Urotropine exhaust gas ammonia formaldehyde vapor condensation recovery device

Abstract

The utility model belongs to tail gas treatment technical field, concretely relates to urotropin tail gas ammonia formaldehyde steam condensation recovery device, including condensing tower and absorption tower, the condensing tower is equipped with first air inlet, first liquid outlet and first gas outlet, the inside of condensing tower is equipped with condensing coil, the top of condensing tower is equipped with first sprinkler pipe, first sprinkler pipe is located above first gas outlet, and the bottom of first sprinkler pipe is equipped with first sprinkler head, absorption tower is equipped with second air inlet, second liquid outlet and second gas outlet, and second air inlet is connected with first gas outlet through gas guide pipe, the inside of absorption tower is equipped with a plurality of porous plate, all be provided with packing layer on every porous plate, the top of every packing layer is provided with second sprinkler pipe respectively, and the bottom of second sprinkler pipe is equipped with second sprinkler head. The device can filter out formaldehyde and ammonia in tail gas, and can recover formaldehyde and ammonia, reduce resource waste, and reduce environmental pollution.

Description

Technical Field

[0001] This utility model belongs to the field of exhaust gas treatment technology, specifically relating to a device for condensing and recovering ammonia-formaldehyde vapor from urotropine exhaust gas. Background Technology

[0002] Urotropin, also known as hexamethylenetetramine, has the molecular formula C6H. 12 Hexamethylenetetramine (N4) is an organic compound, a white to pale yellow crystalline powder at room temperature. It is flammable, almost odorless, and has a sweet and bitter taste. It is readily soluble in organic solvents such as water, ethanol, and chloroform, sparingly soluble in benzene and carbon tetrachloride, and insoluble in ether and gasoline. Hexamethylenetetramine is widely used in the resin, plastics, and rubber industries. In medicine, it is used as a diuretic; in the food industry, as a disinfectant; and in agriculture, as a raw material for pesticides.

[0003] The main raw materials for hexamethylenetetramine production are formaldehyde and ammonia. There are two production processes: liquid-phase and gas-phase. The liquid-phase method involves reacting a 37% formaldehyde aqueous solution with ammonia gas to produce a hexamethylenetetramine solution. This solution is then further dehydrated through evaporation, and finally centrifuged and dried to obtain the finished product. Its advantages are: mature technology, simple operation, and a long crystallization time, resulting in large product particles. The gas-phase method involves directly passing formaldehyde gas, generated from methanol conversion, into an ammoniation reactor to react with ammonia gas in a saturated hexamethylenetetramine mother liquor to produce hexamethylenetetramine. Its advantages are: significant steam savings and high product purity.

[0004] In the process of producing hexamethylenetetramine using the gas-phase method, the exhaust gas contains unreacted formaldehyde and ammonia, as well as water vapor and other components. If these exhaust gases are directly emitted, it will not only waste resources but also cause serious environmental pollution.

[0005] Therefore, there is an urgent need for a device for condensing and recovering ammonia-formaldehyde vapor from urotropine tail gas. Utility Model Content

[0006] To address the aforementioned deficiencies in the existing technology, the present invention provides a hexamethylenetetramine tail gas ammonia-formaldehyde vapor condensation and recovery device, comprising a condensation tower and an absorption tower. A first air inlet is provided at the lower part of one side of the condensation tower, a first liquid outlet is provided at the bottom of the condensation tower, and a first air outlet is provided at the upper part of the other side of the condensation tower. A condensation coil is provided inside the condensation tower, and a first spray pipe is provided at the top of the condensation tower. The first spray pipe is located above the first air outlet, and multiple first spray heads are provided at the bottom of the first spray pipe.

[0007] A second air inlet is provided at the lower part of one side of the absorption tower, and the second air inlet is connected to the first air outlet through a gas guide pipe. A second liquid outlet is provided at the bottom of the absorption tower, and a second air outlet is provided at the top of the absorption tower. Several perforated plates are arranged inside the absorption tower from top to bottom. Each perforated plate is provided with a packing layer. A second spray pipe is provided above each packing layer, and multiple second spray heads are provided at the bottom of the second spray pipe.

[0008] Optionally, the condenser coil is located between the first air inlet and the first air outlet, and the condenser coil is provided with a coolant inlet and a coolant outlet, both of which extend out of the condenser tower.

[0009] Optionally, the first outlet of the condenser is connected to a recovery tank via a first connecting pipe, and the first connecting pipe is equipped with a first electric valve and a first delivery pump.

[0010] Optionally, a first filter plate is provided at the bottom of the condenser tower, and the first filter plate is located below the first air inlet.

[0011] Optionally, a first induced draft fan and a manual ball valve are installed on the air duct.

