Multi-channel adsorption tower and desorption regeneration method

Abstract

The invention provides a multi-channel type adsorption tower. The multi-channel type adsorption tower comprises a tower body, an upper sealing head, a lower sealing head, a combined layer plate, a combined partition plate, a supporting plate, porcelain balls and an adsorbent. The interior of the adsorption tower is sequentially divided into a feeding chamber, a first-stage adsorption chamber, a second-stage adsorption chamber, a third-stage adsorption chamber and a discharging chamber by combined layer plates from bottom to top; each adsorption chamber in the adsorption tower is equally divided into four unit chambers by combined partition plates; the adsorption chambers are filled with adsorbents, and agent discharging openings are formed in the outer sides of the adsorption chambers; a feeding hole is formed in the bottom of the lower sealing head, a discharging hole is formed in the top of the upper sealing head, and the feeding cavity and the discharging cavity are filled with porcelain balls; according to the arrangement of the combined layer plates and the combined partition plates, the interior of the adsorption tower can be divided into two material paths. The invention further provides a desorption regeneration method for the adsorbent through a liquid flushing and nitrogen purging combined process. The adsorption efficiency and the adsorption uniformity can be improved, and the adsorption process and the desorption process are synchronously carried out.

Description

Technical field:

[0001] The invention relates to the field of chemical equipment, and in particular to a multi-channel adsorption tower and a desorption regeneration method. Background technology:

[0002] Sulfur exists in petrochemical products in the form of elemental sulfur, hydrogen sulfide, mercaptans, sulfides, disulfides and thiophene. In the process of oil refining, these sulfides have a significant impact on product quality, processing, equipment corrosion and the environment. With the increasing global attention to environmental protection and sustainable development, the desulfurization process of petrochemical products has attracted more and more attention. Common desulfurization processes include hydrodesulfurization, adsorption desulfurization or oxidative desulfurization. Among them, adsorption desulfurization has attracted widespread attention due to its advantages such as low process cost, no hydrogen consumption, no change in product properties, easy adsorbent regeneration and mild reaction conditions.

[0003] Adsorption desulfurization is a technology that uses adsorbents in an adsorption tower to selectively adsorb sulfides in materials. The selected adsorbent is the core of its desulfurization technology. The solid adsorbent materials that are widely studied at present include carbon materials, molecular sieves and metal oxides. Among them, alumina is an adsorbent material that has been used for adsorption desulfurization earlier. It has the advantages of high efficiency, environmental protection, regeneration and good desulfurization effect. Regeneration is an effective method for treating adsorbent materials. The main adsorbent regeneration methods include thermal regeneration, wet oxidation regeneration, solvent regeneration and biological regeneration. Among them, thermal regeneration is the most widely used adsorbent material regeneration method in industry. It has the advantages of good general performance, short regeneration time and high regeneration efficiency, but it generally has the problem of large heat loss.

[0004] The design of the adsorption tower largely determines the desulfurization effect of the adsorption desulfurization process, but the current adsorption towers generally face challenges such as too short adsorption path, uneven adsorption distribution of adsorbents, the need for frequent replacement of adsorbents, and poor adsorption desulfurization effect.

[0005] Therefore, it is particularly important to design an adsorption tower that is efficient, environmentally friendly, time-saving and can improve the utilization rate of the adsorbent. Summary of the invention:

[0006] The implementation purpose of the present invention is to provide a multi-channel adsorption tower and a desorption regeneration method, which can extend the adsorption path of the adsorption tower, realize the regeneration and uninterrupted adsorption of the adsorbent in the tower, and thus improve the adsorption desulfurization efficiency, aiming to solve the following problems: (1) the problems of insufficient adsorbent utilization and easy wear of the adsorbent caused by uneven material dispersion in the traditional adsorption tower; (2) the problems of too short adsorption path and low space utilization of the adsorption tower caused by simple stacking and unreasonable arrangement of the adsorbent; (3) the problems of discontinuity of adsorption caused by the separation of the adsorption tower and the desorption tower, small adsorption processing capacity, time-consuming and labor-intensive, and inconvenient operation; (4) the problems of large heat loss and harsh operating conditions in the adsorbent thermal regeneration process.

