JP2999420B2 - Supply device for fluid from nozzle - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to, for example, a facility provided in a facility for desulfurizing flue gas containing sulfurous acid gas by a wet lime method, wherein air and humidified water are absorbed from a nozzle in an absorbing solution for absorbing sulfurous acid gas. It relates to a device for supplying water.

[0002]

2. Description of the Related Art FIG. 6 is a vertical sectional view showing a part of an absorption tower 2 provided in a conventional flue gas desulfurization facility, and FIG. 7 is a horizontal sectional view of the absorption tower 2. For example, flue gas discharged from a thermal power plant contains sulfur dioxide (SO ₂ ) and is desulfurized by a flue gas desulfurization facility to prevent air pollution. The flue gas desulfurization equipment includes an absorption tower 2 in which an absorption liquid 3 in the form of a slurry containing calcium carbonate is stored. 5 are formed. The absorbing liquid 3 is pumped up by, for example, a pump (not shown) and sprayed in the gas phase region 5. The flue gas is supplied into the absorption tower 2 in the gas phase region 5 where the absorbing solution has been sprayed, is brought into contact with the absorbing solution 3, and the sulfur dioxide gas in the flue gas is absorbed by the absorbing solution 3 as sulfuric acid or sulfurous acid. It reacts with the calcium carbonate in the absorbing solution and is converted into gypsum and collected. Sulfurous acid gas is converted into sulfurous acid and absorbed liquid 3
When it is absorbed into the solution, sulfuric acid must be oxidized to sulfuric acid in order to cause a neutralization reaction with calcium carbonate and precipitate as gypsum. Air is blown into the absorbing solution 3 by the gas blowing device 6.

The gas blowing device 6 has a header 10 provided in the liquid phase region 4. The header 10 penetrates the side wall 2 a of the absorption tower 2 and extends horizontally in the diameter direction of the absorption tower 2. Part 11, a plurality of sub-headers 12 horizontally provided on both sides at intervals in the axial direction of the main header 11, and a plurality of nozzles provided downward at intervals in the axial direction of each sub-header 12. 13 is provided. An air supply pipe 14 is connected to the main header 11 of the header 10, air is supplied from an air source (not shown), and the air is discharged from each nozzle 13.

The absorption liquid 3 containing gypsum enters the nozzles 13 and adheres to the inner surface of each nozzle 13 due to fluctuations in air pressure, or droplets of the absorption liquid 3 containing gypsum adhere to the nozzles 13. In some cases, every two to three days,
The washing water is supplied from a water supply pipe 15 connected to the nozzles 13, and the washing water is discharged from each nozzle 13, thereby washing off the absorbing liquid 3 attached to the inner surface of each nozzle 13. However, when the adsorbed liquid 3 has been dried by the supplied air, as shown in FIG.
In some cases, the gypsum 16 is firmly adhered to such a position, cannot be washed away, and the nozzle 13 may be blocked. When the nozzle 13 is closed, the nozzle 13
Air cannot be discharged, the efficiency of air dispersion is reduced, the oxidation efficiency is reduced, and the desulfurization efficiency is reduced. Nozzle 13 causing such a decrease in desulfurization efficiency
In order to prevent the absorption liquid 3 adhering to the inside from drying out,
Supply a small amount of humidification water to the header 10 from each nozzle 13
To prevent the adsorbed liquid from drying out.

Another prior art is disclosed in Japanese Patent Application Laid-Open No. 6-21 / 1994.
In the flue gas desulfurization apparatus disclosed in Japanese Patent No. 8227, in order to prevent drying of the absorbent adhering to each nozzle, steam is mixed with air, and water is further mixed. It is supplied and discharged from each nozzle.

[0006] Still another prior art is disclosed in Japanese Patent Application Laid-Open No. H5-25-2.
In the flue gas desulfurization facility disclosed in Japanese Patent No. 96436, a water supply pipe is provided separately from a header for blowing air in the liquid phase region of the absorption tower, and the header and the water supply pipe are connected by a plurality of connection pipes in the absorption tower. Then, water is supplied to the header to wash each nozzle.

