Absorption tower

Abstract

The invention provides an absorption tower. The absorption tower comprises an absorption tower main body, the stirring end of the stirring shaft is used for penetrating through the wall of the absorption tower main body and then extending towards the inner cavity of the absorption tower main body; the first end of the water sealing sleeve is used for being connected with the wall of the absorption tower body, the second end of the water sealing sleeve extends towards the stirring end of the stirring shaft relative to the first end, and the water sealing sleeve is located in an inner cavity of the absorption tower body and connected to the outer wall of the stirring shaft in a sleeving mode so that a cavity can be formed by the water sealing sleeve and the wall of the absorption tower body. The water sealing sleeve can effectively isolate desulfurization slurry in the inner cavity of the absorption tower body outside the mechanical seal, provides a good operation medium environment for the mechanical seal, and provides a fulcrum for the stirring shaft, so that the radial stress of the stirring shaft can be greatly reduced, and the bending fault of the stirring shaft can be effectively eliminated or reduced.

Description

Technical Field

[0001] The present invention belongs to the technical field of harmful object treatment, and particularly relates to an absorption tower. Background Art

[0002] An absorption tower is a device widely used in multiple industries, mainly used to treat harmful substances in gases or liquids to achieve absorption operations.

[0003] For example, in the wet flue gas desulfurization system of a thermal power plant, the main function of the absorption tower is to remove sulfur dioxide in the flue gas, reduce the sulfur content in the flue gas emissions, and meet environmental protection requirements. Structurally, a side-entry mixer is provided on the absorption tower to prevent the deposition of solid-containing slurry and promote the oxidation of by-product calcium sulfite in desulfurization. However, the side-entry mixer seriously affects reliable operation due to problems such as the bending of the mixing shaft and resulting mechanical seal leakage. Specifically, the side-entry mixer has a cantilever structure. In the absorption tower, the support bearings, thrust bearings, and mechanical seal bearings in the reducer are the fulcrums of the entire mixer's shaft system. The disadvantage of this structure is that the mixing shaft is prone to bending at the mechanical seal bearing position. The weight of the impeller at the cantilever end of the mixing shaft (the impeller weight of a mixer manufactured by German MUT with a power of 55KW is 210kg) and the reaction force of the fluid on the impeller during operation are also likely to cause the mixing shaft to bend. After such a problem occurs, the operation trajectory of the impeller begins to deviate from the axis of the mixing shaft, and the mixing shaft operates eccentrically, resulting in an increase in equipment vibration. Moreover, due to the increase in the deflection of the mixing shaft, the static and dynamic rings of the mechanical seal deviate from the axis of rotation, and coupled with the increase in vibration, the mechanical seal begins to experience slurry leakage failure.

[0004] In the above situation, only the mixing shaft and mechanical seal can be replaced after the desulfurization system is shut down. During each overhaul of the desulfurization system, the inspection of the bending of the mixing shaft of this type of equipment is listed as a standard inspection item, and as long as this type of shaft has undergone bending deformation, even after being corrected and reinstalled for use, the same problem will occur again after a short period of use. The slurry medium in the desulfurization absorption tower, such as a mixture of calcium sulfate and calcium sulfite, is insoluble in water. Under the agitation of the mixer, slurry deposition will occur in the dead corners of the absorption tower, such as the seal bowl area of the absorption tower. When deposition occurs in this area, the mechanical seal of the mixer relies on the water in the medium to achieve the self-lubrication and cooling functions of the static and dynamic rings. If the slurry density in the contact medium area increases or even the mechanical seal is buried in solids, its self-lubrication and cooling functions fail, and the mechanical seal will experience leakage failure, and only after the system is shut down to clean the deposits near the seal bowl can the mechanical seal be replaced.

[0005] Therefore, it is necessary to design an absorption tower to reduce the bending of the mixing shaft of the mixer and reduce the slurry deposition in the dead corners of the absorption tower. Summary of the Invention

[0006] In view of some or all of the above technical problems existing in the prior art, the present invention provides an absorption tower. In this absorption tower, the inner cavity of the absorption tower body, such as desulfurization slurry, can be effectively isolated outside the mechanical seal, providing a good operating medium environment for the mechanical seal. At the same time, it also provides a fulcrum for the stirring shaft, which can greatly reduce the radial force on the stirring shaft and effectively eliminate or reduce the bending failure of the stirring shaft.

