JP3349158B2 - Wet gas processing equipment - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a wet gas treatment method and apparatus for removing harmful components and other target components from exhaust gas, and particularly to a gas-liquid contact between an absorbent and a combustion exhaust gas such as coal or heavy oil. The present invention relates to an effective wet gas processing method and apparatus.

BACKGROUND ART Conventionally, various types of gas-liquid contact devices have been used as wet flue gas desulfurization devices for removing harmful substances such as sulfurous acid gas from flue gas such as coal-fired boilers. As one form, there is known a so-called liquid column type device such as Japanese Utility Model Laid-Open No. 59-53828 proposed by the present applicant.

This device ejects an absorbent such as lime slurry upward from a plurality of nozzles arranged in the absorption tower to form a form like a liquid column, and smoke is discharged in the ejected flow. By ventilating, it absorbs sulfurous acid gas contained in the flue gas and effectively removes dust such as fly ash.

The basic configuration thereof is as shown in the schematic diagram of FIG. 24 (A), where a smoke exhaust outlet 8 is provided above the absorption tower 2 and a smoke exhaust inlet 3 serving as an inlet of the exhaust gas 1 is provided below. In addition, a plurality of header pipes 190 are arranged in a lower row in the absorption tower 2, and a plurality of upward nozzles 4 shown in FIG.

The lower part of the absorption tower 2 is formed as a funnel-shaped liquid storage part 56 for storing the absorption liquid 5 such as lime slurry, and the recovery pump 21a.
Is returned to the absorption liquid storage tank 57 via the. The refluxed absorbing liquid 5 is again introduced into the upward nozzle 4 through the jet pump 21b, the flow opening / closing valve 60, and the header pipe 190.

The nozzle group consisting of the plurality of upward nozzles 4 arranged in the matrix form the liquid column-shaped jet 5a with the absorption liquid 5 directed upward, and at the same time, is introduced from the smoke exhaust introduction section 3 to the top of the tower. The exhaust gas 1 to be ventilated rises while accompanying the jet-like absorbing liquid 5 at the flow velocity, and passes through the jet 5a diverging like an umbrella at the top of the exhaust gas 1, thereby achieving gas-liquid contact.

Thereafter, the absorbent 5 entrained in the exhaust gas 1 is separated by a mist eliminator 6 provided above the absorption tower 2 near the top of the jet, and is collected in the absorbent storage tank 57. Further, the absorbing liquid 5 that falls directly into the liquid reservoir 56 is sent to the absorbing liquid storage tank 57 by the recovery pump 21a.

In the gas-liquid contact device having such a configuration, the pump 21b
Is operated to inject the absorbing liquid 5 upward from the upward nozzle 4 through the flow opening / closing valve 60 and the header pipe 190, and the exhaust gas 1 introduced from the side of the smoke exhaust section 3 passes through the jet stream 5a. By doing so, gas-liquid contact is achieved, and the treated exhaust gas (purified gas) 7 from which the sulfurous acid gas and the like have been removed is led out from the upper smoke exhaust outlet 8.

In the technique in which the absorbing liquid 5 is ejected upward as described above, not only gas-liquid contact is achieved for a long time when the absorbing liquid 5 reciprocates (up and down), but also reaches the top and forms an umbrella. When flowing down, the absorbing liquid 5 is in the form of droplets, so that the gas-liquid contact effect increases. When the amount of sulfurous acid gas or the like contained in the exhaust gas is small, the height of the liquid column can be changed. Operation is possible, and moreover, for example, as compared with a so-called packing method in which the absorbing liquid flows down into a column filled with a grid-like grid and comes into contact with gas, it is more difficult for the fluid passage to be clogged. Has advantages.

Further, in the case of the above technique, the injection pump 21b is operated to cause the absorption liquid 5 stored in the liquid storage section 56 and the absorption liquid storage tank 57 to be absorbed.
Is circulated to the header pipe 190 side, and the ejection pressure is set such that the absorption liquid 5 can be ejected from the nozzle 4 to a predetermined height.

In this figure, the injection pump 21b is represented by a single member for simplicity of description, but in actuality, a plurality of injection pumps 21b are used, so that the apparatus is compact, and equipment costs and operation costs are reduced. There is a problem from.

Further, in order to increase the efficiency of gas-liquid contact between the exhaust gas and the absorbing liquid, it is necessary to provide a number of nozzles for atomizing the absorbing liquid in contact with the exhaust gas.
As shown in the figure, there are also problems such as an increase in equipment load, such as the necessity of a plurality of nozzle groups for ejecting the absorbing liquid arranged in a matrix.

For this purpose, for example, in DE-A-1769945 or JP-A-9-507792, a tank for storing a slurry to be supplied and circulated to the nozzle is provided, and the liquid level of the tank is set higher than the nozzle ejection position. The gas absorbed with the absorbing liquid from the nozzle is separated from the gas at the upper part of the absorption tower, and the separated absorbing liquid is held in a tank. The liquid is ejected, and the ejection and circulation of the slurry liquid from the nozzle are enabled by utilizing the gravity difference without using the injection pump.

However, in this conventional technique, the condition is that the liquid level of the tank storing the absorbing liquid is at a position higher than the nozzle ejection position in the absorbing tower, but usually the absorbing tower has a considerable height. Setting the liquid level at a higher position has the disadvantage that the height of the tank is necessarily increased.

Further, in a gas cleaning apparatus such as a flue gas desulfurization apparatus, a load of a gas generation source such as a boiler generally fluctuates. Therefore, in any of the above apparatuses, when the gas flow rate is reduced, the gas flow rate is reduced. Gas cannot be brought into contact with the gas stream smoothly, sulfur dioxide gas and dust contained in the flue gas cannot be removed effectively, but also the absorption liquid cannot be removed at the top of the absorption tower. Can not be recovered, in other words, it becomes difficult to circulate the absorbent to the tank, and as a result, the tank liquid level gradually decreases, and eventually it becomes difficult to circulate the absorbent by its own weight. Was.

Further, in any of the above devices, the blowing speed of the absorbing liquid, in other words, the blowing height increases and decreases in proportion to the flow rate of the exhaust gas, and therefore, as shown in FIG. T ₁ or as shutdown T _2, the combustion capacity of the burner side is small, the exhaust gas flow rate decreases, it becomes impossible to lift the upflow height of the absorption liquid is ejected from the nozzle above the reference level As a result, substantially the entire amount of the jet flow falls into the liquid storage portion in a falling state without reaching the mist eliminator provided at the top of the tower, and the absorption liquid stored in the liquid storage portion becomes uselessly increased.

For this reason, in the conventional apparatus, in order to enable continuous circulation of the absorption liquid, the size of the liquid reservoir 56 is increased or the recovery pump 21a for reflux is set only when the absorption tower 2 starts up and shuts down. Correspondingly, a large capacity is prepared, but this leads to an unnecessary increase in equipment cost.

Further, the mist (droplet) which absorbed the target component such as sulfur dioxide gas accompanying the exhaust gas in each of the above devices collides with the bent plate of the mist eliminator on the upper part of the absorption tower and drops into the absorption tower to continuously circulate the absorption liquid. However, in the conventional apparatus as described above, the gas flow rate in the tower is usually 4 to 5 m / s
It is possible to catch the mist eliminator if it is of the order of magnitude, but in recent years there has been a demand for higher speeds such as increasing the gas flow rate in the tower to 5.5 m / s or more, for example, in order to improve processing capacity and save space. .

When the gas velocity is set to 5.5 m / s or more in this way, the mist eliminator will not be able to sufficiently remove the droplets that have reached that part, and the absorbed droplets will be discharged out of the tower together with the accompanying gas. It is not preferable not only to release to the atmosphere, but also to sending to the subsequent processing equipment.

At a gas flow rate of 5.5 m / s or more, the amount of the absorbing liquid that reaches the mist eliminator accompanying the gas greatly increases. A phenomenon in which droplets stay in a spiral shape at the entrance (scattered absorption liquid pool zone)
And mist removal performance is significantly reduced. This decrease in the mist removal performance is caused by the mist (droplets) being scattered again by the exhaust gas from the scatter absorbing liquid pool zone, and the escape of the mist from the exhaust flue is increased. .

DISCLOSURE OF THE INVENTION The present invention has been made in view of the drawbacks of the prior art, and has been made of an invention relating to wet gas treatment that enables smooth recovery of an absorbent without using an injection pump and even when the gas flow rate accompanying the absorbent is reduced. The purpose is to provide.

Another object of the present invention is an energy-saving method that does not require a large power, and achieves a cost reduction by eliminating an increase in the facility load of the nozzle, and also enables more efficient gas-liquid contact. It is an object of the present invention to provide an invention relating to wet gas treatment.

Another object of the present invention is to provide an invention relating to a wet exhaust gas treatment that can effectively solve the problem that occurs when the flow rate of the exhaust gas is reduced without unnecessarily increasing the size of the liquid reservoir and the pump capacity. With the goal.

In order to solve such a problem, the present invention provides a method as set forth in claim 1, wherein an absorbing liquid stored in an absorbing liquid storage section is jetted upward from a nozzle portion in an absorption tower, and the jet flow is converted into the absorption tower. In a wet gas processing apparatus for bringing a gas into a gas-liquid contact with an exhaust gas passing therethrough to absorb and remove a target component in the exhaust gas, the pressurized tank for generating a pressurized gas in a space above a surface of the stored liquid by using the absorbent liquid storage section Formed on the other hand, a recovery unit for recovering the absorption liquid having absorbed the target component is disposed at a predetermined position in the absorption tower higher than the stored liquid level in the pressurized tank, and closer to the pressurized tank side than the recovery unit. An outlet end opening of the communication pipe for refluxing the absorbing liquid is located in the storage liquid in the pressurized tank.

