TWI802860B - Absorption tower of desulfurization unit - Google Patents

Abstract

[Problem] Improve desulfurization performance and dust removal performance. [solution] The absorption tower (1) includes an absorption tower main body (2), a liquid column nozzle (20), and an atomizing nozzle (30). The main body (2) of the absorption tower has an internal space (3) through which the exhaust gas flows from the bottom to the top. The liquid column nozzle (20) is arranged in the inner space (3), and sprays the cleaning liquid upward in the form of a liquid column. The atomizing nozzle (30) is arranged in the inner space (3) above the liquid column nozzle (20), and sprays the cleaning liquid downward in a conical shape. The atomizing nozzle (30) is arranged at a height higher than the highest reaching height (H4) of the liquid column (26) formed by the cleaning liquid sprayed from the liquid column nozzle (20).

Description

Absorption tower of desulfurization unit

This invention relates to an absorption tower for a desulfurization plant for removing sulfur oxides from exhaust gas.

For example, air pollutants such as SO _x (sulfur oxides) are contained in exhaust gas discharged from combustion facilities such as boilers. As a method for reducing SO _x contained in exhaust gas, there is a wet desulfurization method in which SO ₂ (sulfur dioxide gas) is absorbed and removed with a washing liquid (absorbing liquid) such as an alkaline aqueous solution or an absorbent suspension.

As a desulfurization device using the wet desulfurization method described above, there is known a liquid column type absorption tower that sprays a cleaning liquid upward to clean the exhaust gas (for example, refer to Patent Document 1). The liquid-column absorption tower forms a liquid column above the liquid-column nozzle with the washing liquid sprayed from the liquid-column nozzle. The cleaning liquid formed in the liquid column is scattered on the top of the upper spray and then descends to minimize the collision with the cleaning liquid sprayed from the liquid column nozzle. The miniaturized cleaning solution is brought into contact with the exhaust gas to absorb air pollutants contained in the exhaust. Moreover, the coal dust contained in the exhaust gas can be removed from the exhaust gas by the miniaturized cleaning solution. [Prior Art Literature] [Patent Document]

[Patent Document 1] Japanese Patent Application Laid-Open No. 10-128053

[Problem to be Solved by the Invention]

In recent years, there is a tendency to strengthen the emission control of air pollutants such as sulfur oxides and soot. The emission of air pollutants can be reduced by using low-sulfur fuel with a low sulfur content, or high-quality fuel such as low-dust fuel that generates less dust from combustion.

However, the use of high-priced high-quality fuel will lead to an increase in operating costs. Therefore, it is expected to use high-sulfur fuel with a high sulfur content, or a cheap fuel such as high-dust fuel with a large amount of dust generated by combustion, and to achieve clean energy. Improvement of sulfur performance and dust removal performance.

Therefore, an object of the present invention is to provide an absorption tower of a desulfurization device capable of improving desulfurization performance and dust removal performance. [Means used to solve the problem]

In order to achieve the above object, the first aspect of the present invention is an absorption tower of a desulfurization device for absorbing and discharging sulfur oxides in exhaust gas with a cleaning solution, and includes an absorption tower main body, a liquid column nozzle, and an atomizing nozzle. The main body of the absorption tower has an internal space in which the exhaust gas flows from the bottom to the top. The liquid column nozzle is arranged in the inner space, and sprays the cleaning liquid upward in the form of a liquid column. The atomizing nozzle is installed in the inner space above the liquid column nozzle, and sprays the cleaning liquid downward in a conical shape. The atomizing nozzle is a hollow conical nozzle with a circular spray pattern, and is arranged at a height above the highest reaching height of the liquid column formed by the cleaning liquid sprayed from the liquid column nozzle. The cleaning liquid sprayed from the atomizing nozzle spreads in the form of a liquid film after being sprayed out, and then the liquid film is split as it falls to form a group of liquid film split droplets. The liquid column nozzle is arranged at a height lower than the generation height of the liquid film splitting droplet group of the cleaning liquid sprayed from the atomizing nozzle.

In the first aspect, the liquid column nozzle that sprays the cleaning liquid upward in the form of a liquid column is installed in the internal space of the absorption tower main body, and the cleaning liquid is installed at a position higher than the position where the liquid column nozzle is provided in the internal space so that the cleaning liquid The atomizing nozzle sprays upward in a conical shape. Compared with the absorption tower equipped with only one of the liquid column nozzle and the atomizing nozzle, the range where the cleaning liquid and the exhaust gas can be in contact with the gas and liquid (gas-liquid contact range) is toward the The flow direction of the exhaust gas expands. Therefore, the desulfurization performance and dust removal performance can be improved compared with the absorption tower provided with only one of the liquid column nozzle and the atomization nozzle.