[0007] According to the present invention, there is provided an absorption tower, comprising:

[0008] An absorption tower main body,

[0009] A stirring shaft, the stirring end of the stirring shaft is used to extend into the inner cavity of the absorption tower main body after passing through the wall of the absorption tower main body,

[0010] A water seal sleeve, the first end of the water seal sleeve is used to be connected to the wall of the absorption tower main body, the second end of the water seal sleeve extends towards the stirring end of the stirring shaft relative to the first end, the water seal sleeve is located in the inner cavity of the absorption tower main body and is sleeved on the outer wall of the stirring shaft to form a chamber with the wall of the absorption tower main body.

[0011] In one embodiment, the water seal sleeve includes:

[0012] A water seal sleeve main body, the water seal sleeve main body is configured as a cylinder and is sleeved on the outer wall of the stirring shaft at intervals, and the first end of the water seal sleeve is connected to the wall of the absorption tower main body,

[0013] A first ring, the outer wall of the first ring is fixedly arranged on the water seal sleeve and the inner wall extends towards the stirring shaft.

[0014] In one embodiment, a support disk is arranged on the wall of the absorption tower main body, a first connection flange is arranged at the first end of the water seal sleeve, and the water seal sleeve is connected to the support disk through the first connection flange.

[0015] In one embodiment, an inlet for selectively communicating with the chamber is arranged on the wall of the absorption tower main body, and an outlet for selectively communicating with the chamber is arranged on the wall of the absorption tower main body.

[0016] In one embodiment, the inlet communicates with incoming liquid, and the pressure of the incoming liquid is 0.2 - 0.3 MPa higher than the pressure of the slurry in the inner cavity of the absorption tower main body.

[0017] In one embodiment, the flow area of the outlet is 0.5 - 0.8 times that of the inlet.

[0018] In one embodiment, a sliding bushing seat is provided at the second end of the water seal sleeve. The sliding bushing seat body of the sliding bushing seat is spaced from the stirring shaft, and a sliding bushing is provided in a filling manner between the sliding bushing seat body and the stirring shaft.

[0019] In one embodiment, the sliding bushing is made of a polytetrafluoroethylene material filled with graphite.

[0020] In one embodiment, a bushing is fixedly sleeved on the outer wall of the stirring shaft, and the bushing is opposite to the sliding bushing in position.

[0021] In one embodiment, a locking ring is provided on the bushing. The locking ring is sleeved on the second end of the bushing, and a locking screw sequentially passes through the locking ring and the bushing and then connects to the stirring shaft.

[0022] Compared with the prior art, the advantages of the present invention are as follows: By sleeving a water seal sleeve on the stirring shaft, a chamber is formed between the water seal sleeve and the wall of the absorption tower main body, so as to isolate the medium in the absorption tower main body from the mechanical seal, providing a good operating medium environment for the mechanical seal. At the same time, the second end of the water seal sleeve has a continuous gap with the stirring shaft, which can limit the large bending of the stirring shaft and effectively reduce the bending failure of the stirring shaft. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings. In the drawings:

[0024] Figure 1 Shows a part of an absorption tower according to an embodiment of the present invention;

[0025] Figure 2 Is Figure 1 An enlarged view of part A;

[0026] Figure 3 Shows a water seal sleeve according to an embodiment of the present invention.

[0027] In the drawings, the same components are denoted by the same reference numerals. The drawings are not drawn to actual scale. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0028] In order to make the technical solutions and advantages of the present invention clearer, the exemplary embodiments of the present invention will be further described in detail below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than an exhaustive list of all embodiments. And without conflict, the embodiments in the present invention and the features in the embodiments can be combined with each other.

