Non-stop online cleaning device for salt-containing NMP (N-Methyl Pyrrolidone) wastewater rectifying tower reboiler

Abstract

The utility model provides a non-stop online cleaning device for a salt-containing NMP wastewater rectifying tower reboiler, the device comprises a stock solution tank, a reduced-pressure rectifying mechanism and a normal-pressure rectifying mechanism, the reduced-pressure rectifying mechanism comprises a reduced-pressure rectifying tower and a reduced-pressure reboiler, the normal-pressure rectifying mechanism comprises a normal-pressure rectifying tower and a normal-pressure reboiler, and the normal-pressure rectifying tower and the normal-pressure reboiler are connected with the stock solution tank. A liquid outlet of the stock solution tank is communicated with a first inlet of the normal-pressure rectifying tower through a first main pipeline and a second branch pipeline, the normal-pressure reboiler is communicated with a third inlet of the normal-pressure rectifying tower, and an outlet of the normal-pressure rectifying tower is communicated with an inlet of the normal-pressure reboiler through a third main pipeline and a fifth branch pipeline in sequence; when the reboiler is cleaned, a stock solution enters the normal-pressure rectifying tower from the stock solution tank, the stock solution enters the normal-pressure reboiler to be flushed under the condition that a fifth valve and a sixth valve are opened, part of the stock solution returns to the stock solution tank, shutdown is not needed, and extra water is not needed. And extra wastewater is avoided.

Description

Technical Field

[0001] The present disclosure relates to the technical field of waste battery recycling and treatment, and in particular to an online cleaning device for a reboiler of a salt-containing NMP wastewater distillation tower without shutting down the machine. Background Art

[0002] The distillation device is used to separate and purify the components to be separated. During the distillation process, the reboiler is prone to salt accumulation, which affects the heat exchange efficiency and even blocks the pipes. If the reboiler is shut down and disassembled for flushing, it will be very time-consuming and labor-intensive.

[0003] In order to solve the above problems, the prior art such as CN215310280U discloses a distillation tower that can clean the reboiler without stopping the distillation tower. A material input pipe is provided in the middle of the right side of the distillation tower 1. The lower part of the distillation tower 1 is connected with a double heater structure, and the double heater structure is connected with a circulating water washing mechanism. The circulating water washing mechanism includes a water washing liquid tank 14, a high-pressure water supply pump 15, a flushing water supply pipe 16 and a reflux water pipe 17. The water pumping end of the high-pressure water supply pump 15 is connected to the water washing liquid tank 14, and one end of the flushing water supply pipe 16 is connected to the high-pressure water supply pump 15. The water delivery end of the water delivery pump 15 is connected, and the other end thereof is connected to the upper connecting pipes of the heater 1 11 and the heater 2 12 respectively through two groups of branch pipes, and the connection point position of the two groups of branch pipes on the upper side is located at the lower side of the upper valve 111 and the upper valve 2 121. One end of the return water pipe 17 is connected to the lower connecting pipes of the heater 1 11 and the heater 2 12 through two groups of branch pipes, and the other end thereof is connected to the upper part of the inner cavity of the washing liquid tank 14, and the connection point position of the two groups of branch pipes on the lower side is located above the lower valve 112 and the lower valve 2 122.

[0004] The above-mentioned device is equipped with a dual heater structure, one for use and one for backup. When cleaning the heater, the backup unit can be switched for use, without stopping the machine for heater cleaning, thereby ensuring the continuous and stable operation of the distillation tower. By setting a circulating water washing mechanism, the heater can be flushed without disassembling it, and the circulating flushing mode also reduces the waste of water resources, so that the device can be cleaned online without stopping.

[0005] Similarly, in the process of lithium battery manufacturing, some waste battery slurry will be produced, which contains N-methylpyrrolidone (NMP). When the battery powder in the slurry is recovered by wet method, a large amount of salt-containing NMP wastewater will be produced. The salt content of the wastewater is about 0.5%, which needs to be distilled. During the distillation process, the reboiler is prone to salt accumulation, which affects the heat exchange efficiency and even blocks the pipe. If the reboiler is shut down and disassembled for flushing, the whole process is very time-consuming and labor-intensive.