[0007]

In the apparatus as shown in FIGS. 6 and 7, the humidifying water is supplied together with air from the air supply pipe to the main header section 11 of the header 10 from one axial end thereof. The water supplied to the main header portion 11 is pushed by the air toward the other end in the axial direction, and the humidified water flows to the sub header portion 12 connected to the one end in the axial direction of the main header portion 11. In the region S surrounded by the imaginary line in FIG. 7, the absorbent 3 that has adhered to a relatively large number of nozzles 13 is dried, and the gypsum is fixed. For example, in one month of operation, about 40% of all the nozzles 13 are blocked,
As a result, the supply amount of air is initially 5000 Nm ³ /
It decreases from 3500 Nm ³ / hour from the time. In particular, when the absorption tower 2 is enlarged, a large amount of air must be discharged from the header 10, and the water is further pressed toward the other end of the main header 11 in the axial direction.

Further, in the apparatus disclosed in Japanese Patent Application Laid-Open No. 6-218227, it is necessary to separately provide a steam generation source such as a boiler in order to generate steam to be mixed with air. As well as the costs. In addition, air in a state where water vapor is saturated,
Water vapor may condense and liquefy during the movement inside the header due to contact with the inner wall of the header, resulting in a non-saturated state. In such a tip portion, there is a possibility that the absorbent adhering to the inner surface of the nozzle dries and adheres.

Further, in the apparatus disclosed in Japanese Patent Application Laid-Open No. 5-296436, the air supply pipe and the water supply pipe are connected by a plurality of connection pipes, and each pipe is provided in the absorbing solution. It is necessary to airtightly connect the water supply pipe and the connection pipe with the air supply pipe, which requires time and effort, and must be provided in an absorbing solution containing sulfuric acid and sulfurous acid. In addition, the connecting pipe must also be formed of a highly acid-resistant material, which increases costs. Further, the water supplied from the water supply pipe is supplied to the header for cleaning the nozzle, so that a large amount of water is required, and the flow volume of water in the header increases, and conversely, the flow of air increases. The product becomes small, and the air blowing efficiency decreases.

Accordingly, an object of the present invention is a device for supplying a fluid from a nozzle which can be realized at a low production cost, requires less labor for production, and can efficiently disperse and discharge gas in a wide range. It is to provide.

[0011]

SUMMARY OF THE INVENTION The present invention provides a horizontal main header portion, a plurality of sub header portions provided horizontally at intervals in the axial direction of the main header portion, and a plurality of sub header portions provided in the axial direction of the sub header portion. A gas and a humidifying liquid are supplied to a header including a plurality of nozzles provided downward with a gap, and a fluid supply device from a nozzle that discharges the humidifying liquid together with the gas from each of the nozzles, wherein the gas is A supply pipe is provided to the main header section, and an insertion pipe extending in the axial direction is provided in the main header section.A discharge pipe is connected to the insertion pipe at a position facing each sub header section, and each sub header section has A weir is provided at one end near the main header portion, and each of the discharge pipes extends into each sub-header portion and protrudes from the weir to a position closer to the tip of each sub-header portion; A discharge port is opened at one end of each sub-header part, and each of the nozzles is provided with an upper end protruding below the weir and to the same height in each sub-header part, and the humidifying liquid is separated from the gas. To the insertion tube,
The humidifying liquid in the insertion pipe is supplied from each discharge pipe to each sub-header section, and is discharged downward from each nozzle together with gas from each nozzle. According to the present invention, the gas is supplied to the main header portion, supplied from the main header portion to each sub header portion, and further dispersed and discharged to each nozzle. An insertion tube extending in the axial direction is provided in the main header portion, and a discharge tube is connected to the insertion tube at a position facing each sub header portion. Each sub-header section is provided with a weir at one end near the main header section, and each discharge pipe extends into each sub-header section, protrudes from the weir to a position closer to the tip end of each sub-header section, and the discharge port is It is open at one end of each sub-header. The humidifying liquid is supplied to the insertion pipe separately from the gas, and the humidification liquid in the insertion pipe is supplied from one of the discharge pipes to one end of each of the sub-headers. In addition, each nozzle is provided with its upper end protruding below the weir and to the same height in each subheader portion. The humidifying liquid supplied to one end of each sub-header portion is prevented from flowing to the main header portion by the weir, and is also stored in each sub-header portion up to the upper end portion of each nozzle. Rises as a whole, and water overflows and is discharged from each nozzle almost simultaneously. Since the insertion tube is provided in this way and the humidifying liquid is supplied to the insertion tube separately from the gas, a problem arises in that the humidification liquid is pressed by the gas and supplied to some of the sub-headers unevenly. The humidifying liquid can be supplied to each sub-header portion in an appropriate amount without being supplied to each sub-header portion.
The humidifying liquid supplied to each sub-header portion is stored in the sub-header portion and can be discharged from each nozzle on average, so by supplying the humidifying liquid to one end of each sub-header portion, Nozzle can be made wet by the humidifying liquid. Further, since the humidifying liquid is guided by the insertion tube provided in the header, it is not necessary to airtightly connect the header and the insertion tube as in the related art, and the manufacturing labor is reduced. Further, since the insertion tube is not exposed to the outside of the header and only comes into contact with the gas for discharge, there is no need to consider high acid resistance, and the insertion tube can be formed of an inexpensive low grade material. Further, since steam is not used, a source of steam is not required, and for example, a desulfurization facility provided with the fluid supply device is not enlarged, and the desulfurization facility can be realized at low cost.