[0029] In the prior art, such as Figure 1As shown, the absorption tower includes an absorption tower main body 100. The absorption tower main body 100 is the main part of the absorption tower, and its inner cavity is mainly used to accommodate the medium. Taking the absorption tower applied to the wet flue gas desulfurization system of a thermal power plant as an example, the absorption tower main body 100 may contain a mixture of calcium sulfate and calcium sulfite. The absorption tower also includes a stirrer 200 arranged on the absorption tower main body 100. The stirrer 200 is a side-entry type. Structurally, a connecting convex groove 110 is arranged on the absorption tower main body 100. A stirring support 300 is arranged outside the connecting convex groove 110. The stirrer 200 is arranged on the absorption tower main body 100 through the stirrer support 300. In addition, the stirrer 200 includes a stirring shaft 210. The driving end of the stirring shaft 210 is connected to a driving source (the driving source is not shown in the figure and can be, for example, a motor) through a speed reducer 220. A support bearing 221 and a thrust bearing 222 are arranged in the speed reducer 220 for connecting the stirring shaft 210. The end of the stirring shaft 210 opposite to the driving end is the stirring end, and this stirring end extends into the inner cavity of the absorption tower main body 100 after passing through the wall at the connecting convex groove 110 of the absorption tower main body 100. An impeller 230 is arranged at the stirring end of the stirring shaft 210. During the rotation of the stirring shaft 210, the impeller 230 is driven to rotate to stir the medium in the inner cavity of the absorption tower main body 100. Moreover, a mechanical seal 240 is arranged between the absorption tower main body 100 and the stirring shaft 210 to play a sealing role and prevent the medium from flowing out of the inner cavity of the absorption tower main body 100. A sealing bowl 250 is also arranged on the stirring shaft 210. The sealing bowl 250 is constructed in a basin shape, the bottom wall of the sealing bowl 250 is sleeved on the stirring shaft 210, and the basin edge extends towards the driving end of the stirring shaft 210. The sealing bowl 250 is located in the inner cavity of the absorption tower main body 100. With this existing arrangement, the stirring shaft 210 is prone to bending deformation, and the mechanical seal 240 is prone to failure.

[0030] Therefore, according to the present application, as Figures 1 to 3 shown, a water seal sleeve 260 is additionally provided on the stirring shaft 210. The first end of the water seal sleeve 260 (consistent with the right end direction in Figure 1 is used to be connected to the wall of the absorption tower main body 100. The second end of the water seal sleeve 260 (consistent with Figure 1extends towards the stirring end of the stirring shaft 210 relative to the first end in the same direction as the left end in []. The stirring shaft 210 passes through the water seal sleeve 260 in an intermittent manner. The water seal sleeve 260 is located in the inner cavity of the absorption tower main body 100 and forms a chamber 270 with the wall of the absorption tower main body 100. It can be seen that by setting the water seal sleeve 260, a shielding effect can be achieved, effectively isolating the desulfurization slurry in the absorption tower main body 100 outside the mechanical seal 240, providing a good operating medium environment for the mechanical seal 240, and ensuring the service life of the mechanical seal 240. In addition, by adjusting the clearance fit between the water seal sleeve 260 and the stirring shaft 210, the water seal sleeve 260 can play a role in supporting and restricting the stirring shaft 210 to prevent the stirring shaft 210 from bending.

[0031] More specifically, a support disc 280 is provided on the absorption tower main body 100. The support disc 280 is fixed in the groove of the connecting convex groove 110, and its outer wall abuts against the inner groove wall of the connecting convex groove 110. The support disc 280 is preferably made of materials such as 316L, 2205, 2507, etc. that can withstand the corrosion of the slurry in the desulfurization absorption tower. The support disc 280 itself is a disc structure. The outer diameter of the support disc 280 is similar to the inner diameter D1 at the connecting convex groove 110. For example, the support disc 280 can be fixed to the inner diameter at the connecting convex groove 110 by welding. The welded part of the support disc 280 and the absorption tower main body 100 needs to be subjected to anti-corrosion treatment. The perpendicularity error between the welded support disc 280 and the stirring shaft 210 is less than 0.05 mm. The coaxiality error between the inner circle and the outer circle of the support disc 280 and the stirring shaft 210 is less than 0.05 mm. The support disc 280 is the key to ensuring the basic strength, and helps to maintain the levelness of the stirring shaft 210 and the concentricity with, for example, the water seal sleeve 260.

