JP2000189834A - Method and apparatus for purifying cleaning liquid - Google Patents

Abstract

PROBLEM TO BE SOLVED: To separate and remove sludge with a simple apparatus without corrosion even when a cleaning liquid such as a pickling liquid is treated and to circulate the cleaning liquid to be used by installing a nonmagnetic container which is arranged in a separation tank and makes sludge adhere to the container and a sludge removing apparatus. SOLUTION: Inlet side piping 1a for supplying a pickling liquid before sludge separation treatment and outlet side piping 1b for discharging the pickling liquid after separation treatment are connected to a separation tank 2. A nonmagnetic container 3 is installed in the separation tank 2, a magnetism generator 4 is installed in the container 3, sludge is made to adhere to the surface of the container by magnetic force, and the corrosion of the generator 4 is prevented. A sludge removing apparatus 9 is installed in the tank 2, and sludge adherent to the surface of the container and the coating surface of the generator 4. An inlet side valve 5a, an outlet side valve 5b, and a sludge discharge valve 7 are installed to prevent the mixing of the separated sludge into a pickling liquid.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cleaning apparatus and a cleaning method for a cleaning liquid circulated in a cleaning process for containers and steel materials. In particular, the present invention is suitable for a pickling solution purifying apparatus and a method for purifying a pickling solution which is used when a pickling solution is refluxed by separating scales contained in the pickling solution by pickling treatment of a steel material.

[0002]

2. Description of the Related Art In the manufacturing process of steel products such as plates, rods, pipes, etc., as a method of removing scale generated on the steel surface by heat treatment such as hot working or annealing, there are alkali molten salt treatment and neutral method. There are a method of dissolving and removing the scale itself as in a salt electrolytic treatment, and a method of dissolving and peeling the metal immediately below the scale by pickling.

[0003] In general, the former method is often applied when the scale is thin, and is often used, for example, in a finish continuous annealing and pickling line for a stainless steel strip. On the other hand, the latter method has a scale like carbon steel sheet after hot rolling.
In many cases, the scale is used in the case where the thickness is relatively thick. In this case, the exfoliated scale accumulates in the pickling solution and accumulates like a sludge at the bottom of the pickling tank. This deposit is called sludge. The sludge solidifies on standing and reacts with the pickling solution to deteriorate the pickling solution. For this reason, it is necessary to periodically discharge the sludge to the outside of the pickling tank, but not only the risk of acid damage due to acid, but also the operation must be stopped, so that the efficiency of pickling is reduced.

As a method of continuously removing the sludge, for example, Japanese Patent Publication No. 2-10874 and Japanese Patent Publication No.
JP 126876 discloses a facility for discharging sludge together with a pickling liquid outside a pickling tank and separating the sludge and the pickling liquid in a settling tank.

Japanese Patent Application Laid-Open No. 7-213941 discloses a facility in which a rotating disk having a magnetic force and a magnet roll are immersed in a cleaning liquid, and sludge adsorbed on the disk and the magnet roll is scraped off by a scraper and separated. I have.

[0006]

[Problems to be Solved by the Invention]
The equipment disclosed in Japanese Patent Publication No. 7-126876 and Japanese Patent Publication No. 7-126876 can remove sludge from the pickling tank,
In each case, gravity sedimentation is used to separate sludge and pickling liquid. This sedimentation method has a slow sludge settling speed,
Since the powdery scale hardly precipitates, there is a problem that the scale is returned to the pickling tank without settling.

The method disclosed in Japanese Patent Application Laid-Open No. 7-213941 has a problem that when the cleaning solution is an acid solution or an alkaline solution, the disk or the magnet roll is corroded. As can not be used. Another problem is that the sludge is not sufficiently scraped off due to abrasion of the disk or scraper.

SUMMARY OF THE INVENTION An object of the present invention is to provide a purification apparatus and a purification method capable of quickly separating and removing sludge without corrosion even with a cleaning liquid such as an pickling liquid, and using the cleaning liquid at reflux, with simple equipment. Is to provide.

[0009]

The present invention solves the above-mentioned problems, and the gist thereof is as follows (1) to (6).

