Emptying and condensate draining system for waste gas recovery of ethylene glycol device

Abstract

The utility model relates to an ethylene glycol device waste gas recovery emptying condensate drain system which comprises a waste gas recovery tank, the top of one side of the waste gas recovery tank is connected with a regeneration tower through a pipeline, a waste water VOC stripping tower is located above the regeneration tower, and the waste water VOC stripping tower is connected to the top of the waste gas recovery tank through a pipeline; a reboiler group is arranged beside the waste gas recovery tank below the regeneration tower and is connected to the top of the waste gas recovery tank through a main pipe; a steam extinguishing and water collecting process is added at a high-point vent nozzle of the waste gas recovery tank, so that the waste gas emission at the vent nozzle can be effectively reduced, and the environmental pollution caused by the waste gas emission under abnormal conditions is reduced; meanwhile, technical improvement is further carried out in the steam extinguishing and water collecting process, condensate is discharged to a ground floor drain through a pipeline, condensate recycling is achieved, water vapor azeotropy is avoided, therefore, the process waste gas discharge amount and peculiar smell generation under the abnormal condition are reduced, and meanwhile the phenomenon that water mist entrainment is serious when process tail gas is discharged is effectively treated.

Description

Technical Field

[0001] The utility model relates to the treatment of condensate during the recovery and venting of waste gas from an ethylene glycol device in the process of preparing ethylene glycol, and specifically to a waste gas recovery, venting and condensate removal system for an ethylene glycol device, which is used to solve the technical problem of the impact of steam-water azeotropy on the environment and equipment during venting. Background Art

[0002] The KO tank for waste gas in the ethylene glycol production process is used to collect formaldehyde from the seven-effect unit in the system, formaldehyde from the wastewater VOC stripping tower, and recover hydrocarbons from the flash tank of the regeneration tower in an emergency. After gas-liquid separation, the gas phase is sent to the incinerator for combustion.

[0003] When an incinerator breaks down, the waste gas KO tank needs to be cut and vented on site. Since the waste gas KO tank has a high temperature and a large amount of water vapor, and also contains a high concentration of aldehydes, a large amount of water is vented on site, accompanied by a pungent odor, causing an environmental impact. Therefore, it is necessary to add corresponding equipment at the vent port to reduce the exhaust volume at the vent port. Especially in winter, when the water vapor content is high, the entire pipe corridor and the ground under the vent pipeline are all frozen, posing a safety hazard. Utility Model Content

[0004] In view of the above-mentioned technical defects, the purpose of the present utility model is to provide a waste gas recovery, venting and condensate removal system for an ethylene glycol device. By adding a steam extinguishing and water collection process at the high-point vent port of the waste gas recovery tank, the waste gas emission volume at the vent port can be effectively reduced, the pollution to the environment caused by waste gas emissions under abnormal circumstances can be reduced, and part of the condensate can be effectively recovered.

[0005] In order to achieve the above-mentioned object, the technical solution adopted by the present invention is: a waste gas recovery, venting and condensate removal system for an ethylene glycol device, comprising: a waste gas recovery tank, the top of one side of the waste gas recovery tank is connected to a regeneration tower through a pipeline, a wastewater VOC stripping tower is located above the regeneration tower, and the wastewater VOC stripping tower is connected to the top of the waste gas recovery tank through a pipeline; a reboiler group is arranged next to the waste gas recovery tank below the regeneration tower, and the reboiler group is connected to the top of the waste gas recovery tank through a main pipe;

[0006] The top of the other side of the waste gas recovery tank is connected to the incinerator through the incinerator connecting pipe; the root of the incinerator connecting pipe near the waste gas recovery tank is led to the venting pipeline upward, and a steam extinguishing and water collecting process is set at the high point of the venting pipeline;

[0007] Furthermore, the reboiler group includes three reboilers, which are respectively provided with a triple-effect reboiler, a quadruple-effect reboiler and a quintuple-effect reboiler from top to bottom; the three reboilers are connected to the main pipe in parallel through respective pipelines, and control valves are respectively provided on respective pipelines;

[0008] Further, the sound damper is arranged in the steam elimination and water recovery process, the sound damper is connected to the top of the venting pipeline, the sound damper can reduce the exhaust gas amount of the venting port, and the pollution caused by the exhaust gas emission to the environment in the abnormal condition of waste gas recovery can be reduced;

[0009] At the same time, when the waste gas recovery tank is vented on site, the condensate exists in the sound damper, the steam-water azeotrope appears, a large amount of water will be sprayed from the pipe gallery, and there is a safety hazard, and a large amount of peculiar smell exists on site; The further means of the scheme is that a plurality of through holes are arranged in the side wall of the sound damper, the plurality of through holes are connected to the condensate main pipe through branch pipelines respectively and are gathered on the condensate main pipe, and the end of the condensate main pipe is connected to a floor drain; Through the process, the condensate in the sound damper is discharged through the condensate main pipe and is discharged into the floor drain, so that the steam-water azeotrope is avoided.