[0032] Structurally, the water seal sleeve 260 includes a water seal sleeve main body 261 and a first ring 262. The water seal sleeve main body 261 is configured as a cylinder and is sleeved on the outer wall of the stirring shaft 210 at intervals. The first end of the water seal sleeve main body 261 is connected to the wall of the absorption tower main body 100. It is easy to understand that the water seal sleeve main body 261 can be a cylindrical shape, a square tube shape, an oval tube shape, or a conical tube shape. In this application, an embodiment in which the water seal sleeve main body 261 is configured as a cylinder is given. The first ring 262 is fixedly arranged at the second end of the water seal sleeve main body 261 and extends towards the stirring shaft 210 to be connected to the stirring shaft 210 in an intermittent manner. For example, the outer wall of the first ring 262 is used to connect to the water seal sleeve main body 261, and the inner diameter D4 wall is 20 - 30 mm larger than the outer diameter D3 of the sliding shaft sleeve 294 (described later). It can be seen that by setting the first ring 262, the distance between the water seal sleeve 260 and the stirring shaft 210 is reduced, ensuring the isolation effect of the water seal sleeve 260.

[0033] In addition, the water seal sleeve 260 further includes a first connecting flange 263. The first connecting flange 263 is used to connect the water seal sleeve 260 to the support disk 280. As Figure 3 shown, the cross-section of the water seal sleeve 260 is configured in a "ji" character shape. The material of the water seal sleeve 260 is the same as that of the support disk 280. This setting can reduce the manufacturing cost and facilitate the connection.

[0034] The coaxiality error between the inner diameter of the first ring 262 of the water seal sleeve 260, the inner diameter of the first connecting flange 263 and the stirring shaft 210 is less than 0.05 mm, and the perpendicularity error between the first ring 262, the first connecting flange 263 of the water seal sleeve 260 and the stirring shaft 210 is less than 0.05 mm.

[0035] An inlet 120 and an outlet 130 are provided on the wall of the absorption tower main body 100. The inlet 120 is used to selectively communicate with the chamber 270. Through the inlet 120, an external liquid source can be connected to inject a fluid, such as water, into the chamber 270. The outlet 130 is used to selectively communicate with the chamber 270 to discharge the medium in the chamber 270 into the inner cavity of the absorption tower main body 100.

[0036] Specifically, the inlet 120 is provided on the upper groove wall of the connecting convex groove 110. For example, the inner diameter of the inlet 120 is not less than φ25 mm. A shut-off valve capable of cutting off the incoming liquid should be installed upstream of the inlet 120. The inlet 120 is connected to the incoming liquid. The pressure of the incoming liquid is 0.2 - 0.3 MPa higher than the pressure of the slurry in the inner cavity of the absorption tower main body 100. The outlet 130 is provided on the lower groove wall of the connecting convex groove 110. The flow-through area of the outlet 130 is 0.5 - 0.8 of the flow-through area of the inlet 120. For example, the inner diameter of the outlet 130 is not greater than φ20 mm. A shut-off valve capable of cutting off should be installed downstream of the outlet 130.

[0037] By providing the inlet 120 and the outlet 130, water can be injected into the chamber 270 and the medium can be discharged. Since the hydraulic pressure in the chamber 270 is higher than the slurry pressure in the inner cavity of the absorption tower main body 100, the water jets from the second end of the water seal sleeve 260 into the inner cavity of the absorption tower main body 100, isolating the desulfurization slurry outside the mechanical seal 240 through the chamber 270, providing a good operating medium environment for the mechanical seal 240, and ensuring the service life of the mechanical seal 240. In addition, the outlet 130 can also perform sewage discharge operations to ensure long-term stable operation. The flow-through area of the outlet 130 is smaller than that of the inlet 120. Even if the outlet 130 and the inlet 120 are always open, there is still water in the chamber 270, which can achieve the purpose of isolating the desulfurization slurry. It can be seen that by providing the inlet 120 and the outlet 130, water can be injected into the chamber 270, improving the isolation effect, effectively preventing the desulfurization slurry in the absorption tower main body 100 from approaching the seal bowl 250 and the mechanical seal 240, and ensuring the normal operation of the mechanical seal 240.