[0007] The specific technical scheme of the present invention is:

[0008] A multi-channel adsorption tower, characterized in that the adsorption tower comprises: a tower body, an upper head, a lower head, a combined layer plate, a combined partition plate, a support plate, a porcelain ball and an adsorbent;

[0009] The adsorption tower is divided into a feed chamber, a primary adsorption chamber, a secondary adsorption chamber, a tertiary adsorption chamber and a discharge chamber by the combined layers from bottom to top; the feed chamber and the discharge chamber are equally divided into two material unit chambers by the partition, and each adsorption chamber is equally divided into four material unit chambers by the combined partition; the feed chamber is located in the lower head, the adsorption chambers of each level are located in the tower body, and the discharge chamber is located in the upper head; a support plate is welded to the inner wall of the adsorption tower for supporting the combined layers and the combined partitions; the two material unit chambers of the feed chamber are respectively provided with a first feed port and a second feed port as inlet unit chambers; the two material unit chambers of the discharge chamber are respectively provided with a first discharge port and a second discharge port as outlet unit chambers;

[0010] The combined layer plate is composed of a fan-shaped partition plate and a fan-shaped porous plate.

[0011] The combined partition is composed of a square partition and a square grid plate.

[0012] The adsorption chambers are filled with alkaline alumina adsorbent, each level of adsorption chamber is filled with adsorbent particles of different particle sizes, and each level of adsorption chamber is provided with two unloading ports.

[0013] The inlet unit chamber and the outlet unit chamber are filled with porcelain balls.

[0014] Furthermore, each layer of the combined layer plates is composed of two fan-shaped partitions and two fan-shaped porous plates, the fan-shaped partitions and the fan-shaped porous plates are arranged at intervals, and the fan-shaped partitions and the fan-shaped porous plates in each adjacent layer of the combined layer plates are staggered along the axial direction of the tower body.

[0015] Furthermore, each layer of combined partitions of each adsorption chamber is composed of two square partitions and two square grid plates, the square partitions and the square grid plates are arranged at intervals, and the square partitions and square grid plates in each adjacent layer of combined partitions are staggered along the axial direction of the tower body, wherein one side of the square partition is connected to the support plate by a hinge; the feed chamber and the discharge chamber are each separated by a square partition.

[0016] Furthermore, the thickness of the adsorption layer in the first-stage adsorption chamber is 1.5-3m, and the particle size of the adsorbent particles is 6-10mm, the thickness of the adsorption layer in the second-stage adsorption chamber is 1-2m, and the particle size of the adsorbent particles is 4-8mm, and the thickness of the adsorption layer in the third-stage adsorption chamber is 0.5-1.5m, and the particle size of the adsorbent particles is 2-5mm.

[0017] Furthermore, the through-hole equivalent diameter of the sector-shaped porous plate and the square grid plate is 2-5 mm, the opening rate is 40%-70%, and the single hole diameter of the sector-shaped porous plate and the single rectangular hole of the square grid plate are smaller than the adjacent adsorbent particle diameter.

[0018] Furthermore, the desorption and regeneration method of the adsorbent in the multi-channel adsorption tower comprises the following steps:

[0019] The material to be purified enters from the first feed port and the second feed port, wherein the material entering from the first feed port enters the material unit chamber through the fan-shaped porous plate at the bottom of the first adsorption chamber connected to the first feed port, and then enters the material unit chambers of the second adsorption chamber and the third adsorption chamber in sequence along the square grid plate of the material unit chamber and the fan-shaped porous plates and square grid plates of each layer, and the clean material after being adsorbed by the adsorbent in the three-layer adsorption chamber enters the first discharge port connected to the fan-shaped porous plate at the top of the third adsorption chamber, and is discharged from the first discharge port, forming a first path for material transportation;