In this case, it is preferable that the urging pressure of the pressurized gas in the pressurized tank is used so that the absorbent stored in the pressurized tank can be jetted upward from the nozzle in the absorber. Also, when one of the target components to be absorbed and removed by the absorbing solution is sulfur dioxide (SO ₂ ), the pressurized gas is an oxygen-containing gas, and the oxygen-containing gas is removed from the bottom of the pressurized tank. It is good to blow into the stored liquid.

Therefore, according to this invention, the amount of the ejected absorbing liquid from the nozzle is determined by the pressure receiving area of the pressurized tank and the pressure of the pressurized gas, and the gas flow rate in the absorbing tower is changed by a load fluctuation of a combustion device such as a boiler. Even if the pressure fluctuates, the height of the jet of the absorbing liquid from the nozzle can be maintained almost constant by controlling the pressure in the pressurized tank in a direction to compensate for the fluctuation. This makes it possible to smoothly recover the absorbing liquid even when the flowing gas velocity decreases.

The gas pressure in the pressurized tank is adjusted so that the discharge amount of the suction liquid from the tank, the supply amount of the absorbing liquid to the tank, and the gas blowing amount into the tank are balanced to a predetermined pressure. Controlled.

Further, according to the present invention, instead of directly pumping the absorbent as in the case of the injection pump, the inside of the pressurized dunk is pressurized with pressurized gas such as compressed air. Without using a pressurized tank and only a gas compression source such as an air compressor that feeds pressurized gas to it,
It is possible to reduce the size of the device, reduce equipment costs and operating costs, and the like.

Further, in an apparatus using an upward nozzle in which the absorption liquid supply nozzle is upward, it is not necessary to position the upward nozzle above the liquid level of the pressurized tank. Can be.

Further, according to the present invention, when one target component to be absorbed / removed by the absorbing liquid is sulfur dioxide (SO ₂ ), the pressurized gas is an oxygen-containing gas, and the oxygen-containing gas is stored in a pressurized tank. It is good to blow into the bottom liquid.

This allows the slurry-containing liquid containing limestone, which has been jetted from the nozzle and absorbed SO ₂ by gas-liquid contact with the exhaust gas, to be stored in the pressurized tank when contacted with the oxygen-containing gas.
SO ₂ can be oxidized to form calcium sulfate dihydrate (gypsum).

Further, according to the present invention, the absorbing solution having absorbed / removed the target component is recovered to the pressurized tank side via the recovering section, and the absorbing solution can be circulated and reused.

When a communicating pipe for collecting the absorbing liquid from the collecting section is opened in the upper closed space inside the pressurized tank, the gas pressure in the space escapes into the absorption tower through the communicating pipe and functions as a pressurized tank. Cannot be maintained.

In view of this, the present invention is directed to a method in which the outlet end opening of the communication pipe for returning the absorbing liquid from the recovery section to the pressurized tank side is located in the storage liquid in the pressurized tank, so that the liquid is absorbed by the absorbing liquid in the communicating pipe. The gas pressure seal of the pressure tank is enabled, and the recovery unit is disposed at a predetermined position in the absorption tower higher than the liquid level in the pressurized tank. The liquid level in the communication pipe rises to a position balanced with the pressure inside the tank. By setting the height difference of the communication pipe, the position of the recovery section, and the tank internal pressure so that the liquid level in the communication pipe is lower than the position of the recovery section, the absorption liquid can be circulated from the recovery apparatus into the pressurized tank. The gas pressure sealing of the pressurized tank is made possible by the absorbing liquid in the communicating pipe.

According to the present invention, even if the absorbent is jetted upward in the absorption tower and the absorption liquid is collected in the collection section provided at the top of the absorption tower, the absorption liquid is partially dropped to the bottom of the absorption tower. Since the recovery section alone cannot recover 100%, it is preferable to use a low-pressure pump to return the liquid collected in the bottom of the absorption tower to the pressurized tank when the level of the liquid exceeds a predetermined amount. In addition, since a part of the liquid inevitably escapes together with the gas, replenishment is performed through the raw material supply pipe.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic view showing a wet gas processing apparatus according to an embodiment of the present invention.

FIG. 2 shows the gas flow rate in the gas processing apparatus of FIG.
FIG. 9 is a graph showing an example of acquiring a relationship between SO ₂ removal rates.

FIG. 3 is a schematic configuration diagram of a wet gas processing apparatus of an absorption liquid gravity supply type according to a first related invention of the present invention.

FIG. 4 shows an arrangement example of the trough-shaped absorbing liquid pipe of FIG. 3,
(A) shows streamlines in the case of one-stage horizontal arrangement, and (B) shows streamlines in the case of two-stage staggered arrangement.

FIG. 5 is a partial perspective view showing the arrangement state of the gutter-shaped absorbing liquid pipe and the flowing state of the absorbing liquid in FIG. 4 (A). FIG. (B) shows a case in which a notch is provided on the upper surface of the side wall of the trough-shaped absorption liquid pipe.

FIG. 6 shows an example in which, unlike the trough-shaped absorbing liquid pipe shown in FIG.
(A) is a semicircular tubular member having a circular cross section on the lower surface of the absorbent tube,
(B) shows the use of the tubular member 1 having a hollow circular cross section;
(C) uses a tubular member having an elliptical cross section, (D)
(E) has a number of small holes formed along the axial direction on the side facing the gap on both side walls, and (E) shows intermittently extending along the axial direction on the side facing the gap on both side walls. 2 shows a configuration in which a slit opening is formed.

FIG. 7 is a schematic view showing a wet gas processing apparatus according to a second related invention of the present invention.

FIG. 8 is a schematic view of a main part showing a wet gas processing apparatus according to a first modification of the dividing plate of FIG.

FIG. 9 is a schematic view of a main part showing a wet gas processing apparatus according to a second modification of the dividing plate of FIG.

FIG. 10 is a schematic view of a main part showing a wet gas processing apparatus according to a third modification of the dividing plate of FIG.

FIG. 11 is a schematic view of a main part showing a wet gas processing apparatus according to a fourth modification of the dividing plate of FIG.

FIG. 12 is a schematic diagram showing a configuration of a wet exhaust gas treatment apparatus according to a third related invention of the present invention.

FIG. 13 is a graph showing changes in the exhaust gas tower speed with respect to the operation time of the boiler.

FIG. 14 shows an exhaust gas treatment system according to a fourth related invention of the present invention, in which a wet absorption tower is interposed in a main path connecting an exhaust gas emission source and an atmospheric emission section, and (A) shows the startup of the absorption tower. Opening and closing state of the damper and the flow of exhaust gas before,
(B) is a diagram showing the opening / closing state of the damper and the flow of exhaust gas when the flow velocity of the exhaust gas introduced into the absorption tower from the boiler is equal to or higher than the loading flow velocity.

FIG. 15 is a schematic diagram showing an exhaust gas treatment system according to a modification of the invention shown in FIG. 14 in which a dividing plate for regulating the width of the exhaust gas flow path is provided in the absorption tower.

FIG. 16 is a schematic diagram showing an exhaust gas treatment system according to another modified example of the invention shown in FIG. 14 in which a dividing plate for regulating the width of the exhaust gas passage is provided in the absorption tower.

FIG. 17 is a schematic configuration diagram of a conventional exhaust gas absorption system in which a wet absorption tower is interposed in a main path connecting an exhaust gas discharge source and an atmospheric emission section.

FIG. 18 is a front view showing an outline of a wet exhaust gas treatment apparatus according to a fifth related invention of the present invention.

 FIG. 19 is a side view of FIG.

FIG. 20 is an enlarged partial perspective view of the mist eliminator mounted on the apparatus of FIG.

FIG. 21 is a front view showing an outline of a wet exhaust gas treatment apparatus according to a modification of the invention shown in FIG.

FIG. 22 is a logarithmic graph showing test results on the relationship between the gas flow rate in the tower and the mist concentration at the outlet of the mist eliminator in order to explain the invention of FIG.

FIG. 23 is a graph showing the test results on the relationship between the gas flow rate in the tower and the mist scattering rate at the inlet of the mist eliminator in order to explain the invention of FIG.

FIG. 24 (A) is a view schematically showing a configuration of a conventional wet gas absorption tower, and FIG. 24 (B) is a perspective view showing an upward nozzle group used in FIG.

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be illustratively described in detail with reference to the drawings. However, unless otherwise specified, the dimensions, materials, shapes, relative arrangements, and the like of the components described in this embodiment are not intended to limit the scope of the present invention, but are merely illustrative examples. Not just.

FIG. 1 is a schematic view showing a wet gas processing apparatus according to a first embodiment of the present invention.

In FIG. 1, an exhaust gas 1 from a combustion device such as a boiler is introduced into a flue gas introduction section 3 installed at a lower portion of an absorption tower 2. The introduced exhaust gas 1 comes into contact with the absorption liquid 5 supplied from the absorption liquid supply nozzle 4 installed in the lower part of the absorption tower 2, and the target component in the gas moves from the gas to the absorption liquid 5.

At this time, the combination of the target component and the absorbing solution in the gas is
It refers to those in which the target component is soluble in the absorbing solution, dust, and the like. For example, in this embodiment, the target component soluble in the absorbing solution is sulfur dioxide (SO ₂ ), and the absorbing solution used was a slurry containing limestone as an absorbing agent.

