KR101269707B1 - Equipment for the desulfurization of flue gas with seawater and process for treatment of the seawater used in the desulfurization - Google Patents

Abstract

 In the first seawater treatment apparatus 10-1 according to the present embodiment, the flue gas desulfurization absorption tower 13 for purifying the sulfur component in the exhaust gas 11 by contacting the absorption seawater 12A which is a part of the seawater 12 and purifying it. And sulfur formed by being integrally installed below the flue gas desulfurization absorption tower 13 and contacting the sulfur component in the exhaust gas 11 with the absorbing sea water 12A in the flue gas desulfurization absorption tower 13 to desulfurize sea water. The lower end of the side wall 17 of the flue gas desulfurization absorption tower 13 while having the dilution mixing tank 16 which mixes and dilutes the component absorption seawater 14A with the dilution seawater 12B supplied to the main body 15. The lid part 18 extended along the longitudinal direction of the dilution mixing tank 16 so that the dilution mixing tank 16 may be covered by the side, and is dripped from the back surface side of this lid part 18, and the dilution mixing tank 16 is carried out. It has the gas retention part 20A provided with the 1st bank 19 which the edge part embeds in the surface of the water.

Description

EQUIPMENT FOR THE DESULFURIZATION OF FLUE GAS WITH SEAWATER AND PROCESS FOR TREATMENT OF THE SEAWATER USED IN THE DESULFURIZATION}

The present invention relates to a seawater flue gas desulfurization apparatus, a seawater flue gas desulfurization system, and a desulfurization sea water treatment method for desulfurizing sulfur components such as oxide sulfur in exhaust gas of an industrial combustion facility using sea water.

In recent years, thermal power plants with seawater flue gas desulfurization devices have tended to increase. Since power plants and the like require large amounts of cooling water, seawater is often used as an absorbent liquid in view of the fact that it is often constructed in a location facing the sea, and that the cost of equipment for desulfurization treatment can be kept lower than that of the lime-gypsum method. The desulfurization of seawater using desulfurization has been noted.

In thermal power plants, since a large amount of seawater is used as cooling water in a boiler condenser, a portion of the seawater drainage discharged from the condenser is heated to the seawater flue gas desulfurization system, and used as an absorbent for seawater flue gas desulfurization. The removal of SO _{2 in} the exhaust gas is performed.

An example of the flowchart of the thermal power generation system provided with the seawater flue gas desulfurization apparatus using the conventional seawater is shown in FIG. As shown in FIG. 9, the thermal power generation system 100 using the conventional seawater flue gas desulfurization apparatus uses the preheated air 101, and the boiler 102 and the boiler 102 which burn by the burner which is not shown in figure. The dust collecting device 104 which removes the dust in the exhaust gas 103 which heat-exchanges and discharges | evaporates, and the sulfur component which desulfurizes and desulfurizes the sulfur component in the exhaust gas 103 using the seawater 105 It consists of the seawater flue gas desulfurization apparatus 107A which performs the water quality recovery process of the sulfur component absorption seawater 106 containing a high concentration. This seawater flue gas desulfurization apparatus 107A includes a flue gas desulfurization absorption tower 108 which recovers SO ₂ in the exhaust gas 103 as sulfurous acid (H ₂ SO ₃ ), and sulfur discharged from the flue gas desulfurization absorption tower 108. It consists of the oxidation tank 109 which performs the water quality recovery process of the sulfur component absorption seawater 106 containing a high concentration of a component (patent document 1, 2).

The exhaust gas 103 generated by combustion in the boiler 102 is fed to a flue gas denitrification apparatus (not shown), denitrated, and then fed to the dust collector 104 and exhaust gas 103. ) Sold out. In addition, the exhaust gas 103 damped by the dust collector 104 is supplied into the flue gas desulfurization apparatus 108 of the seawater flue gas desulfurization apparatus 107A by the attraction fan 110.

In the flue gas desulfurization absorption tower 108, desulfurization is performed using absorbing seawater 105A, which is part of the seawater 105 which is pumped out of the sulfur component in the exhaust gas 103 from the sea 111. In other words, the exhaust gas 103 generated by burning the fossil fuel contains a sulfur component of sulfur oxide (SO _X ) in the form of SO ₂ or the like. In seawater desulfurization, gaseous contact of absorption seawater 105A supplied through the exhaust gas 103 and the seawater supply line 112 in the flue gas desulfurization absorption tower 108 allows absorption of SO ₂ in the exhaust gas 103. It is made to absorb in seawater 105A. In addition, the purge gas 113 desulfurized in the flue gas desulfurization absorption tower 108 is discharged from the chimney 115 to the atmosphere through the purge gas discharge passage 114. In the flue gas desulfurization absorption tower 108, the reaction as shown by the following equation occurs by the contact of the seawater 105A and the exhaust gas 103.

[Reaction Scheme I]

_{SO 2 (g) + H 2} O → H 2 SO 3 (l) → HSO 3 - + H +

The gas-liquid contact between the seawater 105A and the exhaust gas 103 absorbs SO ₂ in the exhaust gas 103 to generate H ₂ SO ₃ , which dissociates in the seawater 105A, and therefore, the seawater 105A and the exhaust gas. In the seawater 105A after the gas 103 is brought into gas-liquid contact, the concentration of HSO ₃ ⁻ increases and the pH is lowered because H ⁺ is released. The pH of the sulfur component absorbing seawater 106 generated by absorbing a large amount of sulfur component is about 3 to about 6.

The sulfur component absorbing seawater 106 discharged from the flue gas desulfurization absorption tower 108 should be raised to 6.0 or higher before being discharged or reused into the sea 111. Therefore, the sulfur component absorbing seawater 106 including the sulfur component mixes a part of the seawater 105 supplied by the secondary seawater supply line 116 in the oxidation tank 109 as the dilution seawater 105B. In addition, the air 118 is supplied from the oxidation air blower 117 into the oxidation tank 109 through the nozzle 120 of the diffuser 119, and the sulfur component absorbing seawater is brought into contact with the gas-liquid. The reaction is performed as shown in the following equation, and then, by diluting the remaining seawater 105 as the dilution seawater 105C by the tertiary seawater supply line 121, the sulfurous acid which becomes a COD source is reduced, and the dissolved oxygen concentration The water quality is restored by raising the pH, and the water quality is released into the sea 111 as the sea water 122.

[Reaction Scheme II]

O ₂ (g) → O ₂ (l)

[Reaction Scheme III]

^{_{HSO 3 - + 1/2 O 2 (}} l) → + SO 4 2- + H +

[Reaction Scheme IV]

_{^{HCO 3 - + H + → H}} 2 CO 3 (l) → CO 2 (g) ↑ + H 2 O

[Reaction Scheme V]

CO ₃ ^2- + 2 H ⁺ → H ₂ CO ₃ (l) → CO ₂ (g) ↑ + H ₂ O

As described above, in the thermal power generation system 100 using the conventional seawater flue gas desulfurization apparatus, in order to prevent the dissipation of SO _{2 in} the oxidation tank 109 and improve the pH, a condenser not shown in the sulfur component absorbing seawater 106 is shown. By diluting the seawater 105 discharged from the mixture with the oxidizing tank 109 and oxidizing and aeration in the oxidizing tank 109, the sulfurous acid is oxidized and detoxified, and the dissolved oxygen concentration is increased and decarbonized. The pH of the sulfur component absorbing seawater 106 is improved, and the pH of the seawater drainage 122 is discharged so as to satisfy the drainage standard (normally pH 6.0 or higher) (Patent Documents 1 and 2).

Moreover, the other structure of the conventional seawater flue gas desulfurization apparatus is shown in FIG. 10 is a diagram briefly showing another configuration of the seawater flue gas desulfurization apparatus applied to the conventional seawater desulfurization system. As shown in FIG. 10, another conventional seawater flue gas desulfurization apparatus 107B includes a flue gas desulfurization absorption tower 131 for desulfurizing and reacting SO ₂ in the exhaust gas 103 with sulfurous acid (H ₂ SO ₃ ), and flue gas desulfurization. The dilution mixing tank 132 which is provided below the absorption tower 131, and dilutes and mixes the sulfur component absorption seawater 106A containing a sulfur component with the dilution seawater 105B, and the downstream side of the dilution mixing tank 132. It is provided in the and consists of the oxidation tank 133 which performs the water quality recovery process of the sulfur component absorption seawater 106 (patent document 3).

In the seawater flue gas desulfurization apparatus 107B, gaseous liquid 105A of absorption seawater 105 which is a part of the seawater 105 supplied through the seawater supply line 112 in the flue gas desulfurization absorption tower 131 is brought into gas-liquid contact with the exhaust gas 103. The SO ₂ in the exhaust gas 103 is absorbed into the absorbing seawater 105A. The sulfur component absorbing seawater 106A absorbing the sulfur component from the flue gas desulfurization absorption tower 131 is the dilution seawater supplied to the dilution mixing tank 132 provided at the lower portion of the flue gas desulfurization absorption tower 131. 105B). The dilute seawater 105B and the sulfur component absorbing seawater 106B mixed and diluted are fed to an oxidizing tank 133 provided on the downstream side of the dilution mixing tank 132 to oxidize the air blower 117. Air 118 is supplied through the nozzle 120 for the oxidizing air of the diffuser 119 to recover the water quality, and then discharged.

