JPH08206448A - Wet exhaust gas desulfurization equipment - Google Patents

Abstract

PURPOSE: To provide a wet exhaust gas desulfurization equipment increased in gas absorbing speed by simply increasing the gas-liquid contact area of liquid droplets of an absorbing soln. and efficiently stirring the interiors of the liquid droplets of the absorbing soln. during the flight of the liquid droplets of the absorbing soln. through an absorbing column. CONSTITUTION: The liquid droplets ejected from spray nozzles 6 are positively allowed to collide with each other. The liquid droplets of the absorbing soln. soon after ejection having a high flying speed are allowed to collide with each other to be finely pulverized to increase a gas-liquid contact area. Or, the interiors of the liquid droplets of the absorbing soln. are stirred and a gas absorbing speed is increased to absorb SO2 gas by sprayed liquid droplets and an SO2 dissolving layer is formed on the surfaces of the liquid droplets before liquid droplets are allowed to at least partially collide with each other.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wet flue gas desulfurization apparatus, and more particularly to spraying an absorbing liquid for absorbing sulfur oxides in exhaust gas.

[0002]

2. Description of the Related Art In a wet flue gas desulfurization system, a system in which an absorbing liquid is dispersed in a gas absorbing structure is widely adopted. Inside the absorption tower of a conventional wet flue gas desulfurization device, a large number of spray nozzles for finely absorbing and dispersing the absorbing liquid in the tower are arranged, and the directions of the axes of the injection holes of the nozzles are all fixed directions. It is arranged toward. The absorbing liquid sprayed from the spray nozzle becomes droplets, and the outer contour of the droplet group forms a conical jet fluid. The spray angle, which is the angle of spread of the absorbing liquid droplets immediately after jetting, varies depending on the shape of the spray nozzle, but among the spray stages having a plurality of stages in the absorption tower, the nozzles arranged in the same spray stage area are All have the same spray angle. The spray nozzles were arranged in the absorption tower such that the intervals between the nozzles were constant, and the intervals between the nozzles were such that the frequency of collision of droplets was considerably reduced.

Research on separation of droplets by collision of droplets is one.
N.N. Ashgriz and J.M. Y. The report (Coalescence an
dseparation in binary collisions of liquid drops)
From this, it can be seen that the droplets after collision are more easily separated as the number of We is larger. Diameter and We number was moving at speed V d, droplet density ρ is, the internal pressure due to the surface tension σ of the droplet has a dynamic pressure generated when the stop at the time of a collision ^{(ρV 2/2) (2σ} / It is a ratio to d). It is known that in the collision of equal-diameter droplets, coalescence does not occur in almost any collision when the We number is 100 or more. For this reason,
In order to increase the We number so that the droplets after collision are easily separated, it is necessary to increase the collision angle between the droplets and increase the value of the relative velocity V.

Regarding the miniaturization of the liquid when the fuel is discharged to the combustion chamber of the internal combustion engine, there are known JP-A 61-255264 and JP-A 2-37262. FIG. 21 and FIG. 2 show the experimental results of the miniaturization of the liquids due to the collision of the liquids.
It is shown in FIG. FIG. 21 shows the relationship between the collision angle between liquids when the spray pressure of the liquid is constant and the particle size of the liquid droplets formed by the liquids being atomized by the collision at that time. Further, FIG. 22 shows the relationship between the spray pressure of the liquid when the angle at which the liquid collides with the liquid is constant and the particle size of the liquid droplets formed by atomizing the liquid due to the collision at that time. .
These experimental results also show that the liquids are made into finer particles by the collision of the liquids, and the atomization is promoted as the collision angle becomes larger.

[0005]

Absorption rate dN / dt
Can be generally expressed by the following equation. dN / dt = K _G · a · ΔC (1) Here, K _G represents the ease of mass transfer of the target gas to the absorbing liquid. a is the contact area between the gas and the absorbing liquid, and ΔC represents the difference between the concentration in the gas and the concentration in the absorbing liquid in terms of the gas concentration of the target gas component.

As can be seen from this equation, the gas absorption rate dN / dt can be increased by increasing the contact area a between the gas and the absorbing liquid or the difference ΔC between the concentration in the gas and the concentration in the liquid. As a method of increasing the gas-liquid contact area a, it is effective to increase the surface area by making the absorbing liquid into finer droplets.