The nozzle is an upward nozzle 4 in the present embodiment, and the exhaust gas 1 introduced from the flue gas introduction section 3 is ejected from the nozzle 4 by injecting the absorbent 5 upward from the upward nozzle 4. Absorbed liquid jet 5a
The liquid is passed through the jet flow of the absorbing liquid 5 while bringing the gas into contact with the liquid, thereby achieving gas-liquid contact.

A mist eliminator 6 is disposed above the absorption tower 2 near the top of the jet, and the mist eliminator 6 removes the absorbing liquid 5 accompanying the gas 1.

The purifying gas 7 from which the target component is removed by the absorbing liquid 5 in the absorbing tower 2 and the absorbing liquid 5 entrained by the mist eliminator 6 is finally removed from the smoke exhausting section 8 to the atmosphere or after the necessary unillustrated Sent to the flow equipment.

On the other hand, a collecting device 9 having an upper side opened is disposed on the inner periphery of the side wall of the absorption tower 2 below the mist eliminator 6, and the absorbing liquid 5 captured by the mist eliminator 6 is collected by the collecting device 9, Through the pressure tank 11.

Therefore, the absorbing liquid 5 ejected from the absorbing liquid supply nozzle 4
The pressure of the pressurized tank 11 is set so that the height is raised by the flow velocity of the exhaust gas 1 and rises to a position higher than the collecting device 9.

The upper end of the communication pipe 10 is opened at the bottom of the recovery unit 9, and the lower end of the communication pipe 10 is opened at a position where it is always submerged in the absorbent 5 in the tank 11 from the upper surface of the pressurized tank 11. The gas sealing of the pressurized tank 11 is performed by 10.

That is, the absorbent 5 recovered by the recovery device 9 is connected to the communication pipe 10.
From the pressure tank 11 at this time.
A gas pressure of compressed air is applied to the inner upper closed space 11a, so that the absorbing liquid 5 in the pressurized tank 11 flows backward, and the communication pipe 10 is located at a position balanced with the pressure in the pressurized tank 11. Will rise. And the communication pipe
Communication pipe so that the liquid level in 10 is lower than the position of recovery unit 9
By setting the height difference of 10, the position of the collecting device 9 and the pressure in the tank 11, the absorbing liquid 5 in the communication pipe 10 can be circulated from the collecting device 9 while the absorbing liquid 5 is circulated from the collecting device 9 into the pressurizing tank 11. Enables 11 gas pressure seals.

A gas blowing pipe 13 connected to an air compressor 12 is installed at the bottom of the pressurized tank 11, and pressurized air, in other words, an oxygen-containing gas, is blown into the stored liquid.

This pressurized gas has two roles. The first is a pressurized tank 11
The second is to maintain the pressure in the inner upper closed space 11a. The second is that the slurry absorbing liquid 5 containing limestone that has absorbed SO ₂ by the gas-liquid contact oxidizes SO ₂ by contact with the oxygen-containing gas to form calcium sulfate 2. It is to produce a hydrate (gypsum).

The absorbent 5 stored in the pressurized tank 11
The absorption tower 2 is controlled via the absorption liquid supply pipe 14 and the flow control valve 15 for controlling the supply flow rate of the absorption liquid 5 by the pressure of the inner upper closed space 11a.
The liquid is circulated to the absorption liquid supply nozzle 4 in the inside.

 Next, the configuration of the pressurized tank 11 will be described.

At the top of the pressurized tank 11, an atmosphere opening pipe 17 and the tank 11
A pressure control valve 16 for controlling the internal pressure, a raw material supply pipe 18 for supplying a raw material such as a neutralizing agent on the side wall of the tank, and a liquid reservoir provided at the bottom of the absorption tower 2 by a drain recovery pump 21
Drain recovery pipe 20 for recovering absorbent 5 from 56
But they are attached respectively.

On the other hand, an extraction pipe 19 for extracting gypsum or the like generated by the oxidation of SO ₂ is attached to the bottom of the tank 11.

The reason why the pressurized tank 11 is configured as described above is as follows.

According to the present embodiment, even if the absorbent 5 is jetted upward in the absorption tower 2 and the absorption liquid 5 is recovered by the recovery unit 9 provided above the absorption tower 2, a part of the absorption liquid 5 is inevitably formed. Since it escapes together with the gas or a part of the gas falls to the bottom of the absorption tower 2, 100% of the gas cannot be recovered by the recovery device 9 alone. Therefore, when the level of the liquid accumulated at the bottom of the absorption tower 2 becomes equal to or more than a predetermined amount, the liquid is returned to the pressurized tank 11 by the pump 21.

In addition, a neutralizing agent and the like are supplied to the pressurized tank 11 from a raw material supply pipe 18, and a part is extracted by an extraction pipe 19 and is sent to a gypsum recovery step. Therefore, in the present embodiment, the liquid level of the pressurized tank 11 is maintained by balancing the supply of the absorbent through the raw material supply pipe 18 and the amount of the liquid withdrawn to the gypsum recovery step (not shown) and the amount of the liquid with the gas. I have.

The amount of air supplied from the air compressor 12 into the pressurized tank 11 is blown according to the amount of SO ₂ contained in the exhaust gas 1.
Therefore, the air pressure in the pressurized tank 11
14 and the discharge amount of the absorbing liquid by the extraction pipe 19 and the communication pipe 10,
Control is performed so that the supply amount of the absorbing liquid by the raw material supply pipe 18 and the drain recovery pipe 20 and the amount of the gas blown by the air compressor 12 are balanced to be a predetermined pressure.

In the case where the above-mentioned balance is lost and the pressure in the tank becomes higher than a predetermined pressure, the pressure control valve 16 is automatically opened, the pressure in the tank is released until the pressure returns to the predetermined pressure, and the pressure in the tank is reduced to the predetermined pressure. maintain.

Next, the effect of the apparatus shown in the above embodiment was confirmed by the following experiment.

FIG. 2 is a graph showing an example in which, in the gas treatment apparatus of the present invention, the absorption liquid is a slurry containing calcium carbonate, and the relationship between the gas flow rate and the removal rate of SO ₂ is obtained while keeping the circulation flow rate of the absorption liquid constant. .

This experiment shows that a performance of 90% or more, which is generally required as a sulfur dioxide removal rate, is obtained in a wide range of gas flow rates.

Therefore, even when the load of the gas generation source such as a boiler fluctuates and the gas flow rate decreases, the sulfur dioxide can be removed with an efficiency of 90% or more.

In this experiment, almost all of the absorbing liquid could be recovered by the recovery device 9 having the upward opening shown in FIG. 1, and the operation could be performed smoothly. Further, even under the condition where the gas flow velocity is reduced, the pressure of the pressurized tank 11 is increased to increase the absorption liquid 5.
The absorption liquid 5 was almost completely recovered from the recovery device 9 even in this case.

Therefore, according to this embodiment, the absorption liquid can be smoothly recovered without using the injection pump and even when the gas flow rate accompanying the absorption liquid decreases.

In particular, according to the present embodiment, by pressurizing the inside of the pressurized tank with a pressurized gas such as compressed air, the liquid level of the pressurized tank does not need to be located above the absorption liquid supply nozzle, and the pressurized tank is In addition to being able to be lowered, free arrangement is possible. Further, as described above, even when the gas flow rate in the absorption tower 2 is reduced due to a load fluctuation and the like, and the absorbing liquid 5 cannot be entrained, the pressure in the pressurized tank is increased and the absorbing liquid is discharged near the mist eliminator. And the absorbent can be recovered.

FIG. 3 is a first related invention of the present invention, and shows a schematic configuration of a wet gas processing apparatus of an absorption liquid gravity supply type which does not use an upward nozzle.

As shown in the figure, exhaust gas 1 from a combustion device such as a boiler is introduced from a flue gas introduction section 3 provided at a lower portion of an absorption tower 2, and flows through an exhaust gas flow path 2 A extending upward in the tower. A stream is formed and is discharged from the smoke discharge section 8 at the top of the absorption tower via the mist eliminator 6.

Further, a liquid reservoir 56 is provided at the lower part of the absorption tower 2 so that the absorbent 5 such as lime slurry dropped from the upper part of the tower 2 is stored and returned to the absorbent storage tank 27 via the recovery pump 21. is there.

On the other hand, at the exhaust gas passage 2A entrance just above the smoke exhaust introduction unit 3,
A large number of open-top gutter-shaped absorbing liquid pipes 31 are arranged substantially in parallel so as to traverse a plurality of the pipes in parallel so as to traverse in parallel. The liquid level of the storage tank 27 is set to be slightly higher than the liquid level of the trough-shaped absorption liquid pipe 31, and the absorption liquid 5 is passed through the absorption liquid introduction pipe 29 and the valve 60 by the action of gravity with an appropriate drop. After having been introduced into the header pipe 190 (see FIG. 5) in the tower, the absorption liquid 5 introduced into the gutter-shaped absorption liquid pipe 31 through the header pipe 190 becomes thinner from the upper surface of the side wall of the gutter-shaped absorption liquid pipe 31. In addition, it is configured so as to overflow toward the gap 30 sandwiched between the adjacent trough-shaped absorption liquid tubes 31. (See FIGS. 4 and 5.) The liquid surface 27a of the absorbing liquid storage tank 27 is connected to the trough-shaped absorbing liquid pipe 31.
Adjust the recovery amount from the recovery pump 21 and the recovery pipe 24a and the supply amount of the new absorption liquid 5 in accordance with the absorption liquid amount from the absorption liquid supply valve 60, so as to set it slightly higher than the liquid level. are doing.