[0012]

[0013]

Further, the present invention is an apparatus provided in a facility for desulfurizing a flue gas containing a sulfurous acid gas, for supplying gas to an absorbing solution for absorbing a sulfurous acid gas. Discharges the gas and the humidifying liquid in the absorbing liquid. According to the present invention, in a facility for desulfurizing flue gas, a supply device of a fluid from a nozzle is provided to supply a gas into an absorbing solution for absorbing lactic acid gas. Discharges gas and humidifying liquid. The gas is, for example, air, and sulfur dioxide gas is dissolved in water,
It is blown to oxidize the absorbed sulfurous acid to sulfuric acid. Calcium carbonate is mixed in the absorbing solution, and sulfuric acid and calcium carbonate are reacted to precipitate as gypsum,
We are collecting. The humidifying liquid is water, and can be kept in a wet state so that, for example, even if droplets of the absorbing liquid adhere to the nozzle, the liquid does not dry and adhere.

Further, the present invention is characterized in that the supply amount of the humidifying liquid is not less than an amount at which a gas present in the header can be kept saturated with the humidifying liquid. According to the present invention, the humidifying liquid is supplied in an amount larger than that capable of maintaining the saturated state of the gas present in the header. Thus, even if the humidifying liquid is completely vaporized in the header, the gas is saturated in that state. Therefore, even if foreign matter enters and adheres to the nozzle, the foreign matter does not dry and adhere.

[0016]

FIG. 1 shows an absorption tower 3 of a flue gas desulfurization facility 29 provided with a gas blowing device 30 according to one embodiment of the present invention.
1 is a simplified vertical cross-sectional view, and FIG.
1 is a horizontal sectional view of FIG. Exhaust gas, for example, exhaust gas discharged from a thermal power plant, contains sulfur dioxide (SO ₂ ) and is desulfurized by a flue gas desulfurization facility 29 to prevent air pollution. The flue gas desulfurization equipment 29 has an inner diameter of about 1
A 3000 mm cylindrical absorption tower 31 is provided. The absorption tower 31 has an absorption liquid 3 for absorbing sulfurous acid gas.
2 is stored, and a liquid phase region 33 and a gas phase region 34 are stored in the absorption tower 31.
Are formed.

