JP2919201B2 - Method and apparatus for removing sludge from molten salt bath liquid - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for removing sludge from a molten salt bath for removing sludge mixed in the molten salt bath.

[0002]

2. Description of the Related Art For example, a salt bath nitrocarburizing apparatus is used as an apparatus for surface hardening a ferrous metal part such as a crankshaft which is an automobile part. This salt bath nitrocarburizing device is configured to perform a surface hardening treatment on the iron-based metal component by immersing the iron-based metal component in a salt bath solution obtained by heating and melting a salt bath agent to a predetermined temperature. I have.

In this case, sludge mixed into the molten salt bath solution increases with time due to the above-mentioned surface hardening operation, and the treatment quality of the iron-based metal part to be treated is deteriorated. . For this reason, various methods have conventionally been used to remove sludge in the molten salt bath liquid. For example, a pot formed of a metal net or the like is placed in a molten salt bath furnace in a molten salt bath furnace. There is known a method in which sludge is suspended by stirring a bath liquid, the stirring is stopped, and sludge settled at the bottom of the pot is taken out of a molten salt bath furnace integrally with the pot (hereinafter, referred to as a first method). One conventional example).

Further, as disclosed in Japanese Patent Application Laid-Open No. 56-127176, a molten salt bath solution in a molten salt bath is circulated to a separation vessel provided outside the molten salt bath by a pump or the like. A method is known in which sludge is separated by a fibrous thin wire lump collecting member disposed in the separation container, and the collecting member and the sludge are integrally disposed (hereinafter, referred to as a second method). Conventional example).

[0005]

However, in the first conventional example, since the operation of the molten salt bath furnace is stopped during the sludge removing operation, the operation efficiency of the salt bath nitrocarburizing apparatus is greatly reduced. I will. Moreover, the salt based salt contained in the separated sludge in a large amount is discarded together with the sludge. For this reason, a problem has been pointed out that the molten salt bath furnace must be frequently replenished with salt, which increases the running cost.

In the second conventional example, the sludge separated at the bottom of the separation vessel and the collecting member to which the sludge is attached settle down, and the salt of the salt bath base also accumulates at the bottom of the separation vessel. Would. Therefore, the salt is discarded together with the sludge and the collection member, which causes an increase in running cost. Furthermore, since the sludge is intricately intertwined with the collection member used once,
This collection member cannot be used repeatedly, which is uneconomical.

The present invention solves this kind of problem and can surely remove sludge in a molten salt bath solution, can effectively prevent the salt from being discarded, and can prevent repetition. It is an object of the present invention to provide a method and an apparatus for removing sludge in a molten salt bath liquid suitable for use.

[0008]

In order to achieve the above-mentioned object, the present invention provides a honeycomb-shaped ceramic filter member via a dispersion member in a sludge separation container provided outside a molten salt bath. the molten salt bath in the molten salt bath is dispersed by the dispersing member to circulate the sludge separation vessel after the sludge of the molten salt bath liquid was removed by the filter member, ultrasonic waves to the filter member The cleaning operation is performed.

[0009]

Further, it is preferable that the filter member is made of cordierite ceramics or mullite ceramics.

Further, the present invention provides a sludge separation container provided outside the molten salt bath and capable of circulating the molten salt bath with the molten salt bath, and a honeycomb shape disposed in the sludge separation container. a ceramic or mullite ceramic filter member cordierite, the tapering
The molten salt bath liquid is disposed in the separation vessel,
And a dispersion member for supplying to the filter member .

[0012]

According to the method and apparatus for removing sludge from a molten salt bath according to the present invention, when the molten salt bath in the molten salt bath is circulated to the sludge separation container, the ceramic material disposed in the sludge separation container is removed. Sludge in the molten salt bath liquid is separated via the filter member. At that time, since the filter member has a honeycomb shape, the surface area is large, sludge in the molten salt bath can be effectively adhered, and salt passing through the salt is improved, so that the salt to be discarded is improved. It is possible to reduce as much as possible.

