CN113135827A - Method for continuously and stably recovering aniline in aniline wastewater - Google Patents
Method for continuously and stably recovering aniline in aniline wastewater Download PDFInfo
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- CN113135827A CN113135827A CN202110473470.XA CN202110473470A CN113135827A CN 113135827 A CN113135827 A CN 113135827A CN 202110473470 A CN202110473470 A CN 202110473470A CN 113135827 A CN113135827 A CN 113135827A
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Abstract
The invention belongs to the technical field of organic chemical raw material preparation, and relates to a method for continuously and stably recovering aniline in aniline wastewater, which is characterized in that an aniline wastewater recovery pipeline is provided with an automatic aniline wastewater flow control device to control the water content of aniline in an aniline crude product entering an aniline refining system, and the aniline crude product enters the aniline refining system to prepare an aniline pure product; the aniline wastewater flow control device comprises a conductivity meter. According to the invention, the aniline in the aniline wastewater is accurately recovered through the conductivity meter, the water content of the aniline in the recovery process is reduced, and the influence on the operation condition of the aniline primary distillation tower due to the mixing of the wastewater is avoided; the recovered aniline and the separated crude aniline enter an aniline primary distillation tower to be refined, so that the water content of the aniline entering the primary distillation tower is less than 2.0%, and the stable operation of an aniline refining system is ensured.
Description
Technical Field
The invention belongs to the technical field of organic chemical raw material preparation, and relates to a method for continuously and stably recovering aniline in aniline wastewater.
Background
Aniline is an important organic chemical raw material and chemical product, and is mainly used for producing MDI, rubber auxiliaries, medicines, dyes, pigments, intermediates and the like.
The reaction product obtained by preparing aniline by gas-phase hydrogenation of nitrobenzene is condensed and separated to obtain aniline wastewater and crude aniline product, and the specific gravity difference between the aniline wastewater and the crude aniline product is small (1.02 kg/m aniline)3(ii) a 1.00kg/m water3) In most cases, aniline wastewater generated by physical separation carries a part of aniline to enter an aniline wastewater storage tank and continuously accumulates at the bottom of the tank, in order to recycle the part of aniline, the aniline needs to be recycled once every 12 hours and directly enters an aniline primary distillation tower for primary distillation operation, but the wastewater in aniline is inevitably carried into the aniline primary distillation tower in the recycling process, so that the operation parameters of the aniline primary distillation tower are severely fluctuated, a large amount of control indexes are subjected to label removal alarm, the continuity and stability of the operation of an aniline refining system are seriously damaged, the low-boiling content of aniline is increased, and the product quality is seriously influenced.
Disclosure of Invention
Aiming at the defects of the prior art, the invention provides a method for continuously and stably recovering aniline in aniline wastewater, thereby ensuring the continuity and stability of the operation of an aniline refining system. Particularly, whether the aniline in the aniline wastewater is completely recovered is judged by reading the conductivity meter in the recovery process, so that the aim of continuously recovering the aniline in the aniline wastewater is fulfilled.
The invention adopts the main technical scheme that: a method for continuously and stably recovering aniline in aniline wastewater is characterized in that an aniline wastewater recovery pipeline is provided with an automatic aniline wastewater flow control device to control the water content of aniline in an aniline crude product entering an aniline refining system, and the aniline crude product enters the aniline refining system to prepare an aniline pure product; the aniline wastewater flow control device comprises a conductivity meter.
Generally, the method for continuously and stably recovering the aniline in the aniline wastewater mainly comprises an aniline wastewater tank, an aniline crude product tank and an aniline refining system, wherein an aniline wastewater flow automatic control device is arranged between the aniline wastewater tank and the aniline crude product tank.
The aniline wastewater flow control device comprises a centrifugal pump, an automatic regulating valve and a flowmeter, wherein a conductivity meter is arranged in a bypass of the automatic regulating valve.
The flow range of the centrifugal pump is 0-10 m3/h。
And controlling the water content of the aniline in the aniline crude product entering the aniline refining system to be less than 2.0%.
And the switch of the automatic regulating valve is controlled by a conductivity meter.
And when the display value of the conductivity meter is more than 0.02s/m, the automatic regulating valve is closed, and the recovery is stopped.
The aniline refining system comprises an aniline primary distillation tower and an aniline rectification tower.
The operating conditions of the preliminary distillation tower are as follows: the temperature of the top of the tower is 100-135 ℃, the temperature of the bottom of the tower is 140-150 ℃, and the pressure of the top of the tower is 20-45 kPa (A); the operating conditions of the rectifying tower are as follows: the temperature at the top of the tower is 100-120 ℃, the temperature at the bottom of the tower is less than or equal to 115 ℃, and the pressure at the top of the tower is less than or equal to 15 kPa (A).
Compared with the prior art, the invention has the beneficial effects that:
(1) the aniline in the aniline wastewater is accurately recovered through a conductivity meter, the water content of the aniline in the recovery process is reduced, and the influence on the operation condition of the aniline primary distillation tower due to the mixing of the wastewater is avoided;
(2) the recovered aniline and the separated crude aniline enter an aniline primary distillation tower to be refined, so that the water content of the aniline entering the primary distillation tower is less than 2.0%, and the stable operation of an aniline refining system is ensured.
