Methanol VOCs gas treatment device

Abstract

The utility model provides a methanol VOCs gas treatment device which comprises an absorption tower, one side of the absorption tower is connected with a desalted water pipeline and a liquid seal device, the bottom of the absorption tower is connected with the input end of a cooler, the output end of the cooler is connected with an extraction pipeline, the extraction pipeline is connected with a circulation pipeline, the circulation pipeline is connected with the absorption tower, and the liquid seal device is connected with the liquid seal device. The top of the absorption tower is connected with an exhaust pipeline; the tail gas passes through the liquid seal tank before entering the absorption tower, so that the connection with a front-end device is blocked, the front-end working condition is not influenced, and the safe operation of the device is further ensured; the problem of safety relevance between the device and a front section is greatly reduced, meanwhile, the device can be suitable for various working conditions, and the safety problem is solved when the device is used for treating various working conditions such as low concentration and high concentration of methanol VOCs; in addition, through the arrangement of a flame arrester and an anti-explosion fan, connection with a rear-end device can be blocked, the effect of not influencing the rear-section working condition is achieved, and safe operation of the device is further ensured.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of methanol VOCs gas purification treatment, in particular to a methanol VOCs gas treatment device. BACKGROUND

[0002] At the current stage, the fine particulate matter (PM2.5) pollution situation in China is still severe, and ozone (O3) pollution is increasingly prominent. In summer, O3 has become the primary factor leading to air quality exceeding standards in some cities. Sulfur dioxide (SO2), nitrogen oxides (NO x ), smoke dust, and volatile organic compounds (VOCs) are all important precursors of PM2.5 and O3. In recent years, the management and control of the first three (sulfur dioxide (SO2), nitrogen oxides (NO x ), and smoke dust) have made significant progress. In comparison, the management and control of VOCs are relatively weak, which has become a shortcoming in China's atmospheric environmental governance. The petrochemical, chemical, industrial coating, packaging printing, and oil storage and transportation industries are key sources of VOCs emissions in China. In order to win the battle for a blue sky and further improve environmental air quality, it is urgent to comprehensively strengthen the comprehensive management of VOCs in key industries.

[0003] In order to solve the above technical problems, the application number 202211035131.4 methanol storage area, methanol loading VOCs gas treatment system discloses a technical solution, which includes: a storage tank is provided in the methanol storage area, a nitrogen sealing facility, an exhaust gas collection pipeline, a single call valve, and a flame arrester are sequentially provided on the top of the storage tank, and manual valves are provided before and after the flame arrester; a nitrogen sealing valve group and a safety valve are provided on the upper part of the inlet of the crude alcohol underground tank, a check valve and a flame arrester are provided on the outlet of the crude alcohol underground tank, and manual valves are provided before and after the flame arrester; a fan, a flame arrester, and a manual valve are provided before the exhaust gas treatment facility, and an online alcohol content analyzer, a shut-off valve, and a vent valve are provided after the exhaust gas treatment facility; the loading facility of the methanol loading includes an upper loading facility and a liquid loading facility added on the rear side of the upper loading facility, and the (liquid phase + gas phase) loading crane pipe adopts a complete universal joint filling; in the invention, the exhaust gas collected and purified is sent to a comprehensive heating furnace and a coke oven gas heating furnace for air distribution, and the exhaust gas is cracked under high temperature conditions to achieve VOCs emission standard discharge; the application can achieve VOCs emission standard discharge, but the application focuses more on the connection and interlocking with the front and rear equipment, and the safety factor is relatively low. The present application aims to improve the washing process of the washing tower to ensure VOCs emission standard discharge while improving the safety factor.

[0004] Through detailed retrieval of the prior art, no application related to the idea of the present application has been found. Therefore, a new scheme is needed to solve the above technical problems. CONTENT OF THE UTILITY MODEL

[0005] The application provides a methanol VOCs gas treatment device, which comprises an absorption tower, a desalted water pipeline and a liquid seal device are connected to one side of the absorption tower, the bottom of the absorption tower is connected with the input end of a cooler, the output end of the cooler is connected with a production pipeline, a circulating pipeline is connected to the production pipeline, the circulating pipeline is connected with the absorption tower, and an exhaust pipeline is connected to the top of the absorption tower.