[0020] At the same time, the material entering from the second feed port enters the material unit chamber through the fan-shaped porous plate at the bottom of the first-stage adsorption chamber connected to the second feed port, and then enters the material unit chambers of the second-stage adsorption chamber and the third-stage adsorption chamber in sequence along the square grid plate of the material unit chamber. The clean material adsorbed by the adsorbent in the three-layer adsorption chamber enters the second discharge port connected to the fan-shaped porous plate at the top of the third-stage adsorption chamber, and is discharged from the second discharge port, forming a second path for material transportation;

[0021] When the adsorbent in the first path is saturated with adsorption, the feeding to the first feed port is stopped, and the remaining material in the first path is extracted from the first feed port; after all the materials are extracted, low-temperature water is first injected from the first discharge port to flush the adsorbent in the first path, and then low-temperature nitrogen is introduced into the first discharge port to purge the adsorbent after the flushing is completed, thereby completing the desorption and regeneration treatment of the alkaline alumina adsorbent through the combined process of liquid flushing and nitrogen purge, and the adsorption operation can be carried out only after the adsorbent is cooled after regeneration; the adsorbent in the second path is subjected to the same desorption and regeneration treatment after adsorption saturation.

[0022] Furthermore, the two paths perform adsorption operation simultaneously, or the two paths perform desorption regeneration simultaneously, or the two paths perform adsorption operation and desorption regeneration separately.

[0023] Furthermore, the flow rate of the material to be purified in the tower is 0.001-0.1 m / s, and the flow rate of water and nitrogen in the tower is 0.05-0.5 m / s.

[0024] Furthermore, the water flushing temperature is 40-80° C., the flushing time is 12-24 hours, the nitrogen purge temperature is 50-70° C., and the purge time is 20-40 minutes.

[0025] Effective benefits:

[0026] Compared with the prior art, this application has the following technical effects:

[0027] (1) The adsorption path formed by the arrangement of the combined layer plates and combined partitions in the adsorption tower can significantly prolong the contact time between the material and the adsorbent and improve the utilization rate of the adsorbent. At the same time, the through holes of the fan-shaped porous plate and the square grid plate not only have a flow-guiding effect, but also can effectively disperse the material, eliminate the dead zone of the adsorption tower, and significantly improve the adsorption purification effect.

[0028] (2) The two paths set in the adsorption tower can realize adsorption and desorption simultaneously, keep the adsorption process uninterrupted, and significantly increase the material processing capacity of the adsorption system per unit time.

[0029] (3) The alkaline alumina particles are selected as the adsorbent and arranged in grades according to the particle size, which can effectively remove the sulfur-containing compounds in the material and improve the product quality. In addition, the adsorption performance loss rate of the alkaline alumina adsorbent is low after regeneration, and the regeneration conditions are simple and the operation is convenient.

[0030] (4) The combined regeneration process of low-temperature liquid medium flushing and low-temperature nitrogen purge can not only reduce the heat loss of the adsorbent material, but also significantly restore the adsorption performance of the adsorbent and improve the recycling rate of the adsorbent. Description of the drawings:

[0031] The accompanying drawings are used to provide a further understanding of the present invention. They only constitute a part of this specification to further explain the present invention, and do not constitute a limitation of the present invention.

[0032] Figure 1 It is a schematic diagram of the structure of a multi-channel adsorption tower and two material conveying paths of the present invention;

[0033] Figure 2 A three-dimensional diagram of a multi-channel adsorption tower of the present invention;

[0034] Among them: 1-tower body; 2-upper head; 3-lower head; 4-drug discharge port; 21-first discharge port; 22-second discharge port; 31-first feed port; 32-second feed port.

[0035] Figure 3 It is a schematic diagram of simultaneous adsorption operation and desorption regeneration of a multi-channel adsorption tower of the present invention;

[0036] Figure 4 It is a cross-sectional schematic diagram of a multi-channel adsorption tower of the present invention after being filled with adsorbent and porcelain balls;

[0037] Among them: 12-inlet unit chamber; 13-primary adsorption chamber; 14-secondary adsorption chamber; 15-tertiary adsorption chamber; 16-exit unit chamber.

