阅读说明：本技术 一种scr脱硝装置的烟气流速调整结构 (SCR denitrification facility's flue gas velocity of flow adjustment structure ) 是由 徐晓涛 杨世极 舒凯 李淑宏 尚桐 袁壮 于 2021-07-20 设计创作，主要内容包括：本发明提供一种SCR脱硝装置的烟气流速调整结构,目的是降低脱硝出口的烟气流速偏差,均匀出口烟气流速,包括第一组导流板,第二组导流板,第三组导流板和一组均流板；SCR脱硝烟道包括第一转角烟道,第一直管烟道,第二转角烟道,第三转角烟道,第三直管烟道和第四转角烟道；第一组导流板设置在第四转角烟道内；第二组导流板设置在第二转角烟道内；第三组导流板包括引流部分和导流部分,沿第四转角烟道的高度方向呈间隔均匀设置；引流部分与第四转角烟道的上下表面平行,导流部分与连接烟道的对角面平行；一组均流板包括多个均流板,沿低温省煤器的进气端长度方向呈间隔设置,均流板垂直连接烟道的出气端,并与第四转角烟道横截面平行。(The invention provides a flue gas flow velocity adjusting structure of an SCR (selective catalytic reduction) denitration device, which aims to reduce flue gas flow velocity deviation of a denitration outlet and homogenize the flow velocity of outlet flue gas and comprises a first group of guide plates, a second group of guide plates, a third group of guide plates and a group of flow equalizing plates; the SCR denitration flue comprises a first corner flue, a first straight pipe flue, a second corner flue, a third straight pipe flue and a fourth corner flue; the first group of guide plates are arranged in the fourth corner flue; the second group of guide plates are arranged in the second corner flue; the third group of guide plates comprise a flow guiding part and a flow guiding part, and are uniformly arranged at intervals along the height direction of the fourth corner flue; the flow guide part is parallel to the upper surface and the lower surface of the fourth corner flue, and the flow guide part is parallel to the diagonal surface of the connecting flue; the group of flow equalizing plates comprise a plurality of flow equalizing plates which are arranged at intervals along the length direction of the air inlet end of the low-temperature economizer, are vertically connected with the air outlet end of the flue and are parallel to the cross section of the fourth corner flue.)

1. A flue gas flow velocity adjusting structure of an SCR denitration device is characterized by comprising a first group of guide plates (2), a second group of guide plates (3), a third group of guide plates (4) and a group of flow equalizing plates (5);

the SCR denitration device (104) is arranged on a connecting flue (6) between a high-temperature preheater (8) and a low-temperature economizer (7) of the boiler through an SCR denitration flue (1);

the connecting flues (6) are arranged along the diagonal surface in a separated way; the connecting flue (6) at one side connected with the high-temperature preheater (8) is an air outlet end of the high-temperature preheater (8) and is connected with an inlet of the SCR denitration flue (1); the connecting flue (6) at one side connected with the low-temperature economizer is the air inlet end of the low-temperature economizer (7) and is connected with the outlet of the SCR denitration flue (1);

the SCR denitration flue (1) comprises a first corner flue (101), a first straight pipe flue (102) and a second corner flue (103) which are sequentially connected between the air outlet end of the high-temperature preheater (8) and the input end of the SCR denitration device (104), and a third corner flue (105), a third straight pipe flue (106) and a fourth corner flue (107) which are sequentially connected between the output end of the SCR denitration device (104) and the air inlet end of the low-temperature economizer (7);

the first group of guide plates (2) are arranged in a fourth corner flue (107);

the second group of guide plates (3) are arranged in a second corner flue (103);

the third group of guide plates (4) comprises a flow guiding part (401) and a flow guiding part (402), are positioned at the outlet of the fourth corner flue (107), and are uniformly arranged at intervals along the height direction of the fourth corner flue (107); the flow guiding part (401) is parallel to the upper surface and the lower surface of the fourth corner flue (107), and the flow guiding part (402) is parallel to the diagonal surface of the connecting flue (6);

the group of flow equalizing plates (5) comprise a plurality of flow equalizing plates, are positioned at the air inlet end of the low-temperature economizer (7), are correspondingly arranged above the low-temperature economizer (7), and are uniformly arranged at intervals along the length direction of the air inlet end of the low-temperature economizer (7), and the flow equalizing plates (5) are perpendicular to the air outlet end of the connecting flue (6) and are parallel to the cross section of the fourth corner flue (107).