[0006] As a preferred solution, the exhaust pipeline is provided with a flame arrester, and the rear part of the flame arrester is provided with an explosion-proof fan.

[0007] As a preferred solution, the explosion-proof fan comprises an explosion-proof fan one and an explosion-proof fan two which are connected in parallel.

[0008] As a preferred solution, the desalted water pipeline is connected with one end of a desalted pipeline one, and the other end of the desalted pipeline one is connected with the absorption tower.

[0009] As a preferred solution, the liquid seal device comprises a liquid seal tank one and a liquid seal tank two, one side of the liquid seal tank one is connected with an air inlet pipeline one, the air inlet pipeline one is connected with a cooler one, the top of the liquid seal tank one is connected with the absorption tower through a top pipeline one, and the bottom of the liquid seal tank one is connected with the absorption tower through a liquid seal tank one tower kettle pipeline; one side of the liquid seal tank two is connected with an air inlet pipeline two, the air inlet pipeline two is connected with a cooler two, the top of the liquid seal tank two is connected with the absorption tower through a top pipeline two, and the bottom of the liquid seal tank two is connected with the absorption tower through a liquid seal tank two tower kettle pipeline.

[0010] As a preferred solution, the top pipeline two is communicated with the top pipeline one.

[0011] As a preferred solution, the liquid seal tank two tower kettle pipeline is communicated with the liquid seal tank one tower kettle pipeline.

[0012] As a preferred solution, the bottom of the absorption tower is connected with the input end of the cooler through a production pipeline one, the production pipeline one is provided with a rich liquid production pump one, the production pipeline one is provided with a production pipeline two in parallel, and the production pipeline two is provided with a rich liquid production pump two.

[0013] As a preferred solution, a tower middle cooler is arranged in the middle of the absorption tower, and the tower middle cooler is connected with a cooling water inlet pipeline and a cooling water return pipeline.

[0014] The application is that the tail gas enters the liquid seal tank first before entering the absorption tower, the purpose is to block the connection with the front-end device, play the role of not affecting the working condition of the front section, further ensure the safe operation of the device, greatly reduce the safety correlation problem of the device and the front section, and can be suitable for various working conditions, treat various working conditions of low and high concentration of methanol VOCs, and the safety problem, and the application can block the connection with the rear-end device by the setting of the flame arrester and the explosion-proof fan, play the role of not affecting the working condition of the rear section, further ensure the safe operation of the device. BRIEF DESCRIPTION OF DRAWINGS

[0015] Figure 1 It is a structural schematic diagram of the application.

[0016] 1, absorption tower; 2, cooler in the tower; 3, cooling water inlet pipeline; 4, cooling water return pipeline; 5, desalted water pipeline; 6, desalted pipeline; 7, cooler; 8, circulating water inlet pipeline; 9, circulating water outlet pipeline; 10, production pipeline; 11, circulating pipeline; 12, production pipeline; 13, rich liquid production pump; 14, production pipeline; 15, rich liquid production pump; 16, exhaust pipeline; 17, flame arrester; 18, explosion-proof fan; 19, explosion-proof fan; 20, liquid seal tank; 21, liquid seal tank; 22, gas inlet pipeline; 23, cooler; 24, top pipeline; 25, liquid seal tank tower kettle pipeline; 26, gas inlet pipeline; 27, cooler; 28, top pipeline; 29, liquid seal tank tower kettle pipeline. DETAILED DESCRIPTION

[0017] The specific embodiments of the application will be described in detail below. Figure 1 It should be noted that the specific embodiments described herein are only used to illustrate and explain the application, and are not used to limit the application.

[0018] Example one:

