CN211752116U

CN211752116U - Naphthalene method phthalic anhydride vaporizer safety fire extinguishing system

Info

Publication number: CN211752116U
Application number: CN201922448436.8U
Authority: CN
Inventors: 周保红; 赵耀; 景汝山; 董长胜
Original assignee: Shandong Hongxin Chemicals Co ltd
Current assignee: Shandong Hongxin Chemicals Co ltd
Priority date: 2019-12-28
Filing date: 2019-12-28
Publication date: 2020-10-27
Anticipated expiration: 2029-12-28

Abstract

The utility model belongs to the technical field of naphthalene process phthalic anhydride vaporizer, concretely relates to naphthalene process phthalic anhydride vaporizer safety fire extinguishing system, including naphthalene evaporator, air-blower, air heater and vaporizer, naphthalene evaporator is connected with the vaporizer through gas naphthalene trip valve, and the air-blower passes through air heater and vaporizer and is connected, is equipped with air blow-down valve between air-blower and air heater, is equipped with the temperature monitoring point at vaporizer lower part distribution awl, and lower part distribution awl is connected with the distribution station of filling nitrogen through filling nitrogen solenoid valve, and gas naphthalene trip valve, air-blower, air blow-down valve and the solenoid valve of filling nitrogen all are connected with the temperature monitoring point electricity. The utility model can monitor the temperature of the lower distribution cone of the vaporizer in real time, and replace manual operation with the quick reaction of the interlocking system, thereby reducing the probability of the occurrence of the combustion accident of the lower distribution cone of the vaporizer; meanwhile, once a combustion accident occurs, the system can reduce the consequence of the combustion accident and ensure the safety of the production of the naphthalene method phthalic anhydride.

Description

Naphthalene method phthalic anhydride vaporizer safety fire extinguishing system

Technical Field

The utility model belongs to the technical field of naphthalene method phthalic anhydride vaporizer, concretely relates to naphthalene method phthalic anhydride vaporizer safety fire extinguishing system.

Background

Phthalic anhydride is four major organic anhydrides with wide application range, and can be directly used for producing plasticizers, unsaturated polyester resins, alkyd resins and the like. In addition, phthalic anhydride is used in the industrial fields of inks, rubbers, paints, printing, etc., and is also used for producing pesticides, medicines, etc.

At present, the domestic phthalic anhydride production has an o-benzene route and an industrial naphthalene route. The technological process of the oxidation section of the industrial naphthalene route is that air is pressurized by a blower and preheated by an air heater and then is sent to a vaporizer; liquid naphthalene is pressurized by a pump, vaporized by a naphthalene evaporator and then sent to a vaporizer by a gas naphthalene pipeline; air and naphthalene are uniformly mixed in a vaporizer and then enter a fixed bed reactor filled with a catalyst to react to generate a target product, namely phthalic anhydride and a small part of byproducts. The reaction gas is pre-cooled by a gas cooler and then enters a hot melting box (usually four or five hot melting boxes are used in parallel); the phthalic anhydride is trapped and the waste gas is discharged when the hot melting box is condensed, and the phthalic anhydride is put into a crude phthalic anhydride tank when the hot melting box is hot-melted. The vaporizer is internally provided with two distribution cones, namely a lower distribution cone and an upper distribution cone, which are beneficial to the full mixing of the gas naphthalene and the air.

The purity of liquid naphthalene is only about 97%, and the impurities contained in the liquid naphthalene are discharged from a naphthalene evaporator, and a part of the impurities enter a subsequent system along with gaseous materials, so that the lower distribution cone of a vaporizer is easily blocked. The part of the blockage can generate a plurality of chemical reactions under the high-temperature oxygen-enriched condition to form an indefinite complex mixture such as carbon deposition, coking, colloid, asphaltene and the like, and the part of the mixture can be continuously combusted under unknown reasons, so that the oxidation reaction system can flash and explode, and the vaporizer can be burnt. The accidents of the fire and flash explosion of the vaporizer and the burnout of the vaporizer occur in various manufacturers in the phthalic anhydride industry. The problem of blockage of the distribution cone at the lower part of the vaporizer cannot be solved all the time due to the limitation of the purity of liquid naphthalene.