Drawings
FIG. 1 is a schematic process flow diagram of an embodiment of the method of the present invention.
In the figure, 1-aniline waste water tank; 2-valve I; 3-a centrifugal pump I; 4-automatic regulating valve; 5-a conductivity meter; 6-a flow meter; 7-aniline crude product tank; 8-valve II; 9-centrifugal pump II; a 10-aniline primary distillation tower; 11-aniline rectifying tower.
Detailed Description
The process of the invention is described in detail below with reference to examples and figures.
Examples
The process of the following example was used in a nitrobenzene vapor phase hydrogenation aniline production scheme.
Referring to the attached figure 1, the process flow mainly comprises an aniline wastewater tank 1, an aniline crude product tank 7 and an aniline refining system, and an aniline wastewater flow automatic control device is arranged between the aniline wastewater tank 1 and the aniline crude product tank 7.
In the embodiment, the aniline wastewater flow control device mainly comprises a centrifugal pump I, an automatic regulating valve 4 and a flowmeter 6, wherein a conductivity meter 5 is arranged on a bypass of the automatic regulating valve 4.
In the embodiment, the flow range of the centrifugal pump I is 0-10 m3H; the water content of 7 aniline in the crude product tank is less than 2.0 percent; the switch of the automatic regulating valve 4 is controlled by the conductivity meter 5, when the display value of the conductivity meter 5 is more than 0.02s/m, the automatic regulating valve 4 is closed, and the recovery is stopped.
In an embodiment, the aniline refining system comprises an aniline primary distillation tower and an aniline rectification tower.
Operating conditions of the preliminary distillation tower: the temperature of the top of the tower is 100-135 ℃, the temperature of the bottom of the tower is 140-150 ℃, and the pressure of the top of the tower is 20-45 kPa (A); the operating conditions of the rectifying tower are as follows: the temperature at the top of the tower is 100-120 ℃, the temperature at the bottom of the tower is less than or equal to 115 ℃, and the pressure at the top of the tower is less than or equal to 15 kPa (A).
Example 1
And (3) a discharge valve I at the lower part of the aniline wastewater tank is opened, a centrifugal pump I is started, an outlet valve II of the centrifugal pump is opened, crude aniline is recycled into the aniline crude product tank, when the conductivity meter shows that the concentration is 0.020s/m, the recycling is stopped, and the water content in the aniline crude product tank is analyzed to be 1.81%.
Example 2
And (3) a discharge valve I at the lower part of the aniline wastewater tank is opened, a centrifugal pump I is started, an outlet valve II of the centrifugal pump is opened, crude aniline is recovered into the aniline crude product tank, when a conductivity meter shows that the concentration is 0.012s/m, the recovery is stopped, and the water content in the aniline crude product tank is analyzed to be 0.98%.
Example 3
And (3) a discharge valve I at the lower part of the aniline wastewater tank is opened, a centrifugal pump I is started, an outlet valve II of the centrifugal pump is opened, crude aniline is recovered into the aniline crude product tank, when a conductivity meter shows that the concentration is 0.008s/m, the recovery is stopped, and the water content in the aniline crude product tank is analyzed to be 0.76%.
Example 4
And (3) a discharge valve I at the lower part of the aniline wastewater tank is opened, a centrifugal pump I is started, an outlet valve II of the centrifugal pump is opened, crude aniline is recovered into the aniline crude product tank, when a conductivity meter shows that the concentration is 0.000s/m, the recovery is stopped, and the water content in the aniline crude product tank is analyzed to be 0.58%.
Comparative example 1
And (3) a discharge valve I at the lower part of the aniline wastewater tank is opened, a centrifugal pump I is started, an outlet valve II of the centrifugal pump is opened, crude aniline is recovered into the aniline crude product tank, when a conductivity meter shows that the concentration is 0.230s/m, the recovery is stopped, and the water content in the aniline crude product tank is analyzed to be 3.58%.
Comparative example 2
And (3) a discharge valve I at the lower part of the aniline wastewater tank is opened, a centrifugal pump I is started, an outlet valve II of the centrifugal pump is opened, feeding is carried out on the aniline primary distillation tower, and the water content in the aniline crude product tank is analyzed to be 5.36%.
The effect is shown in the following table:
| serial number | temperature/deg.C of top of primary tower | First distillation tower top pressure/kPa (A) | Low boiler content/% of aniline |
| Example 1 | 105.0~120.6 | 24~32 | 0.003240 |
| Example 2 | 106.3~118.6 | 26~31 | 0.003150 |
| Example 3 | 107.0~117.4 | 27~30 | 0.003010 |
| Example 4 | 107.5~114.0 | 28~29 | 0.002840 |
| Comparative example 1 | 95.8~130.9 | 32~53 | 0.005370 |
| Comparative example 2 | 94.4~133.4 | 30~58 | 0.006390 |
The changes of the temperature and the pressure at the top of the aniline primary distillation tower and the content of the low-boiling-point substances in the aniline show that the lower the water content in the crude aniline, the more stable the crude distillation system and the lower the content of the low-boiling-point substances in the refined aniline; the water content of the recovered aniline can be well controlled by the conductivity meter, and the aim of continuously, stably and effectively recovering the aniline is fulfilled.
