Phthalic anhydride preparation device with explosion venting unit

Abstract

The utility model provides a phthalic anhydride preparation device with an explosion venting unit, which comprises a phthalic anhydride oxidizer and a phthalic anhydride catcher, the phthalic anhydride oxidizer is also provided with the explosion venting unit, the phthalic anhydride oxidizer is connected with the phthalic anhydride catcher through a discharge pipe, the phthalic anhydride oxidizer is connected with the explosion venting unit through an explosion venting pipe, and the explosion venting unit is connected with the phthalic anhydride oxidizer through a discharge pipe. The explosion venting unit comprises a middle storage tank and a discharge pipe, the discharge pipe penetrates through an upper end cover of the middle storage tank, a pressure relief assembly is arranged at the joint of the interior of the middle storage tank and the discharge pipe, an elastic film is arranged in the pressure relief assembly, and when the pressure in the middle storage tank is larger than a preset value, the elastic film is opened for pressure relief.

Description

TECHNICAL FIELD

[0001] The utility model belongs to the field of phthalic anhydride preparation, especially, relate to a phthalic anhydride preparation device with explosion venting unit. BACKGROUND

[0002] Phthalic anhydride is phthalic anhydride, is an organic compound, chemical formula is C8H4O3, is the cyclic anhydride formed in phthalic acid molecule dehydration, is white crystalline powder, insoluble in cold water, slightly soluble in hot water, diethyl ether, soluble in ethanol, pyridine, benzene, carbon disulfide etc., is important organic chemical raw material, is the important intermediate for preparing phthalate plasticizer, paint, saccharin, dye and organic compound. At present, the preparation of phthalic anhydride is mainly through o-xylene air oxidation. Oxidation reaction is the intense heat reaction, phthalic anhydride oxidation adopts continuous reaction, has the risk of reaction out of control, therefore needs to be provided with explosion venting device on phthalic anhydride oxidation reactor, the existing explosion venting device is directly connected with the outside environment, so that even in the case of slight overpressure, a small amount of pressure relief will pollute the environment. SUMMARY

[0003] Based on the above problems existing in the prior art, the purpose of the utility model embodiment is to provide a phthalic anhydride preparation device with explosion venting unit to solve the process safety problem of phthalic anhydride oxidation exothermic existing in the prior art.

[0004] To achieve the above object, the technical scheme adopted by the utility model is: provide a phthalic anhydride preparation device with explosion venting unit, comprising: phthalic anhydride oxidizer and phthalic anhydride catcher, the phthalic anhydride oxidizer is also provided with explosion venting unit, the phthalic anhydride oxidizer and phthalic anhydride catcher are connected through the discharge pipe, the phthalic anhydride oxidizer and explosion venting unit are connected through the explosion venting pipe, the explosion venting unit includes intermediate storage tank and discharge pipe, the discharge pipe penetrates the upper end cover of the intermediate storage tank, the intermediate storage tank and the discharge pipe connection are provided with pressure relief assembly, the pressure relief assembly is provided with elastic diaphragm, when the pressure in the intermediate storage tank is greater than the preset value, the elastic diaphragm opens and releases pressure.

[0005] Preferably, the bottom of the phthalic anhydride oxidizer is provided with an air duct, and the inside of the phthalic anhydride oxidizer is provided with a first catalyst bed and a second catalyst bed.

[0006] Preferably, the sidewall of the phthalic anhydride oxidizer is provided with a first o-xylene duct and a second o-xylene duct, the first o-xylene duct is arranged between the first catalyst bed and the bottom of the phthalic anhydride oxidizer, and the second o-xylene duct is arranged between the first catalyst bed and the second catalyst bed.

[0007] Preferably, a safety valve is arranged between the phthalic anhydride oxidizer and the explosion venting pipe.

[0008] Preferably, a vacuum interface is arranged on the sidewall of the intermediate storage tank, and a valve is arranged on the vacuum interface, and the vacuum interface is connected with a vacuum unit pipeline.

[0009] Preferably, a pressure detection device is further arranged on the sidewall of the intermediate storage tank, and the pressure detection device is electrically connected with the valve.

[0010] Preferably, the pressure relief assembly comprises an outlet pipe and a valve body, and the outlet pipe is communicated with the discharge pipe.