However, in the prior art, since the droplet diameter of the formed absorbing droplet group is determined by the structure of the spray nozzles that are selectively arranged, when a finer absorbing droplet group is to be formed. However, there is a problem in that the back pressure of the pump for spraying the absorbing solution must be increased, and a larger power cost is required for miniaturization. Further, in the past, even if the droplets collide with each other, the collision point is considerably far from the spray nozzle position, so that the flight speed of the droplet itself and the relative velocity with other droplets that collide with the droplet are large. Since the number of nozzles decreases, it cannot be said that the nozzle arrangement is effective for making droplets finer.

Another method for refining the absorbing liquid is disclosed in Japanese Patent Laid-Open No. Hei 5
There is a method described in Japanese Patent No. 137943. In this method, a collision body is arranged above the spray nozzle provided upward. According to this structure, it is possible to separate the absorbing liquid by causing the absorbing liquid to collide with the bottom of the collision body and form the absorbing liquid droplet group. However, since it is necessary to install a colliding body for colliding the liquid in the absorption tower,
The gas flow will be restricted. In addition, there is a problem that maintenance of the deteriorated collision body and removal of scale attached to the collision body are required.

In addition, in the research conducted by the inventors of the present invention, the results of experiments in which a sulfurous acid gas was absorbed in a calcium carbonate solution or water of an absorbing liquid droplet showed that the droplet was sprayed very early after being sprayed. The surface is covered with a dissolved layer of sulfurous acid gas,
It was found that although the absorption rate decreases, if the inside of the absorbing liquid droplets can be stirred during flight, ΔC in the formula (1) can be increased, and the absorption rate can be recovered. FIG. 19 shows how the mass transfer speed (SO ₂ absorption speed) V decreases as the drop time T of the droplets of the absorbing liquid increases. As a result, it can be seen that if the inside of the absorbing liquid droplets is agitated during the drop time Tx of the droplets when the mass transfer speed decreases, the absorbing speed recovers to the position shown by the broken line in FIG.
However, there is a problem that it is difficult to stir the inside of the absorbing liquid droplet during flight. 20 shows the relationship between the droplet flight speed and the We number at each collision angle when droplets having a diameter of 6 mm collide with each other.

The object of the present invention is (1) it is possible to easily increase the gas-liquid contact area of the absorbing liquid droplet, and (2) the absorbing liquid droplet inside the absorbing liquid droplet during flight in the absorption tower. It is an object of the present invention to provide a wet flue gas desulfurization apparatus which can efficiently stir the gas and increases the gas absorption rate by these (1) and (2). Another object of the present invention is to provide a wet flue gas desulfurization apparatus in which the desulfurization rate is increased by positively colliding the droplets ejected from the spray nozzle.

[0011]

The above objects of the present invention can be achieved by the following constitutions. That is, in the flue gas desulfurization device that processes the exhaust gas by gas-liquid contact between the spray droplets of the absorption liquid and the exhaust gas in an absorption tower equipped with a plurality of spray nozzles that spray the absorption liquid containing the desulfurizing agent from the injection holes, Wet flue gas desulfurization apparatus in which two or more spray nozzles having mutually different angles with the vertical direction of the spray direction are combined to cause collision of the absorbing liquid droplet groups sprayed from each of the spray nozzles. Is.

As a more specific configuration of the wet flue gas desulfurization apparatus of the present invention, (1) the entire region of the jet fluid formed by the droplet group of the absorbing liquid sprayed from the first spray nozzle is adjacent to each other. The first and second spray nozzles are arranged such that a part of the absorbing liquid droplet jet fluid sprayed from the second spray nozzle and the first spray nozzle overlap with each other within a height of 1.5 m from the injection hole of the first spray nozzle. At least one set is arranged, (2) A part of the jet fluid formed by the absorbing liquid droplet group having one nozzle hole of a pair of adjacent spray nozzles as an apex, and the jet of the other spray nozzle. The central axis of the nozzle hole of one spray nozzle intersects or twists the central axis of the nozzle hole of the other spray nozzle so that a part of the jet fluid formed by the absorbing liquid droplet group with the hole as the vertex overlaps. Place a pair of spray nozzles so that Configuration can be, and the like become Te.

In the configuration (2), a means for changing the intersecting angle between the central axis of the injection hole of one spray nozzle and the central axis of the injection hole of the other spray nozzle, for example, the injection hole of the spray nozzle is It is also possible to provide a pipe rotating means at the base of the absorption liquid supply pipe provided in plural in the longitudinal direction so as to make the direction of the injection hole of the spray nozzle variable.