[0038] Figure 5 It is a schematic diagram of the fan-shaped porous plate structure;

[0039] Among them: 61- fan-shaped porous plate gas-liquid through hole.

[0040] Figure 6 Schematic diagram of the square grid plate structure.

[0041] Wherein: 71-square grid plate gas-liquid through hole; 72-hinge. Specific implementation method:

[0042] In order to make the purpose, technical solution and technical advantages of the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein explain the present invention, but do not limit the present invention.

[0043] The specific implementation of the present invention is described in detail below in conjunction with specific embodiments.

[0044] Embodiment 1:

[0045] A petrochemical plant uses the adsorption tower and desorption regeneration method of the present invention to desulfurize alkylate oil.

[0046] Process conditions: total sulfur content in alkylate oil reaches 20-50 mg / L, 65℃ process water, 65℃ low-temperature nitrogen.

[0047] Device conditions: Device as Figure 1-6 As shown. The particle sizes of the alkaline alumina adsorbent particles filled in the primary adsorption chamber, the secondary adsorption chamber and the tertiary adsorption chamber are 10mm, 8mm and 5mm respectively. The equivalent pore size of the sector porous plate and the square grid plate is 5mm. The thickness of the adsorption layer in the primary adsorption chamber is 1.5m, the thickness of the adsorption layer in the secondary adsorption chamber is 1m, and the thickness of the adsorption layer in the tertiary adsorption chamber is 0.8m. The flow rate of alkylate oil in the tower is 0.005m / s, and the flow rate of process water and nitrogen in the tower is 0.5m / s.

[0048] Operation process: sulfur-containing alkylate oil enters from the first feed port and the second feed port, flows through the first path and the second path, and is adsorbed and desulfurized by the adsorbent in the three-layer adsorption chamber. The clean alkylate oil after adsorption is discharged from the first discharge port and the second discharge port, and the total sulfur content in the alkylate oil at the discharge port is detected at the same time; when the total sulfur content at the discharge port exceeds 10 mg / L, the adsorbent in the tower is saturated with adsorption, and the second feed port continues to input alkylate oil, and the input of alkylate oil to the first feed port is stopped, and the remaining alkylate oil in the first path is extracted from the first feed port. Adsorbent regeneration operation: first, inject 65°C process water from the first discharge port to flush the adsorbent in the first path for 18 hours. After flushing, introduce 65°C nitrogen into the first discharge port to purge the adsorbent for 30 minutes. After the purge is completed, turn off the low-temperature nitrogen system. After the tower body is cooled for 30 minutes, start injecting sulfur-containing alkylate oil from the first feed port, and the purified gas is discharged through the first discharge port. When the desorption and regeneration of the adsorbent in the first path is completed, stop inputting alkylate oil into the second feed port, and continue to desorb and regenerate the adsorbent in the second path according to the above steps.

[0049] Determination method: The total sulfur was determined using SH / T 0253-1992 “Determination of total sulfur content in light petroleum products (coulometric method)”.

[0050] Application effect: After the alkylate oil is desulfurized by the method and device of the present invention, the total sulfur content can be reduced to below 3 mg / L; after the alkaline alumina adsorbent is regenerated, the saturated adsorption capacity of the adsorbent can reach 80% of the original adsorption capacity of the adsorbent, and the adsorption performance of the adsorbent is effectively restored.

[0051] Embodiment 2:

[0052] The method and device of the present invention are used in a regeneration process of a basic alumina adsorbent used in the desulfurization of natural gas in a refinery.

[0053] Process conditions: The hydrogen sulfide content in natural gas reaches 200mg / m 3, 70℃ process water, 70℃ low temperature nitrogen.

