A filter for the bottom of an absorption tower
By installing a multi-chamber filter at the bottom of the absorption tower and using a high-speed jet from the injection nozzle to flush the sieve holes, the problem of equipment blockage and reduced separation efficiency caused by solid impurities at the bottom of the absorption tower was solved. This achieved self-cleaning and stable operation of the filter, ensuring the high purity of maleic anhydride products.
Patent Information
- Application Number
- CN202522638408.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-12-12
- Publication Date
- 2026-11-06
- Estimated Expiration
- 2035-12-12
AI Technical Summary
In the existing maleic anhydride production process, the solvent at the bottom of the absorption tower contains a large amount of solid impurities, which leads to easy clogging and wear of subsequent equipment, reduced separation efficiency and affected product purity. In addition, the existing filters are prone to clogging and the backwashing effect is not ideal, which cannot meet the requirements of long-term, continuous and stable operation.
A filter for the bottom of an absorption tower is designed, with a first and a second partition wall to divide the filter cavity into a first, second, and a third chamber. A high-speed jet is formed by the injection port to flush the sieve holes, and combined with sieve filtration, it achieves efficient interception and self-cleaning of solid impurities.
It effectively prevents sieve clogging, achieves continuous and stable operation, reduces system maintenance, ensures stable operation and separation efficiency of subsequent equipment, and guarantees high purity of maleic anhydride products.
Smart Images
Figure CN224937948U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of maleic anhydride absorption tower bottom purification, and more specifically, to a filter for the bottom of an absorption tower. Background Technology
[0002] In the production of maleic anhydride, the absorption tower is one of the key pieces of equipment, used to absorb the maleic anhydride gas generated in the reaction. For example... Figure 1 As shown, in the butane oxidation process for maleic anhydride, the raw material butane is vaporized and preheated, then mixed with preheated air and water vapor, and undergoes an oxidation reaction in a reactor containing a catalyst to produce maleic anhydride. The reaction product, after cooling, enters an absorption tower, where it comes into countercurrent contact with a lean solvent flowing downwards. The maleic anhydride gas in the absorption tower is absorbed to form a rich solvent. The tail gas from the top of the absorption tower is sent to a post-treatment system, while the rich solvent at the bottom of the tower is subsequently sent to a flash distillation tower and a stripping tower for separation and purification, ultimately yielding the product maleic anhydride. The lean solvent is recycled.
[0003] However, this process is complex. Besides the target product, maleic anhydride, the reaction system also produces organic byproducts such as acetic acid, propionic acid, and furan. Additionally, trace impurities from the raw materials, polymers generated during the reaction, and coking particles are also present in the reaction gas. These impurities enter the absorption tower with the feed stream, and some solid particles accumulate in the rich solvent at the bottom of the tower, forming a slag-containing rich solvent. Current production processes lack efficient purification units for this slag-containing rich solvent. If these solid impurities are allowed to enter subsequent flash distillation towers, stripping towers, and other equipment, a series of operational problems will occur: First, impurities will clog pipes and valves and accelerate pump wear; second, impurities will contaminate the packing or trays of subsequent towers, significantly reducing their mass transfer efficiency; more seriously, impurities will continuously accumulate in the solvent circulation system, ultimately affecting the purity and quality of the maleic anhydride product.
[0004] Currently, although some absorption towers are equipped with filters, they generally suffer from problems such as the screen holes being easily clogged by sticky or angular impurities, unsatisfactory backwashing effects, and the need for frequent shutdowns for cleaning, which cannot meet the requirements for long-term, continuous, and stable operation.
[0005] These problems urgently need to be solved, therefore, this utility model provides a filter for the bottom of an absorption tower. Utility Model Content
[0006] The technical problem this invention aims to solve is: in existing maleic anhydride production processes, the solvent-rich bottom of the absorber contains a large amount of solid impurities, leading to clogging, wear, reduced separation efficiency, and compromised product purity in subsequent equipment. This invention provides a filter specifically designed for the bottom of the absorber. This filter not only efficiently traps solid impurities but also possesses self-cleaning capabilities, effectively preventing sieve clogging, enabling continuous and stable operation, and reducing system maintenance.
[0007] The technical solution adopted by this utility model to solve its technical problem is: to provide a filter for the bottom of an absorption tower, wherein the filter is provided with a first partition wall and a second partition wall, and the inner cavity of the filter is divided into a first chamber, a second chamber and a third chamber by the first partition wall and the second partition wall, wherein the first partition wall is provided with a spray port facing the second partition wall, and the second partition wall is provided with a sieve hole.