Japanese Patent Publication No. 2006-055779 Japanese Patent Publication No. 2007-125474 International Publication No. 2008/077430

However, in the conventional seawater flue gas desulfurization apparatus 107B, in the dilution mixing tank 132, bubbles containing a gas having a high SO ₂ concentration are formed by the filling of the bubbles by the sulfur component absorbing seawater 106A. Is absorbed into the dilution seawater 105B in the dilution mixing tank 132, so that the sulfur component absorbing seawater mixed with the dilution seawater 105B while containing the bubbles in the oxidation tank 133 open to the outdoors. the flows (106B), the SO ₂ is dissipated in the oxidation tank 133, there is a problem in that the risk emit the odor stimulus.

In addition, as in the conventional seawater flue gas desulfurization apparatus 107B, the seawater 105 using the flue gas desulfurization absorption tower 131 for dilution flows to the upper side of the dilution mixing tank 132 which becomes a drainage path of an unillustrated condenser. In a device in which seawater desulfurization and oxidation of the used seawater are integrated, the sulfur component absorbing seawater 106A and the seawater 105B supplied to the dilution mixing tank 132 are not sufficiently mixed by the temperature difference between them. There is a problem that it does not.

In addition, 106 A of sulfur component absorbing seawater flowing down the flue gas desulfurization absorption tower 131 falls into the dilute sea water path, so that bubbles containing SO ₂ are accumulated in the flue gas desulfurization absorption tower 131, and the flue gas desulfurization absorption is carried out. There is a problem that bubbles containing a high concentration of SO ₂ flows out of the tower 131.

In view of the above problems, the present invention provides a safe and reliable seawater flue gas desulfurization apparatus and a method for treating desulfurized seawater, which are prevented from dissipating SO ₂ recovered in seawater when oxidizing seawater used for desulfurization. Let's make it a task.

The 1st invention of this invention for solving the subject mentioned above is integrally provided in the flue gas desulfurization absorption tower which purifies the sulfur component in exhaust gas by contact with seawater, and the said flue gas desulfurization absorption tower, and is equipped with the said flue gas desulfurization absorption The tower has a dilution mixing tank for mixing and diluting the sulfur component absorbing seawater produced by contacting the sulfur component in the exhaust gas with the seawater and desulfurizing the seawater with the seawater supplied into the body, and the side wall of the flue gas desulfurization absorption tower. A lid part which is extended so as to cover the dilution mixing tank on the lower end side, and a first weir which is dripped from the back side of the lid part and whose end is buried in the water surface in the dilution mixing tank. It is a seawater flue gas desulfurization apparatus which has a gas retention part provided with.

2nd invention WHEREIN: 1st invention WHEREIN: The length L1 from the said side wall of the said flue gas desulfurization absorption tower to the inner wall of a said 1st dam satisfy | fills either of following formulas 1 and 2, and following formula (3). Seawater flue gas desulfurization apparatus characterized in that.

About bubble diameter dp in seawater,

Where d _G1 is the opening height from the first bank at the outlet of the gas reservoir to the bottom of the dilution mixing tank, τ ₁ is the residence time of the seawater in the gas reservoir, and U _t (dp) is the bubble diameter dp in the seawater. Is the terminal ascending velocity of the bubble group of, Cc is the SO ₂ environmental reference concentration, C ₀ is the SO ₂ concentration at the inlet of the flue gas desulfurization absorption tower of the exhaust gas, and Kg is the SO ₂ gas at the gas-liquid interface of the bubble. It is the overall mass transfer coefficient, dp is the bubble diameter, and U _L is the outlet flow rate at the bottom of the dilution mixing bath.

In addition, the terminal rise rate of the single bubble in a stationary fluid is calculated | required from the formula of the following Stokes of following formula (4), The larger the bubble, the faster the terminal rise rate.

Where g is gravity acceleration, dp is bubble diameter, ρ _L is seawater density, ρ _G is gas density, and μ is the viscosity of seawater.

If the bubble diameter exceeds 1 mm, the bubble shape does not become spherical due to friction with the fluid, and since the rising speed of the bubble group is different from the behavior of the single bubble, it does not strictly match, but in seawater The bubble diameter is usually about 0.5 to 1.0 mm, and even if it is large, it is rare to exceed 5.0 mm, and the terminal rise rate of the bubble group in seawater is 200 to 300 mm / s, and at most about 400 mm / s.

3rd invention is a seawater flue gas desulfurization apparatus characterized by providing a 2nd dam in the bottom part of the said dilution mixing tank in 1st invention.

4th invention WHEREIN: In length 3, length L2 from the said side wall of the said flue gas desulfurization absorption tower to the inner wall of a said 2nd dam satisfy | fills any of following formulas (5) and (7). It is in the seawater flue gas desulfurization apparatus characterized by the above-mentioned.

However, D is the liquid depth of the seawater of the dilution mixing tank, τ ₂ is the residence time of the seawater in the gas reservoir, U _t (dp) is the terminal rising rate of the bubble group of bubble diameter dp in the seawater, Cc is SO _{2 is the} environmental reference concentration, C ₀ is the concentration of SO ₂ at the inlet of the flue gas desulfurization absorption tower of the exhaust gas, Kg is the overall mass transfer coefficient of SO ₂ gas at the gas-liquid interface of bubbles, and dp is the bubble diameter. , U _L is the outlet flow rate at the bottom of the dilution mixing tank, and d _G2 is the height of the liquid level between the sea level and the second weir.

5th invention is a seawater flue gas desulfurization apparatus characterized by the above-mentioned 1st invention WHEREIN: The 3rd dam is provided inside the said gas retention part.

In a sixth invention, in the fifth invention, the length L3 from the outer wall of the third weir to the inner wall of the first weir satisfies any one of Equations 8 and 9 and Equation 10 below. Is in the seawater flue gas desulfurization unit.

Where d _G1 is the opening height from the first bank at the outlet of the gas reservoir to the bottom of the dilution mixing tank, τ ₃ is the residence time of the seawater in the gas reservoir, and U _t (dp) is the bubble diameter dp in the seawater. Is the terminal ascending velocity of the bubble group of, Cc is the SO ₂ environmental reference concentration, C ₀ is the SO ₂ concentration at the inlet of the flue gas desulfurization absorption tower of the exhaust gas, and Kg is the SO ₂ gas at the gas-liquid interface of the bubble. Is the overall mass transfer coefficient, dp is the bubble diameter, U _L is the outlet flow rate at the bottom of the dilution mixing tank, D is the liquid depth of the seawater in the dilution mixing tank, and d _G3 is between the end of the third weir and the bottom of the dilution mixing tank. Height, MIN (d _G1 , d _G3 ) is the minimum of d _G1 , d _G3 .

According to a seventh aspect of the present invention, in the first invention, a second dam is provided at the bottom of the dilution mixing tank, and a third dam is provided inside the gas reservoir.

 In the eighth invention, in the seventh invention, the length L4 from the outer wall of the third weir to the inner wall of the second weir satisfies any one of the following formulas (11) and (12). Is in the seawater flue gas desulfurization unit.

However, D is the liquid depth of the seawater of the dilution mixing tank, τ ₄ is the residence time of the seawater in the gas reservoir, U _t (dp) is the terminal rising rate of the bubble group of bubble diameter dp in the seawater, Cc is SO _{2 is the} environmental reference concentration, C ₀ is the concentration of SO ₂ at the inlet of the flue gas desulfurization absorption tower of the exhaust gas, Kg is the overall mass transfer coefficient of SO ₂ gas at the gas-liquid interface of bubbles, and dp is the bubble diameter. , U _L is the outlet flow rate at the bottom of the dilution mixing tank, d _G1 is the opening height from the first bank to the bottom of the dilution mixing tank, d _G2 is the height of the liquid level between the sea level and the second bank, and d _G3 is It is the height of the opening from 3 banks to the bottom of the dilution mixing tank, and MIN (d _G1 , d _G2 , d _G3 ) is the minimum value of d _G1 , d _G2 , d _G3 .

The ninth invention is the seawater according to any one of claims 5 to 8, wherein the third dam has an air hole communicating with the space between the gas reservoir and the seawater and the flue gas desulfurization absorption tower. It is in the flue gas desulfurization unit.

10th invention is seawater flue gas desulfurization apparatus in any one of 1st-9th invention whose said seawater is drainage discharged from a condenser.

The eleventh invention is one of the first to the tenth invention, provided in the downstream of the dilution mixing tank, oxidizing the sulfur component in seawater mixed with the sulfur component absorption seawater in the dilution mixing tank; It is a seawater flue gas desulfurization apparatus characterized by having an oxidizing tank which decarbonizes together and performs water quality recovery.

A twelfth invention uses a boiler, a steam turbine for driving a generator using steam generated using exhaust gas discharged from the boiler as a heat source for steam generation, and a condenser for recovering and circulating water condensed in the steam turbine. , A flue gas denitrification apparatus for performing denitrification of the exhaust gas discharged from the boiler, a dust collecting apparatus for removing dust in the exhaust gas, the seawater flue gas desulfurization apparatus according to any one of the first to eleventh embodiments, and the desulfurization purification in the flue gas desulfurization apparatus. The seawater desulfurization system is characterized by consisting of a chimney for discharging the gas to the outside.

A thirteenth invention is the liquid in the processing method of the desulfurization sea water, characterized in that to prevent from 1 to 11 using the water flue gas desulfurization apparatus of any of the invention in which the SO ₂ gas contained in the sea water used in the desulfurization dissipated to the outside have.

