Methanol dehydration device for low-temperature methanol washing
By introducing nitrogen intake pipe, reboiler, filter and heat exchanger into the methanol water separation tower, combined with the agitator, the problem of low production effect of the methanol water separation tower is solved, and efficient methanol dehydration and stable operation process are achieved.
Patent Information
- Application Number
- CN202422031896.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-08-21
- Publication Date
- 2025-07-04
- Estimated Expiration
- 2034-08-21
AI Technical Summary
In the prior art, the production effect of the methanol water separation tower is not high, resulting in the methanol content in the wastewater being much higher than the calculated value and has poor stability.
Add a nitrogen intake pipe and reboiler on the side of the methanol water separation tower, set up a filter and a heat exchanger, combine with a stirring device to enhance the mass heat transfer effect, and pretreat it through a carbon dioxide separation tank, filtration and heating and pressure reduction operations.
The methanol distillation effect is improved, the methanol vapor water content is less than 0.4%, and the wastewater methanol content is less than 150PPM, avoiding the fluctuation of the gas volume under low load and ensuring the stability and cleanliness of the device.
Smart Images
Figure CN223055121U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of methanol dehydration, and particularly to a methanol dehydration device for low-temperature methanol washing. Background Art
[0002] Synthetic ammonia is the main raw material in the fertilizer industry and the basic organic chemical industry. Low-temperature methanol washing is a process in the production of synthetic ammonia. Its principle is to achieve gas purification through the different solubilities of various gases in methanol. The low-temperature methanol washing process can remove impurities such as CO2, H2S, and COS from the shift gas, and at the same time remove the saturated water brought into the shift gas. The low-temperature methanol washing process requires the use of a methanol-water separation tower, whose function is to realize the methanol rectification process by utilizing the different boiling points of methanol and water. Among them, the impurities in methanol are discharged together with the wastewater. However, in the prior art, the production effect of methanol rectification achieved by the methanol-water separation tower is often not high and the stability is poor, resulting in the methanol content in the wastewater being much higher than the calculated value.
[0003] Based on this, a methanol dehydration device for low-temperature methanol washing is now provided, which can eliminate the drawbacks of the existing technical solutions. Summary of the Utility Model
[0004] The purpose of the utility model is to provide a methanol dehydration device for low-temperature methanol washing, so as to solve the problem that the production effect of the methanol-water separation tower in the background art is not high, resulting in the methanol content in the wastewater being much higher than the calculated value.
[0005] To achieve the above purpose, the utility model provides the following technical solutions:
[0006] A methanol dehydration device for low-temperature methanol washing includes a methanol-water separation tower and a carbon dioxide separation tank. The methanol-water separation tower is connected to the carbon dioxide separation tank through a first methanol pipeline. A methanol vapor pipe for discharging methanol is arranged at the top of the methanol-water separation tower. A nitrogen inlet pipe is connected to one side of the methanol-water separation tower close to the reboiler.
[0007] It further includes a reboiler connected to the lower end of the methanol-water separation tower, a first filter arranged on one side of the methanol-water separation tower, a second filter arranged on one side of the methanol-water separation tower, and a heat exchanger connected to the upper end of the methanol-water separation tower.
[0008] Preferably, a carbon dioxide exhaust pipe for discharging H2S and CO2-containing gases is arranged at the top of the carbon dioxide separation tank. The carbon dioxide separation tank is connected to the heat exchanger through a second methanol pipeline.
[0009] Preferably, a steam inlet pipe is provided at the upper end of the reboiler, and a condensate discharge pipe is provided at the lower end of the reboiler, which is used to heat up the liquid and vaporize it again for heat exchange operation.
[0010] Preferably, the input ends of the first filter and the second filter are both connected to the feed pipe, the output ends of the first filter and the second filter are both connected to the heat exchanger through the third methanol pipeline, and valves are provided on one side of the first filter and the second filter.
[0011] Preferably, a dehydrated methanol delivery pipe for inputting dehydrated methanol is provided on one side of the heat exchanger.
[0012] Preferably, the nitrogen flow rate in the nitrogen inlet pipe is about 30 - 80 Nm 3 / h, and the dehydrated methanol flow rate in the dehydrated methanol delivery pipe is 30 - 50 t / h.