2. The flue gas flow velocity adjusting structure of the SCR denitration device according to claim 1, wherein the flow guiding part (401) and the flow guiding part (402) are rectangular flow guiding plates and are correspondingly arranged at intervals along the height direction of the fourth corner flue (107).

3. The flue gas flow velocity adjusting structure of the SCR denitration device according to claim 1, wherein the first group of guide plates (2) comprises a plurality of first guide plates, and the first guide plates are arranged in parallel with the outer contour of the fourth corner flue (107) and are uniformly arranged along the width direction of the bend of the fourth corner flue (107).

4. The flue gas flow velocity adjusting structure of the SCR denitration device according to claim 3, wherein the first guide plate comprises a circular arc-shaped guide part (201) and a rectangular guide part (202); the arc-shaped flow guide part (201) is a 90-degree arc, the arc-shaped flow guide part (201) is arranged in parallel with the outer contour of the fourth corner flue (107), and the rectangular flow guide part (202) is arranged in parallel with the side edge of the third straight pipe flue (106).

5. The flue gas flow velocity adjusting structure of the SCR denitration device according to claim 1, wherein the second group of guide plates (3) is parallel to the outer contour of the third corner flue (105).

6. The flue gas flow velocity adjusting structure of an SCR denitration device according to claim 5, wherein the third corner flue (105) comprises a first flue and a second flue;

the first flue is quadrilateral, and the air outlet end of the first flue is connected with the air inlet end of the second flue;

the second flue is in a right-angle trapezoid shape, the lower bottom edge is a second flue gas inlet end, the right-angle waist edge is a second flue gas outlet end and is connected with a third straight pipe flue (106) gas inlet end, and the non-right-angle waist edge is a second flue free end;

the second group of guide plates (3) comprises a first flue flow guide plate (301), a second flue flow guide plate (302), a second flue flow guide plate (303) and a diagonal guide plate (304).

7. The flue gas flow velocity adjusting structure of the SCR denitration device according to claim 6, wherein the first flue flow guide plate (301) is positioned in the first flue and is parallel to the side edge of the SCR denitration device (104);

the second flue guide plate (303) is positioned in the second flue, is parallel to the free end of the second flue and is arranged at intervals along the air outlet end of the first flue;

the second flue flow guide plate (302) is positioned in the second flue, is parallel to the free end of the second flue and is arranged at intervals along the diagonal line of the right angle separated by the right trapezoid;

the diagonal guide plate (304) is positioned in the second flue and is parallel to the side edge of the third straight pipe flue, and the diagonal which separates the right angle along the right trapezoid is arranged at intervals.

8. The flue gas flow velocity adjusting structure of the SCR denitration device according to claim 7, wherein the first flue flow guide plate (301) and the second flue flow guide plate (303) are both rectangular and are correspondingly arranged at intervals along the gas outlet end of the first flue.

9. The flue gas flow velocity adjusting structure of the SCR denitration device according to claim 7, wherein the second flue flow guide plate (302) and the diagonal flow guide plate (304) are rectangular and are arranged along the diagonal line of the right trapezoid separating the right angle at intervals.

Technical Field

The invention relates to the technical field of flue gas flow field simulation of a boiler tail flue, in particular to a flue gas flow velocity adjusting structure of an SCR (selective catalytic reduction) denitration device.