[0012] Optionally, the second outlet of the absorption tower is connected to a circulation tank via a second connecting pipe, and a second electric valve and a second delivery pump are installed on the second connecting pipe. The circulation tank is connected to the second spray pipe via a delivery pipe, and a third electric valve and a circulation pump are installed on the delivery pipe.

[0013] Optionally, a second filter plate is provided at the bottom of the absorption tower, and the second filter plate is located below the second air inlet.

[0014] Optionally, the second outlet of the absorption tower is connected to an exhaust pipe, and the exhaust pipe is equipped with a filter and a second induced draft fan.

[0015] Optionally, the filter includes a housing and a cover plate detachably connected to the bottom of the housing. The top surface of the cover plate is provided with a first annular groove and a second annular groove arranged in concentric circles, with the first annular groove located inside the second annular groove. The bottom of the cover plate is connected to a filter inlet, which is located inside the first annular groove. The top of the housing is connected to a filter outlet. The inside of the housing is provided with a first filter screen and a second filter screen, with the first filter screen located inside the second filter screen. The bottom of the first filter screen is threadedly connected to the first annular groove, and the bottom of the second filter screen is threadedly connected to the second annular groove. An activated carbon adsorption layer is filled between the first filter screen and the second filter screen, and an acidic adsorbent is filled between the second filter screen and the inner wall of the housing.

[0016] Specifically, the activated carbon adsorption layer in the filter is used to adsorb residual organic matter such as formaldehyde in the exhaust gas, and the acidic adsorbent can be used to absorb residual ammonia in the exhaust gas; the first filter screen and the second filter screen not only play a filtering role, but also separate the activated carbon adsorption layer and the acidic adsorbent, playing a certain limiting role. At the same time, the first filter screen and the second filter screen are connected to the cover plate by a detachable connection structure, which is convenient for disassembly and replacement.

[0017] This invention also includes other components that enable the urotropine tail gas ammonia-formaldehyde vapor condensation and recovery device to operate normally, all of which are conventional technologies in the field. Furthermore, any devices or components not specified in this invention employ conventional technologies in the field, such as the first induced draft fan and the second induced draft fan.

[0018] The working principle of this invention is as follows: exhaust gas is introduced into the condensing tower through the first inlet. Under the guidance of the first induced draft fan, it flows upward through the condensing coil. Coolant flows in the condensing coil and exchanges heat with the exhaust gas. The coolant is then discharged from the condensing coil, while the ammonia and formaldehyde in the exhaust gas are condensed and liquefied. Simultaneously, the first spray pipe at the top of the condensing tower is opened, spraying absorbent liquid downwards to adsorb and filter out most of the ammonia and formaldehyde in the exhaust gas. The liquid ammonia and formaldehyde are then filtered through the first filter plate and flow into a recovery tank for storage. Afterwards, the exhaust gas enters the absorption tower through the gas guide pipe. Under the guidance of the second induced draft fan, it passes upward through layers of packing and the second spray pipe. At this time, the second spray pipe is opened to spray out the absorption liquid, which adsorbs and filters out the remaining ammonia and formaldehyde in the exhaust gas. The liquid ammonia and formaldehyde are filtered by the second filter plate and flow into the circulation tank. Then, under the action of the circulation pump, the absorption liquid is recycled to improve the adsorption effect. Finally, the exhaust gas after condensation and recovery treatment is discharged from the second outlet and discharged to the next process after being purified and filtered by the filter.

[0019] The beneficial effects of this invention are that, through the condensation tower and absorption tower, formaldehyde and ammonia in the exhaust gas can be adsorbed and filtered out, and formaldehyde and ammonia can be recovered, reducing resource waste; through the filter, residual formaldehyde and ammonia in the exhaust gas can be purified and filtered out, improving the purification effect and reducing environmental pollution. Attached Figure Description

[0020] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0021] Figure 1 This is a schematic diagram of the overall structure of this utility model.

[0022] Figure 2 This is a schematic diagram of the structure of the filter of this utility model.

[0023] In the diagram: 1. Condensation tower, 2. Absorption tower, 3. First air inlet, 4. First liquid outlet, 5. Recovery tank, 6. First air outlet, 7. Condensation coil, 8. First spray pipe, 9. First filter plate, 10. Second air inlet, 11. Air guide pipe, 12. First induced draft fan, 13. Perforated plate, 14. Packing layer, 15. Second spray pipe, 16. Second liquid outlet, 17. Circulation tank, 18. Second air outlet, 19. Filter, 20. Second induced draft fan, 21. Shell, 22. Cover plate, 23. First annular groove, 24. Second annular groove, 25. Filter inlet, 26. Filter outlet, 27. First filter screen, 28. Second filter screen, 29. Activated carbon adsorption layer, 30. Acidic adsorbent, 31. Second filter plate. Detailed Implementation

[0024] The present invention will now be clearly described with reference to the accompanying drawings and specific embodiments. This description is merely for explaining the present invention and is not intended to limit it. Any modifications, equivalent substitutions, improvements, etc., made by those skilled in the art based on the embodiments of the present invention without inventive effort to obtain all other embodiments should be included within the protection scope of the present invention.

