Inner cylinder drainage device of wet flue gas discharge chimney

Abstract

The invention discloses a wet flue gas emission chimney inner cylinder drainage device which comprises an inner cylinder inner wall fixed to a wet flue gas chimney and a plurality of water collecting ring-shaped discs arranged up and down at intervals, every two vertically adjacent water collecting ring-shaped discs are communicated through a drainage pipe, and a water retaining structure is arranged at the top of the inner cylinder. The drainage pipe arranged on the topmost water collecting annular disc extends upwards and is communicated with a barrel top water collecting tank formed between the water retaining structure and the outer wall of the inner barrel through an open hole formed in the top of the inner barrel, the barrel top water collecting tank is opened upwards and is communicated with the outside, and the diameter of the inner barrel is controlled, so that the diameter of the inner barrel is controlled to be larger than the diameter of the inner barrel. And the rising velocity of the wet flue gas does not exceed 16m / s. Condensate water generated in the process that wet flue gas is discharged through the inner barrel can be effectively collected and dredged to the bottom of the inner barrel, and chimney rain is avoided.

Description

Technical Field

[0001] The invention relates to a chimney drain device, in particular to an inner cylinder drain device designed for wet flue gas obtained by wet denitration treatment such as chlorine dioxide denitration in alkali furnaces and lime kilns in the pulp and paper industry. Background Art

[0002] In the pulp and paper industry, alkali furnaces and lime kilns are core production equipment. The flue gas generated by these equipment during operation contains a high concentration of nitrogen oxides, which exceeds environmental protection standards. Therefore, the flue gas must be denitrated. The conventional chlorine dioxide denitrification method is to spray the flue gas with chlorine dioxide in the denitrification tower before the flue gas is discharged, effectively converting nitrogen oxides into nitrates before discharging them through the chimney inner tube. However, from the actual implementation, it can be seen that the denitrification process will introduce moisture. The flue gas with moisture (wet flue gas) will condense on the inner wall of the inner tube during the discharge process through the inner tube, and condense when it meets the external cold air when it is discharged to the top of the inner tube, thereby forming "chimney rain". This "chimney rain" will cause corrosion to surrounding equipment and cause certain pollution to the surrounding environment, which needs to be solved. Summary of the invention

[0003] The object of the present invention is to provide a wet flue gas emission chimney inner tube drainage device, which can effectively collect and drain the condensed water generated in the process of wet flue gas being discharged through the inner tube to the bottom of the inner tube, thereby avoiding the formation of "chimney rain".

[0004] In order to achieve the above object, the present invention adopts the following technical solutions:

[0005] A wet flue gas emission chimney inner cylinder drain device comprises a plurality of water collecting annular plates fixed to the inner wall of the inner cylinder of the wet flue gas chimney and spaced apart from each other, two upper and lower adjacent water collecting annular plates being connected via a drain pipe, a water retaining structure being provided at the top of the inner cylinder, the drain pipe arranged on the uppermost water collecting annular plate extending upward and connected to a cylinder top water collecting trough formed between the water retaining structure and the outer wall of the inner cylinder via an opening provided at the top of the inner cylinder, the cylinder top water collecting trough being open upward and connected to the outside, wherein the rising velocity of the wet flue gas is controlled to be no more than 16 m / s by controlling the diameter of the inner cylinder.

[0006] The advantages of the present invention are:

[0007] The present invention can effectively collect and guide the condensed water generated when the wet flue gas encounters the inner wall of the inner cylinder during the process of rising through the inner cylinder, as well as the condensed water generated when the wet flue gas encounters the external cold air when discharged to the top of the inner cylinder, to the bottom of the inner cylinder, so that the moisture carried out of the outside of the inner cylinder is greatly reduced, thereby avoiding the formation of "chimney rain" and greatly reducing the corrosion to surrounding equipment and the pollution to the surrounding environment. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] Figure 1 It is a partial schematic diagram of the structure of the inner tube water drain device of the wet flue gas emission chimney of the present invention.

[0009] Figure 2 yes Figure 1 An enlarged schematic diagram of the AA section view.

