JPH081124A - Gas treatment device and gas treatment - Google Patents

Abstract

PURPOSE:To exhaust a harmful gas generated from the liquid surface of a tank in an effective manner by causing both gases which are discharged in a diagonally downward direction and a level direction respectively from two gas discharge ports, to collide with each other, and shutting off a gas in the tank from the outside, and at the same time, aspirating the gas from a gas suction port. CONSTITUTION:A pull duct 2 is arranged on one of the sides at the opening part of an acid pickling tank 1, and a push duct 3 is arranged at the edge on the opposite side. At the same time, another push duct 3' is arranged above the pull duct 2. In addition, an air curtain 12 is formed by causing a level jet and a diagonally downward jet discharged from both push ducts 3, 3' to collide with each other. A fresh air aspirated by an air blower 4 is supplied to both push ducts 3, 3' through a conduit 5. Further, a harmful gas and the jet in the acid pickling tank 1 is aspirated from the suction port 7 of the pull duct 2 through a conduit 8, using an exhaust fan 9. Thus the harmful gas and the jet are released into an atmosphere from a conduit 11 through a harmful gas treatment device 10.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to, for example, a steel material pickling tank,
Equipment and treatment to prevent harmful gas generated from plating tank, aluminum anodizing tank, electrolysis tank or heating furnace using a push-pull duct and prevent it from diffusing into the atmosphere above the tank. It is about the method.

[0002]

BACKGROUND OF THE INVENTION As a typical example of a method for preventing local exhaustion and diffusion of harmful gas such as acidic vapor generated from a liquid interface in a pickling tank or gas generated from an electrolysis tank to the upper side of the tank, As shown in FIG. 6, the jet duct 21 is discharged from the push duct 21 by a push-pull device in which a jet discharge push duct 21 is provided on one side of the upper part of the tank 20 and a pull duct 22 for sucking the jet is provided on the opposite side. An air curtain 23 is formed on the upper surface of the tank 20 by a jet flow to block harmful gas generated from the liquid interface in the tank 20 and becoming an upward flow, and the harmful gas is sucked by the pull duct 22 together with the jet flow.
There are ways to prevent exhaust and diffusion into the atmosphere.

In FIG. 6, 24 is an air blower, 25 is an exhaust fan, and 26 is a harmful gas treatment device. According to this method, the harmful gas generated from the liquid interface in the tank 20 is prevented from diffusing into the atmosphere above the tank 20, and the harmful gas treating apparatus 2 is provided.
6, but a large discharge flow rate from the push duct 21 for forming the air curtain 23 is required for the amount of harmful gas generated, and as a result, a large suction flow rate of the pull duct 22 is also necessary. Therefore, a large amount of energy is required, and a large volume of the harmful gas treatment device 26 is required.

By the way, the discharge jet forming the air curtain 23 is determined by the size and discharge velocity of the discharge port of the push duct 21, and the velocity distribution and the jet flow rate of the jet at the distance Z (m) from the discharge port are as follows. Formula (1),
It is represented by (2).

[0005]

[Equation 1]

That is, the jet flow rate is proportional to the 1/2 power of the distance Z and inversely proportional to the 1/2 power of the discharge port width a. Therefore, when the distance Z between the push duct and the pull duct increases, the atmospheric gases (I) and (II) above and below the jet flow are injected to increase the flow rate, and the flow velocity decreases due to the law of conservation of momentum. Means Further, as will be described later, as the jet flow is mixed in the jet flow as the distance increases, as the jet flow length increases, the harmful gas mixed in the jet flow is prevented from diffusing into the atmosphere. Must increase the ratio of the jet flow that must be sucked by the pull duct, and must increase the suction amount of the pull duct in proportion to the increase of the jet flow rate.