[0008] In this embodiment, specifically, the inlet diameter of the injection port is larger than the outlet diameter.
[0009] In this embodiment, specifically, the diameter of the sieve hole is smaller than the outlet diameter of the injection port.
[0010] In this embodiment, specifically, the sieve holes are formed in the upper part of the second partition wall, and the lower part of the second partition wall is a sealing wall.
[0011] In this embodiment, specifically, the depth of the first chamber is greater than that of the second chamber and the third chamber, and the top of the first chamber away from the second chamber is connected to a feed pipe, through which a solvent rich in impurities flows out.
[0012] In this embodiment, specifically, the lower side of the second chamber is provided with an inclined slag-gathering surface, and a slag outlet pipe is provided in the middle of the slag-gathering surface, through which the solvent rich in impurities is discharged.
[0013] In this embodiment, specifically, a discharge pipe is provided on the lower side of the third chamber, the third chamber is detachably installed on one side of the second chamber, a first mounting plate is installed on one side of the second chamber, a second mounting plate is installed on one side of the third chamber, and the first mounting plate and the second mounting plate are fixedly connected by bolts.
[0014] In this embodiment, specifically, the top of the filter is connected to the absorption tower via a pipeline, the bottom of the absorption tower is provided with a slag discharge pipe, and valves and pumps are provided on the pipeline from the slag discharge pipe to the feed pipe.
[0015] In this embodiment, specifically, the lower part of the absorption tower is provided with a rich solvent discharge pipe and a gas feed pipe, the top of the absorption tower is provided with a gas outlet, and the upper side of the absorption tower is provided with a lean solvent feed pipe.
[0016] In this embodiment, specifically, the absorption tower is provided with packing in the middle, and a distributor is provided at the top of the packing.
[0017] The beneficial effects of this utility model are as follows: This utility model provides a filter for the bottom of an absorption tower. The filter has a first partition wall and a second partition wall. The inner cavity of the filter is divided into a first chamber, a second chamber, and a third chamber by the first partition wall and the second partition wall. The first partition wall has a spray port facing the second partition wall, and the second partition wall has sieve holes. Through the spray port design on the first partition wall, a high-speed jet is formed by fluid pressure, which directly acts on the sieve hole area of the second partition wall, generating a continuous and powerful scouring effect. This online self-cleaning mechanism can effectively prevent sticky and irregular impurities from being embedded and retained in the sieve holes. Attached Figure Description
[0018] The present invention will be further described below with reference to the accompanying drawings and embodiments.
[0019] In the picture: Figure 1 A process flow diagram for the preparation of maleic anhydride; Figure 2 This is a schematic diagram of the absorption tower and filter of this utility model; Figure 3 for Figure 2 Schematic diagram of the structure of the medium absorption tower; Figure 4 for Figure 2 A schematic diagram of the structure of the intermediate filter; 1. Absorption tower; 11. Rich solvent discharge pipe; 12. Gas outlet; 13. Lean solvent inlet pipe; 14. Gas inlet pipe; 15. Slag-containing discharge pipe; 151. Valve; 152. Pump; 16. Distributor; 17. Packing; 2. Filter; 21. First partition wall; 211. Injection port; 22. Second partition wall; 221. Screen hole; 23. First chamber; 231. Feed pipe; 24. Second chamber; 241. Slag collection surface; 242. Slag discharge pipe; 243. First mounting plate; 25. Third chamber; 251. Discharge pipe; 252. Second mounting plate. Detailed Implementation
[0020] To make the technical problem to be solved, the technical solution, and the beneficial effects of this utility model clearer, the present utility model will now be described in detail with reference to the accompanying drawings. This drawing is a simplified schematic diagram, illustrating only the basic aspects of the present utility model, and therefore only shows the components relevant to the present utility model. Obviously, the described embodiments are only some, not all, of the embodiments of this utility model. All other embodiments obtained by those skilled in the art based on the embodiments of this utility model without creative effort are within the scope of protection of this utility model.