The absorbing solution 32 contains calcium carbonate (Ca) in water.
CO ₃ ) in the form of a slurry.
2 is pumped by a pump 40 and
Is sprayed from the nozzle 41. The exhaust gas is supplied into the absorption tower 31 in the gas phase region 34 where the absorbing liquid 32 is sprayed, comes into contact with the sprayed absorbing liquid 32, and becomes SO ₂ + H ₂ O + ／ O ₂ → H ₂ SO ₄ . 1) or SO ₂ + H ₂ O → H ₂ SO ₃ (2) As shown in (2), the sulfur dioxide gas in the exhaust gas is dissolved in water and dissolved in sulfuric acid (H ₂ SO ₄ ) or sulfur dioxide (H ₂ SO ₃ ). Is absorbed by the absorbing liquid 32. Here, 1 / 2O ₂ in the equation (1)
Is oxygen contained in the exhaust gas. As described above, calcium carbonate is mixed in the absorbing solution 32, and when sulfurous acid gas is absorbed as sulfuric acid as shown in the above formula (1), the sulfuric acid becomes H ₂ SO ₄ + CaCO ₃ + H ₂ O → CaSO ₄ .2H ₂ O + CO ₂ (3) As shown in (3), neutralization reaction with calcium carbonate occurs, and gypsum (C
aSO ₄ .2H ₂ O). When the sulfurous acid gas is absorbed as sulfurous acid as shown in the above formula (2), it is subjected to a neutralization reaction with calcium carbonate to precipitate as gypsum as shown in the above formula (3), so that H ₂ SO ₃ + 1 / 2O ₂ → H ₂ SO ₄ ... It is necessary to perform an oxidation treatment as shown in (4). Sulfuric acid reacts with calcium carbonate as shown in the following equation (5): H ₂ SO ₃ + CaCO ₃ → CaSO ₃ .1 / 2H ₂ O + 1 / 2H ₂ O + CO ₂ (5) to form calcium sulfite (CaSO ₃ .1 / 2H ₂ O ) Is generated,
To gypsum of calcium sulfite, need to be oxidized as shown in _{CaSO 3 · 1 / 2H 2 O} + 1 / 2O 2 + 3 / 2H 2 O → CaSO 4 · 2H 2 O ... (6). As a device for blowing air for the oxidation treatment, the flue gas desulfurization facility 29 is provided with a gas blowing device 30 which is a device for supplying a fluid from a nozzle.

The gas blowing device 30 includes a header 35 provided in the liquid phase region 33 at a depth of about 4000 mm from the liquid surface.
Having. Since the header 35 is provided in the absorbing solution 32 containing sulfuric acid or sulfurous acid, it is made of, for example, stainless steel or resin (FRP) having excellent acid resistance. The header 35 includes three main headers 36a, 36b, 36c extending in parallel with each other and horizontally, and each main header 3
6a to 36c, a plurality of sub-headers 37 extending horizontally at intervals in the axial direction (the left-right direction in FIG. 2);
A plurality of nozzles 3 provided downward from each sub-header section 37 at intervals in the axial direction (vertical direction in FIG. 2).
8 is provided.

The central main header portion 36b of the main header portions 36a to 36c is a side wall 31a of the absorption tower 31.
And extends in the diametrical direction of the absorption tower 31, for example, a 300A tube 90a at the base end and a 250A tube 9 at the tip end.
0b are connected to each other. The main header portions 36a and 36c on both sides of the central main header portion 36b are
The 200A tubes 91a and 92a at the base end and the 150A tubes 91b and 92 at the tip end penetrate the side wall 31a of the absorption tower.
b are connected to each other.

The center main header portion 36b is provided with a 40A sub-header portion 37 extending on both sides thereof, and the main header portions 36a and 36c on both sides except for the vicinity of the other end portion in the axial direction. A 40A sub-header portion 37 is provided extending to the opposite side of the main header portion 36a. Each sub-header 37 has a different length according to the shape of the absorption tower 31. Each sub-header section 37 is provided, for example, every 500 mm, and each sub-header section 37 is provided with a nozzle 38 having an inner diameter of 8 mm extending 300 mm downward every 500 mm. For example, taking the subheader section 37a shown in FIG. 2 as an example, the positions of the nozzles are indicated by crosses. The same applies to the other subheaders 37. As described above, the nozzles 38 are provided on the header 35 substantially uniformly in accordance with the shape of the absorption tower 31.

An air supply pipe 39 is connected to the base end of each of the main headers 36a to 36c, and air is supplied to the main headers 36a to 36c via the air supply pipe 39. The air supplied to each of the main headers 36 a to 36 c is distributed to each of the sub headers 37, and is discharged from each of the nozzles 38 into the absorbing liquid 32. Thereby, the air can be evenly dispersed and blown into the absorbing solution 32 in the absorbing tower 31, and the oxygen in the air can be efficiently contacted with the sulfurous acid in the absorbing solution 32 to cause an oxidation reaction.
Since the header 35 having each sub header portion 37 is used in this manner, even if the absorption tower 31 is large, the number of places where the header 35 penetrates the side wall 31a of the absorption tower 31 is reduced.
Strength reduction can be reduced.

A stirrer 44 is provided below the absorption tower 31 to stir the absorption liquid 32 to further promote the oxidation reaction. Further, by stirring using the stirrer 44, a neutralization reaction of sulfuric acid with calcium carbonate can be promoted.