According to the present invention, a flue gas desulfurization absorption tower for purifying sulfur components in exhaust gas by contact with sea water, and a sulfur component absorbing seawater which is integrally provided under the flue gas desulfurization absorption tower and flows down from the flue gas desulfurization absorption tower. The connection portion of the dilution mixing tank for mixing with the seawater fed into the main body has a gas retention section having a lid portion having a constant length extended to cover the dilution mixing tank, and is received from the back side of the lid section, and the dilution mixing tank Since the end surface is buried in the inner surface of the water, the sulfur-containing absorbing seawater flows from the flue gas desulfurization absorption tower to contain a gas having a high SO ₂ concentration in the sulfur-containing absorbing seawater. A bubble is formed in a space in the gas reservoir formed by the lid and the first weir. To, it is possible to prevent the SO ₂ gas from leaking to outside.

As a result, when the seawater is oxidized to recover the water quality, the seawater containing SO ₂ can flow out into the oxidizing tank, thereby preventing SO _{2 from} being dissipated in the oxidizing tank of an open-air outdoor type, thereby preventing the irritating odor. And a highly reliable seawater flue gas desulfurization apparatus.

BRIEF DESCRIPTION OF THE DRAWINGS It is a schematic diagram which shows the structure of the seawater flue gas desulfurization apparatus which concerns on 1st Embodiment which concerns on this invention.
Fig. 2 is a schematic diagram showing a part of the configuration of the seawater flue gas desulfurization apparatus according to the first embodiment according to the present invention.
3 is a schematic view showing a part of the configuration of a conventional seawater flue gas desulfurization apparatus.
4 is a schematic view showing a part of the configuration of a seawater flue gas desulfurization apparatus according to a second embodiment according to the present invention.
Fig. 5 is a schematic view showing a part of the configuration of the seawater flue gas desulfurization apparatus according to the third embodiment of the present invention.
6 is a partially enlarged view of the configuration of the seawater flue gas desulfurization apparatus according to the third embodiment according to the present invention.
Fig. 7 is a schematic diagram showing a part of the configuration of the seawater flue gas desulfurization apparatus according to the fourth embodiment according to the present invention.
8 is a conceptual diagram illustrating a seawater desulfurization system.
9 is a view showing an example of a flowchart of a thermal power generation system having a seawater flue gas desulfurization apparatus using conventional seawater.
10 is a view briefly showing another configuration of the seawater flue gas desulfurization apparatus applied to the conventional seawater desulfurization system.

EMBODIMENT OF THE INVENTION Hereinafter, this invention is demonstrated concretely, referring drawings. In addition, this invention is not limited by this embodiment. In addition, the component in the following embodiment includes the thing which a person skilled in the art can easily assume, or the substantially same thing.

[First Embodiment]

EMBODIMENT OF THE INVENTION The seawater flue gas desulfurization apparatus which concerns on 1st Embodiment which concerns on this invention is demonstrated with reference to drawings.

BRIEF DESCRIPTION OF THE DRAWINGS It is a schematic diagram which shows the structure of the seawater flue gas desulfurization apparatus which concerns on 1st Embodiment which concerns on this invention, and FIG. 2 is a schematic diagram which shows a part of the structure of the seawater flue gas desulfurization apparatus shown in FIG.

As shown in FIG. 1, the 1st seawater flue gas desulfurization apparatus 10-1 which concerns on this embodiment contacts the sulfur component in the exhaust gas 11 with 12A of absorption seawater which is a part of seawater 12, and it purifies. The flue gas desulfurization absorption tower 13 and the flue gas desulfurization absorption tower 13 are integrally provided, and the sulfur component in the exhaust gas 11 is absorbed by the flue gas desulfurization absorption tower 13. And dilution mixing tank 16 for mixing and diluting the sulfur component absorbing seawater 14A flowing in the flue gas desulfurization absorption tower 13 generated by seawater desulfurization in contact with the dilution with the dilution seawater 12B fed into the main body 15. In addition, the lid portion 18 extended along the long direction of the dilution mixing tank 16 so as to cover the dilution mixing tank 16 on the lower end side of the side wall 17 of the flue gas desulfurization absorption tower 13, The 1st bank 19 which is dripped from the back surface side of this lid part 18, and the edge part 19a is buried in the sea surface in the water surface in the dilution mixing tank 16 is calculated | required. The gas to have a retention section (20A).

In addition, in the figure, code | symbol 16a is the bottom part of the dilution mixing tank 16. As shown in FIG.

In the present embodiment, the seawater 12 is supplied to the flue gas desulfurization absorption tower 13 among the sea water 12 and used for purification of the exhaust gas 11 as the absorbing sea water 12A. The seawater used for feeding is used as dilution seawater 12B. In addition, the seawater in which the seawater 12B for dilution and the sulfur component absorption seawater 14A flowing down in the flue gas desulfurization absorption tower 13 in the flue gas desulfurization absorption tower 13 are mixed is used as the sulfur component absorption seawater 14B.

The absorption seawater 12A used in the flue gas desulfurization absorption tower 13 is a pump 24 among the seawater 12 pumped from the sea 21 to the seawater supply line 23 using the pump 22. Absorption seawater 12A, which is a part of the seawater 12 extracted by NF, is fed to the flue gas desulfurization absorption tower 13. In addition, although the seawater 12 uses the seawater directly pumped up by the pump 22 from the sea 21, this invention is not limited to this, The seawater 12 discharged from the condenser which is not shown in figure is shown. The drainage may be used.

In the flue gas desulfurization absorption tower 13, the exhaust gas 11 and the absorbing seawater 12A are gas-liquid contacted to desulfurize the sulfur component in the exhaust gas 11. That is, in the flue gas desulfurization absorption tower 13, the exhaust gas 11 and the absorbing seawater 12A are gas-liquid contacted to cause a reaction as shown in the following reaction formula to form a form such as SO ₂ in the exhaust gas 11. Sulfur components such as sulfur oxides (SO _X ) contained in the water are removed using the absorbing sea water 12A.

[Reaction Scheme I]

_{SO 2 (g) + H 2} O → H 2 SO 3 (l) → HSO 3 - + H +

H ₂ SO ₃ generated by the gas-liquid contact between the absorbing seawater 12A and the exhaust gas 11 by this seawater desulfurization dissociates and H ⁺ is released into the absorbing seawater 12A. A large amount of sulfur is absorbed into the sulfur component absorbing seawater 14A flowing down the desulfurization absorption tower 13. At this time, the pH of the sulfur component absorbing seawater 14A flowing down the flue gas desulfurization absorption tower 13 is, for example, about 3. The sulfur component absorbing seawater 14A flows down the inside of the flue gas desulfurization absorption tower 13 and is collected in the dilution mixing tank 16 which is integrally provided under the flue gas desulfurization absorption tower 13. In addition, the purge gas 25 desulfurized in the flue gas desulfurization absorption tower 13 is discharged to the atmosphere through the purge gas discharge passage 26.

In addition, a part of the seawater 12 is supplied from the seawater supply line 23 to the dilution mixing tank 16 through the dilution seawater supply line 27 as the dilution seawater 12B. In the dilution mixing tank 16, the sulfur component absorbing seawater 14A flowing down the inside of the flue gas desulfurization absorption tower 13 is mixed with the dilution seawater 12B and diluted. The seawater in which the sulfur component absorbing seawater 14A and the dilution seawater 12B flowing down in the flue gas desulfurization absorption tower 13 is mixed is used as the sulfur component absorbing seawater 14B. By mixing and diluting the sulfur component absorbing seawater 14A with the seawater 12B, the pH of the sulfur component absorbing seawater 14B in the dilution mixing tank 16 can be raised to prevent the re-dispersion of SO ₂ .

2 is a schematic diagram which shows a part of structure of the seawater flue gas desulfurization apparatus which concerns on this embodiment briefly. As shown in FIG. 2, the 1st seawater flue gas desulfurization apparatus 10-1 which concerns on this embodiment is a dilution mixing tank at the lower end side of the side wall 17 of the dilution mixing tank downstream of the flue gas desulfurization absorption tower 13. The first bank that is closed from the back surface side of the lid portion 18 and the lid portion 18 that has been extended so as to cover 16, and whose end portion 19a is buried in the sea surface in the water surface in the dilution mixing tank 16. 20 A of gas retention parts provided with 19 are provided. Then, the first dam 19 is received from the gas reservoir 20A, and the sulfur component in which the dilute seawater 12B and the sulfur component absorbing seawater 14A flowing down the inside of the flue gas desulfurization absorption tower 13 are mixed. A part of the absorbing seawater 14B is blocked in the flue gas desulfurization absorption tower 13.

The sulfur component absorbing seawater 14A flows down from the flue gas desulfurization absorption tower 13 so that the bubble 28 containing the gas having a high SO ₂ concentration in the flue gas desulfurization absorption tower 13 is rolled up in the sulfur component absorption seawater 14B. Will be heard. The bubble 28 containing the SO ₂ gas entrained in the sulfur component absorbing seawater 14B is formed in the space S1 formed by the lid 18 and the first weir 19 of the gas reservoir 20A. Dissipates within. For this reason, the SO ₂ gas entrained in the sulfur component absorbing seawater 14B can be stopped in the space S1 formed by the lid 18 and the first weir 19 of the gas reservoir 19B. .