Background

The SCR technology is the most widely applied flue gas denitration technology in China at present, and the SCR device can be additionally arranged at a proper position through modification on a coal-fired boiler which is not matched with the SCR device during production. Before SCR denitration transformation, the flue gas at the tail part of the boiler directly enters a low-temperature economizer from the upper part to the lower part through a high-temperature preheater. The flue of some small-capacity boilers is short in flow and compact in position, the interface position of the SCR device is located between the high-temperature preheater and the low-temperature economizer, the space is relatively limited, when the SCR denitration device is additionally arranged, the flue between the high-temperature preheater and the low-temperature economizer is cut along the diagonal surface, the right side of the flue is used as an SCR inlet flue interface, and the left side of the flue is used as an SCR outlet flue interface.

The method for adjusting the flue gas flow rate at the outlet of the SCR denitration device in the prior art is to uniformly adjust the flue gas flow rates of the front wall and the rear wall by arranging two groups of flow deflectors at the corners of an SCR denitration flue and arranging a horn mouth above a low-temperature economizer, connecting the outlet of the SCR denitration device with the low-temperature economizer, and arranging a group of flow equalizing plates in a connecting flue above the low-temperature economizer to uniformly adjust the flue gas flow rates of the front wall and the rear wall, but according to the measured adjustment result, the root mean square deviation of the flue gas flow rates at the upper cross section of the low-temperature economizer, namely the root mean square deviation of the flue gas flow rates at the left side and the right side of the front wall of the SCR denitration outlet, is about 38.8 percent, the root mean square deviation of the flue gas flow rates at the left side and the right side of the rear wall is about 33.9 percent, the average flow rate deviation of the front wall and the rear wall is about 1.21m/s, and the deviation is large, therefore, the flue gas flow rate adjusting structure at the outlet of the SCR denitration device in the prior art has an insignificant adjusting effect on the flue gas flow rates, the flue gas velocity of the front wall, the rear wall and the left side and the right side of the front wall and the rear wall are greatly different, so that the flue gas velocity at an outlet is difficult to uniformly distribute, the local abrasion leakage of a low-temperature economizer pipe bundle is caused, and the normal operation of a boiler is influenced.

Disclosure of Invention

In order to solve the problems in the prior art, the invention provides a flue gas flow velocity adjusting structure of an SCR denitration device, aiming at reducing flue gas flow velocity deviation of a denitration outlet and homogenizing the flue gas flow velocity of the outlet.

In order to achieve the purpose, the invention provides the following technical scheme:

a flue gas flow velocity adjusting structure of an SCR denitration device comprises a first group of guide plates, a second group of guide plates, a third group of guide plates and a group of flow equalizing plates;

the SCR denitration device is arranged on a connecting flue between a high-temperature preheater and a low-temperature economizer of the boiler through an SCR denitration flue;

the connecting flues are arranged along the diagonal surface in a separated way; the connecting flue at one side connected with the high-temperature preheater is the air outlet end of the high-temperature preheater and is connected with the inlet of the SCR denitration flue; the connecting flue at one side connected with the low-temperature economizer is the air inlet end of the low-temperature economizer and is connected with the outlet of the SCR denitration flue;

the SCR denitration flue comprises a first corner flue, a first straight pipe flue and a second corner flue which are sequentially connected between the air outlet end of the high-temperature preheater and the input end of the SCR denitration device, and a third corner flue, a third straight pipe flue and a fourth corner flue which are sequentially connected between the output end of the SCR denitration device and the air inlet end of the low-temperature economizer;

the first group of guide plates are arranged in the fourth corner flue;

the second group of guide plates are arranged in the second corner flue;

the third group of guide plates comprise a flow guiding part and a flow guiding part, are positioned at the outlet of the fourth corner flue and are uniformly arranged at intervals along the height direction of the fourth corner flue; the flow guide part is parallel to the upper surface and the lower surface of the fourth corner flue, and the flow guide part is parallel to the diagonal surface of the connecting flue;

the group of flow equalizing plates comprise a plurality of flow equalizing plates, the flow equalizing plates are positioned at the air inlet end of the low-temperature economizer, are correspondingly arranged above the low-temperature economizer and are uniformly arranged at intervals along the length direction of the air inlet end of the low-temperature economizer, and the flow equalizing plates are perpendicular to the air outlet end of the connecting flue and are parallel to the cross section of the fourth corner flue.

