure is simple, the modification cost is low, and the maintenance and operation are convenient.

[0020] Further improvement is that the nitrogen pipe 17 is provided with a pressure gauge 5.

[0021] Since the pressure gauge 5 of the reaction kettle body 1 monitors the pressure in the reaction kettle body 1, the monitoring area is far away from the vapor phase pipeline body 2, so when the pressure of the vapor phase pipeline body 2 is too large, the pressure gauge 5 itself may still be within the normal range, thereby causing data deviation and affecting process production. Therefore, in order to ensure the accuracy of the internal pressure of the vapor phase pipeline body 2, a pressure gauge 5 is installed on the nitrogen pipe 17, and the first control valve 4 is in the open state under normal circumstances, so that the pressure in the vapor phase pipeline body 2 can be monitored in real time through the pressure gauge 5 on the nitrogen pipe 17, and the reaction kettle pressure change can be accurately tracked. The valve in the pipeline is adjusted to keep the pressure in the reaction kettle stable, and the esterification material flow is smooth.

[0022] Further improvement is that the outer end of the nitrogen pipe 17 is provided with a Y-shaped three-way pipeline 6, the tail of the EG process column 14 is provided with a T-shaped three-way pipeline 13, and two pressure relief pipelines 11 are connected between the Y-shaped three-way pipeline 6 and the T-shaped three-way pipeline 13. The two ends of the two pressure relief pipelines 11 are respectively provided with the second control valve 7 and the third control valve 12.

[0023] Since the pressure relief pipeline 11 is easy to scale after running for a period of time due to the accumulation of esterification entrainment, affecting the use effect, and the disassembly of the pressure relief pipeline 11 is relatively troublesome, therefore, in order to ensure that the problem of not being able to timely relieve pressure when one of the pressure relief pipelines 11 is blocked, two pressure relief pipelines 11 are installed between the reaction kettle body 1 and the EG process tower 14, when one of them is blocked, it can be switched to the standby pipeline, thereby ensuring the internal smoothness during pressure relief, since the pressure inside the reaction kettle body 1 is high during pressure relief, the gas impact force is large, therefore, the conventional tee pipeline is easy to be blocked due to the corner during pressure relief, for this reason, the tee pipeline at the outer end of the nitrogen pipe 17 is customized to be a Y-shaped tee pipeline 6 structure, thereby making the internal substances more smooth when being impacted outward under high pressure, and when entering the EG process tower 14, it enters through the swing head, at this time, the tee can use a conventional T-shaped tee 13, which is more convenient to purchase.

[0024] Further improvement is that the EG process tower 14 and the two pressure relief pipelines 11 are further provided with a dredging mechanism 10, and the blocked pressure relief pipeline 11 is flushed and dredged through the dredging mechanism 10; the dredging mechanism 10 includes two high-temperature EG flushing pipelines 8 in communication with the output pipeline of the delivery pump 15, and a switch valve 9 provided on the high-temperature EG flushing pipeline 8.

[0025] When the pressure relief pipeline 11 is blocked, the cleaning workload is too large and the disassembly is difficult, therefore, a dredging mechanism 10 is installed between the EG process tower 14 and the two pressure relief pipelines 11, when the blocked pressure relief pipeline 11 needs to be cleaned and dredged, it can be flushed and dredged through the dredging mechanism 10. The dredging mechanism 10 is composed of two high-temperature EG flushing pipelines 8 with a switch valve 9, since the delivery pipe of the delivery pump 15 of the EG process tower 14 is located near the nitrogen input pipe 3, the high-temperature EG flushing pipeline 8 can be directly connected from the EG delivery pipe connected with the delivery pump 15, when cleaning and dredging, after opening the switch valve 9, the high-temperature EG in the EG process tower 14 can be effectively used for flushing and cleaning, and finally it is used as a standby state, realizing online switching and long-term guarantee of the stability of the reaction kettle pressure and liquid level. After implementing this scheme, the liquid level control is more stable than before, and the product quality is effectively stabilized.

[0026] Further improvement is that the second control valve 7 and the third control valve 12 are both DN25 ball valves, which are simple in structure, low in modification cost, and convenient to maintain and operate; online smooth running and switching are realized, the whole operation has no external esterification gas body, all returns to the EG process tower 14, and is recycled again, realizing zero emission to the atmosphere.

[0027] The above embodiments are only the preferred embodiments of the present application, and cannot be used to limit the scope of protection of the present application, and any non-essential changes and replacements made by those skilled in the art on the basis of the present application shall fall within the scope of protection of the present application.

Claims

1. An esterification reactor pressure relief device, comprising a reactor body (1), a gas phase line body (2) provided at the top of the reactor body (1), a nitrogen input pipe (3) provided obliquely on the gas phase line body (2), a first control valve (4) provided at the outer end of the nitrogen input pipe (3), a nitrogen pipe (17) connected with the first control valve (4), an EG process column (14) and a delivery pump (15) for supplying ethanol to the reactor body (1), characterized in that: The nitrogen pipe (17) is provided with a pressure relief mechanism (16), the pressure relief mechanism (16) includes a second control valve (7) arranged at the outer end of the nitrogen pipe (17), a pressure relief pipeline (11) arranged at the outer end of the second control valve (7), and a third control valve (12) arranged at the other end of the pressure relief pipeline (11), the third control valve (12) is arranged on the EG process tower (14), and the excess gas phase material in the reaction kettle body (1) is discharged into the EG process tower (14) and subjected to three-phase separation by opening the first control valve (4), the second control valve (7) and the third control valve (12).

2. The pressure relief device of claim 1, wherein: The nitrogen pipe (17) is provided with a pressure gauge (5).

3. The pressure relief device of an esterification reactor according to claim 1 or 2, characterized in that: The outer end of the nitrogen pipe (17) is provided with a Y-shaped tee pipe (6), the EG process tower (14) is provided with a T-shaped tee pipe (13), and two pressure relief pipelines (11) are connected between the Y-shaped tee pipe (6) and the T-shaped tee pipe (13), and the two ends of the two pressure relief pipelines (11) are respectively provided with the second control valve (7) and the third control valve (12).

4. The pressure relief device of claim 3, wherein: The EG process tower (14) and the two pressure relief pipelines (11) are further provided with a dredging mechanism (10), and the blocked pressure relief pipeline (11) is flushed and dredged by the dredging mechanism (10).

5. The pressure relief device of claim 4, wherein: The dredging mechanism (10) includes two high-temperature EG flushing pipelines (8) in communication with the output pipeline of the delivery pump (15) and a switch valve (9) arranged on the high-temperature EG flushing pipeline (8).

6. The pressure relief device of claim 3, wherein: The second control valve (7) and the third control valve (12) are both DN25 ball valves.

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