In addition, the molten salt bath is effective by the dispersing member.
Are distributed to the filter member,
Effective sludge removal processing will be performed.
Further, since the filter member to which the sludge is attached in the sludge separation container is subjected to an ultrasonic cleaning operation and the sludge is separated from the filter member, the filter member is used for a new sludge removing operation. Can be.

Further, since the filter member is made of porous cordierite ceramics or mullite ceramics, sludge can be more effectively adhered, and the sludge removal operation can be performed efficiently and reliably. It becomes possible to do.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The method for removing sludge from a molten salt bath according to the present invention will be described in detail below with reference to examples in connection with an apparatus for performing the method.

In FIG. 1, reference numeral 10 denotes a sludge removing apparatus according to the present embodiment. The sludge removing device 10 is provided outside the molten salt bath 12 and is capable of circulating the molten salt bath 14 with the molten salt bath 12. The sludge separating container 16 is disposed inside the sludge separating container 16. And a filter member 18 made of cordierite ceramic or mullite ceramic having a honeycomb shape.

The molten salt bath 12 is a tank 2 made of Inconel.
0, the bath 20 is filled with the molten salt bath 14, and one end of the tube 22 is immersed in the molten salt bath 14. A pump (not shown) is connected to one end of the pipe 22, and the other end of the pipe 22 is connected to the upper end of the sludge separation container 16.

The sludge separation container 16 is mounted on a frame member 24 provided at the upper end of the tank body 20. A plurality of holes 26 are formed in the side surface, and the bottom portion 28 has the same shape as the side surface. A hole 26 is formed. In the upper part of the sludge separation vessel 16, the molten salt bath liquid 14 discharged from the pipe 22 is dispersed over a wide range in the sludge separation vessel 16, and the pressure of the discharged molten salt bath liquid 14 is reduced. In order to prevent the molten salt bath liquid 14 from concentrating on some of the filter members 18, a dispersion member 29 having holes 26 is fixed.

As shown in FIG. 2, the filter member 18
Diameter D is 10-100 mm, thickness H is 3-50
1 mm square to 5 mm square cell 30
Are provided in the range of 10 to 500 pieces. Note that the filter member 18 may be formed in a square shape with one side of 10 mm to 100 mm.

Next, the operation of the thus configured sludge removing apparatus 10 will be described in relation to the sludge removing method according to the present embodiment.

When the salt bath in the molten salt bath 12 is heated to a predetermined temperature, a molten salt solution 14 is obtained. Then, the iron-based metal component, which is the material to be processed, is immersed in the molten salt bath solution 14 for a predetermined time, so that the surface-hardening process of the iron-based metal component, that is, the nitriding process is performed.

If the above nitriding treatment is continued, the amount of sludge accumulated in the molten salt bath solution 14 increases, and an operation for removing the sludge is performed as necessary. That is, a plurality of filter members 18 are disposed in advance in a sludge separation container 16 constituting the sludge removing device 10, and a pump (not shown) is driven to drive the molten salt bath 12.
The molten salt bath liquid 14 therein is pumped through the tube 22. The molten salt bath liquid 14 in the pipe 22 is supplied from the upper side of the sludge separation container 16 into the sludge separation container 16 through the hole 26 of the dispersion member 29, and the sludge is removed by the plurality of filter members 18. After that, it passes through the hole 26 of the bottom 28 and is returned from the lower hole 26 into the molten salt bath 12.

In this case, in this embodiment, the filter member 1
8 has a honeycomb shape, so that the sludge collecting property is ensured, and the salt of the salt bath base easily passes through, and the salt does not remain in the filter member 18.

Here, if the size of each cell 30 constituting the honeycomb is too large, the molten salt bath liquid 14 has good permeability but returns to the molten salt bath tank 12 without collecting sludge, while If the dimensions of the cell 30 are too small, clogging may be caused by the collected sludge or the like, and salt may be left. Therefore, the dimensions of the filter member 18 are set so that the diameter D is 10 mm to 100 mm and the thickness H is 3 mm to
By setting it to 50 mm and providing 10 to 500 cells 30 of 1 mm square to 5 mm square, the sludge collecting property and the salt passing property can be effectively maintained, and the waste salt Is reduced as much as possible, and an increase in running cost can be effectively prevented.