In addition, the atomizing nozzle is a hollow conical nozzle with a circular spray pattern. The cleaning liquid sprayed from the atomizing nozzle expands into a liquid film after being sprayed out, and then the liquid film is split into liquid film split droplets as it falls. group. Arrange the atomizing nozzle at a height higher than the highest reaching position of the liquid column formed by the cleaning liquid sprayed from the liquid column nozzle, and arrange the liquid column nozzle at a height higher than that of the cleaning liquid sprayed from the atomizing nozzle. The generation height of the membrane split droplet group is lower, so the interference between the droplets from the liquid column nozzle and the droplets from the atomizing nozzle can be suppressed, and the desulfurization performance and dust removal performance can be further improved.

A second aspect of the present invention is the absorption tower of the first aspect, and the liquid column nozzle is a liquid column formed by the cleaning liquid sprayed from the liquid column nozzle, and is arranged in a liquid column that is not in contact with the cleaning liquid sprayed from the atomizing nozzle. The height position of the membrane interference.

In the second aspect, the liquid column formed by the cleaning liquid sprayed from the liquid column nozzle does not interfere with the liquid film of the cleaning liquid sprayed from the atomizing nozzle, so the interference caused by the liquid column and the liquid film can be prevented Decrease in desulfurization performance resulting in uneven cleaning solution.

The third aspect of the present invention is the absorption tower of the first aspect, and the generation height of the liquid film split droplet group of the cleaning liquid sprayed from the atomizing nozzle is higher than the liquid column formed by the cleaning liquid sprayed from the liquid column nozzle. The maximum reach height is higher.

In the third aspect, since the generation height of the liquid film splitting droplet group of the cleaning liquid sprayed from the atomizing nozzle is higher than the maximum reaching height of the liquid column formed by the cleaning liquid sprayed from the liquid column nozzle, it can be Interference between droplets from the liquid column nozzle and droplets from the atomizing nozzle is further suppressed.

A fourth aspect of the present invention is the absorption tower of the first to third aspects, and includes an atomizing head that extends substantially horizontally across the internal space, supports the atomizing nozzle, and supplies the cleaning liquid to the atomizing nozzle. . The main body of the absorption tower has a substantially vertical cylindrical peripheral wall. The inner peripheral surface of the peripheral wall partitions the interior space. The peripheral wall is provided with an exhaust gas introduction port through which exhaust gas flows. On the inner peripheral surface of the peripheral wall, above the upper edge of the exhaust air inlet and at least part of the height range below the atomizing head, a slip-out prevention material protruding from the inner peripheral surface into the inner space is provided.

In the fourth aspect, since the slip-out preventing material is provided on the outer peripheral portion of the internal space where exhaust gas is likely to leak, the cleaning liquid and the gas-liquid are not in contact, and the exhaust gas discharged from the absorption tower can be reduced, and the degassing rate can be further improved. Sulfur performance and dust removal performance. [Invention effect]

According to the present invention, desulfurization performance and dust removal performance can be improved.

(first embodiment)

The absorption tower 1 of the desulfurization device related to the first embodiment of the present invention will be described with reference to Fig. 1 to Fig. 4 . The desulfurization device is a wet-type limestone-gypsum exhaust gas desulfurization device that absorbs and removes sulfur oxides from the exhaust gas containing sulfur oxides generated by a combustion device (not shown) with a cleaning solution (absorbing liquid). Absorption tower 1 for exhaust gas of sulfur oxides. The combustion device includes an engine such as a diesel engine, a gas turbine engine, or a steam turbine engine, in addition to a boiler in a thermal power plant or the like. In addition, a blank arrow F in the figure indicates the flow direction of the exhaust gas.

(Structure of absorption tower) As shown in FIG. 1 , the absorption tower 1 includes an absorption tower main body 2 having an internal space 3 into which exhaust gas from a combustion device is introduced. The main body 2 of the absorption tower has a cylindrical surrounding wall 6 that is approximately vertically erected between the bottom surface 4 and the ceiling surface 5. By the inner peripheral surface 7 of the bottom surface 4, the ceiling surface 5 and the surrounding wall 6, the upper and lower sides are separated. Extended interior space3. The peripheral wall 6 may be cylindrical or rectangular.