Preferably, the flow guiding part and the flow guiding part are both rectangular flow guiding plates and are correspondingly arranged at intervals along the height direction of the fourth corner flue.

Preferably, the first group of guide plates comprises a plurality of first guide plates, and the first guide plates are arranged in parallel with the outer contour of the fourth corner flue and are uniformly arranged along the width direction of the bend of the fourth corner flue.

Preferably, the first baffle comprises a circular arc-shaped flow guide part and a rectangular flow guide part; the circular arc-shaped flow guide part is a 90-degree circular arc, the circular arc-shaped flow guide part is arranged in parallel with the outer contour of the fourth corner flue, and the rectangular flow guide part is parallel with the side edge of the third straight pipe flue.

Preferably, the second group of deflectors is parallel to the outer contour of the third corner flue.

Preferably, the third corner flue comprises a first flue and a second flue;

the first flue is quadrilateral, and the air outlet end of the first flue is connected with the air inlet end of the second flue;

the second flue is in a right-angle trapezoid shape, the lower bottom edge of the second flue is a second flue gas inlet end, the right-angle waist edge of the second flue is a second flue gas outlet end and is connected with a third straight pipe flue gas inlet end, and the non-right-angle waist edge of the second flue is a second flue free end;

the second group of guide plates comprise a first flue guide plate, a second flue guide plate and a diagonal guide plate.

Preferably, the first flue flow guide plate is positioned in the first flue and is parallel to the side edge of the SCR denitration device (104);

the second flue guide plate is positioned in the second flue, is parallel to the free end of the second flue and is arranged at intervals along the air outlet end of the first flue;

the second flue drainage plate is positioned in the second flue, is parallel to the free end of the second flue and is arranged at intervals along the diagonal line of the right-angle trapezoid separating right angle;

the diagonal guide plate is positioned in the second flue and is parallel to the side edge of the third straight pipe flue, and the right-angled diagonal is separated along the right-angled trapezoid and is arranged at intervals.

Preferably, the first flue flow guide plate and the second flue flow guide plate are rectangular and are correspondingly arranged at intervals along the air outlet end of the first flue.

Preferably, the second flue flow guide plate and the diagonal flow guide plate are rectangular and are arranged along the diagonal line of the right-angle trapezoid partition at intervals corresponding to the right-angle.

Compared with the prior art, the invention has the following beneficial effects:

the invention provides a flue gas flow velocity adjusting structure of an SCR (selective catalytic reduction) denitration device, which comprises a first group of guide plates, a second group of guide plates, a third group of guide plates and a group of flow equalizing plates, wherein the first group of guide plates, the second group of guide plates, the third group of guide plates and the group of flow equalizing plates are respectively arranged at the bent positions of a plurality of corner flue of an SCR denitration flue and the position of a connecting flue above a low-temperature economizer and are arranged in parallel corresponding to the outer contour of the flue, so that the flow path of flue gas passing through each bent position of the SCR denitration flue and the position of the connecting position of an SCR denitration outlet and the low-temperature economizer is optimized, the flow resistance of the flue gas flowing is reduced, the flow velocity loss of the flue gas passing through each bent position of the SCR denitration flue is reduced, the uniformity of the flue gas flow velocity is maintained, the large flow velocity deviation of the flue gas flowing into the low-temperature economizer is avoided, the local abrasion of a pipe bundle of the low-temperature economizer is reduced, and the normal operation of a boiler is ensured.

Furthermore, a third group of guide plates which are additionally arranged at the outlet of the SCR denitration flue comprises a flow guide part and a flow guide part, wherein the smoke subjected to SCR denitration treatment is uniformly distributed through a plurality of rectangular flow guide parts, and then the smoke passes through a plurality of rectangular flow guide parts which are correspondingly arranged and are parallel to the cutting diagonal surface of the connecting flue, so that the flow direction of the smoke entering the connecting flue interface is changed, the smoke is consistent with the cutting direction of the connecting flue, and the smoke flow resistance is optimized.

