Efficient methanol washing demisting device

Abstract

The utility model discloses an efficient methanol washing demisting device. The efficient methanol washing demisting device is provided with an inlet assembly, a U-shaped absorption tower disc, a folded plate demister and a coalescence demisting module from bottom to top, methanol synthesis gas uniformly rises along the section of the tower after being uniformly distributed by the fin distributor of the inlet assembly; methanol in the methanol synthesis gas is gradually transferred into the absorption liquid from bottom to top through a U-shaped absorption tower tray by utilizing the characteristic that water and methanol are infinitely mutually soluble and through sufficient gas-liquid mixing, so that an absorption liquid concentration gradient which is gradually increased from top to bottom is formed; the gas-liquid mass transfer effect is good under the same concentration gradient, the absorption efficiency is high, a methanol solution with the concentration being 60% or above is finally obtained at the tower bottom, after the washed methanol synthesis gas is subjected to double demisting through the folded plate demister and the coalescence demisting membrane block, entrainment in the methanol synthesis gas is effectively removed, and the methanol content in circulating gas is reduced.

Description

Technical Field

[0001] The utility model relates to the field of chemical production, in particular to a high-efficiency methanol water washing and demisting device in a methanol production process. Background Art

[0002] If the methanol content is too high, the methanol synthesis gas will circulate empty in the system, which will have a great impact on the device capacity, energy consumption, catalyst, venting volume, etc. Therefore, improving the absorption efficiency of the methanol water scrubber and reducing the methanol content in the circulating gas can increase the synthesis rate of fresh raw gas, which can greatly improve the methanol output capacity under the same device capacity.

[0003] Traditional methanol water washing towers use packing or tray bubbling absorption, which cannot form a clear absorption liquid concentration gradient that gradually increases from top to bottom. At the same time, it is also impossible to achieve a good gas-liquid mass transfer effect under the same concentration gradient, and the absorption efficiency is low, resulting in a high methanol content in the circulating gas. At the same time, the low-concentration methanol solution produced increases the load on the distillation tower in the subsequent process and increases production costs. The large amount of absorption solution entrained in the circulating gas causes the circulating machine to operate with liquid, creating a potential accident hazard. Utility Model Content

[0004] The utility model aims to provide a high-efficiency methanol water washing and demisting device, forming a clear absorption liquid concentration gradient that gradually increases from top to bottom, achieving a good gas-liquid mass transfer effect under the same concentration gradient, and improving the absorption efficiency of the absorption liquid for methanol.

[0005] The technical scheme of the utility model is a high-efficiency methanol water washing and demisting device, comprising an equipment body, characterized in that it also comprises an inlet assembly, a U-shaped absorption tower plate, a sealing plate, a coalescing membrane block washing assembly, a coalescing demisting module, a folding plate demister, and a downcomer;

[0006] The inlet assembly is located at the lower section of the equipment body, and includes an inlet pipe and a fin distributor. The fin distributor is connected to the inlet pipe and fixed to the inside of the equipment body through reinforcing ribs.

[0007] The U-shaped absorption tray is located above the inlet assembly and is fixed to the inside of the equipment body through the tray support ring and support beam. It is a floating valve tray;

[0008] The folded plate demister is located on the upper part of the U-shaped absorption tower tray, fixed to the equipment body and the sealing plate, installed vertically, and divides this section of the equipment into two along the central axis of the equipment body;

[0009] The sealing plate is welded to the inner wall of the tower body, and an inspection hole is opened on the sealing plate for easy maintenance;

[0010] The coalescing and demisting module is located on the upper part of the folding plate demisting device, fixed to the equipment body and the sealing plate, and installed vertically, dividing this section of the equipment into two parts along the central axis of the equipment body;

[0011] The coalescing membrane block flushing assembly is located in the center of the coalescing and demisting module, keeping a certain distance from the coalescing and demisting module, and is connected to the equipment body flange, and is detachable;

[0012] The bottom of the folded plate demister and the coalescing demister module are both provided with a liquid collecting tank, and a downcomer is installed below the liquid collecting tank. The downcomer is directly connected to the tower plate liquid receiving tray and maintains an appropriate distance from the tower plate liquid receiving tray.

[0013] After the methanol synthesis gas enters the fin distributor from the inlet pipe, it is evenly distributed through the fins evenly arranged in the fin distributor, flows out from both sides of the fin distributor, and rises evenly along the tower cross section; it passes through the U-shaped absorption tower plate in turn, and utilizes the infinite miscibility of water and methanol. After sufficient gas-liquid mixing, the methanol contained in the methanol synthesis gas is gradually transferred from bottom to top into the absorption liquid, and finally a methanol solution of more than 60% is obtained at the bottom of the tower. The washed methanol synthesis gas is then double-defogged by a folded plate demister and a coalescing demister membrane block, which efficiently removes the mist and foam entrainment in the synthesis gas and reduces the methanol content in the circulating gas.