[0054] Device conditions: Device as Figure 1-6 As shown. The particle sizes of the alkaline alumina adsorbent particles filled in the primary adsorption chamber, the secondary adsorption chamber and the tertiary adsorption chamber are 9mm, 7mm and 4mm respectively. The equivalent pore size of the fan-shaped porous plate and the square grid plate is 4mm. The thickness of the adsorption layer in the primary adsorption chamber is 1.5m, the thickness of the adsorption layer in the secondary adsorption chamber is 1m, and the thickness of the adsorption layer in the tertiary adsorption chamber is 0.8m. The flow rate of natural gas in the tower is 0.002m / s, and the flow rate of process water and nitrogen in the tower is 0.2m / s.

[0055] Operation process: When the adsorbent in the first path is saturated with adsorption, stop inputting natural gas to the first feed port, and extract the remaining natural gas in the first path from the first feed port, and at the same time measure the hydrogen sulfide content of the natural gas after adsorption by the adsorbent, and then perform adsorbent regeneration operation. First, inject 70°C process water from the first discharge port to flush the adsorbent in the first path for 24 hours. After flushing, open the low-temperature nitrogen system valve, and then introduce 70°C nitrogen to the first discharge port to purge the adsorbent for 40 minutes. After the purge is completed, close the low-temperature nitrogen system, and start injecting the natural gas to be purified from the first feed port after the tower body cools for 30 minutes. The purified gas is discharged through the first discharge port, and the hydrogen sulfide content in the natural gas is measured after the adsorbent is saturated again.

[0056] Determination method: The iodine titration method of GB / T 17820-2018 is used to determine the hydrogen sulfide content in natural gas after adsorption by adsorbent.

[0057] Application effect: After the natural gas is desulfurized by the method and device of the present invention, the hydrogen sulfide content can be reduced to below 10 mg / L. After the alkaline alumina adsorbent is regenerated by the method and device of the present invention, the saturated adsorption capacity of the adsorbent is 13.47 mg / g, which is 82% of the original adsorption capacity of the adsorbent (16.39 mg / g). After a single regeneration, the adsorption performance loses 18%. The regeneration effect is good, and the adsorption performance of the adsorbent is effectively restored.

[0058] The above description is only a preferred embodiment of the present invention, and does not impose any limitation on the present invention. Any simple modification, change and equivalent transformation made to the above embodiment based on the technical essence of the present invention still falls within the protection scope of the technical solution of the present invention.

Claims

1. A multi-channel adsorption tower, It is characterized in that The adsorption tower comprises: a tower body, an upper head, a lower head, a combined layer plate, a combined partition plate, a support plate, a porcelain ball and an adsorbent; The adsorption tower is divided into a feed chamber, a primary adsorption chamber, a secondary adsorption chamber, a tertiary adsorption chamber and a discharge chamber by the combined layers from bottom to top; the feed chamber and the discharge chamber are equally divided into two material unit chambers by the partition, and each adsorption chamber is equally divided into four material unit chambers by the combined partition; the feed chamber is located in the lower head, the adsorption chambers of each level are located in the tower body, and the discharge chamber is located in the upper head; a support plate is welded to the inner wall of the adsorption tower for supporting the combined layers and the combined partitions; the two material unit chambers of the feed chamber are respectively provided with a first feed port and a second feed port as inlet unit chambers; the two material unit chambers of the discharge chamber are respectively provided with a first discharge port and a second discharge port as outlet unit chambers; The combined layer plate is composed of a fan-shaped partition plate and a fan-shaped porous plate. The combined partition is composed of a square partition and a square grid plate. The adsorption chambers are filled with alkaline alumina adsorbent, each level of adsorption chamber is filled with adsorbent particles of different particle sizes, and each level of adsorption chamber is provided with two unloading ports. The inlet unit chamber and the outlet unit chamber are filled with porcelain balls.

2. A multi-channel adsorption tower as described in claim 1, It is characterized in that Each layer of combined plates is composed of two fan-shaped partitions and two fan-shaped porous plates, which are arranged at intervals, and the fan-shaped partitions and fan-shaped porous plates in each adjacent layer of combined plates are staggered along the axial direction of the tower body.