[0038] A sliding bushing seat 290 is provided at the second end of the water seal sleeve 260. Specifically, the sliding bushing seat 290 includes a sliding bushing seat body 291, a second circular ring 293, and a second connecting flange 293. Among them, the sliding bushing seat body 291 is cylindrical and is sleeved on the outer wall of the stirring shaft 210 at intervals. The second circular ring 293 is provided at the second end of the sliding bushing seat body 291 and is configured as a disc-shaped ring extending from the sliding bushing seat body 291 towards the stirring shaft 210. The second connecting flange 293 is provided at the first end of the sliding bushing seat body 291 and is used to connect to the first circular ring 262, such as screw connection. That is to say, the sliding bushing seat 290 is also configured as a structure with a generally "J" shaped cross-section. The material of the sliding bushing seat 290 is the same as that of the water seal sleeve 260. The coaxiality error between the inner diameter of the second circular ring 293 and the inner diameter of the second connecting flange 293 and the stirring shaft is less than 0.05 mm. The perpendicularity error between the second circular ring 293 and the second connecting flange 293 and the stirring shaft 210 is less than 0.05 mm.

[0039] A sliding bushing 294 is filled and provided between the sliding bushing seat body 291 of the sliding bushing seat 290 and the stirring shaft 210. The sliding bushing 294 can be connected to the sliding bushing seat body 291 through anti-rotation screws. The sliding bushing 294 is made of polytetrafluoroethylene material filled with graphite. After the stirring shaft 210 receives a radial external force, the self-lubricity of the sliding bushing 294 can effectively eliminate contact wear. It can be seen that by adding the sliding bushing 294 to the water seal sleeve 260, it can better cooperate and connect with the stirring shaft 210, ensuring the fulcrum effect on the stirring shaft 210.

[0040] A bushing 211 is fixedly sleeved on the outer wall of the stirring shaft 210. A locking ring 212 is provided on the bushing 211. The locking ring 212 is sleeved on the second end of the bushing 211. The locking screw 213 passes through the locking ring 212 and the bushing 211 in sequence and then connects to the stirring shaft 210. The bushing 211 is opposite to the sliding bushing 294 in position. The inner diameter of the sliding bushing 294 is 0.3 - 0.5 mm larger than the outer diameter of the bushing 211. The materials of the bushing 211 and the locking sleeve 212 are the same as the material of the water seal sleeve 260. The fit tolerance between the bushing 211 and the stirring shaft 210 is selected as H7, and the wall thickness is not less than 5 mm. The fit tolerance between the locking sleeve 212 and the bushing 211 is selected as F8. By adding the bushing 211, the direct contact between the stirring shaft 210 and the sliding bushing 294 can be avoided, effectively protecting the stirring shaft 210.

[0041] The method of installing a mixer on the absorption tower will be described in detail below with reference to the drawings.

[0042] Before reinstalling the impeller 230, insert the water seal sleeve 260 through the impeller 230 side into the stirring shaft 210. Connect the water seal sleeve 260 and the support disc 280 with connecting bolts (the connecting bolts at this place are temporarily not tightened). Install the positioning pin shaft between the water seal sleeve 260 and the support disc 280, and then tighten the connecting bolts between the water seal sleeve 260 and the support disc 280.

[0043] Install the shaft sleeve 211 from the impeller 230 side. The axial installation position of the first end of the shaft sleeve 211 exceeds the first ring 262 of the water seal sleeve 260.

[0044] Insert the sliding shaft sleeve 294 into the sliding shaft sleeve seat 290, and fix the sliding shaft sleeve 294 in the sliding shaft sleeve seat 290 with, for example, anti-rotation screws.

[0045] Insert the sliding shaft sleeve seat 290 equipped with the sliding shaft sleeve 294 from the impeller side, and connect the second connecting flange 293 of the sliding shaft sleeve seat 290 and the first ring 262 of the water seal sleeve 260 with connecting bolts (the connecting bolts at this place are temporarily not tightened). Install the positioning pin shaft between the first ring 262 and the second connecting flange 293, and then tighten the connecting bolts between the second connecting flange 293 and the first ring 262.

[0046] Install the locking ring 212 on the shaft sleeve 211, and then lock the shaft sleeve 211 on the stirring shaft 210 with the locking screw 213.

[0047] Install the impeller 230 on the stirring shaft 210.

[0048] Install the pipelines at the inlet 120 and the outlet 130.