Furthermore, the invention replaces the original bell mouth arrangement, which causes the flow direction of the flue gas flowing into the low-temperature economizer to be inconsistent and the flow speed to have deviation.

Drawings

FIG. 1 is a general view of a deflector arrangement of an SCR denitration device according to the present invention;

FIG. 2 is a schematic view of the arrangement of the upper deflector of the low-temperature economizer of the present invention;

FIG. 3 is a schematic view of a first group of baffle arrangements of the present invention;

FIG. 4 is a schematic view of a second group of baffle arrangements of the present invention;

fig. 5 is a schematic view of a third set of baffles and a set of flow equalization plates according to the present invention.

In the figure, an SCR denitration flue 1, a first corner flue 101, a first straight pipe flue 102, a second corner flue 103, an SCR denitration device 104, a third corner flue 105, a third straight pipe flue 106, a fourth corner flue 107, a first group of guide plates 2, a circular arc-shaped guide part 201, a rectangular guide part 202, a second group of guide plates 3, a first flue guide plate 301, a second flue guide plate 302, a second flue guide plate 303, a diagonal guide plate 304, a third group of guide plates 4, a guide part 401, a guide part 402, a group of flow equalizing plates 5, a connecting flue 6, a low-temperature economizer 7 and a high-temperature preheater 8.

Detailed Description

The present invention will now be described in further detail with reference to specific examples, which are intended to be illustrative, but not limiting, of the invention.

As shown in fig. 1 and 2, the present invention provides a flue gas flow rate adjusting structure of an SCR denitration device, which includes a first group of guide plates 2, a second group of guide plates 3, a third group of guide plates 4 and a group of flow equalizing plates 5; the SCR denitration device 104 is arranged on a connecting flue 6 between a high-temperature preheater 8 and a low-temperature economizer 7 of the boiler through an SCR denitration flue 1; the connecting flue 6 at one side connected with the high-temperature preheater 8 is an air outlet end of the high-temperature preheater 8 and is connected with an inlet of the SCR denitration flue 1, the connecting flue 6 at one side connected with the low-temperature economizer is an air inlet end of the low-temperature economizer 7 and is connected with an outlet of the SCR denitration flue 1, and the SCR denitration flue 1 comprises a first corner flue 101, a first straight pipe flue 102 and a second corner flue 103 which are sequentially connected between the air outlet end of the high-temperature preheater 8 and an input end of an SCR denitration device 104, a third corner flue 105, a third straight pipe flue 106 and a fourth corner flue 107 which are sequentially connected between an output end of the SCR denitration device 104 and the air inlet end of the low-temperature economizer 7; the first group of guide plates 2 are arranged in the fourth corner flue 107; the second group of guide plates 3 are arranged in the second corner flue 103; the third group of guide plates 4 comprises a flow guiding part 401 and a flow guiding part 402, are positioned at the outlet of the fourth corner flue 107 and are uniformly arranged at intervals along the height direction of the fourth corner flue 107, the flow guiding part 401 is parallel to the upper surface and the lower surface of the fourth corner flue 107, and the flow guiding part 402 is parallel to the diagonal surface of the connecting flue 6; the group of flow equalizing plates 5 comprises a plurality of flow equalizing plates, the flow equalizing plates are located at the air inlet end of the low-temperature economizer 7 and correspondingly arranged above the low-temperature economizer 7, the flow equalizing plates are uniformly arranged at intervals along the length direction of the air inlet end of the low-temperature economizer 7, and the flow equalizing plates 5 are perpendicular to the air outlet end of the connecting flue 6 and are parallel to the cross section of the fourth corner flue 107.