FIG. 3 is a schematic diagram schematically showing a part of the configuration of the conventional seawater flue gas desulfurization apparatus shown in FIG. 10. The conventional seawater flue gas desulfurization apparatus 107B shown in FIG. 3 extends the dilution mixing tank downstream wall plate of the flue gas desulfurization absorption tower 131 to the sulfur component absorbing seawater 106B of the dilution mixing tank 132 as it is, and dilutes it. The end part is buried in the water surface in the mixing tank 132. For this reason, in the conventional seawater flue gas desulfurization apparatus 107B, by the bubble of the sulfur component absorbing seawater 106A flowing down the inside of the flue gas desulfurization absorption tower 131, it is rolled up in the dilution seawater 105B. Bubbles containing a gas having a high SO ₂ concentration rise to dissipate out of the flue gas desulfurization absorption tower 131, and there is a fear that the SO ₂ gas leaks to the outside.

On the other hand, in this embodiment, the lid part 18 extended so that the dilution mixing tank 16 may be covered by the lower end side of the side wall 17 of the flue gas desulfurization absorption tower 13, and the lid part 18 of The gas retention part 20A provided with the 1st bank 19 which is dripped from the back surface side, and the edge part is buried in the water surface in the dilution mixing tank 16, and the edge part 19a of the 1st bank 19 is provided. Is buried in the water surface in the dilution mixing tank 16, and partially immersed in the sulfur component absorption seawater 14B in the main body 15. As shown in FIG. Therefore, the air bubbles 28 that sulfur absorption water (14A) is by gwonip of the bubble 28 due to fluid flowing down from the flue gas desulfurization absorber 13, including the SO ₂ concentration higher gas is sulfur absorbed water Even if it is rolled up to 14B, the bubble 28 containing SO ₂ gas entrained in the sulfur component absorbing seawater 14B is applied to the lid 18 and the first weir 19 of the gas reservoir 20A. It can dissipate in space S1 formed by this. As a result, the SO ₂ gas can be stopped in the space S1 formed by the lid 18 and the first weir 19 of the gas reservoir 19B, thereby preventing the SO ₂ gas from leaking to the outside. .

As a result, as will be described later, when the sulfur component absorbing seawater 14B flows through the open-type oxidation tank 29, the bubble 28 containing SO ₂ gas which is dried in the dilution mixing tank 16 flows and is oxidized. SO ₂ is dissipated to the tank 29, and leakage to the outside can be prevented, and the irritation odor can be prevented.

In the present embodiment, the length L1 from the side wall 17 of the flue gas desulfurization absorption tower 13 to the inner wall 19b of the first weir 19 is equal to either of the following equations (1) and (2). The following Equation 3 is satisfied.

[Equation 1]

d _G1 <τ ₁ U _t (dp)

&Quot; (2) &quot;

Cc> C ₀ exp (-6 Kg / dpτ ₁ )

&Quot; (3) &quot;

τ ₁ = L1 / U _L

Where d _G1 is the opening height from the first bank at the outlet of the gas reservoir to the bottom of the dilution mixing tank, τ ₁ is the residence time of the seawater in the gas reservoir, and U _t (dp) is the bubble diameter dp in the seawater. Is the terminal ascending velocity of the bubble group of, Cc is the SO ₂ environmental reference concentration, C ₀ is the SO ₂ concentration at the inlet of the flue gas desulfurization absorption tower of the exhaust gas, and Kg is the SO ₂ gas at the gas-liquid interface of the bubble. It is the overall mass transfer coefficient, dp is the bubble diameter, and U _L is the outlet flow rate at the bottom of the dilution mixing bath.

Here, the terminal rising speed U _t of the single bubble in the stationary fluid is obtained from Equation 4 of the following Stokes, and the larger the bubble, the faster the terminal rising speed.

&Quot; (4) &quot;

U _t = g × dp ² × (ρ _L -ρ _G ) / 18μ

Where g is gravity acceleration, dp is bubble diameter, ρ _L is seawater density, ρ _G is gas density, and μ is the viscosity of seawater.

If the bubble diameter exceeds 1 mm, the bubble shape does not become spherical due to friction with the fluid, and since the rising speed of the bubble group is different from the behavior of the single bubble, it does not strictly match, but in seawater The bubble diameter is usually about 0.5 to 1.0 mm, and rarely exceeds 5.0 mm, and the terminal rising velocity U _t of the bubble group in seawater is 200 to 300 mm / s, at most about 400 mm / s.

By satisfying the above formula as in the present embodiment, among the bubbles 28 containing SO ₂ gas entrained in the sulfur component absorbing seawater 14B, a relatively large bubble having a high floating rate is more reliably gas retained ( In the space S1 formed by the lid 18 and the first weir 19 of 20A, the SO ₂ gas can be dissipated. In addition, it is possible to absorb the sulfur component absorbed water (14B) to dry the SO ₂ gas bubbles (28), an injury rate is low relatively small bubbles SO ₂ gas to the sulfur content absorbed water (14B) of which comprises a picked during.

For this reason, the bubble 28 containing the SO ₂ gas rolled up in the dilution mixing tank 16 flows to the oxidation tank 29 with the sulfur component absorption seawater 14B, and SO ₂ flows into the oxidation tank 29. It can dissipate and prevent a stimulus smell.

Thereby, as will be described later, the gas generated when the water quality recovery of the sulfur component absorbing seawater 14B is performed in the oxidizing tank 29 dissipates to the oxidizing tank 29 so as to satisfy the SO ₂ environmental standard concentration. You can.

Therefore, the bubble 28 containing the high concentration SO ₂ gas rolled up in the dilution mixing tank 16 is dissipated in the oxidation tank 29 provided on the downstream side of the dilution mixing tank 16, and SO ₂ It is possible to prevent the gas from leaking to the outside, thereby providing a safe and reliable seawater desulfurization absorber.

 And after the bubble 28 in the sulfur component absorption seawater 14B dissipates in the dilution mixing tank 16, the sulfur component absorption seawater 14B is oxidized in the downstream of the dilution mixing tank 16 ( 29). In addition, in this embodiment, although it consists of one tank integrally with the dilution mixing tank 16 and the oxidation tank 29, this invention is not limited to this, The dilution mixing tank 16 and the oxidation tank ( 29 may be used as the respective tanks to connect the dilution mixing tank 16 and the oxidation tank 29.

The oxidation tank 29 is integrally provided at the downstream side of the dilution mixing tank 16, oxidizes and decarbonates the sulfur component in the sulfur component absorbing seawater 14B to restore water quality. The air supply part 30 is provided in the oxidation tank 29. The air supply unit 30 includes an oxidation air blower 32 for supplying air 31, an air diffuser 33 for supplying air 31, and a sulfur component of the air 31 in the oxidation tank 29. It consists of the nozzle 34 for oxidizing air supplied to the absorption seawater 14B. In the oxidizing tank 29, the air 31 is sent to the oxidizing tank 29 from the nozzle 34 for oxidizing air through the diffuser 33 by the oxidizing air blower 32, and the oxidizing tank 29 The sulfur component in contact with air 31 causes dissolution of oxygen, oxidation of sulfurous acid, and decarbonation reaction as in the following reactions II to V.

[Reaction Scheme II]

O ₂ (g) → O ₂ (l)

[Reaction Scheme III]

^{_{HSO 3 - + 1/2 O 2 →}} SO 4 2- + H +

[Reaction Scheme IV]

_{^{HCO 3 - + H + → CO}} 2 (g) + H 2 O

[Reaction Scheme V]

CO ₃ ^2- + 2 H ⁺ → CO ₂ (g) + H ₂ O

The sulfur component absorbing seawater 14B is oxidized by the oxidation reaction of hydrogen sulfite ions (HSO ₃ ⁻ ) in the sulfur component absorbing seawater 14 and the decarbonation reaction of bicarbonate ions (HCO ₃ ⁻ ). The water quality is restored and becomes the water quality recovery seawater 35.

The water quality recovery seawater 35 is discharged to the sea 21 as seawater waste liquid through the seawater discharge line 36. Thereby, while raising the pH of the water quality modified seawater 35, COD can be reduced, and the pH, dissolved oxygen concentration, and COD of the water quality recovery seawater 35 can be discharged at a level where seawater can be discharged. .

Thus, according to the 1st seawater flue gas desulfurization apparatus 10-1 which concerns on this embodiment, the flue gas desulfurization absorption tower 13 which purifies the sulfur component in the exhaust gas 11 by contacting seawater 12A, and the said, The sulfur component absorbing seawater 14A formed integrally under the flue gas desulfurization absorption tower 13 and desulfurized by seawater desulfurization in the flue gas desulfurization absorption tower 13 is mixed with the dilution seawater 12B fed into the main body 15. A dilution mixing tank 16 to be diluted, a lid portion 18 extending to cover the dilution mixing tank 16 on the lower end side of the side wall 17 of the flue gas desulfurization absorption tower 13, and the lid portion 18. It has a gas retention part 20A provided with the 1st bank 19 in which water is dripped from the back surface side of () and the edge part 19a is buried in the water surface in the dilution mixing tank 16. As shown in FIG. The first bank 19 drops off from the back surface side of the lid 18, and the end portion 19a is buried in the water surface in the dilution mixing tank 16, and a part of the sulfur component absorbing seawater 14B is flue gas desulfurized. The absorption tower 13 is to be blocked. Therefore, the gas reservoir portion 20A includes a bubble 28 containing a gas having a high SO ₂ concentration, which is caused by the sulfur component absorbing seawater 14A flowing down from the flue gas desulfurization absorption tower 13 to be incorporated into the sulfur component absorbing seawater 14B. It is dissipated in the space S1 formed by the lid portion 18 and the first weir 19 of the (), so that the SO ₂ gas can be prevented from leaking to the outside.