An exhaust gas inlet 8 is provided on one side (front side) of the peripheral wall 6 , and an inlet pipe (exhaust gas inlet) 9 is connected to the exhaust gas inlet 8 . An exhaust outlet 10 is provided on the upper portion of the peripheral wall 6 on the other side (rear side) opposite to the exhaust inlet 8 , and an outlet pipe (exhaust discharge portion) 11 is connected to the exhaust outlet 10 . In the exhaust gas outlet 10 , the upper surface of the outlet pipe 11 is continuous from the ceiling surface 5 of the absorption tower main body 2 . The inlet pipe 9 and the outlet pipe 11 may be cylindrical or rectangular. Exhaust gas discharged from the combustion device is introduced into the internal space 3 from the exhaust gas introduction port 8 through the inlet pipe 9 . The introduced exhaust gas flows from the bottom to the top in the internal space 3 and is discharged from the exhaust gas outlet 10 through the outlet pipe 11 .

Set in the inner space 3 of the absorption tower main body 2: the liquid column head (liquid column tube) 21 that is equipped with at least one (this embodiment is plural) liquid column nozzle 20, and possesses at least one (this embodiment is plural) An atomizing head (atomizing pipe) 31 of the atomizing nozzle 30 . The liquid column nozzle 20 is arranged above the upper edge of the exhaust gas inlet 8 , and the atomizing nozzle 30 is arranged above the liquid column nozzle 20 . That is, the height H1 of the liquid column nozzle 20 (the height of the injection port) is higher than the height H3 of the upper edge of the exhaust gas introduction port 8, and the height of the atomizing nozzle 30 (the height of the injection port) H2 is higher than that of the liquid column nozzle 20. The height H1 is high (H3<H1<H2). Each height is, for example, the ground height from the ground where the absorption tower main body 2 is installed.

The liquid column nozzle 20 is configured to spray the cleaning liquid upward (in the same direction as the flow direction of the exhaust gas) in the form of a liquid column. The liquid column head 21 extends substantially horizontally across the inner space 3 . The liquid column head 21 supports the liquid column nozzle 20 and supplies cleaning liquid to the liquid column nozzle 20 . The arrangement form of the plurality of liquid column nozzles 20 is not particularly limited, but it is preferable to arrange them equally on the nozzle arrangement surface of the internal space 3 .

The atomizing nozzle 30 is configured to spray the washing liquid downward (in the direction opposite to the flow direction of the exhaust gas) in a conical shape. The atomizing head 31 extends substantially horizontally across the inner space 3 . The atomizing head 31 supports the atomizing nozzle 30 and supplies cleaning liquid to the atomizing nozzle 30 . The arrangement form of the plurality of atomizing nozzles 30 is not particularly limited, but it is preferable to arrange them evenly on the nozzle arrangement surface of the internal space 3 .

The atomizing nozzle 30 of this embodiment is a hollow cone nozzle whose spray pattern is circular (the spray shape is a hollow cone shape). In addition, the atomizing nozzle 30 is not limited to a hollow cone nozzle, as long as it can spray the cleaning liquid in a cone shape. For example, other single-phase (one-fluid) nozzles such as a full-cone nozzle that sprays forward in a circular shape may be used, or a two-phase (two-fluid) nozzle that sprays the cleaning liquid of mixed gas in the form of fine particles. .

As the cleaning liquid, for example, a liquid containing an alkaline agent, sea water, or the like is used. As the alkaline agent, for example, CaCO ₃ , NaOH, Ca(OH) ₂ , NaHCO ₃ , Na2CO ₃ and the like are used.

A liquid column 26 is formed above the liquid column nozzle 20 by the cleaning liquid sprayed from the liquid column nozzle 20 . The cleaning liquid forming the liquid column 26 balances the upward penetrating force and gravity, and descends after being dispersed at the liquid column reaching part (top of the upper spray) 27 of the liquid column at the highest reaching position. The cleansing solution is miniaturized after conflict. The droplet group (a large number of droplets) of the miniaturized cleaning liquid that fell after the liquid column 26 splits from the liquid column reaching portion 27 is called the liquid column split droplet group 28 . The liquid column split droplet group 28 is in gas-liquid contact with the exhaust gas, and absorbs air pollutants such as SO _x (sulfur oxides) contained in the exhaust gas. Furthermore, the liquid column split droplet group 28 removes the soot contained in the exhaust gas from the exhaust gas.