In the invention, an SCR denitration device 8 is positioned at the diagonal surface cutting part of a connecting flue 6 between a high-temperature preheater 8 and a low-temperature economizer 7, an inlet and an outlet of the SCR denitration device 8 are respectively connected with the connecting flues 6 at the left side and the right side which are cut along the diagonal surface, flue gas is output from the high-temperature preheater 8, enters the SCR denitration device 8 through the connecting flue 6 for treatment, is output from an outlet after passing through an SCR denitration flue 1, and then enters the low-temperature economizer 7 connected with the outlet from the upper part, and the flue gas needs to pass through a plurality of bent channels in the SCR denitration flue 1 in the transmission process, so that the velocity distribution is not uniform in the flow process of the flue gas, and the flow velocity of the flue gas entering the low-temperature economizer 7 has deviation, therefore, a plurality of groups of guide plates are arranged at a plurality of corner positions of the SCR denitration flue 1, and a group of flow equalizing plates 5 are arranged at the connecting flue 6 above the low-temperature economizer 7, therefore, the flow paths of the flue gas passing through the bends of the SCR denitration flue 1 and the connection between the SCR denitration outlet and the low-temperature economizer 7 are optimized, the flow resistance of the flue gas during flowing is reduced, the uniformity of the flow velocity of the flue gas is kept, the flue gas flowing into the low-temperature economizer 7 is prevented from having large flow velocity deviation, the local abrasion of the tube bundle of the low-temperature economizer 7 is reduced, and the normal operation of the boiler is ensured.

Further, as shown in fig. 5, the flow guiding part 401 and the flow guiding part 402 are both rectangular flow guiding plates and are correspondingly arranged at intervals along the height direction of the fourth corner flue 107.

According to the invention, a plurality of guide plates are uniformly arranged at the outlet of the SCR denitration flue 1 along the height direction of the flue at intervals, the flue gas subjected to SCR denitration treatment is uniformly distributed through a plurality of rectangular guide parts 401, and then the flue gas passes through a plurality of rectangular guide parts 402 correspondingly arranged and is parallel to the cutting diagonal surface of the connecting flue 6, so that the flow direction of the flue gas entering the interface of the connecting flue 6 is changed, the flow direction of the flue gas is consistent with the cutting direction of the connecting flue 6, and the flow resistance of the flue gas is optimized.

Further, as shown in fig. 5, the extension line of the flow guiding part 402 is disposed corresponding to the position of the partial flow equalizing plate 5, and the flow equalizing plate 5 is rectangular.

The invention replaces the original bell mouth arrangement, which causes the inconsistent flow direction of the flue gas flowing into the low-temperature economizer 7 and the deviation of the flow speed, the invention arranges a group of rectangular flow equalizing plates 5 at the outlet of the connecting flue 6 connected with the low-temperature economizer 7 along the length direction at intervals, which can evenly distribute the flue gas entering the low-temperature economizer 7 and change the flow direction of the flue gas to make the flue gas consistent with the inlet direction of the low-temperature economizer 7, thus realizing the better uniformity of the flow speed distribution of the flue gas, avoiding the flue gas flowing into the low-temperature economizer 7 from having larger flow speed deviation and reducing the local abrasion of the tube bundle of the low-temperature economizer 7.

Further, as shown in fig. 3, the first group of baffles 2 includes a plurality of first baffles, the first baffles are arranged in parallel with the outer contour of the fourth corner flue 107 and are uniformly arranged along the width direction of the bend of the fourth corner flue 107; the first guide plate comprises a circular arc-shaped guide part 201 and a rectangular guide part 202; the circular arc-shaped flow guide portion 201 is a circular arc of 90 degrees, the circular arc-shaped flow guide portion 201 is arranged in parallel with the outer contour of the fourth corner flue 107, and the rectangular flow guide portion 202 is parallel to the side edge of the third straight pipe flue 106.