Further, the jet flow is about 10 to the jet center.
With a development angle of 13 °, the jet width XL is represented by the equation (4). XL = A + 2 · Z · tan (ψ) (4) Therefore, when the distance Z becomes large, the jet width XL becomes proportionally large, and when the jet is long, the suction port width of the pull duct 22 also becomes large in proportion to the distance Z. However, there is an inconvenience that the equipment is required, the equipment cost is increased, and the pickling operation of the pickling object into and out of the pickling tank is disturbed.

Further, as the distance Z increases, the jet velocity rapidly decreases, and the effect of shutting off the air curtain 23 by the jet decreases, so that it is easily affected by the air flow and disturbance of the atmosphere. For example, the harmful gas Qx rises up from the liquid interface inside the tank to shut off the air curtain 23 and the air curtain 2.
Although it is guided to the suction port of the pull duct 22 along the streamline of the amount of injection Q ₂ of the atmosphere (II) of 3 and locally discharged,
The jet of the air curtain 23 is formed by mixing and mixing harmful gas in the process, and if the formation is hindered by the outside airflow or the passage of the pickled product in and out, the total amount of the air curtain jet is It is not sucked into the pull duct 22 and partly flows out to the atmosphere (I) side, that is, the atmosphere side. Therefore, as the distance Z increases, the blocking effect of the air curtain 23 decreases, and the atmospheric diffusivity of harmful gas increases,
The risk of harmful gas diffusion increases.

In addition to the method described above, a method for preventing local exhaustion and diffusion of harmful gas such as acidic vapor generated from a liquid interface in a pickling tank or the like or gas generated from an electrolysis tank to the upper side of the tank. As shown in FIG. 7, as a typical example of
Providing a pair of pull ducts 28 on opposite sides of the upper part of the tank 27,
Further, by a push-pull device having a pair of push ducts 29 provided on the upper portion thereof, an air curtain 38 is formed on the upper surface of the tank 27 by jets of gases discharged from the discharge ports 32 of the push duct 29 so as to collide with each other, and the discharge is performed. The harmful gas generated from the liquid interface in the tank 27 due to the air flow split to the tank side due to the collision of the jet flows and becoming an upward flow is pulled by the pull duct 28.
There is also a method of guiding the harmful gas together with the jet flow through the pull duct 28 to exhaust the harmful gas, and preventing the harmful gas from diffusing into the atmosphere above the tank 27 by the blocking effect of the air curtain 38.

In FIG. 7, 30 is an air blower, 31 is a discharge air conduit, 34 is a suction gas conduit, 35 is an exhaust fan, and 3 is an air blower.
Reference numeral 6 is a harmful gas treatment device. According to this method, the cutoff distance Z of the air curtain can be half that in the method shown in FIG. 6, so the flow rate of the air forming the air curtain 38 is reduced, and therefore the suction flow rate in the tank 27 is small. The harmful gas generated from the liquid interface can be prevented from diffusing into the atmosphere above the tank 27 and discharged to the harmful gas treatment device 36.

However, in the method shown in FIG. 7, since a set of push-pull devices must be provided on the opposite side of the upper part of the tank 27, heights H ₁ and H ₂ are required, and a crane or the like for carrying the steel material to be processed is required. 6 is higher than that of the method shown in FIG. This may hinder the operation, and a work platform corresponding to the heights H ₁ and H ₂ of the push-pull device is used for observing the steel material processing situation in the tank and monitoring the steel material loading / unloading work. For example, a large amount of equipment cost is required for the operation and the manufacturing cost is increased.

[0012]

DISCLOSURE OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and is capable of efficiently exhausting harmful gas and preventing external diffusion, and is excellent in workability, particularly from outside the tank to inside the tank. It is an object of the present invention to provide a gas treatment technology that is excellent in workability toward a user, does not hinder driving operation, and can reduce various costs.