[0014] Furthermore, the sealing plate welded at the bottom of the coalescence demisting module and the sealing plate welded at the bottom of the folding plate demister are installed in a staggered manner, forcing the methanol synthesis gas to flow through the folding plate demister and the coalescence demisting module.

[0015] Furthermore, the folded plate demister adopts a single-bag folded plate demister structure, and the folded plate is a multi-folded structure, thereby forming a tortuous gas channel.

[0016] Furthermore, the fins of the fin distributor form a certain angle with the radial direction of the cylinder of the equipment body.

[0017] Furthermore, the flushing direction of the coalescence membrane block flushing assembly is consistent with the gas flow direction.

[0018] Furthermore, the coalescence demisting module is woven from extremely fine fibers into a loose mesh structure with a large specific surface area.

[0019] The utility model of high-efficiency methanol water washing and demisting device has the following effects:

[0020] 1. The inlet assembly 2 includes an inlet pipe and a fin distributor, which is located in the lower section of the equipment body 1. After the methanol synthesis gas is evenly distributed through the fins evenly arranged in the fin distributor in the inlet assembly 2, it flows out from both sides of the fin distributor and rises evenly along the tower cross section.

[0021] 2. The U-shaped absorption tray 3 is located on the inlet component 2. The methanol synthesis gas evenly flows through the U-shaped absorption tray 3 after the fins are evenly distributed. By utilizing the infinite miscibility of water and methanol, the methanol is fully mixed and contacted with the absorption liquid. The methanol contained in the circulating gas is gradually transferred to the absorption liquid from bottom to top. When passing through the U-shaped absorption tray 3, the methanol concentration on the lower tray is higher, and finally a methanol solution with a concentration of more than 60% is obtained on the bottom tray, thereby reducing the methanol content in the circulating gas.

[0022] 3. The folded plate demister 8 is located on the upper part of the U-shaped absorption tray 3 and adopts a single-capsule folded plate demister structure. It has high capture efficiency for medium-sized and large-sized droplets and relatively low pressure drop. When the synthetic gas containing mist flows through the folded plate demister, due to the structural characteristics of the folded plate, the gas flow direction is changed many times. Under the action of inertia, the droplets contained in the gas continuously collide with the folded plate surface and are captured in the folded plate capsule. The multi-folded structure of the folded plate increases the chances of gas collision and mist capture. This repeated action greatly improves the demisting efficiency.

[0023] 4. The coalescence demisting module 7 is located on the upper part of the folded plate demister 8, at the top of the equipment body 1, and is woven from extremely fine fibers into a loose mesh structure with a relatively large specific surface area. The fine droplets in the synthetic gas after being defogged by the folded plate demister collide multiple times on its surface, condense and grow, thereby bringing extremely high separation efficiency, and finally obtaining clean circulating gas after purification.

[0024] 5. A flushing assembly 6 is installed directly in front of the coalescing and demisting module 7 for cleaning the high-efficiency coalescing and demisting module 7. The flushing direction is consistent with the gas flow direction to avoid secondary entrainment. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a structural schematic diagram of the utility model;

[0026] Explanation of the accompanying drawings: 1. Equipment body; 2. Inlet assembly; 3. U-shaped absorption tower plate; 4. Inspection hole; 5. Sealing plate; 6. Coalescence membrane block flushing assembly; 7. Coalescence demister module; 8. Folding plate demister; 9. Downcomer; 10. Tower plate liquid receiving tray; 11. Circulating gas outlet; 12. Fin distributor; 13. Liquid collecting tank. DETAILED DESCRIPTION

[0027] like Figure 1 As shown, a high-efficiency methanol water washing and demisting device, the equipment body 1 is composed of a tower, a head, a cylinder, a skirt and auxiliary pipe fittings.

[0028] The inlet assembly 2 includes an inlet pipe and a fin distributor 12, which is located in the lower section of the equipment body 1 and fixed to the equipment body 1. The fin distributor is located inside the equipment body, communicated with the inlet pipe, and fixed to the inside of the equipment body through reinforcing ribs.

[0029] The U-shaped absorption tray 3 is located above the inlet assembly 2 and is fixed to the inside of the equipment body through a tray support ring and a support beam. The tray is a floating valve tray.

[0030] The sealing plate 5 is welded to the inner wall of the tower body, and an inspection hole 4 is opened on the sealing plate 5 for easy inspection and maintenance.

[0031] The folded plate demister 8 is located on the upper part of the U-shaped absorption tower tray 3, fixed to the equipment body and the sealing plate 5, and installed vertically. It divides this section of the equipment into two parts along the central axis of the equipment body, and divides the space in the tower into two parts together with the sealing plate 5. After the sealing plate 5 staggers and blocks the gas channel, the synthesis gas A is forced to flow through the folded plate demister 8. A liquid collecting tank 13 is provided at the bottom of the folded plate demister 8, and a downcomer 9 is installed below the liquid collecting tank 13 to ensure that the liquid separated by the folded plate demister passes directly through the tower tray receiving tray 10 through the downcomer 9 to avoid secondary entrainment of the liquid.