FIG. 4 shows the arrangement of the trough-shaped absorbing liquid pipe 31. In FIG. 4 (A), the trough-shaped absorbing liquid pipe 31 is arranged along a horizontal plane substantially crossing the exhaust gas passage 2A inlet. The exhaust pipes 32 are arranged in parallel in a single row, and the gap 30 between the adjacent pipes of the pipe group is configured to allow the exhaust gas flow 32 to pass therethrough, and at the same time, absorption of lime slurry or the like that drips down the inner wall of the tower 2. In order to recover the liquid 5, 90 ° arc-shaped tubes 24 are provided on the inner wall of the tower on both the left and right sides.

According to such a configuration, a large number of gutter-shaped absorbing liquid pipes 31 are arranged at the inlet of the exhaust gas flow passage 2A via the predetermined gap 30. The passage area of the exhaust gas flow 32 is reduced, the speed is increased, and the speed is increased. And the void portion where the exhaust gas flow 32 has been accelerated
30 is caused to overflow 39 with the absorbing solution 5, and the high-speed rising exhaust gas flow 32
The absorption liquid 5 can be disturbed and atomized by the high velocity energy provided by the exhaust gas stream 32.

Further, the absorption liquid 5 recovered by the 90-degree arc tube 24 rises again by the gas, so that the power of the recovery pump 21 can be reduced.

FIG. 4 (B) shows the trough-shaped absorbing liquid pipe in a two-stage horizontal plane substantially transversely crossing the exhaust gas passage 2A inlet in a staggered manner.
31A and 31B are arranged side by side, and the adjacent tubes 31 of the arranged tube group
The exhaust gas flow 32 is configured such that the exhaust gas flow 32 is permeable to the gaps 30A and 30B between A and 31B, and in this case, the gutter-shaped absorption liquid pipe on the first stage side
The passage area of the exhaust gas flow 32 is reduced in the gap 30A between the 31A and the speed is increased to increase the speed. And the exhaust gas flow
4 (A) is the same as FIG. 4 (A) until the absorption liquid 5 flows out into the gap 30A whose speed has been increased and makes contact with the high-speed rising exhaust gas flow 32 in an intersecting manner. At the open position between the absorption liquid pipe 31A and the two-stage gutter-shaped absorption liquid pipe 31B, the high-speed fluid of the exhaust gas 1 forms a negative pressure due to the low speed and expansion of the accelerated gas flow 32, Fine particle atomization of the absorbing liquid 5 is also caused on the open surface of the first-stage gutter-shaped absorbing liquid pipe 31A, and the gap 3 between the second-stage gutter-shaped absorbing liquid pipes 31B again.
At 0B, the passage area of the exhaust gas flow 32 is reduced, the speed is increased and the speed is increased, and the same operation as described above is performed, thereby enabling more efficient gas-liquid contact. Of course, the number of stages may be three or more.

FIG. 5 discloses the flow state of the absorbing liquid 5 in the trough-shaped absorbing liquid pipe 31 of FIG. 4 (A).

In the figure, a header pipe 190 connected to the absorbing liquid introduction pipe 29 is disposed along, for example, a deep inner wall in the tower, and a side opening 190a of the header pipe 190 is orthogonal to the pipe axis. One end of a trough-shaped absorbing liquid pipe 31 arranged in parallel in the direction is connected to the opening.

As shown in FIG. 5 (A), the upper surface of both side walls of the trough-shaped absorbing liquid pipe 31 is set horizontally, and the absorbing liquid 5 extends over the entire length of the upper surface of the side wall of the trough-shaped absorbing liquid pipe 31. It is configured to overflow to the 30 side.

Since it is very difficult to set the upper surface of the side wall of the gutter-shaped absorbing liquid tube 31 horizontally, as shown in FIG. Multiple cutouts 31
a are provided at predetermined intervals, and the gap 30 is provided through the notch 31a.
The overflow 39 may be formed intermittently on the side so as to cross-contact with the high-speed exhaust gas flow 32.

According to this example of the apparatus, the exhaust gas 1 introduced into the absorption tower 2 with respect to the above-mentioned thin film overflow in the lateral direction passes through the gap 30 between the gutter-shaped absorption liquid pipes 31 arranged in a large number. As a result, a high-speed ascending air flow (exhaust gas tower speed is approximately 10 m / s) is formed and cross-contacts with the absorbing liquid 5 as described above. The droplets are dispersed into the upward airflow which is formed into fine droplets and expands in a turbulent manner at the upper part of the trough-shaped absorbing liquid pipe 31, and the upper surface of the trough-shaped absorbing liquid pipe 31 is also absorbed by the negative pressure from the open surface thereof. The liquid 5 is also atomized, dispersed and mixed, and makes efficient gas-liquid contact to form a gas-liquid dispersion gas.

The gas-liquid dispersion gas reaches the mist eliminator 6 above the absorption tower while forming a gas-liquid contact space 2A above the gas-liquid dispersion gas. During this time, the target components in the exhaust gas are absorbed from the exhaust gas 1 into the absorption liquid 5.

In the embodiment, the combination of the target component in the gas and the absorbing solution 5 is such that the target component soluble in the absorbing solution 5 is sulfur dioxide (S
O ₂ ), and the absorbing solution 5 uses a slurry containing limestone as an absorbing agent.

On the other hand, the exhaust gas 1 that has passed through the gas-liquid contact air space 2A is collected by the mist eliminator 6 to recover the dispersed absorbent 5, and is returned to the absorbent storage tank 27 via the recovery pipe 24a. The recovered absorbing liquid 5 is returned to the absorbing liquid storage tank 27 via the recovery pipe 24b from the recovering semi-circular arc tube 24 provided on the inner wall of the tower.

In the absorption tower 2, the target component is absorbed by the absorption liquid 5, and the accompanying absorption liquid 5 is separated by the mist eliminator 6. Sent to downstream equipment.

FIG. 6 shows another embodiment different from the trough-shaped absorbing liquid pipe shown above, wherein the absorbing liquid pipe 31 is constituted by a tubular member having an upper closed type, and the exhaust gas flow 32 of the absorbing liquid pipe 31 is formed. A slit-shaped opening or a large number of small hole rows is provided along the pipe axis direction on the peripheral surface facing the void portion 30 through which the air flows. In this case, as shown in the figure, in order to suppress the resistance of the fluid, the cross section of the lower surface side of the absorbent tube 31 is curved (for example, circular, streamlined,
For example, in FIG. 6 (A), the upper surface of a semicircular tubular member 31c having a circular cross section is formed on the upper surface of a semicircular tubular member 31c having a circular cross section. And a large number of small holes 36 or slit openings 37 (6th
(See FIGS. (D) and (E))).

The apparatus shown in FIG. 6 (B) uses a tubular member 34 having a hollow circular cross section, and has a large number of small holes 36 or slits along the axial direction on the left and right generating lines of the horizontal cross section including the axis. Opening
37 (see FIGS. 6 (D) and 6 (E)) is shown intermittently.

The embodiment shown in FIG. 6 (C) uses a tubular member 35 having an elliptical cross section, and a large number of small holes 36 or slit openings 37 along the axial direction on the left and right generating lines of the horizontal cross section including the axis.
(See FIGS. 6 (D) and 6 (E)). In addition, the small hole 36 or the slit opening 37
May not necessarily be provided on the left and right generatrix of the horizontal cross section including the axis, but may be provided above or below it.

Therefore, according to the present apparatus example, unlike the conventional upward nozzle, the absorbing liquid 5 may be allowed to overflow or outflow in a substantially horizontal direction toward the gap side between the adjacent pipes, so that equipment cost is reduced. And the effect of reducing energy can be obtained.

Further, in this device example, it is preferable that the absorption liquid supply to the absorption liquid tube is constituted by the absorption liquid supply source utilizing gravity, but the present invention may adopt a constitution using an absorption liquid supply pump. In this case, the feed pump may be small,
Also in this case, the effect of reducing equipment costs can be obtained.

Further, in the present device example, since a plurality of absorbent liquid pipes are arranged in a row at the inlet portion of the exhaust gas flow passage 2A via the predetermined gap portion 30, the exhaust gas flow
Efficient gas-liquid contact between the 32 and the absorbing liquid 5 and the supply of the absorbing liquid 5 can be performed simultaneously, and it is completed only when exhaust gas accompanies and blows through until the liquid column seen in the conventional liquid column type spreads out at the top. Large gas-liquid contact is performed more efficiently and in a shorter time than gas-liquid contact, which makes it possible to increase the efficiency of absorption / removal of the target component in the exhaust gas and to absorb the gas in a shorter time. Since the liquid 5 can be atomized and dispersed, the equipment cost can be reduced.

FIG. 7 is a schematic view showing a wet gas processing apparatus according to a second related invention of the present invention.

In FIG. 7, exhaust gas 1 from a combustion device such as a boiler is introduced into a flue gas introduction unit 3 installed at a lower part of an absorption tower 2. The introduced exhaust gas 1 comes into contact with the absorbing liquid 5 supplied from the absorbing liquid supply nozzle groups 4A to 4C installed in the lower part of the absorption tower 2, and the target component in the exhaust gas 1 moves from the gas 1 to the absorbing liquid 5. .

At this time, in the present embodiment, the combination of the target component in the exhaust gas 1 and the absorbing solution 5 is such that the target component soluble in the absorbing solution 5 is sulfur dioxide (SO ₂ ), and the absorbing solution 5 is limestone as the absorbing agent. A slurry was used.

