A multi-stage treatment device for dichlorosan production tail gas

Abstract

This utility model discloses a multi-stage treatment device for dichlorosan production tail gas, including a catalytic reaction tank, a water spray tower, an alkali spray tower, and an adsorption tower. The adsorption tower is connected to an exhaust pipe and a chimney. The catalytic reaction tank is equipped with a catalyst addition port and an oxidant addition port. Gas distributors are installed at the bottom of both the water spray tower and the alkali spray tower. Spraying mechanisms are installed at the top of both the water spray tower and the alkali spray tower. The bottom of the alkali spray tower is connected to a pH adjustment tank and a filter. The filter is connected to the spraying mechanism at the top of the alkali spray tower via a reflux pump and a reflux pipe. The spraying mechanism includes multiple layers of spray pipes with multiple nozzles, each layer having a different nozzle inclination angle. The inner wall of the adsorption tower is staggered with downward-sloping corrugated plates, the surface of which has guide grooves. Activated carbon adsorption layers and resin adsorption layers are alternately arranged inside the adsorption tower. This device can effectively remove polluting gases from dichlorosan production tail gas, with high treatment efficiency and no secondary pollution.

Description

Technical Field

[0001] This utility model relates to the field of dichlorosan production technology, specifically to a multi-stage treatment device for dichlorosan production tail gas. Background Technology

[0002] Diclosan, chemically known as 4,4-dichloro-2-hydroxydiphenyl ether, is a highly effective broad-spectrum antibacterial agent widely used in detergents, fabric softeners, cleaning agents, and medical products. Its production primarily involves etherification, diazotization, and hydrolysis reactions. Raw materials include chlorinated organic compounds such as p-chlorophenol and 2,5-dichloronitrobenzene. The reaction process releases a certain amount of chlorinated volatile organic compounds, hydrogen chloride, sulfur dioxide, and unreacted raw material gases. These exhaust gases are complex in composition and highly toxic; direct emission would severely pollute the environment and endanger health.

[0003] Currently, the main methods for treating the aforementioned exhaust gases include: 1. Using a single spray tower; however, traditional spray towers have simple structures and uneven gas distribution, resulting in insufficient gas-liquid contact and low exhaust gas treatment efficiency; 2. Adsorption; however, traditional packed beds are prone to "short-circuiting" due to uneven airflow distribution, leading to localized saturation and failure of the adsorbent. To address these issues, it is necessary to provide a multi-stage treatment device for treating dichlorosan exhaust gases. Utility Model Content

[0004] The technical problem to be solved by this utility model is to provide a multi-stage treatment device for dichlorosan production tail gas, which can effectively remove polluting gases from dichlorosan production tail gas, with high treatment efficiency and no secondary pollution, in order to address the shortcomings of the existing technology.

[0005] To solve the above-mentioned technical problems, the technical solution of this utility model is as follows:

[0006] A multi-stage treatment device for tail gas from dichlorosan production includes a catalytic reaction tank, a water spray tower, an alkali spray tower, and an adsorption tower connected in series. The outlet of the adsorption tower is connected in sequence to an exhaust pipe and an exhaust chimney.

[0007] The catalytic reaction vessel is equipped with multiple layers of catalyst packing.

[0008] Both the water spray tower and the alkali spray tower are equipped with gas distributors at their lower parts; both the water spray tower and the alkali spray tower are equipped with spraying mechanisms at their upper parts. The bottom of the alkali spray tower is connected in sequence to a pH adjustment tank and a filter. The outlet of the filter is connected to the spraying mechanism at the top of the alkali spray tower through a reflux pump and a reflux pipe. The spraying mechanism includes multiple layers of spray pipes, each with multiple nozzles, and the nozzles on each layer of spray pipes have a different inclination angle.

[0009] The inner walls of the water spray tower and the alkali spray tower are provided with downward-sloping corrugated plates, and the surface of the corrugated plates is provided with multiple flow guide holes.

[0010] The adsorption tower is alternately equipped with activated carbon adsorption layers and resin adsorption layers.

[0011] Preferably, the lower part of the catalyst reaction tank is provided with a gas distribution mechanism, which includes a gas distribution plate connected to the gas inlet pipe and a plurality of main gas outlet holes disposed on the gas distribution plate.

[0012] Preferably, the air distribution plate has an air outlet pipe connected to its side wall, the end of the air outlet pipe is closed, and the side wall of the air outlet pipe is provided with multiple auxiliary air outlet holes.

[0013] Preferably, both the main air outlet and the auxiliary air outlet are provided with multiple turbulence fins in the inner circumferential direction.