The atomizing nozzle 30 is disposed above the highest reaching height of the liquid column 26 formed by the cleaning liquid sprayed from the liquid column nozzle 20 (the liquid column reaching portion 27 ). That is, the height H4 of the liquid column reaching part 27 is higher than the height H1 of the liquid column nozzle 20, and the height H2 of the atomizing nozzle 30 is higher than the height H4 of the liquid column reaching part 27 (H1<H4<H2).

The subsequent cleaning solution sprayed from the atomizing nozzle 30 expands in the form of a liquid film (the liquid film 36 expands into a hollow conical shape), and the liquid film 36 splits into droplets as it falls. The liquid film splitting droplet group (or atomized splitting droplet group) 37 is referred to as the liquid film splitting droplet group (or atomized splitting droplet group) 37 , which is the cleaning liquid droplet group (plurality of droplets) that is split from the liquid film 36 and then miniaturized. The liquid film splitting droplet group 37 is in contact with the exhaust gas and absorbs air pollutants such as SO _x (sulfur oxides) contained in the exhaust gas. Furthermore, the liquid film splitting droplet group 37 removes the soot contained in the exhaust gas from the exhaust gas.

The inner space 3 of the absorption tower main body 2 is divided into: the lower space 14 communicated with the inlet pipe 9 through the exhaust gas inlet 8; the upper space 15 communicated with the outlet pipe 11 through the exhaust gas outlet 10; the lower space 14 and the upper space 15 The gas-liquid contact area 16 between them; and the liquid storage part 13 below the lower space 14. The gas-liquid contact area 16 is the lower limit with the injection port of the liquid column nozzle 20, and the area of the upper limit with the injection port of the atomizing nozzle 30 (above the height of the injection port of the liquid column nozzle 20, and the injection port of the atomizing nozzle 30 The area below the height), the gas-liquid contact between the cleaning liquid and the exhaust gas is mainly carried out in the gas-liquid contact area 16.

The gas-liquid contact region 16 is divided into a first gas-liquid contact region 16A below the height of the liquid column reaching part 27 of the liquid column 26 formed by the liquid column nozzle 20, and a second gas-liquid contact region 16A above the height of the liquid column reaching part 27. Gas-liquid contact area 16B. That is, in the internal space 3 , the upper space 15 , the second gas-liquid contact region 16B, the first gas-liquid contact region 16A, the lower space 14 , and the liquid reservoir 13 are arranged in order from above. The cleaning liquid sprayed from the liquid column nozzle 20 is in contact with the gas-liquid of the exhaust, mainly in the first gas-liquid contact area 16A, and the cleaning liquid sprayed from the atomizing nozzle 30 is in contact with the gas-liquid of the exhaust, mainly It is carried out in the second gas-liquid contact area 16B.

The fine droplets flowing along with the exhaust gas are removed by the mist eliminator 12 installed on the upper part of the absorption tower 1 (the outlet pipe 11 in this embodiment). The gas (processing gas) of fine liquid droplets removed by the demister 12 is heated up as necessary by a reheating device (not shown) installed on the downstream side of the absorption tower 1, and discharged from a chimney (not shown) . In addition, a mist eliminator 12 may be provided in the upper space 15 of the absorption tower main body 2 .

The lower part of the internal space 3 of the absorption tower main body 2 (the space below the lower space 14 ) constitutes a liquid storage part (absorption tower tank) 13 for storing cleaning liquid. The cleaning liquid is sprayed from the liquid column nozzle 20 and the atomizing nozzle 30 , contacts the exhaust gas and absorbs sulfur oxides, and then falls in the internal space 3 . Stored in the liquid storage part 13. The liquid level (overflow surface) of the cleaning liquid stored in the liquid storage part 13 is set at a position lower than the lower end edge of the exhaust gas introduction port 8 . When the cleaning liquid stored in the liquid storage unit 13 contains the reaction product generated from the SO _x absorbed from the exhaust gas or contains the oxidation product generated from the oxidation reaction product. The reaction product is, for example, sulfite generated by the SO ₂ absorbed by the cleaning solution, and the oxidation product is, for example, gypsum. When an oxidation product is generated, an air supply device (not shown) for supplying air to the stagnant cleaning solution may be provided in the liquid storage unit 13 .

The absorption tower 1 includes a first cleaning liquid circulation line 22 and a second cleaning liquid circulation line 32 . The first cleaning liquid circulation line 22 is configured to discharge the cleaning liquid stored in the liquid storage part 13 , and can send the liquid to the liquid column nozzle 20 through the liquid column head 21 . The second cleaning liquid circulation line 32 is configured to discharge the cleaning liquid stored in the liquid storage part 13 , and can send the liquid to the atomizing nozzle 30 through the atomizing head 31 . In addition, the absorption tower 1 may include a washing liquid introduction line (not shown) for introducing the washing liquid from the outside of the absorption tower main body 2 to the liquid storage part 13 .