[0013] Preferably, the methanol - water separation tower further includes a fixing plate fixedly installed inside it. A motor is provided at the upper end of the fixing plate. The output end of the motor penetrates through the fixing plate and is fixedly connected to a sliding rod. The sliding rod is connected to a rotating shaft through a sliding connection member, and a plurality of stirring rods are evenly distributed on the outer side of the rotating shaft.
[0014] Preferably, the sliding connection member includes a sliding cavity provided at the top of the rotating shaft. The sliding rod is slidably connected to the sliding cavity. The upper end of the rotating shaft is rotatably connected to a connecting plate. The left and right sides of the connecting plate are fixedly connected to the telescopic ends of electric telescopic rods, and the electric telescopic rods are fixedly arranged at the bottom of the fixing plate.
[0015] Compared with the prior art, the beneficial effects of the present utility model are as follows:
[0016] 1. The present utility model adds a nitrogen inlet pipe and a reboiler on one side of the methanol - water separation tower, thereby enhancing the mass transfer and heat transfer effects, improving the methanol rectification effect, saving the steam usage amount at the same time, making the water content in the methanol vapor less than 0.4%, and the methanol content in the methanol wastewater less than 150 PPM, thus solving the problem that the water content in the methanol vapor and the methanol - water content are higher than the design indexes. And because of the addition of the nitrogen inlet pipe, the overall gas volume of the device increases, avoiding fluctuations under low load conditions;
[0017] 2. The present utility model sets a first filter and a second filter on one side of the feed pipe, which can effectively filter out substances such as pulverized coal, kerosene, aromatic hydrocarbons, benzene, and naphthalene in the methanol - water mixture, ensuring the cleanliness of the methanol - water mixture, and avoiding phenomena such as liquid flooding, gas - liquid entrainment, and liquid leakage in the methanol - water separation tower caused by the entry of pulverized coal, kerosene, or organic substances, ensuring the stability of methanol - water separation;
[0018] 3. The present utility model is provided with a heat exchanger and a carbon dioxide separation tank, and performs temperature increase and pressure reduction flash evaporation operations before the methanol and water mixture enters the methanol-water separation tower, thereby analyzing and removing most of the carbon dioxide and hydrogen sulfide substances, effectively reducing the gas components in the methanol-water separation tower, and avoiding phenomena such as flooding, gas-liquid entrainment, and liquid leakage caused by the entry of carbon dioxide, hydrogen sulfide, etc. into the methanol-water separation tower. BRIEF DESCRIPTION OF THE DRAWINGS
[0019] Figure 1 It is a schematic structural diagram of the whole of the present utility model.
[0020] Figure 2 It is a schematic structural diagram of the present utility model.
[0021] Figure 3 For the present utility model Figure 2 An enlarged view of part A.
[0022] Figure 4 It is a schematic structural diagram of Embodiment 2 of the present utility model.
[0023] Annotation of reference numerals: Methanol-water separation tower 10, First methanol pipeline 11, Methanol vapor pipe 12, Nitrogen inlet pipe 13, Fixed plate 14, Slide bar 15, Rotating shaft 16, Stirring rod 17, Slide cavity 18, Electric telescopic rod 19, Carbon dioxide separation tank 20, Carbon dioxide exhaust pipe 21, Second methanol pipeline 22, Reboiler 30, Steam inlet pipe 31, Condensate discharge pipe 32, First filter 40, Second filter 50, Heat exchanger 60, Third methanol pipeline 61, Dehydrated methanol delivery pipe 62, Feed pipe 70, Valve 80. DETAILED DESCRIPTION OF THE EMBODIMENTS
[0024] In order to make the objectives, technical solutions and advantages of the present utility model clearer, the present utility model will be further described in detail below with reference to the accompanying drawings and embodiments.