An object of the present invention is to provide a tank for generating gas, a gas suction port provided on an opening edge of the tank,
A first gas discharge port provided obliquely downward on the gas suction port and a second gas discharge port provided on the opening edge of the tank so as to face the gas suction port. The exit part,
Intake means connected to the gas suction port portion, air supply means connected to the first and second gas discharge port portions, and processing means for processing the gas sucked by the suction means. The gas discharged obliquely downward from the first gas discharge port and the gas discharged substantially horizontally from the second gas discharge port collide with each other, and The gas inside the tank is blocked from the outside by the flow,
It is achieved by a gas processing device characterized in that it is configured to be sucked from a gas suction port.

Further, a step of discharging gas from one side of the opening edge portion of the tank in a slanting downward direction, a step of discharging gas in a substantially horizontal direction from the opening edge portion on the opposite side, and A step of causing the gas discharged downward and the gas discharged substantially horizontally to collide with each other, and sucking together with the discharged gas at a position lower than the gas discharging position at the opening edge portion on one side of the tank. And a step of treating the sucked gas, the gas treatment method is achieved.

That is, according to the present invention, for example, a push-pull duct formed by vertically connecting a push duct and a pull duct is provided on one side of the tank opening edge, and only the push duct is provided on the opposite side of the tank opening edge. Is provided, and air is discharged from these opposing push ducts to form an air curtain, and the air curtains collide with each other on the tank to branch the flow into the tank side and the atmosphere side, It acts as if there is a partition plate orthogonal to the jet of the air curtain on the tank. And, by this action, the harmful gas generated from the liquid interface in the tank is blocked, the harmful gas in the tank is sucked together with the jet flow discharged from the push-pull duct from the suction port of the pull duct, and the detoxification process is performed. Since the push-pull ducts are opposed to each other, the cutoff distance of the air curtain may be small, and exhaust of harmful gas and prevention of external diffusion can be efficiently performed. In addition, the push-pull duct that interferes with the work may be provided only on one side of the opening, and the other side is low, so workability is excellent,
The operation becomes easy, and the facility cost and the manufacturing cost can be reduced.

In the above-described gas processing apparatus, the first and second gas discharge ports and the gas suction port collide with each other in the discharged gas near the center of the tank, and more than half of them are discharged to the tank side. It is preferable that they are provided in a positional relationship so as to divide the gas, so that the gas in the tank can be sucked / exhausted more uniformly. In addition, the gas generated near the gas suction port is guided to the gas suction port by a gas flow that collides and splits toward the tank side, and the gas generated near the second gas discharge port is It is preferable that the gas flow discharged from the second gas discharge port is guided to the gas suction port so that the discharge gas can be efficiently used without waste.

Further, the first and second gas discharge ports and the gas suction port may be provided in such a positional relationship that the air flow that collides toward the atmosphere side does not contain the gas in the tank. Preferably, this prevents the diffusion of harmful gases into the atmosphere. Hereinafter, the present invention will be described in detail based on examples.

[0018]

1 and 2 relate to a first embodiment of the present invention. FIG. 1 is a schematic view of a gas processing apparatus, and FIG. 2 is a flow rate distribution diagram of a jet flow and an ambient gas injection amount. . 1 in FIG.
Is a pickling tank, a pull duct 2 is provided on one side of the opening of the pickling tank 1, and a push duct 3 is provided on a side opposite to the pull duct 2, and above the pull duct 2. Is provided with a push duct 3 '.

The horizontal jet flow from the push duct 3 and the obliquely downward jet flow from the push duct 3'collide with each other. Reference numeral 4 is an air blower, and the fresh outside air sucked by the air blower 4 is supplied to the push ducts 3 and 3 ′ through the conduit 5. Reference numerals 6 and 6 ′ are discharge ports of the push ducts 3 and 3 ′, and 7 is a suction port of the pull duct 2. The discharge ports 6 and 6'have a width A and have the same length dimension L as the lengthwise dimension of the pickling tank 1, and the suction port 7 has a width B and the discharge ports 6 of the push ducts 3 and 3 '. , 6'have the same length dimension L.

