JPH0437617Y2 - - Google Patents

Description

[Detailed description of the invention] "Industrial application field" This invention removes dust (solid or liquid fine particles) contained in off-gas etc. generated during the vitrification treatment of high-level waste liquid. This technology relates to scrubbers for scrubbers, and in particular, when a gas mass is generated due to the ejection of off-gas, the dust is diffused horizontally in the middle of the dust adsorption part, and the dust is uniformly adsorbed by the dust adsorption part. It is related to.

"Conventional technology and its problems" In the process of vitrification of high-level waste liquid, the high-level waste liquid is sent into a glass melting furnace, and radioactive substances are mixed into the molten glass and solidified. A scrubber is connected to the glass melting furnace to separate and remove glass powder, radioactive substances, NOx, etc. contained in the off-gas, and dust is removed by passing through the scrubber. The off-gas is further sent to off-gas treatment devices such as an absorption tower, a ruthenium absorption tower, and a HEPA filter tower for treatment.

An example of the structure of a conventional scrubber will be explained based on FIG. 3. It includes a container 2 for storing cleaning liquid 1, a gas inflow pipe 3 inserted through the upper part of this container 2, and this gas inflow pipe. a filler casing 4 that is fitted onto the outer surface of the filler casing 3 and disposed within the cleaning liquid 1;
A dust adsorption section 5 housed in the filler casing 4 and filled with fine ceramic particles for absorbing dust in the gas, a cooling device 6 for cooling the cleaning liquid 1, and a dust adsorption section 5 for absorbing dust in the gas. This structure includes a gas outlet pipe 7 for sending the gas from which dust has been removed in the adsorption section 5 to the next processing step described above.

In a scrubber having such a structure, in order to maintain the required functions, it is desirable to feed the off-gas little by little into the cleaning liquid 1 from the gas inflow pipe 3 so that it comes into uniform contact with the dust adsorption section 5. .

However, in the scrubber shown in FIG. 3, when the amount of off-gas sent into the gas inflow pipe 3 suddenly increases, when the off-gas blows out from the lower end of the gas inflow pipe 3, it becomes a large gas mass X, and this gas mass As X is shifted from the center, large bubbles Y are formed only in a part of the dust adsorption section 5, as shown in FIG.
produces a rising slag flow. When a slag flow occurs, the dust collection efficiency in the dust adsorption section 5 is reduced, and mist is generated due to ripples on the liquid surface.
It is conceivable that the amount of mist scattered to the gas outlet pipe 7 will increase, and a complicated process will be required in the scrubber post-processing process.

The present invention solves the problems of the conventional technology, and when a gas mass is generated in the off-gas sent to the dust adsorption part, it diffuses it horizontally in the middle of the dust adsorption part. The purpose of this is to make the gas flow rate of the dust adsorption part uniform.

"Means for solving the problem" In the scrubber of the present invention, a gas inflow pipe for discharging off-gas downward is provided in a container for storing cleaning liquid, and the gas is discharged into the cleaning liquid around the gas inflow pipe. A dust adsorption part is provided that adsorbs dust by contacting with an upward flow of off-gas, and the dust adsorption part is divided into a plurality of upper and lower parts, and a plenum part filled with a cleaning liquid is provided between the divided parts. With this configuration, the gas mass of off-gas rising through the dust adsorption section becomes in a pressure released state due to the flow path resistance being reduced in the plenum section.
In addition, based on the fact that the flow path resistance increases in the next dust adsorption section, by dispersing it horizontally in the plenum section where the flow path resistance is low, the off-gas is sent to the dust adsorption section in a uniform state. This prevents pulsating flow when a gas mass is generated, suppresses ripples on the liquid surface, prevents dust components from turning into mist, and improves the dust adsorption effect.

"Embodiment" Hereinafter, one embodiment of the scrubber of the present invention will be described based on FIGS. 1 and 2. Note that parts common to the conventional example are given the same reference numerals to simplify the explanation.

In this embodiment, the dust adsorption unit 5 provided in the container 2 that stores the cleaning liquid 1 is divided into a plurality of upper and lower parts and arranged with an interval G between the divided parts. In other words, the portion at the interval G is the plenum portion 8 for filling the cleaning liquid 1.

Further, as shown in FIGS. 1 and 2, the dust adsorption section 5 has an adsorption layer formed by filling a ring-shaped metal mesh 9 with a filler 10 made of fine ceramic particles or the like as described above. As well as being formed,
When loaded between the gas inflow pipe 3 and the filler casing 4, the ring-shaped metal mesh 9 is vertically spaced apart to form a plenum portion 8.