As a result, when the sulfur component-absorbing seawater 14B flowing in the open-type oxidation tank 29 is oxidized and water quality recovery is performed, the bubble 28 containing SO ₂ gas dried in the dilution mixing tank 16 is recovered. The gas flows through the oxidation tank 29 to be dissipated, and the SO ₂ can be prevented from leaking to the outside, and the irritating odor can be prevented, thereby providing a safe and reliable seawater flue gas desulfurization apparatus.

In addition, in this embodiment, although the seawater flue gas desulfurization apparatus which processes the seawater which used the oxidizing tank 29 for seawater desulfurization in the flue gas desulfurization absorption tower 13 was demonstrated, this invention is not limited to this. The oxidation tank 29 is, for example, sulfur generated by desulfurization of sulfur oxides contained in exhaust gases discharged from power plants such as plants in various industries, power plants such as large and medium-sized thermal power plants, large boilers for electric businesses, or general industrial boilers. It can be used for removal of the sulfur component in the component absorption seawater 14A and desulfurization seawater.

[Second Embodiment]

Next, the seawater flue gas desulfurization apparatus according to the second embodiment of the present invention will be described with reference to FIG. 4.

Since the structure of the seawater flue gas desulfurization apparatus is the same as that of the seawater flue gas desulfurization apparatus according to the first embodiment of the present invention, the schematic diagram of the whole seawater flue gas desulfurization apparatus according to the above embodiment is omitted, and the seawater flue gas according to the above embodiment is omitted. About the same structure as a desulfurization apparatus, the same code | symbol is attached | subjected and the description which overlaps is abbreviate | omitted.

4 is a schematic view schematically showing a part of the configuration of the seawater flue gas desulfurization apparatus according to the present embodiment. As shown in FIG. 4, the 2nd seawater flue gas desulfurization apparatus 10-2 which concerns on this embodiment dilutes the 1st seawater flue gas desulfurization apparatus 10-1 which concerns on 1st embodiment shown in FIGS. It has the gas retention part 20B which provided the 2nd bank 42 in the bottom part 16a of the mixing tank 16. As shown in FIG.

As in the present embodiment, by providing the second weir 42 at the bottom 16a of the dilution mixing tank 16, between the liquid level of the sulfur component absorbing seawater 14B and the end 42a of the second weir 42 The height (d _G2 ) of the liquid level becomes low. For this reason, the flow velocity of the sulfur component absorbing seawater 14B which flows through the oxidizing tank 29 is accelerated | evaporated, and the bubble 28 in the sulfur component absorbing seawater 14B is made into the liquid level of the sulfur component absorbing seawater 14B, and the 2nd bank ( It can be concentrated between the ends 42a of 42. As a result, the bubble 28 can be dissipated in the space S1 formed by the lid 18 and the first weir 19 of the gas reservoir 20B.

Thereby, the bubble 28 containing the SO ₂ gas rolled up in the dilution mixing tank 16 flows into the oxidation tank 29 to dissipate SO ₂ , thereby preventing the SO ₂ gas from leaking to the outside, It can prevent the smell of irritating.

In addition, when the sulfur component absorption seawater 14A which is a desulfurization falling liquid in the dilution mixing tank 16 is mixed with the dilution seawater 12B, the sulfur component absorption seawater 14A is in contact with the exhaust gas 11. Therefore, since the liquid temperature is high and the dilution seawater 12B has a low liquid temperature, it is difficult to mix uniformly by simply joining. In this embodiment, since the 2nd bank 42 is provided in the bottom part 16a of the dilution mixing tank 16, the liquid level of the sulfur component absorption seawater 14B and the edge part 42a of the 2nd bank 42 are provided. The height d _G2 of the liquid surface in between is low, and the flow rate of the sulfur component absorbing seawater 14B flowing through the oxidizing tank 29 can be increased. For this reason, mixing of the sulfur component absorption seawater 14A and the dilution seawater 12B can be promoted.

In the present embodiment, the length L ₂ in the flow direction of the sulfur component absorbing seawater 14B from the side wall 17 of the flue gas desulfurization absorption tower 13 to the inner wall 42b of the second weir 42. ) Satisfies any one of the following expressions (5) and (7).

[Equation 5]

D <τ ₂ U _t (dp)

&Quot; (6) &quot;

Cc> C ₀ exp (-6 Kg / dpτ ₂ )

[Equation 7]

τ ₂ = L2 / (U _L × D / d _G2 )

However, D is the liquid depth of the seawater of the dilution mixing tank, τ ₂ is the residence time of the seawater in the gas reservoir, U _t (dp) is the terminal rising rate of the bubble group of bubble diameter dp in the seawater, Cc is SO _{2 is the} environmental reference concentration, C ₀ is the concentration of SO ₂ at the inlet of the flue gas desulfurization absorption tower of the exhaust gas, Kg is the overall mass transfer coefficient of SO ₂ gas at the gas-liquid interface of bubbles, and dp is the bubble diameter. , U _L is the outlet flow rate at the bottom of the dilution mixing tank, and d _G2 is the height of the liquid level between the sea level and the second weir.

As in the present embodiment, by satisfying the above equation, the bubble 28 containing the SO ₂ gas in the sulfur component absorbing seawater 14B is more reliably provided by the gas reservoir 20B and the first weir 19. to dissipate into the formed space (S1), it is possible to dissipate the SO ₂ gas. Thereby, the bubble 28 containing the SO ₂ gas rolled up in the dilution mixing tank 16 flows to the oxidation tank 29 with the sulfur component absorption seawater 14B, and SO ₂ flows into the oxidation tank 29. It can dissipate and prevent a stimulus smell.

As a result, as described above, the gas generated when the water quality recovery of the sulfur component absorbing seawater 14B is performed in the oxidizing tank 29 satisfies the SO ₂ environmental standard concentration. It can dissipate.

Therefore, according to the 2nd seawater flue gas desulfurization apparatus 10-2 which concerns on this embodiment, the sulfur which flows through the oxidation tank 29 by providing the 2nd bank 42 in the bottom part 16a of the dilution mixing tank 16 is carried out. The flow rate of the component absorbing seawater 14B is accelerated, the bubbles 28 are concentrated on the upper surface of the liquid, and the dilution mixing tank 16 promotes mixing of the sulfur component absorbing seawater 14A and the dilution seawater 12B. At the same time, the bubbles 28 in the sulfur component absorbing seawater 14B can be dispersed in the space S1 formed by the lid 18 and the first weir 19 of the gas reservoir 20B. To this end, the air bubbles 28 containing the SO ₂ gas rolled in a dilution mixing chamber 16 is prevented from SO ₂ gas from leaking to the outside from the oxidation tank 29 flows into the oxidation tank 29, a safety And a highly reliable seawater flue gas desulfurization apparatus.

[Third embodiment]

Next, the seawater flue gas desulfurization apparatus according to the third embodiment of the present invention will be described with reference to FIGS. 5 and 6.

Since the structure of the seawater flue gas desulfurization apparatus is the same as that of the seawater flue gas desulfurization apparatus according to the first embodiment of the present invention, the schematic diagram of the whole seawater flue gas desulfurization apparatus according to the above embodiment is omitted, and the seawater flue gas according to the above embodiment is omitted. About the same structure as a desulfurization apparatus, the same code | symbol is attached | subjected and the description which overlaps is abbreviate | omitted.

5 is a schematic view showing a part of the configuration of the seawater flue gas desulfurization apparatus according to the present embodiment, and FIG. 6 is a partially enlarged view of the configuration of the seawater flue gas desulfurization apparatus according to the present embodiment.

Here, in the tower of the flue gas desulfurization absorption tower 13 which is a seawater desulfurization absorption tower, since a large amount of sulfur component absorption seawater 14A which is a seawater falling-off liquid falls on the dilution mixing tank 16 which is a dilution seawater, a large amount of foam It has been confirmed that this occurs. It is confirmed that the amount of bubbles generated depends on the quality of the seawater and the concentration of SO ₂ gas in the exhaust gas 11. When a large amount of bubbles is generated, the dilution mixing tank 16 inside the flue gas desulfurization absorption tower 13 is used. Is covered with bubbles, and there is a possibility of outflow to the outside by the flow of the sulfur component absorbing seawater 14B.

As shown in FIG. 5, the 3rd seawater flue gas desulfurization apparatus 10-3 which concerns on this embodiment provides the gas retention part 20C which provided the 3rd bank 43 inside the gas retention part 20C. The third weir 43 is dripped from the back surface side of the lid part 18, and the edge part 43a is buried in the water surface in the dilution mixing tank 16, and the seawater 12B and the sulfur component absorption seawater ( Part of the seawater 12C mixed with 14 is blocked in the flue gas desulfurization absorption tower 13 to prevent the outflow of bubbles generated inside the flue gas desulfurization absorption tower 13 which is the absorption tower.

Dilution mixing by blocking the flow of a part of the sulfur component absorption seawater 14B by burying the end 43a of the third weir 43 received from the back surface side of the lid 18 on the water surface in the dilution mixing tank 16. The tank 16 promotes mixing of the sulfur component absorbing seawater 14A and the dilution seawater 12B to cover the lid 18, the first weir 19, and the third weir 43 of the gas reservoir 20C. Bubbles 28 are dissipated in the space S2 formed by) to prevent SO ₂ gas from leaking to the outside, and the outflow of bubbles generated inside the flue gas desulfurization absorption tower 13 can be prevented. This prevents the bubble 28 containing the SO ₂ gas rolled up in the dilution mixing tank 16 from flowing into the oxidizing tank 29 to prevent the SO ₂ gas from leaking to the outside, thereby producing an irritating odor. can do.