[0010] Further, the branch pipelines connected to the side wall of the sound damper are arranged in three parallel rows from top to bottom, and control valves are arranged on each branch pipeline, so that the condensate flow can be controlled.

[0011] The process of the system adopting the above scheme is as follows:

[0012] The hydrocarbons (K-320 recovery gas compressor stops running) flashed from the top of the regenerator, the aldehyde exhaust gas of the waste water VOC stripping tower, and the venting gas of the three-effect reboiler, the four-effect reboiler and the five-effect reboiler are all sent into the waste gas recovery tank, and then are sent to the incinerator after being separated by the waste gas recovery tank, and all the organic matters are incinerated in the incinerator.

[0013] When the K-320 recovery gas compressor stops running or the incinerator is in trouble and is under maintenance, the exhaust gas of the waste gas recovery tank is discharged on site; when the waste gas recovery tank is vented on site, the condensate exists in the sound damper, the steam-water azeotrope appears, a large amount of water will be sprayed from the pipe gallery, and a large amount of peculiar smell exists on site, at this time, the control valves on the plurality of branch pipelines of the sound damper are opened, so that the condensate is gathered and directly discharged into the floor drain through the condensate main pipe, and the steam-water azeotrope is avoided.

[0014] The beneficial effects of the technical scheme of the utility model lie in that: the steam elimination and water recovery process is added at the high point of the venting port of the waste gas recovery tank, the exhaust gas amount at the venting port can be effectively reduced, and the pollution caused by the exhaust gas emission to the environment in the abnormal condition is reduced; at the same time, the steam elimination and water recovery process is further technically improved, the condensate is discharged to the floor drain through the pipeline, the condensate is recovered, the steam-water azeotrope is avoided, the exhaust gas amount and the peculiar smell in the abnormal condition are reduced, and the phenomenon of water mist entrainment in the process exhaust gas emission is effectively controlled. BRIEF DESCRIPTION OF DRAWINGS

[0015] Figure 1 It is a structural diagram of the utility model.

[0016] In the figure, 1. Waste gas recovery tank, 2. Regeneration tower C-220, 3. Wastewater VOC stripping tower C-570, 4. Main pipe, 5. Incinerator connecting pipe, 6. Vent pipeline, 7. Triple-effect reboiler E-533, 8. Quadruple-effect reboiler E-534, 9. Quintuple-effect reboiler E-535, 10. Muffler, 11. Condensate main pipe, 12. Floor drain. DETAILED DESCRIPTION

[0017] To make the above-mentioned objects, features, and advantages of the present invention more clearly understood, the following detailed description of specific embodiments of the present invention is provided in conjunction with the accompanying drawings. The following description sets forth many specific details to facilitate a full understanding of the present invention. However, the present invention can be implemented in many other ways than those described herein, and those skilled in the art may make similar modifications without departing from the scope of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0018] like Figure 1 The waste gas recovery, venting and condensate removal system for the ethylene glycol device shown in the figure includes: a waste gas recovery tank 1, the top of one side of the waste gas recovery tank 1 is connected to a regeneration tower 2 via a pipeline, a wastewater VOC stripping tower 3 is located above the regeneration tower 2, and the wastewater VOC stripping tower 3 is connected to the top of the waste gas recovery tank 1 via a pipeline; a reboiler group is set next to the waste gas recovery tank 1 below the regeneration tower 2, and the reboiler group is connected to the top of the waste gas recovery tank 1 via a main pipe 4;

[0019] The top of the other side of the waste gas recovery tank 1 is connected to the incinerator RTO through the incinerator connecting pipe 5; the root of the incinerator connecting pipe 5 near the waste gas recovery tank 1 leads to the venting pipeline 6 upward, and the high point of the venting pipeline 6 is provided with a steam extinguishing and water collecting process;

[0020] In this embodiment, specifically at the top of the 5th floor at the north end of the main corridor of the system, the water vapor content at the high point venting port of the waste gas recovery tank 1 is relatively large, so the steam extinguishing and water collection measures are used;

[0021] The reboiler group includes three reboilers, which are respectively provided with a triple-effect reboiler 7, a quadruple-effect reboiler 8 and a quintuple-effect reboiler 9 from top to bottom; the three reboilers are connected to the main pipe in parallel through their own pipelines, and control valves are respectively provided on their respective pipelines;

[0022] Furthermore, a muffler 10 is provided in the steam extinguishing and water collecting process. The muffler 10 is connected to the top of the vent line 6. The muffler 10 can reduce the amount of gas discharged from the vent port, thereby reducing the pollution caused by the exhaust gas emission to the environment in the case of abnormal exhaust gas recovery.

[0023] At the same time, when the exhaust gas recovery tank 1 is emptied on site, condensate will be present in the muffler 10, resulting in azeotropic mixture of steam and water. A large amount of water will spray down from the pipe gallery, posing a safety hazard and accompanied by a large amount of odor on site. A further measure of this solution is to open a plurality of through holes on the side wall of the muffler 10, and the plurality of through holes are respectively connected to and collected into the condensate main pipe 11 through branch pipelines, and the end of the condensate main pipe 11 is connected to the floor drain 12.