[0019] As Figure 1As shown, the present application provides a methanol VOCs gas treatment device, which comprises an absorption tower 1, the absorption tower 1 adopts the absorption tower in the prior art, and four layers of large operation elastic trays and two layers of fillers are arranged in the absorption tower 1. The elastic tray is preferably an AZHF bent pipe tray of the company's patent tray, and the operation elastic range is 0%-130%; other trays in the prior art can also be used, and the specific tray is not limited; a tower middle cooler 2 is arranged in the middle of the absorption tower 1, the tower middle cooler 2 is connected with a cooling water inlet pipeline 3 and a cooling water return pipeline 4, and cooling is carried out through a cooling medium such as cooling water. The purpose of arranging the tower middle cooler 2 is to be more conducive to absorption at low temperature; one side of the absorption tower 1 is connected with a desalted water pipeline 5 and a liquid seal device, more specifically, the desalted water pipeline 5 is connected with one end of a desalted water pipeline I 6, the other end of the desalted water pipeline I 6 is connected with the absorption tower 1, and VOCs is washed with desalted water, the desalted water comes from the outside world and is divided into two streams, one stream enters from above the first tray of the absorption tower 1 through the desalted water pipeline 5, and the amount is very small, and the second stream enters from above the tower middle cooler 2 of the absorption tower 1 through the desalted water pipeline I 6; the bottom of the absorption tower 1 is connected with the input end of a cooler 7, the cooler 7 is connected with a circulating water inlet pipeline 8 and a circulating water outlet pipeline 9, and cooling is carried out through a cooling medium such as circulating water; the output end of the cooler 7 is connected with a production pipeline 10, the production pipeline 10 is connected with a circulating pipeline 11, and the circulating pipeline 11 is connected with the absorption tower 1; more specifically: the bottom of the absorption tower 1 is connected with the input end of the cooler 7 through a production pipeline I 2, a rich liquid production pump I 3 is arranged on the production pipeline I 2, a production pipeline II 4 is arranged in parallel on the production pipeline I 2, a rich liquid production pump II 5 is arranged on the production pipeline II 4, and the top of the absorption tower 1 is connected with an exhaust pipeline 16; the rich liquid desalted water of the tower kettle of the absorption tower 1 is cooled after being punched into the cooler 7, and then is punched into the upper part of the lowermost filler of the absorption tower 1 for secondary spray absorption, the purpose of the cooler 7 is to better absorb, this section is a key part of treating high VOCs content gas, which not only reduces the amount of desalted water, but also can absorb more VOCs, the middle filler of the absorption tower 1 plays a role in secondary absorption, the absorption tower 1 realizes multi-stage absorption, and can be suitable for various working conditions, the desalted water of the tower kettle is sent to a methanol rectification device as extraction water, the recovery rate of methanol is improved, and no waste liquid is generated.

[0020] Preferably, a flame arrester 17 is arranged on the exhaust pipeline 16, an explosion-proof fan is arranged at the rear of the flame arrester 17, the explosion-proof fan adopts a Roots blower, more preferably, the explosion-proof fan comprises explosion-proof fan I 18 and explosion-proof fan II 19 arranged in parallel; in the present application, the explosion-proof fan is arranged behind the flame arrester 17 of the exhaust pipeline 16 at the top of the absorption tower 1, so that the absorption tower 1 is in a state of micro-negative pressure, the risk of safe ignition is reduced, the connection with the rear equipment is blocked, and the effect of not affecting the subsequent section is achieved.

[0021] Example 2:

[0022] This embodiment provides a detailed description of the liquid seal device. The liquid seal device can block the connection with the front-end device, thus ensuring that the operation of the front-end is not affected. Specifically:

[0023] The liquid sealing device includes a liquid sealing tank 20 and a liquid sealing tank 21. The liquid in both liquid sealing tanks 20 and 21 is demineralized water. One side of liquid sealing tank 20 is connected to an inlet pipeline 22, which leads to the volatile gas in the loading area. A cooler 23 is connected to the inlet pipeline 22. The structure of cooler 23 is the same as that of cooler 7 described above; the different descriptions are to distinguish different installation positions. The top of liquid sealing tank 20 is connected to absorption tower 1 via a top pipeline 24, and the bottom of liquid sealing tank 20 is connected to absorption tower 1 via a bottom pipeline 25. One side of liquid sealing tank 21 is connected to an inlet pipeline 26, which leads to the breathing gas in the storage tank area. The breathing gas in the storage tank area includes, but is not limited to, the breathing gas from refined methanol storage tanks, crude methanol storage tanks, and fusel oil storage tanks. A cooler 27 is connected to the inlet pipeline 26. The structure of 27 is the same as that of the cooler 7 described above. The different descriptions are to distinguish the different installation positions. The top of the liquid seal tank 21 is connected to the absorption tower 1 through the top pipeline 28. Preferably, the top pipeline 28 is connected to the top pipeline 24. The gas phases extracted from the liquid seal tank 21 and the liquid seal tank 1 are mixed and then enter the absorption tower 1. The bottom of the liquid seal tank 21 is connected to the absorption tower 1 through the liquid seal tank 2 tower bottom pipeline 29. Preferably, the liquid seal tank 2 tower bottom pipeline 29 is connected to the liquid seal tank 1 tower bottom pipeline 25. In this embodiment, the volatile gas in the loading area and the breathing gas in the storage tank area are cooled by the cooler 23 and the cooler 27 before entering the absorption tower 1, and then pass through the liquid seal tank 1 20 and the liquid seal tank 21 respectively. The purpose is to cool and absorb better, and at the same time to block the connection with the front-end device, so as not to affect the front-end working conditions, and further ensure the safe operation of this device.