In addition, in this embodiment, as shown to FIG. 5, 6, the lid part 18 of the gas retention part 20C, the 1st bank 19, and the 3rd bank 43 are attached to the 3rd bank 43. As shown in FIG. The ventilation hole 44 which communicates the space S2 formed with the gas and the flue gas desulfurization absorption tower 13 is provided. Therefore, the SO ₂ gas filled in the space S2 formed by the lid 18 of the gas reservoir 20B, the first weir 19 and the third weir 43 is directed to the flue gas desulfurization absorption tower 13. It can dissipate.

In the present embodiment, the height d _G3 between the end 43a of the third weir 43 and the bottom face 16a of the dilution mixing tank 16 is the end 19a of the first weir 19. And the same height as the height d _G1 between the bottom face 16a of the dilution mixing tank 16, but the present invention is not limited to this and may be different.

In the present embodiment, the length L3 in the flow direction of the seawater 12C from the outer wall 43b of the third weir 43 to the inner wall 41a of the first weir 19 is represented by the following mathematical expression. Either of Formulas 8 and 9 and Expression 10 below are satisfied.

[Equation 8]

d _G1 <τ ₃ U _t (dp)

&Quot; (9) &quot;

Cc> C ₀ exp (-6 Kg / dpτ ₃ )

&Quot; (10) &quot;

τ ₃ = L3 / (U _L × D / MIN (d _G1 , d _G3 ))

Where d _G1 is the opening height from the first bank at the outlet of the gas reservoir to the bottom of the dilution mixing tank, τ ₃ is the residence time of the seawater in the gas reservoir, and U _t (dp) is the bubble diameter dp in the seawater. Is the terminal ascending velocity of the bubble group of, Cc is the SO ₂ environmental reference concentration, C ₀ is the SO ₂ concentration at the inlet of the flue gas desulfurization absorption tower of the exhaust gas, and Kg is the SO ₂ gas at the gas-liquid interface of the bubble. Is the overall mass transfer coefficient, dp is the bubble diameter, U _L is the outlet flow rate at the bottom of the dilution mixing vessel, D is the liquid depth of the seawater in the dilution mixing vessel, and d _G3 is between the end of the third weir and the bottom of the dilution mixing vessel. Height, MIN (d _G1 , d _G3 ) is the minimum of d _G1 , d _G3 .

As in the present embodiment, by satisfying the above equation, the bubble 28 containing the SO ₂ gas in the sulfur component absorbing seawater 14B is more reliably covered with the lid 18 and the first of the gas reservoir 20C. It is possible to dissipate in the space S2 formed by the weir 19 and the third weir 43. Thereby, the bubble 28 containing the SO ₂ gas rolled up in the dilution mixing tank 16 flows to the oxidation tank 29 together with the sulfur component absorbing seawater 14B, and SO ₂ is released from the oxidation tank 29. It can dissipate and prevent leakage to the outside, thereby preventing the irritating smell from being emitted.

As a result, as described above, the gas generated when the water quality recovery of the sulfur component absorbing seawater 14B is performed in the oxidizing tank 29 satisfies the SO ₂ environmental standard concentration, thereby dissipating in the oxidizing tank 29. You can.

Therefore, according to the 3rd seawater flue gas desulfurization apparatus 10-3 which concerns on this embodiment, the 3rd embankment 43 is provided inside the gas retention part 20C of the flow direction of the sulfur component absorption seawater 14B, The height of the liquid level between the bottom part 16a of the dilution mixing tank 16 and the 3rd bank 43 is made low. Thereby, the mixing of the sulfur component absorbing seawater 14A and the dilution seawater 12B in the dilution mixing tank 16 is promoted, and the lid portion 18 and the first weir 19 of the gas reservoir 20C. And the bubbles 28 in the space S2 formed by the third weir 43 to prevent SO ₂ gas from leaking to the outside and to prevent bubbles from occurring inside the flue gas desulfurization absorption tower 13. Prevent spills. Because of this, it is possible to prevent curling picked the bubble 28 in a dilution mixing tank 16 to SO ₂ gas is leaked to the outside from the oxidation tank 29, the oxidation tank 29 flows to, high safety and reliability A seawater flue gas desulfurization apparatus can be provided.

[Fourth Embodiment]

Next, a seawater flue gas desulfurization apparatus according to a fourth embodiment of the present invention will be described with reference to FIG. 7.

Since the structure of the seawater flue gas desulfurization apparatus is the same as that of the seawater flue gas desulfurization apparatus according to the first embodiment of the present invention, the schematic diagram of the whole seawater flue gas desulfurization apparatus according to the above embodiment is omitted, and the seawater flue gas according to the above embodiment is omitted. About the same structure as a desulfurization apparatus, the same code | symbol is attached | subjected and the description which overlaps is abbreviate | omitted.

 Fig. 7 is a schematic diagram schematically showing a part of the configuration of the seawater flue gas desulfurization apparatus according to the present embodiment. As shown in FIG. 7, the seawater flue gas desulfurization apparatus 10-4 which concerns on 4th Embodiment which concerns on this embodiment is the 1st seawater flue gas desulfurization which concerns on 1st Embodiment by this invention shown in FIG. The apparatus 10-1, the 2nd seawater flue gas desulfurization apparatus 10-2 which concerns on 2nd embodiment by this invention shown in FIG. 4, and the agent which concerns on 3rd embodiment by this invention shown in FIG. It combines 3 seawater flue gas desulfurization apparatus 10-3.

That is, as shown in FIG. 7, the 4th seawater flue gas desulfurization apparatus 10-4 which concerns on this embodiment uses the dilution mixing tank 16 in the lower end side of the side wall 17 of the flue gas desulfurization absorption tower 13. The first weir 19 which is dripped from the back surface side of the lid part 18 extended along the longitudinal direction of the dilution mixing tank 16 so that the edge part 19a may be buried in the water surface in the dilution mixing tank 16 is covered. And the second weir 42 on the bottom portion 16a of the dilution mixing tank 16, and the water surface in the dilution mixing tank 16 inside the lid part 18 from the back side of the lid part 18. It has the gas retention part 20C provided with the 3rd bank 43 which the edge part 43a embeds in it, The 1st bank 19 and the 3rd bank 43 drop off from the lid part 18, In the flue gas desulfurization tank 13, a part of the sulfur component absorbing seawater 14B in which the dilution seawater 12B and the sulfur component absorbing seawater 14A are mixed is blocked.

The first bank 19 received from the back surface side of the lid 18 of the gas reservoir 20D is provided, and the second bank 42 is provided at the bottom 16a of the dilution mixing tank 16. At the same time, by providing the third weir 43 received from the back surface side of the lid portion 18, the oxidation tank (while promoting the mixing of the sulfur component absorbing seawater 14A and the dilution seawater 12B as described above). The flow rate of the sulfur component absorbing seawater 14B flowing toward 29 is increased, and the bubble 28 containing SO ₂ gas in the sulfur component absorbing seawater 14B in the dilution mixing tank 16 is transferred to the gas reservoir 20D. It is possible to dissipate into the space (S2) formed by the first weft (19) and the third weir (43).

In the present embodiment, the length L4 from the outer wall 43b of the third weir 43 to the inner wall 42b of the second weir 42 is defined by either of the following Equations 11 and 12. Equation 13 is satisfied.

&Quot; (11) &quot;

D <τ ₄ U _t (dp)

&Quot; (12) &quot;

Cc> C ₀ exp (-6 Kg / dpτ ₄ )

&Quot; (13) &quot;

τ ₄ = L4 / (U _L × D / MIN (d _G1 , d _G2 , d _G3 ))

However, D is the liquid depth of the seawater of the dilution mixing tank, τ ₄ is the residence time of the seawater in the gas reservoir, U _t (dp) is the terminal rising rate of the bubble group of bubble diameter dp in the seawater, Cc is SO _{2 is the} environmental reference concentration, C ₀ is the concentration of SO ₂ at the inlet of the flue gas desulfurization absorption tower of the exhaust gas, Kg is the overall mass transfer coefficient of SO ₂ gas at the gas-liquid interface of bubbles, and dp is the bubble diameter. , U _L is the outlet flow rate at the bottom of the dilution mixing tank, d _G1 is the opening height from the first bank to the bottom of the dilution mixing tank, d _G2 is the height of the liquid level between the sea level and the second bank, and d _G3 is It is the height of the opening from 3 banks to the bottom of the dilution mixing tank, and MIN (d _G1 , d _G2 , d _G3 ) is the minimum of d _G1 , d _G2 , d _G3 .

As in the present embodiment, by satisfying the above equation, the bubble 28 containing the SO ₂ gas entrained in the sulfur component absorbing seawater 14B is more reliably provided in the first bank of the gas reservoir 20D. It is possible to dissipate in the space S2 formed by the 19 and the third weir 43. Thereby, the bubble 28 containing the SO ₂ gas rolled up in the dilution mixing tank 16 flows to the oxidation tank 29 together with the sulfur component absorbing seawater 14B, and SO ₂ is released from the oxidation tank 29. Dissipation to the outside is prevented from leaking, and it is possible to prevent the irritating smell from being emitted.

As a result, as described above, the gas generated when the water quality recovery of the sulfur component absorbing seawater 14B is performed in the oxidizing tank 29 satisfies the SO ₂ environmental standard concentration, thereby dissipating in the oxidizing tank 29. You can.

