JPH06198121A - Wet flue gas desulfurizer equipped with adsorption tower - Google Patents

Abstract

PURPOSE:To improve the utilization factor of a space, to lower the height of a spray adsorption tower and to improve the profitability by providing the spray nozzles of the front stage and back stage of those in plural stages having the spray directions parallel and opposite to that of the flow of gas respectively one after the other and also causing no interference between then. CONSTITUTION:Spray piping 4 in plural stages is installed in a wet flue gas desulfurizer and spray nozzles 7 in plural stages provided on the piping 4 are divided into those of the front stage and back stage. And upward nozzles 7 and downward nozzles 7 are arranged so that their openings may not face each other to perform both opposite spraying and parallel spraying. And spaces are left between the spray nozzles so that no interference between the opposite and parallel spraying may be caused. Therefore two-fold spray is made.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a desulfurizer,
The present invention relates to a wet flue gas desulfurization apparatus equipped with an absorption tower suitable for spraying an absorbent with space efficiency.

[0002]

2. Description of the Related Art In a limestone-gypsum method wet flue gas desulfurization system for removing sulfur oxides contained in boiler flue gas, a single tower spray is used for continuously cooling, removing dust and absorbing boiler exhaust gas in one tower. FIG. 6 shows a schematic structure of a type absorption tower having four spray stages. In FIG. 6, the gas to be treated is introduced into the spray type absorption tower 9 through the gas inlet 1, and is cooled and dust-removed by the absorption liquid sprayed from the cooling liquid spray pipe 2 installed in the lower part of the spray type absorption tower 9, After the gas flow is made uniform through the gas dispersion plate 3, it is vaporized in a state of being opposed to the fine droplets of the absorbent slurry which are sprayed in a conical shape from the absorbent spray nozzle 7 installed in the absorbent spray pipe 4. In liquid contact, absorbs sulfur oxides in the gas. After absorbing the sulfur oxides in the gas, the absorbing liquid slurry stored at the bottom of the spray type absorption tower 9 is carried to the absorbing liquid spray pipe 4 by the circulation pump 8 and is circulated for use. Further, after the scattered mist from the absorption tower 9 is removed by the mist eliminator 5 arranged at the gas outlet 6, the processing gas is discharged into the atmosphere.

Further, a stirrer 12 is provided at the bottom of the spray type absorption tower 9 to prevent the solid content of the stored absorbent slurry, and an agitator 11 for oxidation is provided to surround the stirrer 11. Oxidizing air is injected from here to oxidize the calcium sulfite produced by the sulfur oxide absorption reaction to produce gypsum. The limestone slurry, which is a sulfur oxide absorbent, is supplied to the spray type absorption tower 9 through the limestone slurry supply pipe 13.
Part of the absorption liquid slurry is discharged to the outside of the spray absorption tower 9 through the absorption liquid slurry extraction pipe 14, and the gypsum by-produced by the absorption reaction is recovered.

In the spray type absorption tower 9, as shown in FIG. 7, in order to remove sulfur oxides, the absorption liquid slurry is sprayed downward from the absorption liquid spray nozzle 7 in a conical shape, and the absorption liquid slurry is applied to the untreated gas. Contact countercurrently. At this time, there is a basin A part in which the spraying is not performed, which is shown by hatching in FIG. The number of stages of the absorption liquid spray pipe 4 varies depending on the concentration of sulfur oxides in the gas to be treated and the required absorption performance, but is usually 3 to.
There are 6 stages, and sometimes 6 stages or more, and the stages of the absorbing liquid spray nozzle 7 are equidistant from each other as shown in FIG.
Is set in.

FIG. 8 shows the arrangement of the absorbent spray nozzle 7 in each stage of the absorbent spray pipe 4. The liquid droplets sprayed from the absorbing liquid spray nozzle 7 are shown in FIG.
As shown in (b), both the upper and lower stages are aligned and arranged in a square corner portion, and the upper spray nozzle 7a and the lower spray nozzle 7b are combined with each other. For example, when the number of spray stages is 4, the gas flow direction is 8 (b),
8A, 8B and 8A are combined in the order shown and arranged as shown in FIG. 8C. The arrangement of the upper stage spray nozzle 7a and the lower stage spray nozzle 7b from the upper part of the spray type absorption tower 9 is as shown in FIG. 8C, and the upper stage spray nozzle 7a and the lower stage spray nozzle 7b are squares formed by the spray nozzles 7 of other stages. It is arranged to be located in the center of the.