[0024] Preferably, VOC value-measuring devices are installed on the liquid seal tank 20 and the liquid seal tank 21. The VOC value-measuring devices adopt existing VOC gas detectors, which can monitor the VOC values ​​in the liquid seal tank 20 and the liquid seal tank 21 in real time. The replacement cycle of the demineralized water in the liquid seal tank 20 is adjusted by detecting the VOC value in the liquid seal tank 20, and the replacement cycle of the demineralized water in the liquid seal tank 21 is adjusted by detecting the VOC value in the liquid seal tank 21. When the demineralized water in the liquid seal tank 20 and the liquid seal tank 21 is replaced, it can be automatically discharged into the absorption tower 1 by utilizing the height difference for further recovery of methanol.

[0025] Preferably, the upper section of the absorption tower 1, the middle section of the absorption tower 1, and the lower section of the absorption tower 1 are each provided with a VOC value device. The VOC value device is as described above and will not be described in detail here. The VOC value device can monitor the VOC value in the absorption tower 1 in real time, and the amount of desalted water and the liquid level height of the liquid seal tank 1 and / or the liquid seal tank 2 can be adjusted according to the VOC value.

[0026] The detection of the VOC value can also be performed manually according to specific conditions. The skilled person can make appropriate selection according to specific conditions, which is not limited by the applicant.

[0027] Embodiment Three

[0028] The present embodiment provides a specific application scenario:

[0029] The breathing gas (tail gas) in the tank area is derived from the breathing gas of the refined methanol tank, the breathing gas of the crude methanol tank, and the breathing gas of the fusel alcohol tank, and the total amount is: 700m 3 / h;

[0030] The volatile gas (tail gas) in the loading area is derived from the volatile gas of the refined methanol loading station and the volatile gas of the fusel alcohol loading station, and the total amount is: 547m 3 / h;

[0031] The operating flexibility of the present embodiment is 50%-110%. The breathing gas in the tank area passes through the liquid seal tank 2, the volatile gas in the loading area passes through the liquid seal tank 1, and the breathing gas in the tank area and the volatile gas in the loading area are mixed in the pipeline mixer and then enter the lower part of the absorption tower 1. The two sections of packing and four layers of flexible trays in the absorption tower 1 are fully contacted with water from the top of the tower to absorb the methanol components in the tail gas. The gas at the top of the absorption tower 1 is sent to the RTO (regenerative thermal oxidizer). In the present embodiment, the methanol content in the gas at the top of the tower is less than 50mg / m 3 (the oxygen content is 3%), and the non-methane total hydrocarbon content is less than 60mg / m 3 (non-combustion method). The tail gas in the present embodiment meets the emission standard and is discharged into the atmosphere. Part of the wastewater from the tower bottom is recycled and re-entered into the lower section of the packing section, and the other part of the wastewater flows out of the tower bottom and is used as an extractant in the methanol rectification process. In the present embodiment, the discharge amount of the wastewater from the tower bottom is less than 8m 3 / h.

[0032] As described above, the present application has the following advantages due to the use of the above technical solutions:

[0033] (1) The breathing gas in the methanol rectification tank area and the volatile gas in the loading area can meet the emission standard;

[0034] (2) The device can handle no waste liquid discharge, and the liquid from the tower bottom is sent to the subsequent crude methanol rectification section as an extractant, which improves the recovery rate of methanol and reduces the loss of methanol.