In the figure, reference numeral 11 indicates the cooling water inlet of the cooling device 6, reference numeral 12 indicates the cooling water outlet of the cooling device 6, and reference numeral 13 indicates the gas inflow pipe 3 and the dust adsorption section 5.
A cleaning liquid discharging device for washing off dust adhering to the lower part of the drain section, and reference numeral 14 indicates a drain section cleaning liquid discharging pipe.

With a scrubber configured like this,
When the off-gas system is in operation, off-gas is sequentially fed into the container 2 from the gas inflow pipe 3, but the off-gas discharged downward at the opening at the lower end of the gas inflow pipe 3 is absorbed into the dust adsorption section 5. In principle, the flow spreads horizontally due to the lower flow path resistance. At this time, as explained with reference to FIG. 3, if the gas mass X deviates from the center of the gas inflow pipe 3, a phenomenon in which the upward flow of off-gas is biased toward one side of the dust adsorption section 5 tends to occur.

If such an imbalance in the upward flow of off-gas occurs, the gas mass will ascend while sequentially passing through the plurality of packed beds forming the dust adsorption section 5. In the lower packed bed A,
Even if it rises unbalanced, when this upward flow reaches the plenum part 8 from the packed bed A below, the flow path resistance is significantly reduced in the plenum part 8, resulting in a pressure release state and spreading horizontally. However, since the flow path resistance of the next packed layer B increases, the bubbles become congested at the entrance (lower end) and spread further horizontally. It will be sent to layer B.

Therefore, the upward flow of off-gas flows into the packed beds A and B.
The off-gas discharged from the gas inflow pipe 3 into the cleaning liquid 1 is gradually diffused and made uniform while passing through the plurality of packed layers A and B. In this process,
Dust will be adsorbed.

Therefore, even if a large amount of off-gas is discharged at once, by dispersing it and bringing it into contact with the filler 10, it is possible to achieve an even dust adsorption effect, and also to reduce the liquid level of the cleaning liquid 1. Prevents pulsation and prevents dust components from turning into mist due to ripples.

Then, as shown by the arrows in FIG. 1, the off-gas spreads and flows upward in the dust adsorption section 5, and by operating the cooling device 6, the cleaning liquid 1 flows downward in this region. Therefore, a circulation flow is generated throughout the interior of the container 2, and the heat generated due to the dissolution of NOx in the off-gas into the cleaning liquid is removed.

In one embodiment, the filling layer has a two-divided structure, but it goes without saying that it is also effective to divide the filling layer into three or more.

``Effect of the invention'' As explained above, the scrubber of the invention has a dust pipe that adsorbs dust by contacting with the upward flow of off-gas discharged into the cleaning liquid, around the gas inflow pipe that discharges off-gas downward. In addition to providing an adsorption part, the dust adsorption part is divided into a plurality of upper and lower parts, and a plenum part filled with cleaning liquid is provided between the divided parts, so that the amount of off-gas sent into the cleaning liquid can be reduced. Even when a gas mass is generated due to a sudden increase in the amount of gas, a pressure release state of upward flow occurs in the plenum due to a decrease in flow path resistance, and the flow path resistance increases in the next packed layer. By doing,
The upward flow is averaged, and the occurrence of ripples on the liquid surface can be suppressed.

The off-gas gradually becomes a uniform flow as it rises, so even if there is an uneven gas ejection,
The overall pulsating flow can be reduced.

The upward flow of off-gas in the dust adsorption section is made uniform, the dust adsorption effect is ensured, and the overall performance can be improved.

Therefore, the off-gas treatment in the post-treatment process of the scrubber can be simplified, and the adsorption efficiency in the dust adsorption section can be improved.

It has excellent effects such as

[Brief explanation of the drawing]

FIG. 1 is a front sectional view showing an embodiment of a scrubber according to the present invention, FIG. 2 is a perspective view of the dust suction part in FIG. 1, and FIG. 3 is a front sectional view showing a conventional example of the scrubber. DESCRIPTION OF SYMBOLS 1...Cleaning liquid, 2...Container, 3...Gas inflow pipe, 4...Casing for filler material, 5...Dust adsorption part, 6...Cooling device, 7...Gas outflow pipe, 8...
... Plenum part, 9 ... Metal mesh, 10 ... Filling material, 11 ... Cooling water inlet, 12 ... Cooling water outlet, 13 ... Cleaning liquid discharge device, 14 ... Drain part cleaning liquid discharge pipe, X ... Gas Mass, Y... Bubbles, G...
interval.

Claims (1)

[Scope of utility model registration request] Dust adsorption involves providing a gas inflow pipe for discharging off-gas downward in a container that stores cleaning liquid, and adsorbing dust by contacting the upward flow of off-gas discharged into the cleaning liquid around the gas inflow pipe. A scrubber characterized in that the dust adsorption part is divided into a plurality of upper and lower parts, and a plenum part filled with a cleaning liquid is provided between the divided parts.