(1) A cleaning liquid purifying apparatus for separating sludge containing iron contained in a cleaning liquid by magnetic force, comprising an inlet pipe provided with an inlet valve for supplying the cleaning liquid before separation, and a cleaning liquid after separation. A separation tank connected to an outlet pipe having an outlet valve for discharging, a non-magnetic container disposed inside the separation tank for attaching sludge, and a magnetic force generator inserted into the container and having a magnetic force And a sludge removal device provided inside the separation tank for removing sludge attached to the surface of the container, and a sludge discharge valve connected to the separation tank for discharging the removed sludge. Cleaning liquid purifier.

(2) The cleaning liquid purifying apparatus according to the above (1), further comprising an elevating mechanism for inserting and removing the magnetic force generating device from the container.

(3) A cleaning liquid purifying apparatus for separating sludge containing iron contained in the cleaning liquid by magnetic force, comprising an inlet pipe provided with an inlet valve for supplying the cleaning liquid before separation, and a cleaning liquid after separation. A separation tank connected to an outlet pipe provided with an outlet valve for discharging, a magnetic force generating device having a magnetic force disposed inside the separation tank and having an outer surface covered with a non-magnetic covering portion; A cleaning liquid purifying apparatus comprising: a sludge removing device provided inside a tank for removing sludge adhering to the surface of the coating portion; and a sludge discharging valve connected to the separation tank for discharging the removed sludge. .

(4) After using the cleaning liquid purifying apparatus described in the above (1) or (2) to attach sludge to the surface of the container, supply and discharge of the cleaning liquid are stopped by the inlet valve and the outlet valve. Removing the sludge adhering to the surface of the container with a sludge removing device, and discharging the removed sludge from a sludge discharge valve.

(5) Using the cleaning liquid purifying apparatus described in the above item (3), after depositing sludge on the surface of the coating portion, supply and discharge of the cleaning liquid are stopped by the inlet valve and the outlet valve, and then A method for purifying a cleaning liquid, comprising removing sludge adhering to the surface of the coating portion with a sludge removing device, and discharging the removed sludge from a sludge discharge valve.

(6) Using the cleaning liquid purifying apparatus according to any one of the above (1) to (3), the pickling liquid in the pickling tank for steel is circulated to remove scale in the pickling liquid. A method for pickling steel, wherein the pickling liquid after separation and removal is used under reflux.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of the present invention is directed to a pickling method for removing scale from the surface of a steel material by immersing the steel material in a pickling solution, the method comprising purifying a pickling solution mixed with sludge containing scale. An example is described.

FIG. 1 is a schematic diagram schematically showing an example of the apparatus of the present invention. FIG. 2 is a schematic diagram schematically showing an example of another apparatus of the present invention. In addition, in FIG.
1b is an inlet pipe and an outlet pipe, 2 is a separation tank, 3 is a container, 4 is a magnetic generator, 5a and 5b are inlet and outlet valves respectively, 6 is an air vent valve, 7 is a sludge discharge valve, 8 is a sludge treatment device, 9 is a sludge removal device, 10 is a sludge removal valve, 11 is a lifting device, 1
2 is an upper lid, 13 is a drain valve, and 14 is a covering part.

As shown in FIGS. 1 and 2, according to the present invention, an inlet pipe 1a for supplying pickling liquid before sludge separation processing and an outlet pipe 1b for discharging pickling liquid after sludge separation processing. Is connected to the separation tank 2 so that the pickling solution can be continuously processed. That is, the inlet pipe 1 is placed in the pickling tank (not shown).
By connecting a to the outlet pipe 1b, the pickling liquid in the pickling tank can be supplied to the separation tank 2, and the pickling liquid separated in the separation tank can be returned to the pickling tank.

As shown in FIG. 1, according to the apparatus of the present invention, a non-magnetic container 3 is provided inside the separation tank 2 and a magnetic generator 4 is provided inside the container. Sludge can be adhered to the surface of the container 3 by the action of the magnetic force of the magnetic generator by preventing contact with the liquid, so that corrosion of the magnetic generator can be prevented, and sludge removal, which will be described later. Sludge removal by the device becomes easy. The material of the container is not particularly limited as long as it is non-magnetic, and a material having excellent corrosion resistance can be selected. For example, vinyl chloride, FRP (fiber reinforced plastic), glass, or the like can be used. Further, the thickness of the container is preferably about 0.5 to 3.0 mm from the viewpoints of wear of the container and attenuation of the magnetic force.