[0035] (3) The device blocks the safety problem of the front and rear devices, avoiding affecting the front and rear devices; specifically, the setting of the liquid seal tank can block the connection with the front device, playing a role of not affecting the front working condition, further ensuring the safe operation of the device; preferably, the setting of the explosion-proof fan and the flame arrester can block the connection with the rear device, playing a role of not affecting the rear working condition; the present application greatly reduces the safety correlation problem with the front and rear devices, and can be applied to various working conditions, and solves the problem of safety in various working conditions of low and high VOCs concentration of methanol.

[0036] The devices and connection relationships not specifically described above all belong to the prior art, and the present application will not be specifically described here.

[0037] The preferred mode of the present application is described in detail above in combination with the drawings, but the present application is not limited to the specific details in the above embodiments, and various simple modifications can be made to the technical solutions of the present application within the technical concept of the present application, and these simple modifications all belong to the protection scope of the present application.

[0038] In addition, it should be noted that each specific technical feature described in the above specific embodiments can be combined in any appropriate manner without contradiction, and various possible combinations of the present application will not be described again in order to avoid unnecessary repetition.

[0039] In addition, various different embodiments of the present application can also be combined in any manner, as long as they do not deviate from the idea of the present application, and the application should also be considered as disclosed content of the present application.

Claims

1. A methanol VOCs gas treatment apparatus comprising an absorption column (1), characterized in that, The absorption tower (1) is connected with a desalted water pipeline (5) and a liquid seal device on one side, the bottom of the absorption tower (1) is connected with the input end of a cooler (7), the output end of the cooler (7) is connected with a production pipeline (10), the production pipeline (10) is connected with a circulation pipeline (11), the circulation pipeline (11) is connected with the absorption tower (1), and the top of the absorption tower (1) is connected with an exhaust pipeline (16).

2. The methanol VOCs gas treatment device according to claim 1, wherein, The exhaust pipeline (16) is provided with a flame arrester (17), and the rear part of the flame arrester (17) is provided with an anti-explosion fan.

3. A methanol VOCs gas treatment device according to claim 2, characterized in that, The anti-explosion fan comprises an anti-explosion fan one (18) and an anti-explosion fan two (19) arranged in parallel.

4. The methanol VOCs gas treatment device of claim 1, wherein, The desalted water pipeline (5) is connected with one end of a desalted pipeline one (6), and the other end of the desalted pipeline one (6) is connected with the absorption tower (1).

5. The methanol VOCs gas treatment device of claim 1, wherein, The liquid seal device comprises a liquid seal tank one (20) and a liquid seal tank two (21), one side of the liquid seal tank one (20) is connected with an air inlet pipeline one (22), the air inlet pipeline one (22) is connected with a cooler one (23), the top of the liquid seal tank one (20) is connected with the absorption tower (1) through a top pipeline one (24), and the bottom of the liquid seal tank one (20) is connected with the absorption tower (1) through a liquid seal tank one tower kettle pipeline (25); one side of the liquid seal tank two (21) is connected with an air inlet pipeline two (26), the air inlet pipeline two (26) is connected with a cooler two (27), the top of the liquid seal tank two (21) is connected with the absorption tower (1) through a top pipeline two (28), and the bottom of the liquid seal tank two (21) is connected with the absorption tower (1) through a liquid seal tank two tower kettle pipeline (29).

6. The methanol VOCs gas treatment device of claim 5, wherein, The top pipeline two (28) communicates with the top pipeline one (24).

7. The methanol VOCs gas treatment device of claim 5, wherein, The liquid seal tank two tower kettle pipeline (29) communicates with the liquid seal tank one tower kettle pipeline (25).

8. The methanol VOCs gas treatment device of claim 1, wherein, The bottom of the absorption tower (1) is connected with the input end of the cooler (7) through a production pipeline one (12), the production pipeline one (12) is provided with a rich liquid production pump one (13), the production pipeline one (12) is provided with a production pipeline two (14) in parallel, and the production pipeline two (14) is provided with a rich liquid production pump two (15).

9. The methanol VOCs gas treatment device of claim 1, wherein, The middle part of the absorption tower (1) is provided with a tower middle cooler (2), and the tower middle cooler (2) is connected with a cooling water inlet pipeline (3) and a cooling water return pipeline (4).

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