[0025] Example

[0026] like Figure 1-2 As shown in the figure, the urotropine tail gas ammonia-formaldehyde vapor condensation and recovery device provided in this embodiment of the present invention includes a condensation tower 1 and an absorption tower 2. A first air inlet 3 is provided at the lower part of one side of the condensation tower 1, and a first liquid outlet 4 is provided at the bottom of the condensation tower 1. The first liquid outlet 4 is connected to a recovery tank 5 through a first connecting pipe, and a first electric valve and a first liquid pump are provided on the first connecting pipe. A first air outlet 6 is provided at the upper part of the other side of the condensation tower 1. A condensation coil 7 is provided inside the condensation tower 1. The condensation coil 7 is located between the first air inlet 3 and the first air outlet 6. The condensation coil 7 is provided with a coolant inlet and a coolant outlet, and both the coolant inlet and the coolant outlet extend out of the condensation tower 1. A first spray pipe 8 is provided at the top of the condensation tower 1. The first spray pipe 8 is located above the first air outlet 6, and multiple first spray heads are provided at the bottom of the first spray pipe 8.

[0027] In addition, a first filter plate 9 is provided at the bottom of the condenser tower 1, and the first filter plate 9 is located below the first air inlet 3.

[0028] A second air inlet 10 is provided at the lower part of one side of the absorption tower 2. The second air inlet 10 is connected to the first air outlet 6 through an air guide pipe 11, and a first induced draft fan 12 and a manual ball valve are provided on the air guide pipe 11. Inside the absorption tower 2, several perforated plates 13 are arranged from top to bottom. Each perforated plate 13 is provided with a packing layer 14. A second spray pipe 15 is provided above each packing layer 14, and multiple second spray heads are provided at the bottom of the second spray pipe 15. A second liquid outlet 16 is provided at the bottom of the absorption tower 2, and the second liquid outlet 16 is connected to a circulating water system through a second connecting pipe. The circulating tank 17 is connected to the second spray pipe 15 via a second connecting pipe, and a third electric valve and a circulating pump are installed on the second connecting pipe. The top of the absorption tower 2 has a second air outlet 18 connected to an exhaust pipe, which is equipped with a filter 19 and a second induced draft fan 20. The filter 19 includes a housing 21 and a cover plate 22 detachably connected to the bottom of the housing 21. The top surface of the cover plate 22 has a first annular groove 23 and a second annular groove 24 arranged concentrically. 23 is located inside the second annular groove 24. The bottom of the cover plate 22 is connected to a filter inlet 25, which is located inside the first annular groove 23. The top of the housing 21 is connected to a filter outlet 26. The housing 21 is equipped with a first filter screen 27 and a second filter screen 28, with the first filter screen 27 located inside the second filter screen 28. The bottom of the first filter screen 27 is threaded to the first annular groove 23, and the bottom of the second filter screen 28 is threaded to the second annular groove 24. An activated carbon adsorption layer 2 is filled between the first filter screen 27 and the second filter screen 28. 9. The space between the second filter screen 28 and the inner wall of the housing 21 is filled with an acidic adsorbent 30. The activated carbon adsorption layer 29 in the filter 19 is used to adsorb residual organic matter such as formaldehyde in the exhaust gas, and the acidic adsorbent 30 can be used to absorb residual ammonia in the exhaust gas. The first filter screen 27 and the second filter screen 28 not only play a filtering role, but also separate the activated carbon adsorption layer 29 and the acidic adsorbent 30, which plays a certain limiting role. At the same time, the first filter screen 27 and the second filter screen 28 are connected to the cover plate 22 by a detachable connection structure, which is convenient for disassembly and replacement.

[0029] In addition, a second filter plate 31 is provided at the bottom of the absorption tower 2, and the second filter plate 31 is located below the second air inlet 10.