[0006] However, if a circulating water washing mechanism is used for flushing as in the above-mentioned device, although there is no need to shut down the machine, additional water is required when using the circulating water washing mechanism, thereby generating additional wastewater that is difficult to handle. Utility Model Content

[0007] The purpose of the present invention is to overcome the shortcomings of the prior art and provide an online cleaning device for a reboiler of a salt-containing NMP wastewater distillation tower without stopping the machine and avoiding the generation of additional wastewater and the problem of being difficult to treat.

[0008] The purpose of this disclosure is achieved through the following technical solutions:

[0009] An online cleaning device for a reboiler of a salt-containing NMP wastewater distillation tower without stopping the machine, comprising:

[0010] Liquid tank;

[0011] A vacuum distillation mechanism, comprising a vacuum distillation tower and a vacuum reboiler, wherein the liquid outlet of the raw liquid tank is connected to a first branch pipeline through a first main pipeline, the first branch pipeline is connected to a first inlet of the vacuum distillation tower, the first branch pipeline is provided with a first valve, the outlet of the vacuum distillation tower is connected to a second main pipeline, the second main pipeline is connected to the inlet of the vacuum reboiler through a third branch pipeline, the outlet of the vacuum reboiler is connected to a second inlet of the vacuum distillation tower, and the third branch pipeline is provided with a second valve;

[0012] The atmospheric distillation mechanism comprises an atmospheric distillation tower and an atmospheric reboiler, wherein the first main pipeline is also connected to the second branch pipeline, the second branch pipeline is connected to the first inlet of the atmospheric distillation tower, the second branch pipeline is provided with a third valve, the second main pipeline is also connected to the second inlet of the atmospheric distillation tower through a fourth branch pipeline, the fourth branch pipeline is provided with a fourth valve, the atmospheric reboiler is connected to the third inlet of the atmospheric distillation tower, the outlet of the atmospheric distillation tower is connected to the inlet of the atmospheric reboiler through the third main pipeline and the fifth branch pipeline in sequence, the fifth branch pipeline is provided with a fifth valve, the outlet of the atmospheric distillation tower is also connected to the sixth branch pipeline through the third main pipeline, the sixth branch pipeline is connected to the liquid inlet of the raw liquid tank, and the sixth branch pipeline is provided with a sixth valve.

[0013] In one of the embodiments, the first main pipeline is provided with a first mechanical pump.

[0014] In one of the embodiments, the second main pipeline is provided with a second mechanical pump.

[0015] In one of the embodiments, the third main pipeline is provided with a third mechanical pump.

[0016] In one embodiment, the vacuum distillation tower includes a vacuum tower top and a vacuum tower bottom connected to each other, the liquid outlet of the raw liquid tank is connected to the vacuum tower top through the first main pipeline and the first branch pipeline in sequence, the vacuum tower bottom is connected to the vacuum reboiler through the second main pipeline and the third branch pipeline in sequence, and the vacuum tower bottom is also connected to the atmospheric distillation tower through the second main pipeline and the fourth branch pipeline in sequence.

[0017] In one embodiment, the vacuum tower top is provided with a first tower plate, and the first tower plate is arranged on the inner side wall of the vacuum tower top.

[0018] In one embodiment, the vacuum reboiler includes a first shell top, a first heating element and a first shell bottom connected in sequence, the first shell top is connected to the vacuum tower kettle, and the vacuum tower kettle is connected to the first shell bottom through the second main pipeline and the third branch pipeline in turn.

[0019] In one embodiment, the atmospheric distillation tower includes an atmospheric tower top and an atmospheric tower bottom connected to each other, the liquid outlet of the raw liquid tank is connected to the atmospheric tower top through the first main pipeline and the second branch pipeline in sequence, the atmospheric tower bottom is connected to the atmospheric reboiler through the third main pipeline and the fifth branch pipeline in sequence, and the atmospheric tower bottom is also connected to the raw liquid tank through the third main pipeline and the sixth branch pipeline in sequence.

[0020] In one of the embodiments, the atmospheric tower top is provided with a second tower plate, and the second tower plate is arranged on the inner side wall of the atmospheric tower top.

[0021] In one embodiment, the atmospheric pressure reboiler includes a second shell top, a second heating element and a second shell bottom connected in sequence, the second shell top is connected to the atmospheric pressure tower kettle, and the atmospheric pressure tower kettle is connected to the second shell bottom through the third main pipeline and the fifth branch pipeline in turn.