In addition, a liquid reservoir 56 is formed at a lower portion in the absorption tower 2,
The liquid storage part 56 and each of the nozzles are stored by storing the absorption liquid 5 such as lime slurry and the like through a recovery pump 21, a buffer tank 22 for regeneration, a nozzle pump 23, and flow opening / closing valves 43A to 43C.
It communicates with the introduction pipe 49 of 4A-4C.

And the nozzle group is an upward nozzle group 4A-4C,
By injecting the absorbing liquid 5 upward from the upward nozzle groups 4A to 4C, the exhaust gas 1 introduced from the smoke exhaust introduction section 3 accompanies the absorbing liquid 5 ejected from the nozzle groups 4A to 4C. The gas-liquid contact is achieved by passing through the jet 5a of the absorbing liquid 5.

A mist eliminator 6 is disposed above the absorption tower 2 near the apex of the jet, and the mist eliminator 6 removes and collects the absorbent 5 accompanying the gas 1.

The purified gas 7 from which the target component is removed by the absorbing liquid 5 in the absorbing tower 2 and the absorbing liquid 5 entrained by the mist eliminator 6 is finally removed from the smoke exhausting section 8 to the atmosphere or after the necessary unillustrated Sent to the flow equipment.

On the other hand, a collecting device 9 having an upper side opened is disposed on the inner periphery of the side wall of the absorption tower 2 below the mist eliminator 6, and the absorbing liquid 5 captured by the mist eliminator 6 is collected by the collecting device 9, and the buffer tank 22. It is recycled if necessary through the use.

Therefore, it is preferable to set the flow rate of the exhaust gas 1 so that the height of the absorbing liquid 5 ejected from the upward nozzle groups 4A to 4C is pushed up by the flow rate of the exhaust gas 1 and rises to a position higher than the collecting device 9. In general, the load of a gas generation source such as a boiler fluctuates, and as described above, when the gas flow rate decreases, the absorption liquid 5 does not accompany due to a decrease in the gas flow rate.

Therefore, in the present embodiment, the upward nozzle group 4A
~ 4C in the three groups of left, center and right in the figure, each nozzle group 4A
Opening / closing valves 43A to 43C are provided on the absorption liquid introduction pipes 49 for every 4C to 4C so that the absorption liquid 5 can be ejected / stopped for each of the independent nozzle groups 4A to 4C. Note that the nozzle groups 4A to 4C are provided because a plurality of nozzles are arranged in a row in the front-rear direction although the number of nozzles appears as one in the drawing.

Divided plates 40A and 40B extending vertically extend between the left nozzle group 4A and the central nozzle group 4B and between the central nozzle group 4B and the right nozzle group 4C.

The upper ends of the split plates 40A and 40B are extended to the vicinity of the mist eliminator 6 mounting position higher than the collecting device 9, but the lower ends of the split plates 40A and 40B have different height positions. Is suspended down to the liquid level position of A in the liquid reservoir 56 of the absorbing liquid 5, and the other dividing plate 40
B is dripped down to a liquid level position of B higher than the liquid level of A to form three gas flow areas 41A, 41B, 41C partitioned by the dividing plates 40A, 40B.

According to this embodiment, the liquid level of the absorbing liquid 5 in the liquid reservoir 56 is raised by the pump drive control, and the liquid level is raised to the liquid level position of A. When the lower end of the split plate 40A is submerged in the absorbent 5, the gas introduction opening of the gas flow area 41A on the left is closed, and as a result, the flow area of the exhaust gas 1 introduced from the smoke exhaust introduction section 3 becomes the central area 41B. And only 41C on the right. By closing the open / close valve 43A of the left nozzle group 4A in this state, the gas flow passage area becomes 2/3 of only the center and the right exhaust gas flow regions 41B and 41C.

As a result, even if the introduction flow rate of the exhaust gas 1 is reduced to 2/3, the gas flow rate can be maintained at a constant value.
Can maintain the jetting height of the absorbing liquid 5 from the nozzle groups 4B and 4C along with the gas flow velocity, and the gas-liquid contact between the absorbing liquid 5 and the gas flow 32 can be performed smoothly.

Further, by raising the liquid level to the liquid level position of B, both lower ends of the two split plates 40A and 40B are immersed in the absorbing liquid 5, so that the left and central gas flow areas 41A and 41A The gas introduction opening of 41B is closed, and as a result, the basin of the exhaust gas 1 introduced from the smoke exhaust introduction section 3
C only. In this state, by closing the on-off valves 43A and 43B of the nozzle groups 4A and 4B on the left side and the central part, the gas flow passage area becomes 1 / of that of the right exhaust gas flow area 41C alone.
As a result, the introduction flow rate of the exhaust gas 1 is reduced to 1/3, and the gas flow rate can be kept constant.

Therefore, according to the present embodiment, when the gas flow rate in the absorption tower 2 decreases and the flow rate flowing through the exhaust gas flow path decreases in proportion thereto, the plurality of gas flow areas 41A to 41A By closing one side of 41C, the gas passage area can be controlled so as to keep the gas flow velocity constant in response to the decrease in the flow rate.

FIG. 8 shows a modification of the related invention shown in FIG.
The lower ends of A and 40B are bent 45 in a “J” shape toward the flue gas introduction section 3 introduced into the absorption tower 2.

According to such an example of the apparatus, the exhaust gas 1 introduced in a downward inclined direction from the smoke exhaust introduction section 3 into the absorption tower 2 is vertically upward along the “J” -shaped curved section 45 and the nozzle groups 4A to 4A to 4N.
The flow is guided while being rectified in the direction of the 4C jet, and as a result, the split plates 40A and 40B also function as exhaust gas rectifying plates, and gas-liquid contact can be performed more smoothly.

FIG. 9 shows another example of the apparatus according to the present invention, wherein the upward nozzle groups 4A and 4B are configured as two groups, left and right in the figure, and each nozzle group 4A,
Opening / closing valves 43A and 43B are provided on the inlet pipe 49 for each 4B so that the absorbing liquid 5 can be jetted / stopped for each of the independent nozzle groups 4A and 4B.

A vertically extending one dividing plate 40A is provided between the left nozzle group 4A and the right nozzle group 4B.

The dividing plate 40A is provided with a fulcrum 48 below the nozzle group 4A, 4B mounting position, and a pivoting plate 46 that pivots around the fulcrum 48 toward the smoke introduction section 3 is attached.

According to this embodiment, the rotating plate 46 is connected to the smoke introduction section 3.
By turning to a position slightly downward from the horizontal position toward the side and holding the position, the gas introduction openings of both the left and right gas flow areas 41A and 41B are opened, and normal gas-liquid contact is possible. Become.

Next, the rotating plate 46 is rotated vertically downward from the smoke exhaust introducing portion 3 toward the liquid reservoir 56, and the lower end of the rotating plate 46 is immersed in the absorbing liquid 5, so that the left gas flow area The gas introduction opening of 41A is closed, and as a result, the exhaust gas flow area introduced from the smoke exhaust introduction section 3 is only the right side 41B. In this state, by closing the open / close valve 43A of the left nozzle group 4A, the gas flow passage area becomes a half area of only the right side.

FIG. 10 is another modified example of FIG. 7. In order to explain the difference from the modified example of FIG. 9, the dividing plate 40A is vertically movable below the nozzle group 4A, 4B mounting position. An elevating plate 47 is provided. According to this embodiment, by raising the elevating plate 47 above the liquid reservoir 56, the gas introduction openings of both the left and right gas flow areas 41A and 41B are opened,
Normal gas-liquid contact is possible.

Next, the elevating plate 47 is moved vertically downward, and the elevating plate 47 is moved downward.
The lower end is submerged in the absorbing liquid 5, so that the gas introduction opening of the left gas flow area 41A is closed, and as a result, only the right exhaust gas flow area 41B is introduced from the smoke exhaust introduction section 3. In this state, by closing the open / close valve 43A of the left nozzle group 4A, the gas flow passage area becomes a half area of only the right side.

The split plate 40A may be configured to be movable in a horizontal direction orthogonal to the exhaust gas flow direction.

FIG. 11 is another modified example in which the dividing plate 40A is made movable, and the dividing plate 40A is moved in a direction substantially orthogonal to the exhaust gas flow direction.
It is configured to be movable from the left side wall of the absorption tower 2 to the center position,
By moving to the center position, the left nozzle group 4A and the right nozzle group
One divided plate 40A extending in the vertical direction is vertically provided between the divided plate 40A and the divided plate 40A.

The lower end of the dividing plate 40A is immersed in the absorbing liquid 5 in the liquid reservoir 56.

As a result, only the right exhaust gas flow area 41B of the dividing plate 40A is open to the gas introduction opening, and the exhaust gas 1 is introduced into the right exhaust gas flow area 41B as the dividing plate 40A is moved from the left side wall of the absorption tower 2 to the central position. The flow path cross-sectional area of the right gas flow area 41B can be reduced.

According to such an apparatus example, by moving the split plate 40A to the center side in accordance with the decrease in the exhaust gas flow rate, the gas flow areas 41A, 4A
The cross-sectional area of 1B can be freely reduced.

Therefore, according to this example of the apparatus, even when the gas flow rate in the absorption tower decreases due to load fluctuation of a combustion apparatus such as a boiler and the flow rate flowing through the exhaust gas flow path decreases in proportion thereto, the gas flow rate does not change. By controlling the gas passage area of the gas inflow area so that the pressure becomes constant, the ejection height of the absorbing liquid from the nozzle group can be maintained almost constant,
As a result, not only the gas-liquid contact between the absorbing liquid and the gas flow can be made smoothly, but also the absorbing liquid can be collected smoothly at the upper part of the absorption tower.