[0006]

The above-mentioned spray tower type gas-liquid contactor of the prior art requires a certain space for diffusion of the spray droplets, so that when the number of stages of the spray pipe 4 is large, the spray type absorption device is used. There was a problem that the tower height of the tower 9 becomes high. The object of the present invention is to improve the space utilization rate by reviewing the arrangement structure of the spray nozzle, which is a gas-liquid contact absorption device of an absorption liquid type absorption tower, and lower the height of the spray type absorption tower,
(EN) It is intended to provide a wet flue gas desulfurization device with improved economy.

[0007]

The above objects of the present invention can be achieved by the following constitutions. That is, the absorbing liquid is sprayed from the spray nozzles arranged in multiple stages in the gas flow direction,
In a wet flue gas desulfurization apparatus having an absorption tower for removing sulfur oxides in exhaust gas, a plurality of spray nozzles are opposed sprays in which the spray directions of the spray nozzles of the upstream and downstream stages are alternately arranged with respect to the gas flow, From a combination of parallel spraying, and a wet flue gas desulfurization device equipped with an absorption tower with spray nozzle stages spaced so that opposing sprays do not interfere with each other, or spray nozzles arranged in multiple stages in the gas flow direction In a wet flue gas desulfurization device equipped with an absorption tower that sprays the absorbing liquid and removes sulfur oxides in the exhaust gas, each of the spray nozzles in multiple stages is provided with an upward nozzle and a downward nozzle, and the upstream and downstream stages are provided. In the wet flue gas desulfurization equipment equipped with an absorption tower in which spray nozzles are arranged so that the upward spraying direction and the downward spraying direction of each spray nozzle do not interfere with each other. That.

[0008]

In the present invention, the space is provided by spraying from the upward spray nozzle so as to be a parallel flow to the gas flow in the region A where the downward spray nozzle shown in FIG. It is used effectively. Figure 7 above
Figure 2 shows an image of spraying the basin A of
Shown in. In the figure, the ∘ mark indicates the nozzle position of the downward spray, and the × mark indicates the nozzle position of the upward spray. In FIG. 2, the downward spray having the conventional structure is subjected to the upward spray indicated by the diagonal lines from a level where they do not interfere with each other, so that a double amount of the conventional spray can be performed in the same space. It is possible to make effective use of the space of part A. Further, as shown in FIG. 2, the upward spray and the downward spray do not interfere with each other in the traces of the sprayed droplets, so that the absorption performance does not deteriorate.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to FIGS. FIG. 1 shows a schematic structure of a spray type absorption tower of the present embodiment, and the configuration other than the arrangement of the absorbing liquid spray nozzle 7 is the same as the conventional spray type absorption tower 9 shown in FIG. 1 in FIG.
An image diagram of the absorbing liquid spray in the configuration of the spray nozzle 7 is shown, and details thereof are as described in the above-mentioned action column.

That is, FIG. 1 corresponds to FIG. 8 described in the prior art.
(B) The downward nozzle 7b is rotated by 180 ° as an upward nozzle and is arranged between the gaps that spread in a conical shape of the downward spray as shown in FIG. 2, and the number of spray stages is four. While the upward spray nozzle 7 in the figure, the absorbent spray pipe 4
And each nozzle 7 of the absorbent spray pipe 4 of the downward nozzle 7
Of the absorption liquid spray pipe 4 where the openings of the two do not face each other L ₁
Fig. 6 shows a space L between the absorbent spray pipes 4 of the prior art.
It is a small one. In FIG. 1, the interval L ₁ between the absorbent spray pipes 4 in which the openings of the nozzles 7 do not face each other and the interval L ₂ between the absorbent spray lines 4 of the upward and downward nozzles 7 in which the nozzle openings face each other are: As shown in FIG. 2, since the upward spray is performed in the space in which the downward spray is wide, L = L ₁ + L ₂ with respect to the interval L between the absorbent spray pipes 4 in FIG. 6.

When the number of stages of the absorbing liquid spray pipe 4 is 4, in the case of the conventional spray type absorption tower 9 shown in FIG. 6, the interval between the spray stages is 4 L from the gas dispersion plate 3. On the other hand, in the case of the present embodiment, the interval 2L is sufficient as shown in FIG. In this case, the head of the absorbent circulating pump 8 is also lowered, which makes the running cost economical. For example, when the circulation pump head in the case of FIG. 6 is 31 m, even if the same spray device is used in the case of FIG.
It will be 8 m, and the power can be reduced by about 10% {(31-28)
/31≈0.1}.