[0022] Compared with the prior art, the present invention has at least the following advantages:

[0023] 1. The above-mentioned online cleaning device for the reboiler of the salt-containing NMP wastewater distillation tower without stopping the machine, when working, open the first valve, open the second valve and the fourth valve, open the fifth valve at the same time, close the third valve and the sixth valve, the stock liquid enters the vacuum distillation tower from the stock liquid tank, the separated liquid enters the vacuum reboiler through the second valve for evaporation, and part of the liquid enters the atmospheric distillation tower through the fourth valve and then enters the atmospheric reboiler for evaporation; when cleaning the reboiler, open the third valve, close the first valve and the fourth valve, open the fifth valve and the sixth valve at the same time, the stock liquid enters the atmospheric distillation tower from the stock liquid tank, and the stock liquid enters the atmospheric reboiler for flushing through the fifth valve, so there is no need to stop the machine.

[0024] 2. When cleaning operation is required, part of the raw liquid at the bottom of the atmospheric distillation tower is in the open state of the sixth valve, and the raw liquid after cleaning the atmospheric distillation tower and the atmospheric reboiler is returned to the raw liquid tank for circulation cleaning to avoid waste of raw liquid. At the same time, no additional water is required during the online cleaning process, avoiding the generation of additional wastewater and the problem of difficult treatment. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the technical solutions of the embodiments of the present disclosure, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present disclosure and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0026] Figure 1 Schematic diagram of the structure of an online cleaning device for a reboiler of a salt-containing NMP wastewater distillation tower without stopping the machine in one embodiment;

[0027] Figure 2 for Figure 1 The structural schematic diagram of the vacuum distillation structure in the online cleaning device for the reboiler of the salt-containing NMP wastewater distillation tower without stopping the machine is shown;

[0028] Figure 3 for Figure 1 The structural schematic diagram of the atmospheric distillation structure in the online cleaning device of the reboiler of the salt-containing NMP wastewater distillation tower without stopping the machine is shown.

[0029] Reference numerals: 10, online cleaning device; 100, raw liquid tank; 101, first valve; 102, second valve; 103, third valve; 104, fourth valve; 105, fifth valve; 106, sixth valve;

[0030] 107, intake valve; 108, first mechanical pump; 109, second mechanical pump; 110, third mechanical pump;

[0031] 200, vacuum distillation mechanism; 210, vacuum distillation tower; 211, vacuum tower top; 2111, first tower plate;

[0032] 212, vacuum tower kettle; 220, vacuum reboiler; 221, first shell top; 222, first heating element; 223, first shell bottom; 300, atmospheric distillation mechanism; 310, atmospheric distillation tower; 311, atmospheric tower top; 3111, second tower plate; 312, atmospheric tower kettle; 320, atmospheric reboiler; 321, second shell top; 322, second heating element; 323, second shell bottom. DETAILED DESCRIPTION

[0033] In order to facilitate the understanding of the present disclosure, the present disclosure will be described more fully below with reference to the relevant drawings. The preferred embodiments of the present disclosure are given in the drawings. However, the present disclosure can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the disclosure of the present disclosure more thoroughly and comprehensively understood.

[0034] It should be noted that when an element is referred to as being "fixed to" another element, it may be directly on the other element or there may also be a centered element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a centered element at the same time. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which the present disclosure belongs. The terms used herein in the specification of the present disclosure are only for the purpose of describing specific embodiments and are not intended to limit the present disclosure. The term "and / or" used herein includes any and all combinations of one or more related listed items.

[0035] In order to better understand the technical solutions and beneficial effects of the present invention, the present invention is further described in detail below in conjunction with specific embodiments:

[0036] like Figure 1 As shown, an online cleaning device 10 for a reboiler of a salt-containing NMP wastewater distillation tower without stopping the machine is used to distill a raw liquid or perform a cleaning operation using the raw liquid. Specifically, the raw liquid is salt-containing NMP wastewater. In one embodiment, the online cleaning device 10 includes a raw liquid tank 100, a vacuum distillation mechanism 200, and a normal pressure distillation mechanism 300.