[0011] Preferably, the valve body comprises a first sidewall and a second sidewall, a first opening is arranged on the first sidewall, a first pressing plate and a second pressing plate are arranged in the valve body, notches are arranged on the first pressing plate and the second pressing plate, and an elastic film is arranged on the notches.

[0012] Preferably, a steel needle is arranged on the second sidewall, and a sharp corner is arranged on the end of the steel needle away from the second sidewall.

[0013] Preferably, fixing members are arranged on the first pressing plate and the second pressing plate, and the elastic film can be fixed between the first pressing plate and the second pressing plate by locking the fixing members.

[0014] Compared with the prior art, the one or more technical schemes provided in the embodiment of the utility model have at least one of the following beneficial effects: the utility model provides a phthalic anhydride preparation device with a pressure relief unit, comprising: a phthalic anhydride oxidizer and a phthalic anhydride catcher, a pressure relief unit is further arranged on the phthalic anhydride oxidizer, the phthalic anhydride oxidizer and the phthalic anhydride catcher are connected through a discharge pipe, the phthalic anhydride oxidizer and the pressure relief unit are connected through a pressure relief pipe, the pressure relief unit comprises an intermediate storage tank and a discharge pipe, the discharge pipe penetrates the upper end cover of the intermediate storage tank, a pressure relief assembly is arranged at the connection between the intermediate storage tank and the discharge pipe, an elastic film is arranged in the pressure relief assembly, and when the pressure in the intermediate storage tank is greater than a preset value, the elastic film opens to release pressure. Through the pressure relief unit provided in the utility model, when the phthalic anhydride oxidizer is overpressure, the pressure and the material can be released into the intermediate storage tank, when the pressure in the intermediate storage tank is not higher than the preset pressure, the pressure relief assembly is closed, so that the overflow of the released organic matter into the environment can be avoided, when the pressure in the intermediate storage tank is higher than the preset pressure, the pressure relief assembly is opened, and the pressure release part in the phthalic anhydride oxidizer is smooth. BRIEF DESCRIPTION OF DRAWINGS

[0015] Figure 1 It is a structure schematic view of the phthalic anhydride preparation device with a pressure relief unit in the utility model;

[0016] Figure 2 It is Figure 1 It is a sectional view;

[0017] Figure 3 It is Figure 2Schematic view of the middle pressure relief assembly structure;

[0018] Figure 4 For Figure 3 Schematic view of the internal structure of the middle pressure relief assembly;

[0019] Figure 5 For Figure 3 The pressure relief assembly shown in the top view;

[0020] Figure 6 For Figure 5 The sectional view along the A-A direction.

[0021] Wherein, 100, phthalic anhydride preparation device with explosion venting unit; 1, phthalic anhydride oxidizer; 11, air pipeline; 12, first o-xylene pipeline; 13, second o-xylene pipeline; 14, discharge pipe; 15, explosion venting pipe; 151, safety valve; 16, first catalyst bed; 17, second catalyst bed; 2, explosion venting unit; 21, intermediate storage tank; 211, vacuum interface; 212, valve; 22, pressure detection device; 23, discharge pipe; 24, pressure relief assembly; 241, outlet pipe; 242, valve body; 2421, first side wall; 2422, first opening; 2423, first pressing plate frame; 2424, second pressing plate frame; 2425, elastic diaphragm; 2426, fixing piece; 2427, second opening; 2428, second side wall; 2429, steel needle; 3, phthalic anhydride trap.

[0022] In order to more clearly illustrate the technical scheme in the embodiments of the present application, the following will briefly introduce the drawings needed to be used in the embodiments or prior art description. Obviously, the drawings in the following description are only some embodiments of the present application, and for those skilled in the art, other drawings can also be obtained without creative labor. DETAILED DESCRIPTION

[0023] In order to make the technical problems, technical schemes and beneficial effects of the present application more clearly understood, the following will further describe the present application in combination with the drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application, and are not used to limit the present application.

[0024] It should be noted that when an element is referred to as being "connected to" or "disposed on" another element, it can be directly on the other element or indirectly on the other element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or indirectly connected to the other element.