Reference numeral 8 is a conduit continuing from the pull duct 2, 9 is an exhaust fan, 10 is a harmful gas treatment device, and 11 is a conduit opened to the atmosphere. That is, the harmful gas and jet in the pickling tank 1 are in the pull duct 2. The gas is sucked from the suction port 7 through the conduit 8 by the exhaust fan 9, sent to the harmful gas treatment device 10 and subjected to the detoxification treatment, and then discharged into the atmosphere by the conduit 11.

In the gas treatment apparatus of the present invention configured as described above, the jet air having the discharge flow rate U _O and the discharge flow rate Q ₀ jetted from the discharge port 6 of the push duct 3 and the discharge port 6'of the push duct 3 '. Thus, the air curtain 12 is formed. Incidentally, in this specification, Q _o ~Q _7, Q _x the even symbols for distinguishing gas, also used as a symbol representing the flow rate of the gas.

The air curtain 12 has an atmosphere above it.
(I), that is, air flow Q from the atmosphere₁With the
Lower atmosphere (II), ie pickling tank containing harmful gas
Air flow from internal gas Q₂The edge of the pickling tank 1
Jet Q from to the point of distance Z from ₃To form Therefore, Q₃= Q₀+ Q₁+ Q₂ (5) Q₁= Q₂ (6) holds.

The flow rate of the jet Q ₃ are calculated by equation (2), In addition, since the plated inclusive of air flow Q _1, Q ₂ are equal, equation (5), the air flow Q _1, Q ₂ (6) The flow rate can be calculated. The air curtain 12 formed by the jet air discharged from the pair of push ducts 3, 3 '
At approximately the center of the pickling tank 1, an upper flow Q ₄ toward the atmosphere (I) side, that is, the atmosphere side, and a lower flow Q ₅ toward the atmosphere (II) side, that is, toward the inside of the pickling tank 1 are divided.

Therefore, Q ₃ = Q ₄ + Q ₅ (7) holds, and Q ₅ + Q _x = Q ₂ + Q ₆ (8) holds due to the mass balance of the air flow in the pickling tank 1. In the jet flow of the air curtain 12, the mixed state of the air flow Q ₂ introduced from the atmosphere (II) is calculated by the following equations (9) and (10).

[0025]

[Equation 2]

However, regarding the variables a, c, x, ξ, Z and U _{O in} the above equations (9) and (10), the equations (1),
It is the same as that used in (2), and particularly for cc, cc = 0.1. Here, the injection flow rate Q ₃ at the distance Z (m) obtained from the equation (2), and the equation (9),
FIG. 2 shows the amount Q ₂ of gas entrained in the atmosphere (II) calculated by (10) in correspondence with the jet flow width XL calculated by the equation (3).

That is, the jet flow rate Q ₃ in the air curtain 12 has a flow rate distribution as shown by the curve α with respect to the jet flow width XL, and the atmosphere (II), that is, the gas in the pickling tank 1 containing the harmful gas. The amount of the air blown into the air flow Q ₂ has a flow rate distribution represented by a curve β with respect to the jet width XL. Therefore, when the suction flow rate Q ₆ and the harmful gas amount Q _x by the pull duct 2 are set, according to the equations (7) and (8),
The upper and lower flow rates Q ₄ and Q ₅ are calculated, and the branch point XE of the jet flow Q ₃ in FIG. 2 is determined by the equations (9) and (10).

When the suction flow rate Q ₆ is smaller than the specified value,
For example, when XE is point (a) in FIG. 2, this point (a) becomes a branch point of the jet Q ₃ , and the upper flow Q on the atmosphere side
₄ , the gas Q in the pickling tank corresponding to the shaded area in FIG.
_Will include ₇ . However, the gas amount Q ₇ in the pickling tank is calculated by the following equation (11).