[0037] The vacuum distillation mechanism 200 includes a vacuum distillation tower 210 and a vacuum reboiler 220. The liquid outlet of the raw liquid tank 100 is connected to the first branch pipeline through the first main pipeline, the first branch pipeline is connected to the first inlet of the vacuum distillation tower 210, the first branch pipeline is provided with a first valve 101, the outlet of the vacuum distillation tower 210 is connected to the second main pipeline, the second main pipeline is connected to the inlet of the vacuum reboiler 220 through the third branch pipeline, the outlet of the vacuum reboiler 220 is connected to the second inlet of the vacuum distillation tower 210, and the third branch pipeline is provided with a second valve 102;

[0038] The atmospheric distillation mechanism 300 includes an atmospheric distillation tower 310 and an atmospheric reboiler 320. The first main pipeline is also connected to the second branch pipeline, the second branch pipeline is connected to the first inlet of the atmospheric distillation tower 310, the second branch pipeline is provided with a third valve 103, the second main pipeline is also connected to the second inlet of the atmospheric distillation tower 310 through the fourth branch pipeline, the fourth branch pipeline is provided with a fourth valve 104, the atmospheric reboiler 320 is connected to the third inlet of the atmospheric distillation tower 310, the outlet of the atmospheric distillation tower 310 is connected to the inlet of the atmospheric reboiler 320 through the third main pipeline and the fifth branch pipeline in turn, the fifth branch pipeline is provided with a fifth valve 105, the outlet of the atmospheric distillation tower 310 is also connected to the sixth branch pipeline through the third main pipeline, the sixth branch pipeline is connected to the liquid inlet of the raw liquid tank 100, the sixth branch pipeline is provided with a sixth valve 106, the air inlet of the atmospheric reboiler 320 is connected to the air inlet pipeline for receiving external steam, and the air inlet pipeline is provided with an air inlet valve 107.

[0039] Among them, the first inlet of the vacuum distillation tower 210 is located above the second inlet, and the outlet of the vacuum distillation tower 210 is located at the bottom, which is convenient for the subsequent reboiling step of the raw liquid; the second inlet of the atmospheric distillation tower 310 is located above the first inlet, the first inlet is located above the third inlet, and the outlet of the atmospheric distillation tower 310 is located at the bottom, which is convenient for the subsequent reboiling or cleaning steps of the raw liquid.

[0040] Furthermore, the first valve 101 is used to control whether the raw liquid in the raw liquid tank 100 flows to the vacuum distillation tower 210, the second valve 102 is used to control whether the separated liquid flows to the vacuum reboiler 220, the third valve 103 is used to control whether the raw liquid in the raw liquid tank 100 flows to the atmospheric distillation tower 310, the fourth valve 104 is used to control whether the separated liquid flows to the atmospheric distillation tower 310, the fifth valve 105 is used to control whether the separated liquid flows to the atmospheric reboiler 320, the sixth valve 106 is used to control whether the separated liquid flows to the raw liquid tank 100, and the air intake valve 107 is used to control whether external steam enters the atmospheric reboiler 320.

[0041] In this embodiment, when the device performs evaporation separation, the first valve 101 is opened and the third valve 103 is closed, the second valve 102 and the fourth valve 104 are opened, the air inlet valve 107 is opened, the sixth valve 106 is closed and the fifth valve 105 is opened. At this time, the raw liquid in the raw liquid tank 100 will pass through the first main pipeline and the first branch pipeline in sequence, and then enter the interior of the vacuum distillation tower 210 from the first inlet of the vacuum distillation tower 210. After the raw liquid is separated by components, the liquid settled at the bottom of the vacuum distillation tower 210 passes through the second main pipeline and the third branch pipeline in sequence from the outlet of the vacuum distillation tower 210, and then enters the vacuum distillation tower 210 through the inlet of the vacuum reboiler 220. The vacuum reboiler 220 is used for the liquid to evaporate in the vacuum reboiler 220, and part of the liquid is returned to the vacuum distillation tower 210 from the outlet of the vacuum reboiler 220 through the second inlet of the vacuum distillation tower 210 to perform the circulation step; the liquid in the second main pipeline also passes through the fourth branch pipeline and enters the interior of the atmospheric distillation tower 310 from the second inlet of the atmospheric distillation tower 310. After secondary separation, the liquid settled at the bottom of the atmospheric distillation tower 310 passes through the third main pipeline and the fifth branch pipeline in sequence from the outlet of the atmospheric distillation tower 310, and enters the interior of the atmospheric reboiler 320 from the inlet of the atmospheric reboiler 320, and then the liquid evaporates in the atmospheric reboiler 320.