As shown in FIG. 2, according to another apparatus of the present invention, a magnetic generator 4 is provided inside the separation tank 2, and a coating portion 14 covering the outer surface of the magnetic generator 4 is used. And the pickling solution is prevented from contacting the sludge with the magnetic force of the magnetic generator 4, thereby allowing sludge to adhere to the surface of the cover 14 (hereinafter, also referred to as “covered surface”). Corrosion of the device 4 can be prevented, and sludge removal by a sludge removing device 9 described later becomes easy. The material of the covering portion is not particularly limited as long as it is non-magnetic, and is, for example, vinyl chloride or FRP.
(Fiber reinforced plastic), glass, rubber, and the like. In addition, the thickness of the covering portion is 0.5 to 3.0 m.
m.

As shown in FIGS. 1 and 2, the sludge removing device 9 is provided in the separation tank 2, so that the sludge removing device 9 adheres to the surface of the container and the coating surface of the magnetic generating device without removing the container 3 and the magnetic generating device 4. Sludge can be removed. As the sludge removing device, a nozzle that ejects a liquid such as water or a mixture of a liquid and a gas or a solid is suitable. In addition, you may remove mechanically with a brush, a board, etc.

As shown in FIGS. 1 and 2, the inlet valve 5a
And the discharge side valve 5b and the sludge discharge valve 7 for discharging sludge prevent the sludge separated from the pickling liquid by magnetic force and removed by the sludge removing device 9 from being mixed into the pickling liquid. be able to. That is, supply and discharge of the pickling solution are stopped by the inlet valve 5a and the outlet valve 5b, respectively.
Is opened and the sludge removed by the sludge removal device 9 is discharged to the sludge treatment device 8, whereby the outlet valve 5b
Sludge mixed into the pickling liquid discharged from the tank and returned to the pickling tank can be prevented.

FIG. 3 is a longitudinal sectional view schematically showing an example of the structure of the magnetic generator shown in FIG. 1 and FIG. Sign 1
5 is a permanent magnet, 16 is an iron core, 17 is a fixing nut, and the same elements as those in FIGS.

As shown in FIG. 3, the magnetic generator 4 has a structure in which iron cores 16 and permanent magnets 15 are alternately arranged.
2 and a fixing nut 17, and are arranged such that the N poles and the S poles of the permanent magnet 15 face each other with the iron core 16 interposed therebetween. The magnetic force generated by the magnetism generating device 4
2 or the surface of the covering portion 14 in FIG.
It may be about 2,000 Gauss or more. Although the upper limit is not particularly limited, it is usually preferable to set the upper limit to 15,000 gauss or less because the size of the magnetic generator increases. In FIG. 3, the permanent magnet 1
5 is used, but an electromagnet may be used.

As shown in FIG. 1, the provision of the elevating mechanism 11 for inserting and removing the magnetic generator 4 from the container 3 allows the magnetic generator 4 to be removed from the container 3 and the container 3 to be opened. The removal ability of the sludge removal device 9 can be reduced. The lifting mechanism may be an air cylinder, a hydraulic cylinder, or the like, but may be other means as long as it can be raised and lowered.

As shown in FIGS. 1 and 2, a drain valve 13 is preferably connected to the separation tank 2. Before the sludge is discharged from the sludge discharge valve 7, the pickling liquid in the separation tank can be discharged and collected from the liquid drain valve 13, so that the cost of the pickling liquid can be reduced.

In FIGS. 1 and 2, if the speed of the pickling solution passing through the magnetic generator 4 is too high, the sludge that has once adhered is separated and the efficiency of separating the sludge is reduced, so that the speed of the pickling solution is reduced to about 1 m / s or less. Is good. Preferably 0.5 m / s
It is as follows.

FIG. 4 is a sectional view schematically showing another example of the apparatus of the present invention. 1 are denoted by the same reference numerals.
FIG. 5 is a cross-sectional view schematically showing another example of another apparatus of the present invention. 2 are denoted by the same reference numerals. As shown in FIG. 4, a plurality of non-magnetic containers 3 each having a magnetic generator 4 are disposed in the separation tank 2, and the outer surface is covered with a non-magnetic covering portion 14, as shown in FIG. By disposing the plurality of magnetic generators 4 separated in the separation tank 2, the sludge separation ability is improved, and the cleaning liquid purification ability can be enhanced. 4 and 5 show an example in which a plurality of the separation tanks are arranged in the longitudinal direction (horizontal direction in the drawing), but a plurality of separation tanks are arranged in the width direction (vertical direction in the drawing) or in the width direction and the longitudinal direction. It may be provided.