[0014] Preferably, the gas inlet of the catalytic reaction vessel is connected to a preheater, and the preheater is provided with hollow spiral blades and multiple parallel gas delivery pipes that penetrate the hollow spiral blades. The hollow spiral blades and the jacket of the preheater are both connected to heat exchange medium pipes.

[0015] Preferably, the inner wall of the gas delivery pipe is provided with guide vanes.

[0016] Preferably, the water spray tower and the alkali spray tower are equipped with wire mesh demisters at their air outlets.

[0017] Preferably, a porous partition plate is provided between the activated carbon adsorption layer and the resin adsorption layer.

[0018] Preferably, the exhaust pipe is connected to the air inlet of the catalytic reactor and the exhaust chimney through a gas circulation pipe and a gas discharge pipe, respectively; a first electric valve and a second electric valve are respectively provided on the gas circulation pipe and the gas discharge pipe, and a VOCs detector is provided on the exhaust pipe, and the VOCs detector is interlocked with the first electric valve and the second electric valve, respectively.

[0019] By adopting the above technical solution, this utility model has at least the following beneficial effects:

[0020] 1. This utility model provides a multi-stage treatment device for dichlorosan production tail gas. The device removes various pollutants such as organic matter, acidic gases, and particulate matter in the tail gas in a step-by-step and targeted manner through multi-stage treatment of catalytic oxidation, water washing, alkali washing, and adsorption, with high efficiency.

[0021] 2. The catalytic reaction tank of this device is equipped with a gas distribution mechanism to ensure that the catalyst packing is in full contact with the tail gas, and that the reaction is fully carried out under the action of oxidizing gas, thus preventing reaction dead zones and improving reaction efficiency.

[0022] 3. The gas inlet of the catalytic reaction tank of this device is connected to the preheater. The preheater is equipped with hollow spiral blades and multiple gas delivery pipes. The gas delivery pipes are equipped with guide vanes. The above configuration improves the heat exchange efficiency and reduces energy consumption.

[0023] 4. The water spray tower of this device can remove particulate matter, soluble gases and some organic matter from the exhaust gas, while the alkali spray tower can efficiently remove acidic gases. The gas distributor ensures uniform airflow distribution, and the multi-angle setting of the nozzles can form a dense, cross-covering liquid curtain in the tower, which greatly increases the gas-liquid contact area and contact time, and improves absorption efficiency.

[0024] 5. The bottom of the alkali spray tower is connected to a pH adjustment tank and a filter to achieve the recycling of alkali solution. The pH adjustment tank can be automatically or manually replenished with fresh alkali solution to maintain the optimal absorption pH value; the filter effectively removes solid impurities from the circulating alkali solution, preventing nozzle clogging and system scaling, ensuring continuous and stable spraying effect, and reducing maintenance frequency and operating costs.

[0025] 6. The adsorption tower of this device alternates between activated carbon adsorption layers and resin adsorption layers. The activated carbon adsorption layer mainly adsorbs residual organic matter in the exhaust gas, while the resin adsorption layer can supplement the adsorption of specific polar or large molecular organic matter. The alternating arrangement of the two forms a complementary effect, thereby improving the exhaust gas treatment efficiency. The staggered inclined corrugated plates and guide channels in the adsorption tower can extend the gas path, increase turbulence, and ensure full contact between the gas and the adsorption layer, thereby improving the adsorption efficiency; while the porous partition plate can further ensure uniform gas distribution.

[0026] 7. The VOCs detector on the exhaust pipe of this device is interlocked with the first electric valve and the second electric valve respectively. When the VOCs concentration in the exhaust gas treated in the adsorption tower meets the standard, the second electric valve is opened and the exhaust gas is discharged through the exhaust chimney under the action of the first fan. If the detection exceeds the standard, the first electric valve is automatically switched to open and the unqualified exhaust gas is sent back to the inlet of the catalytic reaction tank for secondary treatment, ensuring that the final emission meets the standard. Attached Figure Description

[0027] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0028] Figure 1 This is a schematic diagram of the structure of Embodiment 1 of this utility model;

[0029] Figure 2 This is a schematic diagram of the internal structure of the preheater;

[0030] Figure 3 This is a schematic diagram of the internal structure of a gas delivery pipe;

[0031] Figure 4 This is a schematic diagram of the air distribution plate.