[0042] In another embodiment, when the device is undergoing a cleaning operation, the third valve 103 is opened and the first valve 101 is closed, the second valve 102 is opened and the fourth valve 104 is closed, the air inlet valve 107 is closed, and the fifth valve 105 and the sixth valve 106 are opened. At this time, the raw liquid in the raw liquid tank 100 will sequentially pass through the first main pipeline and the second branch pipeline and enter from the first inlet of the atmospheric distillation tower 310. Subsequently, the liquid passes through the third main pipeline and the fifth branch pipeline from the atmospheric distillation tower 310 and sequentially enters the atmospheric reboiler 320 from the inlet of the atmospheric reboiler 320 for cleaning. During this period, the raw liquid in the third main pipeline also returns to the raw liquid tank 100 through the sixth branch pipeline for circulating flushing, while another part of the raw liquid enters the atmospheric reboiler 320 and then returns to the atmospheric distillation tower 310 from the outlet of the atmospheric reboiler 320 through the third inlet of the atmospheric distillation tower 310. In this way, the raw liquid can be used to clean the atmospheric reboiler 320 without stopping the machine, and no additional water is required.

[0043] In one embodiment, the first main pipeline is provided with a first mechanical pump 108, specifically, the first mechanical pump 108 is a raw liquid tank outlet pump, and the raw liquid tank outlet pump is used to transport the raw liquid in the raw liquid tank 100 to the vacuum distillation tower 210 when the first valve 101 is in an open state and the third valve 103 is in a closed state. Further, when the device performs evaporation separation, the first valve 101 is opened and the third valve 103 is closed, and the raw liquid tank outlet pump pushes the raw liquid in the raw liquid tank 100 into the vacuum distillation tower 210 for the next separation operation.

[0044] In another embodiment, the raw liquid tank outlet pump is used to transport the raw liquid in the raw liquid tank 100 to the atmospheric distillation tower 310 when the third valve 103 is in an open state and the first valve 101 is in a closed state. Further, when the device performs a cleaning operation, the third valve 103 is opened and the first valve 101 is closed, and the raw liquid tank outlet pump pushes the raw liquid in the raw liquid tank 100 into the atmospheric distillation tower 310 for subsequent cleaning operations.

[0045] In one embodiment, the second main pipeline is provided with a second mechanical pump 109, specifically, the second mechanical pump 109 is a vacuum distillation tower kettle pump, and the vacuum distillation tower kettle pump is used to transport the liquid in the vacuum distillation tower 210 to the vacuum reboiler 220 and the atmospheric distillation tower 310 respectively when the second valve 102 and the fourth valve 104 are both in the open state. Further, when the device performs evaporation separation, the second valve 102 and the fourth valve 104 are opened, and the vacuum distillation tower kettle pump pushes the liquid in the vacuum distillation tower 210 into the vacuum reboiler 220 to evaporate the liquid, and part of the liquid is pushed into the atmospheric distillation tower 310 for subsequent liquid evaporation.

[0046] In another embodiment, when the second valve 102 is in an open state and the fourth valve 104 is in a closed state, the raw liquid cannot enter the vacuum distillation tower 210 because the first valve 101 is already closed, the vacuum reboiler 220 does not work, and thus the vacuum distillation tower bottom pump does not work.

[0047] In one embodiment, the third main pipeline is provided with a third mechanical pump 110, specifically, the third mechanical pump 110 is a tower bottom pump of the atmospheric distillation tower, and the tower bottom pump of the atmospheric distillation tower is used to transport the liquid in the atmospheric distillation tower 310 to the atmospheric reboiler 320 when the fifth valve 105 is in an open state and the sixth valve 106 is in a closed state. Further, when the device performs evaporation separation, the fifth valve 105 is opened, the sixth valve 106 is closed, and the tower bottom pump of the atmospheric distillation tower pushes the liquid in the atmospheric distillation tower 310 into the atmospheric reboiler 320 to evaporate the liquid.