[0029]

(Equation 3)

Therefore, the gas present in the pickling tank 1 is harmful.
Locally discharge all gas from the pull duct 2 and generate a jet Q₃upon
One way Q_FourDoes not include the gas in the pickling tank, that is, the pickling tank
Inner gas Q₇To prevent harmful gases from diffusing to the atmosphere.
In order to adjust the
The suction amount of the duct 2 may be set. by this,
Harmful gas Q generated from the liquid interface in the pickling tank 1_xOut of
Also generated from the push duct 3 near the pickling tank 1.
Is the air discharged from the discharge port 6 of the push duct 3.
-Air flow Q of curtain 12₂Mixed with air
Jet Q due to gas blocking effect and gas induction effect
₃In addition, near the center of the pickling tank 1
Jet Q of 12₃Is downward flow Q_FiveAnd suction flow Q ₆age
Is sucked from the suction port 7 of the pull duct 2.

Of the harmful gases Q _x generated from the liquid interface in the pickling tank 1, those generated near the pull duct 2 in the pickling tank 1 are located near the center of the pickling tank 1 in the air curtain 12. The suction flow Q ₆ is sucked from the suction port 7 of the pull duct 2 along the streamline of the downward flow Q ₅ of the jet flow Q ₃ . That is, the downward flow Q ₅ has an inductive local exhaust of harmful gases Q _x, noxious gas Q _x is subject to gas blocking and gas induction of downflow Q ₅ and the air curtain 12.

Incidentally, the specifications of the gas treatment apparatus of the present invention,
Table 1 shows the specifications of the conventional device configured to exert the same gas treatment capacity. Table 1 Conventional example of the present invention (Fig. 6) Conventional example (Fig. 7) Push duct discharge width A (m) 0.003 0.006 0.003 Push duct discharge length L (m) 4.0 2.0 4.0 Push duct dimension a (m) 0.08 0.110 0.077 Push duct Dimension b (m) 0.08 0.110 0.077 Pull duct dimension c (m) 0.167 0.190 0.077 Pull duct dimension d (m) 0.300 0.430 0.300 Pull duct suction port width B (m) 0.070 0.430 0.033 Air curtain shielding distance Z (m) 0.56 1.00 0.50 Discharge velocity U ₀ (m / sec) 10.6 10.0 10.0 Discharge flow rate Q ₀ (m ³ / sec) 0.127 0.120 0.120 Immersion flow rate Q ₁ (m ³ / sec) 0.396 0.350 0.350 Immersion flow rate Q ₂ (m ³ / sec) 0.396 0.350 0.350 Jet flow rate Q ₃ (m ³ / sec) 0.919 0.820 0.820 Flow rate at diversion point Q ₄ (m ³ / sec) 0.026 − 0.023 Flow rate at diversion point Q ₅ (m ³ / sec) 0.893 − 0.797 Harmful gas flow rate Q _x m ³ / sec) 0.003 0.003 0.003 Suction flow rate Q ₆ (m ³ / sec) 0.500 0.820 0.450 Jet flow velocity U _c (m / sec) 2.06 2.05 2 .05 Push-pull device height H ₁ (m) 0.08 0.110 0.410 Push-pull device height H ₂ (m) 0.45 0.430 0.410 That is, the suction flow rate of the present invention is smaller than that of the conventional device (FIG. 6). About 60% is sufficient, and since the suction amount is small, the running cost of the exhaust fan is low, and since the volume of the harmful gas treatment device can be reduced, the facility cost is also low and economical.

In the present invention, the height H ₁ of the push-pull device is 0.08 m, which is compared with the height H ₁ (0.41 m) of the push-pull device of the conventional device (FIG. 7). It is remarkably small and the workability is very good.
In the present invention, most of the air curtain jet becomes a downward flow, flows inside the pickling tank, and has a streamline directed to the suction port of the pull duct so as to guide harmful gas from the lower side of the pickling tank. Therefore, it is not likely to be adversely affected by factors such as obstructive wind from the atmosphere side and the factors that interfere with the formation of air curtains such as the work of pickling and pickling steel that is an object to be pickled into and from the pickling tank, and the risk of diffusing harmful gas into the atmosphere. Is small.