[0021] like Figure 1-2As shown, the lower part of the absorption tower 1 is equipped with a rich solvent discharge pipe 11 and a gas feed pipe 14, the top of the absorption tower 1 is equipped with a gas outlet 12, and the upper side of the absorption tower 1 is equipped with a lean solvent feed pipe 13. The bottom of the absorption tower 1 is equipped with a slag discharge pipe 15, and a valve 151 and a pump 152 are installed on the pipeline from the slag discharge pipe 15 to the feed pipe 231. The middle part of the absorption tower 1 is equipped with packing 17, and the top of the packing 17 is equipped with a distributor 16.
[0022] In this embodiment, butane is vaporized in a butane vaporizer and superheated in a butane superheater. It then undergoes an oxidation reaction with preheated air and a co-catalyst in a reactor to generate a reaction gas containing maleic anhydride. This reaction gas is cooled by air cooling and enters the absorption tower 1. The lean solvent enters through the lean solvent feed pipe 13, is evenly distributed by the distributor 16, and then comes into countercurrent contact with the reaction gas on the surface of the packing 17, absorbing maleic anhydride to form a rich solvent. The rich solvent at the bottom of the absorption tower 1 is divided into two streams: one stream, containing no impurities, is discharged through the rich solvent outlet pipe 11; the other stream, containing slag, is transported through the slag outlet pipe 15, valve 151, and pump 152 to the feed pipe 231 of the filter 2, and then enters the first chamber 23.
[0023] like Figure 2-4 As shown, this utility model provides a filter 2 for the bottom of an absorption tower. The filter 2 is provided with a first partition wall 21 and a second partition wall 22. The inner cavity of the filter 2 is divided into a first chamber 23, a second chamber 24 and a third chamber 25 by the first partition wall 21 and the second partition wall 22. The first partition wall 21 has a spray port 211 facing the second partition wall 22, and the second partition wall 22 has a sieve hole 221.
[0024] In this embodiment, specifically, the inlet diameter of the jet nozzle 211 is larger than the outlet diameter.
[0025] In this embodiment, specifically, the diameter of the sieve hole 221 is smaller than the outlet diameter of the spray nozzle 211.
[0026] In this embodiment, specifically, the sieve hole 221 is opened in the upper part of the second partition wall 22, and the lower part of the second partition wall 22 is a sealing wall.
[0027] In this embodiment, specifically, the depth of the first chamber 23 is greater than that of the second chamber 24 and the third chamber 25. The top of the first chamber 23 on the side away from the second chamber 24 is connected to a feed pipe 231, and the solvent rich in impurities flows out from the feed pipe 231.
[0028] In this embodiment, specifically, the lower side of the second chamber 24 is provided with an inclined slag-gathering surface 241, and a slag outlet pipe 242 is provided in the middle of the slag-gathering surface 241, through which the rich solvent containing impurities is discharged.
[0029] In this embodiment, specifically, a discharge pipe 251 is provided on the lower side of the third chamber 25. The third chamber 25 is detachably installed on one side of the second chamber 24. A first mounting plate 243 is installed on one side of the second chamber 24, and a second mounting plate 252 is installed on one side of the third chamber 25. The first mounting plate 243 and the second mounting plate 252 are fixedly connected by bolts.
[0030] The working process of a filter used at the bottom of an absorption tower according to this utility model is as follows: During filtration, the slag discharge pipe 242 is opened. Inside the filter 2, the rich solvent forms a jet through the spray port 211 of the first partition wall 21 and enters the second chamber 24. During the jet process, most impurities settle due to inertia and gravity. Subsequently, the rich solvent enters the third chamber 25 through the sieve holes 221 at the top of the second partition wall 22. The sieve holes 221 intercept the remaining fine particulate impurities. The impurities settle to the slag accumulation surface 241 in the second chamber 24 and are discharged through the slag discharge pipe 242. The filtered clean rich solvent is discharged from the discharge pipe 251 of the third chamber 25 and enters the desorption tower to continue the subsequent processes.
[0031] When it is necessary to clean filter 2, unscrew the bolts between the first mounting plate 243 and the second mounting plate 252, and remove the third chamber 25 from the second chamber 24. Then, each chamber and partition wall can be thoroughly cleaned. After cleaning, reassemble the filter 2 with bolts.
[0032] The above description is only a preferred embodiment of this utility model and is not intended to limit this utility model. For those skilled in the art, The beneficial effects of this utility model for a filter at the bottom of an absorption tower are as follows: 1. This utility model is directly installed on the slag discharge pipe 15 at the bottom of the absorption tower 1. Through multi-chamber graded separation and filtration through sieve 221, it can efficiently intercept solid impurities such as polymers and coking particles in the solvent-rich medium, preventing impurities from entering the subsequent flash tower and desorption tower. It effectively solves the problems of pipeline blockage, pump wear, and tower packing contamination caused by impurities, ensuring the stable operation and separation efficiency of subsequent processes.