FIG. 3 is a simplified axial cross-sectional view of the sub-header section 37 taken along the line III-III in FIG. Referring also to FIG. 1 and FIG.
a to 36c have insertion tubes 42 extending in the axial direction thereof.
a, 42b, and 42c are the main headers 36a to 36c, respectively.
c supported by support pieces 49 spaced apart in the axial direction of c,
Each is provided. Each of the insertion tubes 42a to 42c is
Since it does not come into contact with the absorbing liquid 32, there is no need to consider acid resistance, and it is made of a low-grade material, for example, steel, which is cheaper than stainless steel. Each insertion tube 42a-42c
Is connected to a discharge pipe 45 at a position facing each sub-header section 37, each discharge pipe 45 extends into each sub-header section 37, and its discharge port 45 a is connected to each main header section 36 a to 36 c of each sub-header section 37. It is open at the closer end 37b. The inner diameter of each discharge pipe 45 is selected according to the length of the sub-header section 37 or the number of nozzles 38 provided in the sub-header section 37 so that necessary humidifying water can be supplied. 5 mm is selected.

A water supply pipe 46 is connected to the base end of each of the insertion pipes 42a to 42c.
Humidifying water, which is a humidifying liquid, is supplied to 2 c via a water supply pipe 46. The humidified water supplied to each of the insertion pipes 42 a to 42 c is supplied from each discharge pipe 45 to one end 37 b of each sub header section 37. Thus, each of the insertion tubes 42a to 42
c, the humidifying water is separately supplied with the air, so that the humidifying water is pressed by the air having the flow velocity of 20 to 30 m / sec and is supplied to some of the sub-headers 37 unevenly. There is no need to set the mounting levels of all the nozzles 38 with very high accuracy, and water can be evenly supplied to each sub-header section 37. Further, there is no need to separately insert the insertion tubes 42a to 42c into the side wall 31a of the absorption tower 31, and there is no reduction in strength. Further, since it does not come into contact with the absorbing liquid 32, it is not necessary to frequently perform the removal work and the inspection work of the attached gypsum, and the maintenance property is excellent.

Further, one end 37b of each sub header section 37
Is provided with a weir 47, and each discharge pipe 45 protrudes from the weir 47 to a position closer to the distal end 37 c of the sub-header section 37. By providing such a weir 47, the water supplied to each sub header section 37 is
It does not flow to a to 36c. Further, as shown in FIG. 4, each of the nozzles 38 has an upper end portion 38a provided in each of the sub-headers 38 so as to protrude below the weir 47 and to the same height. As a result, the water is placed in the sub header section 37 at the upper end portions 38 of the nozzles 38.
a, and even if water is supplied to one end of the sub-header section 37, the water level in the sub-header section 37 rises as a whole, and the water overflows from each nozzle 38 almost simultaneously and is discharged. . With such a configuration, the humidifying water can be discharged from each nozzle 38 on average, and all the nozzles 38 can be in a wet state.

The absorbing solution 32 contains gypsum, calcium sulfite, and dust (ASH) in addition to the above-mentioned calcium carbonate.
15% by weight of a solid content such as
Droplets adhere to the nozzle 38 or the absorbing liquid 3
2 enters and adheres to the nozzle 38 due to a change in air pressure or the like, and then dries as described above.
Solids, especially gypsum, stick to the nozzle 38. However, since each nozzle 38 can be kept wet,
Even if the absorbing liquid 32 adheres, the adsorbing liquid 32 does not dry. Therefore, the adsorbed liquid 32
Even if contains gypsum, the gypsum does not dry and firmly adhere.

A water supply pipe 50 is connected to the air supply pipe 39. The water is supplied to the header 35 periodically, for example, about once every two or three days, and the inside of each nozzle 38 is cleaned. The nozzle 38 can be washed out even if gypsum adheres, so that the nozzle 38 is not blocked. Further, when the supply of air is stopped, it is possible to keep the header 35 in a state where the washing water is stretched,
It is possible to prevent the absorbing liquid from entering the nozzle 38 and drying. Therefore, nozzle 3
8 can be prevented from being closed.