Further, as a concrete constitution of the wet flue gas desulfurization apparatus of the present invention, (3) the absorption liquid is sprayed in an absorption tower provided with a plurality of spray nozzles for spraying the absorption liquid containing the desulfurization agent from the injection holes. In a flue gas desulfurization device that treats exhaust gas by contacting liquid droplets and exhaust gas in a gas-liquid manner, each spray nozzle is equipped with injection holes that spray the absorbing liquid in a circular ring pattern, and the spray angle of the absorbing liquid is relatively small. It is composed of a first spray nozzle having a hole and a second spray nozzle having a nozzle hole with a relatively large absorption liquid injection angle, and a second spray nozzle is provided on the upstream side of the exhaust gas flow with respect to the nozzle hole of the first spray nozzle. (4) An absorption tower having a spray nozzle for spraying an absorbing liquid containing a desulfurizing agent from the injection hole. Absorbed within In a flue gas desulfurization device for treating exhaust gas by contacting the spray droplets with exhaust gas in a gas-liquid manner, a spray nozzle provided with a spray hole for spraying the absorption liquid upward and a spray hole for spraying the absorption liquid downward were provided. It is possible to arrange at least one combination of spray nozzles and to make the absorbing liquid sprayed upward and the absorbing liquid sprayed downward collide with each other.

In the wet flue gas desulfurization apparatus of the present invention, the absorption liquid supply pipe having a plurality of spray nozzles in the longitudinal direction is arranged in the longitudinal direction so as to be substantially orthogonal to the flow direction of the exhaust gas. It can be configured.
Further, a liquid containing an oxidizing agent such as hydrogen peroxide may be sprayed from a part of the spray nozzles of the spray nozzle group.

[0016]

The present invention is to increase the gas-liquid contact area by colliding the absorbing liquid droplets with each other immediately after jetting with a high flight speed to make the droplets fine. Further, in the present invention, in order to agitate the inside of the absorbing liquid droplet and increase the gas absorption rate, the spray droplet absorbs SO ₂ gas and forms a dissolved layer of SO ₂ gas on the surface of the droplet. After that, at least a part of the droplets collides with each other.

In the present invention, the absorbing liquid is ejected from the two or more spray nozzle injection holes in the respective predetermined injection directions, and the jet fluids having the respective injection holes as apexes overlap in the absorption tower. Therefore, at least a part of the absorbing liquid droplets constituting each jet fluid collides, and the impact generated at that time causes atomization of the absorbing liquid droplets, increasing the surface area of the absorbing liquid droplets and increasing the surface area. Only the absorption rate of SO ₂ gas increases. Further, during this collision or atomization, the inside of the droplet is vigorously stirred and the SO ₃ concentration on the surface of the droplet is reduced to restore the absorption performance.

[0018]

Embodiments of the present invention will be described with reference to the drawings. Example 1 FIG. 1 is a schematic vertical cross-sectional view of an absorption tower 1 in which combustion exhaust gas is brought into contact with an absorption liquid composed of limestone slurry, showing a jet fluid formed by droplet groups of the absorption liquid sprayed from a spray nozzle 6. The spray nozzle 6 is arranged so that the entire area and a part of the absorbing liquid droplet jet fluid sprayed from another adjacent spray nozzle 6 overlap vertically within a distance of 1.5 m from the spray nozzle injection hole. 2 represents an ideal absorption tower of a wet desulfurization device.

FIG. 2 shows a cross-sectional view of the absorption tower 1, in which a supply pipe 4 extends from the main distribution pipe (header) 3 into the absorption tower 1. From the supply pipe 4, a spray nozzle pipe 5 is provided. Is branched in a direction orthogonal to the supply pipe 4. A spray nozzle 6 is attached to the tip of the spray nozzle pipe 5, and the injection hole of the spray nozzle 6 is directed vertically downward. Spray angle 9 as these spray nozzles 6
A hollow cone nozzle with a 0 ° spray pattern is used. A plurality of these spray nozzles 6 are provided at the same height for each stage, and the intervals between the spray nozzles 6 are 1.
It is set to 5m. This is shown schematically in FIG.
The interval between the spray nozzles 6 is set to 1.5 m, and the spray stages each including the spray nozzle 6 group are arranged in multiple stages in the absorption tower 1.