The first cleaning liquid circulation line 22 includes: at least one first circulation pipe 23 connecting the liquid storage part 13 and the liquid column head 21; a first circulation pump 24 arranged in the middle of the first circulation pipe 23; The valve 25 of the first circulation pipe 23 on the upstream side of the circulation pump 24 . The first circulation pump 24 discharges the cleaning liquid stored in the liquid storage unit 13 , and sends it to the liquid column nozzle 20 through the first circulation pipe 23 and the liquid column head 21 . The valve 25 may be an on-off valve or a flow rate adjustment valve. In addition, a valve capable of opening and closing the first circulation pipe 23 may be provided on the downstream side of the first circulation pump 24 instead of or added to the valve 25 .

The second cleaning liquid circulation line 32 includes: at least one second circulation piping 33 connecting the liquid storage part 13 and the atomizing head 31; the second circulation pump 34 arranged in the middle of the second circulation piping 33; 2 The valve 35 of the second circulation pipe 33 on the upstream side of the circulation pump 34. The second circulation pump 34 discharges the cleaning liquid stored in the liquid storage part 13 , and sends it to the atomization nozzle 30 through the second circulation pipe 33 and the atomization head 31 . The valve 35 may be an on-off valve or a flow rate adjustment valve. In addition, a valve capable of opening and closing the second circulation pipe 33 may be provided on the downstream side of the second circulation pump 34 instead of or added to the valve 35 .

In the inner space 3 of the absorption tower 1, the first gas-liquid contact area 16A of the liquid column nozzle 20 and the second gas-liquid contact area 16B of the atomizing nozzle 30 are arranged in the flow direction of the exhaust gas, and the first gas-liquid contact area 16B is arranged. 16A and the second gas-liquid contact region 16B form a gas-liquid contact region 16 . The droplet group from the liquid column nozzle 20 in the first gas-liquid contact region 16A and the droplet group from the atomizing nozzle 30 in the second gas-liquid contact region 16B are as described below, and the particle size distribution is different from the dispersion of the droplets. , the exhaust gas passes through both of the first gas-liquid contact region 16A and the second gas-liquid contact region 16B, thereby increasing the gas-liquid contact ratio.

(Expansion of the particle size distribution of the droplet group) Referring to Fig. 2, the particle size distribution (droplet distribution of the liquid column) D1 of the droplet group sprayed and split from the liquid column nozzle 20, and the particle size distribution (atomization) of the droplet group sprayed from the atomizing nozzle 30 are illustrated. The droplet distribution) D2 relationship. FIG. 2 shows the droplet distribution D1 of the liquid column with a solid line, and the atomized droplet distribution D2 with a dotted line.

FIG. 2 is a conceptual diagram of the droplet distribution (particle size distribution) of the liquid column and the droplet distribution (particle size distribution) of the atomization. As shown in Figure 2, the liquid droplet group (atomized and split droplet group 37 in Figure 1) that is split and produced from the cleaning liquid sprayed from the atomizing nozzle 30 has a relatively small particle size distribution D2, and the sprayed from the liquid column nozzle 20 The liquid droplet group (the liquid column split droplet group 28 in FIG. 1 ) generated by splitting the cleaning liquid has a relatively large particle size distribution D1. Therefore, in the internal space 3 of the absorption tower main body 2 through which the exhaust gas flows, a group of liquid droplets having a wide distribution of particle diameters can be generated.

(dispersion of droplet group) As shown in Figure 3, atomizing nozzle 30 is easy to produce droplet (atomization and splitting droplet group 37) on the extension line of liquid film 36, and liquid column nozzle 20 is easy to produce droplet (liquid column) vertically below liquid column arrival portion 27. Splitting droplet populations 28). The dispersion direction of liquid column split droplet group 28 is indicated by arrow 40 and the dispersion direction of atomized split droplet group 37 is shown in FIG. 3 by arrow 41 . As mentioned above, the dispersion direction of the liquid column split droplet group 28 is different from the dispersion direction of the atomized split droplet group 37, so the droplet groups 28, 37 of the cleaning liquid can be uniformly dispersed in the internal space of the absorption tower main body 2. 3 (the horizontal section of the gas-liquid contact area 16).