Next, the purification method of the present invention will be described with reference to the purification of a pickling solution in a pickling tank as an example. In FIG. 1 and FIG. 2, the pickling liquid in the pickling tank (not shown) flows from the inlet pipe 1a through the separation tank 2 and returns to the pickling tank via the outlet pipe 1b. When the pickling solution passes through the separation tank, the sludge in the pickling solution adheres to the surface of the container 3 in FIG. 1 and to the surface of the coating portion 14 in FIG. Separation tank 2
After the pickling liquid is supplied for a predetermined period of time (this time is referred to as "liquid passing time"), the inlet valve 5a and the outlet valve 5b are closed to stop the supply and discharge of the pickling liquid. The flow time is
From the viewpoint of sludge adsorption efficiency, it is usually about 1 to 10 minutes.

Next, the air release valve 6 and the sludge discharge valve 7 are opened, and thereafter, for example, water is sprayed by using a sludge removing device 9, so that the surface of the container 3 in FIG.
In FIG. 2, sludge adhering to the surface of the coating portion 14 is removed and discharged to the sludge treatment device 8. Before discharging the sludge, it is desirable to open the liquid drain valve 13 and discharge and collect the pickling liquid in the separation tank. Also, in FIG. 1, when removing sludge, it is preferable to pull out the magnetic generator 4 from the container 3, so that sludge removal efficiency can be increased.

After the sludge is discharged, the sludge discharge valve 7 is closed, the inlet valve 1a and the outlet valve 1b are opened, and the liquid is started to flow into the separation tank 2, and the sludge is discharged to the surface of the container 3 or the coating portion 14. Adsorb sludge. By repeating such an operation, sludge of the pickling liquid is separated and removed, and the pickling liquid can be continuously treated and purified.

[0032]

EXAMPLES (Example 1) A test apparatus having a basic structure shown in FIG. 1 was manufactured, and a test for separating and purifying sludge in an acid pickling solution was performed. In FIG. 1, the test device has an outer diameter of 125 m.
m, an outer diameter of 7 mm inside a cylindrical separation tank 2 having a height of 230 mm.
A cylindrical container 3 having a height of 6.3 mm and a height of 220 mm is provided.
Outer diameter 70mm, height 210mm by air cylinder 11
The magnetic generator 4 of the above was configured to be insertable into and removable from the container, and a water jet nozzle 9 was provided inside the separation tank as a scale removing device. An inlet pipe 1a and an outlet pipe 1b having an inlet valve 5a and an outlet valve 5b, respectively, on the side of the separation tank.
And a sludge discharge valve 7 was attached to the lower part of the separation tank. As shown in FIG. 3, the magnetic generator 4 has an outer diameter of 7 mm.
With a structure in which nine 0 mm permanent magnets and an iron core were laminated, the magnetic force was 2000 to 6000 Gauss on the surface of the container.
The material of the container 3 is vinyl chloride, and the thickness thereof is 2.
5 mm.

The sludge is recovered from the pickling tank to produce a pickling solution having a sludge concentration of 0.24% and a particle diameter of 20 μm or less containing 70 to 80%, and this solution is supplied at a rate of 100 liter / min through an inlet pipe. The mixture was supplied to a separation tank, sludge was captured by a magnetic generator, and the pickling solution was discharged from an outlet pipe. After passing the solution for a predetermined time, the pickling solution inside the separation tank is discharged, and then
With the magnetic generator inserted into the container, water is injected by a water injection nozzle at a water pressure of 0.3 kg / cm ² to wash out sludge attached to the surface of the container, and the sludge is discharged from a sludge discharge valve. The amount was measured. In addition, sludge adhering to the surface of the container could be easily removed by water injection.

The sludge amount was 9 g in dry weight and 30 g in 30 minutes, and 15 g in 1 minute. Purification efficiency (sludge separation amount / sludge amount in pickling solution) per minute was 6.2.
It was 5% (15 g / 240 g × 100).