[0025] In the description of the utility model, it is necessary to explain, unless another explicit provision and limitation, the term "installation", "link", "connection" should do the broad sense understanding, for example, can be fixed connection, also can be detachable connection, or integrally connected;Can be mechanical connection, also can be electrical connection;Can be directly connected, also can indirectly connect through the intermediate medium, can be two elements inside the communication or two element's mutual action relation. For ordinary skilled in the art, the above-mentioned term can be understood according to the specific meaning in the utility model.

[0026] Throughout the specification, reference to "one embodiment" or "an embodiment" means that a specific feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the application. The appearances of the phrase "in one embodiment" or "in embodiments" in various places in the specification are not necessarily all referring to the same embodiment. Furthermore, the term "comprising" is intended to mean that the embodiments include at least the recited feature, structure, or characteristic, but not excluding others. In addition, where necessary, the

[0027] Please see Figure 1 and Figure 2 , now the utility model embodiment provides the air adjusting structure is explained. Please further combine and see Figure 1The phthalic anhydride preparation device 100 with the explosion relief unit comprises a phthalic anhydride oxidizer 1 and a phthalic anhydride catcher 3, the phthalic anhydride oxidizer 1 and the phthalic anhydride catcher 3 are connected through a discharge pipe 14, and the phthalic anhydride oxidizer 1 is further provided with an explosion relief unit 2, the phthalic anhydride oxidizer 1 and the explosion relief unit 2 are connected through an explosion relief pipe 15, the phthalic anhydride oxidizer 1 has two reaction bed layers in the embodiment, which are a first catalyst bed layer 16 and a second catalyst bed layer 17, respectively, the bottom of the phthalic anhydride oxidizer 1 is provided with an air pipeline 11, compressed air can be introduced into the phthalic anhydride oxidizer 1 through the air pipeline 11 as an oxidizing gas, the side wall of the phthalic anhydride oxidizer 1 is further provided with a first o-xylene pipeline 12 and a second o-xylene pipeline 13, the first o-xylene pipeline 12 is located between the bottom of the phthalic anhydride oxidizer 1 and the first catalyst bed layer 16, the second o-xylene pipeline 13 is located between the first catalyst bed layer 16 and the second catalyst bed layer 17, o-xylene is supplied to the first catalyst bed layer 16 through the first o-xylene pipeline 12, and o-xylene is supplied to the second catalyst bed layer 17 through the second o-xylene pipeline 13. A safety valve 151 is arranged at the connection between the explosion relief pipe 15 and the phthalic anhydride oxidizer 1, and the safety valve 151 will open to release pressure when the pressure in the phthalic anhydride oxidizer 1 is too high. The explosion relief unit 2 comprises an intermediate storage tank 21 and a discharge pipe 23, the intermediate storage tank 21 has a cylindrical shape, the discharge pipe 23 is arranged on the upper end face of the intermediate storage tank 21, and the upper end face of the intermediate storage tank 21 is further connected with the explosion relief pipe 15. The intermediate storage tank 21 is further provided with a pressure relief assembly 24, the pressure relief assembly 24 has a cubic shape, and the pressure relief assembly 24 is in communication with the discharge pipe 23. When the pressure in the phthalic anhydride oxidizer 1 exceeds a preset threshold value, the safety valve 151 responds quickly and opens, and the pressure and materials in the phthalic anhydride oxidizer 1 are discharged into the intermediate storage tank 21 through the discharge pipe 14, and the pressure in the intermediate storage tank 21 can be discharged through the discharge pipe 23, so that the pressure in the phthalic anhydride oxidizer 1 is prevented from being too high to cause an explosion of the phthalic anhydride oxidizer 1.