Further, according to the present example, unnecessary pump driving power and the like can be saved, and unnecessary circulation of the absorbent can be prevented.

Further, by closing one of the plurality of gas flow areas partitioned by the dividing plate or narrowing the gas passage area, the gas passage area is adjusted so that the gas flow velocity becomes constant in response to the decrease in the flow rate. Can be controlled.

Furthermore, by adjusting the liquid level of the absorbing liquid or by selectively lowering the lower end of the dividing plate to submerge in the absorbing liquid, the flow path of the gas flow area can be selectively opened and closed easily. .

Further, according to this example of the apparatus, the flow control or the opening and closing control of the gas inflow into the gas flow area can be easily performed by the swing deflection of the lower end side of the split plate.

Further, according to the apparatus shown in FIG. 8, the dividing plate also functions as an exhaust gas rectifying plate, and more smooth gas-liquid contact is possible.

Further, according to the apparatus shown in FIGS. 9 to 11, the sectional area of the gas flow area can be freely adjusted by moving the dividing plate in accordance with the fluctuation of the exhaust gas flow rate.

FIG. 12 shows a schematic configuration of a wet exhaust gas treatment apparatus according to a third related invention of the present invention, and a description of overlapping parts of the apparatus configuration described in the related invention will be omitted.

As shown in FIG. 12, the existing maintenance blow pit is located below the liquid reservoir 56, which is the absorption tower tank at the bottom of the absorption tower 2.
60 and a blow pit pump 60a are provided.

An electromagnetic opening / closing valve 67 is provided in a path 68 from the liquid reservoir 56 to the blow pit 60, and controls an exhaust gas flow rate (tower speed) from an exhaust gas flow rate detection sensor 65 provided in the smoke exhaust introduction section 3. Detected by the circuit 66, when the absorption tower 2 starts up and shuts down, the electromagnetic on-off valve 67 is opened until the flow rate of the exhaust gas 1 reaches the loading flow rate, and the liquid reservoir 56 → the blow pit 60 → the blow pit pump 60a → Pressurized tank 11
A bypass return path is formed to return to the bottom.

The space above the liquid level of the pressurized tank 11 provided outside the absorption tower 2 can be pressurized to an arbitrary pressure controlled by the control circuit 69 via the pressurizing compressor 17a and the pressure regulator 16. It is configured in.

The control circuit 69 detects the pressure on the inlet side of the absorbing liquid supply pipe 14 by the pressure sensor 62, and controls the pressure regulator 16 so that the absorbing liquid supply pressure to the nozzle 4 becomes constant. To control the applied pressure.

Thereby, even if the stored liquid level of the tank 11 fluctuates up and down,
The pressure applied to the space 11a above the liquid surface is controlled by the pressure regulator 16 in accordance with the fluctuation of the gravity of the absorbing liquid 5, so that the absorbing liquid 5 can be controlled regardless of the level of the liquid in the tank 11. Can be supplied at a constant rate.

Further, a mist eliminator 6 provided above the absorption tower 2
The recovery pipe 61 of the absorbent 5 separated by the
It is designed to be inserted below the liquid level.

As a result, the pressurized tank 11 → absorbent supply pipe 14 → nozzle 4
→ An entrainment process in which the target component is absorbed by gas-liquid contact with the exhaust gas 1 → Separation by the mist eliminator 6 → Recovery pipe 61 → A circulation system for returning to the pressurized tank 11 (hereinafter referred to as a main circulation system) is configured.

In this example of the apparatus, when the exhaust gas flow rate is 8 m / s or more, the jet flow 5a of the absorbent 5 ejected from the nozzle 4 is lifted up to the mist eliminator 6 by the exhaust gas 1, so that the absorbent 5 Circulates through the system.

That is, the absorbing liquid ejected by the nozzle 4 through the absorbing liquid supply pipe 14 by the biasing pressure of the pressurizing tank 11 obtained by controlling the pressure of the space 11a above the liquid level of the pressurizing tank 11 by the pressure regulator 16. The jet 5a of 5 is lifted up to the upper part of the absorption tower 2 and comes into contact with the ascending exhaust gas while entraining the jet velocity at a predetermined value, absorbs the target component of the exhaust gas 1 in the contact process, and removes the mist eliminator. Reach 6. The arrived entrained absorbing liquid is separated by the mist eliminator 6 and returned to the pressurized tank 11 via the recovery pipe 61.

Next, when the absorption tower 2 starts up or shuts down, as shown in FIG. 13, since the exhaust gas flow rate is lower than the loading speed, the absorption liquid 5
Jet 5a is not lifted to the upper part of the absorption tower by the exhaust gas 1, and the entire amount of the ejected absorbent 5 is almost completely discharged to the lower reservoir 56.
(Shown by reference numeral 5b).

At the same time, the exhaust gas flow rate (tower speed) from the exhaust gas flow rate detection sensor 65 provided in the smoke exhaust section 3 is detected by the control circuit 66, and the electromagnetic switching valve 67 is opened until the exhaust gas flow rate reaches the loading flow rate. And the reservoir 56 → blow pit 60
→ Blow pit pump 60a → Absorptive liquid 5 stored in the liquid reservoir 56 is returned to the tank 11 by the bypass return path of the pressurized tank 11.

That is, the absorbent 5b that has fallen into the liquid reservoir 56 is introduced into the existing blow pit 60 below, and can be stored in the blow pit 60 without special scale-up of the liquid reservoir 56. The air can be successively refluxed to the pressurized tank 11 by the blow pit pump 60a.

Even if the level of the stored liquid in the tank 11 fluctuates up and down due to the bypass circulation, the control circuit 69 detects the pressure on the inlet side of the absorbing liquid supply pipe 14 by the pressure sensor 62, and the supply pressure of the absorbing liquid to the nozzle 4 is reduced. By controlling the pressure in a constant direction by the pressure regulator 16, a constant supply of the absorbing liquid 5 can be made irrespective of the level of the liquid in the tank 11.

Therefore, this example of the apparatus has a space 11a above the liquid surface of the pressurized tank 11.
Can be pressurized under a predetermined pressure by the compressor 17a, so that there is no need to provide a circulation pump for ejecting the absorbing liquid 5 from the nozzle 4. However, the tip of the recovery pipe 61 needs to be inserted below the liquid level of the pressurized tank 11 to prevent air leakage.

Therefore, according to the present apparatus example, even when the exhaust gas speed is reduced due to the load fluctuation on the combustor side, the liquid storage tank at the bottom of the absorption tower and the second
The absorbent circulation path connected to the pressurized tank via the liquid storage tank is preferably used, and preferably the maintenance circulation system is effectively used to continuously circulate the absorption liquid. Can use existing blow pits and blow pit pumps, so it does not require special scale-up or increase in driving force for related equipment, and can be handled with low cost and low equipment burden.

Further, according to the present apparatus example, since the control of the jet pressure of the absorbing liquid can be arbitrarily controlled by the biasing pressure obtained by pressurizing the pressurizing tank, not only the jetting pump is not necessary, but also the pressurizing tank A constant supply of the absorbing liquid can be made irrespective of the level of the liquid.

When the absorption tower 2 is started up or shut down, as shown in FIG. 13, the exhaust gas flow rate becomes lower than the loading speed.
Jet 5a is not lifted to the upper part of the absorption tower by the exhaust gas 1, and the entire amount of the ejected absorbent 5 is almost completely discharged to the lower reservoir 56.
(Shown by reference numeral 5b). In order to solve such a drawback, conventionally, at the time of rising and shutting down the absorption tower, the exhaust gas discharged from a combustor, a boiler, or the like is passed through the absorption tower without passing the exhaust tower to the chimney side without passing through the absorption tower. After discharging, the exhaust gas is passed through the absorption tower for the first time after the exhaust gas flow rate has become equal to or higher than the loading flow rate at which the absorption liquid is lifted above the reference level, and there is an exhaust gas bypass system for that purpose.

Then, as shown in FIG. 17, the exhaust gas bypass system supplies exhaust gas 1 from a boiler or the like to a main path 74 connecting an exhaust gas discharge source such as a boiler or a combustor to an atmospheric emission portion of an exhaust gas such as a chimney. A bypass passage 72 having a damper 73 connected to the chimney and connecting the inlet side of the booster fan 71 and the outlet side of the absorber 2 while interposing the booster fan 71 for increasing the pressure to increase the speed and the wet absorption tower 2 described above is connected. When the absorption tower 2 rises and shuts down, the booster fan
With the stop of 71, damper 73 is opened and dampers 77, 78
And exhaust gas 1 discharged from a combustor, a boiler, or the like is discharged to the chimney side through a bypass path 72 bypassing the absorption tower 2 without passing through the absorption tower 2, and the flow rate of the exhaust gas is based on the absorption liquid 5. When the loading flow rate exceeds the level, the booster fan 71 is driven, the damper 73 is closed, the dampers 77 and 78 are opened and the bypass path 72 is closed. As shown, the gas passes through the main path 74, passes through the booster fan 71, undergoes necessary desulfurization treatment in the absorption tower 2, and discharges to the chimney side.

However, in such a conventional technique, since exhaust gas does not pass through the absorption tower at the time of startup and shutdown of the absorption tower, there is a problem that exhaust gas treatment is not performed and removal of sulfurous acid gas and dust contained in the exhaust gas becomes impossible. . In addition, if light oil that emits less SO ₂ and dust is burned to avoid this, there is a problem that the fuel cost increases.