In particular, since the filter member 18 is formed of porous cordierite ceramics or mullite ceramics, the effect of improving the adsorbability of sludge and obtaining the effect of reliably collecting the sludge can be obtained. .

Further, the molten salt bath liquid 1 is dispersed through the dispersion member 29.
4 are dispersed over a wide range, so that some filter members 1
The molten salt bath liquid 14 does not concentrate on the filter 8, and partial deterioration of the filter member 18 can be prevented.

After the sludge removing operation has been performed for a predetermined time, the drive of the sludge removing device 10 is stopped, and the sludge separating container 16 is taken out of the frame member 24 with the filter member 18 housed therein. Next, the sludge separation container 16 is disposed in an ultrasonic cleaning device (not shown) to perform a predetermined ultrasonic cleaning operation, and a filter member 18 is provided.
Is separated from the filter member 18. Then, the filter member 18 from which the sludge has been removed is attached to the frame member 24 together with the sludge separation container 16.
And used for new sludge removal work.

Therefore, in this embodiment, the filter member 18
Is suitable for use a plurality of times, so that the advantage that running cost is greatly reduced as compared with the case where a conventional disposable collection member is used is obtained.

[0029]

According to the method and the apparatus for removing sludge from a molten salt bath according to the present invention, the following effects and advantages can be obtained.

When the molten salt bath liquid in the molten salt bath is circulated to the sludge separation vessel, the sludge in the molten salt bath liquid is separated via a ceramic filter member provided in the sludge separation vessel. You. At this time, since the filter member is a porous material having a honeycomb shape, sludge in the molten salt bath can be effectively attached, and the salt has good permeability and can be discarded. It is possible to reduce as much as possible. As a result, the running cost can be easily reduced.

In addition, the molten salt bath is effective by the dispersing member.
Are distributed to the filter member,
Effective sludge removal processing will be performed.
Further, the filter member to which the sludge is attached in the sludge separation container is subjected to an ultrasonic cleaning operation, and thus is repeatedly used for a new sludge removing operation. Therefore, it is considerably more economical than one using a disposable collection member.

Further, since the filter member is made of porous cordierite ceramics or mullite ceramics, sludge can be effectively adhered, and the operation of removing the sludge can be performed efficiently and reliably. It becomes possible.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of an apparatus for removing sludge in a molten salt bath liquid according to an embodiment of the present invention.

FIG. 2 is an enlarged perspective view of a filter member constituting the sludge removing device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 ... Sludge removal apparatus 12 ... Molten salt bath 14 ... Molten salt bath liquid 16 ... Sludge separation container 18 ... Filter member 28 ... Bottom 30 ... Cell

 ──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-61-53176 (JP, A) JP-A-62-244415 (JP, A) JP-B-62-14004 (JP, B2) JP-B-51- 24749 (JP, B2)

Claims (3)

(57) [Claims] 1. A honeycomb-shaped ceramic filter member is disposed via a dispersion member in a sludge separation container provided outside a molten salt bath, and the molten salt bath liquid in the molten salt bath is disposed.
Dispersing by the dispersing member and circulating through the sludge separation container, removing sludge in the molten salt bath liquid by the filter member , and then performing an ultrasonic cleaning operation on the filter member. A method for removing sludge in liquid. 2. The sludge removing method according to claim 1, wherein said filter member is made of cordierite ceramics or mullite ceramics. 3. A sludge separation container provided outside the molten salt bath and capable of circulating the molten salt bath with the molten salt bath, and a honeycomb-shaped cordierite disposed in the sludge separation container. A filter member made of ceramics or mullite ceramics and the sludge separation container are provided to separate the molten salt bath liquid.
A dispersion member for dispersing and supplying the filter member to the filter member .