KR200279835Y1 - Absorber Mounted with Apparatus for Uniform Gas Velocity Profile - Google Patents

Abstract

The present invention relates to an absorption apparatus of a wet flue gas desulfurization facility for efficiently removing sulfur oxides in flue gas discharged from a thermal power plant, and removes the injection nozzle (5) and the unreacted calcium carbonate component droplets for injecting the absorbing liquid. In the absorption apparatus of the wet flue gas desulfurization apparatus which consists of the absorption tower 30 in which the moisture separator 4 for this purpose is provided in order from the bottom, and the outlet duct 3 bent with respect to the said absorption tower 30, In the inner corner 40 where the absorption tower 30 and the outlet duct 3 meet, the porous plate 2 for controlling the flow of exhaust gas is installed,

Prevents the performance degradation of the mist eliminator due to the flow deflection at the upper part of the absorption tower and the flow separation phenomenon at the lower part of the outlet duct and prevents unreacted calcium carbonate liquid droplets from the absorption tower outlet duct. By eliminating the phenomenon, it is possible to prevent the performance deterioration of major equipment such as the outlet duct and the gas reheater installed at the rear stage.

Description

Absorber Mounted with Apparatus for Uniform Gas Velocity Profile

The present invention relates to an absorber having a flow homogenizer, and in particular, gas-liquid absorption in an absorber of a wet flue gas desulfurization system installed to efficiently remove sulfur oxides contained in flue gas of a conventional thermal power plant. The present invention relates to an absorption apparatus including a device for uniformizing the flow of flue gas discharged after the reaction.

Due to the increased use of fossil fuels due to increased industrial activities, sulfur oxides (particularly SO ₂ ) among the pollutants emitted from thermal power plants have a serious impact on the global environment such as air pollution and acid rain. To cope with this, in recent years, emission regulations have been strictly tightened around the world, and prevention techniques have been developed to meet emission standards.

Techniques for reducing sulfur oxides include raw material desulfurization techniques for reducing sulfur components contained in raw materials and flue gas desulfurization techniques for reducing sulfur components in discharged exhaust gas. The flue gas desulfurization technology is classified into a wet method, a dry method, and a semi-dry method according to the state of the absorbent reacting with the exhaust gas, but the wet method which is excellent overall in system stability, technology applicability, and economic efficiency is mainstream. 1, the overall schematic of the wet flue gas desulfurization apparatus is shown.

As shown in the drawing, the wet flue gas desulfurization apparatus has a water absorbing device (1) that absorbs sulfur oxides from flue gas components from a boiler (6) of a power generation facility, and increases the temperature of the flue gas discharged to corrode materials and white smoke. The gypsum by concentrating and dehydrating the gas reheater (9), which prevents and installs the lime slurry, and the limestone handling device (10) (12) (13) for supplying the lime slurry to the absorber (1). Gypsum handling apparatus 11, 14, and a wastewater treatment apparatus (not shown) for treating and discharging wastewater generated in the system. At this time, after the exhaust gas discharged from the boiler 6 flows into the main body of the absorption tower 30 of the absorber 1 by the inlet duct, it contacts and reacts with the absorbent sprayed through the injection nozzle 5. Is discharged. In addition, the absorbent absorbing sulfur oxides is oxidized in an oxidizing tank (not shown) to produce gypsum.

On the other hand, as the absorbent used in the wet method, calcium carbonate, which is inexpensive, has excellent reactivity with sulfur oxides and can utilize by-products, is most adopted for flue gas desulfurization facilities for thermal power generation, and gas-liquid contact inside the absorption tower. The spray method is the mainstream.

Development of flue gas desulfurization facilities began in the early 1970s, and since then, many improvements have been made in terms of reliability and operation methods, and simplification of processes and equipment has been made by identifying chemical reactions and increasing reaction rates in flue gas desulfurization processes. . In addition, through the accumulated operating experience, the simplification of the absorber, and the stabilization of the system, there have been attempts to improve performance, reduce installation costs and operation costs, and increase reliability.

In general, in a wet desulfurization system in which an absorption liquid containing calcium carbonate is sprayed into an absorption tower to remove sulfur oxides in contact with the flue gas discharged from a combustion device, to improve reaction efficiency and reduce power costs, The gas velocity profile should be uniform. For this purpose, a configuration has been developed, such as designing the shape of the absorber in consideration of the shape of the inlet duct portion or installing a guide vane, but the results were not satisfactory.

On the other hand, the upper part of the absorption tower 30 is usually provided with a moisture separator 4 to remove the droplets of the unreacted calcium carbonate component. In order to remove the unreacted calcium carbonate component droplets in the moisture separator 4, the flue gas flow must be not only uniform but also operated at an optimum flow rate. For this purpose, at the top of the absorption tower, not only its shape but also a sufficient safety factor must be taken into account. If the shape of the upper end of the absorption tower and the space margin are not secured, unreacted calcium carbonate component droplets are discharged together in the flue gas from the outlet duct of the absorber due to the uneven flow rate, thereby corroding the gas reheater installed at the outlet duct and the rear end. In addition, there was a problem that the performance of the major equipment, such as gas reheater by creating a scale. Hereinafter, the problem of the conventional apparatus will be described in more detail with reference to FIG. 2.