[0025] Embodiment 1
[0026] In this embodiment, as Figures 1 - 3 shown, a methanol dehydration device for low-temperature methanol washing includes a methanol-water separation tower 10 and a carbon dioxide separation tank 20. The methanol-water separation tower 10 and the carbon dioxide separation tank 20 are connected by a first methanol pipeline 11. A methanol vapor pipe 12 for discharging methanol is provided at the top of the methanol-water separation tower 10. A nitrogen inlet pipe 13 is connected to one side of the methanol-water separation tower 10 close to the reboiler 30. Before the methanol dehydration device for low-temperature methanol washing starts to be used, first check whether the device can be used normally, and then perform opening and closing operations on the valve 70 to make the device enter the standby state;
[0027] It also includes a reboiler 30, which is connected to the lower end of the methanol-water separation tower 10 and is used to heat up the liquid and vaporize it again, a first filter 40, which is arranged on one side of the methanol-water separation tower 10, a second filter 50, which is arranged on one side of the methanol-water separation tower 10 and filters substances such as pulverized coal, kerosene, aromatic hydrocarbons, benzene, and naphthalene in the methanol-water mixture to improve the production quality and efficiency, and a heat exchanger 60, which is connected to the upper end of the methanol-water separation tower 10 and is used for heat exchange operations;
[0028] Among them, as Figures 1 - 3 shown, a carbon dioxide exhaust pipe 21 for discharging H2S- and CO2-containing gases is provided at the top of the carbon dioxide separation tank 20, and the carbon dioxide separation tank 20 is connected to the heat exchanger 60 through a second methanol pipeline 22 to increase the structural stability and enable the corresponding substances to enter the subsequent operations smoothly;
[0029] Among them, as Figure 1 and Figure 2 shown, a steam inlet pipe 31 is provided at the upper end of the reboiler 30, and a condensate discharge pipe 32 is provided at the lower end of the reboiler 30 to facilitate the vaporization operation;
[0030] Among them, as Figure 1 and Figure 2 shown, the input ends of the first filter 40 and the second filter 50 are both connected to the feed pipe 70 to facilitate the injection of the methanol-water mixture. The output ends of the first filter 40 and the second filter 50 are both connected to the heat exchanger 60 through a third methanol pipeline 61, which is convenient for classifying according to the substance content in the methanol-water mixture and selecting a suitable filter to improve the filtration effect. Valves 80 are provided on one side of the first filter 40 and the second filter 50, and the valves 80 play a role in controlling the opening and closing to facilitate ensuring the normal operation of the device;
[0031] Among them, as Figure 1 and Figure 2 shown, a dehydrated methanol delivery pipe 62 for inputting dehydrated methanol is provided on one side of the heat exchanger 60, and control valves are provided on the outer sides of the first methanol pipeline 11 and the second methanol pipeline 22 to facilitate controlling the content and rate;
[0032] Among them, as Figure 1 and Figure 2 shown, the nitrogen flow rate of the nitrogen inlet pipe 13 is about 30 - 80 Nm 3 / h, and the dehydrated methanol flow rate of the dehydrated methanol delivery pipe 62 is 30 - 50 t / h. The flow rate is limited to avoid mistakes caused by too much or too little input;
[0033] Example 2
[0034] Differing from Example 1, as Figure 4 shown, the methanol-water separation tower 10 further includes a fixing plate 14 fixedly installed inside it. At the upper end of the fixing plate 14, there is a motor, which is a common type of motor in the field and has good protection performance to avoid being corroded by substances and greatly reducing its service life. The output end of the motor penetrates through the fixing plate 14 and is fixedly connected to a sliding rod 15. The sliding rod 15 is connected to the rotating shaft 16 through a sliding connection member. A number of stirring rods 17 are evenly distributed on the outer side of the rotating shaft 16. By driving the sliding rod 15, the rotating shaft 16 and the stirring rods 17 to rotate through the motor, the methanol substances inside the methanol-water separation tower 10 can be stirred, so as to prevent the occurrence of temperature difference during the heating process, thereby shortening the heating time, enabling the methanol to be heated evenly, and improving work efficiency;
[0035] As Figure 4 shown, the sliding connection member includes a sliding cavity 18 provided at the top of the rotating shaft 16. The sliding rod 15 is slidably connected to the sliding cavity 18. The upper end of the rotating shaft 16 is rotatably connected to a connecting plate, so as to prevent the telescopic operation of the electric telescopic rod 19 from interfering with the use of the motor. Both the left and right sides of the connecting plate are fixedly connected to the telescopic ends of the electric telescopic rod 19, so as to drive the stirring rods 17 to move up and down, increasing the stirring range and area. The electric telescopic rod 19 is fixedly arranged at the bottom of the fixing plate 14 to ensure the normal use of the device.