Boiler exhaust gas is supplied from a boiler exhaust gas inlet 10 provided on the lower side surface of the absorption tower 1,
It moves upward at a linear velocity of 2.86 m / s. Absorbing liquid droplets are sprayed from the spray nozzle 6 at an initial velocity of 11 m / s to the exhaust gas flow and come into countercurrent contact, and the sulfur oxides in the exhaust gas are absorbed by the absorbing liquid. It is discharged from the system from 11.

The sprayed absorbing liquid droplets form a jet fluid 7 having a conical outer shape. 1.5m between spray nozzles 6
Since the jet fluids 7 are arranged at intervals of, a region where they overlap each other after the point where they drop 0.75 m in the vertical direction from the nozzle injection hole is formed. Most of the absorbing liquid droplets have a diameter of about 0.6 mm, and they drop in flight in each direction, but the falling velocity is reduced by the exhaust gas flow rising from below. Therefore, when the absorbing liquid droplet having a diameter of about 0.6 mm reaches a point 1.5 m below the spray nozzle injection hole in the vertical direction, the flight speed is about 3 m / s. In the overlapping region of one jet fluid 7 and another jet fluid 7, the flying droplet collides with the flying droplet from the adjacent spray nozzle 6 for the first time. Since the angle of collision is about 90 °, the relative velocity of these droplets is 4.2 m / s or more.
The number is 161 or more (see FIG. 20). We number is 100
Since the droplets are much larger than the above, the droplets that have collided are separated and miniaturized after almost colliding at any contact position between the droplets to increase the surface area. Due to this increase in the surface area, the absorption rate of SO ₂ by the absorbing liquid droplets after collision is increased by about 14% as compared with the absorption tower provided with the spray nozzle having the structure of the conventional parallel spray system.

Embodiment 2 In this embodiment shown in FIG. 4 (a schematic vertical sectional view of the absorption tower 1), a supply pipe 4 extends horizontally in the absorption tower 1 from a header 3 for transporting an absorption liquid containing an alkaline solution. , The spray nozzle 6A and the spray nozzle 6 in the supply pipe 4 in the absorption tower 1.
B is joined. And the central axis 8 of the injection hole of the spray nozzle 6A and the central axis 8 of the injection hole of the spray nozzle 6B.
The spray nozzles 6A and 6B are arranged so that they intersect at least at one point in the absorption tower 1.

FIG. 5 (view of the cross section of the absorption tower 1) and FIG. 6 (header 3, supply pipe 4 and spray nozzle 6)
2), two supply pipes 4 connected to the header 3 are arranged in pairs so as to extend toward the inside of the absorption tower 1 from two opposite directions of the side walls of the absorption tower 1. .

FIG. 7 shows a view of the supply pipe 4 from the cross-sectional direction. The central axis 8 of the injection hole of the spray nozzle 6A joined to one of the paired supply pipes 4 is vertically downward. Direction is inclined at an angle of 30 °, and the other supply pipe 4
Center axis 8 of the injection hole of the spray nozzle 6B joined to
Is inclined at an angle of 30 ° in the direction opposite to the central axis 8 of the spray hole of the spray nozzle 6A from the vertically downward direction, and the central axis 8 of the spray hole of the spray nozzle 6A and the spray nozzle 6
The central axis 8 of the B injection hole has an angle θ (60 °) in the absorption tower.
The spray nozzle 6A and the spray nozzle 6B are arranged in a pair so as to intersect with each other. Spray nozzle 6
As shown in FIG. 8, A and 6B may be joined to the lower part of the supply pipe 4. In that case, spray nozzle 6A
The central axis line 8 of the injection hole and the central axis line 8 of the spray nozzle 6B are shown in FIG. 9 (a view from the sectional direction of the supply pipe 4).
Intersect as shown in.

The absorption liquid containing the alkaline solution is used in the absorption tower 1
It is transported by the pumping pump 2 from the absorbing liquid sump 9 at the bottom. The absorbing liquid passes through the header 3 and the supply pipe 4 and is sprayed by the spray nozzle 6A or the spray nozzle 6B to form a conical jet fluid 7 having the nozzle nozzle holes at the apexes. The jet speed of the absorbing liquid at this time is 11 m /
The spray angle of the absorbing solution is set to 30 ° in s. Part of the absorbing liquid droplets ejected from each spray nozzle injection hole has a maximum of 90 °.
The absorbing liquid droplets collide with each other at an angle of, and the absorbing liquid droplets are agitated inside due to the impact at the time of collision, and the absorbing liquid droplets become finer and the surface area increases.