[0049] In this application, before starting the absorption tower, close the outlet 130, start the inlet 120, and inject liquid, such as water, into the chamber 270. Since the flow area of the inlet 120 is much larger than the flow channel cross-section of the sliding shaft sleeve 294 and the shaft sleeve 211, the water pressure in the chamber 270 is higher than the slurry pressure in the absorption tower main body 100. Thus, the water in the chamber 270 sprays into the inner cavity of the absorption tower main body 100 through the gap between the sliding shaft sleeve 294 and the shaft sleeve 211, isolating the slurry in the absorption tower main body 100 outside the mechanical seal 240 and providing a good operating medium environment for the mechanical seal 240; the water pressure in the chamber 270 also provides good lubrication and cooling media for the sliding shaft sleeve 294 and the shaft sleeve 211, preventing the contact wear of the sliding shaft sleeve 294. A sliding shaft sleeve 294 is added on the load side of the stirring shaft 210 to support the stirring shaft 210, forming a similar fulcrum support, greatly reducing the radial force on the stirring shaft 210 and effectively eliminating the bending fault of the stirring shaft 210.

[0050] Although the preferred embodiments of the present invention have been described, additional changes and modifications can be made by those skilled in the art once they learn the basic creative concept. Therefore, the appended claims are intended to be interpreted to include the preferred embodiments as well as all changes and / or modifications that fall within the scope of the present invention. Any changes and / or modifications made in accordance with the embodiments of the present invention should be covered by the protection scope of the present invention.

Claims

1. An absorption tower, characterized in that, Comprising: Absorption tower main body, Stirring shaft, the stirring end of the stirring shaft is used to extend into the inner cavity of the absorption tower main body after passing through the wall of the absorption tower main body, Water seal sleeve, the first end of the water seal sleeve is used to connect with the wall of the absorption tower main body, the second end of the water seal sleeve extends towards the stirring end of the stirring shaft relative to the first end, the water seal sleeve is located in the inner cavity of the absorption tower main body and is sleeved on the outer wall of the stirring shaft to form a chamber with the wall of the absorption tower main body.

2. The absorption tower according to claim 1, characterized in that, The water seal sleeve includes: Water seal sleeve main body, the water seal sleeve main body is constructed as a cylinder and is sleeved on the outer wall of the stirring shaft at intervals, the first end of the water seal sleeve is connected with the wall of the absorption tower main body, First ring, the outer wall of the first ring is fixedly arranged on the water seal sleeve and the inner wall extends towards the stirring shaft.

3. The absorption tower according to claim 2, characterized in that, A support disk is arranged on the wall of the absorption tower main body, a first connection flange is arranged at the first end of the water seal sleeve, and the water seal sleeve is connected to the support disk through the first connection flange.

4. The absorption tower according to any one of claims 1 to 3, characterized in that, An inlet for selectively communicating with the chamber is arranged on the wall of the absorption tower main body, and an outlet for selectively communicating with the chamber is arranged on the wall of the absorption tower main body.

5. The absorption tower according to claim 4, characterized in that, The inlet is connected to the incoming liquid, and the pressure of the incoming liquid is 0.2 - 0.3 MPa higher than the pressure of the slurry in the inner cavity of the absorption tower main body.

6. The absorption tower according to claim 4 or 5, characterized in that, The flow area of the outlet is 0.5 - 0.8 of the flow area of the inlet.

7. The absorption tower according to any one of claims 1 to 6, characterized in that, A sliding shaft sleeve seat is arranged at the second end of the water seal sleeve, the sliding shaft sleeve seat main body of the sliding shaft sleeve seat is spaced from the stirring shaft, and a sliding shaft sleeve is arranged in a filling manner between the sliding shaft sleeve seat main body and the stirring shaft.

8. The absorption tower according to claim 7, characterized in that, The sliding shaft sleeve is made of a polytetrafluoroethylene material filled with graphite.

9. The absorption tower according to claim 7 or 8, characterized in that, A shaft sleeve is fixedly sleeved on the outer wall of the stirring shaft, and the shaft sleeve is opposite to the sliding shaft sleeve in position.

10. The absorption tower according to claim 9, characterized in that, A locking ring is arranged on the shaft sleeve, the locking ring is sleeved on the second end of the shaft sleeve, and the locking screw sequentially passes through the locking ring and the shaft sleeve and then connects the stirring shaft.

Images