Therefore, according to the fourth seawater flue gas desulfurization apparatus 10-4 according to the present embodiment, the dilution mixing tank 16 further promotes the mixing of the sulfur component absorbing seawater 14A and the dilution seawater 12B. At the same time, the bubbles 28 in the sulfur component absorbing seawater 14B can be dispersed in the space S2 formed of the first weir 19 and the third weir 43 of the gas reservoir 20D. Thereby, the bubble 28 containing the SO ₂ gas rolled up in the dilution mixing tank 16 flows, and SO ₂ flows outward in the oxidizing tank 29 so that the SO ₂ gas flows outward in the oxidizing tank 29. It is possible to more reliably prevent leakage, thereby providing a seawater flue gas desulfurization apparatus with high safety and reliability.

[Fifth Embodiment]

Next, the seawater desulfurization system according to the fifth embodiment using the seawater flue gas desulfurization apparatus of the present invention will be described with reference to FIG. 8.

8 is a conceptual diagram illustrating a seawater desulfurization system. Since the structure of a seawater flue gas desulfurization apparatus is the same as that of the seawater flue gas desulfurization apparatus by 1st Embodiment-5th Embodiment of this invention, description is abbreviate | omitted here.

As shown in FIG. 8, the seawater desulfurization system 50 which concerns on this embodiment burns the boiler 53 by the burner which is not shown in figure using the air 52 preheated by the air preheater AH51. A steam turbine 57 which uses the exhaust gas 54 discharged from the boiler 53 as a heat source for steam generation and drives the generator 56 using the generated steam 55; From the condenser 59 which collects and circulates the water 58 condensed in the 57, the flue gas denitrification apparatus 60 which denitrates the exhaust gas 54 discharged from the boiler 53, and the boiler 53 A dust collecting device 61 for removing the dust in the exhaust gas 54 discharged, a flue gas desulfurization absorption tower 71 for removing sulfur components in the exhaust gas 54 using the seawater 62, and a flue gas desulfurization absorption tower A water quality recovery process of the sulfur component absorbing seawater 63A including the sulfur component produced at 71 at a high concentration is performed. Is made of a chimney 66 for discharging the seawater flue gas desulfurization apparatus 64 and the exhaust gas 54, the purge gas desulfurization process (65) in a flue gas desulfurization absorber 71 to the outside.

The air 52 supplied from the outside is supplied to the air preheater 51 by the press-fit fan 67 and is preheated. Fuel (not shown) and air preheated in the air preheater 51 are supplied to the burner, and the fuel is burned in the boiler 53 to generate steam 55 for driving the steam turbine 57. . In addition, the fuel (not shown) used in this embodiment is supplied, for example from an oil tank.

The exhaust gas 54 generated by burning in the boiler 53 is fed to the flue gas denitrification apparatus 60. At this time, the exhaust gas 54 exchanges heat with the water 58 discharged from the condenser 59 and is used as a heat source for generating steam 55, and the generated steam 55 is a generator 56 of the steam turbine 57. ) Is driving. The water 58 condensed in the steam turbine 57 is returned to the boiler 53 for circulation.

Then, the exhaust gas 54 discharged from the boiler 53 and introduced to the flue gas denitrification apparatus 60 is denitrified in the flue gas denitrification apparatus 60, and after heat exchange with the air 52 in the air preheater 51. Is supplied to the dust collector 61 to remove the dust in the exhaust gas 54.

Then, the exhaust gas 54 subjected to the dust removal treatment by the dust collector 61 is supplied to the seawater flue gas desulfurization apparatus 64. As the seawater flue gas desulfurization apparatus 64, the seawater flue gas desulfurization apparatus according to the present invention is used. That is, the seawater flue gas desulfurization apparatus 64 includes the flue gas desulfurization absorption tower 71 for purifying the sulfur component in the exhaust gas 54 by contacting the absorbing sea water 62A, which is a part of the sea water 62, and the flue gas desulfurization absorption. The sulfur component absorbing seawater 63A formed integrally under the column 71 and desulfurized by contacting the sulfur component in the exhaust gas 54 with the absorbing seawater 62A in the flue gas desulfurization absorption tower 71 is absorbed. The dilution mixing tank 73 is mixed and diluted with the dilution seawater 62B fed into the main body 72, and the dilution mixing tank 73 is disposed at the lower end side of the side wall 74 of the flue gas desulfurization absorption tower 71. ) And the lid portion 75 extended along the longitudinal direction of the dilution mixing tank 73 and the rear surface side of the lid portion 75 so that the end portion is buried in the water surface in the dilution mixing tank 73. It has the gas retention part 77 provided with the 1st bank 76 to make. Further, an oxidation tank 78 is provided integrally with the dilution mixing tank 73 on the downstream side of the dilution mixing tank 73, oxidizes and decarbonates the sulfur component in the sulfur component absorption seawater 63B to obtain water quality. Do a recovery. The sulfur component absorbing seawater 63B is seawater in which the dilution seawater 62B and the sulfur component absorption seawater 62A flowing down in the flue gas desulfurization absorption tower 71 are mixed in the flue gas desulfurization absorption tower 71. In the oxidizing tank 78, an air blower 80 for supplying air 79, an air diffuser 81 for supplying air 79, and air 79 are provided with seawater ( The nozzle 82 for oxidizing air supplied to 62C) is provided.

Specifically, the exhaust gas 54 is supplied into the flue gas desulfurization absorption tower 71 by the attraction fan 83. At this time, the exhaust gas 54 is heat-exchanged with the purification gas 65 which is desulfurized and discharged from the flue gas desulfurization absorption tower 71 in the heat exchanger 84, and then is supplied into the flue gas desulfurization absorption tower 71.

In the flue gas desulfurization absorption tower 71, seawater desulfurization is performed by using a part of the seawater 62 which is contained in the exhaust gas 54 from the sea 85 as the absorbing seawater 62A. The exhaust gas 54 generated by burning the fossil fuel contains a sulfur component, which is a sulfur oxide (SO _X ), in the form of SO ₂ or the like. Exhaust gas from the flue gas desulfurization absorber 71, 54 and the water supply line 86 a to the gas-liquid contact with the sea water (62A) for absorbing, water for absorbing the SO ₂ in the exhaust gas 54 to be supplied through (62A) Is absorbed into the seawater to desulfurize. Further, the seawater 62 pumped up from the sea 85 by the pump 87 is heat-exchanged with the condenser 59, and then absorbed seawater which is a part of the seawater 62 which is a drainage of the condenser 59 ( 62A) is fed to the flue gas desulfurization absorption tower 71 by the pump 88. In addition, the purification gas 65 desulfurized in the flue gas desulfurization absorption tower 71 is discharged from the chimney 66 to the atmosphere.

63 A of sulfur component absorption seawater is collect | recovered in the dilution mixing tank 73 integrated in the lower side of the flue gas desulfurization absorption tower 71. In addition, a part of the seawater 62 is supplied to the dilution mixing tank 73 through the dilution seawater supply line 89 as the dilution seawater 62B. As a result, the sulfur component absorbing seawater 63A can be diluted in the dilution seawater 62B, and the pH of the sulfur component absorbing seawater 63B can be raised.

In addition, the lid portion in which the gas reservoir 77 extends along the long direction of the dilution mixing tank 73 so as to cover the dilution mixing tank 73 on the lower end side of the side wall 74 of the flue gas desulfurization absorption tower 71. 75 and a gas reservoir 77 provided with a first weir 76 which is dripped from the back surface side of the lid portion 75 and whose end portion is buried in the water surface in the dilution mixing tank 73. Because of this, to dissipate the bubbles (90) containing a high concentration of SO ₂ gas rolled in a bottom portion (73a) of the dilution mixing chamber (73) in the space (S11) in the gas reservoir portion 77, the area (S11 ), It is possible to prevent the SO ₂ gas from leaking into the downstream oxidation tank 77.

In addition, in this embodiment, although it demonstrated using the 1st seawater flue gas desulfurization apparatus which concerns on this embodiment mentioned above as seawater flue gas desulfurization apparatus 64, it is not limited to this, According to this embodiment mentioned above Second to fourth seawater flue gas desulfurization devices can be used.

Then, the air 79 is supplied from the oxidizing air blower 80 through the diffuser pipe 81 into the oxidizing bath 78 from the oxidizing air nozzle 82, and hydrogen sulfite ions in the sulfur component absorbing seawater 63B. While oxidizing, carbon dioxide is desorbed from bicarbonate ions. As a result, the sulfur component absorbing seawater 63B recovers the water quality to become the water-modified seawater 91.

Thereafter, the water-modified seawater 91 subjected to the water quality recovery process in the oxidizing tank 78 is discharged into the sea 85 as seawater drainage through the seawater discharge line 92.

As described above, according to the seawater desulfurization system 50 according to the present embodiment, the sulfur component absorbing seawater 63 generated by seawater desulfurization in the oxidizing tank 77 is recovered in the dilution mixing tank 73 and the dilution seawater 62B. Air bubbles containing a high concentration of SO ₂ gas generated by mixing and diluting and being rolled up by dilution of sulfur component absorbing seawater 63A in dilution seawater 62B at the bottom of the dilution mixing tank 73 ( 90 can be dissipated to the downstream open oxidizing tank 77 to prevent SO ₂ from leaking to the outside, whereby a safe and reliable seawater desulfurization system can be provided.