Gas flow rate with SO ₂ concentration of 2000 ppm 2.
0.6m diameter in the pipe flowing from bottom to top at 86m / s
When m droplets are created and supplied at a jetting speed of 11 m / s, the droplets absorb SO ₂ gas after jetting, and a SO ₂ layer is formed on the droplet surface. Fall to. Therefore, in this case, the spray nozzles 6A and 6B are arranged such that the droplets are ejected and the absorbing liquid droplets collide with each other within 0.2 seconds. As a result, since the absorbing liquid droplets collide with each other, the absorbing liquid droplet contact surface and the inside of the droplet are mixed by utilizing the stirring caused by the collision. As a result, the SO ₂ concentration on the absorbent contact surface decreases, and at the same time, the impact due to collision causes atomization of the absorbent droplets, increasing the surface area and increasing the SO ₂ gas absorption amount.

FIG. 10 shows the relationship between the time elapsed after the absorption liquid is ejected from the spray nozzle 6 and the SO ₂ absorption amount (solid line in this embodiment, broken line in the prior art). If the droplet of the prior art is to obtain the SO ₂ absorption amount of 1.0 second after being jetted by this embodiment, it is found that about half of 0.5 seconds is sufficient.

Embodiment 3 This embodiment will be described as an improvement of Embodiment 2 above. As shown in FIG. 11, a rotating portion 14 surrounded by a box 12 is provided at the header 3 side base of the supply pipe 4 to which the spray nozzle 6 described with reference to FIGS.
The supply pipe 4 is rotated by the power of the motor 13. In this way, in this embodiment, the adjustment of the collision timing of the absorbing liquid droplets is performed by rotating the supply pipe 4 and changing the intersecting angle θ of the injection hole axis 8 of the spray nozzle 6 from the state shown in FIG. 12 to the state shown in FIG. 13, for example. By changing it, it is possible to change the collision timing of the absorbing liquid droplets ejected from each injection hole.

Embodiment 4 This embodiment is shown in FIG. 14 which is a schematic vertical sectional view of the inside of the absorption tower and FIG. 15 which is a perspective view of a component for spraying the absorbing liquid. In addition, Example 1
Each component having the same function as the component described in 1 above is assigned the same reference numeral and the description thereof is omitted. FIG. 14 shows an ideal spray nozzle arrangement relationship in which a spray nozzle 15 having a narrow absorption liquid spray angle and a spray nozzle 16 having a wide absorption liquid spray angle are combined.

A narrow-angle spray spray nozzle 15 is provided in the absorption tower 1, and a wide-angle spray spray nozzle 16 is arranged vertically below it.
Has been deployed. The narrow angle spray nozzle 15 has
The absorption liquid is supplied from the supply pipe 4, and a spray pattern in which the horizontal cross section of the absorption liquid droplet group is annular from the injection hole of the narrow-angle spray spray nozzle 15 (this is called a narrow-angle spray spray nozzle spray fluid 17). Form and spray. The absorbing liquid sprayed from the injection holes of the narrow-angle spray spray nozzle 15 is sprayed at a spray angle of about 30 °. The absorption liquid is supplied to the wide-angle spray spray nozzle 16 vertically below the narrow-angle spray spray nozzle 15 from the streamline supply pipe 19, and the absorption liquid sprayed from the injection hole of the wide-angle spray spray nozzle 16 has a spray angle of about 90 °.
To form a droplet group (referred to as a wide-angle spray spray nozzle jet fluid 18).

As shown in FIG. 15, the narrow-angle spray spray nozzle 15 and the wide-angle spray spray nozzle 16 vertically below the spray nozzle 15 are
It is a set of upper and lower, so that the narrow-angle spray spray nozzle jet fluid 17 and the wide-angle spray spray nozzle jet fluid 18 are
They will meet after collision zone 20.

Regarding the droplets themselves forming the jet fluid, the absorbing liquid droplets ejected from the narrow-angle spray nozzle 15 fall inside the absorption tower 1 while absorbing the sulfurous acid gas. A part of the absorbing liquid droplets contacts the streamline-type supply pipe 19, but the streamline-type supply pipe 19 has a streamline cross section, so that the collision of the absorbing liquid can be suppressed slightly, and after passing through the supply pipe 19. The influence on the spray pattern can be reduced. The absorbing liquid droplets collide with the absorbing liquid that falls while absorbing the sulfurous acid gas from the wide-angle spray nozzle 16 at the time of dropping, at a collision angle of 30.
Collide at °. The absorbing liquid droplets that collide with each other violently stir the inside of the liquid and reduce the concentration of the absorbing component of the exhaust gas on the surface of the absorbing liquid, so that the absorbing liquid droplets formed after the collision recover the sulfur dioxide gas absorbing ability. .