[0010] Figure 3 yes Figure 2 A partial enlarged schematic diagram of the BB section view.

[0011] Figure 4 yes Figure 1 Schematic diagram of enlarged portion C.

[0012] Figure 5 It is a schematic diagram of the drain pipe at the connection position of the inner tube expansion joint. DETAILED DESCRIPTION

[0013] like Figures 1 to 5 The present invention proposes a wet flue gas emission chimney inner cylinder drain device, which is used for the inner cylinder 20 of the wet flue gas chimney, and includes a plurality of water collecting annular plates fixed to the inner wall of the inner cylinder 20 of the wet flue gas chimney and spaced apart from each other. Two upper and lower adjacent water collecting annular plates are connected by a drain pipe 31. A water retaining structure 34 is provided on the top of the inner cylinder 20. The drain pipe 31 arranged on the uppermost water collecting annular plate extends upward and is connected to the water retaining structure 34 and a cylinder top water collecting trough 40 formed between the outer wall of the inner cylinder 20 through an opening 21 opened on the top of the inner cylinder 20. The cylinder top water collecting trough 40 is open upward and communicated with the outside. By controlling the diameter of the inner cylinder 20, the rising flow velocity of the wet flue gas does not exceed 16 m / s, so as to better prevent the wet flue gas from being atomized under high-speed flow, and more effectively avoid the formation of "chimney rain".

[0014] In the pulp and paper industry, the wet flue gas chimney includes an outer cylinder 10, in which one or more inner cylinders 20 are arranged. Figure 1 The figure shows a situation where an inner cylinder 20 is arranged inside the outer cylinder 10. Generally, the outer cylinder 10 is made of stainless steel or glass fiber reinforced plastic, and the inner cylinder 20 is made of titanium composite plate.

[0015] In practical applications, a water collecting annular disk is usually arranged in the inner cylinder 20 at intervals of 15m. The design of multi-layer water collecting annular disks can effectively improve the water collection efficiency. Figures 1 to 3 To understand, the water collecting ring plate includes at least two water collecting boxes 32, and a water collecting ring 33 is connected between two adjacent water collecting boxes 32; a drain pipe 31 is provided between two upper and lower adjacent water collecting boxes 32, and the top pipe opening of the drain pipe 31 is connected to the bottom opening of the upper water collecting box 32 and the bottom pipe opening is opposite to the top opening of the lower water collecting box 32.

[0016] Furthermore, the water collecting boxes 32 of each water collecting annular plate are evenly distributed along the circumference of the inner cylinder 20. Figure 2 The figure shows a situation where the water collecting annular disk is designed with two water collecting boxes 32. The water collecting boxes 32 on each water collecting annular disk are arranged opposite to the water collecting boxes 32 on the upper and lower adjacent water collecting annular disks respectively. Correspondingly, the drain pipe 31 is arranged vertically and fixed to the inner wall of the inner tube 20 by the fixing member 35.

[0017] like Figure 3 The water collecting box 32 is fixed on the inner wall of the inner cylinder 20, the bottom of the plate-shaped water collecting ring 33 is fixed to the inner wall of the inner cylinder 20, the water collecting ring 33 is inclined with the inner wall of the inner cylinder 20 to form a water collecting ring groove 50, and the water collecting ring groove 50 is connected with the water collecting cavity of the water collecting box 32. Preferably, as Figure 3 The water collecting box 32 is small at the top and large at the bottom, and is in the shape of a truncated cone, which is certainly not limited.

[0018] like Figure 3 The upper part of the water collecting ring 33 is provided with a plurality of long slits 330, and the long slits 330 are arranged obliquely relative to the upper and lower sides of the water collecting ring 33. For example, the long slits 330 are parallel, and the inclination angle of the long slits 330 is designed to be 60°. The function of the long slits 330 is to collect the condensed water generated by the rising wet flue gas meeting the inner wall of the inner cylinder 20 while the water collecting ring 33 does not hinder the smooth rising flow and discharge of the wet flue gas.