[0028] Further, please refer to Figures 3-6 The pressure relief assembly 24 comprises an outlet pipe 241 and a valve body 242, the outlet pipe 241 penetrates through the upper end face of the valve body 242 and is in communication with the inside of the valve body 242, and the other end of the outlet pipe 241 can be connected with the discharge pipe 23; the first side wall 2421 of the valve body 242 is provided with a first opening 2422, and the shape of the first opening 2422 is not limited to the circular shape shown in the figure, and can also be a square shape or other shapes. Please refer to Figure 4As shown, the valve body 242 is provided with a second opening 2427 on the upper end surface through which the outlet pipe 241 penetrates, the second opening 2427 is matched with the shape of the outlet pipe 241, and the outlet pipe 241 can be fixed in the second opening 2427 by welding or other means. The first and second pressing plate frames 2423 and 2424 are arranged in the interior of the valve body 242, the first and second pressing plate frames 2423 and 2424 are provided with notches, and the elastic film 2425 is arranged on the notches. Specifically, the first and second pressing plate frames 2423 and 2424 are arranged in parallel, the first pressing plate frame 2423 and the elastic film 2425 are arranged on a section parallel to the first side wall 2421, the first and second pressing plate frames 2423 and 2424 are fixed on the inner side wall of the valve body 242 away from the second opening 2427 and close to one side of the first opening 2422, the first and second pressing plate frames 2423 and 2424 are provided with fixing members 2426, the elastic film 2425 can be pressed between the first and second pressing plate frames 2423 and 2424 by tightening the fixing members 2426, the elastic film 2425 is a film made of elastic material, the main materials include rubber, latex, aluminum film and plastic, and the material is similar to that of a balloon, which can withstand a pressure of 0.05-0.2 MPa, and will be burst when being pricked by a sharp object when the pressure is 0.05 MPa. The valve body 242 can be divided into two cavities of the explosion venting unit 2 by the elastic film 2425, the cavity close to the first opening 2422 is in communication with the interior of the intermediate storage tank 21, and the cavity close to the second opening 2427 is in communication with the discharge pipe 23. The steel needle 2429 is arranged on the second side wall 2428 opposite to the first side wall 2421 of the valve body 242, the end of the steel needle 2429 is processed into a sharp angle, the position of the steel needle 2429 on the second side wall 2428 corresponds to the geometric center of the elastic film 2425, and the length of the steel needle 2429 is the position of the geometric center of the elastic film 2425 when the elastic film 2425 is deformed to 0.05 MPa. That is, when the pressure in the intermediate storage tank 21 reaches 0.05 MPa, the elastic film 2425 will be deformed towards the steel needle 2429, and the elastic film 2425 will be burst when contacting the sharp end of the steel needle 2429, at this time, the discharge pipe 23 and the intermediate storage tank 21 are communicated, and the pressure in the intermediate storage tank 21 can be released to the outside.

[0029] In some embodiments, the intermediate storage tank 21 is a cylindrical barrel with a semicircular cover at the top end, the explosion venting pipe 15 is connected to the semicircular cover, and the discharge pipe 23 is also arranged on the semicircular cover. The vacuum interface 211 is arranged on the side wall of the barrel, the valve 212 is arranged on the vacuum interface 211, the other end of the vacuum interface 211 is connected to the pipeline of the vacuum unit, and the vacuum unit can provide negative pressure for the intermediate storage tank 21 by opening the valve 212.

[0030] In some embodiments, the valve 212 is an electromagnetic valve, and a pressure detection device 22 is further arranged on the side wall of the intermediate storage tank 21, the pressure detection device 22 can measure the pressure value in the intermediate storage tank 21, the valve 212 and the pressure detection device 22 are electrically connected, and the valve 212 and the vacuum unit are electrically connected, when the pressure on the pressure detection device 22 is higher than-0.08Mpa and lower than-0.02Mpa, the valve 212 is automatically controlled to be opened, the valve 212 is linked to control the vacuum unit to be started, and vacuum is supplemented in the intermediate storage tank 21, the condition that the condition is lower than-0.02Mpa is set in the condition, so that when an accident occurs, the intermediate storage tank 21 is filled with explosion relief gas and materials, and the vacuum is reduced to avoid the vacuum unit from being mistakenly started; when the pressure on the pressure detection device 22 is less than-0.095Mpa, the valve 212 is automatically controlled to be closed, and the vacuum unit is stopped.

[0031] The benzene anhydride preparation device 100 with the explosion relief unit 2 provided by the utility model provides-0.095~-0.08Mpa negative pressure through a vacuum unit, in normal operation, the safety valve 151 is closed, and the product prepared through the benzene anhydride oxidizer 1 enters the benzene anhydride catcher 3, when the benzene anhydride oxidizer 1 appears abnormal pressure higher than the preset value of the safety valve 151, the safety valve 151 is opened, and the air pressure and materials are discharged into the intermediate storage tank 21 through the explosion relief pipe 15, because the intermediate storage tank 21 is previously set to negative pressure, the pressure and materials in the benzene anhydride oxidizer 1 can be discharged faster, when the pressure in the intermediate storage tank 21 reaches 0.05Mpa, the elastic diaphragm 2425 is extruded to be deformed, and is punctured when contacting the steel needle 2429, so that the pressure in the intermediate storage tank 21 is prevented from being too high, and the air pressure and materials in the benzene anhydride oxidizer 1 are discharged, when the pressure in the intermediate storage tank 21 does not exceed 0.05Mpa, the elastic diaphragm 2425 is not punctured, and the high-temperature organic matter in the intermediate storage tank 21 can be prevented from being discharged to the outside.