A gas having a SO ₂ concentration of 2000 ppm flowed from the bottom to the top at a flow rate of 2.86 m / s to a diameter of 0.
When supplied at the ejection speed 11m / s to make a 6mm droplet, the droplets absorb ejected after SO ₂ gas, SO ₂ on the droplet surface
Layer was formed, and the absorption performance dropped sharply in about 0.2 seconds. Therefore, the spray nozzle 1 is configured so that the absorbing liquid droplets collide with each other within 0.2 seconds after the wide-angle spray droplets are ejected.
5 and 16 are arranged. The narrow angle spray droplets collide with the wide angle spray droplets in about 0.4 seconds. As a result, the absorbing liquid droplets collide with each other, and the contact surface of the absorbing liquid droplets is mixed with the inside of the droplets by using the stirring caused by the collision, so that the SO ₂ concentration on the absorbing liquid contact surface is lowered, and at the same time, due to the collision. The impact causes atomization of the absorbing liquid droplets to increase the surface area, thereby increasing the absorption amount of SO ₂ gas. The solid line shown in FIG. 16 indicates the SO ₂ absorption amount when the droplets after jetting the absorbing liquid of this embodiment are made to collide with each other,
The broken line indicates the SO ₂ absorption amount when the droplets after ejecting the absorbing solution of the prior art are made to collide with each other. If it is attempted to obtain the SO ₂ absorption amount of 1.0 seconds after the ejection of droplets according to the prior art by this example, it is found that 0.6 seconds is sufficient.

Embodiment 5 This embodiment shows an improved example of the above Embodiment 4. In this embodiment, in the narrow-angle spray spray nozzles 15 and the wide-angle spray spray nozzles 16 arranged vertically below in the fourth embodiment shown in FIG. 15, hydrogen peroxide is supplied from the wide-angle spray spray nozzles 16 located below. Disperse the absorbing liquid containing. Therefore, the narrow-angle spray spray nozzle jet fluid 17 and the wide-angle spray spray nozzle jet fluid 18 partially intersect with each other after the collision ring region 20.

As a result, the absorbing liquid droplets contained in the narrow-angle spray spray nozzle jet fluid 17 are a fresh absorbing liquid just after spraying before the collision ring region 20, so that the SO ₂ gas absorption performance is high and the collision ring is high. In the region 20 and thereafter, the wide-angle spray nozzle 18 is mixed with the absorbing liquid containing hydrogen peroxide contained in the jet fluid 18, and the oxidizing power of this hydrogen peroxide causes SO 2
By changing ₃ to SO ₄ , the SO ₃ concentration of the droplet can be lowered and the SO ₂ gas absorption performance can be improved. For this reason,
The SO ₂ gas absorption performance of the absorption liquid can be improved, and the effective utilization region in the absorption tower can be expanded.

Example 6 FIG. 17 shows only a pair of the absorption liquid supply pipe 4 and the spray nozzle 6, which are the main parts in the absorption tower of this example. As shown in FIG. 17, a plurality of pairs of supply pipes 4 which are vertically arranged in two stages and horizontally extend in the absorption tower are arranged in the absorption tower. Spray nozzle 6 for spraying the absorbing liquid in a liquid column state
However, the upper supply pipe 4 is connected downward and the lower supply pipe 4 is connected upward. These spray nozzles 6,
The lower spray nozzle 6 is arranged vertically below the upper spray nozzle 6 so that the upper supply pipe 4 and the lower supply pipe 4 are paired one by one. Therefore, the absorbing liquid column sprayed from the lower spray nozzle 6 and the absorbing liquid column sprayed from the upper spray nozzle 6 collide between both spray nozzles 6, and the impact causes atomization of the absorbing liquid. It is carried out and dispersed in the absorption tower as absorbing liquid droplets.

