JP3511855B2 - Defoaming equipment for cleaning equipment such as steel strip - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a facility for supplying a cleaning liquid to a steel strip or the like in a cleaning tank to clean the steel strip or the like. The present invention relates to a defoaming device capable of discharging a larger amount of water than before and efficiently defoaming the discharged foam. 2. Description of the Related Art Among cleaning equipment for steel strips and the like, a cleaning equipment using a cleaning liquid always supplies a cleaning liquid with a certain flow rate to a cleaning portion in order to increase the cleaning performance. I have.
Therefore, the supplied liquid involves air and the like, and bubbles are generated. Normally, the cleaning equipment has a tank structure having an entrance and an exit of a steel strip or the like. When the generation of the foam increases, the foam flows out from the entrance and the exit, and the outflow cannot be collected. In such a situation, Japanese Patent Laid-Open No.
No. 53887 discloses a method in which bubbles are discharged from a washing tank to another tank for bubbles, and fountains or the like are irradiated on the bubbles in the middle of the discharge pipe or in the defoaming tank to defoam and liquefy the bubbles. And a method of recovering. Conventionally, this method is often used (hereinafter, referred to as “prior art”). [0004] However, in the prior art, when the amount of foam exceeds the amount of foam discharged from the washing tank, the foam flows out from the inlet / outlet of a steel strip or the like of the washing tank. There is a problem that it will. Further, even if the foam was sufficiently discharged from the washing tank to the defoaming device, the discharged foam had insufficient defoaming ability, so the discharge amount exceeded the defoaming ability, and as a result, The discharge of the foam stops, and the foam flows out from the inlet / outlet of the steel strip or the like, and the outflow cannot be recovered. Therefore, in order to reduce this, a large amount of antifoaming agent must be used. [0005] Accordingly, an object of the present invention is to solve the above-mentioned problems, and to discharge a larger amount of foam foamed in a washing tank than before, and to eliminate almost 100% of the discharged foam. It is an object of the present invention to provide a defoaming apparatus for cleaning equipment such as a steel strip, which has a large defoaming ability and is capable of collecting and circulating a defoamed and liquefied cleaning liquid. Means for Solving the Problems The invention according to claim 1 is:
In an apparatus for defoaming foam generated in a cleaning tank provided in a cleaning facility such as a steel strip, an antifoam box having an antifoam plate,
An ejector for sucking foam generated in the cleaning tank, discharging the foam from the cleaning tank, injecting the discharged foam into the defoaming box to collide with the defoaming plate, Is characterized in that its suction port is connected to the washing tank and its discharge port is connected to the defoaming box. [0007] The ejector has its inlet connected directly to the washing tank and its outlet connected to a defoaming box. The ejector sucks the foam in the cleaning tank and discharges the foam out of the cleaning tank.The discharged foam is sprayed from the outlet of the ejector toward the defoaming plate inside the defoaming box to collide and defoam. Liquefy. Further, since the liquefied cleaning liquid accumulates in the defoaming box, the cleaning liquid can be efficiently used by returning it to the cleaning equipment by the cleaning liquid circulation system. [0008] As the ejector, a steam ejector, an air ejector and the like can be used. By using a steam ejector having a suction pressure of about 1/10 of 1000 mmH ₂ O, ie, an atmospheric pressure: 10 mH ₂ O, as an ejector, a much larger amount of foam can be removed from the cleaning tank compared to the prior art. It is possible to discharge. Furthermore, since the foam sucked by the ejector is jetted toward the defoaming plate of the defoaming box and collided, almost 100% of the foam sucked in a large amount can be defoamed and liquefied. Therefore, the amount of the defoamer used can be significantly reduced. Next, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a process chart showing an embodiment of the present invention. The cleaning equipment includes a cleaning tank 5, in which an electrode 3 wound around the strip 1, an electrode 2 provided close to the strip 1, and a spray nozzle 4 for cleaning liquid. Is provided. The defoaming device of the present invention includes a defoaming box 10 having a defoaming plate 11 and a steam ejector 9. 13