According to the invention, a plurality of first guide plates are uniformly arranged at intervals according to the width of the fourth corner flue 107, and a rectangular flow guiding part 202 and an arc flow guiding part 201 are correspondingly arranged according to the outline of the fourth corner flue 107, the flow guiding part is arranged for uniformly distributing the flue gas entering the fourth corner flue 107, and the arc part is arranged for changing the flow direction of the flue gas, optimizing the flow path of the flue gas when the flue gas passes through an arc bend, and reducing the flow resistance of the flue gas, thereby reducing the flow speed deviation of the flue gas caused by the flue gas passing through the bend.

Further, as shown in fig. 4, the second group of baffles 3 is parallel to the outer contour of the third corner flue 105.

Further, the third corner chimney 105 includes a first chimney and a second chimney; the first flue is quadrilateral, and the air outlet end of the first flue is connected with the air inlet end of the second flue; the second flue is in a right-angle trapezoid shape, the lower bottom edge is a second flue gas inlet end, the right-angle waist edge is a second flue gas outlet end and is connected with a third straight pipe flue 106 gas inlet end, and the non-right-angle waist edge is a second flue free end;

the second group of baffles 3 comprises a first flue flow guide plate 301, a second flue flow guide plate 302, a second flue flow guide plate 303 and a diagonal flow guide plate 304; the first flue flow guide plate 301 is positioned in the first flue and is parallel to the side edge of the SCR denitration device 104; the second flue guide plate 303 is positioned in the second flue, is parallel to the free end of the second flue and is arranged at intervals along the air outlet end of the first flue; the second flue flow guide plate 302 is positioned in the second flue, is parallel to the free end of the second flue and is arranged at intervals along the diagonal line of the right-angle trapezoid separating right angles; the diagonal guide plate 304 is positioned in the second flue, is parallel to the side edge of the third straight pipe flue, and is arranged at intervals along the diagonal of the right-angle trapezoid partition right angle.

Further, the first flue flow guide plate 301 and the second flue flow guide plate 303 are rectangular and are correspondingly arranged at intervals along the air outlet end of the first flue.

Further, the second flue flow guide plate 302 and the diagonal flow guide plate 304 are rectangular and are arranged at intervals along the diagonal line of the right trapezoid separating the right angle.

The second corner flue 103 and the third corner flue 105 of the present invention are symmetrical flues. The third corner flue 105 is of an irregular structure, and is internally provided with a plurality of corner turning positions, so that the difference of flow velocity loss is large when flue gas passes through the position, the flow velocity distribution deviation is obvious, if the arc-shaped guide plate cannot well reduce the flow velocity deviation, the invention is provided with a plurality of flow guide plates and flow guide plates at corresponding corners according to the outline shape of the third corner flue 105, the air outlet end of the first flue is uniformly provided with a plurality of rectangular first flue flow guide plates 301 at intervals along the width direction, the flue gas entering the third corner flue 105 can be uniformly distributed, and then the flue gas passes through a plurality of corresponding rectangular second flue flow guide plates 302 which are parallel to the free end of the second flue, the flow direction of the flue gas can be changed, the flow path of the flue gas passing through the third corner flue 105 is optimized, the flow resistance of the flue gas is kept consistent with the corner direction of the flue gas, and then the flow resistance of the flue gas is uniformly distributed through a plurality of rectangular second flue flow guide plates 302 arranged on the right-angle trapezoid separating right-angled diagonal line of the second flue The flue gas, the flow direction of flue gas is changed again through a plurality of rectangle diagonal guide plates 304 that correspond the setting, makes it and the third straight tube flue 106 direction at rear keep parallel, consequently, the great difference that leads to because flue gas velocity of flow loss is uneven in flue gas velocity distribution that the at utmost has reduced because there is the corner in the flue bend.