FIG. 18 shows a method of making the absorbing liquid column smaller by the conventional method. According to this structure, it is possible to separate the absorbing liquid by causing the absorbing liquid ejected from the spray nozzle 6 to collide with the bottom of the collision body 21 to form the absorbing liquid droplet group. However, since the colliding body 21 for colliding the liquid has to be installed in the absorption tower, the gas flow is restricted. In addition, maintenance of the deteriorated collision body 21 and removal of slag adhering to the collision body 21 are required. However, if the liquid columns collide with each other as shown in FIG. 17, it is not necessary to provide the collision body 21 in order to make the absorbing liquid fine. Maintenance is simple and easy because there is no need for maintenance of the collision body and removal of slag adhering to the collision body.

[0038]

As is apparent from the above description, according to the method for dispersing an absorbent liquid in the absorbent structure according to the present invention, the absorbent can be sufficiently atomized and dispersed in the absorbent structure, and at the same time, the absorbent liquid can be dispersed. The internal agitation of the above is actively performed, and the gas absorption rate can be increased. By applying the above effect to the desulfurization device, it is possible to reduce the amount of circulating absorption, save the pump power cost accompanying it, and downsize the absorbing part.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a desulfurization apparatus absorption tower in which the absorbing liquid droplets of Example 1 of the present invention collide with each other at the initial stage of spraying.

FIG. 2 is a horizontal sectional view of FIG.

FIG. 3 is an explanatory diagram showing intervals of spray nozzles in FIG.

FIG. 4 is a cross-sectional view of a desulfurization apparatus absorption tower in which the central axis of the spray nozzle injection hole of Example 2 of the present invention is crossed.

5 is a horizontal sectional view of FIG.

FIG. 6 is a perspective view of a spray nozzle arrangement of the paired supply pipes in FIG.

7 is a cross-sectional view of a pair of supply pipes and a spray nozzle in FIG.

FIG. 8 is a diagram showing joining of a supply pipe and a spray nozzle according to a second embodiment of the present invention.

9 is a cross-sectional view of a pair of supply pipes and a spray nozzle in FIG.

FIG. 10: SO of collision droplet in Example 2 of the present invention
It is a figure which shows the increase of the absorption amount of ₂ .

FIG. 11 is a partial cross-sectional view of an angle changing mechanism of a rotating portion of a supply pipe according to a third embodiment of the present invention.

FIG. 12 is an explanatory diagram of changes in the absorbent intersecting angle from the spray nozzle according to the third embodiment of the present invention.

FIG. 13 is an explanatory diagram showing changes in the absorbent intersecting angle from the spray nozzle according to the third embodiment of the present invention.

FIG. 14 is a cross-sectional view of an absorption tower in which a narrow-angle spray nozzle is arranged at the upper part and a wide-angle spray nozzle is arranged at the lower part in Example 4 of the present invention.

FIG. 15 shows the narrow-angle spray nozzle at the top of FIG.
It is a perspective view of the piping which arranged the wide-angle spray nozzle in the lower part.

FIG. 16: SO of collision droplet in Example 4 of the present invention
It is a figure which shows the increase of the absorption amount of ₂ .

FIG. 17 is a principal part diagram of an absorption tower for colliding the absorbing liquid columns with each other to collide with the colliding object and refining the absorbing liquid according to the sixth embodiment of the present invention.

FIG. 18 is a principal part diagram of an absorption tower for refining the absorbing liquid by causing the absorbing liquid of the related art to collide with a colliding object.

FIG. 19 is a correlation diagram between the elapsed time after spraying the absorbing liquid droplets and the SO ₂ absorption rate.

FIG. 20 is a correlation diagram between droplet flight speed and We number at each collision angle when droplets having a diameter of 6 mm collide with each other.

FIG. 21 is a diagram showing a correlation between a collision angle between fuel liquids and a diameter of a fuel droplet formed.

FIG. 22 is a diagram showing a correlation between a pump pressure and a diameter of a fuel droplet formed when a collision angle of fuel liquids is 90 °.

[Explanation of symbols]

1 ... Absorption tower, 2 ... Pump, 3 ... Header, 4 ... Supply piping, 5 ... Spray nozzle piping, 6 ... Spray nozzle, 7
... absorption liquid droplet jet fluid, 8 ... injection hole central axis line, 9 ... absorption liquid liquid reservoir, 10 ... boiler exhaust gas inlet, 11 ... purified gas outlet, 12 ... box, 13 ... motor, 14 ... rotating part,
15 ... Narrow-angle spray spray nozzle, 16 ... Wide-angle spray spray nozzle, 17 ... Narrow-angle spray spray nozzle Jet fluid, 18
... Wide-angle spray spray nozzle jet fluid, 19 ... Streamline supply pipe, 20 ... Collision ring