(Interference of droplet groups) FIG. 4 is a schematic diagram schematically showing the interference between the liquid column splitting droplet group 28 and the liquid film splitting droplet group 37 . 4( a ) shows a state where the liquid column reaching part 27 reaches the liquid film 36 and interferes, and (b) shows a state where the liquid column reaching part 27 does not reach the liquid film 36 and does not interfere. In the absorption tower 1 of this embodiment in which the liquid column nozzle 20 and the atomizing nozzle 30 are combined, there is a possibility that the liquid droplet groups interfere with each other. There are three main considerations for suspenseful matters arising from interference.

The first suspense issue is the fusion of liquid droplets. When the liquid column splitting droplet group 28 merges with the atomized splitting droplet group 37, the droplet will become coarser and the surface area of the droplet group will decrease, which is not conducive to the gas-liquid contacting flue gas desulfurization device.

The second suspense matter is the collision of the droplets. Collisions between droplets include: the collision of the liquid column splitting droplet group 28 and the liquid film splitting droplet group 37; the collision of the liquid column splitting droplet group 28 and the liquid film 36; ) conflicts with the liquid film 36. For example, the collision with the liquid film 36 can also be considered as the micronization liquid column splits the droplet group 28 to be miniaturized, and the miniaturization of the droplet group is beneficial to the gas-liquid contact. However, it is not limited to the fact that the fine liquid droplet group of the secondary micronization is uniformly dispersed in the internal space 3, and if the fine liquid droplet group is not uniform, the gas-liquid contact becomes unfavorable instead, and desulfurization performance may be lowered.

The third suspense item is an increase in pressure loss. The portion generated by the interference will locally increase the density of the droplet group, and the increase in pressure loss will lead to an increase in power.

In this embodiment, in order to prevent the generation of the above-mentioned interference, the height of the atomizing nozzle 30 relative to the liquid column nozzle 20 is set so that the generation height of the liquid film splitting droplet group 37 generated from the liquid film 36 formed by the atomizing nozzle 30 is H5 is higher than the height H4 of the liquid column reaching portion 27 at the highest reaching height of the liquid column 26 formed by the liquid column nozzle 20 (H4<H5).

(Suppression of exhaust drift) Desulfurization performance in the case of a liquid-column absorption tower in which cleaning liquid is sprayed only by the liquid-column nozzle 20, where a mist eliminator is arranged horizontally in a vertical pipe (outlet pipe) extending upward from the interior space of the main body of the absorption tower High, a phenomenon in which the desulfurization performance is lowered when a mist eliminator is vertically arranged in a horizontal pipe (outlet pipe) extending horizontally from the upper part of the internal space of the absorption tower main body. The above phenomenon is due to the fact that the exhaust gas tends to flow obliquely from the inner space toward the outlet pipe, and the latter extends horizontally from the outlet pipe (easy to generate a biased flow). On the other hand, in this embodiment, the cleaning liquid is sprayed from the atomizing nozzle 30 on the downstream side (upper side) of the internal space 3 , so the exhaust to the outlet pipe 11 can be suppressed by the cleaning liquid sprayed from the atomizing nozzle 30 the bias current. Therefore, in addition to improving the desulfurization performance, an increase in the advective gas flow rate (smaller cross-sectional area of the tower) and an increase in dust removal performance can be expected.

As explained above, according to the present embodiment, compared with the liquid column type absorption tower or the atomization type absorption tower, the gas-liquid contact area 16 can be enlarged toward the circulation direction of the exhaust gas; 3. Generate liquid droplet groups with a wide particle size distribution; and the horizontal section of the inner space 3 at least suppresses and disperses the uneven distribution of the liquid droplet groups, which can improve desulfurization performance and dust removal performance.

And, the height of the atomizing nozzle 30 relative to the liquid column nozzle 20 is set so that the generation height H5 of the liquid film split droplet group 37 generated from the liquid film 36 of the atomizing nozzle 30 becomes higher than that of the liquid column formed by the liquid column nozzle 20. The height H4 of the liquid column reaching part 27 with the highest reaching height of 26 is higher, so the interference between the liquid droplets from the liquid column nozzle 20 and the droplets from the atomizing nozzle 30 can be suppressed, and the desulfurization performance and dust removal performance can be improved.

Also, for the liquid column type absorption tower, carry out the modification project of adding the atomizing nozzle 30 and the structure (atomizing head 31 and the second cleaning solution circulation line 32, etc.) for spraying the cleaning liquid from the atomizing nozzle 30, or for Atomization type absorption tower, adding liquid column nozzle 20 and the structure for spraying cleaning liquid from liquid column nozzle 20 (liquid column head 21 and first cleaning liquid circulation line 22, etc.) performance and dust removal performance.