[0032] Figure 5 yes Figure 4 Enlarged structural diagram at point A;

[0033] Figure 6 This is a structural diagram of a corrugated plate;

[0034] In the diagram, 1. Catalytic reaction tank; 2. Water spray tower; 3. Alkali spray tower; 4. Adsorption tower; 5. Exhaust pipe; 6. Gas circulation pipe; 7. Gas emission pipe; 8. Exhaust chimney; 9. First electric valve; 10. Second electric valve; 11. VOCs detector; 12. Catalyst packing layer; 13. Inlet pipe; 14. Gas distribution plate; 15. Main outlet; 16. Outlet pipe; 17. Auxiliary outlet; 18. Turbulence fins. 19. Preheater; 20. Hollow spiral blades; 21. Gas delivery pipe; 22. Heat exchange medium pipe; 23. Gas distributor; 24. pH adjustment tank; 25. Filter; 26. Return pump; 27. Return pipe; 28. Spray pipe; 29. ​​Nozzle; 30. Corrugated plate; 31. Flow guide hole; 32. Activated carbon adsorption layer; 33. Resin adsorption layer; 34. Flow guide plate; 35. Wire mesh demister; 36. Porous partition plate. Detailed Implementation

[0035] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present utility model.

[0036] Example 1

[0037] like Figures 1 to 6As shown, a multi-stage treatment device for dichlorosan production tail gas includes a catalytic reactor 1, a water spray tower 2, an alkaline spray tower 3, and an adsorption tower 4 connected in series. The outlet of the adsorption tower 4 is connected to an exhaust pipe 5. The exhaust pipe 5 is connected to the inlet of the catalytic reactor 1 and an exhaust chimney 8 via a gas circulation pipe 6 and a gas discharge pipe 7, respectively. A first electric valve 9 and a second electric valve 10 are respectively installed on the gas circulation pipe 6 and the gas discharge pipe 7. A VOCs detector 11 is installed on the exhaust pipe 5, and the VOCs detector 11 is interlocked with the first electric valve 9 and the second electric valve 10. The tail gas is sequentially chemically degraded in the catalytic reactor 1, absorbed and neutralized by the water spray tower 2 and the alkaline spray tower 3, and deeply adsorbed by the adsorption tower 4, achieving the staged removal of complex components in the tail gas and improving the tail gas treatment efficiency.

[0038] The catalytic reaction vessel 1 is provided with a multi-layer catalyst packing layer 12; the catalytic reaction vessel 1 is provided with a gas distribution mechanism, which includes a gas distribution plate 14 connected to the gas inlet pipe 13 and multiple main gas outlet holes 15 provided on the gas distribution plate 14; a gas outlet pipe 16 is connected to the side wall of the gas distribution plate 14, the end of the gas outlet pipe 16 is closed, and multiple auxiliary gas outlet holes 17 are provided on the side wall of the gas outlet pipe 16; multiple turbulence fins 18 are provided in the inner circumferential direction of both the main gas outlet holes 15 and the auxiliary gas outlet holes 17. The above arrangement ensures that the reaction gas and the catalyst packing are in full contact, thereby improving the efficiency of the catalytic oxidation reaction.

[0039] The gas inlet of the catalytic reaction tank 1 is connected to the preheater 19. The preheater 19 is equipped with hollow spiral blades 20 and multiple parallel gas delivery pipes 21 that penetrate the hollow spiral blades 20. The hollow spiral blades 20 and the jacket of the preheater 19 are both connected to heat exchange medium pipes 22. The combined arrangement of the hollow spiral blades 20 and the gas delivery pipes 21 improves the preheating efficiency and reduces energy consumption.

[0040] Both the water spray tower 2 and the alkali spray tower 3 are equipped with gas distributors 23 at their lower parts; both are equipped with spraying mechanisms at their upper parts. The bottom of the alkali spray tower 3 is sequentially connected to a pH adjustment tank 24 and a filter 25. The outlet of the filter 25 is connected to the spraying mechanism at the top of the alkali spray tower 3 via a reflux pump 26 and a reflux pipe 27, realizing the recycling of alkali solution and reducing waste liquid discharge and chemical reagent consumption. The spraying mechanism includes multiple layers of spray pipes 28, each with multiple nozzles 29, and the nozzles 29 on each layer of spray pipes 28 have a different inclination angle. The arrangement of gas distributors 23 and multiple layers of nozzles 29 in the water spray tower 2 and the alkali spray tower 3 increases the gas-liquid contact area and reaction time, thereby improving the removal rate of pollutants in the exhaust gas.