[0019] Usually, the bottom opening of the water collecting box 32 of the lowest water collecting annular plate is connected to a drain pipe 31 , and the bottom pipe opening of the drain pipe 31 extends to the bottom of the inner cylinder 20 .

[0020] like Figure 4 The water retaining structure 34 includes a circle of water retaining plates 341 fixed on the outer wall of the top of the inner tube 20, the bottom of the water retaining plate 341 is fixed to the outer wall of the inner tube 20, the top water collecting trough 40 formed between the water retaining plate 341 and the outer wall of the inner tube 20 is connected to the opening 21, and the drain pipe 31 at the top in the inner tube 20 is connected to the opening 21 via the elbow pipe 310.

[0021] In actual design, the shape of the water retaining plate 341 is not limited and can be various. Figure 4 The cross section of the water retaining plate 341 is shown to be obtuse-angled.

[0022] Furthermore, if Figure 4 The top of the water baffle 341 is upward and exceeds the top of the inner cylinder 20, and the top of the water baffle 341 is connected to the top of the inner cylinder 20 through a connecting piece 342, wherein: the number of connecting pieces 342 is multiple and arranged at intervals to facilitate the connection between the cylinder top water collection tank 40 and the outside, thereby increasing the stability of the water baffle 341 and improving the condensed water collection efficiency. Figure 4The connecting member 342 shown is a connecting member with a C-shaped cross section, but it can also be designed with a cross section of other shapes without limitation.

[0023] like Figure 5 The drain pipe 31 at the expansion joint connection position of the inner cylinder 20 is formed by a thin pipe 311 and a thick pipe 312 plugged in from top to bottom, so as to prevent the drain pipe 31 here from being damaged by the expansion of the inner cylinder 20. In actual design, the thin pipe 311 is designed to be DN80 (nominal diameter 80 mm) and the thick pipe 312 is designed to be DN100 (nominal diameter 100 mm).

[0024] In actual design, the water collecting box 32, the water collecting ring 33, the drain pipe 31, etc. should be made of high temperature resistant and corrosion resistant alloy steel.

[0025] When in use, the wet flue gas produced after denitration treatment rises through the bottom of the inner cylinder 20 (such as Figure 1 As shown by the solid arrow, during the rising process, the wet flue gas will form condensed water when it meets the inner wall of the inner cylinder 20, so the condensed water flows down along the inner wall of the inner cylinder 20 to the water collecting ring 33 and the inner wall of the inner cylinder 20. The water then flows into the water collecting cavity of the water collecting box 32, and then flows into the drain pipe 31 connected below the water collecting box 32, and is then drained downward from top to bottom through the water collecting boxes 32 of each water collecting annular disk to the bottom of the inner cylinder 20. Therefore, during the rising process of the wet flue gas, most of the water in it has been collected by each water collecting annular disk, and the remaining small amount of water will generate condensed water when the wet flue gas is discharged to the top of the inner cylinder 20 because it meets the external cold air. This condensed water falls into the cylinder top water collecting groove 40 formed by the water baffle 341 and the outer wall of the inner cylinder 20, and then enters the drain pipe 31 through the opening 21 and the elbow pipe 310 (as shown in FIG. Figure 4 As shown by the dotted arrow, the water is drained downward from top to bottom through the water collecting boxes 32 of each water collecting annular disk to the bottom of the inner tube 20. It can be seen that through the design of the present invention, the moisture in the flue gas to be discharged to the outside has been basically effectively collected and drained to the bottom of the inner tube, thereby effectively avoiding the formation of "chimney rain" and greatly reducing the corrosion to surrounding equipment and the pollution to the surrounding environment.

[0026] The advantages of the present invention are:

[0027] The present invention is designed for wet flue gas obtained by wet denitrification treatment such as chlorine dioxide denitrification in alkali furnaces and lime kilns in the pulp and paper industry. The present invention can effectively collect and guide the condensed water generated by the wet flue gas encountering the inner wall of the inner tube when it rises through the inner tube, as well as the condensed water generated by the wet flue gas encountering the external cold air when it is discharged to the top of the inner tube, to the bottom of the inner tube, so that the moisture carried out of the outside of the inner tube is greatly reduced, thereby avoiding the formation of "chimney rain" and greatly reducing the corrosion to surrounding equipment and the pollution to the surrounding environment.