3. A multi-channel adsorption tower as described in claim 1, It is characterized in that Each layer of combined partitions of each adsorption chamber is composed of two square partitions and two square grid plates, the square partitions and the square grid plates are arranged at intervals, and the square partitions and square grid plates in each adjacent layer of combined partitions are staggered along the axial direction of the tower body, wherein one side of the square partition is connected to the support plate by a hinge; the feed chamber and the discharge chamber are each separated by a square partition.

4. A multi-channel adsorption tower as described in claim 1, It is characterized in that The thickness of the adsorption layer in the primary adsorption chamber is 1.5-3m, and the particle size of the adsorbent particles is 6-10mm. The thickness of the adsorption layer in the secondary adsorption chamber is 1-2m, and the particle size of the adsorbent particles is 4-8mm. The thickness of the adsorption layer in the tertiary adsorption chamber is 0.5-1.5m, and the particle size of the adsorbent particles is 2-5mm.

5. A multi-channel adsorption tower as described in claim 1, It is characterized in that The through-hole equivalent diameter of the sector-shaped porous plate and the square grid plate is 2-5 mm, the opening rate is 40%-70%, and the single hole diameter of the sector-shaped porous plate and the single rectangular hole of the square grid plate are both smaller than the adjacent adsorbent particle diameter.

6. A method for desorption and regeneration of an adsorbent in a multi-channel adsorption tower as claimed in claim 1, wherein the method The following steps are involved: The material to be purified enters from the first feed port and the second feed port, wherein the material entering from the first feed port enters the material unit chamber through the fan-shaped porous plate at the bottom of the first adsorption chamber connected to the first feed port, and then enters the material unit chambers of the second adsorption chamber and the third adsorption chamber in sequence along the square grid plate of the material unit chamber and the fan-shaped porous plates and square grid plates of each layer, and the clean material after being adsorbed by the adsorbent in the three-layer adsorption chamber enters the first discharge port connected to the fan-shaped porous plate at the top of the third adsorption chamber, and is discharged from the first discharge port, forming a first path for material transportation; At the same time, the material entering from the second feed port enters the material unit chamber through the fan-shaped porous plate at the bottom of the first-stage adsorption chamber connected to the second feed port, and then enters the material unit chambers of the second-stage adsorption chamber and the third-stage adsorption chamber in sequence along the square grid plate of the material unit chamber and the fan-shaped porous plates and square grid plates of each layer. The clean material adsorbed by the adsorbent in the three-layer adsorption chamber enters the second discharge port connected to the fan-shaped porous plate at the top of the third-stage adsorption chamber, and is discharged from the second discharge port, forming a second path for material transportation; When the adsorbent in the first path is saturated with adsorption, the feeding to the first feed port is stopped, and the remaining material in the first path is extracted from the first feed port; after all the materials are extracted, low-temperature water is first injected from the first discharge port to flush the adsorbent in the first path, and then low-temperature nitrogen is introduced into the first discharge port to purge the adsorbent after the flushing is completed, thereby completing the desorption and regeneration treatment of the alkaline alumina adsorbent through the combined process of liquid flushing and nitrogen purge, and the adsorption operation can be carried out only after the adsorbent is cooled after regeneration; the adsorbent in the second path is subjected to the same desorption and regeneration treatment after adsorption saturation.

7. The method according to claim 6, It is characterized in that The two paths perform adsorption operation simultaneously, or the two paths perform desorption regeneration simultaneously, or the two paths perform adsorption operation and desorption regeneration separately.

8. The method according to claim 6, It is characterized in that The flow rate of the material to be purified in the tower is 0.001-0.1 m / s, and the flow rate of water and nitrogen in the tower is 0.05-0.5 m / s.

9. The method according to claim 6, It is characterized in that The water flushing temperature is 40-80°C, the flushing time is 12-24 hours, the nitrogen purge temperature is 50-70°C, and the purge time is 20-40 minutes.

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