As described above, the seawater flue gas desulfurization apparatus according to the present invention prevents sulfur-absorbed seawater generated by seawater desulfurization from being mixed with dilution seawater so that SO ₂ entrained in seawater is not dissipated to the outside during oxidation treatment. Since it is possible to do so, it is suitable for the seawater flue gas desulfurization apparatus which adjusts to discharge | release the seawater used for seawater desulfurization to the ocean.

10-1 to 10-4: 1st seawater flue gas desulfurization apparatus to 4th seawater flue gas desulfurization apparatus
11: exhaust gas
12, 12A, 62, 62A: Seawater (absorption seawater)
12B, 62B: dilution seawater
13, 71: flue gas desulfurization absorption tower
14A, 14B: sulfur component absorption seawater
15, 72: main body
16, 73: dilution mixing tank
16a: bottom
17, 74: side wall
18, 75: lid
18a: end
19, 76: first bank
19a: end
19b: inner wall
20A to 20D, 77: gas reservoir
21, 85: sea
22, 24: pump
23, 86: seawater supply line
25: purifying gas
26: purge gas discharge passage
27, 88: dilution seawater supply line
28, 90: bubble
29, 78: oxidation tank
30: air supply
31, 79: air
32, 80: air blower for oxidation
33, 81: diffuser
34, 82: nozzle for oxidizing air
35, 91: water reforming seawater
36, 92: seawater discharge line
42: second dam
42a: end
42b: inner wall
43: third dam
43a: end
43b: outer wall
44: ventilator
50: seawater desulfurization system
51: air preheater (AH)
52, 78: air
53: boiler
54: exhaust gas
55: steam
56: generator
57: steam turbine
58: water
59: avengers
60: flue gas denitrification device
61: dust collector
63: sulfur component absorption seawater
64: seawater flue gas desulfurization apparatus
65: purifying gas
66: chimney
67: indentation fan
83: manned fan
84: heat exchanger
87, 88 pump
S1 to S2, S11: space

Claims (13)

A flue gas desulfurization absorption tower for purifying the sulfur component in the exhaust gas by contact with sea water, and
The sulfur component absorbing seawater, which is integrally installed under the flue gas desulfurization absorption tower and is formed by contacting the seawater with the sulfur component in the exhaust gas in the exhaust gas desulfurization absorption tower and desulfurized by seawater, is mixed and diluted with seawater supplied into the main body. While having a dilution mixing tank to say,
And a lid portion extended to cover the dilution mixing tank on the lower end side of the side wall of the flue gas desulfurization absorption tower, and a first weir received from the back surface side of the lid portion, and the end of which is embedded in the water surface in the dilution mixing tank. Have a gas reservoir,
A seawater flue gas desulfurization apparatus, characterized in that the length L1 from the side wall of the flue gas desulfurization absorption tower to the inner wall of the first dam satisfies any one of Equations 1 and 2 below.
About bubble diameter dp in seawater,
[Equation 1]
d _G1 <τ ₁ U _t (dp)
&Quot; (2) &quot;
Cc> C ₀ exp (-6 Kg / dpτ ₁ )
&Quot; (3) &quot;
τ ₁ = L1 / U _L
Where d _G1 is the opening height from the first bank at the outlet of the gas reservoir to the bottom of the dilution mixing tank, τ ₁ is the residence time of the seawater in the gas reservoir, and U _t (dp) is the bubble diameter dp in the seawater. Is the terminal ascending velocity of the bubble group of, Cc is the SO ₂ environmental reference concentration, C ₀ is the SO ₂ concentration at the inlet of the flue gas desulfurization absorption tower of the exhaust gas, and Kg is the SO ₂ gas at the gas-liquid interface of the bubble. It is the overall mass transfer coefficient, dp is the bubble diameter, and U _L is the outlet flow rate at the bottom of the dilution mixing bath. delete The method of claim 1,
A seawater flue gas desulfurization apparatus comprising a second dam at a bottom of the dilution mixing tank. The method of claim 3, wherein
A seawater flue gas desulfurization apparatus, characterized in that the length L2 from the side wall of the flue gas desulfurization absorption tower to the inner wall of the second weir satisfies any one of the following expressions (5) and (6).
&Quot; (5) &quot;
D <τ ₂ U _t (dp)
&Quot; (6) &quot;
Cc> C ₀ exp (-6 Kg / dpτ ₂ )
&Quot; (7) &quot;
τ ₂ = L2 / (U _L × D / d _G2 )
However, D is the liquid depth of the seawater of the dilution mixing tank, τ ₂ is the residence time of the seawater in the gas reservoir, U _t (dp) is the terminal rising rate of the bubble group of bubble diameter dp in the seawater, Cc is SO _{2 is the} environmental reference concentration, C ₀ is the concentration of SO ₂ at the inlet of the flue gas desulfurization absorption tower of the exhaust gas, Kg is the overall mass transfer coefficient of SO ₂ gas at the gas-liquid interface of bubbles, and dp is the bubble diameter. , U _L is the outlet flow rate at the bottom of the dilution mixing tank, and d _G2 is the height of the liquid level between the sea level and the second weir. The method of claim 1,
A seawater flue gas desulfurization apparatus, characterized in that a third dam is provided inside the gas reservoir. The method of claim 5, wherein
A length L3 from the outer wall of the third dam to the inner wall of the first dam satisfies any one of Equations 8 and 9 and Equation 10 below.
&Quot; (8) &quot;
d _G1 <τ ₃ U _t (dp)
&Quot; (9) &quot;
Cc> C ₀ exp (-6 Kg / dpτ ₃ )
[Equation 10]
τ ₃ = L3 / (U _L × D / MIN (d _G1 , d _G3 ))
Where d _G1 is the opening height from the first bank at the outlet of the gas reservoir to the bottom of the dilution mixing tank, τ ₃ is the residence time of the seawater in the gas reservoir, and U _t (dp) is the bubble diameter dp in the seawater. Is the terminal ascending velocity of the bubble group of, Cc is the SO ₂ environmental reference concentration, C ₀ is the SO ₂ concentration at the inlet of the flue gas desulfurization absorption tower of the exhaust gas, and Kg is the SO ₂ gas at the gas-liquid interface of the bubble. Is the overall mass transfer coefficient, dp is the bubble diameter, U _L is the outlet flow rate at the bottom of the dilution mixing tank, D is the liquid depth of the seawater in the dilution mixing tank, and d _G3 is between the end of the third weir and the bottom of the dilution mixing tank. Height, MIN (d _G1 , d _G3 ) is the minimum of d _G1 , d _G3 . The method of claim 1,
While installing a 2nd dam at the bottom of the said dilution mixing tank,
A seawater flue gas desulfurization apparatus, characterized in that a third dam is provided inside the gas reservoir. The method of claim 7, wherein
A length (L4) from the outer wall of the third dam to the inner wall of the second dam satisfies any one of Equations 11 and 12 and Equation 13 below.
[Equation 11]
D <τ ₄ U _t (dp)
&Quot; (12) &quot;
Cc> C ₀ exp (-6 Kg / dpτ ₄ )
&Quot; (13) &quot;
τ ₄ = L4 / (U _L × D / MIN (d _G1 , d _G2 , d _G3 ))
However, D is the liquid depth of the seawater of the dilution mixing tank, τ ₄ is the residence time of the seawater in the gas reservoir, U _t (dp) is the terminal rising rate of the bubble group of bubble diameter dp in the seawater, Cc is SO _{2 is the} environmental reference concentration, C ₀ is the concentration of SO ₂ at the inlet of the flue gas desulfurization absorption tower of the exhaust gas, Kg is the overall mass transfer coefficient of SO ₂ gas at the gas-liquid interface of bubbles, and dp is the bubble diameter. , U _L is the outlet flow rate of the bottom of the dilution mixing tank, d _G1 is the opening height from the first bank to the bottom of the dilution mixing tank, d _G2 is the height of the liquid level between the sea level and the second bank, and d _G3 is It is the height of the opening from 3 banks to the bottom of the dilution mixing tank, and MIN (d _G1 , d _G2 , d _G3 ) is the minimum of d _G1 , d _G2 , d _G3 . 9. The method according to any one of claims 5 to 8,
And said third dam has a vent therein for communicating the space between said gas reservoir and said seawater and said flue gas desulfurization absorption tower. The method according to any one of claims 1 and 3 to 8,
Seawater flue gas desulfurization apparatus, characterized in that the seawater is discharged from the condenser. The method according to any one of claims 1 and 3 to 8,
Installed in the downstream of the dilution mixing tank,
A seawater flue gas desulfurization apparatus comprising an oxidizing tank for oxidizing and decarbonizing the sulfur component in the seawater mixed with the sulfur component absorbing seawater in the dilution mixing tank to recover the water quality. Boiler,
A steam turbine which uses the exhaust gas discharged from the boiler as a heat source for steam generation and drives the generator using the generated steam;
A condenser for recovering and circulating water condensed in the steam turbine,
Flue gas denitrification apparatus for denitrifying exhaust gas discharged from said boiler,
A dust collector for removing dust in the exhaust gas,
The seawater flue gas desulfurization apparatus according to any one of claims 1 and 3 to 8, and
Seawater desulfurization system comprising a chimney for discharging the purge gas desulfurized in the flue gas desulfurization apparatus to the outside. A method for treating desulfurized seawater, which is characterized in that the SO ₂ gas contained in the seawater used for desulfurization is prevented from being discharged to the outside by using the seawater flue gas desulfurization apparatus according to any one of claims 1 and 3 to 8. .

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