3 to 5 relate to the second, third and fourth embodiments of the present invention, respectively, and the basic technical concept thereof is substantially the same as that of the first embodiment described above. Therefore, the same constituents as those in the first embodiment are designated by the same reference numerals and the description thereof will be omitted. In the device of the second embodiment shown in FIG. 3, the pull duct 2 and the suction port 7 are connected in the lateral direction, and the height of the push-pull device can be made lower.

In the apparatus of the third embodiment shown in FIG. 4, the positions of the pull duct 2 and the suction port 7 are reversed.
It can be used when there is room to accommodate the pull duct 2 on the tank side. The apparatus of the fourth embodiment shown in FIG. 5 is used when there is no room to accommodate the pull duct 2 on the tank side.

[0036]

According to the present invention, the harmful gas generated from the liquid interface of the tank can be effectively exhausted, the suction flow rate at this time is small, the running cost of the exhaust fan is low, and the harmful gas treatment is performed. Since the equipment can have a small volume, the equipment cost can be reduced, and further, the work to be put in and out of the tank and other work can be easily performed without preparing a work stand or the like.

[Brief description of drawings]

FIG. 1 is a schematic view of a gas treatment device (first embodiment) of the present invention.

FIG. 2 is a flow rate distribution diagram of a jet flow and an entrained amount of atmospheric gas.

FIG. 3 is a schematic view of a main part of a gas treatment device (second embodiment).

FIG. 4 is a schematic view of a main part of a gas treatment device (third embodiment).

FIG. 5 is a schematic view of a main part of a gas treatment device (fourth embodiment).

FIG. 6 is a schematic view of a conventional gas treatment device.

FIG. 7 is a schematic view of a conventional gas treatment device.

[Explanation of symbols]

 1 Pickling tank 2 Pull duct 3,3 'Push duct 4 Air blower 5 Conduit 6,6' Discharge port 7 Suction port 8 Conduit 9 Exhaust fan 10 Hazardous gas treatment device 11 Conduit 12 Air curtain

Claims (5)

[Claims] 1. A tank for generating gas, a gas suction port provided on an opening edge of the tank, and a first gas provided in an obliquely downward direction above the gas suction port. A discharge port; a second gas discharge port provided on the opening edge of the tank so as to face the gas suction port; an intake means connected to the gas suction port; And a processing means for processing the gas sucked by the suction means, the gas supply means being connected to the second gas discharge port, and the obliquely downward direction from the first gas discharge port. So that the gas discharged into the chamber and the gas discharged from the second gas discharge port in a substantially horizontal direction collide with each other, and the gas inside these tanks is blocked from the outside by the gas flow, and the gas suction port A gas treatment device, wherein the gas treatment device is configured to be sucked from a part. 2. The first and second gas discharge ports and the gas suction port have a positional relationship such that the discharged gas collides near the center of the tank and more than half of the gas splits to the tank side. The gas treatment device according to claim 1, wherein the gas treatment device is provided. 3. A gas generated near the gas suction port is guided to the gas suction port by a gas flow that collides and splits and heads for the tank side, and a gas generated near the second gas discharge port. The gas processing apparatus according to claim 1 or 2, wherein the gas is discharged to the gas suction port by the gas flow discharged from the second gas discharge port. 4. The first and second gas discharge ports and the gas suction port are provided in such a positional relationship that an air flow that collides toward the atmosphere side does not contain the gas in the tank. The gas treatment device according to any one of claims 1 to 3, which is characterized. 5. A step of discharging gas from one side of the opening edge portion of the tank in a slanting downward direction, and a step of discharging gas in a substantially horizontal direction from the opening edge portion on the opposite side.
A step of colliding the gas discharged in the obliquely downward direction with the gas discharged in a substantially horizontal direction, and a position lower than the gas discharge position at the opening edge portion on one side of the tank together with the discharged gas And a step of treating the sucked gas.