[0048] In another embodiment, the atmospheric distillation tower kettle pump is used to transport the liquid in the atmospheric distillation tower 310 to the atmospheric reboiler 320 and the raw liquid tank 100 respectively when the fifth valve 105 and the sixth valve 106 are both in an open state. Specifically, the liquid in the atmospheric distillation tower 310 is water that has been separated by components. Further, when the device performs a cleaning operation, the fifth valve 105 and the sixth valve 106 are opened, and the atmospheric distillation tower kettle pump pushes the liquid in the atmospheric distillation tower 310 into the atmospheric reboiler 320 to clean the atmospheric reboiler 320, and at the same time, part of the liquid is pushed into the raw liquid tank 100 to perform a cyclic cleaning operation.

[0049] like Figure 2 As shown, in one embodiment, the vacuum distillation tower 210 includes a vacuum tower top 211 and a vacuum tower bottom 212 connected to each other. The liquid outlet of the raw liquid tank 100 is connected to the vacuum tower top 211 through the first main pipeline and the first branch pipeline in sequence, so that the raw liquid can undergo the next step of raw liquid component separation after entering the vacuum tower top 211. The vacuum tower bottom 212 is connected to the vacuum reboiler 220 through the second main pipeline and the third branch pipeline in sequence to evaporate the liquid or clean the vacuum reboiler 220. When performing evaporation separation, the vacuum tower bottom 212 is also connected to the normal pressure distillation tower 310 through the second main pipeline and the fourth branch pipeline in sequence to perform secondary separation and evaporation of the liquid.

[0050] It can be understood that the vacuum distillation tower 210 is mainly used to separate the components of the raw liquid. The separated liquid is located at the bottom of the vacuum distillation tower 210, i.e., the vacuum tower bottom 212, and other components such as NMP, sodium sulfate, etc. are located in the vacuum tower top 211, thus achieving a separation effect.

[0051] In one embodiment, the vacuum tower top 211 is provided with a first tower plate 2111, and the first tower plate 2111 is arranged on the inner side wall of the vacuum tower top 211, so that the raw liquid passes through the first tower plate 2111 and enters the vacuum tower kettle 212 after separation. It can be understood that the first tower plate 2111 is installed on the inner side of the vacuum tower top 211, and is used to separate the raw liquid by evaporation, and the separated water enters the vacuum tower kettle 212 for subsequent operations, and other components such as NMP, sodium sulfate, etc. are located in the first tower plate 2111 for isolation. In this embodiment, the number of the first tower plates 2111 is multiple.

[0052] In one embodiment, the vacuum reboiler 220 includes a first shell top 221, a first heating element 222 and a first shell bottom 223 connected in sequence, the first shell top 221 is connected to the vacuum tower bottom 212, and the vacuum tower bottom 212 is connected to the first shell bottom 223 through the second main pipeline and the third branch pipeline in turn, wherein the first heating element 222 can be used to evaporate the liquid, specifically, the first heating element 222 is a reboiler tube bundle.

[0053] It can be understood that the separated liquid enters the first shell bottom 223 through the second main pipeline and the third branch pipeline in sequence to perform evaporation operation or cleaning operation. Specifically, when the first heating element 222, that is, the reboiler tube bundle, is working, the liquid is evaporated, and the steam passes through the first heating element 222 and then attaches to the first shell top 221, and part of the steam returns to the vacuum distillation tower 210; when cleaning the vacuum reboiler 220, the liquid passes through the first shell bottom 223, the first heating element 222 and the first shell top 221 in sequence and then returns to the vacuum distillation tower 210.

[0054] like Figure 3As shown, in one embodiment, the atmospheric distillation tower 310 includes an atmospheric tower top 311 and an atmospheric tower bottom 312 connected to each other, and the liquid outlet of the raw liquid tank 100 is connected to the atmospheric tower top 311 through the first main pipeline and the second branch pipeline in sequence for subsequent cleaning operations, and the atmospheric tower bottom 312 is connected to the atmospheric reboiler 320 through the third main pipeline and the fifth branch pipeline in sequence. When performing the cleaning operation, the atmospheric tower bottom 312 is also connected to the raw liquid tank 100 through the third main pipeline and the sixth branch pipeline in sequence for a circulating cleaning operation without the need to add additional water for cleaning.

