JPS63107731A - Exhaust gas purifying apparatus - Google Patents

Abstract

PURPOSE:To enhance purifying capacity and dust removing efficiency, by parallelly providing two or more reticulated mats directly under the chemical agent scattering nozzle provided in the main body of an absorbing tower so as to form an angle with respect to the exhaust gas stream rising in the main body of the absorbing tower. CONSTITUTION:Exhaust gas containing a large amount of SOx and soot is supplied to a cooling part held to 80-90 deg.C at 150-250 deg.C and introduced into an absorbing tower main body 1 while cooled and increased in humidity. The exhaust gas rises while receiving the absorbing liquid (alkali liquid) scattered from an absorbing liquid spray 2 and passes through the gaps of reticulated mats 3 sufficiently wetted with the absorbing liquid on the way of rising to be contacted with the wires of the mats 3, and the desulfurization of the exhaust gas and the removal of soot are performed. By limiting the mutual intervals between the adjacent reticulated mats 3, a superposed part is necessarily generated between the adjacent mats in a vertical direction in the inclined posture of the mats 3 and almost all of the exhaust gas passes through the mats to rise.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an exhaust gas purification device that absorbs and removes harmful components, soot, and the like contained in combustion gas and exhaust gas.

[Conventional technology]

Sulfur oxides,
Contains large amounts of harmful substances such as soot and dust. In order to remove these harmful components, an absorption tower with a built-in wet desulfurization device is installed in the exhaust pipe of a boiler or the like, and the exhaust gas is released into the atmosphere through the absorption tower.

Absorption towers for flue gas desulfurization equipment differ greatly from absorption towers used in the general chemical industry in their collection function, which is based on the fact that a large amount of soot and dust is contained in the exhaust gas from boilers and the like. In particular, in boilers, in order to remove soot and dust attached around the wood pipes, a high-pressure spray is periodically applied to remove it (suit blow), so a large amount of soot and dust is thrown into the absorption tower at once. This tends to cause clogging of the mesh and packed bed installed inside the tower.

[Problem that the invention seeks to solve]

In fact, clogging is a major problem in packed bed spray absorption towers, which are said to be highly efficient. On the other hand, with perforated plate Moretana type, shock tube type, and floating ball contact type absorption towers, the problem of clogging is relatively eliminated and they exhibit great performance under the design gas volume, but when the exhaust gas volume fluctuates significantly, the problem of clogging is relatively eliminated. It has the disadvantage that it cannot follow the flow and the purification ability is greatly reduced.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems and to provide an exhaust gas purification device that has excellent purification ability and dust removal efficiency regardless of the amount of exhaust gas.

[Means for solving problems]

The present invention is equipped with an absorption nozzle for dispersing chemicals into the absorption tower main body which has an exhaust gas inlet at the bottom, and is installed directly below the absorption nozzle at an angle with respect to the gas flow of the exhaust gas rising inside the absorption tower main body. This exhaust gas purification device is characterized in that two or more reticulated mats are arranged in parallel, and in particular, the installation angle of the reticulated mats can be changed from side to side with respect to a vertical axis.

〔Example〕

Embodiments of the present invention will be described below with reference to the drawings.

In FIG. 4, absorption liquid sprays 2, 2. Set up a column of...
A row of reticulated mats 3 is arranged between the upper and lower rows of sprays 2. The absorption tower main body 1 has an exhaust gas inlet 4 in its lower part, and in an inlet pipe 5 communicating with the inlet 4, absorption liquid sprays 6 forming exhaust gas cooling sections are installed above and below. A liquid tank 7 for absorbing liquid is formed at the bottom of the absorption tower main body 1 over a certain height range, and the inside of the liquid tank 7 and the absorption liquid sprays 2, 2 . ... and the spray 6 of the cooling section are connected by pumps 8 and 9, respectively. The smoke pipe 11 of the boiler 10 is connected to the feed pipe 5.

Fig. 2 shows the structure of the reticulated mat 3 which is the main part of the present invention.The reticulated mat 3 used in this embodiment is made by looping ultra-fine wires between two shafts 12 and 13 arranged above and below at a constant interval. The knitted wire mesh is passed one to several times to form a reticulated mat 3 of a required thickness. This reticulated mat 3 has irregularities of looped wires formed on its surface.
The porosity within the mat 3 is 99.5% or more. However, the reticulated mat 3 used in the present invention is not necessarily limited to the above-mentioned structure, and may be any structure as long as it retains its shape and supports the upper and lower sides of the mat with high porosity.

Two or more reticulated mats 3, 3. shown in FIG. ... as the first
Arrange them in parallel at regular intervals as shown in the figure.

An upper shaft 12 supporting the reticulated mat 3 is rotatably suspended horizontally on the inner wall of the absorption tower main body 1, and a lower shaft 13 is connected to a common control rod 14. By pulling one end of the control rod 14 out of the absorption tower main body 1 and reciprocating it automatically or manually, each reticulated mat 3 can be tilted left and right about the upper shaft 12. For example, set the range of deflection to 45 to 60 to the left and right.
The position of each reticulated mat 3 is set to an appropriate angular position including vertical position.

In the embodiment, by starting the pumps 8, 9, the sprays 2, 2, . ..., 6゜6
, . . . spouts an absorption liquid (alkaline liquid) and circulates it, and introduces exhaust gas from the boiler 10.