Claims (9)
1. A method for continuously and stably recovering aniline in aniline wastewater is characterized in that an aniline wastewater recovery pipeline is provided with an automatic aniline wastewater flow control device to control the water content of aniline in an aniline crude product entering an aniline refining system, and the aniline crude product enters the aniline refining system to prepare an aniline pure product; the aniline wastewater flow control device comprises a conductivity meter.
2. The method for continuously and stably recovering the aniline in the aniline waste water according to claim 1, which comprises an aniline waste water tank, an aniline crude product tank and an aniline refining system, wherein an aniline waste water flow automatic control device is arranged between the aniline waste water tank and the aniline crude product tank.
3. The method for continuously and stably recovering the aniline in the aniline waste water according to claim 1 or 2, wherein the aniline waste water flow control device comprises a centrifugal pump, an automatic regulating valve and a flow meter, and the automatic regulating valve is provided with a conductivity meter in a bypass.
4. The method for continuously and stably recovering the aniline from the aniline wastewater according to claim 3, wherein the flow rate of the centrifugal pump is in the range of 0-10 m3/h。
5. The method for continuously and stably recovering the aniline from the aniline wastewater according to claim 1, wherein the water content of the aniline in the aniline crude product entering the aniline refining system is controlled to be less than 2.0%.
6. The method for continuously and stably recovering the aniline from the aniline waste water according to claim 3, wherein the opening and closing of the automatic regulating valve is controlled by a conductivity meter.
7. The method for continuously and stably recovering aniline from aniline waste water according to claim 3, wherein the automatic regulating valve is closed when the conductivity meter shows a value of more than 0.02 s/m.
8. The method for continuously and stably recovering the aniline from the aniline wastewater according to claim 1, wherein the aniline refining system comprises an aniline primary distillation tower and an aniline rectification tower.
9. The method for continuously and stably recovering the aniline from the aniline wastewater according to claim 8, wherein the operating conditions of the preliminary distillation tower are as follows: the temperature of the top of the tower is 100-135 ℃, the temperature of the bottom of the tower is 140-150 ℃, and the pressure of the top of the tower is 20-45 kPa (A); the operating conditions of the rectifying tower are as follows: the temperature at the top of the tower is 100-120 ℃, the temperature at the bottom of the tower is less than or equal to 115 ℃, and the pressure at the top of the tower is less than or equal to 15 kPa (A).
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Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1600696A (en) * | 2004-10-12 | 2005-03-30 | 南化集团研究院 | Nitrobenzene extraction method for treating aniline wastewater |
| CN102249376A (en) * | 2011-05-20 | 2011-11-23 | 北京化工大学 | Method for realizing recycling of aniline waste water and zero release through electropolymerization |
| CN102304017A (en) * | 2011-07-20 | 2012-01-04 | 济南圣泉集团股份有限公司 | Method for recycling aniline and methanol from mixed waste water of aniline and methanol |
| CN103641205A (en) * | 2013-10-29 | 2014-03-19 | 南京工业大学 | Dielectric barrier discharge-Fenton treatment combined technology for treating aniline wastewater |
| CN104610070A (en) * | 2015-02-11 | 2015-05-13 | 北海和思科技有限公司 | Combined method for performing dynamic adsorption and rectification on aniline in recycled wastewater |
| CN105906114A (en) * | 2016-07-05 | 2016-08-31 | 中国科学技术大学 | Bipolar membrane electrodialysis system for treating saliferous organic amine waste water by using carbon dioxide and process thereof |
-
2021
- 2021-04-29 CN CN202110473470.XA patent/CN113135827B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1600696A (en) * | 2004-10-12 | 2005-03-30 | 南化集团研究院 | Nitrobenzene extraction method for treating aniline wastewater |
| CN102249376A (en) * | 2011-05-20 | 2011-11-23 | 北京化工大学 | Method for realizing recycling of aniline waste water and zero release through electropolymerization |
| CN102304017A (en) * | 2011-07-20 | 2012-01-04 | 济南圣泉集团股份有限公司 | Method for recycling aniline and methanol from mixed waste water of aniline and methanol |
| CN103641205A (en) * | 2013-10-29 | 2014-03-19 | 南京工业大学 | Dielectric barrier discharge-Fenton treatment combined technology for treating aniline wastewater |
| CN104610070A (en) * | 2015-02-11 | 2015-05-13 | 北海和思科技有限公司 | Combined method for performing dynamic adsorption and rectification on aniline in recycled wastewater |
| CN105906114A (en) * | 2016-07-05 | 2016-08-31 | 中国科学技术大学 | Bipolar membrane electrodialysis system for treating saliferous organic amine waste water by using carbon dioxide and process thereof |
Non-Patent Citations (1)
| Title |
|---|
| 殷宝剑等: "响应曲面法优化介质阻挡放电工艺处理苯胺废水", 《净水技术》 * |
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