Example 1

This embodiment has designed SCR denitrification facility's flue gas velocity of flow adjustment structure, and the concrete design is as follows:

1) uniformly arranging 5 first guide plates at a fourth corner flue 107 of the SCR denitration flue 1 along the width direction, wherein each first guide plate comprises a circular arc-shaped guide part 201 and a rectangular flow guide part 202, each circular arc-shaped guide part 201 is a 90-degree circular arc, each circular arc-shaped guide part 201 is arranged in parallel with the outer contour of the fourth corner flue 107, each rectangular flow guide part 202 is parallel to the side edge of the third straight pipe flue 106, the radius of each circular arc-shaped guide part 201 is 500mm, and the length of each rectangular flow guide part 202 is 500 mm;

2) arranging a second group of guide plates 3 at a third corner flue 105 of the SCR denitration flue 1, wherein the second group of guide plates comprises a first flue flow guide plate 301, a second flue flow guide plate 302, a second flue flow guide plate 303 and a diagonal guide plate 304; the first flue flow guide plates 301 are arranged at intervals along the air outlet end of the first flue and are parallel to the side edge of the SCR denitration device 104; the second flue flow guide plate 302 and the second flue flow guide plate 303 are both positioned in the second flue and are parallel to the free end of the second flue, the second flue flow guide plates 303 are arranged at intervals along the air inlet end of the second flue, and the second flue flow guide plates 302 are arranged at intervals along the right angle trapezoid-shaped right angle-separated diagonal; the diagonal guide plates 304 are positioned in the second flue, are arranged at intervals along the diagonal of the right-angle trapezoid separating the right angles, and are parallel to the side edge of the third straight pipe flue 106; the first flue flow guide plate 301 and the second flue flow guide plate 303 are both rectangular, the lengths of the first flue flow guide plate and the second flue flow guide plate are both 200mm, and the first flue flow guide plate and the second flue flow guide plate are correspondingly arranged at intervals along the gas outlet end of the first flue; the spacing distance of the second flue guide plate 303 is 527mm, which is 2 times of the spacing distance of the first flue guide plate 301, the second flue guide plate 302 and the diagonal guide plate 304 are both rectangular, 9 pieces of the second flue guide plate and the diagonal guide plate are respectively arranged, and are correspondingly arranged at intervals along the diagonal line of the right-angle trapezoid, the spacing distance is 386.5mm, the length of the second flue guide plate 302 is 400mm, and the length of the diagonal guide plate 304 is 200 mm;

3) a third group of guide plates 4 are arranged at the outlet of the SCR denitration flue 1 and comprise a flow guiding part 401 and a flow guiding part 402; the flow guiding part 401 is parallel to the upper surface and the lower surface of the fourth corner flue 107, the flow guiding part 402 is parallel to the diagonal surface of the connecting flue 6 and is arranged at intervals along the height direction of the fourth corner flue 107, wherein the extension line of the flow guiding part 402 is arranged corresponding to the position of the part of the flow equalizing plate 5, the flow guiding part 401 and the flow guiding part 402 are both rectangular and are respectively provided with 7 blocks, the flow guiding part 401 and the flow guiding part 402 are arranged at intervals along the height direction of the fourth corner flue 107, the length of the flow guiding part 401 is 200mm, and the length of the flow guiding part 402 is 400 mm;

4) a group of flow equalizing plates 5 are arranged in the flue above the low-temperature economizer 7, the flow equalizing plates 5 are parallel to the air outlet end of the fourth corner flue 107 and are arranged at intervals along the length direction of the air outlet connector of the connecting flue 6, the flow equalizing plates 5 are rectangular, the height of the flow equalizing plates 5 is 300mm, and the transverse interval distance is 125 mm.

By arranging the flue gas flow rate adjusting structure of the SCR denitration device, the flue gas flow rate root mean square deviation of the left side of the front wall, the flue gas flow rate root mean square deviation of the right side of the front wall, the flue gas flow rate root mean square deviation of the left side of the rear wall, and the flue gas flow rate root mean square deviation of the right side of the rear wall are 13.0%, 14.0%, 12.9% and 0.26m/s respectively at the upper section of the low-temperature economizer 7 through measurement of the SCR denitration outlet, and therefore, the flue gas flow rate deviation of the denitration outlet can be obviously reduced and the flue gas flow rate of the uniform outlet can be realized through the flue gas flow rate adjusting structure of the SCR denitration device.