Exhaust gas generally has a temperature of 150℃ to 250℃ and contains a large amount of SOx.
It contains soot and dust, and has a moisture content of about 8%. The high-temperature exhaust gas is first cooled and humidified to 80°C to 90°C in the cooling section, and then enters the absorption tower main body 1. The exhaust gas introduced into the absorption tower main body 1 is sprayed into sprays 2, 2. It rises while being sprayed with absorption liquid from ..., and on the way up, it passes through the gaps in the reticulated mat 3 that are sufficiently wetted with the absorption liquid, and touches the filaments of the mat 3, which desulfurizes the exhaust gas and removes soot and smoke. It will be done. The exhaust gas that has passed through the reticulated mat 3 contains a large amount of mist due to increased humidity. This mist is removed by a mist separator 15 installed at the upper stage within the absorption tower main body 1, and the exhaust gas is released into the atmosphere.

The mist separator 15 can be made of the same material as the reticulated mat 3. However, although it depends on the purpose of the separator, it is generally set to be thinner than the thickness of the reticulated mat. In the present invention, the soot contained in the exhaust gas adheres and accumulates on the reticulated mat 3, causing so-called clogging, as in the prior art.

However, in the present invention, clogging is eliminated by controlling the angular posture of the reticulated mat depending on the degree of contamination of the mat.

In FIG. 3(a), first, each net-like mat 3 is tilted all at once in either the left or right direction, for example, tilted upward to the right and set. Due to the regulation of the spacing between adjacent reticulated mats 3, when the mats are in an inclined position, there is always a vertical overlap between the adjacent mats, and most of the exhaust gas passes through the mats and rises.

The soot contained in the exhaust gas mainly adheres and accumulates on the lower surface side of the mat 3. As soot and smoke adhere to mat 3,
By operating the control rod 14, each mat 3 is moved as shown in FIG. 3(b).
From the vertical position shown in FIG. 3(c), the robot is further reversed and changed to a tilted position upward to the left. Due to this attitude change, the surface to which soot and smoke adheres in the attitude shown in FIG. It receives a shower of absorbent ejected from ..., and the soot is washed away by the backwashing action, restoring its adsorption capacity. By repeating the above operations, the desulfurization and dust removal effects can be maintained for a long period of time.

In the present invention, the contact area of exhaust gas can be adjusted by controlling the posture of each reticulated mat, and even if the reticulated mat itself becomes clogged, the exhaust gas can flow between the mats, so that the exhaust gas can flow easily. The resistance will not be excessive.

〔Effect of the invention〕

The effects of the present invention are as follows.

1) Prevents mat clogging.

Since the posture of the mat can be freely controlled even while driving and the mat can be easily backwashed without changing the spray position, there is no need to worry about clogging even if a large amount of soot and dust is concentrated and blown away.

2) Dust removal efficiency and desulfurization efficiency can be easily changed during operation.

Dust removal efficiency is improved because the contact rate between exhaust gas and alkaline solution changes by changing the posture between the mats.

Desulfurization efficiency can also be controlled freely. In particular, it is possible to follow and control fluctuations in the amount of exhaust gas.

3) The removal efficiency of soot and dust is high and always constant.

Because a clean wire mesh layer is always maintained,
Dust removal efficiency is always consistently high.

4) SOx removal efficiency is high and always constant.

The mat always maintains a clean wire mesh layer with no blockage, and the exhaust gas flows uniformly within the mat, resulting in high and constant desulfurization efficiency.

In particular, even if magnesium hydroxide or lime is used as an alkaline agent, crystals will not form and blockage will not occur.

5) Pressure loss is small and always constant.

If a wire mesh structure with a porosity of 99.5% or more is used for the mat, the pressure loss will be extremely small.In particular, the mat will be backwashed depending on the dirt, and the wire mesh structure will not be used.

6) Able to drive economically.

Even if there are large fluctuations in the amount of exhaust gas, the posture of the mat can be changed according to the amount of gas to maintain a constant efficiency.
By making the blower and pump follow the amount of exhaust gas, the most economical operation is possible. Further, wasteful consumption of alkaline agents is also eliminated.

[Brief explanation of the drawing]

Fig. 1 is a front view showing an installation example of the reticulated mat used in the device of the present invention, Fig. 2 is a perspective view showing the structure of the reticulated mat, and Fig. 3 is a perspective view showing the structure of the reticulated mat.
Figures (a) to (c) are explanatory diagrams showing how to change the posture of the reticulated mat, and Figure 4 is a schematic diagram of an absorption tower equipped with the device of the present invention. 1... Absorption tower/main body 2... Absorption liquid spray 3... Reticulated mat 12... Upper shaft 13.
・・Lower shaft 14・・Control rod patent applicant Shigeru Okayama 2 Meiku No. night spray (b) Fig. 3 fifi' (Fig. 3

Claims (2)

[Claims] (1) An absorption nozzle for dispersing chemicals is provided in the absorption tower body having an exhaust gas inlet at the bottom, and a gas flow of exhaust gas rising inside the absorption tower body is provided directly below the absorption nozzle.
An exhaust gas purification device characterized by two or more mesh mats arranged in parallel at an angle. (2) The exhaust gas purification device according to claim (1), wherein the installation angle of the reticulated mat can be changed to the left or right with respect to the vertical axis.