[0041] The inner walls of the water spray tower 2 and the alkali spray tower 3 are provided with downwardly inclined corrugated plates 30, and the surface of the corrugated plates 30 is provided with multiple guide holes 31; the adsorption tower 4 is provided with an activated carbon adsorption layer 32 and a resin adsorption layer 33 alternately; the activated carbon adsorption layer 32 can adsorb non-polar VOCs, and the resin adsorption layer 33 adsorbs polar organic matter, and the two work together to enhance the adsorption capacity of pollutants; the combined arrangement of the corrugated plates 30 and the guide channels 31 extends the gas path, enhances turbulence, and improves adsorption efficiency.

[0042] In this embodiment, the gas delivery pipe 21 is provided with a guide hole 34 on its inner wall to extend the gas delivery path, improve preheating efficiency, and reduce energy consumption in the catalytic reaction process.

[0043] In this embodiment, a wire mesh demister 35 is provided at the air outlet of the water spray tower 2 and the alkali spray tower 3 to prevent the spray tower droplets from entering the adsorption tower and to protect the activity of the adsorbent.

[0044] In this embodiment, a porous partition plate 36 is provided between the activated carbon adsorption layer 32 and the resin adsorption layer 33. On the one hand, it can prevent the adsorption layer materials from mixing, and on the other hand, it can maintain the uniformity of airflow and improve the adsorption efficiency of exhaust gas.

[0045] The above description of the disclosed embodiments enables those skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A multi-stage treatment device for dichlorosan production tail gas, characterized in that: It includes a catalytic reaction tank, a water spray tower, an alkali spray tower, and an adsorption tower connected in series, with the gas outlet of the adsorption tower connected in sequence to an exhaust pipe and an exhaust chimney; The catalytic reaction vessel is equipped with multiple layers of catalyst packing; Both the water spray tower and the alkali spray tower are equipped with gas distributors at their lower parts; both the water spray tower and the alkali spray tower are equipped with spraying mechanisms at their upper parts. The bottom of the alkali spray tower is connected in sequence to a pH adjustment tank and a filter. The outlet of the filter is connected to the spraying mechanism at the top of the alkali spray tower through a reflux pump and a reflux pipe. The spraying mechanism includes multiple layers of spray pipes, each with multiple nozzles, and the nozzles on each layer of spray pipes have a different inclination angle. Both the water spray tower and the alkali spray tower have downward-sloping corrugated plates on their inner walls, and the surface of the corrugated plates has multiple flow guide holes; the adsorption tower has alternating activated carbon adsorption layers and resin adsorption layers inside.

2. A multi-stage treatment device for dichlorosan production tail gas according to claim 1, characterized in that: The lower part of the catalytic reaction tank is provided with a gas distribution mechanism, which includes a gas distribution plate connected to the gas inlet pipe and multiple main gas outlet holes provided on the gas distribution plate.

3. A multi-stage treatment device for dichlorosan production tail gas according to claim 2, characterized in that: The air distribution plate has an air outlet pipe connected to its side wall. The end of the air outlet pipe is closed, and the side wall of the air outlet pipe is provided with multiple auxiliary air outlet holes.

4. A multi-stage treatment device for dichlorosan production tail gas according to claim 3, characterized in that: Both the main air outlet and the auxiliary air outlet are provided with multiple turbulence fins in the inner circumference.

5. A multi-stage treatment device for dichlorosan production tail gas according to claim 1, characterized in that: The gas inlet of the catalytic reaction vessel is connected to a preheater. The preheater is equipped with hollow spiral blades and multiple parallel gas delivery pipes that penetrate the hollow spiral blades. The hollow spiral blades and the jacket of the preheater are both connected to heat exchange medium pipes.

6. A multi-stage treatment device for dichlorosan production tail gas according to claim 5, characterized in that: The gas delivery pipe has guide vanes on its inner wall.

7. A multi-stage treatment device for dichlorosan production tail gas according to claim 1, characterized in that: The water spray tower and the alkali spray tower are equipped with wire mesh demisters at their air outlets.

8. A multi-stage treatment device for dichlorosan production tail gas according to claim 1, characterized in that: A porous partition plate is provided between the activated carbon adsorption layer and the resin adsorption layer.

9. A multi-stage treatment device for dichlorosan production tail gas according to claim 1, characterized in that: The exhaust pipe is connected to the air inlet of the catalytic reactor and the exhaust chimney through a gas circulation pipe and a gas discharge pipe, respectively; the gas circulation pipe and the gas discharge pipe are respectively equipped with a first electric valve and a second electric valve, and the exhaust pipe is equipped with a VOCs detector, which is interlocked with the first electric valve and the second electric valve, respectively.

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