[0032] The above merely describes the preferred embodiments of the utility model and is not used to limit the utility model, and any modification, equivalent replacement and improvement made within the spirit and principle of the utility model should be included in the protection scope of the utility model.

Claims

1. A phthalic anhydride production plant having a venting unit, characterized in that, include: The phthalic anhydride oxidizer (1) and the phthalic anhydride trap (3) are provided. The phthalic anhydride oxidizer (1) is also provided with a venting unit (2). The phthalic anhydride oxidizer (1) and the phthalic anhydride trap (3) are connected by a discharge pipe (14). The phthalic anhydride oxidizer (1) and the venting unit (2) are connected by a venting pipe (15). The venting unit (2) includes an intermediate storage tank (21) and a discharge pipe (23). The discharge pipe (23) passes through the upper end cover of the intermediate storage tank (21). A pressure relief component (24) is provided at the connection between the intermediate storage tank (21) and the discharge pipe (23). An elastic membrane (2425) is provided in the pressure relief component (24). When the pressure in the intermediate storage tank (21) is greater than a preset value, the elastic membrane (2425) opens to relieve pressure.

2. The phthalic anhydride production plant with a venting unit according to claim 1, characterized in that, The bottom of the phthalic anhydride oxidizer (1) is provided with an air duct (11), and the interior of the phthalic anhydride oxidizer (1) is provided with a first catalyst bed (16) and a second catalyst bed (17).

3. The phthalic anhydride production plant with a venting unit according to claim 2, characterized in that, The phthalic anhydride oxidizer (1) has a first o-xylene pipe (12) and a second o-xylene pipe (13) on its side wall. The first o-xylene pipe (12) is located between the first catalyst bed (16) and the bottom of the phthalic anhydride oxidizer (1), and the second o-xylene pipe (13) is located between the first catalyst bed (16) and the second catalyst bed (17).

4. The phthalic anhydride production apparatus having a venting unit according to claim 1, wherein A safety valve (151) is provided between the phthalic anhydride oxidizer (1) and the explosion relief pipe (15).

5. The phthalic anhydride production plant with a pressure relief unit according to claim 1, characterized in that, The intermediate storage tank (21) is provided with a vacuum interface (211) on its side wall. The vacuum interface (211) is provided with a valve (212). The vacuum interface (211) is connected to the vacuum unit pipeline.

6. The phthalic anhydride production plant with a venting unit according to claim 5, characterized in that, The intermediate storage tank (21) is also provided with a pressure detection device (22) on its side wall, and the pressure detection device (22) is electrically connected to the valve (212).

7. The phthalic anhydride production plant with a pressure relief unit according to claim 1, characterized in that, The pressure relief assembly (24) includes an outlet pipe (241) and a valve body (242), and the outlet pipe (241) and the discharge pipe (23) are connected.

8. The phthalic anhydride production plant with a pressure relief unit according to claim 7, characterized in that, The valve body (242) includes a first sidewall (2421) and a second sidewall (2428). The first sidewall (2421) has a first opening (2422). The valve body (242) has a first pressure plate (2423) and a second pressure plate (2424) inside. The first pressure plate (2423) and the second pressure plate (2424) have notches, and an elastic film (2425) is pressed onto the notches.

9. The phthalic anhydride production plant with a pressure relief unit according to claim 8, characterized in that, The second sidewall (2428) is provided with a steel needle (2429), and the end of the steel needle (2429) away from the second sidewall (2428) is processed into a sharp angle.

10. The phthalic anhydride production plant with a venting unit according to claim 9, characterized in that, The first pressure plate (2423) and the second pressure plate (2424) are provided with a fixing member (2426), and the elastic film (2425) can be fixed between the first pressure plate (2423) and the second pressure plate (2424) by locking the fixing member (2426).

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