FIG. 5 is a system diagram showing a control system of the flue gas desulfurization facility 29. The above-described oxidizing air is supplied to each of the main header portions 36 a to 36 c of the header 35 via the air supply pipe 39 by the blower 56. A check valve 57 is interposed in the middle of the air supply pipe 39, and the absorption liquid 32 is supplied to the header 3.
Backflow from 5 toward the air supply pipe 39 is prevented. The humidifying water is supplied from the humidifying water tank 58 to the pump 5.
9 and is supplied to each of the insertion pipes 42 a to 42 c via a water supply pipe 46. A flow control valve 62 is interposed in the middle of the water supply pipe 46 to control the flow rate of the humidifying water. Further, the above-mentioned washing water is pumped up from a washing water tank 60 by a pump 61, and is supplied from an air supply pipe 39 to each of the main header portions 36 a to 36 c of the header 35 via a water supply pipe 50. In the middle of the water supply pipe 50, a flow control valve 63 is interposed,
It is possible to control the flow rate of the washing water.

The flue gas desulfurization equipment 29 is provided with a control means 55 for controlling the air, humidification water and washing water for efficient desulfurization. The control unit 55 includes a gas amount of the exhaust gas supplied to the absorption tower 31 per unit time, sulfur of the exhaust gas, that is, a sulfurous acid gas (SO 2).
₂ ) Concentration and absorbent composition data are given.

For example, when the amount of exhaust gas supplied per unit time is 1200000 Nm ³ / hour, the supply amount of air is 5500 Nm ³ / hour, and the supply amount of humidifying water with respect to this supply amount of air is: 2.5 tons / hour. The air is supplied at about 90 ° C.,
° C, and the humidifying water in the header 35 is in a state of being easily evaporated, but the amount of the humidifying water is equal to or more than the amount that can keep the air existing in the header 35 saturated with the humidifying water. The absorption liquid 32 adhered to the inside 38 is prevented from drying. The supply amount of the air is controlled by controlling the blower 56 by the control unit 55 while comparing the detected value with the flow rate detector 64 provided in the middle of the air supply pipe 39. The supply amount of humidification water is
The control unit 55 controls the flow rate control valve 62 by operating and controlling the flow rate control valve 62 while comparing the value with a value detected by a flow rate detector 65 provided in the middle of the water supply pipe 46.

When the deviation between the set value of the air supply amount by the control means 55 and the value detected by the flow rate detector 64 is larger than a predetermined value, the nozzle 38 is caused by the absorbing liquid 32 attached to the nozzle 38. It is determined that the washing water is being closed, and the flow rate control valve 63 is operated and controlled to supply the washing water of several tens to ten.
Cleaning is performed by supplying at a flow rate of several 100 m ³ / hour for a few minutes. With this configuration, air can be uniformly discharged from each nozzle 38.

[0032]

[0033]

[0034]

[0035]

Further, as another embodiment of the present invention, a gas blowing device may be provided in a desulfurization facility using another method or a facility for another purpose. Further, the supplied gas may be a gas other than air, and the humidifying liquid may be a fluid other than water.

[0037]

As described above, according to the present invention, it is possible to supply a humidifying liquid to each sub-header part in an amount required as needed, and to store the humidifying liquid in each sub-header part. Thereby, the humidifying liquid is discharged from each nozzle in each sub-header part on average, and in the header having a structure in which the sub-header part branches from the main header part,
All the nozzles can be kept wet so that the liquid or the like adhering to each nozzle is not dried. Therefore, the foreign matter can be prevented from sticking to all the nozzles of the header, the foreign matter can be easily washed away, and a decrease in gas supply efficiency can be prevented. In this way, it is possible to reliably supply gas from each nozzle, so in order to prevent a drop in operating efficiency, consider using a large number of nozzles, taking into account that some of the nozzles will be blocked. There is no need to provide them, and only the required number of nozzles may be provided. Further, since the gas and the humidifying liquid are separately supplied to the sub-header section, even when the gas is supplied to a wide area, the necessary amount can be obtained and supplied to each sub-header section by the calculation formula. Therefore, the length of the sub-header portion and the number of nozzles can be arbitrarily determined according to the shape of the gas supply region, and the degree of freedom in design is high. In addition, the height of each sub-header portion is made uniform, and there is no need to set the mounting levels of all nozzles in the header with very high accuracy. Further, since the humidifying liquid is guided by the insertion tube provided in the header, it is not necessary to connect the header and the insertion tube airtight as in the related art,
Low production effort. Further, since the insertion tube is not exposed to the outside of the header, it is formed of an inexpensive low-grade material without contacting only with the gas for discharge, for example, there is no need to consider high acid resistance as in the related art. It is possible. Further, since no steam is used, a source of steam is not required, the desulfurization equipment is not increased in size, and the desulfurization equipment can be realized at low cost.