[0033] 2. By setting a jet nozzle 211 on the first partition wall 21, a high-speed jet is formed using fluid pressure, which directly acts on the screen hole 221 area of the second partition wall 22, generating continuous and powerful scouring. This online self-cleaning mechanism effectively prevents sticky and irregular impurities from being embedded and retained in the screen holes, solving the problem of easy clogging of traditional filter screen holes. At the same time, the third chamber 25, through the detachable design of the first mounting plate 243 and the second mounting plate 252, makes thorough cleaning and maintenance very convenient.
[0034] 3. Because filter 2 can operate stably for a long time without easily clogging and is easy to maintain, it significantly reduces unplanned downtime caused by filter problems, ensuring continuous operation of the maleic anhydride production line. At the same time, by effectively removing solid impurities, it avoids the accumulation of impurities in the solvent circulation system, providing a strong guarantee for obtaining high-purity maleic anhydride products.
[0035] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.
[0036] It should be noted that the terms "first," "second," etc., used in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of this application described herein can be implemented in sequences other than those illustrated or described herein.
[0037] Based on the above-described preferred embodiments of this utility model, and through the foregoing description, those skilled in the art can make various changes and modifications without departing from the scope of this utility model. The technical scope of this utility model is not limited to the contents of the specification, but must be determined according to the scope of the claims.
Claims
1. A filter for the bottom of an absorption tower, characterized in that, The filter (2) is provided with a first partition wall (21) and a second partition wall (22). The inner cavity of the filter (2) is divided into a first chamber (23), a second chamber (24) and a third chamber (25) by the first partition wall (21) and the second partition wall (22). The first partition wall (21) has a spray port (211) facing the second partition wall (22), and the second partition wall (22) has a sieve hole (221).
2. A filter for the bottom of an absorption tower according to claim 1, characterized in that, The inlet diameter of the jet nozzle (211) is larger than the outlet diameter.
3. A filter for the bottom of an absorption tower according to claim 1, characterized in that, The diameter of the sieve hole (221) is smaller than the outlet diameter of the spray nozzle (211).
4. A filter for the bottom of an absorption tower according to claim 1, characterized in that, The sieve hole (221) is opened on the upper part of the second partition wall (22), and the lower part of the second partition wall (22) is a sealing wall.
5. A filter for the bottom of an absorption tower according to claim 1, characterized in that, The depth of the first chamber (23) is greater than that of the second chamber (24) and the third chamber (25). The top of the first chamber (23) away from the second chamber (24) is connected to a feed pipe (231), and the solvent rich in impurities flows out from the feed pipe (231).
6. A filter for the bottom of an absorption tower according to claim 1, characterized in that, The second chamber (24) has an inclined slag-gathering surface (241) on its lower side, and a slag outlet pipe (242) is provided in the middle of the slag-gathering surface (241). The rich solvent containing impurities is discharged from the slag outlet pipe (242).
7. A filter for the bottom of an absorption tower according to claim 1, characterized in that, The third chamber (25) is provided with a discharge pipe (251) on its lower side. The third chamber (25) is detachably installed on one side of the second chamber (24). A first mounting plate (243) is installed on one side of the second chamber (24), and a second mounting plate (252) is installed on one side of the third chamber (25). The first mounting plate (243) and the second mounting plate (252) are fixedly connected by bolts.
8. A filter for the bottom of an absorption tower according to claim 5, characterized in that, The filter (2) is connected to the absorption tower (1) via a pipeline at the top. The absorption tower (1) is provided with a slag discharge pipe (15) at the bottom. A valve (151) and a pump (152) are provided on the pipeline from the slag discharge pipe (15) to the feed pipe (231).
9. A filter for the bottom of an absorption tower according to claim 8, characterized in that, The absorption tower (1) is provided with a rich solvent outlet pipe (11) and a gas inlet pipe (14) at the bottom, a gas outlet (12) at the top, and a lean solvent inlet pipe (13) on the upper side of the absorption tower (1).
10. A filter for the bottom of an absorption tower according to claim 9, characterized in that, The absorption tower (1) is provided with packing (17) in the middle, and a distributor (16) is provided on the top of the packing (17).