[0055] In one embodiment, the atmospheric tower top 311 is provided with a second tower plate 3111, and the second tower plate 3111 is arranged on the inner side wall of the atmospheric tower top 311, so that the raw liquid can enter the atmospheric tower bottom 312 after separation through the second tower plate 3111. It can be understood that the second tower plate 3111 is used to separate the raw liquid into components, and the separated water enters the atmospheric tower bottom 312 for subsequent operations, and the other components are located in the second tower plate 3111 for isolation; in addition, when the raw liquid is separated and evaporated, the second tower plate 3111 is used to perform secondary separation on the separated liquid for subsequent liquid evaporation. In this embodiment, the number of the second tower plates 3111 is multiple.

[0056] In one embodiment, the atmospheric pressure reboiler 320 includes a second shell top 321, a second heating element 322 and a second shell bottom 323 connected in sequence, the second shell top 321 is connected to the atmospheric pressure tower bottom 312, and the atmospheric pressure tower bottom 312 is connected to the second shell bottom 323 through a third main pipeline and a fifth branch pipeline in turn, wherein the second heating element 322 can be used to evaporate the liquid, specifically, the second heating element 322 is a reboiler tube bundle.

[0057] It can be understood that the separated liquid enters the second shell bottom 323 through the third main pipeline and the fifth branch pipeline in sequence to perform evaporation operation or cleaning operation. Specifically, when the second heating element 322, that is, the reboiler tube bundle, is working, the liquid is evaporated, and the steam passes through the second heating element 322 and then attaches to the second shell top 321, and part of the steam returns to the atmospheric distillation tower 310; when cleaning the atmospheric reboiler 320, the liquid passes through the second shell bottom 323, the second heating element 322 and the second shell top 321 in sequence and then returns to the vacuum distillation tower 210.

[0058] Compared with the prior art, the present invention has but is not limited to the following advantages:

[0059] 1. The above-mentioned online cleaning device 10 for the reboiler of the salt-containing NMP wastewater distillation tower without stopping the machine, when working, open the first valve 101, open the second valve 102 and the fourth valve 104, open the fifth valve 105 at the same time, close the third valve 103 and the sixth valve 106, the raw liquid enters the vacuum distillation tower 210 from the raw liquid tank 100, the separated liquid enters the vacuum reboiler 220 through the second valve 102 for evaporation, and part of the liquid enters the atmospheric distillation tower 310 through the fourth valve 104 and then enters the atmospheric reboiler 320 for evaporation; when cleaning the reboiler, open the third valve 103, close the first valve 101 and the fourth valve 104, and open the fifth valve 105 and the sixth valve 106 at the same time, the raw liquid enters the atmospheric distillation tower 310 from the raw liquid tank 100, and the raw liquid enters the atmospheric reboiler 320 for flushing through the fifth valve 105, so there is no need to stop the machine.

[0060] 2. When cleaning operation is required, part of the raw liquid at the bottom of the atmospheric distillation tower 310 is in the open state of the sixth valve 106, and the raw liquid after cleaning the atmospheric distillation tower 210 and the atmospheric reboiler 320 is returned to the raw liquid tank 100 for circulation cleaning to avoid waste of raw liquid. At the same time, no additional water is required during the online cleaning process, avoiding the generation of additional wastewater and the problem of difficult treatment.

[0061] The above-mentioned embodiments only express several implementation methods of the present disclosure, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the disclosed patent. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present disclosure, and these all belong to the protection scope of the present disclosure. Therefore, the protection scope of the disclosed patent shall be subject to the attached claims.

Claims

1. An online cleaning device (10) for a reboiler of a salt-containing NMP wastewater distillation tower without stopping the machine, characterized in that: include: Raw liquid tank (100); A vacuum distillation mechanism (200), comprising a vacuum distillation tower (210) and a vacuum reboiler (220), wherein the liquid outlet of the raw liquid tank (100) is connected to a first branch pipeline via a first main pipeline, the first branch pipeline is connected to a first inlet of the vacuum distillation tower (210), the first branch pipeline is provided with a first valve (101), the outlet of the vacuum distillation tower (210) is connected to a second main pipeline, the second main pipeline is connected to an inlet of the vacuum reboiler (220) via a third branch pipeline, the outlet of the vacuum reboiler (220) is connected to a second inlet of the vacuum distillation tower (210), and the third branch pipeline is provided with a second valve (102); The atmospheric distillation mechanism (300) comprises an atmospheric distillation tower (310) and an atmospheric reboiler (320), wherein the first main pipeline is also connected to a second branch pipeline, the second branch pipeline is connected to a first inlet of the atmospheric distillation tower (310), the second branch pipeline is provided with a third valve (103), the second main pipeline is also connected to a second inlet of the atmospheric distillation tower (310) through a fourth branch pipeline, the fourth branch pipeline is provided with a fourth valve (104), the atmospheric reboiler (320) ) is connected to the third inlet of the atmospheric distillation tower (310), the outlet of the atmospheric distillation tower (310) is connected to the inlet of the atmospheric reboiler (320) through the third main pipeline and the fifth branch pipeline in sequence, the fifth branch pipeline is provided with a fifth valve (105), the outlet of the atmospheric distillation tower (310) is also connected to the sixth branch pipeline through the third main pipeline, the sixth branch pipeline is connected to the liquid inlet of the raw liquid tank (100), and the sixth branch pipeline is provided with a sixth valve (106).