Further, as shown in FIG. 3, there is shown an example in which an absorption liquid spray nozzle 7 capable of spraying the absorption liquid in the vertical direction is provided at the stage of each absorption liquid spray pipe 4. In the case of FIG. 3, the absorption liquid spray pipe 4 needs to have a capacity twice as large as that shown in FIG. 1, but the spray from the upward nozzle and the downward nozzle are the same as those shown in FIG. The nozzles are arranged so as to be sprayed between the conical spreads of the spray by the upward nozzles or the downward nozzles of the adjacent stage.
Since the number of spray stages can be achieved by using two absorbing solution spray pipes 4, the total spacing of the spray stages is as shown in FIG.
As shown in, the interval of 2 L is sufficient (4 L is required in the case of FIG. 6). FIG. 4 shows a mounting state diagram of the absorbent spray nozzle 7 in FIG. 3, and FIG. 5 shows an image of the gas to be processed passing in the case shown in FIG.

As described above, according to the present embodiment, the absorption liquid is sprayed from the bottom to the top by effectively utilizing the gap between the absorption liquid sprays generated by the conventional arrangement of the spray nozzle 7 facing only downward. Thus, it is possible to reduce the absorption liquid spray area of the spray type absorption tower 9 and obtain the same performance as in the prior art. In addition, since the spray area is about half that of the conventional one, the height of the absorption tower 9 can be reduced, and at the same time, the spray hydrostatic head of the absorbing liquid slurry can be reduced to reduce the power consumption of the circulation pump 8 and other economic effects. Obtainable. This effect is more remarkable as the number of spray stages increases.

Although the above embodiment describes the absorption tower of the limestone-gypsum method wet flue gas desulfurization apparatus using limestone slurry as an absorbent, the present invention can be applied to all kinds of spray type gas-liquid contactors. However, there is no limitation on the type of gas to be passed and the spray nozzle type and the number of spray stages.

[0015]

EFFECTS OF THE INVENTION According to the present invention, the desulfurization performance can be made equal to the conventional one by effectively utilizing the gaps between the absorbent liquid sprays and reducing the spray area of the spray type absorption tower. . In addition, since the spray area of the absorbing liquid is about half that of the conventional type, the height of the absorption tower can be lowered, and the economical effect such as the power consumption of the circulation pump can be reduced by lowering the spray hydrostatic head of the absorbing liquid slurry. You can

[Brief description of drawings]

FIG. 1 shows a schematic structural diagram of a spray type absorption tower of an embodiment of the present invention.

FIG. 2 is an image diagram showing a relationship between an upward spray and a downward spray of a spray nozzle used in the absorption tower of FIG.

FIG. 3 shows a schematic structural diagram of a spray type absorption tower of an embodiment of the present invention.

FIG. 4 is a view showing a state where a spray nozzle used in the absorption tower of FIG. 3 is attached.

5 is a diagram showing an image in which a gas to be processed passes around a spray nozzle of the absorption tower shown in FIG.

FIG. 6 is a view showing a schematic structure of a conventional spray type absorption tower.

FIG. 7 is a view showing a conventional spray nozzle installation and spray situation.

FIG. 8 is a view showing a planar arrangement of conventional spray nozzles.

[Explanation of symbols]

1 ... Gas inlet, 2 ... Coolant spray pipe, 3 ... Gas dispersion plate, 4 ... Absorber spray pipe, 5 ... Mist eliminator,
6 ... Gas outlet, 7 ... Absorption liquid spray nozzle, 8 ... Circulation pump, 9 ... Spray type absorption tower

Claims (2)

[Claims] 1. A wet flue gas desulfurization apparatus equipped with an absorption tower for spraying an absorbing solution from spray nozzles arranged in multiple stages in the gas flow direction to remove sulfur oxides in exhaust gas, The spray directions of the spray nozzles in the upstream and downstream stages are a combination of opposing sprays and parallel sprays that are alternately arranged with respect to the gas flow, and the spacing between the spray nozzles is set so that the opposing sprays and parallel sprays do not interfere with each other. A wet flue gas desulfurization device equipped with a characteristic absorption tower. 2. A wet flue gas desulfurization apparatus equipped with an absorption tower for spraying an absorption liquid from spray nozzles arranged in multiple stages in the gas flow direction to remove sulfur oxides in exhaust gas, each of the plurality of stages of spray nozzles. In the absorption tower, an upward nozzle and a downward nozzle are provided, and a spray nozzle is arranged so that the spray directions of the upward nozzle and the downward nozzle of each of the spray nozzles in the upstream and downstream stages do not interfere with each other. Wet flue gas desulfurization equipment equipped.