(Second Embodiment) Next, a second embodiment of the present invention will be described with reference to FIGS. 5 and 6 . In the absorption tower 50 of the present embodiment, the slip-out preventing material 51 is provided on the absorption tower main body 2 of the first embodiment, and therefore the same reference numerals are assigned to the same configurations as those of the first embodiment, and descriptions thereof are omitted. Furthermore, among the configurations included in the absorption tower 1 of the first embodiment, the configurations not directly related to the present embodiment are omitted from illustration.

In the desulfurization device, desulfurization of the exhaust gas is carried out by gas-liquid contact with the cleaning liquid, so it is necessary to prevent the exhaust gas from contacting the absorption liquid so as to prevent the exhaust gas from sliding upward in the inner space 3 of the absorption tower 1 as much as possible. The wall edge (near the inner peripheral surface 7) of the absorption tower main body 2, or the part that becomes a corner (for example, the part of the four corners in the case of the peripheral wall 6 in the case of a rectangular tube) is a part where the slipping of the exhaust gas is likely to occur. In the present embodiment, in order to suppress the slipping of the exhaust gas, a slip-out preventing material 51 protruding from the inner peripheral surface 7 into the interior space 3 is provided on the peripheral edge portion of the internal space 3 where the slipping of the exhaust gas easily occurs (see Figure 5).

The height position where the slip-out prevention material 51 is installed is above the upper edge of the exhaust air inlet 8 and is at least a part of the height range 53 below the atomizing head 31 . For example, it is divided into a first area above the upper edge of the exhaust inlet 8 and a height range below the liquid column head 21, and a second area above the liquid column head 21 and below the height range of the atomizing head 31. In this case, the slip-out prevention material 51 may be provided only in one of the regions, or may be provided in both regions. In addition, a plurality of slip-out prevention materials may be provided in one region.

An example of the shape of the slip-out preventing material 51 is shown in (a)-(d) of FIG. 6 . (a) to (d) of FIG. 6 are cross-sectional views along the arrow VI-VI of FIG. 5 , and illustrations of the liquid column head 21 and the like are omitted. (a) to (c) are cases where the peripheral wall 6 is a rectangular cylinder, and (d) is a case where the peripheral wall 6 is a cylindrical shape. (a) is a triangular-shaped slip-out prevention material 51A that covers the four corners of the inner peripheral surface 7 of the peripheral wall 6, and (b) and (d) are the wall edges (inner peripheral) that cover the peripheral wall 6 across the entire circumference. The slide-out preventing materials 51B and 51D in the vicinity of the surface 7), (c) is the slide-out preventing material 51C combining (a) and (b).

According to this embodiment, since the slip-out preventing material 51 is provided on the outer peripheral portion of the internal space 3 where the slip-out of the exhaust gas easily occurs, the exhaust gas discharged from the absorption tower 50 can be reduced without contact with the cleaning liquid gas-liquid. It can further improve the desulfurization performance and dust removal performance.

In addition, the present invention is not limited to the above-mentioned embodiment and modifications described as an example, and various changes in design and the like can be made other than the above-mentioned embodiment and the like within the range not departing from the technical idea related to the present invention.

1,50: absorption tower 2: The main body of the absorption tower 3: Internal space 8: Exhaust inlet 9: Inlet pipe (exhaust introduction part) 10: Exhaust outlet 11: Outlet pipe (exhaust discharge part) 12: Mist eliminator 13: Liquid storage part (absorption tower tank) 14: Lower space 15: Upper space 16: Gas-liquid contact area 16A: The first gas-liquid contact area 16B: The second gas-liquid contact area 20: Liquid column nozzle 21: Liquid column head (liquid column tube) 22: The first cleaning liquid circulation line 23: 1st circulation piping 24: 1st circulation pump 25,35: valve 26: liquid column 27: Liquid column reaches the part (upper spray top) 28: Liquid column splitting droplet group 30: Atomizing nozzle 31: atomization head (atomization tube) 32: The second cleaning liquid circulation line 33: Second circulation piping 34: Second circulation pump 36: liquid film 37: liquid film split droplet group (atomization split droplet group) 51, 51A, 51B, 51C, 51D: slip-out prevention material D1: Droplet distribution of liquid column D2: Droplet distribution of atomization F: Flow direction of exhaust H1: The height of the liquid column nozzle H2: Height of atomizing nozzle H3: The height of the upper edge of the exhaust inlet H4: Height of the liquid column reaching part (the highest reaching height of the liquid column) H5: The generation height of liquid film splitting droplet group