[0030] The working principle of this utility model is as follows: exhaust gas is introduced into the condenser tower 1 through the first air inlet 3. Under the induced flow of the first induced draft fan 12, it passes upward through the condenser coil 7. Coolant flows in the condenser coil 7. After heat exchange with the exhaust gas, the coolant is discharged from the condenser coil 7, while the ammonia and formaldehyde in the exhaust gas are condensed and liquefied. At the same time, the first spray pipe 8 at the top of the condenser tower 1 is opened, and absorbent liquid is sprayed downward to adsorb and filter out most of the ammonia and formaldehyde in the exhaust gas. The liquid ammonia and formaldehyde are filtered through the first filter plate 9 and then flow into the recovery tank 5 for storage. After that, the exhaust gas is discharged into the condenser coil 7. The gas enters the absorption tower 2 through the gas guide pipe 11. Under the guidance of the second induced draft fan 20, it passes upward through the layers of packing 14 and the second spray pipe 15. At this time, the second spray pipe 15 is opened to spray out the absorption liquid, which adsorbs and filters out the remaining ammonia and formaldehyde in the tail gas. The ammonia and formaldehyde, after being filtered by the second filter plate 31, flow into the circulation tank 17. Then, under the action of the circulation pump, the absorption liquid is recycled to improve the adsorption effect. Finally, the tail gas after condensation and recovery treatment is discharged from the second outlet 18 and discharged to the next process after being purified and filtered by the filter 19.

[0031] The embodiments of the present invention have been described above. These descriptions are exemplary and not exhaustive, nor are they limited to the disclosed embodiments. Many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments.

Claims

1. A condensation and recovery device for hexamethylenetetramine tail gas ammonia-formaldehyde vapor, comprising a condensation tower and an absorption tower, characterized in that: A first air inlet is provided at the lower part of one side of the condensing tower, a first liquid outlet is provided at the bottom of the condensing tower, a first air outlet is provided at the upper part of the other side of the condensing tower, a condensing coil is provided inside the condensing tower, a first spray pipe is provided at the top of the condensing tower, the first spray pipe is located above the first air outlet, and multiple first spray heads are provided at the bottom of the first spray pipe. A second air inlet is provided at the lower part of one side of the absorption tower, and the second air inlet is connected to the first air outlet through a gas guide pipe. A second liquid outlet is provided at the bottom of the absorption tower, and a second air outlet is provided at the top of the absorption tower. Several perforated plates are arranged inside the absorption tower from top to bottom. Each perforated plate is provided with a packing layer. A second spray pipe is provided above each packing layer, and multiple second spray heads are provided at the bottom of the second spray pipe.

2. The hexamethylenetetramine tail gas ammonia-formaldehyde vapor condensation and recovery device according to claim 1, characterized in that: The condenser coil is located between the first air inlet and the first air outlet, and the condenser coil is equipped with a coolant inlet and a coolant outlet.

3. The urotropine tail gas ammonia-formaldehyde vapor condensation and recovery device according to claim 2, characterized in that: The first liquid outlet of the condenser is connected to a recovery tank via a first connecting pipe.

4. The hexamethylenetetramine tail gas ammonia-formaldehyde vapor condensation and recovery device according to claim 3, characterized in that: The bottom of the condenser tower is equipped with a first filter plate, which is located below the first air inlet.

5. The hexamethylenetetramine tail gas ammonia-formaldehyde vapor condensation and recovery device according to claim 4, characterized in that: The air duct is equipped with a first induced draft fan and a manual ball valve.

6. The urotropine tail gas ammonia-formaldehyde vapor condensation and recovery device according to claim 5, characterized in that: The second outlet of the absorption tower is connected to a circulation tank via a second connecting pipe, and the circulation tank is connected to the second spray pipe via a delivery pipe.

7. The hexamethylenetetramine tail gas ammonia-formaldehyde vapor condensation and recovery device according to claim 6, characterized in that: A second filter plate is installed at the bottom of the absorption tower, and the second filter plate is located below the second air inlet.

8. The urotropine tail gas ammonia-formaldehyde vapor condensation and recovery device according to claim 7, characterized in that: The second outlet of the absorption tower is connected to an exhaust pipe, and the exhaust pipe is equipped with a filter and a second induced draft fan.

9. The urotropine tail gas ammonia-formaldehyde vapor condensation and recovery device according to claim 8, characterized in that: The filter includes a housing and a cover plate connected to the bottom of the housing. The top surface of the cover plate is provided with a first annular groove and a second annular groove, with the first annular groove located inside the second annular groove. The bottom of the cover plate is connected to a filter inlet, which is also located inside the first annular groove. The top of the housing is connected to a filter outlet. The interior of the housing is provided with a first filter screen and a second filter screen, with the first filter screen located inside the second filter screen. The bottom of the first filter screen is threaded to the first annular groove, and the bottom of the second filter screen is threaded to the second annular groove. An activated carbon adsorption layer is filled between the first filter screen and the second filter screen, and an acidic adsorbent is filled between the second filter screen and the inner wall of the housing.

Images