[0024] Three branch pipelines are connected to the side wall of the muffler 10 and arranged in parallel from top to bottom. A control valve is provided on each branch pipeline to facilitate the control of the condensate flow rate.

[0025] The process of the system using the above solution is:

[0026] The hydrocarbons flashed out from the first and second flashes at the top of the regeneration tower 2, the aldehyde emission gas from the wastewater VOC stripping tower 3, and the venting air from the third-effect reboiler 7, the fourth-effect reboiler 8, and the fifth-effect reboiler 9 all enter the waste gas recovery tank 1, and after liquid separation through the waste gas recovery tank 1, they are sent to the incinerator RTO, where all organic matter is incinerated;

[0027] In this embodiment, when the incinerator RTO fails for maintenance, the exhaust gas from the exhaust gas recovery tank 1 must be cut to the site for venting; when the exhaust gas recovery tank 1 is vented on site, condensate will exist in the on-site muffler 10, and steam-water azeotropy will occur. A large amount of water will spray down from the pipe gallery, accompanied by a large amount of odor on site. At this time, by opening the control valves on the multiple branch pipelines on the muffler 10, the condensate is gathered and discharged directly into the ground drain 12 through the condensate main pipe 11 to avoid water-vapor azeotropy.

[0028] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like to indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation to the present invention.

[0029] In addition, the terms "first", "second", etc. are used only for descriptive purposes and should not be construed as indicating or implying relative importance or an indicated number of technical features. Therefore, the features defined as "first", "second" can explicitly or implicitly include at least one of the features. In the description of the present application, the meaning of "a plurality of" is at least two, such as two, three, etc., unless otherwise specifically limited.

[0030] In the present application, unless otherwise specifically defined and limited, the terms "mounting", "connecting", "connecting", "fixing" and the like should be broadly understood, for example, it can be fixedly connected, or it can be detachably connected, or it can be integrated; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium, it can be the internal communication of two elements or the interaction relationship of two elements, unless otherwise specifically limited. For ordinary skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0031] In the present application, unless otherwise specifically defined and limited, the first feature is "on" or "under" the second feature. The first and second features can be in direct contact, or the first and second features can be indirectly contacted through an intermediate medium. Moreover, the first feature "above", "above" and "above" the second feature can be directly above or obliquely above the first feature, or only indicate that the horizontal height of the first feature is higher than that of the second feature. The first feature "below", "below" and "below" the second feature can be directly below or obliquely below the first feature, or only indicate that the horizontal height of the first feature is less than that of the second feature.

[0032] It should be noted that when an element is referred to as "fixed to" or "provided on" another element, it can be directly on another element or there can be a middle element. When an element is considered to be "connected" to another element, it can be directly connected to another element or there can be a middle element. The terms "vertical", "horizontal", "up", "down", "left", "right" and similar expressions used herein are only for illustrative purposes and do not represent the only embodiment.

Claims

1. An ethylene glycol device waste gas recovery, venting and condensate removal system, characterized in that: include: A waste gas recovery tank, the top of one side of the waste gas recovery tank is connected to a regeneration tower through a pipeline, and a wastewater VOC stripping tower is located above the regeneration tower, and the wastewater VOC stripping tower is connected to the top of the waste gas recovery tank through a pipeline; a reboiler group is set next to the waste gas recovery tank located below the regeneration tower, and the reboiler group is connected to the top of the waste gas recovery tank through a main pipe; the top of the other side of the waste gas recovery tank is connected to the incinerator through an incinerator connecting pipe; a venting pipeline is led out from the root of the incinerator connecting pipe near the waste gas recovery tank, and a steam extinguishing and water collecting process is set at the high point of the venting pipeline.

2. The ethylene glycol device waste gas recovery, venting and condensate removal system according to claim 1, characterized in that: The reboiler group includes three reboilers, which are respectively provided with a triple-effect reboiler, a quadruple-effect reboiler and a five-effect reboiler from top to bottom; the three reboilers are connected to the main pipe in parallel through their own pipelines, and control valves are respectively provided on their own pipelines.

3. The ethylene glycol device waste gas recovery, venting and condensate removal system according to claim 1, characterized in that: A muffler is provided in the steam extinguishing and water collecting process, and the muffler is connected to the top of the venting pipeline.

4. The ethylene glycol device waste gas recovery, venting and condensate removal system according to claim 3, characterized in that: A plurality of through holes are provided on the side wall of the muffler, and the plurality of through holes are respectively connected through branch pipelines and collected on a condensate main pipe, and an end of the condensate main pipe is connected to a floor drain.

5. The ethylene glycol device waste gas recovery, venting and condensate removal system according to claim 4, characterized in that: There are three branch pipelines connected to the side wall of the muffler in parallel from top to bottom, and each branch pipeline is provided with a control valve.

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