[0032] The coalescing and demisting module 7 is located on the upper part of the folding plate demister 8, the uppermost end of the equipment body 1, fixed to the equipment body, and installed vertically. This section of the equipment is divided into two parts along the central axis of the equipment body. The gas channel is staggered and blocked by the sealing plate 5 to force the methanol synthesis gas to flow through the coalescing and demisting module 7. A liquid collecting tank 13 is provided at the bottom of the high-efficiency coalescing and demisting module 7, and a downcomer 9 is installed below the liquid collecting tank 13 to ensure that the liquid separated by the coalescing and demisting module 7 passes through the downcomer 9 directly to the tower plate receiving tray 10.

[0033] The coalescence membrane block flushing assembly 6 is located in the center of the coalescence and demisting module 7, and is kept at a distance from the coalescence and demisting module 7. It is flange-connected to the equipment body 1 and is removable.

[0034] The circulating gas outlet 11 is located at the top of the equipment body and is welded to the equipment body.

[0035] After the methanol synthesis gas enters the fin distributor 12 from the inlet pipe, it is evenly distributed by the fins evenly arranged in the fin distributor, flows out from both sides of the fin distributor, and rises evenly along the tower cross section; it passes through the U-shaped absorption tower plate 3 in turn, and utilizes the infinite miscibility of water and methanol. After sufficient gas-liquid mixing, the methanol contained in the methanol synthesis gas is gradually transferred from bottom to top into the absorption liquid, and finally a methanol solution of more than 60% is obtained at the bottom of the tower. The washed methanol synthesis gas is defogged by the folded plate coalescing and demisting 8 and the coalescing and demisting membrane block 7, and the mist entrainment in the synthesis gas is efficiently removed, thereby reducing the methanol content in the circulating gas.

Claims

1. A high-efficiency methanol water washing and demisting device, comprising a device body (1), characterized in that It also includes an inlet assembly (2), a U-shaped absorption tower plate (3), a sealing plate (5), a coalescence membrane block flushing assembly (6), a coalescence demisting module (7), a folded plate demister (8), and a downcomer (9); The inlet assembly (2) is located at the lower section of the equipment body (1), and comprises an inlet pipe and a fin distributor (12); the fin distributor (12) is connected to the inlet pipe and is fixed to the inside of the equipment body via reinforcing ribs; The U-shaped absorption tower tray (3) is located above the inlet assembly (2) and is fixed to the inside of the equipment body through a tower tray support ring and a support beam, and is a floating valve tower tray; The folded plate demister (8) is located on the upper part of the U-shaped absorption tower plate (3), fixed to the equipment body and the sealing plate (5), and installed vertically, dividing this section of the equipment into two along the central axis of the equipment body; The sealing plate (5) is welded to the inner wall of the tower body, and an inspection hole (4) is opened on the sealing plate (5); The coalescence demisting module (7) is located on the upper part of the folding plate demisting device (8), fixed to the equipment body and the sealing plate (5), and installed vertically, dividing this section of the equipment into two along the central axis of the equipment body; The coalescing membrane block flushing assembly (6) is located at the center of the coalescing demisting module (7), is kept at a distance from the coalescing demisting module (7), is flange-connected to the equipment body, and is detachable; A liquid collecting trough (13) is provided at the bottom of the folded plate demister (8) and the coalescence demister module (7), and a liquid downcomer (9) is installed below the liquid collecting trough (13). The liquid downcomer (9) directly passes through the tower plate liquid receiving tray (10) and maintains an appropriate distance from the tower plate liquid receiving tray (10).

2. A high-efficiency methanol water washing and demisting device as claimed in claim 1, characterized in that The sealing plate (5) welded at the bottom of the coalescence demisting module (7) and the sealing plate (5) welded at the bottom of the folding plate demisting device (8) are installed in a staggered manner, so that the methanol synthesis gas is forced to flow through the folding plate demisting device (8) and the coalescence demisting module (7).

3. A high-efficiency methanol water washing and demisting device as claimed in claim 1, characterized in that The folded plate demister (8) adopts a single-bag folded plate demister structure, and the folded plate is a multi-fold structure, thereby forming a tortuous gas passage.

4. A high-efficiency methanol water washing and demisting device as claimed in claim 1, characterized in that The fins of the fin distributor (12) form a certain angle with the radial direction of the cylinder of the equipment body.

5. A high-efficiency methanol water washing and demisting device as claimed in claim 1, characterized in that The flushing direction of the coalescence membrane block flushing assembly (6) is consistent with the gas flow direction.

6. A high-efficiency methanol water washing and demisting device as claimed in claim 1, characterized in that The coalescence demisting module (7) is made of extremely fine fibers woven into a loose mesh structure with a large specific surface area.

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