[0038]

[0039]

Further, according to the present invention, in a facility for desulfurizing flue gas by a wet lime method, a device for supplying a fluid from a nozzle for supplying a gas into an absorbing solution for absorbing a oxyflux gas is provided. The gas and the humidifying liquid are discharged from each nozzle in the absorbing liquid. The gas is, for example, air and is blown to dissolve the sulfurous acid gas in water and oxidize the absorbed sulfurous acid to sulfuric acid. Calcium carbonate is mixed in the absorbing solution, and sulfuric acid and calcium carbonate are reacted to precipitate and recover as gypsum.
The humidifying liquid is water, and can be kept in a wet state so that, for example, even if droplets of the absorbing liquid adhere to the nozzle, the liquid does not dry and adhere.

Further, according to the present invention, the humidifying liquid is supplied in an amount equal to or more than the amount capable of maintaining the saturated state of the gas present in the header. Thus, even if the humidifying liquid is completely vaporized in the header, the gas is saturated in that state. Therefore, even if foreign matter enters and adheres to the nozzle,
The foreign matter is not dried and fixed.

[Brief description of the drawings]

FIG. 1 is a simplified vertical sectional view showing an absorption tower 31 of a flue gas desulfurization facility provided with a gas blowing device 30 according to an embodiment of the present invention.

FIG. 2 is a horizontal sectional view of the absorption tower 31.

FIG. 3 is a simplified axial cross-sectional view of a sub-header section 37 as viewed from a cutting plane line III-III in FIG. 2;

FIG. 4 is a simplified sectional view perpendicular to the axis of the sub-header section 37.

FIG. 5 is a system diagram showing a control system of the flue gas desulfurization facility.

FIG. 6 is a vertical sectional view showing a part of an absorption tower 2 provided in a conventional flue gas desulfurization facility.

FIG. 7 is a horizontal sectional view of the absorption tower 2.

FIG. 8 is a cross-sectional view showing the nozzle 13 on which gypsum 16 is attached.

[Explanation of symbols]

 Reference Signs List 30 gas blowing device 31 absorption tower 32 absorption liquid 35, 70, 80 header 36a to 36c main header part 37 sub header part 38 nozzle 42a to 42c insertion pipe 47 weir 71 branch pipe 72 through hole

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-6-218227 (JP, A) JP-A-63-137741 (JP, A) JP-A-2-83026 (JP, U) (58) Field (Int.Cl. ⁷ , DB name) B01D 53/50 B01D 53/77 B01J 4/00

Claims (3)

(57) [Claims] 1. A horizontal main header, a plurality of sub-headers provided horizontally at intervals in the axial direction of the main header, and a plurality of downwards provided at intervals in the axial direction of the sub-header. A gas and a humidifying liquid are supplied to a header including the nozzles, and a fluid supply device from a nozzle that discharges the humidifying liquid together with the gas from each of the nozzles, wherein gas is supplied to the main header portion, An insertion tube extending in the axial direction is provided in the main header portion, and a discharge tube is connected to the insertion tube at a position facing each subheader portion. Each subheader portion has one end near the main header portion. The discharge pipe extends into each sub-header part, protrudes from the weir to a position closer to the tip of each sub-header part, and a discharge port is provided in each sub-header. The upper end of each of the nozzles is provided below each weir and protrudes to the same height in each of the subheaders, and the humidifying liquid is supplied to the insertion pipe separately from the gas. And a humidifying liquid in the insertion pipe is supplied from each discharge pipe to each sub-header section, and is discharged downward together with gas from each nozzle. 2. An apparatus provided in a facility for desulfurizing flue gas containing sulfurous acid gas to supply gas into an absorbing solution for absorbing sulphite gas, wherein each of the nozzles is provided with an absorbing solution. The apparatus for supplying a fluid from a nozzle according to claim 1, wherein the gas and the humidifying liquid are discharged therein. 3. The nozzle according to claim 1, wherein the supply amount of the humidifying liquid is equal to or larger than an amount at which a gas present in the header can be kept saturated with the humidifying liquid. Fluid supply device.