SUMMERY OF THE UTILITY MODEL

The to-be-solved technical problem of the utility model is: the shortcomings of the prior art are overcome, and the naphthalene method phthalic anhydride vaporizer safety fire extinguishing system is provided, manual operation is replaced by rapid reaction of an interlocking system, so that the probability of combustion accidents of a distribution cone at the lower part of the vaporizer is reduced; meanwhile, once a combustion accident occurs, the system can reduce the consequence of the combustion accident and ensure the safety of the production of the naphthalene method phthalic anhydride.

The utility model discloses an adopt following technical scheme to realize:

the safe fire extinguishing system of the naphthalene process phthalic anhydride vaporizer comprises a naphthalene evaporator, a blower, an air heater and a vaporizer, wherein the vaporizer comprises an upper distribution cone and a lower distribution cone, the upper distribution cone is sequentially connected with a reactor, a gas cooler and a hot melting box, and the hot melting box is connected with a crude phthalic anhydride tank. Naphthalene evaporator be connected with the vaporizer through gas naphthalene trip valve, the air-blower pass through air heater and vaporizer and be connected air-blower and air heater between be equipped with air atmospheric valve the lower part distributes and bores and is equipped with the temperature monitoring point, the lower part distributes and bores and is connected with the nitrogen distribution platform through filling nitrogen solenoid valve, gas naphthalene trip valve, air-blower, air atmospheric valve and fill nitrogen solenoid valve all be connected with the temperature monitoring point electricity.

And a one-way explosion-proof sheet is arranged in a pipeline between the lower distribution cone and the nitrogen charging electromagnetic valve. Under normal conditions, organic materials can be prevented from entering a nitrogen pipeline to be condensed to cause the blockage of the nitrogen pipeline; under the abnormal condition, the nitrogen-filled electromagnetic valve is opened, and the pressure of the nitrogen can lead the one-way explosion-proof sheet to be broken, thereby ensuring the continuous introduction of the nitrogen.

When the device is normally produced, the air naphthalene cut-off valve is in a normally open state, the air blower is in an operating state, the air emptying valve is in a normally closed state, and the nitrogen filling electromagnetic valve is in a normally closed state. When the actual temperature detected by the temperature detection point is greater than or equal to the set interlocking temperature value, the temperature monitoring point sends a signal to the control system, the control system outputs a signal to control the gas naphthalene cut-off valve to be closed, the air blower to be closed, the air emptying valve to be in an open state, the combustible and the combustion-supporting materials to be quickly cut off, the nitrogen-filled electromagnetic valve to be opened, nitrogen inert gas is filled to extinguish the fire, and the emergency interlocking stop of the system is realized.

Compared with the prior art, the beneficial effects of the utility model are as follows:

the utility model can monitor the temperature of the lower distribution cone of the vaporizer in real time, and replace manual operation with the quick reaction of the interlocking system, thereby reducing the probability of the occurrence of the combustion accident of the lower distribution cone of the vaporizer; meanwhile, once a combustion accident occurs, the system can reduce the consequence of the combustion accident and ensure the safety of the production of the naphthalene method phthalic anhydride.

Drawings

Fig. 1 is a schematic structural view of the present invention;

fig. 2 is a flow chart of an interlock logic in an embodiment of the present invention;

in the figure: 1. a naphthalene evaporator; 2. a gas naphthalene cut-off valve; 3. a temperature monitoring point; 4. a vaporizer; 4a, an upper distribution cone; 4b, a lower distribution cone; 5. a reactor; 6. a hot melting box; 7. a crude phthalic anhydride tank; 8. a gas cooler; 9. a nitrogen-filled distribution table; 10. a nitrogen charging electromagnetic valve; 11. a one-way explosion-proof sheet; 12. an air heater; 13. an air vent valve; 14. a blower.

Detailed Description

The present invention will be further described with reference to the accompanying drawings.

As shown in figure 1, naphthalene method phthalic anhydride vaporizer safety fire extinguishing system, including naphthalene evaporator 1, air-blower 14, air heater 12 and vaporizer 4, vaporizer 4 includes upper portion distribution awl 4a and lower part distribution awl 4b, naphthalene evaporator 1 be connected with vaporizer 4 through gas naphthalene trip valve 2, air-blower 14 be connected with vaporizer 4 through air heater 12 be equipped with air blow-down valve 13 between air-blower 14 and air heater 12, lower part distribution awl 4b is equipped with temperature monitoring point 3, lower part distribution awl 4b is connected with nitrogen charging distribution platform 9 through nitrogen charging solenoid valve 10, gas naphthalene trip valve 2, air-blower 14, air blow-down valve 13 and nitrogen charging solenoid valve 10 all be connected with temperature monitoring point 3 electricity.