Is a suction port of the steam ejector 9 and the cleaning tank 5
It is connected to the. Reference numeral 12 denotes steam injected to the steam ejector 9. The outlet of the steam ejector 9 is connected to the defoaming box 10. The defoaming plate 11 is formed of a net-like baffle plate, and the foam discharged from the discharge port of the steam ejector 9 is jetted toward the defoaming plate 11 and collides. Then, the colliding foam is changed to a liquid and defoamed. The liquefied liquid (cleaning liquid) is stored in the defoaming box 10. In the present embodiment, a cleaning liquid circulation tank 6 is further provided, and the tank 6 is electrically connected to the defoaming box 10 via a return conduit 14 and to the cleaning tank 5 via a conduit 16. The cleaning liquid in the foam box 10 and the cleaning tank 5 is stored in the tank 6. Further, the cleaning liquid in the tank 6 is returned to the cleaning equipment by the circulating pump 7 via the conduit 17, so that the cleaning liquid can be circulated. [0010] In the cleaning equipment, the strip 1 is charged into the cleaning tank 5 from the inlet 8 and passes through the electrodes 2 and 3 filled with the alkaline cleaning liquid, and the gas generated by the electrolysis of water during the passage. Removes oil and the like on the surface and is washed. The spray liquid is supplied to the strip 1 by the spray nozzle 4 at a certain speed in order to keep the cleaning liquid of the electrodes 2 and 3 fresh at all times. The cleaning liquid is easily foamed because the oil component is settled by the alkali, and the cleaning liquid is sprayed onto the portion at a predetermined jetting speed as described above.
A large amount of foam 18 is generated inside. The foam generated in this way is sucked by the steam ejector 9 and the cleaning tank 5
And is sprayed toward the defoaming plate 11 in the defoaming box 10 to collide and defoam. Due to the use of the steam ejector 9, the suction port 13 has a pressure of about 1000 mmH ₂ O (about 1 atmosphere pressure).
Therefore, a large amount of foam is efficiently sent into the defoaming box 10. The defoamed and liquefied foam (cleaning liquid) is stored in the defoaming box 10 and stored in the cleaning liquid circulation tank 6 by the return conduit 14. Then, it is returned to the washing tank 5 by the circulation pump 7 and is circulated and collected. The liquefied foam (washing liquid) does not deteriorate its components, and the moisture mixed in the defoaming device balances with the moisture taken out by the curved exhaust blower 15 of the washing tank 5. The liquefied foam can be recovered without any modification, and can be circulated and used as a cleaning liquid. As described above, according to the present invention, a larger amount of foam can be discharged from the washing tank than before by using the ejector, and the foam can be discharged by using the defoaming box. Almost 100% of the defoamed foam can be defoamed, the foam does not flow out from the inlet and outlet of the steel strip, etc. of the cleaning tank, the reduction of the cleaning liquid is prevented, and the amount of defoamer used can be greatly reduced. Yes, thus providing an industrially useful effect.

[Brief description of the drawings] FIG. 1 is a process chart showing an embodiment of the present invention. [Explanation of symbols] 1 strip 2, 3 electrodes 4 spray nozzle 5 Cleaning tank 6 Cleaning liquid circulation tank 7 Circulation pump 8 entrance 9 Steam ejector 10 Antifoam box 11 Antifoam board 12 steam 13 Suction port 14 Return conduit 15 music blower 16 conduit 17 conduit 18 bubbles

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-7-60245 (JP, A) JP-A 8-71305 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) C23G 3/02

Claims (1)

(57) [Claim 1] An apparatus for defoaming foam generated in a cleaning tank provided in a cleaning facility for a steel strip or the like, comprising: a defoaming box having a defoaming plate; An ejector for inhaling the foam generated in the tank, discharging the foam from the cleaning tank, injecting the discharged foam into the defoaming box to collide with the defoaming plate, and the ejector includes: A defoaming device for cleaning equipment such as a steel strip, wherein a suction port is connected to the cleaning tank and a discharge port is connected to the defoaming box.