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical display location B01D 53/34 ZAB (72) Inventor Akira Kato 7-1 Omika-cho, Hitachi-shi, Ibaraki Hitachi Ltd., Hitachi Research Laboratory (72) Inventor Hiroshi Miyadera, 7-1, 1-1 Omika-cho, Hitachi City, Ibaraki Prefecture Hitachi Ltd. Hitachi Research Laboratory (72) Inventor, Kotsu Shimazu 6-9 Takaracho, Kure City, Hiroshima Prefecture Babcock Hitachi Kure Factory

Claims (9)

[Claims] 1. A flue gas desulfurization apparatus for treating exhaust gas by gas-liquid contact between sprayed droplets of the absorption liquid and exhaust gas in an absorption tower equipped with a plurality of spray nozzles for spraying an absorption liquid containing a desulfurizing agent from injection holes. By combining two or more spray nozzles having mutually different angles with the vertical direction of the spray direction of the absorbing liquid, the absorbing liquid droplet groups sprayed from the spray nozzles are caused to collide with each other. Characteristic wet flue gas desulfurization equipment. 2. The whole area of the jet fluid formed by the droplet group of the absorbing liquid sprayed from the first spray nozzle is a part of the absorbing liquid droplet jet fluid sprayed from the adjacent second spray nozzle. And the height from the injection hole of the first spray nozzle is 1.5
2. The wet flue gas desulfurization apparatus according to claim 1, wherein at least one set of the first and second spray nozzles is arranged so as to overlap each other within m. 3. A part of the jet fluid formed by the absorbing liquid droplet group having the apex of one spray hole of a pair of adjacent spray nozzles and the jet hole of the other spray nozzle as a peak. In order that a part of the jet fluid formed by the absorbing liquid droplet group may overlap, the central axis of the spray hole of one spray nozzle and the central axis of the spray hole of the other spray nozzle intersect or twist. The wet flue gas desulfurization apparatus according to claim 1 or 2, wherein a spray nozzle is arranged. 4. The wet flue gas exhaust system according to claim 3, further comprising means for varying an intersecting angle between a central axis of the spray hole of one spray nozzle and a central axis of the spray hole of the other spray nozzle. Desulfurization equipment. 5. The direction of the spray hole of the spray nozzle is made variable by providing a pipe rotating means at the base of an absorbent supply pipe having a plurality of spray nozzle holes in the longitudinal direction thereof. 4. The wet flue gas desulfurization apparatus according to 4. 6. A flue gas desulfurization apparatus for treating exhaust gas by gas-liquid contact between sprayed droplets of the absorption liquid and exhaust gas in an absorption tower equipped with a plurality of spray nozzles for spraying an absorption liquid containing a desulfurizing agent from injection holes. , Each of the spray nozzles has injection holes for spraying the absorbing liquid in a ring-shaped pattern, and the first spray nozzle having injection holes having a relatively small absorbing liquid injection angle and the injection nozzle having a relatively large absorbing liquid injection angle. Consisting of a second spray nozzle provided with holes, the injection hole of the second spray nozzle is arranged on the upstream side of the exhaust gas flow with respect to the injection hole of the first spray nozzle,
2. The wet flue gas desulfurization apparatus according to claim 1, wherein at least one combination of these two spray nozzles is arranged. 7. A flue gas desulfurization device for treating exhaust gas by gas-liquid contact between sprayed droplets of the absorption liquid and exhaust gas in an absorption tower equipped with a spray nozzle for spraying an absorption liquid containing a desulfurizing agent from a nozzle hole, At least one combination of a spray nozzle having a spray hole for spraying the absorbing liquid upward and a spray nozzle having a spray hole for spraying the absorbing liquid downward is arranged, and the absorbing liquid sprayed upward and downward. A wet flue gas desulfurization device, characterized in that the sprayed absorbing liquid collides with each other. 8. The spray nozzle is provided with a plurality of injection holes in the longitudinal direction, and the absorption liquid supply pipe is arranged in the longitudinal direction so as to be substantially orthogonal to the flow direction of the exhaust gas. The wet flue gas desulfurization apparatus according to any one of 1. 9. The wet flue gas desulfurization apparatus according to any one of claims 1 to 8, wherein a liquid containing an oxidizing agent such as hydrogen peroxide is sprayed from a part of the spray nozzles of the spray nozzle group. Wet flue gas desulfurization equipment.