[0028] The above are preferred embodiments of the present invention and the technical principles used therein. For those skilled in the art, any obvious changes such as equivalent transformations, simple replacements, etc. based on the technical solution of the present invention, without departing from the spirit and scope of the present invention, are within the scope of protection of the present invention.

Claims

1. A wet flue gas discharge chimney inner tube drain device, characterized in that: It comprises an inner wall of an inner cylinder fixed to a wet flue gas chimney and a plurality of water collecting annular plates spaced apart from each other in upper and lower parts, two adjacent water collecting annular plates being connected via a drain pipe, a water retaining structure being provided on the top of the inner cylinder, the drain pipe arranged on the uppermost water collecting annular plate extending upward and being connected to a cylinder top water collecting trough formed between the water retaining structure and the outer wall of the inner cylinder through an opening provided on the top of the inner cylinder, the cylinder top water collecting trough being open upward and connected to the outside, wherein the rising velocity of the wet flue gas is controlled to be no more than 16 m / s by controlling the diameter of the inner cylinder.

2. The wet flue gas discharge chimney inner tube drain device according to claim 1, characterized in that: The water collecting ring plate includes at least two water collecting boxes, and a water collecting ring is connected between two adjacent water collecting boxes; the drain pipe is arranged between two upper and lower adjacent water collecting boxes, and the top pipe opening of the drain pipe is connected to the bottom opening of the upper water collecting box and the bottom pipe opening is opposite to the top opening of the lower water collecting box.

3. The wet flue gas discharge chimney inner barrel drain device according to claim 2, characterized in that: The water collecting boxes of each water collecting annular disk are evenly distributed along the circumferential direction of the inner cylinder, and the water collecting boxes on each water collecting annular disk are respectively arranged opposite to each other up and down and up and down and the water collecting boxes on the water collecting annular disks adjacent to each other up and down, and the drain pipe is vertically arranged and fixed to the inner wall of the inner cylinder through a fixing piece.

4. The wet flue gas discharge chimney inner barrel drain device according to claim 2, characterized in that: The water collecting box is fixed on the inner wall of the inner cylinder, the bottom of the plate-shaped water collecting ring is fixed to the inner wall of the inner cylinder, the water collecting ring is inclined with the inner wall of the inner cylinder to form a water collecting ring groove, and the water collecting ring groove is connected with the water collecting cavity of the water collecting box.

5. The wet flue gas discharge chimney inner tube drain device according to claim 4, characterized in that: A plurality of long slits are arranged on the upper part of the water collecting ring, and the long slits are arranged obliquely relative to the upper and lower sides of the water collecting ring.

6. The wet flue gas discharge chimney inner barrel drain device according to claim 2, characterized in that: The bottom opening of the water collecting box of the water collecting annular plate at the bottom is connected with a drain pipe, and the bottom pipe opening of the drain pipe extends to the bottom of the inner cylinder.

7. The wet flue gas discharge chimney inner tube drain device according to claim 1, characterized in that: The water retaining structure includes a circle of water retaining plates fixed on the outer wall of the top of the inner cylinder, the bottom of the water retaining plates is fixed to the outer wall of the inner cylinder, the top water collecting trough formed between the water retaining plates and the outer wall of the inner cylinder is connected to the opening, and the drain pipe at the top of the inner cylinder is connected to the opening via an elbow pipe.

8. The wet flue gas discharge chimney inner barrel drain device according to claim 7, characterized in that: The top of the water baffle plate is upward and exceeds the top of the inner tube, and the top of the water baffle plate is connected to the top of the inner tube through a connecting piece, wherein: the number of the connecting pieces is multiple and they are arranged at intervals.

9. The wet flue gas discharge chimney inner barrel drain device according to claim 1, characterized in that: The drain pipe at the expansion joint connection position of the inner tube is formed by a thin pipe and a thick pipe plugged in up and down.

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