As shown in the figure, the conventional absorption tower 30 has its uppermost part connected horizontally with the outlet duct 3 and the upper end of the outlet duct 3 is largely bent with respect to the absorption tower 30. The exhaust gas passing through the absorption tower 30 in the wet flue gas desulfurization facility is subjected to a chemical reaction with the slurry injected through the injection nozzle 5 over the entire cross section of the absorption tower. It contains moisture of minutes, which is removed in the moisture separator (4). The droplet removal performance is most affected by the exhaust gas flow rate through the moisture separator 4, the proper flow rate is approximately 5-6m / s, the removal performance is greatly reduced above. However, if the upper end of the outlet duct 3 is sharply bent with respect to the absorption tower 30, the exhaust gas is discharged from the upper end of the absorption tower 30 in which the moisture separator 4 is located in an excessive amount of droplets. Cooling and condensing through the outlet duct 3 and the gas heater 9 causes scale and corrosion.

The present invention has been made to solve the above problems, the object of the invention is to specify the structural shape of the absorber in the wet flue gas desulfurization facility, to stabilize the flow of the top of the absorption tower and the outlet duct connected thereto, the absorption device This is to prevent the formation of scale or corrosion in the outlet duct and gas reheater.

1 is a schematic diagram of a wet flue gas desulfurization system having an absorption device according to the present invention.

2 is a cross-sectional view showing the structure of a conventional absorber.

3 is a cross-sectional view showing the configuration of an absorber according to the present invention.

4 is a flow rate distribution diagram when the porous plate of FIG. 3 is installed at 45 degrees.

FIG. 5 is a flow rate distribution diagram when the porous plate of FIG. 3 is installed horizontally. FIG.

(Explanation of main reference numeral)

1: absorber

2: perforated plate

3: exit duct

4: moisture separator

5: spray nozzle

6: boiler

9: gas reheater

10: limestone infusion pump

11: Gypsum Slurry Discharge Pump

12: Limestone Reservoir

13: limestone slurry tank

14: dewatering equipment

15: chimney 30: absorption tower 40: corner 60: upper end of the exit duct

In order to achieve the above object, the present invention is a device for removing sulfur oxide contained in the flue gas discharged from a combustion apparatus such as a thermal power plant by spraying calcium carbonate absorbent liquid, the injection nozzle for injecting the absorbent liquid and In the absorption apparatus of the wet flue gas desulfurization apparatus comprising an absorption tower in which a moisture separator for removing unreacted calcium carbonate component droplets is sequentially installed from below, and an outlet duct bent with respect to the absorption tower, It is characterized in that the perforated plate for controlling the exhaust gas flow is installed in the inner corner where the outlet duct meets.

Here, the porous plate is preferably installed in the horizontal direction.

In addition, the upper end of the outlet duct is preferably bent at an obtuse angle with respect to the absorption tower.

Hereinafter, an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

3 is a longitudinal cross-sectional view of the absorber 1 according to the present invention, and the upper portion of the outlet duct 3 is formed at an obtuse angle with respect to the absorption tower 30 in the vertical direction, so that the smooth outlet duct 3 is formed. It was to have a shape. In addition, the porous plate 2 is installed horizontally in the inward direction of the absorption tower 30 at the inner corner 40 where the absorption tower 30 and the outlet duct 3 meet to prevent the flow bias of the exhaust gas. It was made.

4 shows a flow rate distribution diagram when the porous plate 2 provided at the inner corner 40 of the absorption tower 30 and the outlet duct 3 is inclined upward by 45 degrees with respect to the horizontal plane. Since the porous plate 2 acts as a resistance to the flow, the flow distribution at the upper end of the absorption tower 30 shows an even flow unlike the conventional one, but since the porous plate 2 is inclined, the absorption tower ( The flow path from the 30 to the outlet duct 3 is narrowed, and not only excessive pressure loss occurs, but also severe flow separation phenomenon occurs at the bottom of the outlet duct 3. In addition, the flow distribution of the exhaust gas flowing into the reheater 9 connected to the absorption tower 30 may also be affected, and thus, it may not be very efficient compared to the flow improvement effect in the absorption tower.

FIG. 5 shows a flow rate distribution diagram when the porous plate 3 is installed horizontally inward at the corner portion 40 where the absorption tower 30 and the outlet duct 3 meet. By providing the perforated plate 2 horizontally, the flow path space from the absorption tower 30 to the outlet duct 3 is sufficiently secured so that the pressure loss is not large and the flow separation phenomenon occurring at the lower end of the outlet duct 3 is weakened. To remove the recycle zone.

If comprised in this way, the flow velocity of the outlet duct 3 part can be maintained at 5-6 m / s uniformly with the flow velocity in the absorption tower 30.

According to the present invention of the configuration as described above has the following advantages.

First, it is possible to equalize the flow flow by installing the porous plate horizontally at the point where the flow bias of the upper end of the absorption tower occurs.

Second, the stabilization of the flow of the top of the absorption tower and the outlet duct connected thereto can be prevented from generating scale and corrosion of the outlet duct and gas reheater of the absorption tower.

Claims (3)

A device for removing sulfur oxides contained in flue gas discharged from a combustion apparatus such as a thermal power plant by spraying calcium carbonate absorbent liquid, to remove the spray nozzle 5 for spraying the absorbent liquid and unreacted calcium carbonate component droplets. Absorption device of the wet flue gas desulfurization device configured to include an absorption tower 30 in the up and down direction, in which the moisture separator 4 is disposed in order from below, and an outlet duct 3 bent with respect to the absorption tower 30 ( In 1), Absorption device is characterized in that the porous plate (2) for controlling the flow of exhaust gas is installed in the inner corner portion (40) where the absorption tower 30 and the outlet duct (3) meet. The method of claim 1, Absorption device, characterized in that the porous plate (2) is installed in the inner corner portion (40) where the absorption tower 30 and the outlet duct (3) meet. The method according to claim 1 or 2, Absorber, characterized in that the upper end portion (60) of the outlet duct (3) is bent at an obtuse angle with respect to the absorption tower (30).