2. The online cleaning device (10) for the reboiler of the salt-containing NMP wastewater distillation tower without stopping the machine according to claim 1, characterized in that: The first main pipeline is provided with a first mechanical pump (108).

3. The online cleaning device (10) for the reboiler of the salt-containing NMP wastewater rectification tower without stopping the machine according to claim 1, characterized in that: The second main pipeline is provided with a second mechanical pump (109).

4. The online cleaning device (10) for the reboiler of the salt-containing NMP wastewater rectification tower without stopping the machine according to claim 1, characterized in that: The third main pipeline is provided with a third mechanical pump (110).

5. The online cleaning device (10) for the reboiler of the salt-containing NMP wastewater rectification tower without stopping the machine according to claim 1, characterized in that: The vacuum distillation tower (210) comprises a vacuum tower top (211) and a vacuum tower bottom (212) connected to each other; the liquid outlet of the raw liquid tank (100) is connected to the vacuum tower top (211) via the first main pipeline and the first branch pipeline in sequence; the vacuum tower bottom (212) is connected to the vacuum reboiler (220) via the second main pipeline and the third branch pipeline in sequence; the vacuum tower bottom (212) is also connected to the atmospheric distillation tower (310) via the second main pipeline and the fourth branch pipeline in sequence.

6. The online cleaning device (10) for the reboiler of the salt-containing NMP wastewater distillation tower without stopping the machine according to claim 5, characterized in that: The vacuum tower top (211) is provided with a first tower plate (2111), and the first tower plate (2111) is arranged on the inner side wall of the vacuum tower top (211).

7. The online cleaning device (10) for the reboiler of the salt-containing NMP wastewater rectification tower without stopping the machine according to claim 5, characterized in that: The vacuum reboiler (220) comprises a first shell top (221), a first heating element (222) and a first shell bottom (223) connected in sequence, wherein the first shell top (221) is connected to the vacuum tower kettle (212), and the vacuum tower kettle (212) is connected to the first shell bottom (223) via the second main pipeline and the third branch pipeline in sequence.

8. The online cleaning device (10) for the reboiler of the salt-containing NMP wastewater rectification tower without stopping the machine according to claim 1, characterized in that: The atmospheric distillation tower (310) includes an atmospheric tower top (311) and an atmospheric tower bottom (312) connected to each other. The liquid outlet of the raw liquid tank (100) is connected to the atmospheric tower top (311) via the first main pipeline and the second branch pipeline in sequence. The atmospheric tower bottom (312) is connected to the atmospheric reboiler (320) via the third main pipeline and the fifth branch pipeline in sequence. The atmospheric tower bottom (312) is also connected to the raw liquid tank (100) via the third main pipeline and the sixth branch pipeline in sequence.

9. The online cleaning device (10) for the reboiler of the salt-containing NMP wastewater rectification tower without stopping the machine according to claim 8, characterized in that: The atmospheric tower top (311) is provided with a second tower plate (3111), and the second tower plate (3111) is arranged on the inner side wall of the atmospheric tower top (311).

10. The online cleaning device (10) for the reboiler of the salt-containing NMP wastewater rectification tower without stopping the machine according to claim 8, characterized in that: The atmospheric pressure reboiler (320) comprises a second shell top (321), a second heating element (322) and a second shell bottom (323) connected in sequence, wherein the second shell top (321) is connected to the atmospheric pressure tower kettle (312), and the atmospheric pressure tower kettle (312) is connected to the second shell bottom (323) via the third main pipeline and the fifth branch pipeline in sequence.

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