FIG. 14 relates to a fourth related invention in which the same effect as the third related invention is obtained by effectively utilizing the conventional bypass path 72. The target component in the exhaust gas is converted to the absorbent 5 by gas-liquid contact between the main source 74 connecting the discharge source and the exhaust gas discharge part such as a chimney, etc., while entraining the absorbent 5 using the flow rate of the exhaust gas. 1 shows an exhaust gas treatment system in which a wet absorption tower 2 for absorption is interposed, (A) shows the open / close state of each damper and the flow of exhaust gas before the absorption tower is started, and (B) shows exhaust gas introduced from a boiler into the absorption tower. FIG. 4 is a diagram showing the opening / closing state of the damper and the flow of exhaust gas when the flow velocity in the tower is equal to or higher than the loading flow velocity.

As shown in FIG. 14, a main route 74 connecting an exhaust gas discharge source such as a boiler or a combustor to an atmospheric emission portion of an exhaust gas such as a chimney.
In addition, a booster fan 71 for increasing the speed of the exhaust gas 1 from the boiler or the like and a wet absorption tower 2 described above are interposed, and the inlet side of the pressure increase fan 71 and the outlet side of the absorption tower 2 are connected to each other to be connected to a chimney and to be connected to a damper. A bypass path 72 provided with 73 is provided.

In this example of the apparatus, at the time of startup before exhaust gas introduction into the absorption tower 2, the damper 73 is opened as shown in FIG. 14 (A) to form a pressurized circulation path by the bypass path 72 and the main path 74. , Without increasing the exhaust gas 1 from the boiler to the discharge path 76, and increasing the flow velocity of the gas in the circulation path.
This is continued until the flow velocity in the absorption tower 2 becomes equal to or higher than the loading flow velocity while increasing the speed by 71.

Then, when the flow rate in the tower is maintained at the loading flow rate or higher, the damper 73 of the bypass path 72 is closed to perform the exhaust gas 1 absorption treatment as shown in FIG. 14 (B).

The state of use of the pressurized circulation circuit will be described below with reference to a change diagram of the discharge exhaust gas amount with respect to the operation time of the boiler shown in FIG.

That is, as shown in FIG.
T ₁ and the operation before the end of the shutdown T ₂ are decreased quantity of exhaust gas, the column, among others the flow rate for the column in the flow rate of the absorption tower 2 for treating an exhaust gas 1 which is in the liquid falling velocity (loading velocity) V ₁ or less The opening and closing of the damper 73 is controlled as shown in FIG. 14 (A) until the flow velocity becomes equal to or higher than the loading flow velocity. When the flow velocity in the tower becomes higher than the loading flow velocity, the opening and closing of the damper 73 is performed as shown in FIG. 14 (B). The control is performed so that the operation of the absorption tower 2 is fully functioned.

FIG. 15 shows a second embodiment in which a dividing plate for regulating the width of the exhaust gas passage is provided in the absorption tower 2, and a dividing plate 40 extending in the vertical direction in the gas-liquid contact space 41 is provided. The gas-liquid contact airspace 41
Is configured to be movable in the horizontal direction so as to be able to change the exhaust gas passage area in the horizontal direction.

FIG. 16 is a third embodiment corresponding to FIG. 7 in which a dividing plate for regulating the width of the exhaust gas flow path is provided in the absorption tower 2, and the gas-liquid contact air space is provided.
A plurality of divided plates 40 having different height positions at the lower end in the vertical direction are provided in a stepwise manner on the 41, and the exhaust gas passage area is configured to be variable by controlling the lower liquid level.

When the flow velocity of the exhaust gas 1 introduced into the absorption tower 2 in the tower is equal to or less than the loading flow velocity, the exhaust gas passage area in the absorption tower 2 is reduced by the dividing plate 40, and the bypass path 72 is opened by the damper 73. Booster fan for treated exhaust gas
By returning to the inlet side of the absorption tower 2 via 71, the flow velocity of the exhaust gas 1 introduced into the absorption tower 2 in the tower can be rapidly increased.

Therefore, according to this example of the apparatus, the flow velocity in the tower can always be maintained at a value equal to or higher than the loading flow rate, so that the performance of the absorption tower can be completely maintained even when the plant is started up and shut down. There is no need to increase the capacity.

18 and 19 are a front view and a side view, respectively, showing an outline of a wet exhaust gas treatment apparatus according to a fifth related invention of the present invention. Arbitrary number of header pipes 190 each having a plurality of upward nozzles 4 are arranged in the middle of the absorption tower 2 in the height direction. Between the header pipe 190 and the liquid reservoir 56, an absorbing liquid supply pipe 14 with a circulation recovery pump 21 interposed therebetween is connected in communication, and with these, the absorbing liquid 5 is introduced into the absorption tower 2. Spraying to absorb and remove target components such as sulfur dioxide and dust is as described above.

A mist eliminator 6 is provided at a position above the absorption tower 2 and below the smoke discharge section 8.

Preferred examples of the mist eliminator 6 attached here include those clearly shown in FIG. The mist eliminator 6 is formed by arranging a plurality of plate members 6a having a cross section of a mountain shape (a flat V-shape) so as to overlap with a space therebetween and fixing them with a fixing bar 92. One plate material row 6a is located at the lower end position of another plate material row.
In order to converge to 6b, it is attached to the absorption tower 2 while being alternately inclined rightward and leftward. However, the shape and arrangement of the mist eliminator 6 are not limited to the example shown in FIG. 20, but as described later, in order to reduce the number of containers 80A that receive the absorbent 5 flowing down from the eliminator 6, a pair of adjacent mist eliminators 6 is used. The plate rows 6a, 6b may be alternately inclined so as to converge at their lower end positions, and the container 80A may be arranged in a direction crossing the plate rows 6a, 6b. In order to effectively capture the mist of the absorbing liquid 5 entrained by the mist eliminator 6, an interval at which the entrained flow can be ventilated is required.

Next, the main configuration of the present invention will be described. Below the mist eliminator 6, an arbitrary number of containers 80A such as a collecting gutter (see FIG. 20) capable of receiving the absorbing liquid 5 flowing down from the mist eliminator 6 are provided.
In this example of the apparatus, the number of the containers 80A is three, but it can be appropriately determined according to the arrangement state of the mist eliminators 6, the number of the mist eliminators 6, and the like.

Each container 80A is connected to the upper end of the return liquid pipe 81A, and the return liquid pipe 81A has a vertical pipe section 90 extended a required length downward, and the vertical pipe section The return absorption liquid 5c is given a potential energy (gravity energy) by 90 and extends to a position below the scattered absorption liquid reservoir zone in FIG. 5, and a nozzle-like opening 82A is provided at the lower end thereof.

Note that the length of the vertical pipe section 90 of the return liquid pipe 81A varies depending on the height of the ejected liquid column on the upward nozzle 4,
For example, it is preferable that the height is set to be equal to or higher than the height of the mist eliminator 6.

Specific configurations of the container 80A and the return liquid pipe 81A
This will be described in detail with reference to FIG. The container 80A provided at the lower end convergence position of the pair of plate material rows 6a and 6b extends horizontally in the tower 2 across the many eliminator lower end convergence positions, and slightly lowers the bottom surface of the container 80A. It is set so as to be inclined downward so that the return liquid 5c flows in one direction.

The upper end of the return liquid pipe 81A is connected to the side wall of the absorption tower 2 at the inclined downstream end of the container 80A, and communicates with the inclined downstream end of the container 80A.

Then, the return liquid pipe 81A has a U-shape, and the vertical pipe section 90 hangs down along the outer wall of the tower to the same extent as the height of the mist eliminator 6, and then penetrates horizontally again into the tower. A plurality of nozzle-shaped openings 82A at a predetermined distance in the axial direction on the lower surface side of the horizontal pipe portion 91 which is horizontally penetrated into the tower.
More specifically, at a position above the upward nozzle 4,
A nozzle-like opening 82A is provided at a position substantially immediately above the liquid column and below the scatter elimination liquid reservoir zone just below the mist eliminator 6, and the liquid 5c is returned from the nozzle-like opening 82A.
However, by utilizing the potential energy flowing down the vertical pipe section 90 (by the action of gravity), it sprays and collides with the ejected liquid column to form fine droplets, thereby enabling more efficient gas-liquid contact.

In the present example, the mist eliminator 6 is located above the top of the liquid column of the absorbing liquid 5 injected from the upward nozzle 4 and immediately below the mist eliminator 6 where the scattered absorbing liquid pool zone is likely to be generated (inlet).
, The downward length of the pipe 81A is set so as to be located below it.

A part of the return liquid pipe 81A may pass outside the absorption tower 2 as shown in FIG.
The entire structure including 90 may be provided so as to pass through the inside of the absorption tower 2.

Next, another embodiment of the present invention shown in FIG. 21 will be described.

In this example, only the configuration different from the embodiment shown in FIG. 19 will be described. In FIG. 21, members or portions indicated by the same reference numerals as those in FIGS. 18 to 20 represent members or portions having the same effect, and thus their description is omitted here without duplication.

In the second embodiment, the containers 80B are provided at the lower end convergence positions of the pair of mist eliminators 6, respectively, as in FIG.
After the collecting, the collecting pipe 80 is communicated with the upper end of the return liquid pipe 81B that hangs downward.

The return liquid pipe 81B hangs downward in the tower 2 and its lower end opening 82B is set so as to be located in the liquid reservoir 56, and the opening 82B is not formed in a nozzle shape unlike the above-described embodiment. It is just an opening.