[ Fig. 1] Fig. 1 is a sectional view showing a schematic configuration of an absorption tower according to a first embodiment of the present invention. [Fig. 2] It is a conceptual diagram of the droplet distribution of the liquid column and the droplet distribution of the atomization. [ Fig. 3 ] is a schematic diagram schematically showing dispersion of a liquid droplet group ejected from a liquid column nozzle and dispersion of a liquid droplet group ejected from an atomizing nozzle. [ Fig. 4 ] is a schematic diagram schematically showing the interference between a droplet group ejected from a liquid column nozzle and a droplet group ejected from an atomizing nozzle, (a) showing a state of interference, and (b) showing a state of no interference. [ Fig. 5] Fig. 5 is a sectional view showing a schematic configuration of an absorption tower according to a second embodiment of the present invention. [ Fig. 6] Fig. 6 is a cross-sectional view in the direction of arrow VI-VI in Fig. 5, showing an example of plural forms of the slip-out preventing material.

1: Absorption tower

2: The main body of the absorption tower

3: Internal space

4: bottom surface

5: Ceiling surface

6: Surrounding wall

7: Inner peripheral surface

8: Exhaust inlet

9: Inlet pipe (exhaust introduction part)

10: Exhaust outlet

11: Outlet pipe (exhaust discharge part)

12: Mist eliminator

13: Liquid storage part (absorption tower tank)

14: Lower space

15: Upper space

16: Gas-liquid contact area

16A: The first gas-liquid contact area

16B: The second gas-liquid contact area

20: Liquid column nozzle

21: Liquid column head (liquid column tube)

22: The first cleaning liquid circulation line

23: 1st circulation piping

24: 1st circulation pump

25: valve

26: liquid column

27: Liquid column reaches the part (upper spray top)

28: Liquid column splitting droplet group

30: Atomizing nozzle

31: atomization head (atomization tube)

32: The second cleaning liquid circulation line

33: Second circulation piping

34: Second circulation pump

35: valve

36: liquid film

37: liquid film split droplet group (atomization split droplet group)

F: Flow direction of exhaust

H1: The height of the liquid column nozzle

H2: Height of atomizing nozzle

H3: The height of the upper edge of the exhaust inlet

H4: Height of the liquid column reaching part (the highest reaching height of the liquid column)

Claims (2)

An absorption tower of a desulfurization device, which absorbs and removes sulfur oxides in exhaust gas with cleaning liquid, is characterized in that: the main body of the absorption tower has an internal space for exhaust gas to flow from the bottom to the top; a liquid column nozzle, It is installed in the above-mentioned internal space to spray the cleaning liquid upward in a liquid column shape; and the atomizing nozzle is arranged in the above-mentioned internal space above the above-mentioned liquid column nozzle to spray the cleaning liquid downward in a conical shape; The nozzle is a hollow cone nozzle with a circular spray pattern, and it is arranged at a height higher than the highest height of the liquid column formed by the cleaning liquid sprayed from the above-mentioned liquid column nozzle. The cleaning sprayed from the above-mentioned atomizing nozzle After the liquid is sprayed and then expanded into a liquid film, the liquid film is split into a group of liquid film split droplets as it falls. The generation height of the droplet group is lower than the height position, and the above-mentioned liquid column nozzle is a liquid column formed by the cleaning liquid sprayed from the above-mentioned liquid column nozzle, and is arranged in a liquid film that is not in contact with the cleaning liquid sprayed from the above-mentioned atomizing nozzle. At the height of the interference, the generation height of the liquid film splitting droplet group of the cleaning liquid sprayed from the atomizing nozzle is higher than the maximum reaching height of the liquid column formed by the cleaning liquid sprayed from the liquid column nozzle. As the absorption tower of the desulfurization device recorded in claim item 1, its Among them, an atomizing head that extends substantially horizontally in a manner that crosses the above-mentioned internal space, supports the above-mentioned atomizing nozzle, and supplies cleaning liquid to the above-mentioned atomizing nozzle is provided, and the above-mentioned absorption tower main body has a substantially vertical vertical cylindrical shape. A peripheral wall, the inner peripheral surface of the peripheral wall partitions the internal space, and the exhaust gas inlet is provided on the peripheral wall, and the upper end edge of the exhaust gas inlet is provided on the inner peripheral surface of the peripheral wall. In the above, at least a part of the height range below the atomizing head is provided with a slip-out preventing material protruding from the inner peripheral surface into the inner space.

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