And a one-way explosion-proof sheet 11 is arranged in a pipeline between the lower distribution cone 4b and the nitrogen charging electromagnetic valve 10.

The upper distribution cone 4a is sequentially connected with the reactor 5, the gas cooler 8 and the hot melting box 6, and the hot melting box 6 is connected with the crude phthalic anhydride tank 7.

When the device is normally produced, the air naphthalene cut-off valve 2 is in a normally open state, the air blower 14 is in a running state, the air emptying valve 13 is in a normally closed state, and the nitrogen filling electromagnetic valve 10 is in a normally closed state.

As shown in fig. 2, the interlock program includes a temperature monitoring point 3, DCS and its internal interlock program, a gas naphthalene cut-off valve 2, an air vent valve 13, a blower 14, and a nitrogen charging solenoid valve 10. Wherein, the temperature monitoring point 3 completes the temperature detection and inputs signals to the DCS; the DCS receives signals input by the temperature monitoring points, compares the signals with an interlocking value preset in the DCS, and judges whether interlocking action signals need to be output to the air naphthalene cut-off valve 2, the air vent valve 13, the blower 14 and the nitrogen charging electromagnetic valve 10; and the air naphthalene cut-off valve 2, the air blow-off valve 13, the blower 14 and the nitrogen charging electromagnetic valve 10 perform corresponding interlocking actions according to the interlocking program output of the DCS.

The actual measured value T2 of the temperature monitoring point 3 is input into the DCS and an internal interlocking program thereof, and is compared with an interlocking value T1 preset in the DCS, if the condition T2 is not less than T1, the DCS sends out an interlocking action, the interlocking gas naphthalene cut-off valve 1 is closed, the air blow-off valve 13 is opened, the blower 14 is stopped, the nitrogen-filled electromagnetic valve 10 is opened, and the emergency interlocking stop of the system is realized.

The DCS interlocking program has quick response, and the combustible substances (the gas naphthalene cut-off valve 1 is closed), the combustion-supporting substances (the blower 14 is stopped, the air emptying valve 13 is opened) and the inert gas is flushed for fire extinguishing (the nitrogen filling electromagnetic valve 10 is opened) can be quickly cut off as long as T2 is more than or equal to T1.

Of course, the above description is only a preferred embodiment of the present invention, and should not be taken as limiting the scope of the embodiments of the present invention. The present invention is not limited to the above examples, and the technical field of the present invention is equivalent to the changes and improvements made in the actual range of the present invention, which should be attributed to the patent coverage of the present invention.

Claims

1. A naphthalene method phthalic anhydride vaporizer safety fire extinguishing system, includes naphthalene evaporator (1), air-blower (14), air heater (12) and vaporizer (4), vaporizer (4) are including upper portion distribution awl (4a) and lower part distribution awl (4b), its characterized in that: naphthalene evaporator (1) be connected with vaporizer (4) through gas naphthalene trip valve (2), air-blower (14) pass through air heater (12) and vaporizer (4) and be connected air-blower (14) and air heater (12) between be equipped with air atmospheric valve (13) lower part distribution awl (4b) are equipped with temperature monitoring point (3), lower part distribution awl (4b) are connected with nitrogen charging distribution platform (9) through nitrogen charging solenoid valve (10), gas naphthalene trip valve (2), air-blower (14), air atmospheric valve (13) and nitrogen charging solenoid valve (10) all be connected with temperature monitoring point (3) electricity.

2. The naphthalene phthalic anhydride vaporizer safety fire extinguishing system according to claim 1, wherein: and a one-way explosion-proof sheet (11) is arranged in a pipeline between the lower distribution cone (4b) and the nitrogen charging electromagnetic valve (10).

3. The naphthalene phthalic anhydride vaporizer safety fire extinguishing system according to claim 1, wherein: the upper distribution cone (4a) is sequentially connected with the reactor (5), the gas cooler (8) and the hot melting box (6), and the hot melting box (6) is connected with a crude phthalic anhydride tank (7).