[0036] During use, the methanol to be dehydrated is fed into the upper part of the methanol-water separation tower 10 through the dehydrated methanol delivery pipe 62. The methanol-water mixture enters the first filter 40 and the second filter 50 through the feed pipe 70. The substances that have undergone temperature increase and pressure reduction flashing operations enter the methanol-water separation tower 10 through the heat exchanger 60 and the carbon dioxide separation tank 20. The steam injected through the steam inlet pipe 31 provides heat to the bottom of the methanol-water separation tower 10, thereby facilitating the rectification operation. The nitrogen injected through the nitrogen inlet pipe 13 enhances mass transfer and heat transfer and improves the methanol dehydration effect. The structure of this device is relatively simple and has good practicability.
[0037] The above is only the specific implementation manner of this application, but the protection scope of this application is not limited thereto. Any person skilled in the art within the technical scope disclosed in this application can easily think of changes or substitutions, which should all be covered within the protection scope of this application. Therefore, the protection scope of this application should be subject to the protection scope of the claims.
Claims
1. A methanol dehydration device for low-temperature methanol washing, comprising a methanol-water separation tower (10) and a carbon dioxide separation tank (20). The methanol-water separation tower (10) is connected to the carbon dioxide separation tank (20) through a first methanol pipeline (11). A methanol vapor pipe (12) for discharging methanol is provided at the top of the methanol-water separation tower (10). A nitrogen inlet pipe (13) is connected to one side of the methanol-water separation tower (10) close to the reboiler (30). It is characterized in that It further includes a reboiler (30), and the reboiler (30) is connected to the lower end of the methanol-water separation tower (10). A first filter (40), and the first filter (40) is arranged on one side of the methanol-water separation tower (10). A second filter (50), and the second filter (50) is arranged on one side of the methanol-water separation tower (10). A heat exchanger (60), and the heat exchanger (60) is connected to the upper end of the methanol-water separation tower (10).
2. The methanol dehydration device for low-temperature methanol washing according to claim 1, characterized in that A carbon dioxide exhaust pipe (21) for discharging H2S- and CO2-containing gas is provided at the top of the carbon dioxide separation tank (20). The carbon dioxide separation tank (20) is connected to the heat exchanger (60) through a second methanol pipeline (22).
3. The methanol dehydration device for low-temperature methanol washing according to claim 1, characterized in that, A vapor inlet pipe (31) is provided at the upper end of the reboiler (30), and a condensate discharge pipe (32) is provided at the lower end of the reboiler (30).
4. The methanol dehydration device for low-temperature methanol washing according to claim 2, wherein The input ends of the first filter (40) and the second filter (50) are both connected to a feed pipe (70). The output ends of the first filter (40) and the second filter (50) are both connected to the heat exchanger (60) through a third methanol pipeline (61). Valves (80) are arranged on one side of the first filter (40) and the second filter (50).
5. The methanol dehydration device for low-temperature methanol washing according to claim 1, wherein, A dehydrated methanol delivery pipe (62) for inputting methanol to be dehydrated is arranged on one side of the heat exchanger (60).
6. The methanol dehydration device for low-temperature methanol washing according to claim 5, characterized in that, The nitrogen flow rate of the nitrogen inlet pipe (13) is about 30 - 80 Nm 3 / h, and the dehydrated methanol flow rate of the dehydrated methanol delivery pipe (62) is 30 - 50 t / h.
7. The methanol dehydration device for low-temperature methanol washing according to claim 1, characterized in that, The methanol-water separation tower (10) further includes a fixing plate (14) fixedly installed inside it. A motor is provided at the upper end of the fixing plate (14). The output end of the motor penetrates through the fixing plate (14) and is fixedly connected to a sliding rod (15). The sliding rod (15) is connected to a rotating shaft (16) through a sliding connection member. A plurality of stirring rods (17) are evenly distributed on the outer side of the rotating shaft (16).
8. The methanol dehydration device for low-temperature methanol washing according to claim 7, characterized in that, The sliding connection member includes a sliding cavity (18) arranged at the top of the rotating shaft (16). The sliding rod (15) is slidably connected to the sliding cavity (18). The upper end of the rotating shaft (16) is rotatably connected to a connecting plate. Both the left and right sides of the connecting plate are fixedly connected to the telescopic ends of electric telescopic rods (19). The electric telescopic rods (19) are fixedly arranged at the bottom of the fixing plate (14).