(Example 2) A test apparatus having the basic configuration shown in FIG. 2 was manufactured, and a test for separating and purifying sludge in the pickling solution was performed. The specifications of the test apparatus were the same as in Table 1 except that the container was not used and the magnetic generator was coated with vinyl chloride to a thickness of 1.5 mm. The solution was passed under the same conditions as described in Example 1, sludge attached to the coating surface of the magnetic generator was removed, and the weight was measured.

The amount of sludge was 23 g per 1 minute in a dry weight, and the purification efficiency was 9.5% (23 g / 240 g).
g × 100).

[0037]

According to the present invention, sludge can be separated and removed quickly with simple equipment without corrosive even with a pickling cleaning liquid, and the cleaning liquid can be used under reflux. The unit improves. It can be applied simply by connecting a pipe to an existing pickling tank, etc., and has great economic value such as reduction of sludge removal work and shortening of operation stoppage time due to removal work.

[Brief description of the drawings]

FIG. 1 is a schematic diagram schematically showing an example of the device of the present invention.

FIG. 2 is a schematic diagram schematically showing an example of another apparatus of the present invention.

FIG. 3 is a longitudinal sectional view schematically showing an example of the structure of a magnetic generator.

FIG. 4 is a cross-sectional view schematically showing another example of the device of the present invention.

FIG. 5 is a cross-sectional view schematically showing another example of another apparatus of the present invention.

[Explanation of symbols]

1a: inlet side pipe, 1b: outlet side pipe, 2: separation tank, 3: container, 4: magnetic generator, 5a: inlet side valve, 5b: outlet side valve, 6: air vent valve, 7: sludge discharge valve, 8: Sludge treatment device, 9: Sludge removal device (water injection valve), 10: Sludge removal valve, 11: Elevating device, 12: Top lid, 13: Drain valve, 14: Coating part, 15: Permanent magnet, 16: Iron core, 17: fixing nut.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Toru Matsuhashi 4-5-33 Kitahama, Chuo-ku, Osaka-shi Sumitomo Metal Industries Co., Ltd. F-term (reference) 3C047 GG13 GG17

Claims (6)

[Claims] An apparatus for purifying a cleaning liquid for separating sludge containing iron contained in the cleaning liquid by magnetic force, comprising an inlet pipe provided with an inlet valve for supplying the cleaning liquid before separation, and discharging the cleaning liquid after separation. A separation tank connected to an outlet pipe having an outlet valve, a non-magnetic container disposed inside the separation tank to attach sludge, and a magnetic force generator inserted into the container and having a magnetic force. A cleaning liquid provided with a sludge removing device provided inside the separation tank for removing sludge adhering to the surface of the container, and a sludge discharge valve connected to the separation tank for discharging the removed sludge. Purification device. 2. The cleaning liquid purifying apparatus according to claim 1, further comprising an elevating mechanism for inserting and removing the magnetic force generating device from the container. 3. A cleaning liquid purifying apparatus for separating sludge containing iron contained in a cleaning liquid by magnetic force, comprising an inlet pipe provided with an inlet valve for supplying the cleaning liquid before separation, and discharging the cleaning liquid after separation. Tank connected to an outlet pipe provided with an outlet valve, a magnetic force generator disposed inside the separation tank and having a magnetic force whose outer surface is covered with a nonmagnetic coating, and the separation tank A cleaning liquid purifying apparatus, comprising: a sludge removing device provided inside for removing sludge adhering to the surface of the coating portion; and a sludge discharging valve connected to the separation tank for discharging the removed sludge. 4. Using the cleaning liquid purifying apparatus according to claim 1 or 2, after applying sludge to the surface of the container, supply and discharge of the cleaning liquid are stopped by an inlet valve and an outlet valve, and then the sludge is removed. A method for purifying a cleaning liquid, comprising removing sludge adhering to the surface of the container with an apparatus and discharging the removed sludge from a sludge discharge valve. 5. Using the cleaning liquid purifying apparatus according to claim 3, after applying sludge to the surface of the covering section, supply and discharge of the cleaning liquid are stopped by an inlet valve and an outlet valve, and then the sludge removing apparatus is used. Removing the sludge adhering to the surface of the coating portion and discharging the removed sludge from a sludge discharge valve. 6. A cleaning liquid purifying apparatus according to claim 1, wherein the pickling liquid in the pickling tank for steel is circulated to remove and separate scales in the pickling liquid. A pickling method for steel materials, wherein the pickling solution is used under reflux.