Therefore, in the present apparatus example, unlike the apparatus according to the embodiment of FIGS. 18 and 19, the return liquid collected in the container 80B is not sprayed to a position above the liquid column-shaped jet flow, but is stored in the liquid storage section.
It is configured to return to 56.

Next, the operation of each of the device examples shown in FIGS. 18 to 21 will be summarized as follows.

When the flow rate of the exhaust gas 1 passing upward through the absorption tower 2 is increased to 5.5 m / s or more in the apparatus of each embodiment, the exhaust gas 1
Is attached to the mist eliminator 6, and a large amount of the absorbing liquid 5 flows downward. The absorbent 5 does not fall directly into the tower from the mist eliminator 6 but is collected by the containers 80A and 80B as it is, and the return liquid 5c collected by the containers 80A and 80B is returned by the return liquid piping 81A by gravity. , 81B, and in the apparatus example of FIGS. 18 and 19, the nozzle-like opening 82A is not located immediately below the mist eliminator 6 but at a position lower by the vertical length of the return liquid pipe 81A. Absorption tower 2 using gravitational energy
The return liquid 5c, which is jetted onto the jetting liquid column (absorbing liquid) of the upward nozzle 4 inside and is jetted from the nozzle-shaped opening 82A, collides with the jetting liquid column to form fine droplets, thereby achieving more efficient gas-liquid contact. It is configured to be possible.

On the other hand, in FIG. 21, the return liquid 5c collected in the container 80B is shown.
Is returned to the liquid reservoir 56, and is ejected upward again via the header pipe 190 and the ejection nozzle 4.

Therefore, in any of the above-described apparatus examples, the amount of droplets is not increased near the mist eliminator 6 which tends to form the scattered absorbing liquid pool zone, and the re-scattering of the absorbing liquid 5 due to the entrainment of the exhaust gas 1 in that portion is prevented. Is done.

FIG. 22 is a logarithmic graph showing the relationship between the gas flow rate in the tower and the mist concentration at the outlet of the mist eliminator, which was confirmed by the test, with the absorption liquid being extracted (the device of the present invention) and without the absorption liquid (the conventional device). ).

For example, in the conventional device ○ with a liquid column height of 1.7 m, when the gas flow rate in the tower exceeds 5.5 m, the mist outlet concentration sharply increases,
In the case of the invention device ● having a liquid column height of 1.8 m, the mist outlet concentration did not increase even if it exceeded 5.8 m.

Also, for example, in the conventional apparatus △ having a liquid column height of 3.4 m and the inventive apparatus ▲ having a liquid column height of 3.3 m, the mist outlet concentration at 5.8 m of the apparatus of the present invention is higher than that of the conventional apparatus. Therefore, it can be understood that it is greatly reduced to about 1/50 or less.

Therefore, from this figure, it can be seen that the device of the present invention has a gas flow velocity of about 5.
It turned out to be extremely excellent in the region of 5 m / s or more.

In this test, the apparatus of the embodiment of FIG. 21 was used as the apparatus of the present invention. Other conditions are as follows.
(Note that the height of the liquid column in the figure is the height of the columnar jet of the absorbing liquid.) Mist eliminator used: A bent plate type is used by inclining at 45 degrees. Mist eliminator and upward nozzle Distance: 8 m FIG. 23 is a graph showing the relationship between the gas flow rate in the tower and the mist scattering rate at the mist eliminator inlet confirmed by the test. The mist scattering rate (mist mist) at the eliminator inlet of the apparatus of the present invention is shown in FIG. Weight / total weight of the jetting absorbent × 100), there is no significant change between the conventional device ○ with a liquid column height of 2.4m and the invention device ● with a liquid column height of 1.9m, and both have low rates. However, the conventional device with a liquid column height of 2.8 m and the inventive device with a liquid column height of 3.3 m have a low mist scattering rate of the present invention, whereas the conventional device has a large You can see that it is increasing. As a result, even when the liquid column height was increased to about 3.3 m, the mist scattering rate was found to be sufficiently low even in the high-speed region where the gas flow velocity was about 5.5 m / s.

The apparatus used in this test is also that of the embodiment shown in FIG. Other conditions are as follows. (Note that the height of the liquid column in the figure is the height of the columnar jet of the absorbing liquid.) Mist eliminator used: A bent plate type is used by inclining at 45 degrees. Mist eliminator and upward nozzle Therefore, according to the present apparatus example, even if the flow rate of the exhaust gas in the absorption tower is increased, the mist of the absorbent discharged from the absorption tower accompanying the exhaust gas after the cleaning treatment is increased even if the flow rate of the exhaust gas in the absorption tower is increased. Since the amount is extremely small, the operation efficiency of the exhaust gas treatment can be improved by increasing the speed of the exhaust gas passing through the tower, which is extremely advantageous.

In addition, according to the apparatus example shown in FIGS. 18 and 19, the absorbent returned from the return liquid pipe to the absorption part immediately above the jet flow is discharged again along with the jet of the absorbent injected from the upward nozzle. Therefore, in addition to the above-described effects, the exhaust gas treatment performance can be maintained at a high level.

Further, according to the apparatus example shown in FIG. 21, even when the amount of the absorbing liquid reaching the mist eliminator is greatly increased, the absorbing liquid can be smoothly returned to the liquid reservoir and reused.

──────────────────────────────────────────────────続 き Continued on the front page (31) Priority claim number 10/232060 (32) Priority date August 18, 1998 (August 18, 1998) (33) Priority claim country Japan (JP) (31) ) Priority claim number 10/232061 (32) Priority date August 18, 1998 (August 18, 1998) (33) Priority claim country Japan (JP) (31) Priority claim number 10/232620 ( 32) Priority date August 18, 1998 (August 18, 1998) (33) Priority claim country Japan (JP) (31) Priority claim number 10/264332 (32) Priority date September 1998 (September 18, 1998) (33) Priority claim country Japan (JP) (31) Priority claim number Japanese Patent Application No. 9-325202 (32) Priority date November 11, 1997 (November 1997) .11) (33) Priority claim country Japan (JP) (31) Priority claim number Japanese Patent Application No. 10-48655 (32) Priority Japan February 13, 2010 (Feb. 13, 1998) (33) Priority claiming country Japan (JP) (31) Priority claim number Japanese Patent Application No. 10-232060 (32) Priority date August 18, 1998 ( (1988.18.18) (33) Priority claiming country Japan (JP) (31) Priority claim number Japanese Patent Application No. 10-232061 (32) Priority date August 18, 1998 (1998.18.18) ( 33) Priority claim country Japan (JP) (31) Priority claim number Japanese Patent Application No. Hei 10-232062 (32) Priority date August 18, 1998 (August 18, 1998) (33) Priority claim country Japan (JP) (31) Priority claim number Japanese Patent Application No. 10-264332 (32) Priority date September 18, 1998 (September 18, 1998) (33) Country claiming priority Japan (JP) (72) Invention Person Hirotsugu Nagayasu 2-5-1 Marunouchi, Chiyoda-ku, Tokyo Mitsubishi Heavy Industries, Ltd. Headquarters (72) Inventor Susumu Okino 4-6-22, Kannonshinmachi, Nishi-ku, Hiroshima-shi, Hiroshima Hiroshima Research Institute, Mitsubishi Heavy Industries (72 Inventor Masakazu Onizuka 4-6-22 Kanonshinmachi, Nishi-ku, Hiroshima-shi, Hiroshima Mitsubishi Heavy Industries, Ltd. Hiroshima Research Institute (72) Inventor Koichiro Iwashita 2-5-1 Marunouchi, Chiyoda-ku, Tokyo Mitsubishi Heavy Industries, Ltd. Head Office (72) Inventor Satoshi Nakamura 2-5-1 Marunouchi, Chiyoda-ku, Tokyo Mitsubishi Heavy Industries, Ltd. In-house (72) Inventor Kenji Inoue 4-6-22 Kanonshinmachi, Nishi-ku, Hiroshima-shi, Hiroshima Mitsubishi Heavy Industries, Ltd. Hiroshima Research Laboratory (56) References Open to the public Showa 59-131227 (JP, U) Open to the public Showa 49-117353 (JP, U) JP-A 54-34420 (JP, U) JP-A 6-36614 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) B01D 53/34-53 / 85 B01D 53/14-53/18 B01B 1/00-3/18 B01B 7/00-9/08

Claims (3)

(57) [Claims] 1. An absorption liquid stored in an absorption liquid storage section is jetted upward from a nozzle section in an absorption tower, and the jet stream is brought into gas-liquid contact with exhaust gas flowing through the absorption tower to convert a target component in the exhaust gas. In the wet gas processing apparatus for absorbing and removing, the absorption liquid storage section is formed by a pressurized tank that generates a pressurized gas in a space above the storage liquid surface, while collecting the absorption liquid that has absorbed the target component. Is disposed at a predetermined position in the absorption tower higher than the level of the stored liquid in the pressurized tank, and the outlet end opening of a communication pipe for returning the absorbent to the pressurized tank side from the recovery section is connected to the pressurized tank. A wet gas treatment device, wherein the wet gas treatment device is located in a storage liquid in the inside. 2. An absorption liquid stored in the pressurized tank can be jetted upward from a nozzle portion in the absorption tower by using an urging pressure of a pressurized gas in the pressurized tank. The wet gas processing apparatus according to claim 1, wherein: 3. The wet gas processing apparatus according to claim 1, wherein one of the target components to be absorbed and removed by said absorbing liquid is sulfur dioxide (SO ₂ ). A wet gas processing apparatus, wherein the oxygen-containing gas is blown into a storage liquid at the bottom of the pressurized tank.